@article{wichUsingDeepLearning2025,
	title = {Using {Deep} {Learning} to {Automate} {Orangutan} {Nest} {Detections} on {Aerial} {Images} {Collected} {With} {Drones}},
	volume = {87},
	issn = {0275-2565},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/ajp.70100},
	doi = {10.1002/ajp.70100},
	abstract = {ABSTRACT Traditional orangutan distribution and density monitoring requires costly line transect methods on the ground to detect their nests. Recently researchers have started to use unoccupied aerial vehicles, hereafter referred to as drones, to collect such data faster. However, manually inspecting the images acquired by the drone is time-consuming and hence costly. This study explored a deep learning method for the automated detection of orangutan nests in drone-captured aerial images, which can significantly improve the efficiency of orangutan monitoring efforts. The YOLO v10 model was trained using 868 images containing 1568 annotated orangutan nests collected from sites in Sabah, Malaysia, and Sumatra, Indonesia. Images were captured using multirotor and fixed-wing drones at varying altitudes. The model was trained using a transfer learning approach and achieved a mean Average Precision (mAP) of 0.831. The model was subsequently tested on two independent data sets with results showing a precision of 0.98 and recall of 0.88 for a multirotor drone and precision of 0.98 and a recall of 0.71 for a fixed-wing drone which has the benefit of being able to have longer duration flights. The high precision values indicate the model's accuracy in identifying true nest locations, while the recall values demonstrate its ability to detect a significant portion of the nests present in the images. The study highlights how using drones for data collection can reduce survey times compared to ground surveys, and the automation of nest detection further enhances the efficiency of drone surveys. However, the model's recall, especially for fixed-wing drone data, could be improved to ensure accurate population trend analyses. Further research should focus on expanding training data sets and refining models to account for different camera systems and environmental conditions.},
	number = {12},
	journal = {American Journal of Primatology},
	author = {Wich, Serge A and Ancrenaz, Marc and Goossens, Benoit and Hennekam, Molly and Milne, Sol and Burslem, David and Knott, Cheryl and Martin, Julien and Fergus, Paul},
	year = {2025},
	pages = {e70100},
}

ABSTRACT Traditional orangutan distribution and density monitoring requires costly line transect methods on the ground to detect their nests. Recently researchers have started to use unoccupied aerial vehicles, hereafter referred to as drones, to collect such data faster. However, manually inspecting the images acquired by the drone is time-consuming and hence costly. This study explored a deep learning method for the automated detection of orangutan nests in drone-captured aerial images, which can significantly improve the efficiency of orangutan monitoring efforts. The YOLO v10 model was trained using 868 images containing 1568 annotated orangutan nests collected from sites in Sabah, Malaysia, and Sumatra, Indonesia. Images were captured using multirotor and fixed-wing drones at varying altitudes. The model was trained using a transfer learning approach and achieved a mean Average Precision (mAP) of 0.831. The model was subsequently tested on two independent data sets with results showing a precision of 0.98 and recall of 0.88 for a multirotor drone and precision of 0.98 and a recall of 0.71 for a fixed-wing drone which has the benefit of being able to have longer duration flights. The high precision values indicate the model's accuracy in identifying true nest locations, while the recall values demonstrate its ability to detect a significant portion of the nests present in the images. The study highlights how using drones for data collection can reduce survey times compared to ground surveys, and the automation of nest detection further enhances the efficiency of drone surveys. However, the model's recall, especially for fixed-wing drone data, could be improved to ensure accurate population trend analyses. Further research should focus on expanding training data sets and refining models to account for different camera systems and environmental conditions.

@article{chalmersAIDrivenRealTimeMonitoring2025,
	title = {{AI}-{Driven} {Real}-{Time} {Monitoring} of {Ground}-{Nesting} {Birds}: {A} {Case} {Study} on {Curlew} {Detection} {Using} {YOLOv10}},
	volume = {17},
	issn = {2072-4292},
	url = {https://www.mdpi.com/2072-4292/17/5/769},
	number = {5},
	journal = {Remote Sensing},
	author = {Chalmers, Carl and Fergus, Paul and Wich, Serge and Longmore, Steven N. and Walsh, Naomi Davies and Oliver, Lee and Warrington, James and Quinlan, Julieanne and Appleby, Katie},
	year = {2025},
	pages = {769},
}

@article{lynamRisingTideConservation2025,
	title = {The rising tide of conservation technology: empowering the fight against poaching and unsustainable wildlife harvest},
	volume = {Volume 13 - 2025},
	issn = {2296-701X},
	shorttitle = {Application of conservation technology for reducing poaching and unsustainable wildlife harvest},
	url = {https://www.frontiersin.org/journals/ecology-and-evolution/articles/10.3389/fevo.2025.1527976},
	doi = {10.3389/fevo.2025.1527976},
	abstract = {IntroductionMarket-driven poaching and unsustainable wildlife harvest are significant drivers of population decline for numerous plant and animal species, including high-profile species like Asian and African elephants, wild cats, sharks and rays, and pangolins. This publication reviews the emerging role of conservation technology in combating this trade.Technologies and applicationsWe showcase how innovative technological tools are revolutionizing the detection and disruption of illegal and unsustainable wildlife trade, with a focus on those available to frontline staff working to prevent poaching and trafficking from source sites. We consider a diverse array of deployed technologies ranging from open-source software platforms, AI, and mobile apps to cutting-edge hardware, including camera traps, acoustic sensors, and remote sensing tools.Case studiesTo demonstrate the complex threats posed by IUWT to wildlife and the consequent need for tailored solutions, we present two case studies, one terrestrial and one marine, showcasing the importance of appropriate suites of technology tools for conservation implementation.DiscussionTechnology has potential to empower rangers, park staff, wildlife and fisheries inspectors, customs officials, police, and conservation practitioners with unprecedented capabilities to monitor threatened wildlife, detect illegal activities, gather evidence, and support law enforcement interventions.},
	language = {English},
	journal = {Frontiers in Ecology and Evolution},
	author = {Lynam, Antony John and Cronin, Drew T. and Wich, Serge A. and Steward, Jordan and Howe, Andrew and Kolla, Namrata and Markovina, Michael and Torrico, Omar and Reyes, Vanesa and Sophalrachana, Kong and Stevens, Xia and Schmidt, Eric and Cox, Henrik},
	month = may,
	year = {2025},
}

IntroductionMarket-driven poaching and unsustainable wildlife harvest are significant drivers of population decline for numerous plant and animal species, including high-profile species like Asian and African elephants, wild cats, sharks and rays, and pangolins. This publication reviews the emerging role of conservation technology in combating this trade.Technologies and applicationsWe showcase how innovative technological tools are revolutionizing the detection and disruption of illegal and unsustainable wildlife trade, with a focus on those available to frontline staff working to prevent poaching and trafficking from source sites. We consider a diverse array of deployed technologies ranging from open-source software platforms, AI, and mobile apps to cutting-edge hardware, including camera traps, acoustic sensors, and remote sensing tools.Case studiesTo demonstrate the complex threats posed by IUWT to wildlife and the consequent need for tailored solutions, we present two case studies, one terrestrial and one marine, showcasing the importance of appropriate suites of technology tools for conservation implementation.DiscussionTechnology has potential to empower rangers, park staff, wildlife and fisheries inspectors, customs officials, police, and conservation practitioners with unprecedented capabilities to monitor threatened wildlife, detect illegal activities, gather evidence, and support law enforcement interventions.

@article{ozigisCharacterizingCropDistribution2025,
	title = {Characterizing {Crop} {Distribution} and the {Impact} on {Forest} {Conservation} in {Central} {Africa}},
	volume = {17},
	issn = {2072-4292},
	url = {https://www.mdpi.com/2072-4292/17/11/1958},
	number = {11},
	journal = {Remote Sensing},
	author = {Ozigis, Mohammed S. and Wich, Serge and Abdolshahnejad, Mahsa and Descals, Adrià and Szantoi, Zoltan and Sheil, Douglas and Meijaard, Erik},
	year = {2025},
	pages = {1958},
}

@article{permanaObservationalSocialLearning2025,
	title = {Observational social learning of “know-how” and “know-what” in wild orangutans: evidence from nest-building skill acquisition},
	volume = {8},
	issn = {2399-3642},
	url = {https://doi.org/10.1038/s42003-025-08217-2},
	doi = {10.1038/s42003-025-08217-2},
	abstract = {Immature great apes learn how to build their nests over multiple years, yet how they do so has remained largely unclear. We investigated the detailed role of social learning in the acquisition of nest-building skills in wild Sumatran orangutans (Pongo abelii) using data on nest-building, nest practice, and nest peering behaviour from 44 individuals, collected over 17 years. We found that nest peering (but not being close to a nesting individual without peering) is associated with a significant increase in nest practice and is primarily directed at multi-step nest elements. Dependent immatures mostly peer at their mothers and use nest tree species in common with her, independent immatures peer at a larger range of individuals and use nest tree species in common with them. Our results suggest that orangutans acquire their nest-building skills through observational social learning, selective attention to “know-how” and the transmission of “know-what” information.},
	number = {1},
	journal = {Communications Biology},
	author = {Permana, Andrea L. and Permana, Junaidi Jaka and Nellissen, Lara and Prayogi, Eggi Septian and Prasetyo, Didik and Wich, Serge A. and van Schaik, Carel P. and Schuppli, Caroline},
	month = jun,
	year = {2025},
	pages = {890},
}

Immature great apes learn how to build their nests over multiple years, yet how they do so has remained largely unclear. We investigated the detailed role of social learning in the acquisition of nest-building skills in wild Sumatran orangutans (Pongo abelii) using data on nest-building, nest practice, and nest peering behaviour from 44 individuals, collected over 17 years. We found that nest peering (but not being close to a nesting individual without peering) is associated with a significant increase in nest practice and is primarily directed at multi-step nest elements. Dependent immatures mostly peer at their mothers and use nest tree species in common with her, independent immatures peer at a larger range of individuals and use nest tree species in common with them. Our results suggest that orangutans acquire their nest-building skills through observational social learning, selective attention to “know-how” and the transmission of “know-what” information.

@article{pinel-ramosAssessmentEffectivenessRGBCamera2025,
	title = {An {Assessment} of the {Effectiveness} of {RGB}-{Camera} {Drones} to {Monitor} {Arboreal} {Mammals} in {Tropical} {Forests}},
	volume = {9},
	issn = {2504-446X},
	url = {https://www.mdpi.com/2504-446X/9/9/622},
	number = {9},
	journal = {Drones},
	author = {Pinel-Ramos, Eduardo José and Aureli, Filippo and Wich, Serge and Rodrigues de Melo, Fabiano and Rezende, Camila and Brandão, Felipe and de Melo, Fabiana C. S. Alves and Spaan, Denise},
	year = {2025},
	pages = {622},
}

@article{pringleOpportunitiesChallengesMonitoring2025,
	title = {Opportunities and challenges for monitoring terrestrial biodiversity in the robotics age},
	issn = {2397-334X},
	url = {https://doi.org/10.1038/s41559-025-02704-9},
	doi = {10.1038/s41559-025-02704-9},
	abstract = {With biodiversity loss escalating globally, a step change is needed in our capacity to accurately monitor species populations across ecosystems. Robotic and autonomous systems (RAS) offer technological solutions that may substantially advance terrestrial biodiversity monitoring, but this potential is yet to be considered systematically. We used a modified Delphi technique to synthesize knowledge from 98 biodiversity experts and 31 RAS experts, who identified the major methodological barriers that currently hinder monitoring, and explored the opportunities and challenges that RAS offer in overcoming these barriers. Biodiversity experts identified four barrier categories: site access, species and individual identification, data handling and storage, and power and network availability. Robotics experts highlighted technologies that could overcome these barriers and identified the developments needed to facilitate RAS-based autonomous biodiversity monitoring. Some existing RAS could be optimized relatively easily to survey species but would require development to be suitable for monitoring of more ‘difficult’ taxa and robust enough to work under uncontrolled conditions within ecosystems. Other nascent technologies (for instance, new sensors and biodegradable robots) need accelerated research. Overall, it was felt that RAS could lead to major progress in monitoring of terrestrial biodiversity by supplementing rather than supplanting existing methods. Transdisciplinarity needs to be fostered between biodiversity and RAS experts so that future ideas and technologies can be codeveloped effectively.},
	journal = {Nature Ecology \& Evolution},
	author = {Pringle, Stephen and Dallimer, Martin and Goddard, Mark A. and Le Goff, Léni K. and Hart, Emma and Langdale, Simon J. and Fisher, Jessica C. and Abad, Sara-Adela and Ancrenaz, Marc and Angeoletto, Fabio and Auat Cheein, Fernando and Austen, Gail E. and Bailey, Joseph J. and Baldock, Katherine C. R. and Banin, Lindsay F. and Banks-Leite, Cristina and Barau, Aliyu S. and Bashyal, Reshu and Bates, Adam J. and Bicknell, Jake E. and Bielby, Jon and Bosilj, Petra and Bush, Emma R. and Butler, Simon J. and Carpenter, Dan and Clements, Christopher F. and Cully, Antoine and Davies, Kendi F. and Deere, Nicolas J. and Dodd, Michael and Drinkwater, Rosie and Driscoll, Don A. and Dutilleux, Guillaume and Dyrmann, Mads and Edwards, David P. and Farhadinia, Mohammad S. and Faruk, Aisyah and Field, Richard and Fletcher, Robert J. and Foster, Chris W. and Fox, Richard and Francksen, Richard M. and Franco, Aldina M. A. and Gainsbury, Alison M. and Gardner, Charlie J. and Giorgi, Ioanna and Griffiths, Richard A. and Hamaza, Salua and Hanheide, Marc and Hayward, Matt W. and Hedblom, Marcus and Helgason, Thorunn and Heon, Sui P. and Hughes, Kevin A. and Hunt, Edmund R. and Ingram, Daniel J. and Jackson-Mills, George and Jowett, Kelly and Keitt, Timothy H. and Kloepper, Laura N. and Kramer-Schadt, Stephanie and Labisko, Jim and Labrosse, Frédéric and Lawson, Jenna and Lecomte, Nicolas and de Lima, Ricardo F. and Littlewood, Nick A. and Marshall, Harry H. and Masala, Giovanni L. and Maskell, Lindsay C. and Matechou, Eleni and Mazzolai, Barbara and McConnell, Alistair and Melbourne, Brett A. and Miriyev, Aslan and Nana, Eric Djomo and Ossola, Alessandro and Papworth, Sarah and Parr, Catherine L. and Payo-Payo, Ana and Perry, Gad and Pettorelli, Nathalie and Pillay, Rajeev and Potts, Simon G. and Prendergast-Miller, Miranda T. and Qie, Lan and Rolley-Parnell, Persie and Rossiter, Stephen J. and Rowcliffe, Marcus and Rumble, Heather and Sadler, Jon P. and Sandom, Christopher J. and Sanyal, Asiem and Schrodt, Franziska and Sethi, Sarab S. and Shabrani, Adi and Siddall, Robert and Smith, Simón C. and Snep, Robbert P. H. and Soulsbury, Carl D. and Stanley, Margaret C. and Stephens, Philip A. and Stephenson, P. J. and Struebig, Matthew J. and Studley, Matthew and Svátek, Martin and Tang, Gilbert and Taylor, Nicholas K. and Umbers, Kate D. L. and Ward, Robert J. and White, Patrick J. C. and Whittingham, Mark J. and Wich, Serge and Williams, Christopher D. and Yakubu, Ibrahim B. and Yoh, Natalie and Zaidi, Syed A. R. and Zmarz, Anna and Zwerts, Joeri A. and Davies, Zoe G.},
	month = may,
	year = {2025},
}

With biodiversity loss escalating globally, a step change is needed in our capacity to accurately monitor species populations across ecosystems. Robotic and autonomous systems (RAS) offer technological solutions that may substantially advance terrestrial biodiversity monitoring, but this potential is yet to be considered systematically. We used a modified Delphi technique to synthesize knowledge from 98 biodiversity experts and 31 RAS experts, who identified the major methodological barriers that currently hinder monitoring, and explored the opportunities and challenges that RAS offer in overcoming these barriers. Biodiversity experts identified four barrier categories: site access, species and individual identification, data handling and storage, and power and network availability. Robotics experts highlighted technologies that could overcome these barriers and identified the developments needed to facilitate RAS-based autonomous biodiversity monitoring. Some existing RAS could be optimized relatively easily to survey species but would require development to be suitable for monitoring of more ‘difficult’ taxa and robust enough to work under uncontrolled conditions within ecosystems. Other nascent technologies (for instance, new sensors and biodegradable robots) need accelerated research. Overall, it was felt that RAS could lead to major progress in monitoring of terrestrial biodiversity by supplementing rather than supplanting existing methods. Transdisciplinarity needs to be fostered between biodiversity and RAS experts so that future ideas and technologies can be codeveloped effectively.

@article{sam-odusinaDetectionGeolocationPeat2025,
	title = {Detection and {Geolocation} of {Peat} {Fires} {Using} {Thermal} {Infrared} {Cameras} on {Drones}},
	volume = {9},
	issn = {2504-446X},
	url = {https://www.mdpi.com/2504-446X/9/7/459},
	number = {7},
	journal = {Drones},
	author = {Sam-Odusina, Temitope and Perkasa, Petrisly and Chalmers, Carl and Fergus, Paul and Longmore, Steven N. and Wich, Serge A.},
	year = {2025},
	pages = {459},
}

@article{thapaEyesSkyDrone2025,
	title = {Eyes in the sky: {Drone} monitoring of the largest gharial and mugger populations in the {East} {Rapti} {River}, {Chitwan} {National} {Park}},
	volume = {20},
	url = {https://doi.org/10.1371/journal.pone.0330350},
	doi = {10.1371/journal.pone.0330350},
	abstract = {Drone-based aerial monitoring can play a pivotal role in scaling up efforts to monitor species at risk. In this study, we assessed the population size, occupancy, and spatial interactions of gharials and muggers in the Eastern Rapti River and its tributaries within Chitwan National Park, complying with national regulations. Using a Wingtra Tail-Sitter Vertical Take-Off and Landing fixed-wing drone, we surveyed a 73-km river stretch during the species’ basking period. The drone captured 24,129 photographs across 27 flight missions, covering 702.66 km and 44.68 km², of which 153 contained dorsal images of gharials (77) and muggers (76). An experienced image analyst identified and counted 323 crocodiles (205 gharials and 118 muggers) from the images. The encounter rates were 14.33 gharials and 9.95 muggers detections per 1 hour of drone flight time. To measure habitat-use through an occupancy framework, we divided the 73-km river stretch into 809 grid cells of 0.04 km² each. The site-level probabilities of habitat-use were 0.47 for gharials and 0.24 for muggers. As anticipated, both species co-occurred spatially along the Eastern Rapti River during the winter season, with a spatial interaction factor (SIF) of 1.94. This study demonstrates the effectiveness of drones in collecting high-resolution ecological data—both spatial and temporal—for assessing population parameters and monitoring threatened crocodile species at scale. Drones offer a cost-effective and less labor-intensive ({\textasciitilde}US\$ 0.61 per km) alternative to traditional ground-based surveys ({\textasciitilde}US\$ 21 per km). Integrating machine learning with drone surveys for automated image analyses has significant potential to further reduce costs and increase efficiency and could strengthen conservation efforts across South Asian River system.},
	number = {8},
	journal = {PLOS ONE},
	author = {Thapa, Gokarna Jung and Thapa, Kanchan and Poudel, Shashank and Pun, Dil Bahadur Purja and Shrestha, Sujita and Poudel, Prem and Acharya, Hari Bhadra and Lamsal, Bal Kumar and Sada, Rajesh and Wich, Serge A.},
	year = {2025},
	pages = {e0330350},
}

Drone-based aerial monitoring can play a pivotal role in scaling up efforts to monitor species at risk. In this study, we assessed the population size, occupancy, and spatial interactions of gharials and muggers in the Eastern Rapti River and its tributaries within Chitwan National Park, complying with national regulations. Using a Wingtra Tail-Sitter Vertical Take-Off and Landing fixed-wing drone, we surveyed a 73-km river stretch during the species’ basking period. The drone captured 24,129 photographs across 27 flight missions, covering 702.66 km and 44.68 km², of which 153 contained dorsal images of gharials (77) and muggers (76). An experienced image analyst identified and counted 323 crocodiles (205 gharials and 118 muggers) from the images. The encounter rates were 14.33 gharials and 9.95 muggers detections per 1 hour of drone flight time. To measure habitat-use through an occupancy framework, we divided the 73-km river stretch into 809 grid cells of 0.04 km² each. The site-level probabilities of habitat-use were 0.47 for gharials and 0.24 for muggers. As anticipated, both species co-occurred spatially along the Eastern Rapti River during the winter season, with a spatial interaction factor (SIF) of 1.94. This study demonstrates the effectiveness of drones in collecting high-resolution ecological data—both spatial and temporal—for assessing population parameters and monitoring threatened crocodile species at scale. Drones offer a cost-effective and less labor-intensive (~US$ 0.61 per km) alternative to traditional ground-based surveys ({~}US$ 21 per km). Integrating machine learning with drone surveys for automated image analyses has significant potential to further reduce costs and increase efficiency and could strengthen conservation efforts across South Asian River system.

@article{descalsGlobalMappingOil2024a,
	title = {Global mapping of oil palm planting year from 1990 to 2021},
	volume = {16},
	issn = {1866-3516},
	url = {https://essd.copernicus.org/articles/16/5111/2024/},
	doi = {10.5194/essd-16-5111-2024},
	number = {11},
	journal = {Earth Syst. Sci. Data},
	author = {Descals, A. and Gaveau, D. L. A. and Wich, S. and Szantoi, Z. and Meijaard, E.},
	year = {2024},
	pages = {5111--5129},
}

@article{descalsGlobalMappingOil2024,
	title = {Global mapping of oil palm planting year from 1990 to 2021},
	volume = {16},
	issn = {1866-3516},
	url = {https://essd.copernicus.org/articles/16/5111/2024/},
	doi = {10.5194/essd-16-5111-2024},
	number = {11},
	journal = {Earth Syst. Sci. Data},
	author = {Descals, A. and Gaveau, D. L. A. and Wich, S. and Szantoi, Z. and Meijaard, E.},
	year = {2024},
	pages = {5111--5129},
}

@article{fergusHarnessingArtificialIntelligence2024,
	title = {Harnessing {Artificial} {Intelligence} for {Wildlife} {Conservation}},
	volume = {4},
	issn = {2673-7159},
	url = {https://www.mdpi.com/2673-7159/4/4/41},
	number = {4},
	journal = {Conservation},
	author = {Fergus, Paul and Chalmers, Carl and Longmore, Steven and Wich, Serge},
	year = {2024},
	pages = {685--702},
}

@article{gazagneDevelopmentGlobalThermal2024,
	title = {Development of a global thermal detection index to prioritize primate research with thermal drones},
	volume = {14},
	issn = {2045-2322},
	url = {https://doi.org/10.1038/s41598-024-77502-7},
	doi = {10.1038/s41598-024-77502-7},
	abstract = {Thermal Infrared (TIR) drones are emerging as effective tools for wildlife ecology monitoring and are increasingly employed in primate surveys. However, systematic methods for assessing primate detectability are lacking. We present a comprehensive approach utilizing a novel Thermal Detection Index (TDI) to evaluate the potential of TIR drones for primate monitoring. We developed TDIs for 389 primate species, considering activity patterns, locomotion types, body mass, densities, habitat utilization, and sleeping behaviors during diurnal and nocturnal surveys. Through the integration of TDIs with primates’ distribution and climatic variables (average annual temperature, precipitation, and wind speed), we established a Global TDI Suitability Score aimed at pinpointing species and regions most compatible with TIR drone-based monitoring. Atelidae, Cercopithecidae, and Indridae showed the highest TDI values, suggesting their suitability for TIR-drone surveys. We identified optimal regions in Africa, Asia and Latin America for primate monitoring with TIR drones, driven by favorable ecological conditions, habitat types, and high TDI species diversity. However, local ecological factors and regulatory frameworks also influence drone survey feasibility, necessitating careful consideration prior to implementation. Overall, our study provides a valuable framework for prioritizing primate species and regions for TIR drone-based monitoring, facilitating targeted conservation efforts and advancing primate monitoring research.},
	number = {1},
	journal = {Scientific Reports},
	author = {Gazagne, Eva and Gray, Russell J. and Wich, Serge and Hambuckers, Alain and Brotcorne, Fany},
	month = nov,
	year = {2024},
	pages = {27963},
}

Thermal Infrared (TIR) drones are emerging as effective tools for wildlife ecology monitoring and are increasingly employed in primate surveys. However, systematic methods for assessing primate detectability are lacking. We present a comprehensive approach utilizing a novel Thermal Detection Index (TDI) to evaluate the potential of TIR drones for primate monitoring. We developed TDIs for 389 primate species, considering activity patterns, locomotion types, body mass, densities, habitat utilization, and sleeping behaviors during diurnal and nocturnal surveys. Through the integration of TDIs with primates’ distribution and climatic variables (average annual temperature, precipitation, and wind speed), we established a Global TDI Suitability Score aimed at pinpointing species and regions most compatible with TIR drone-based monitoring. Atelidae, Cercopithecidae, and Indridae showed the highest TDI values, suggesting their suitability for TIR-drone surveys. We identified optimal regions in Africa, Asia and Latin America for primate monitoring with TIR drones, driven by favorable ecological conditions, habitat types, and high TDI species diversity. However, local ecological factors and regulatory frameworks also influence drone survey feasibility, necessitating careful consideration prior to implementation. Overall, our study provides a valuable framework for prioritizing primate species and regions for TIR drone-based monitoring, facilitating targeted conservation efforts and advancing primate monitoring research.

@article{pinel-ramosEvaluatingThermalInfrared2024,
	title = {Evaluating {Thermal} {Infrared} {Drone} {Flight} {Parameters} on {Spider} {Monkey} {Detection} in {Tropical} {Forests}},
	volume = {24},
	issn = {1424-8220},
	url = {https://www.mdpi.com/1424-8220/24/17/5659},
	number = {17},
	journal = {Sensors},
	author = {Pinel-Ramos, Eduardo José and Aureli, Filippo and Wich, Serge and Longmore, Steven and Spaan, Denise},
	year = {2024},
	pages = {5659},
}

@article{pinel-ramosBehavioralResponsesGeoffroys2024,
	title = {The {Behavioral} {Responses} of {Geoffroy}’s {Spider} {Monkeys} to {Drone} {Flights}},
	volume = {8},
	issn = {2504-446X},
	url = {https://www.mdpi.com/2504-446X/8/9/500},
	number = {9},
	journal = {Drones},
	author = {Pinel-Ramos, Eduardo José and Aureli, Filippo and Wich, Serge and Petersen, Merissa F. and Dias, Pedro A. D. and Spaan, Denise},
	year = {2024},
	pages = {500},
}

@article{trinh-dinhDronebasedPopulationSurvey2024,
	title = {A drone-based population survey of {Delacour}'s langur ({Trachypithecus} delacouri) in the karst forests of northern {Vietnam}},
	volume = {300},
	issn = {0006-3207},
	url = {https://www.sciencedirect.com/science/article/pii/S0006320724004038},
	doi = {10.1016/j.biocon.2024.110841},
	abstract = {The Critically Endangered Delacour's langur (Trachypithecus delacouri) is presently found only in a few isolated karst areas in northern Vietnam, where conducting field surveys has proven challenging due to the difficult terrain. Accurate population estimates from a scientifically sound method are needed to inform management of the species. From October to December 2022, we used a drone equipped with optical and thermal cameras to survey the species in Kim Bang Forest, a critical site for the species. We estimated langur abundance from the resulting point count data using N-mixture models including abiotic and biotic variables. We also compared the effectiveness and efficiency of the drone method with two commonly used ground-based methods. The drone survey recorded 16 groups with 104 individuals. We estimated a density of 0.87 groups per km2 and a population of 25 groups and 175 individuals. This estimate is 80–113 \% higher than previous ground-based estimates, attributed primarily to the higher area coverage by the drone survey. The estimate reaffirms the conservation importance of Kim Bang Forest for the species. The modelling also indicated that Delacour's langur abundance was correlated negatively with Assamese macaque (Macaca assamensis) presence and positively with vegetation productivity. Other variables (elevation, terrain ruggedness and distance to forest edge) were much less important in explaining langur abundance. Compared to the ground-based methods, the drone approach proved effective and resource-efficient for surveying Delacour's langurs. We recommend the drone method for future Delacour's langur surveys, with potential applicability to other arboreal mammals in difficult-to-access karst forests.},
	journal = {Biological Conservation},
	author = {Trinh-Dinh, Hoang and Wearn, Oliver R. and Ngoprasert, Dusit and Wich, Serge and Savini, Tommaso},
	month = dec,
	year = {2024},
	pages = {110841},
}

The Critically Endangered Delacour's langur (Trachypithecus delacouri) is presently found only in a few isolated karst areas in northern Vietnam, where conducting field surveys has proven challenging due to the difficult terrain. Accurate population estimates from a scientifically sound method are needed to inform management of the species. From October to December 2022, we used a drone equipped with optical and thermal cameras to survey the species in Kim Bang Forest, a critical site for the species. We estimated langur abundance from the resulting point count data using N-mixture models including abiotic and biotic variables. We also compared the effectiveness and efficiency of the drone method with two commonly used ground-based methods. The drone survey recorded 16 groups with 104 individuals. We estimated a density of 0.87 groups per km2 and a population of 25 groups and 175 individuals. This estimate is 80–113 % higher than previous ground-based estimates, attributed primarily to the higher area coverage by the drone survey. The estimate reaffirms the conservation importance of Kim Bang Forest for the species. The modelling also indicated that Delacour's langur abundance was correlated negatively with Assamese macaque (Macaca assamensis) presence and positively with vegetation productivity. Other variables (elevation, terrain ruggedness and distance to forest edge) were much less important in explaining langur abundance. Compared to the ground-based methods, the drone approach proved effective and resource-efficient for surveying Delacour's langurs. We recommend the drone method for future Delacour's langur surveys, with potential applicability to other arboreal mammals in difficult-to-access karst forests.

@article{fergusEmpoweringWildlifeGuardians2023,
	title = {Empowering wildlife guardians: an equitable digital stewardship and reward system for biodiversity conservation using deep learning and 3/{4G} camera traps},
	volume = {15},
	issn = {2072-4292},
	number = {11},
	journal = {Remote Sensing},
	author = {Fergus, Paul and Chalmers, Carl and Longmore, Steven and Wich, Serge and Warmenhove, Carmen and Swart, Jonathan and Ngongwane, Thuto and Burger, André and Ledgard, Jonathan and Meijaard, Erik},
	year = {2023},
	pages = {2730},
}

@article{wichUsingDronesDetermine2023,
	title = {Using {Drones} to {Determine} {Chimpanzee} {Absences} at the {Edge} of {Their} {Distribution} in {Western} {Tanzania}},
	volume = {15},
	issn = {2072-4292},
	number = {8},
	journal = {Remote Sensing},
	author = {Wich, Serge A and Bonnin, Noémie and Hutschenreiter, Anja and Piel, Alex K and Chitayat, Adrienne and Stewart, Fiona A and Pintea, Lilian and Kerby, Jeffrey T},
	year = {2023},
	pages = {2019},
}

@article{lameiraSocialityPredictsOrangutan2022,
	title = {Sociality predicts orangutan vocal phenotype},
	issn = {2397-334X},
	url = {https://doi.org/10.1038/s41559-022-01689-z},
	doi = {10.1038/s41559-022-01689-z},
	abstract = {In humans, individuals’ social setting determines which and how language is acquired. Social seclusion experiments show that sociality also guides vocal development in songbirds and marmoset monkeys, but absence of similar great ape data has been interpreted as support to saltational notions for language origin, even if such laboratorial protocols are unethical with great apes. Here we characterize the repertoire entropy of orangutan individuals and show that in the wild, different degrees of sociality across populations are associated with different ‘vocal personalities’ in the form of distinct regimes of alarm call variants. In high-density populations, individuals are vocally more original and acoustically unpredictable but new call variants are short lived, whereas individuals in low-density populations are more conformative and acoustically consistent but also exhibit more complex call repertoires. Findings provide non-invasive evidence that sociality predicts vocal phenotype in a wild great ape. They prove false hypotheses that discredit great apes as having hardwired vocal development programmes and non-plastic vocal behaviour. Social settings mould vocal output in hominids besides humans.},
	journal = {Nature Ecology \& Evolution},
	author = {Lameira, Adriano R. and Santamaría-Bonfil, Guillermo and Galeone, Deborah and Gamba, Marco and Hardus, Madeleine E. and Knott, Cheryl D. and Morrogh-Bernard, Helen and Nowak, Matthew G. and Campbell-Smith, Gail and Wich, Serge A.},
	month = mar,
	year = {2022},
}

In humans, individuals’ social setting determines which and how language is acquired. Social seclusion experiments show that sociality also guides vocal development in songbirds and marmoset monkeys, but absence of similar great ape data has been interpreted as support to saltational notions for language origin, even if such laboratorial protocols are unethical with great apes. Here we characterize the repertoire entropy of orangutan individuals and show that in the wild, different degrees of sociality across populations are associated with different ‘vocal personalities’ in the form of distinct regimes of alarm call variants. In high-density populations, individuals are vocally more original and acoustically unpredictable but new call variants are short lived, whereas individuals in low-density populations are more conformative and acoustically consistent but also exhibit more complex call repertoires. Findings provide non-invasive evidence that sociality predicts vocal phenotype in a wild great ape. They prove false hypotheses that discredit great apes as having hardwired vocal development programmes and non-plastic vocal behaviour. Social settings mould vocal output in hominids besides humans.

@article{meijaardRestoringOrangutanWhole2022,
	title = {Restoring the orangutan in a {Whole}- or {Half}-{Earth} context},
	issn = {0030-6053},
	url = {https://www.cambridge.org/core/article/restoring-the-orangutan-in-a-whole-or-halfearth-context/95C49E3F747CF09704C0E5E274D80B64},
	doi = {10.1017/S003060532200093X},
	abstract = {Various global-scale proposals exist to reduce the loss of biological diversity. These include the Half-Earth and Whole-Earth visions that respectively seek to set aside half the planet for wildlife conservation or to diversify conservation practices fundamentally and change the economic systems that determine environmental harm. Here we assess these visions in the specific context of Bornean orangutans Pongo pygmaeus and their conservation. Using an expert-led process we explored three scenarios over a 10-year time frame: continuation of Current Conditions, a Half-Earth approach and a Whole-Earth approach. In addition, we examined a 100-year population recovery scenario assuming 0\% offtake of Bornean orangutans. Current Conditions were predicted to result in a population c. 73\% of its current size by 2032. Half-Earth was judged comparatively easy to achieve and predicted to result in an orangutan population of c. 87\% of its current size by 2032. Whole-Earth was anticipated to lead to greater forest loss and ape killing, resulting in a prediction of c. 44\% of the current orangutan population for 2032. Finally, under the recovery scenario, populations could be c. 148\% of their current size by 2122. Although we acknowledge uncertainties in all of these predictions, we conclude that the Half-Earth and Whole-Earth visions operate along different timelines, with the implementation of Whole-Earth requiring too much time to benefit orangutans. None of the theorized proposals provided a complete solution, so drawing elements from each will be required. We provide recommendations for equitable outcomes.},
	journal = {Oryx},
	author = {Meijaard, Erik and Sheil, Douglas and Sherman, Julie and Chua, Liana and Ni'matullah, Safwanah and Wilson, Kerrie and Ancrenaz, Marc and Liswanto, Darmawan and Wich, Serge A. and Goossens, Benoit and Kühl, Hjalmar S. and Voigt, Maria and Rayadin, Yaya and Kurniawan, Yuyun and Trianto, Agus and Priatna, Dolly and Banes, Graham L. and Massingham, Emily and Payne, John and Marshall, Andrew J.},
	year = {2022},
	note = {Edition: 2022/10/13},
	pages = {1--12},
}

Various global-scale proposals exist to reduce the loss of biological diversity. These include the Half-Earth and Whole-Earth visions that respectively seek to set aside half the planet for wildlife conservation or to diversify conservation practices fundamentally and change the economic systems that determine environmental harm. Here we assess these visions in the specific context of Bornean orangutans Pongo pygmaeus and their conservation. Using an expert-led process we explored three scenarios over a 10-year time frame: continuation of Current Conditions, a Half-Earth approach and a Whole-Earth approach. In addition, we examined a 100-year population recovery scenario assuming 0% offtake of Bornean orangutans. Current Conditions were predicted to result in a population c. 73% of its current size by 2032. Half-Earth was judged comparatively easy to achieve and predicted to result in an orangutan population of c. 87% of its current size by 2032. Whole-Earth was anticipated to lead to greater forest loss and ape killing, resulting in a prediction of c. 44% of the current orangutan population for 2032. Finally, under the recovery scenario, populations could be c. 148% of their current size by 2122. Although we acknowledge uncertainties in all of these predictions, we conclude that the Half-Earth and Whole-Earth visions operate along different timelines, with the implementation of Whole-Earth requiring too much time to benefit orangutans. None of the theorized proposals provided a complete solution, so drawing elements from each will be required. We provide recommendations for equitable outcomes.

@article{mesquitaPracticalApproachDrones2022,
	title = {A practical approach with drones, smartphones, and tracking tags for potential real-time animal tracking},
	issn = {2396-9814},
	url = {https://doi.org/10.1093/cz/zoac029},
	doi = {10.1093/cz/zoac029},
	abstract = {Drones are increasingly used for fauna monitoring and wildlife tracking; however, their application for wildlife tracking is restricted by developing such systems. Here we explore the potential of drones for wildlife tracking using an off-the-shelf system that is easy to use by non-specialists consisting of a multirotor drone, smartphones, and commercial tracking devices via Bluetooth and Ultra-Wide Band (UWB). We present the system configuration, explore the operational parameters that can affect detection capabilities, and test the effectiveness of the system for locating targets by simulating target animals in savanna and forest environments. The self-contained tracking system was built without hardware or software customization. In 40 tracking flights carried out in the Brazilian Cerrado, we obtained a detection rate of 90\% in savanna and 40\% in forest areas. Tests for targets in movement (N = 20), the detection rates were 90\% in the savanna and 30\% in the forest areas. The spatial accuracy obtained by the system was 14.61 m, being significantly more accurate in savanna (x¯ = 10.53) than in forest areas (x¯ = 13.06). This approach to wildlife tracking facilitates the use of drones by non-specialists at an affordable cost for conservation projects with limited resources. The reduced size of the tags, the long battery life, and the lower cost compared to GPS-tags open up a range of opportunities for animal tracking.},
	urldate = {2022-05-21},
	journal = {Current Zoology},
	author = {Mesquita, Geison P and Mulero-Pázmány, Margarita and Wich, Serge A and Rodríguez-Teijeiro, José Domingo},
	year = {2022},
}

Drones are increasingly used for fauna monitoring and wildlife tracking; however, their application for wildlife tracking is restricted by developing such systems. Here we explore the potential of drones for wildlife tracking using an off-the-shelf system that is easy to use by non-specialists consisting of a multirotor drone, smartphones, and commercial tracking devices via Bluetooth and Ultra-Wide Band (UWB). We present the system configuration, explore the operational parameters that can affect detection capabilities, and test the effectiveness of the system for locating targets by simulating target animals in savanna and forest environments. The self-contained tracking system was built without hardware or software customization. In 40 tracking flights carried out in the Brazilian Cerrado, we obtained a detection rate of 90% in savanna and 40% in forest areas. Tests for targets in movement (N = 20), the detection rates were 90% in the savanna and 30% in the forest areas. The spatial accuracy obtained by the system was 14.61 m, being significantly more accurate in savanna (x¯ = 10.53) than in forest areas (x¯ = 13.06). This approach to wildlife tracking facilitates the use of drones by non-specialists at an affordable cost for conservation projects with limited resources. The reduced size of the tags, the long battery life, and the lower cost compared to GPS-tags open up a range of opportunities for animal tracking.

@article{mesquitaTerrestrialMegafaunaResponse2022,
	title = {Terrestrial {Megafauna} {Response} to {Drone} {Noise} {Levels} in {Ex} {Situ} {Areas}},
	volume = {6},
	issn = {2504-446X},
	url = {https://www.mdpi.com/2504-446X/6/11/333},
	number = {11},
	journal = {Drones},
	author = {Mesquita, Geison Pires and Mulero-Pázmány, Margarita and Wich, Serge A. and Rodríguez-Teijeiro, José Domingo},
	year = {2022},
	pages = {333},
}

@article{santikaEffectiveness20Years2022,
	title = {Effectiveness of 20 years of conservation investments in protecting orangutans},
	issn = {0960-9822},
	url = {https://www.sciencedirect.com/science/article/pii/S0960982222003153},
	doi = {10.1016/j.cub.2022.02.051},
	abstract = {Summary Conservation strategies are rarely systematically evaluated, which reduces transparency, hinders the cost-effective deployment of resources, and hides what works best in different contexts. Using data on the iconic and critically endangered orangutan (Pongo spp.), we developed a novel spatiotemporal framework for evaluating conservation investments. We show that around USD 1 billion was invested between 2000 and 2019 into orangutan conservation by governments, nongovernmental organizations, companies, and communities. Broken down by allocation to different conservation strategies, we find that habitat protection, patrolling, and public outreach had the greatest return on investment for maintaining orangutan populations. Given the variability in threats, land-use opportunity costs, and baseline remunerations in different regions, there were differential benefits per dollar invested across conservation activities and regions. We show that although challenging from a data and analysis perspective, it is possible to fully understand the relationships between conservation investments and outcomes and the external factors that influence these outcomes. Such analyses can provide improved guidance toward a more effective biodiversity conservation. Insights into the spatiotemporal interplays between the costs and benefits driving effectiveness can inform decisions about the most suitable orangutan conservation strategies for halting population declines. Although our study focuses on the three extant orangutan species of Sumatra and Borneo, our findings have broad application for evidence-based conservation science and practice worldwide.},
	journal = {Current Biology},
	author = {Santika, Truly and Sherman, Julie and Voigt, Maria and Ancrenaz, Marc and Wich, Serge A. and Wilson, Kerrie A. and Possingham, Hugh and Massingham, Emily and Seaman, Dave J. I. and Ashbury, Alison M. and Azvi, Taufiq S. and Banes, Graham L. and Barrow, Elizabeth J. and Burslem, David F. R. P. and Delgado, Robert A. and Erman, Andi and Fredriksson, Gabriella and Goossens, Benoit and Houghton, Max and Indrawan, Tito P. and Jaya, Ricko L. and Kanamori, Tomoko and Knott, Cheryl D. and Leiman, Ashley and Liswanto, Darmawan and Mach, Martin and Marshall, Andrew J. and Martin, Julien G. A. and Midora, Lelyana and Miller, Adam and Milne, Sol and Morgans, Courtney and Nardiyono, Nardi and Perwitasari-Farajallah, Dyah and Priatna, Dolly and Risch, Robert and Riyadi, Galuh M. and Russon, Anne and Sembiring, Juhardi and Setiawan, Endro and Sidiq, Mohammad and Simon, Donna and Spehar, Stephanie and Struebig, Matthew J. and Sumardi, Ibrahim and Tjiu, Albertus and Wahyudi, Rizki and Yanuar, Achmad and Meijaard, Erik},
	month = mar,
	year = {2022},
}

Summary Conservation strategies are rarely systematically evaluated, which reduces transparency, hinders the cost-effective deployment of resources, and hides what works best in different contexts. Using data on the iconic and critically endangered orangutan (Pongo spp.), we developed a novel spatiotemporal framework for evaluating conservation investments. We show that around USD 1 billion was invested between 2000 and 2019 into orangutan conservation by governments, nongovernmental organizations, companies, and communities. Broken down by allocation to different conservation strategies, we find that habitat protection, patrolling, and public outreach had the greatest return on investment for maintaining orangutan populations. Given the variability in threats, land-use opportunity costs, and baseline remunerations in different regions, there were differential benefits per dollar invested across conservation activities and regions. We show that although challenging from a data and analysis perspective, it is possible to fully understand the relationships between conservation investments and outcomes and the external factors that influence these outcomes. Such analyses can provide improved guidance toward a more effective biodiversity conservation. Insights into the spatiotemporal interplays between the costs and benefits driving effectiveness can inform decisions about the most suitable orangutan conservation strategies for halting population declines. Although our study focuses on the three extant orangutan species of Sumatra and Borneo, our findings have broad application for evidence-based conservation science and practice worldwide.

@article{westworthUnderstandingExternalInfluences2022,
	title = {Understanding {External} {Influences} on {Target} {Detection} and {Classification} {Using} {Camera} {Trap} {Images} and {Machine} {Learning}},
	volume = {22},
	issn = {1424-8220},
	url = {https://www.mdpi.com/1424-8220/22/14/5386},
	number = {14},
	journal = {Sensors},
	author = {Westworth, Sally O. A. and Chalmers, Carl and Fergus, Paul and Longmore, Steven N. and Piel, Alex K. and Wich, Serge A.},
	year = {2022},
	pages = {5386},
}

@article{amatoFermentedFoodConsumption2021,
	title = {Fermented food consumption in wild nonhuman primates and its ecological drivers},
	volume = {175},
	issn = {0002-9483},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/ajpa.24257},
	doi = {10.1002/ajpa.24257},
	abstract = {Abstract Objectives Although fermented food use is ubiquitous in humans, the ecological and evolutionary factors contributing to its emergence are unclear. Here we investigated the ecological contexts surrounding the consumption of fruits in the late stages of fermentation by wild primates to provide insight into its adaptive function. We hypothesized that climate, socioecological traits, and habitat patch size would influence the occurrence of this behavior due to effects on the environmental prevalence of late-stage fermented foods, the ability of primates to detect them, and potential nutritional benefits. Materials and methods We compiled data from field studies lasting at least 9 months to describe the contexts in which primates were observed consuming fruits in the late stages of fermentation. Using generalized linear mixed-effects models, we assessed the effects of 18 predictor variables on the occurrence of fermented food use in primates. Results Late-stage fermented foods were consumed by a wide taxonomic breadth of primates. However, they generally made up 0.01\%–3\% of the annual diet and were limited to a subset of fruit species, many of which are reported to have mechanical and chemical defenses against herbivores when not fermented. Additionally, late-stage fermented food consumption was best predicted by climate and habitat patch size. It was more likely to occur in larger habitat patches with lower annual mean rainfall and higher annual mean maximum temperatures. Discussion We posit that primates capitalize on the natural fermentation of some fruits as part of a nutritional strategy to maximize periods of fruit exploitation and/or access a wider range of plant species. We speculate that these factors contributed to the evolutionary emergence of the human propensity for fermented foods.},
	number = {3},
	journal = {American Journal of Physical Anthropology},
	author = {Amato, Katherine R. and Chaves, Óscar M. and Mallott, Elizabeth K. and Eppley, Timothy M. and Abreu, Filipa and Baden, Andrea L. and Barnett, Adrian A. and Bicca-Marques, Julio Cesar and Boyle, Sarah A. and Campbell, Christina J. and Chapman, Colin A. and De la Fuente, María Fernanda and Fan, Pengfei and Fashing, Peter J. and Felton, Annika and Fruth, Barbara and Fortes, Vanessa B. and Grueter, Cyril C. and Hohmann, Gottfried and Irwin, Mitchell and Matthews, Jaya K. and Mekonnen, Addisu and Melin, Amanda D. and Morgan, David B. and Ostner, Julia and Nguyen, Nga and Piel, Alex K. and Pinacho-Guendulain, Braulio and Quintino-Arêdes, Erika Patricia and Razanaparany, Patrick Tojotanjona and Schiel, Nicola and Sanz, Crickette M. and Schülke, Oliver and Shanee, Sam and Souto, Antonio and Souza-Alves, João Pedro and Stewart, Fiona and Stewart, Kathrine M. and Stone, Anita and Sun, Binghua and Tecot, Stacey and Valenta, Kim and Vogel, Erin R. and Wich, Serge and Zeng, Yan},
	year = {2021},
	pages = {513--530},
}

Abstract Objectives Although fermented food use is ubiquitous in humans, the ecological and evolutionary factors contributing to its emergence are unclear. Here we investigated the ecological contexts surrounding the consumption of fruits in the late stages of fermentation by wild primates to provide insight into its adaptive function. We hypothesized that climate, socioecological traits, and habitat patch size would influence the occurrence of this behavior due to effects on the environmental prevalence of late-stage fermented foods, the ability of primates to detect them, and potential nutritional benefits. Materials and methods We compiled data from field studies lasting at least 9 months to describe the contexts in which primates were observed consuming fruits in the late stages of fermentation. Using generalized linear mixed-effects models, we assessed the effects of 18 predictor variables on the occurrence of fermented food use in primates. Results Late-stage fermented foods were consumed by a wide taxonomic breadth of primates. However, they generally made up 0.01%–3% of the annual diet and were limited to a subset of fruit species, many of which are reported to have mechanical and chemical defenses against herbivores when not fermented. Additionally, late-stage fermented food consumption was best predicted by climate and habitat patch size. It was more likely to occur in larger habitat patches with lower annual mean rainfall and higher annual mean maximum temperatures. Discussion We posit that primates capitalize on the natural fermentation of some fruits as part of a nutritional strategy to maximize periods of fruit exploitation and/or access a wider range of plant species. We speculate that these factors contributed to the evolutionary emergence of the human propensity for fermented foods.

@article{chalmersVideoAnalysisDetection2021,
	title = {Video analysis for the detection of animals using convolutional neural networks and consumer-grade drones},
	volume = {9},
	issn = {2291-3467},
	number = {2},
	journal = {Journal of Unmanned Vehicle Systems},
	author = {Chalmers, Carl and Fergus, Paul and Curbelo Montanez, C Aday and Longmore, Steven N and Wich, Serge A},
	year = {2021},
	pages = {112--127},
}

@inproceedings{chalmersModellingAnimalBiodiversity2021,
	title = {Modelling {Animal} {Biodiversity} {Using} {Acoustic} {Monitoring} and {Deep} {Learning}},
	isbn = {2161-4407},
	doi = {10.1109/IJCNN52387.2021.9534195},
	author = {Chalmers, C. and Fergus, P. and Wich, S. and Longmore, S. N.},
	month = jul,
	year = {2021},
	pages = {1--7},
}

@article{chitayatEcologicalCorrelatesChimpanzee2021,
	title = {Ecological correlates of chimpanzee ({Pan} troglodytes schweinfurthii) density in {Mahale} {Mountains} {National} {Park}, {Tanzania}},
	volume = {16},
	url = {https://doi.org/10.1371/journal.pone.0246628},
	doi = {10.1371/journal.pone.0246628},
	abstract = {Understanding the ecological factors that drive animal density patterns in time and space is key to devising effective conservation strategies. In Tanzania, most chimpanzees ({\textasciitilde}75\%) live outside national parks where human activities threaten their habitat’s integrity and connectivity. Mahale Mountains National Park (MMNP), therefore, is a critical area for chimpanzees (Pan troglodytes schweinfurthii) in the region due to its location and protective status. Yet, despite its importance and long history of chimpanzee research ({\textgreater}50 years), a park-wide census of the species has never been conducted. The park is categorized as a savanna-woodland mosaic, interspersed with riparian forest, wooded grassland, and bamboo thicket. This heterogeneous landscape offers an excellent opportunity to assess the ecological characteristics associated with chimpanzee density, a topic still disputed, which could improve conservation plans that protect crucial chimpanzee habitat outside the park. We examined the influence of fine-scale vegetative characteristics and topographical features on chimpanzee nest density, modeling nest counts using hierarchical distance sampling. We counted 335 nests in forest and woodland habitats across 102 transects in 13 survey sites. Nests were disproportionately found more in or near evergreen forests, on steep slopes, and in feeding tree species. We calculated chimpanzee density in MMNP to be 0.23 ind/km2, although density varied substantially among sites (0.09–3.43 ind/km2). Density was associated with factors related to the availability of food and nesting trees, with topographic heterogeneity and the total basal area of feeding tree species identified as significant positive predictors. Species-rich habitats and floristic diversity likely play a principal role in shaping chimpanzee density within a predominately open landscape with low food abundance. Our results provide valuable baseline data for future monitoring efforts in MMNP and enhance our understanding of this endangered species’ density and distribution across Tanzania.},
	number = {2},
	journal = {PLOS ONE},
	author = {Chitayat, Adrienne B. and Wich, Serge A. and Lewis, Matthew and Stewart, Fiona A. and Piel, Alex K.},
	year = {2021},
	pages = {e0246628},
}

Understanding the ecological factors that drive animal density patterns in time and space is key to devising effective conservation strategies. In Tanzania, most chimpanzees (~75%) live outside national parks where human activities threaten their habitat’s integrity and connectivity. Mahale Mountains National Park (MMNP), therefore, is a critical area for chimpanzees (Pan troglodytes schweinfurthii) in the region due to its location and protective status. Yet, despite its importance and long history of chimpanzee research (\textgreater50 years), a park-wide census of the species has never been conducted. The park is categorized as a savanna-woodland mosaic, interspersed with riparian forest, wooded grassland, and bamboo thicket. This heterogeneous landscape offers an excellent opportunity to assess the ecological characteristics associated with chimpanzee density, a topic still disputed, which could improve conservation plans that protect crucial chimpanzee habitat outside the park. We examined the influence of fine-scale vegetative characteristics and topographical features on chimpanzee nest density, modeling nest counts using hierarchical distance sampling. We counted 335 nests in forest and woodland habitats across 102 transects in 13 survey sites. Nests were disproportionately found more in or near evergreen forests, on steep slopes, and in feeding tree species. We calculated chimpanzee density in MMNP to be 0.23 ind/km2, although density varied substantially among sites (0.09–3.43 ind/km2). Density was associated with factors related to the availability of food and nesting trees, with topographic heterogeneity and the total basal area of feeding tree species identified as significant positive predictors. Species-rich habitats and floristic diversity likely play a principal role in shaping chimpanzee density within a predominately open landscape with low food abundance. Our results provide valuable baseline data for future monitoring efforts in MMNP and enhance our understanding of this endangered species’ density and distribution across Tanzania.

@article{descalsHighresolutionGlobalMap2021,
	title = {High-resolution global map of smallholder and industrial closed-canopy oil palm plantations},
	volume = {13},
	issn = {1866-3516},
	url = {https://essd.copernicus.org/articles/13/1211/2021/},
	doi = {10.5194/essd-13-1211-2021},
	number = {3},
	journal = {Earth Syst. Sci. Data},
	author = {Descals, A. and Wich, S. and Meijaard, E. and Gaveau, D. L. A. and Peedell, S. and Szantoi, Z.},
	year = {2021},
	pages = {1211--1231},
}

@article{doullEvaluationFactorsAffecting2021,
	title = {An {Evaluation} of the {Factors} {Affecting} ‘{Poacher}’ {Detection} with {Drones} and the {Efficacy} of {Machine}-{Learning} for {Detection}},
	volume = {21},
	issn = {1424-8220},
	url = {https://www.mdpi.com/1424-8220/21/12/4074},
	number = {12},
	journal = {Sensors},
	author = {Doull, Katie E. and Chalmers, Carl and Fergus, Paul and Longmore, Steve and Piel, Alex K. and Wich, Serge A.},
	year = {2021},
	pages = {4074},
}

@article{lameiraOrangutanInformationBroadcast2021,
	title = {Orangutan information broadcast via consonant-like and vowel-like calls breaches mathematical models of linguistic evolution},
	volume = {17},
	url = {https://royalsocietypublishing.org/doi/abs/10.1098/rsbl.2021.0302 %X The origin of language is one of the most significant evolutionary milestones of life on Earth, but one of the most persevering scientific unknowns. Two decades ago, game theorists and mathematicians predicted that the first words and grammar emerged as a response to transmission errors and information loss in language's precursor system, however, empirical proof is lacking. Here, we assessed information loss in proto-consonants and proto-vowels in human pre-linguistic ancestors as proxied by orangutan consonant-like and vowel-like calls that compose syllable-like combinations. We played back and re-recorded calls at increasing distances across a structurally complex habitat (i.e. adverse to sound transmission). Consonant-like and vowel-like calls degraded acoustically over distance, but no information loss was detected regarding three distinct classes of information (viz. individual ID, context and population ID). Our results refute prevailing mathematical predictions and herald a turning point in language evolution theory and heuristics. Namely, explaining how the vocal–verbal continuum was crossed in the hominid family will benefit from future mathematical and computational models that, in order to enjoy empirical validity and superior explanatory power, will be informed by great ape behaviour and repertoire.},
	doi = {10.1098/rsbl.2021.0302},
	number = {9},
	journal = {Biology Letters},
	author = {Lameira, Adriano R. and Alexandre, António and Gamba, Marco and Nowak, Matthew G. and Vicente, Raquel and Wich, Serge},
	year = {2021},
	pages = {20210302},
}

@article{meijaardHistoricalRangeDrivers2021,
	title = {The historical range and drivers of decline of the {Tapanuli} orangutan},
	volume = {16},
	url = {https://doi.org/10.1371/journal.pone.0238087},
	doi = {10.1371/journal.pone.0238087},
	abstract = {The Tapanuli Orangutan (Pongo tapanuliensis) is the most threatened great ape species in the world. It is restricted to an area of about 1,000 km2 of upland forest where fewer than 800 animals survive in three declining subpopulations. Through a historical ecology approach involving analysis of newspaper, journals, books and museum records from the early 1800s to 2009, we demonstrate that historically Pongo tapanuliensis inhabited a much larger area, and occurred across a much wider range of habitat types and at lower elevations than now. Its current Extent of Occurrence is 2.5\% and 5.0\% of the historical range in the 1890s and 1940s respectively. A combination of historical fragmentation of forest habitats, mostly for small-scale agriculture, and unsustainable hunting likely drove various populations to the south, east and west of the current population to extinction. This happened prior to the industrial-scale forest conversion that started in the 1970s. Our findings indicate how sensitive P. tapanuliensis is to the combined effects of habitat fragmentation and unsustainable take-off rates. Saving this species will require prevention of any further fragmentation and killings or other removal of animals from the remaining population. Without concerted action to achieve this, the remaining populations of P. tapanuliensis are doomed to become extinct within several orangutan generations.},
	number = {1},
	journal = {PLOS ONE},
	author = {Meijaard, Erik and Ni’matullah, Safwanah and Dennis, Rona and Sherman, Julie and {Onrizal} and Wich, Serge A.},
	year = {2021},
	pages = {e0238087},
}

The Tapanuli Orangutan (Pongo tapanuliensis) is the most threatened great ape species in the world. It is restricted to an area of about 1,000 km2 of upland forest where fewer than 800 animals survive in three declining subpopulations. Through a historical ecology approach involving analysis of newspaper, journals, books and museum records from the early 1800s to 2009, we demonstrate that historically Pongo tapanuliensis inhabited a much larger area, and occurred across a much wider range of habitat types and at lower elevations than now. Its current Extent of Occurrence is 2.5% and 5.0% of the historical range in the 1890s and 1940s respectively. A combination of historical fragmentation of forest habitats, mostly for small-scale agriculture, and unsustainable hunting likely drove various populations to the south, east and west of the current population to extinction. This happened prior to the industrial-scale forest conversion that started in the 1970s. Our findings indicate how sensitive P. tapanuliensis is to the combined effects of habitat fragmentation and unsustainable take-off rates. Saving this species will require prevention of any further fragmentation and killings or other removal of animals from the remaining population. Without concerted action to achieve this, the remaining populations of P. tapanuliensis are doomed to become extinct within several orangutan generations.

@article{milneDriversBorneanOrangutan2021a,
	title = {Drivers of {Bornean} {Orangutan} {Distribution} across a {Multiple}-{Use} {Tropical} {Landscape}},
	volume = {13},
	issn = {2072-4292},
	url = {https://www.mdpi.com/2072-4292/13/3/458},
	number = {3},
	journal = {Remote Sensing},
	author = {Milne, Sol and Martin, Julien G. A. and Reynolds, Glen and Vairappan, Charles S. and Slade, Eleanor M. and Brodie, Jedediah F. and Wich, Serge A. and Williamson, Nicola and Burslem, David F. R. P.},
	year = {2021},
	pages = {458},
}

@article{milneDriversBorneanOrangutan2021,
	title = {Drivers of {Bornean} {Orangutan} {Distribution} across a {Multiple}-{Use} {Tropical} {Landscape}},
	volume = {13},
	issn = {2072-4292},
	url = {https://www.mdpi.com/2072-4292/13/3/458},
	number = {3},
	journal = {Remote Sensing},
	author = {Milne, Sol and Martin, Julien G. A. and Reynolds, Glen and Vairappan, Charles S. and Slade, Eleanor M. and Brodie, Jedediah F. and Wich, Serge A. and Williamson, Nicola and Burslem, David F. R. P.},
	year = {2021},
	pages = {458},
}

@incollection{morrisChallengesComputerVision2021,
	title = {Challenges for the computer vision community},
	isbn = {0-19-259084-7},
	booktitle = {Conservation {Technology}},
	publisher = {Oxford University Press},
	author = {Morris, Dan and Joppa, Lucas},
	editor = {Wich, S.A. and Piel, A. K.},
	year = {2021},
	pages = {225--238},
}

@article{plumptreWhereMightWe2021,
	title = {Where {Might} {We} {Find} {Ecologically} {Intact} {Communities}?},
	volume = {4},
	issn = {2624-893X},
	shorttitle = {Scoping ecological integrity},
	url = {https://www.frontiersin.org/article/10.3389/ffgc.2021.626635},
	doi = {10.3389/ffgc.2021.626635},
	abstract = {Conservation efforts should target the few remaining areas of the world that represent outstanding examples of ecological integrity and aim to restore ecological integrity to a much broader area of the world with intact habitat and minimal species loss while this is still possible. There have been many assessments of “intactness” in recent years but most of these use measures of anthropogenic impact at a site, rather than faunal intactness or ecological integrity. This paper makes the first assessment of faunal intactness for the global terrestrial land surface and assesses how many ecoregions have sites that could qualify as Key Biodiversity Areas (KBAs – sites contributing significantly to the global persistence of biodiversity) based on their outstanding ecological integrity (under KBA Criterion C). Three datasets are combined on species loss at sites to create a new spatially explicit map of numbers of species extirpated. Based on this map it is estimated that no more than 2.9\% of the land surface can be considered to be faunally intact. Additionally, using habitat/density distribution data for 15 large mammals we also make an initial assessment of areas where mammal densities are reduced, showing a further decrease in surface area to 2.8\% of the land surface that could be considered functionally intact. Only 11\% of the functionally intact areas that were identified are included within existing protected areas, and only 4\% within existing KBAs triggered by other criteria. Our findings show that the number of ecoregions that could qualify as Criterion C KBAs could potentially increase land area up to 20\% if their faunal composition was restored with the reintroduction of 1–5 species. Hence, if all necessary requirements are met in order to reintroduce species and regain faunal integrity, this will increase ecological integrity across much of the area where human impacts are low (human footprint ≤4). Focusing restoration efforts in these areas could significantly increase the area of the planet with full ecological integrity.},
	language = {English},
	number = {26},
	journal = {Frontiers in Forests and Global Change},
	author = {Plumptre, Andrew J. and Baisero, Daniele and Belote, R. Travis and Vázquez-Domínguez, Ella and Faurby, Soren and Jȩdrzejewski, Włodzimierz and Kiara, Henry and Kühl, Hjalmar and Benítez-López, Ana and Luna-Aranguré, Carlos and Voigt, Maria and Wich, Serge and Wint, William and Gallego-Zamorano, Juan and Boyd, Charlotte},
	month = apr,
	year = {2021},
}

Conservation efforts should target the few remaining areas of the world that represent outstanding examples of ecological integrity and aim to restore ecological integrity to a much broader area of the world with intact habitat and minimal species loss while this is still possible. There have been many assessments of “intactness” in recent years but most of these use measures of anthropogenic impact at a site, rather than faunal intactness or ecological integrity. This paper makes the first assessment of faunal intactness for the global terrestrial land surface and assesses how many ecoregions have sites that could qualify as Key Biodiversity Areas (KBAs – sites contributing significantly to the global persistence of biodiversity) based on their outstanding ecological integrity (under KBA Criterion C). Three datasets are combined on species loss at sites to create a new spatially explicit map of numbers of species extirpated. Based on this map it is estimated that no more than 2.9% of the land surface can be considered to be faunally intact. Additionally, using habitat/density distribution data for 15 large mammals we also make an initial assessment of areas where mammal densities are reduced, showing a further decrease in surface area to 2.8% of the land surface that could be considered functionally intact. Only 11% of the functionally intact areas that were identified are included within existing protected areas, and only 4% within existing KBAs triggered by other criteria. Our findings show that the number of ecoregions that could qualify as Criterion C KBAs could potentially increase land area up to 20% if their faunal composition was restored with the reintroduction of 1–5 species. Hence, if all necessary requirements are met in order to reintroduce species and regain faunal integrity, this will increase ecological integrity across much of the area where human impacts are low (human footprint ≤4). Focusing restoration efforts in these areas could significantly increase the area of the planet with full ecological integrity.

@article{seamanOrangutanMovementPopulation2021,
	title = {Orangutan movement and population dynamics across human-modified landscapes: implications of policy and management},
	issn = {1572-9761},
	url = {https://doi.org/10.1007/s10980-021-01286-8},
	doi = {10.1007/s10980-021-01286-8},
	abstract = {Agricultural expansion is a leading cause of deforestation and habitat fragmentation globally. Policies that support biodiversity and facilitate species movement across farmland are therefore central to sustainability efforts and wildlife conservation in these human-modified landscapes.},
	journal = {Landscape Ecology},
	author = {Seaman, Dave J. I. and Voigt, Maria and Bocedi, Greta and Travis, Justin M. J. and Palmer, Stephen C. F. and Ancrenaz, Marc and Wich, Serge and Meijaard, Erik and Bernard, Henry and Deere, Nicolas J. and Humle, Tatyana and Struebig, Matthew J.},
	month = jun,
	year = {2021},
}

Agricultural expansion is a leading cause of deforestation and habitat fragmentation globally. Policies that support biodiversity and facilitate species movement across farmland are therefore central to sustainability efforts and wildlife conservation in these human-modified landscapes.

@article{shermanDiseaseRiskConservation2021,
	title = {Disease {Risk} and {Conservation} {Implications} of {Orangutan} {Translocations}},
	volume = {8},
	issn = {2297-1769},
	shorttitle = {Orangutan translocation risks},
	url = {https://www.frontiersin.org/article/10.3389/fvets.2021.749547},
	doi = {10.3389/fvets.2021.749547},
	abstract = {Critically Endangered orangutans are translocated in several situations: reintroduced into historic range where no wild populations exist, released to reinforce existing wild populations, and wild-to-wild translocated to remove individuals from potentially risky situations. Translocated orangutans exposed to human diseases, including Coronavirus Disease 2019 (COVID-19), pose risks to wild and previously released conspecifics. Wildlife disease risk experts recommended halting great ape translocations during the COVID-19 pandemic to minimize risk of disease transmission to wild populations. We collected data on orangutan releases and associated disease risk management in Indonesia during the COVID-19 pandemic, and developed a problem description for orangutan disease and conservation risks. We identified that at least 15 rehabilitated ex-captive and 27 wild captured orangutans were released during the study period. Identified disease risks included several wild-to-wild translocated orangutans in direct contact or proximity to humans without protective equipment, and formerly captive rehabilitated orangutans that have had long periods of contact and potential exposure to human diseases. While translocation practitioners typically employ mitigation measures to decrease disease transmission likelihood, these measures cannot eliminate all risk, and are not consistently applied. COVID-19 and other diseases of human origin can be transmitted to orangutans, which could have catastrophic impacts on wild orangutans, other susceptible fauna, and humans should disease transmission occur. We recommend stakeholders conduct a Disease Risk Analysis for orangutan translocation, and improve pathogen surveillance and mitigation measures to decrease the likelihood of potential outbreaks. We also suggest refocusing conservation efforts on alternatives to wild-to-wild translocation including mitigating human-orangutan interactions, enforcing laws and protecting orangutan habitats to conserve orangutans in situ.},
	language = {English},
	number = {1290},
	journal = {Frontiers in Veterinary Science},
	author = {Sherman, Julie and Unwin, Steve and Travis, Dominic A. and Oram, Felicity and Wich, Serge A. and Jaya, Ricko L. and Voigt, Maria and Santika, Truly and Massingham, Emily and Seaman, Dave J. I. and Meijaard, Erik and Ancrenaz, Marc},
	month = nov,
	year = {2021},
}

Critically Endangered orangutans are translocated in several situations: reintroduced into historic range where no wild populations exist, released to reinforce existing wild populations, and wild-to-wild translocated to remove individuals from potentially risky situations. Translocated orangutans exposed to human diseases, including Coronavirus Disease 2019 (COVID-19), pose risks to wild and previously released conspecifics. Wildlife disease risk experts recommended halting great ape translocations during the COVID-19 pandemic to minimize risk of disease transmission to wild populations. We collected data on orangutan releases and associated disease risk management in Indonesia during the COVID-19 pandemic, and developed a problem description for orangutan disease and conservation risks. We identified that at least 15 rehabilitated ex-captive and 27 wild captured orangutans were released during the study period. Identified disease risks included several wild-to-wild translocated orangutans in direct contact or proximity to humans without protective equipment, and formerly captive rehabilitated orangutans that have had long periods of contact and potential exposure to human diseases. While translocation practitioners typically employ mitigation measures to decrease disease transmission likelihood, these measures cannot eliminate all risk, and are not consistently applied. COVID-19 and other diseases of human origin can be transmitted to orangutans, which could have catastrophic impacts on wild orangutans, other susceptible fauna, and humans should disease transmission occur. We recommend stakeholders conduct a Disease Risk Analysis for orangutan translocation, and improve pathogen surveillance and mitigation measures to decrease the likelihood of potential outbreaks. We also suggest refocusing conservation efforts on alternatives to wild-to-wild translocation including mitigating human-orangutan interactions, enforcing laws and protecting orangutan habitats to conserve orangutans in situ.

@article{wichSavingTapanuliOrangutan2021,
	title = {Saving the {Tapanuli} orangutan requires zero losses},
	volume = {55},
	issn = {0030-6053},
	url = {https://www.cambridge.org/core/article/saving-the-tapanuli-orangutan-requires-zero-losses/A15D19A23A59E086488B7AA53D67EFE8},
	doi = {10.1017/S0030605320001052},
	number = {1},
	journal = {Oryx},
	author = {Wich, Serge and Meijaard, Erik},
	year = {2021},
	note = {Edition: 2021/01/11},
	pages = {10--11},
}

@book{wichConservationTechnology2021,
	title = {Conservation {Technology}},
	isbn = {0-19-259084-7},
	publisher = {Oxford University Press},
	author = {Wich, Serge A and Piel, Alex K},
	year = {2021},
}

@article{bonninModellingLandscapeConnectivity2020,
	title = {Modelling landscape connectivity change for chimpanzee conservation in {Tanzania}},
	volume = {252},
	issn = {0006-3207},
	journal = {Biological Conservation},
	author = {Bonnin, Noémie and Stewart, Fiona A and Wich, Serge A and Pintea, Lilian and Jantz, Samuel M and Dickson, Rebecca and Bellis, Joe and Chitayat, Adrienne and Ingram, Rebecca and Moore, Richard J},
	year = {2020},
	pages = {108816},
}

@article{burivalovaDoesBiodiversityBenefit2020,
	title = {Does biodiversity benefit when the logging stops? {An} analysis of conservation risks and opportunities in active versus inactive logging concessions in {Borneo}},
	volume = {241},
	issn = {0006-3207},
	url = {http://www.sciencedirect.com/science/article/pii/S0006320719309085},
	doi = {10.1016/j.biocon.2019.108369},
	abstract = {The island of Borneo is a biodiversity hotspot of global importance that continues to suffer from one of the highest deforestation rates in the tropics. Selective logging concessions overlay a third of the remaining natural forests in the Indonesian part of Borneo, but many of these concessions have become inactive in recent years. Whereas the cessation of logging could be beneficial to biodiversity, the absence of a logging company's presence in the forest could also leave the concession open to deforestation by other actors. Using remote sensing analyses, we evaluate 1) whether inactive concessions are more likely to suffer from deforestation than active ones, 2) the possible reasons why concessions become inactive, and 3) which inactive concessions hold the most potential for biodiversity conservation, if protected from deforestation. Our analysis shows that, counterintuitively, inactive concessions overall suffer a higher rate of forest loss than active ones. We find that small concession size and high elevation are correlated with inactive status. We identified several inactive concessions that, if maintained as natural forest, could significantly contribute to biodiversity conservation, as exemplified by their importance to two umbrella species: Bornean orangutan (Critically Endangered) and Sunda clouded leopard (Vulnerable). Because timber operations in other tropical regions are likely to experience similar cycles of activity and inactivity, the fate of inactive timber concessions and the opportunities they create for conservation deserve much greater attention from conservation scientists and practitioners.},
	journal = {Biological Conservation},
	author = {Burivalova, Zuzana and Game, Edward T. and Wahyudi, Bambang and {Ruslandi} and Rifqi, Mohamad and MacDonald, Ewan and Cushman, Samuel and Voigt, Maria and Wich, Serge and Wilcove, David S.},
	month = jan,
	year = {2020},
	pages = {108369},
}

The island of Borneo is a biodiversity hotspot of global importance that continues to suffer from one of the highest deforestation rates in the tropics. Selective logging concessions overlay a third of the remaining natural forests in the Indonesian part of Borneo, but many of these concessions have become inactive in recent years. Whereas the cessation of logging could be beneficial to biodiversity, the absence of a logging company's presence in the forest could also leave the concession open to deforestation by other actors. Using remote sensing analyses, we evaluate 1) whether inactive concessions are more likely to suffer from deforestation than active ones, 2) the possible reasons why concessions become inactive, and 3) which inactive concessions hold the most potential for biodiversity conservation, if protected from deforestation. Our analysis shows that, counterintuitively, inactive concessions overall suffer a higher rate of forest loss than active ones. We find that small concession size and high elevation are correlated with inactive status. We identified several inactive concessions that, if maintained as natural forest, could significantly contribute to biodiversity conservation, as exemplified by their importance to two umbrella species: Bornean orangutan (Critically Endangered) and Sunda clouded leopard (Vulnerable). Because timber operations in other tropical regions are likely to experience similar cycles of activity and inactivity, the fate of inactive timber concessions and the opportunities they create for conservation deserve much greater attention from conservation scientists and practitioners.

@article{chuaConservationSocialSciences2020,
	title = {Conservation and the social sciences: {Beyond} critique and co‐optation. {A} case study from orangutan conservation},
	volume = {2},
	issn = {2575-8314},
	number = {1},
	journal = {People and Nature},
	author = {Chua, Liana and Harrison, Mark E and Fair, Hannah and Milne, Sol and Palmer, Alexandra and Rubis, June and Thung, Paul and Wich, Serge and Büscher, Bram and Cheyne, Susan M},
	year = {2020},
	pages = {42--60},
}

@article{junkerSevereLackEvidence2020,
	title = {A {Severe} {Lack} of {Evidence} {Limits} {Effective} {Conservation} of the {World}'s {Primates}},
	issn = {0006-3568},
	url = {https://doi.org/10.1093/biosci/biaa082},
	doi = {10.1093/biosci/biaa082},
	abstract = {Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a scientific framework. The Conservation Evidence project has summarized thousands of studies testing conservation interventions and compiled these as synopses for various habitats and taxa. In the present article, we analyzed the interventions assessed in the primate synopsis and compared these with other taxa. We found that despite intensive efforts to study primates and the extensive threats they face, less than 1\% of primate studies evaluated conservation effectiveness. The studies often lacked quantitative data, failed to undertake postimplementation monitoring of populations or individuals, or implemented several interventions at once. Furthermore, the studies were biased toward specific taxa, geographic regions, and interventions. We describe barriers for testing primate conservation interventions and propose actions to improve the conservation evidence base to protect this endangered and globally important taxon.},
	urldate = {2020-08-27},
	journal = {BioScience},
	author = {Junker, Jessica and Petrovan, Silviu O and Arroyo-RodrÍguez, Victor and Boonratana, Ramesh and Byler, Dirck and Chapman, Colin A and Chetry, Dilip and Cheyne, Susan M and Cornejo, Fanny M and CortÉs-Ortiz, Liliana and Cowlishaw, Guy and Christie, Alec P and Crockford, Catherine and Torre, Stella De La and De Melo, Fabiano R and Fan, P and Grueter, Cyril C and GuzmÁn-Caro, Diana C and Heymann, Eckhard W and Herbinger, Ilka and Hoang, Minh D and Horwich, Robert H and Humle, Tatyana and Ikemeh, Rachel A and Imong, Inaoyom S and Jerusalinsky, Leandro and Johnson, Steig E and Kappeler, Peter M and Kierulff, Maria CecÍlia M and KonÉ, Inza and Kormos, Rebecca and Le, Khac Q and Li, Baoguo and Marshall, Andrew J and Meijaard, Erik and Mittermeier, Russel A and Muroyama, Yasuyuki and Neugebauer, Eleonora and Orth, Lisa and Palacios, Erwin and Papworth, Sarah K and Plumptre, Andrew J and Rawson, Ben M and Refisch, Johannes and Ratsimbazafy, Jonah and Roos, Christian and Setchell, Joanna M and Smith, Rebecca K and Sop, Tene and Schwitzer, Christoph and Slater, Kerry and Strum, Shirley C and Sutherland, William J and Talebi, MaurÍcio and Wallis, Janette and Wich, Serge and Williamson, Elizabeth A and Wittig, Roman M and KÜhl, Hjalmar S},
	year = {2020},
}

Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a scientific framework. The Conservation Evidence project has summarized thousands of studies testing conservation interventions and compiled these as synopses for various habitats and taxa. In the present article, we analyzed the interventions assessed in the primate synopsis and compared these with other taxa. We found that despite intensive efforts to study primates and the extensive threats they face, less than 1% of primate studies evaluated conservation effectiveness. The studies often lacked quantitative data, failed to undertake postimplementation monitoring of populations or individuals, or implemented several interventions at once. Furthermore, the studies were biased toward specific taxa, geographic regions, and interventions. We describe barriers for testing primate conservation interventions and propose actions to improve the conservation evidence base to protect this endangered and globally important taxon.

@article{knotDNABarcodingNematodes2020,
	title = {{DNA} {Barcoding} of {Nematodes} {Using} the {MinION}},
	volume = {8},
	issn = {2296-701X},
	shorttitle = {{MinION} {DNA} barcoding of nematodes},
	url = {https://www.frontiersin.org/article/10.3389/fevo.2020.00100},
	doi = {10.3389/fevo.2020.00100},
	abstract = {Many nematode species are parasitic and threaten the health of plants and animals, including humans, on a global scale. Advances in DNA sequencing techniques have allowed for the rapid and accurate identification of many organisms including nematodes. However, the steps taken from sample collection in the field to molecular analysis and identification can take many days and depend on access to both immovable equipment and a specialized laboratory. Here, we present a protocol to genetically identify nematodes using 18S SSU rRNA sequencing using the MinION, a portable third generation sequencer, and proof that it is possible to perform all the molecular preparations on a fully portable molecular biology lab – the Bentolab. We show that both parasitic and free-living nematode species (Anisakis simplex, Panagrellus redivivus, Turbatrix aceti, and Caenorhabditis elegans) can be identified with a 96–100\% accuracy compared to Sanger sequencing, requiring only 10–15 min of sequencing. This protocol is an essential first step toward genetically identifying nematodes in the field from complex natural environments (such as feces, soil, or marine sediments). This increased accessibility could in turn improve global information of nematode presence and distribution, aiding near-real-time global biomonitoring.},
	language = {English},
	number = {100},
	journal = {Frontiers in Ecology and Evolution},
	author = {Knot, Ineke E. and Zouganelis, George D. and Weedall, Gareth D. and Wich, Serge A. and Rae, Robbie},
	month = apr,
	year = {2020},
}

Many nematode species are parasitic and threaten the health of plants and animals, including humans, on a global scale. Advances in DNA sequencing techniques have allowed for the rapid and accurate identification of many organisms including nematodes. However, the steps taken from sample collection in the field to molecular analysis and identification can take many days and depend on access to both immovable equipment and a specialized laboratory. Here, we present a protocol to genetically identify nematodes using 18S SSU rRNA sequencing using the MinION, a portable third generation sequencer, and proof that it is possible to perform all the molecular preparations on a fully portable molecular biology lab – the Bentolab. We show that both parasitic and free-living nematode species (Anisakis simplex, Panagrellus redivivus, Turbatrix aceti, and Caenorhabditis elegans) can be identified with a 96–100% accuracy compared to Sanger sequencing, requiring only 10–15 min of sequencing. This protocol is an essential first step toward genetically identifying nematodes in the field from complex natural environments (such as feces, soil, or marine sediments). This increased accessibility could in turn improve global information of nematode presence and distribution, aiding near-real-time global biomonitoring.

@article{lauranceTapanuliOrangutanEndangered2020,
	title = {Tapanuli orangutan endangered by {Sumatran} hydropower scheme},
	issn = {2397-334X},
	url = {https://doi.org/10.1038/s41559-020-1263-x},
	doi = {10.1038/s41559-020-1263-x},
	journal = {Nature Ecology \& Evolution},
	author = {Laurance, William F. and Wich, Serge A. and Onrizal, Onrizal and Fredriksson, Gabriella and Usher, Graham and Santika, Truly and Byler, Dirck and Mittermeier, Russell and Kormos, Rebecca and Williamson, Elizabeth A. and Meijaard, Erik},
	month = jul,
	year = {2020},
}

@article{mesquitaMeasuringDisturbanceSwift2020,
	title = {Measuring disturbance at a swift breeding colonies due to the visual aspects of a drone: a quasi-experiment study},
	issn = {2396-9814},
	url = {https://doi.org/10.1093/cz/zoaa038},
	doi = {10.1093/cz/zoaa038},
	abstract = {There is a growing body of research indicating that drones can disturb animals. However, it is usually unclear whether the disturbance is due to visual or auditory cues. Here, we examined the effect of drone flights on the behaviour of great dusky swifts Cypseloides senex and white-collared swifts Streptoprocne zonaris in two breeding sites where drone noise was obscured by environmental noise from waterfalls and any disturbance must be largely visual. We performed 12 experimental flights with a multirotor drone at different vertical, horizontal and diagonal distances from the colonies. From all flights, 17\% caused \<1\% of birds to temporarily abandon the breeding site, 50\% caused half to abandon and 33\% caused more than half to abandon. We showed that the diagonal distance explained 98.9\% of the variability of the disturbance percentage and while at distances greater than 50 m the disturbance percentage does not exceed 20\%, at less than 40 m the disturbance percentage increase to above 60\%. We recommend that flights with a multirotor drone during the breeding period should be conducted at a distance of \> 50 m and that recreational flights should be discouraged or conducted at larger distances (e.g. 100 m) in nesting birds areas such as waterfalls, canyons and caves.},
	urldate = {2020-07-16},
	journal = {Current Zoology},
	author = {Mesquita, Geison P and Rodríguez-Teijeiro, José D and Wich, Serge A and Mulero-Pázmány, Margarita},
	year = {2020},
}

There is a growing body of research indicating that drones can disturb animals. However, it is usually unclear whether the disturbance is due to visual or auditory cues. Here, we examined the effect of drone flights on the behaviour of great dusky swifts Cypseloides senex and white-collared swifts Streptoprocne zonaris in two breeding sites where drone noise was obscured by environmental noise from waterfalls and any disturbance must be largely visual. We performed 12 experimental flights with a multirotor drone at different vertical, horizontal and diagonal distances from the colonies. From all flights, 17% caused <1% of birds to temporarily abandon the breeding site, 50% caused half to abandon and 33% caused more than half to abandon. We showed that the diagonal distance explained 98.9% of the variability of the disturbance percentage and while at distances greater than 50 m the disturbance percentage does not exceed 20%, at less than 40 m the disturbance percentage increase to above 60%. We recommend that flights with a multirotor drone during the breeding period should be conducted at a distance of > 50 m and that recreational flights should be discouraged or conducted at larger distances (e.g. 100 m) in nesting birds areas such as waterfalls, canyons and caves.

@article{muscarellaGlobalAbundanceTree2020,
	title = {The global abundance of tree palms},
	volume = {29},
	issn = {1466-822X},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/geb.13123},
	doi = {10.1111/geb.13123},
	abstract = {Abstract Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co-occurring non-palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in {\textgreater}80\% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long-term climate stability. Life-form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non-tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above-ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.},
	number = {9},
	journal = {Global Ecology and Biogeography},
	author = {Muscarella, Robert and Emilio, Thaise and Phillips, Oliver L. and Lewis, Simon L. and Slik, Ferry and Baker, William J. and Couvreur, Thomas L. P. and Eiserhardt, Wolf L. and Svenning, Jens-Christian and Affum-Baffoe, Kofi and Aiba, Shin-Ichiro and de Almeida, Everton C. and de Almeida, Samuel S. and de Oliveira, Edmar Almeida and Álvarez-Dávila, Esteban and Alves, Luciana F. and Alvez-Valles, Carlos Mariano and Carvalho, Fabrício Alvim and Guarin, Fernando Alzate and Andrade, Ana and Aragão, Luis E. O. C. and Murakami, Alejandro Araujo and Arroyo, Luzmila and Ashton, Peter S. and Corredor, Gerardo A. Aymard and Baker, Timothy R. and de Camargo, Plinio Barbosa and Barlow, Jos and Bastin, Jean-François and Bengone, Natacha Nssi and Berenguer, Erika and Berry, Nicholas and Blanc, Lilian and Böhning-Gaese, Katrin and Bonal, Damien and Bongers, Frans and Bradford, Matt and Brambach, Fabian and Brearley, Francis Q. and Brewer, Steven W. and Camargo, Jose L. C. and Campbell, David G. and Castilho, Carolina V. and Castro, Wendeson and Catchpole, Damien and Cerón Martínez, Carlos E. and Chen, Shengbin and Chhang, Phourin and Cho, Percival and Chutipong, Wanlop and Clark, Connie and Collins, Murray and Comiskey, James A. and Medina, Massiel Nataly Corrales and Costa, Flávia R. C. and Culmsee, Heike and David-Higuita, Heriberto and Davidar, Priya and del Aguila-Pasquel, Jhon and Derroire, Géraldine and Di Fiore, Anthony and Van Do, Tran and Doucet, Jean-Louis and Dourdain, Aurélie and Drake, Donald R. and Ensslin, Andreas and Erwin, Terry and Ewango, Corneille E. N. and Ewers, Robert M. and Fauset, Sophie and Feldpausch, Ted R. and Ferreira, Joice and Ferreira, Leandro Valle and Fischer, Markus and Franklin, Janet and Fredriksson, Gabriella M. and Gillespie, Thomas W. and Gilpin, Martin and Gonmadje, Christelle and Gunatilleke, Arachchige Upali Nimal and Hakeem, Khalid Rehman and Hall, Jefferson S. and Hamer, Keith C. and Harris, David J. and Harrison, Rhett D. and Hector, Andrew and Hemp, Andreas and Herault, Bruno and Pizango, Carlos Gabriel Hidalgo and Coronado, Eurídice N. Honorio and Hubau, Wannes and Hussain, Mohammad Shah and Ibrahim, Faridah-Hanum and Imai, Nobuo and Joly, Carlos A. and Joseph, Shijo and K, Anitha and Kartawinata, Kuswata and Kassi, Justin and Killeen, Timothy J. and Kitayama, Kanehiro and Klitgård, Bente Bang and Kooyman, Robert and Labrière, Nicolas and Larney, Eileen and Laumonier, Yves and Laurance, Susan G. and Laurance, William F. and Lawes, Michael J. and Levesley, Aurora and Lisingo, Janvier and Lovejoy, Thomas and Lovett, Jon C. and Lu, Xinghui and Lykke, Anne Mette and Magnusson, William E. and Mahayani, Ni Putu Diana and Malhi, Yadvinder and Mansor, Asyraf and Peña, Jose Luis Marcelo and Marimon-Junior, Ben H. and Marshall, Andrew R. and Melgaco, Karina and Bautista, Casimiro Mendoza and Mihindou, Vianet and Millet, Jérôme and Milliken, William and Mohandass, D. and Mendoza, Abel Lorenzo Monteagudo and Mugerwa, Badru and Nagamasu, Hidetoshi and Nagy, Laszlo and Seuaturien, Naret and Nascimento, Marcelo T. and Neill, David A. and Neto, Luiz Menini and Nilus, Rueben and Vargas, Mario Percy Núñez and Nurtjahya, Eddy and de Araújo, R. Nazaré O. and Onrizal, Onrizal and Palacios, Walter A. and Palacios-Ramos, Sonia and Parren, Marc and Paudel, Ekananda and Morandi, Paulo S. and Pennington, R. Toby and Pickavance, Georgia and Pipoly III, John J. and Pitman, Nigel C. A. and Poedjirahajoe, Erny and Poorter, Lourens and Poulsen, John R. and Rama Chandra Prasad, P. and Prieto, Adriana and Puyravaud, Jean-Philippe and Qie, Lan and Quesada, Carlos A. and Ramírez-Angulo, Hirma and Razafimahaimodison, Jean Claude and Reitsma, Jan Meindert and Requena-Rojas, Edilson J. and Correa, Zorayda Restrepo and Rodriguez, Carlos Reynel and Roopsind, Anand and Rovero, Francesco and Rozak, Andes and Lleras, Agustín Rudas and Rutishauser, Ervan and Rutten, Gemma and Punchi-Manage, Ruwan and Salomão, Rafael P. and Van Sam, Hoang and Sarker, Swapan Kumar and Satdichanh, Manichanh and Schietti, Juliana and Schmitt, Christine B. and Marimon, Beatriz Schwantes and Senbeta, Feyera and Nath Sharma, Lila and Sheil, Douglas and Sierra, Rodrigo and Silva-Espejo, Javier E. and Silveira, Marcos and Sonké, Bonaventure and Steininger, Marc K. and Steinmetz, Robert and Stévart, Tariq and Sukumar, Raman and Sultana, Aisha and Sunderland, Terry C. H. and Suresh, Hebbalalu Satyanarayana and Tang, Jianwei and Tanner, Edmund and ter Steege, Hans and Terborgh, John W. and Theilade, Ida and Timberlake, Jonathan and Torres-Lezama, Armando and Umunay, Peter and Uriarte, María and Gamarra, Luis Valenzuela and van de Bult, Martin and van der Hout, Peter and Martinez, Rodolfo Vasquez and Vieira, Ima Célia Guimarães and Vieira, Simone A. and Vilanova, Emilio and Cayo, Jeanneth Villalobos and Wang, Ophelia and Webb, Campbell O. and Webb, Edward L. and White, Lee and Whitfeld, Timothy J. S. and Wich, Serge and Willcock, Simon and Wiser, Susan K. and Young, Kenneth R. and Zakaria, Rahmad and Zang, Runguo and Zartman, Charles E. and Zo-Bi, Irié Casimir and Balslev, Henrik},
	year = {2020},
	pages = {1495--1514},
}

Abstract Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co-occurring non-palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in \textgreater80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long-term climate stability. Life-form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non-tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above-ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.

@article{rafiqSpatialTemporalOverlaps2020,
	title = {Spatial and temporal overlaps between leopards ({Panthera} pardus) and their competitors in the {African} large predator guild},
	issn = {1469-7998},
	journal = {Journal of Zoology},
	author = {Rafiq, K and Hayward, MW and Wilson, AM and Meloro, C and Jordan, NR and Wich, SA and McNutt, JW and Golabek, KA},
	year = {2020},
}

@article{rafiqScentmarkingStrategiesSolitary2020,
	title = {Scent-marking strategies of a solitary carnivore: boundary and road scent marking in the leopard},
	volume = {161},
	issn = {0003-3472},
	url = {http://www.sciencedirect.com/science/article/pii/S000334721930418X},
	doi = {10.1016/j.anbehav.2019.12.016},
	abstract = {Scent marking, where individuals deposit signals on objects in the environment, is a common form of chemical signalling in mammals and is thought to play a critical role in maintaining social organization within wide-ranging, spatially dispersed populations. Senders, however, can incur scent-marking costs through mark production, time investment in patrolling and depositing/maintaining mark sites, and increased risk of detection by predators and prey. To mitigate these costs, senders can adapt spatial patterns of scent marking to increase the probabilities of their scent marks being encountered by intended receivers. Relatively little, however, is known of the spatial scent-marking placements of many wide-ranging carnivore species, with most studies focusing on scent mark form and function. Here, we used detailed observational data collected from over 7 years of following individual leopards, Panthera pardus, and high-resolution GPS radiocollar data to investigate the spatial placements of scent marks within a leopard population in northern Botswana. We found that male leopards within our study area had a boundary scent-marking strategy, investing more in maintaining marking sites in peripheral areas of their home range. We also found that leopards scent-marked over four times as frequently and investigated over three times as frequently when travelling on roads than when travelling along natural routes, suggesting that roads may function as key locations for olfactory information. Compared to leopards from less productive ecosystems, such as the Kalahari, our results (1) suggest that leopards can be highly flexible in their marking strategies, with strategies impacted by the surrounding environment, and (2) provide evidence that human modifications of the environment now play an important role in facilitating social cohesion within this solitary carnivore.},
	journal = {Animal Behaviour},
	author = {Rafiq, Kasim and Jordan, Neil R. and Meloro, Carlo and Wilson, Alan M. and Hayward, Matthew W. and Wich, Serge A. and McNutt, John W.},
	month = mar,
	year = {2020},
	pages = {115--126},
}

Scent marking, where individuals deposit signals on objects in the environment, is a common form of chemical signalling in mammals and is thought to play a critical role in maintaining social organization within wide-ranging, spatially dispersed populations. Senders, however, can incur scent-marking costs through mark production, time investment in patrolling and depositing/maintaining mark sites, and increased risk of detection by predators and prey. To mitigate these costs, senders can adapt spatial patterns of scent marking to increase the probabilities of their scent marks being encountered by intended receivers. Relatively little, however, is known of the spatial scent-marking placements of many wide-ranging carnivore species, with most studies focusing on scent mark form and function. Here, we used detailed observational data collected from over 7 years of following individual leopards, Panthera pardus, and high-resolution GPS radiocollar data to investigate the spatial placements of scent marks within a leopard population in northern Botswana. We found that male leopards within our study area had a boundary scent-marking strategy, investing more in maintaining marking sites in peripheral areas of their home range. We also found that leopards scent-marked over four times as frequently and investigated over three times as frequently when travelling on roads than when travelling along natural routes, suggesting that roads may function as key locations for olfactory information. Compared to leopards from less productive ecosystems, such as the Kalahari, our results (1) suggest that leopards can be highly flexible in their marking strategies, with strategies impacted by the surrounding environment, and (2) provide evidence that human modifications of the environment now play an important role in facilitating social cohesion within this solitary carnivore.

@article{rothGroupingBehaviorSumatran2020,
	title = {Grouping behavior of {Sumatran} orangutans ({Pongo} abelii) and {Tapanuli} orangutans ({Pongo} tapanuliensis) living in forest with low fruit abundance},
	volume = {82},
	issn = {0275-2565},
	number = {5},
	journal = {American Journal of Primatology},
	author = {Roth, Tom S and Rianti, Puji and Fredriksson, Gabriella M and Wich, Serge A and Nowak, Matthew G},
	year = {2020},
	pages = {e23123},
}

@article{shermanEnvisioningFutureBornean2020,
	title = {Envisioning a future for {Bornean} orangutans: {Conservation} impacts of action plan implementation and recommendations for improved population outcomes},
	volume = {21},
	issn = {1412-033X},
	number = {2},
	journal = {Biodiversitas},
	author = {Sherman, Julie and Ancrenaz, Marc and Voigt, Maria and Oram, Felicity and Santika, Truly and Wich, SA and Meijaard, Erik},
	year = {2020},
	pages = {465--477},
}

@article{burkeOptimizingObservingStrategies2019,
	title = {Optimizing observing strategies for monitoring animals using drone-mounted thermal infrared cameras},
	volume = {40},
	issn = {0143-1161},
	number = {2},
	journal = {International Journal of Remote Sensing},
	author = {Burke, Claire and Rashman, Maisie and Wich, Serge and Symons, Andy and Theron, Cobus and Longmore, Steve},
	year = {2019},
	pages = {439--467},
}

@article{burkeSuccessfulObservationOrangutans2019,
	title = {Successful observation of orangutans in the wild with thermal-equipped drones},
	issn = {2291-3467},
	number = {ja},
	journal = {Journal of Unmanned Vehicle Systems},
	author = {Burke, Claire and Rashman, Maisie Frances and Longmore, Steve N and McAree, Owen and Glover-Kapfer, Paul and Ancrenaz, Marc and Wich, Serge},
	year = {2019},
}

@article{burkeThermalDronesSafeReliable2019,
	title = {Thermal-{Drones} as a {Safe} and {Reliable} {Method} for {Detecting} {Subterranean} {Peat} {Fires}},
	volume = {3},
	number = {1},
	journal = {Drones},
	author = {Burke, Claire and Wich, Serge and Kusin, Kitso and McAree, Owen and Harrison, Mark E and Ripoll, Bernat and Ermiasi, Yunsiska and Mulero-Pázmány, Margarita and Longmore, Steve},
	year = {2019},
	pages = {23},
}

@article{carvalhoGlobalRiskAssessment2019,
	title = {A global risk assessment of primates under climate and land use/cover scenarios},
	issn = {1354-1013},
	journal = {Global change biology},
	author = {Carvalho, Joana S and Graham, Bruce and Rebelo, Hugo and Bocksberger, Gaëlle and Meyer, Christoph FJ and Wich, Serge and Kühl, Hjalmar S},
	year = {2019},
	pages = {3163--3178},
}

@article{descalsOilPalmElaeis2019,
	title = {Oil {Palm} ({Elaeis} guineensis) {Mapping} with {Details}: {Smallholder} versus {Industrial} {Plantations} and their {Extent} in {Riau}, {Sumatra}},
	volume = {11},
	issn = {2072-4292},
	url = {https://www.mdpi.com/2072-4292/11/21/2590},
	number = {21},
	journal = {Remote Sensing},
	author = {Descals, Adrià and Szantoi, Zoltan and Meijaard, Erik and Sutikno, Harsono and Rindanata, Guruh and Wich, Serge},
	year = {2019},
	pages = {2590},
}

@article{hambrechtDetectingPoachersDrones2019,
	title = {Detecting ‘poachers’ with drones: {Factors} influencing the probability of detection with {TIR} and {RGB} imaging in miombo woodlands, {Tanzania}},
	volume = {233},
	issn = {0006-3207},
	journal = {Biological Conservation},
	author = {Hambrecht, Leonard and Brown, Richard P and Piel, Alex K and Wich, Serge A},
	year = {2019},
	pages = {109--117},
}

@article{plumptreAreWeCapturing2019,
	title = {Are {We} {Capturing} {Faunal} {Intactness}? {A} {Comparison} of {Intact} {Forest} {Landscapes} and the “{Last} of the {Wild} in {Each} {Ecoregion}”},
	volume = {2},
	issn = {2624-893X},
	shorttitle = {Are we capturing faunal intactness?},
	url = {https://www.frontiersin.org/article/10.3389/ffgc.2019.00024},
	doi = {10.3389/ffgc.2019.00024},
	abstract = {Ecologically intact ecosystems are becoming increasingly limited on the planet, making their identification and conservation an important priority. Intact forest landscapes (IFLs) are defined as forests that are mainly free of significant anthropogenic degradation and at least 500 km2 in size. Here we define a new metric, the Last of the Wild in each Ecoregion (LWE), as a preliminary scoping of the most intact parts of each ecoregion. IFL and LWE are approaches among a broad family of techniques to mapping ecological integrity at the global scale. Although both implicitly include species integrity as a dimension of intactness, this is inferred rather than directly measured. We assessed whether LWE areas or IFL were better at capturing species where they are most abundant using species distribution data for a set of forest species for which range-wide data were available and human activity limits the range. We found that IFL and LWE methods identified areas where species we assessed are either absent or at too low an abundance to be ecologically functional. As such many IFL/LWE polygons did not have intact fauna. We also show that 54.7\% of the terrestrial realm (excluding Antarctica) has at least one species recorded as extinct and that two thirds of IFL/LWE areas overlap with areas where species have gone extinct in the past 500 years. The results show that neither IFL or LWE identifies areas of ecologically intact fauna adequately, underscoring a strong need to obtain additional site-level survey data to confirm faunal intactness.},
	language = {English},
	number = {24},
	journal = {Frontiers in Forests and Global Change},
	author = {Plumptre, Andrew J. and Baisero, Daniele and Jędrzejewski, Włodzimierz and Kühl, Hjalmar and Maisels, Fiona and Ray, Justina C. and Sanderson, Eric W. and Strindberg, Samantha and Voigt, Maria and Wich, Serge},
	month = jun,
	year = {2019},
}

Ecologically intact ecosystems are becoming increasingly limited on the planet, making their identification and conservation an important priority. Intact forest landscapes (IFLs) are defined as forests that are mainly free of significant anthropogenic degradation and at least 500 km2 in size. Here we define a new metric, the Last of the Wild in each Ecoregion (LWE), as a preliminary scoping of the most intact parts of each ecoregion. IFL and LWE are approaches among a broad family of techniques to mapping ecological integrity at the global scale. Although both implicitly include species integrity as a dimension of intactness, this is inferred rather than directly measured. We assessed whether LWE areas or IFL were better at capturing species where they are most abundant using species distribution data for a set of forest species for which range-wide data were available and human activity limits the range. We found that IFL and LWE methods identified areas where species we assessed are either absent or at too low an abundance to be ecologically functional. As such many IFL/LWE polygons did not have intact fauna. We also show that 54.7% of the terrestrial realm (excluding Antarctica) has at least one species recorded as extinct and that two thirds of IFL/LWE areas overlap with areas where species have gone extinct in the past 500 years. The results show that neither IFL or LWE identifies areas of ecologically intact fauna adequately, underscoring a strong need to obtain additional site-level survey data to confirm faunal intactness.

@article{rafiqTouristPhotographsScalable2019,
	title = {Tourist photographs as a scalable framework for wildlife monitoring in protected areas},
	volume = {29},
	issn = {0960-9822},
	url = {http://www.sciencedirect.com/science/article/pii/S0960982219306268},
	doi = {10.1016/j.cub.2019.05.056},
	abstract = {Summary Protected areas are critical to conservation efforts in the face of rapid biodiversity declines [1]. Yet the resources for conservation are often limited and shared amongst many competing priorities [2]. As a consequence, even basic monitoring surveys are absent within most protected areas [3]. Although a range of wildlife monitoring methods exist, considerable focused survey effort is often required to yield accurate and precise estimates [4]. This makes monitoring difficult to sustain or replicate, limiting access to the data required for evidence-based conservation decisions. Citizen-scientists have been proposed as an important complement to the finite resources available for basic monitoring within protected areas [5]; however, the full potential of this approach has yet to be realised. Wildlife tourists and guides are especially focussed on encountering and photographing fauna and flora, yet the data collected in these efforts is rarely harnessed for conservation monitoring within protected areas. A detailed understanding of photographic tourism’s potential role in wildlife monitoring has been lacking, but is essential for the development of new tools to harness the data being collected through tourism. Here, we demonstrate that tourist-contributed data can aid wildlife monitoring in protected areas by providing population estimates of large carnivores comparable to those from traditional survey methods. Our approach could capitalize upon the immense number of wildlife photographs being taken daily as part of the global {\textgreater} 30-billion USD, wildlife-based tourism industry.},
	number = {14},
	journal = {Current Biology},
	author = {Rafiq, Kasim and Bryce, Caleb M. and Rich, Lindsey N. and Coco, Carli and Miller, David A. W. and Meloro, Carlo and Wich, Serge A. and McNutt, John W. and Hayward, Matthew W.},
	month = jul,
	year = {2019},
	pages = {R681--R682},
}

Summary Protected areas are critical to conservation efforts in the face of rapid biodiversity declines [1]. Yet the resources for conservation are often limited and shared amongst many competing priorities [2]. As a consequence, even basic monitoring surveys are absent within most protected areas [3]. Although a range of wildlife monitoring methods exist, considerable focused survey effort is often required to yield accurate and precise estimates [4]. This makes monitoring difficult to sustain or replicate, limiting access to the data required for evidence-based conservation decisions. Citizen-scientists have been proposed as an important complement to the finite resources available for basic monitoring within protected areas [5]; however, the full potential of this approach has yet to be realised. Wildlife tourists and guides are especially focussed on encountering and photographing fauna and flora, yet the data collected in these efforts is rarely harnessed for conservation monitoring within protected areas. A detailed understanding of photographic tourism’s potential role in wildlife monitoring has been lacking, but is essential for the development of new tools to harness the data being collected through tourism. Here, we demonstrate that tourist-contributed data can aid wildlife monitoring in protected areas by providing population estimates of large carnivores comparable to those from traditional survey methods. Our approach could capitalize upon the immense number of wildlife photographs being taken daily as part of the global \textgreater 30-billion USD, wildlife-based tourism industry.

@article{rafiqSpatiotemporalFactorsImpacting2019,
	title = {Spatio‐temporal factors impacting encounter occurrences between leopards and other large {African} predators},
	issn = {0952-8369},
	journal = {Journal of Zoology},
	author = {Rafiq, Kasim and Jordan, NR and Wilson, Alan M and McNutt, JW and Hayward, MW and Meloro, C and Wich, SA and Golabek, KA},
	year = {2019},
}

@article{spaanThermalInfraredImaging2019,
	title = {Thermal {Infrared} {Imaging} from {Drones} {Offers} a {Major} {Advance} for {Spider} {Monkey} {Surveys}},
	volume = {3},
	number = {2},
	journal = {Drones},
	author = {Spaan, Denise and Burke, Claire and McAree, Owen and Aureli, Filippo and Rangel-Rivera, Coral E and Hutschenreiter, Anja and Longmore, Steve N and McWhirter, Paul R and Wich, Serge A},
	year = {2019},
	pages = {34},
}

@article{wichTapanuliOrangutanStatus2019,
	title = {The {Tapanuli} orangutan: {Status}, threats and steps for improved conservation},
	journal = {Conservation Science and Practice},
	author = {Wich, S.A. and Fredriksson, G. and Usher, G. and Kuhl, H. and Nowak, M.},
	year = {2019},
}

@book{wichConservationDrones2018,
	title = {Conservation {Drones}},
	isbn = {978-0-19-878761-7},
	publisher = {Oxford University Press},
	author = {Wich, S. A and Koh, Lian Pin},
	year = {2018},
}

@article{bonninAssessmentChimpanzeeNest2018,
	title = {Assessment of {Chimpanzee} {Nest} {Detectability} in {Drone}-{Acquired} {Images}},
	volume = {2},
	number = {2},
	journal = {Drones},
	author = {Bonnin, Noémie and van Andel, Alexander C and Kerby, Jeffrey T and Piel, Alex K and Pintea, Lilian and Wich, Serge A},
	year = {2018},
	pages = {17},
}

@inproceedings{burkeAddressingEnvironmentalAtmospheric2018,
	title = {Addressing environmental and atmospheric challenges for capturing high-precision thermal infrared data in the field of astro-ecology},
	volume = {10709},
	publisher = {SPIE},
	author = {Burke, Claire and Rashman, Maisie F. and McAree, Owen and Hambrecht, Leonard and Longmore, Steve N. and Piel, Alex K. and Wich, Serge A.},
	year = {2018},
	pages = {8},
}

@article{estradaPrimatesPerilSignificance2018,
	title = {Primates in peril: the significance of {Brazil}, {Madagascar}, {Indonesia} and the {Democratic} {Republic} of the {Congo} for global primate conservation},
	volume = {6},
	issn = {2167-8359},
	url = {https://doi.org/10.7717/peerj.4869},
	doi = {10.7717/peerj.4869},
	abstract = {Primates occur in 90 countries, but four—Brazil, Madagascar, Indonesia, and the Democratic Republic of the Congo (DRC)—harbor 65\% of the world’s primate species (439) and 60\% of these primates are Threatened, Endangered, or Critically Endangered (IUCN Red List of Threatened Species 2017-3). Considering their importance for global primate conservation, we examine the anthropogenic pressures each country is facing that place their primate populations at risk. Habitat loss and fragmentation are main threats to primates in Brazil, Madagascar, and Indonesia. However, in DRC hunting for the commercial bushmeat trade is the primary threat. Encroachment on primate habitats driven by local and global market demands for food and non-food commodities hunting, illegal trade, the proliferation of invasive species, and human and domestic-animal borne infectious diseases cause habitat loss, population declines, and extirpation. Modeling agricultural expansion in the 21st century for the four countries under a worst-case-scenario, showed a primate range contraction of 78\% for Brazil, 72\% for Indonesia, 62\% for Madagascar, and 32\% for DRC. These pressures unfold in the context of expanding human populations with low levels of development. Weak governance across these four countries may limit effective primate conservation planning. We examine landscape and local approaches to effective primate conservation policies and assess the distribution of protected areas and primates in each country. Primates in Brazil and Madagascar have 38\% of their range inside protected areas, 17\% in Indonesia and 14\% in DRC, suggesting that the great majority of primate populations remain vulnerable. We list the key challenges faced by the four countries to avert primate extinctions now and in the future. In the short term, effective law enforcement to stop illegal hunting and illegal forest destruction is absolutely key. Long-term success can only be achieved by focusing local and global public awareness, and actively engaging with international organizations, multinational businesses and consumer nations to reduce unsustainable demands on the environment. Finally, the four primate range countries need to ensure that integrated, sustainable land-use planning for economic development includes the maintenance of biodiversity and intact, functional natural ecosystems.},
	journal = {PeerJ},
	author = {Estrada, Alejandro and Garber, Paul A. and Mittermeier, Russell A. and Wich, Serge and Gouveia, Sidney and Dobrovolski, Ricardo and Nekaris, K. A. I. and Nijman, Vincent and Rylands, Anthony B. and Maisels, Fiona and Williamson, Elizabeth A. and Bicca-Marques, Julio and Fuentes, Agustin and Jerusalinsky, Leandro and Johnson, Steig and Rodrigues de Melo, Fabiano and Oliveira, Leonardo and Schwitzer, Christoph and Roos, Christian and Cheyne, Susan M. and Martins Kierulff, Maria Cecilia and Raharivololona, Brigitte and Talebi, Mauricio and Ratsimbazafy, Jonah and Supriatna, Jatna and Boonratana, Ramesh and Wedana, Made and Setiawan, Arif},
	month = jun,
	year = {2018},
	pages = {e4869},
}

Primates occur in 90 countries, but four—Brazil, Madagascar, Indonesia, and the Democratic Republic of the Congo (DRC)—harbor 65% of the world’s primate species (439) and 60% of these primates are Threatened, Endangered, or Critically Endangered (IUCN Red List of Threatened Species 2017-3). Considering their importance for global primate conservation, we examine the anthropogenic pressures each country is facing that place their primate populations at risk. Habitat loss and fragmentation are main threats to primates in Brazil, Madagascar, and Indonesia. However, in DRC hunting for the commercial bushmeat trade is the primary threat. Encroachment on primate habitats driven by local and global market demands for food and non-food commodities hunting, illegal trade, the proliferation of invasive species, and human and domestic-animal borne infectious diseases cause habitat loss, population declines, and extirpation. Modeling agricultural expansion in the 21st century for the four countries under a worst-case-scenario, showed a primate range contraction of 78% for Brazil, 72% for Indonesia, 62% for Madagascar, and 32% for DRC. These pressures unfold in the context of expanding human populations with low levels of development. Weak governance across these four countries may limit effective primate conservation planning. We examine landscape and local approaches to effective primate conservation policies and assess the distribution of protected areas and primates in each country. Primates in Brazil and Madagascar have 38% of their range inside protected areas, 17% in Indonesia and 14% in DRC, suggesting that the great majority of primate populations remain vulnerable. We list the key challenges faced by the four countries to avert primate extinctions now and in the future. In the short term, effective law enforcement to stop illegal hunting and illegal forest destruction is absolutely key. Long-term success can only be achieved by focusing local and global public awareness, and actively engaging with international organizations, multinational businesses and consumer nations to reduce unsustainable demands on the environment. Finally, the four primate range countries need to ensure that integrated, sustainable land-use planning for economic development includes the maintenance of biodiversity and intact, functional natural ecosystems.

@techreport{meijaardOilPalmBiodiversity2018,
	address = {Gland, Switzerland},
	title = {Oil palm and biodiversity. {A} situation analysis by the {IUCN} {Oil} {Palm} {Task} {Force}},
	institution = {IUCN},
	author = {Meijaard, E and Garcia-Ulloa, John and Sheil, D and Wich, S. A. and Carlson, K. and Juffe-Bignoli, D. and Brooks, T. M.},
	year = {2018},
}

@article{meijaardOrangutanPopulationsAre2018,
	title = {Orangutan populations are certainly not increasing in the wild},
	volume = {28},
	issn = {0960-9822},
	url = {https://doi.org/10.1016/j.cub.2018.09.052},
	doi = {10.1016/j.cub.2018.09.052},
	number = {21},
	urldate = {2018-11-05},
	journal = {Current Biology},
	author = {Meijaard, Erik and Sherman, Julie and Ancrenaz, Marc and Wich, Serge A. and Santika, Truly and Voigt, Maria},
	year = {2018},
	pages = {R1241--R1242},
}

@inproceedings{rashmanAdaptingThermalinfraredTechnology2018,
	title = {Adapting thermal-infrared technology and astronomical techniques for use in conservation biology},
	volume = {10709},
	publisher = {SPIE},
	author = {Rashman, Maisie F. and Steele, Iain A. and Burke, Claire and Longmore, Steve N. and Wich, Serge},
	year = {2018},
	pages = {10},
}

@article{slikPhylogeneticClassificationWorlds2018,
	title = {Phylogenetic classification of the world’s tropical forests},
	url = {http://www.pnas.org/content/pnas/early/2018/01/31/1714977115.full.pdf},
	doi = {10.1073/pnas.1714977115},
	abstract = {Identifying and explaining regional differences in tropical forest dynamics, structure, diversity, and composition are critical for anticipating region-specific responses to global environmental change. Floristic classifications are of fundamental importance for these efforts. Here we provide a global tropical forest classification that is explicitly based on community evolutionary similarity, resulting in identification of five major tropical forest regions and their relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. African and American forests are grouped, reflecting their former western Gondwanan connection, while Indo-Pacific forests range from eastern Africa and Madagascar to Australia and the Pacific. The connection between northern-hemisphere Asian and American forests is confirmed, while Dry forests are identified as a single tropical biome.Knowledge about the biogeographic affinities of the world’s tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world’s tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.},
	journal = {Proceedings of the National Academy of Sciences},
	author = {Slik, J. W. Ferry and Franklin, Janet and Arroyo-Rodríguez, Víctor and Field, Richard and Aguilar, Salomon and Aguirre, Nikolay and Ahumada, Jorge and Aiba, Shin-Ichiro and Alves, Luciana F. and K, Anitha and Avella, Andres and Mora, Francisco and Aymard C., Gerardo A. and Báez, Selene and Balvanera, Patricia and Bastian, Meredith L. and Bastin, Jean-François and Bellingham, Peter J. and van den Berg, Eduardo and da Conceição Bispo, Polyanna and Boeckx, Pascal and Boehning-Gaese, Katrin and Bongers, Frans and Boyle, Brad and Brambach, Fabian and Brearley, Francis Q. and Brown, Sandra and Chai, Shauna-Lee and Chazdon, Robin L. and Chen, Shengbin and Chhang, Phourin and Chuyong, George and Ewango, Corneille and Coronado, Indiana M. and Cristóbal-Azkarate, Jurgi and Culmsee, Heike and Damas, Kipiro and Dattaraja, H. S. and Davidar, Priya and DeWalt, Saara J. and Din, Hazimah and Drake, Donald R. and Duque, Alvaro and Durigan, Giselda and Eichhorn, Karl and Eler, Eduardo Schmidt and Enoki, Tsutomu and Ensslin, Andreas and Fandohan, Adandé Belarmain and Farwig, Nina and Feeley, Kenneth J. and Fischer, Markus and Forshed, Olle and Garcia, Queila Souza and Garkoti, Satish Chandra and Gillespie, Thomas W. and Gillet, Jean-Francois and Gonmadje, Christelle and Granzow-de la Cerda, Iñigo and Griffith, Daniel M. and Grogan, James and Hakeem, Khalid Rehman and Harris, David J. and Harrison, Rhett D. and Hector, Andy and Hemp, Andreas and Homeier, Jürgen and Hussain, M. Shah and Ibarra-Manríquez, Guillermo and Hanum, I. Faridah and Imai, Nobuo and Jansen, Patrick A. and Joly, Carlos Alfredo and Joseph, Shijo and Kartawinata, Kuswata and Kearsley, Elizabeth and Kelly, Daniel L. and Kessler, Michael and Killeen, Timothy J. and Kooyman, Robert M. and Laumonier, Yves and Laurance, Susan G. and Laurance, William F. and Lawes, Michael J. and Letcher, Susan G. and Lindsell, Jeremy and Lovett, Jon and Lozada, Jose and Lu, Xinghui and Lykke, Anne Mette and Mahmud, Khairil Bin and Mahayani, Ni Putu Diana and Mansor, Asyraf and Marshall, Andrew R. and Martin, Emanuel H. and Calderado Leal Matos, Darley and Meave, Jorge A. and Melo, Felipe P. L. and Mendoza, Zhofre Huberto Aguirre and Metali, Faizah and Medjibe, Vincent P. and Metzger, Jean Paul and Metzker, Thiago and Mohandass, D. and Munguía-Rosas, Miguel A. and Muñoz, Rodrigo and Nurtjahy, Eddy and de Oliveira, Eddie Lenza and {Onrizal} and Parolin, Pia and Parren, Marc and Parthasarathy, N. and Paudel, Ekananda and Perez, Rolando and Pérez-García, Eduardo A. and Pommer, Ulf and Poorter, Lourens and Qi, Lan and Piedade, Maria Teresa F. and Pinto, José Roberto Rodrigues and Poulsen, Axel Dalberg and Poulsen, John R. and Powers, Jennifer S. and Prasad, Rama Chandra and Puyravaud, Jean-Philippe and Rangel, Orlando and Reitsma, Jan and Rocha, Diogo S. B. and Rolim, Samir and Rovero, Francesco and Rozak, Andes and Ruokolainen, Kalle and Rutishauser, Ervan and Rutten, Gemma and Mohd. Said, Mohd. Nizam and Saiter, Felipe Z. and Saner, Philippe and Santos, Braulio and dos Santos, João Roberto and Sarker, Swapan Kumar and Schmitt, Christine B. and Schoengart, Jochen and Schulze, Mark and Sheil, Douglas and Sist, Plinio and Souza, Alexandre F. and Spironello, Wilson Roberto and Sposito, Tereza and Steinmetz, Robert and Stevart, Tariq and Suganuma, Marcio Seiji and Sukri, Rahayu and Sultana, Aisha and Sukumar, Raman and Sunderland, Terry and {Supriyadi} and Suresh, H. S. and Suzuki, Eizi and Tabarelli, Marcelo and Tang, Jianwei and Tanner, Ed V. J. and Targhetta, Natalia and Theilade, Ida and Thomas, Duncan and Timberlake, Jonathan and de Morisson Valeriano, Márcio and van Valkenburg, Johan and Van Do, Tran and Van Sam, Hoang and Vandermeer, John H. and Verbeeck, Hans and Vetaas, Ole Reidar and Adekunle, Victor and Vieira, Simone A. and Webb, Campbell O. and Webb, Edward L. and Whitfeld, Timothy and Wich, Serge and Williams, John and Wiser, Susan and Wittmann, Florian and Yang, Xiaobo and Adou Yao, C. Yves and Yap, Sandra L. and Zahawi, Rakan A. and Zakaria, Rahmad and Zang, Runguo},
	year = {2018},
}

Identifying and explaining regional differences in tropical forest dynamics, structure, diversity, and composition are critical for anticipating region-specific responses to global environmental change. Floristic classifications are of fundamental importance for these efforts. Here we provide a global tropical forest classification that is explicitly based on community evolutionary similarity, resulting in identification of five major tropical forest regions and their relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. African and American forests are grouped, reflecting their former western Gondwanan connection, while Indo-Pacific forests range from eastern Africa and Madagascar to Australia and the Pacific. The connection between northern-hemisphere Asian and American forests is confirmed, while Dry forests are identified as a single tropical biome.Knowledge about the biogeographic affinities of the world’s tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world’s tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.

@article{speharOrangutansVentureOut2018,
	title = {Orangutans venture out of the rainforest and into the {Anthropocene}},
	volume = {4},
	url = {http://advances.sciencemag.org/content/advances/4/6/e1701422.full.pdf},
	doi = {10.1126/sciadv.1701422},
	abstract = {Conservation benefits from understanding how adaptability and threat interact to determine a taxon’s vulnerability. Recognizing how interactions with humans have shaped taxa such as the critically endangered orangutan (Pongo spp.) offers insights into this relationship. Orangutans are viewed as icons of wild nature, and most efforts to prevent their extinction have focused on protecting minimally disturbed habitat, with limited success. We synthesize fossil, archeological, genetic, and behavioral evidence to demonstrate that at least 70,000 years of human influence have shaped orangutan distribution, abundance, and ecology and will likely continue to do so in the future. Our findings indicate that orangutans are vulnerable to hunting but appear flexible in response to some other human activities. This highlights the need for a multifaceted, landscape-level approach to orangutan conservation that leverages sound policy and cooperation among government, private sector, and community stakeholders to prevent hunting, mitigate human-orangutan conflict, and preserve and reconnect remaining natural forests. Broad cooperation can be encouraged through incentives and strategies that focus on the common interests and concerns of different stakeholders. Orangutans provide an illustrative example of how acknowledging the long and pervasive influence of humans can improve strategies to preserve biodiversity in the Anthropocene.},
	number = {6},
	journal = {Science Advances},
	author = {Spehar, Stephanie N. and Sheil, Douglas and Harrison, Terry and Louys, Julien and Ancrenaz, Marc and Marshall, Andrew J. and Wich, Serge A. and Bruford, Michael W. and Meijaard, Erik},
	year = {2018},
	pages = {e1701422},
}

Conservation benefits from understanding how adaptability and threat interact to determine a taxon’s vulnerability. Recognizing how interactions with humans have shaped taxa such as the critically endangered orangutan (Pongo spp.) offers insights into this relationship. Orangutans are viewed as icons of wild nature, and most efforts to prevent their extinction have focused on protecting minimally disturbed habitat, with limited success. We synthesize fossil, archeological, genetic, and behavioral evidence to demonstrate that at least 70,000 years of human influence have shaped orangutan distribution, abundance, and ecology and will likely continue to do so in the future. Our findings indicate that orangutans are vulnerable to hunting but appear flexible in response to some other human activities. This highlights the need for a multifaceted, landscape-level approach to orangutan conservation that leverages sound policy and cooperation among government, private sector, and community stakeholders to prevent hunting, mitigate human-orangutan conflict, and preserve and reconnect remaining natural forests. Broad cooperation can be encouraged through incentives and strategies that focus on the common interests and concerns of different stakeholders. Orangutans provide an illustrative example of how acknowledging the long and pervasive influence of humans can improve strategies to preserve biodiversity in the Anthropocene.

@article{stronaSmallRoomCompromise2018,
	title = {Small room for compromise between oil palm cultivation and primate conservation in {Africa}},
	volume = {115},
	url = {http://www.pnas.org/content/pnas/early/2018/08/07/1804775115.full.pdf},
	doi = {10.1073/pnas.1804775115},
	abstract = {Although oil palm cultivation represents an important source of income for many tropical countries, its future expansion is a primary threat to tropical forests and biodiversity. In this context, and especially in regions where industrial palm oil production is still emerging, identifying “areas of compromise,” that is, areas with high productivity and low biodiversity importance, could be a unique opportunity to reconcile conservation and economic growth. We applied this approach to Africa, by combining data on oil palm suitability with primate distribution, diversity, and vulnerability. We found that such areas of compromise are very rare throughout the continent (0.13 Mha), and that large-scale expansion of oil palm cultivation in Africa will have unavoidable, negative effects on primates.Despite growing awareness about its detrimental effects on tropical biodiversity, land conversion to oil palm continues to increase rapidly as a consequence of global demand, profitability, and the income opportunity it offers to producing countries. Although most industrial oil palm plantations are located in Southeast Asia, it is argued that much of their future expansion will occur in Africa. We assessed how this could affect the continent’s primates by combining information on oil palm suitability and current land use with primate distribution, diversity, and vulnerability. We also quantified the potential impact of large-scale oil palm cultivation on primates in terms of range loss under different expansion scenarios taking into account future demand, oil palm suitability, human accessibility, carbon stock, and primate vulnerability. We found a high overlap between areas of high oil palm suitability and areas of high conservation priority for primates. Overall, we found only a few small areas where oil palm could be cultivated in Africa with a low impact on primates (3.3 Mha, including all areas suitable for oil palm). These results warn that, consistent with the dramatic effects of palm oil cultivation on biodiversity in Southeast Asia, reconciling a large-scale development of oil palm in Africa with primate conservation will be a great challenge.},
	number = {35},
	journal = {Proceedings of the National Academy of Sciences},
	author = {Strona, Giovanni and Stringer, Simon D. and Vieilledent, Ghislain and Szantoi, Zoltan and Garcia-Ulloa, John and A. Wich, Serge},
	year = {2018},
	pages = {8811--8816},
}

Although oil palm cultivation represents an important source of income for many tropical countries, its future expansion is a primary threat to tropical forests and biodiversity. In this context, and especially in regions where industrial palm oil production is still emerging, identifying “areas of compromise,” that is, areas with high productivity and low biodiversity importance, could be a unique opportunity to reconcile conservation and economic growth. We applied this approach to Africa, by combining data on oil palm suitability with primate distribution, diversity, and vulnerability. We found that such areas of compromise are very rare throughout the continent (0.13 Mha), and that large-scale expansion of oil palm cultivation in Africa will have unavoidable, negative effects on primates.Despite growing awareness about its detrimental effects on tropical biodiversity, land conversion to oil palm continues to increase rapidly as a consequence of global demand, profitability, and the income opportunity it offers to producing countries. Although most industrial oil palm plantations are located in Southeast Asia, it is argued that much of their future expansion will occur in Africa. We assessed how this could affect the continent’s primates by combining information on oil palm suitability and current land use with primate distribution, diversity, and vulnerability. We also quantified the potential impact of large-scale oil palm cultivation on primates in terms of range loss under different expansion scenarios taking into account future demand, oil palm suitability, human accessibility, carbon stock, and primate vulnerability. We found a high overlap between areas of high oil palm suitability and areas of high conservation priority for primates. Overall, we found only a few small areas where oil palm could be cultivated in Africa with a low impact on primates (3.3 Mha, including all areas suitable for oil palm). These results warn that, consistent with the dramatic effects of palm oil cultivation on biodiversity in Southeast Asia, reconciling a large-scale development of oil palm in Africa with primate conservation will be a great challenge.

@article{thapaCountingCrocodilesSky2018,
	title = {Counting crocodiles from the sky: {Monitoring} the critically endangered gharial ({Gavialis} gangeticus) population with an unmanned aerial vehicle ({UAV})},
	issn = {2291-3467},
	url = {https://doi.org/10.1139/juvs-2017-0026},
	doi = {10.1139/juvs-2017-0026},
	urldate = {2018-02-12},
	journal = {Journal of Unmanned Vehicle Systems},
	author = {Thapa, Gokarna Jung and Thapa, Kanchan and Thapa, Ramesh and Jnawali, Shant Raj and Wich, Serge and Poudyal, Laxman Prasad and Karki, Suraj},
	year = {2018},
}

@article{voigtGlobalDemandNatural2018,
	title = {Global {Demand} for {Natural} {Resources} {Eliminated} {More} {Than} 100,000 {Bornean} {Orangutans}},
	volume = {28},
	issn = {0960-9822},
	url = {http://dx.doi.org/10.1016/j.cub.2018.01.053},
	doi = {10.1016/j.cub.2018.01.053},
	urldate = {2018-02-15},
	journal = {Current Biology},
	author = {Voigt, Maria and Wich, Serge A. and Ancrenaz, Marc and Meijaard, Erik and Abram, Nicola and Banes, Graham L. and Campbell-Smith, Gail and d’Arcy, Laura J. and Delgado, Roberto A. and Erman, Andi and Gaveau, David and Goossens, Benoit and Heinicke, Stefanie and Houghton, Max and Husson, Simon J. and Leiman, Ashley and Sanchez, Karmele Llano and Makinuddin, Niel and Marshall, Andrew J. and Meididit, Ari and Miettinen, Jukka and Mundry, Roger and {Musnanda} and {Nardiyono} and Nurcahyo, Anton and Odom, Kisar and Panda, Adventus and Prasetyo, Didik and Priadjati, Aldrianto and {Purnomo} and Rafiastanto, Andjar and Russon, Anne E. and Santika, Truly and Sihite, Jamartin and Spehar, Stephanie and Struebig, Matthew and Sulbaran-Romero, Enrique and Tjiu, Albertus and Wells, Jessie and Wilson, Kerrie A. and Kühl, Hjalmar S.},
	year = {2018},
	pages = {761--769},
}

@incollection{wichClassifyingLandCover2018,
	address = {Santa Fe, New Mexico},
	title = {Classifying land cover on very high resolution drone-acquired orthomosaics},
	booktitle = {New geospatial approaches to the anthropological sciences},
	publisher = {School of Advances Research Press},
	author = {Wich, S. and Koh, Lian Pin and Szantoi, Zoltan},
	editor = {Anemone, RL and Conroy, Glenn C.},
	year = {2018},
	pages = {121--136},
}

@article{duffyLocationLocationLocation2017,
	title = {Location, location, location: {Considerations} when using lighweight drones in challenging environments},
	doi = {10.1002/rse2.58},
	journal = {Remote Sensing in Ecology and Conservation},
	author = {Duffy, J. P. and Cunliffe, A. M. and DeBell, L. and Sandbrook, Chris and Wich, S. A. and Shutler, J. D. and Myers-Smith, I. H. and Varela, M. R. and Anderson, K.},
	year = {2017},
}

@article{estradaImpendingExtinctionCrisis2017,
	title = {Impending extinction crisis of the world’s primates: {Why} primates matter},
	volume = {3},
	doi = {10.1126/sciadv.1600946},
	abstract = {Nonhuman primates, our closest biological relatives, play important roles in the livelihoods, cultures, and religions of many societies and offer unique insights into human evolution, biology, behavior, and the threat of emerging diseases. They are an essential component of tropical biodiversity, contributing to forest regeneration and ecosystem health. Current information shows the existence of 504 species in 79 genera distributed in the Neotropics, mainland Africa, Madagascar, and Asia. Alarmingly, {\textasciitilde}60\% of primate species are now threatened with extinction and {\textasciitilde}75\% have declining populations. This situation is the result of escalating anthropogenic pressures on primates and their habitats—mainly global and local market demands, leading to extensive habitat loss through the expansion of industrial agriculture, large-scale cattle ranching, logging, oil and gas drilling, mining, dam building, and the construction of new road networks in primate range regions. Other important drivers are increased bushmeat hunting and the illegal trade of primates as pets and primate body parts, along with emerging threats, such as climate change and anthroponotic diseases. Often, these pressures act in synergy, exacerbating primate population declines. Given that primate range regions overlap extensively with a large, and rapidly growing, human population characterized by high levels of poverty, global attention is needed immediately to reverse the looming risk of primate extinctions and to attend to local human needs in sustainable ways. Raising global scientific and public awareness of the plight of the world’s primates and the costs of their loss to ecosystem health and human society is imperative.\%U http://advances.sciencemag.org/content/advances/3/1/e1600946.full.pdf},
	number = {1},
	journal = {Science Advances},
	author = {Estrada, Alejandro and Garber, Paul A. and Rylands, Anthony B. and Roos, Christian and Fernandez-Duque, Eduardo and Di Fiore, Anthony and Nekaris, K. Anne-Isola and Nijman, Vincent and Heymann, Eckhard W. and Lambert, Joanna E. and Rovero, Francesco and Barelli, Claudia and Setchell, Joanna M. and Gillespie, Thomas R. and Mittermeier, Russell A. and Arregoitia, Luis Verde and de Guinea, Miguel and Gouveia, Sidney and Dobrovolski, Ricardo and Shanee, Sam and Shanee, Noga and Boyle, Sarah A. and Fuentes, Agustin and MacKinnon, Katherine C. and Amato, Katherine R. and Meyer, Andreas L. S. and Wich, Serge and Sussman, Robert W. and Pan, Ruliang and Kone, Inza and Li, Baoguo},
	year = {2017},
	pages = {e1600946},
}

Nonhuman primates, our closest biological relatives, play important roles in the livelihoods, cultures, and religions of many societies and offer unique insights into human evolution, biology, behavior, and the threat of emerging diseases. They are an essential component of tropical biodiversity, contributing to forest regeneration and ecosystem health. Current information shows the existence of 504 species in 79 genera distributed in the Neotropics, mainland Africa, Madagascar, and Asia. Alarmingly, ~60% of primate species are now threatened with extinction and ~75% have declining populations. This situation is the result of escalating anthropogenic pressures on primates and their habitats—mainly global and local market demands, leading to extensive habitat loss through the expansion of industrial agriculture, large-scale cattle ranching, logging, oil and gas drilling, mining, dam building, and the construction of new road networks in primate range regions. Other important drivers are increased bushmeat hunting and the illegal trade of primates as pets and primate body parts, along with emerging threats, such as climate change and anthroponotic diseases. Often, these pressures act in synergy, exacerbating primate population declines. Given that primate range regions overlap extensively with a large, and rapidly growing, human population characterized by high levels of poverty, global attention is needed immediately to reverse the looming risk of primate extinctions and to attend to local human needs in sustainable ways. Raising global scientific and public awareness of the plight of the world’s primates and the costs of their loss to ecosystem health and human society is imperative.%U http://advances.sciencemag.org/content/advances/3/1/e1600946.full.pdf

@article{leendertzEbolaGreatApes2017,
	title = {Ebola in great apes – current knowledge, possibilities for vaccination, and implications for conservation and human health},
	volume = {47},
	issn = {0305-1838},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/mam.12082},
	doi = {10.1111/mam.12082},
	abstract = {Abstract Ebola virus disease (EVD) is a threat to human health and to the survival of African great apes. The disease has led to major population declines in chimpanzees Pan troglodytes and gorillas Gorilla gorilla, and infected great apes play an important role as sources of human EVD outbreaks. The threat posed by EVD raises the question whether vaccination of wild apes is an effective strategy to reduce the occurrence and impact of this disease. We review the current knowledge about EVD in great apes and document the link between outbreaks in apes and in humans, mainly via bushmeat consumption. We discuss the need for control strategies, such as vaccination, and describe aspects of primate behaviour, virus biology, vaccine composition, and vaccination principles that need to be considered when making management decisions about great ape vaccination. Finally, we identify gaps in the understanding of Ebola ecology and highlight surveillance and research that can aid the survival of great apes and reduce human exposure to Ebola virus. The severe impact of EVD indicates the need for efficient monitoring and, ultimately, control of Ebola. However, the unknown reservoir and unpredictable emergence of Ebola, the elusive nature of great apes, and the lack of licensed and suitable vaccines represent major hurdles for such control. Public education about zoonotic diseases and monitoring of great ape health are both important strategies. Experts should also discuss the feasibility of developing safe vaccines that can be delivered efficiently to large populations of elusive wild apes in their natural remote habitats. This review provides a platform for further interdisciplinary discussions, so that management plans can be discussed and adjusted according to possible future changes in the development, availability and cost of vaccines, the status of EVD, knowledge about Ebola ecology, and opinion on wildlife vaccination.},
	number = {2},
	journal = {Mammal Review},
	author = {Leendertz, Siv Aina J. and Wich, Serge A. and Ancrenaz, Marc and Bergl, Richard A. and Gonder, Mary K. and Humle, Tatyana and Leendertz, Fabian H.},
	year = {2017},
	pages = {98--111},
}

Abstract Ebola virus disease (EVD) is a threat to human health and to the survival of African great apes. The disease has led to major population declines in chimpanzees Pan troglodytes and gorillas Gorilla gorilla, and infected great apes play an important role as sources of human EVD outbreaks. The threat posed by EVD raises the question whether vaccination of wild apes is an effective strategy to reduce the occurrence and impact of this disease. We review the current knowledge about EVD in great apes and document the link between outbreaks in apes and in humans, mainly via bushmeat consumption. We discuss the need for control strategies, such as vaccination, and describe aspects of primate behaviour, virus biology, vaccine composition, and vaccination principles that need to be considered when making management decisions about great ape vaccination. Finally, we identify gaps in the understanding of Ebola ecology and highlight surveillance and research that can aid the survival of great apes and reduce human exposure to Ebola virus. The severe impact of EVD indicates the need for efficient monitoring and, ultimately, control of Ebola. However, the unknown reservoir and unpredictable emergence of Ebola, the elusive nature of great apes, and the lack of licensed and suitable vaccines represent major hurdles for such control. Public education about zoonotic diseases and monitoring of great ape health are both important strategies. Experts should also discuss the feasibility of developing safe vaccines that can be delivered efficiently to large populations of elusive wild apes in their natural remote habitats. This review provides a platform for further interdisciplinary discussions, so that management plans can be discussed and adjusted according to possible future changes in the development, availability and cost of vaccines, the status of EVD, knowledge about Ebola ecology, and opinion on wildlife vaccination.

@article{longmoreAdaptingAstronomicalSource2017,
	title = {Adapting astronomical source detection software to help detect animals in thermal images obtained by unmanned aerial systems},
	volume = {38},
	journal = {International Journal of Remote Sensing},
	author = {Longmore, SN and Collins, RP and Pfeifer, S and Fox, SE and Mulero-Pazmany, M and Bezombes, F and Goodwin, A and Ovelar, M and Knapen, JH and Wich, SA},
	year = {2017},
	pages = {2623--2638},
}

@article{naterMorphometricBehavioralGenomic2017,
	title = {Morphometric, {Behavioral}, and {Genomic} {Evidence} for a {New} {Orangutan} {Species}},
	issn = {0960-9822},
	url = {http://dx.doi.org/10.1016/j.cub.2017.09.047},
	doi = {10.1016/j.cub.2017.09.047},
	urldate = {2017-11-02},
	journal = {Current Biology},
	author = {Nater, Alexander and Mattle-Greminger, Maja P. and Nurcahyo, Anton and Nowak, Matthew G. and de Manuel, Marc and Desai, Tariq and Groves, Colin and Pybus, Marc and Sonay, Tugce Bilgin and Roos, Christian and Lameira, Adriano R. and Wich, Serge A. and Askew, James and Davila-Ross, Marina and Fredriksson, Gabriella and de Valles, Guillem and Casals, Ferran and Prado-Martinez, Javier and Goossens, Benoit and Verschoor, Ernst J. and Warren, Kristin S. and Singleton, Ian and Marques, David A. and Pamungkas, Joko and Perwitasari-Farajallah, Dyah and Rianti, Puji and Tuuga, Augustine and Gut, Ivo G. and Gut, Marta and Orozco-terWengel, Pablo and van Schaik, Carel P. and Bertranpetit, Jaume and Anisimova, Maria and Scally, Aylwyn and Marques-Bonet, Tomas and Meijaard, Erik and Krützen, Michael},
	year = {2017},
}

@article{nowakPongoTapanuliensis2017,
	title = {Pongo tapanuliensis},
	doi = {10.2305/IUCN},
	journal = {The IUCN Red List of Threatened Species},
	author = {Nowak, M.G. and Rianti, P. and Wich, S.A. and Meijaard, E. and Fredriksson, G.},
	year = {2017},
	pages = {e.T120588639A120588662},
}

@article{santikaFirstIntegrativeTrend2017,
	title = {First integrative trend analysis for a great ape species in {Borneo}},
	volume = {7},
	issn = {2045-2322},
	url = {http://dx.doi.org/10.1038/s41598-017-04435-9},
	doi = {10.1038/s41598-017-04435-9},
	abstract = {For many threatened species the rate and drivers of population decline are difficult to assess accurately: species’ surveys are typically restricted to small geographic areas, are conducted over short time periods, and employ a wide range of survey protocols. We addressed methodological challenges for assessing change in the abundance of an endangered species. We applied novel methods for integrating field and interview survey data for the critically endangered Bornean orangutan (Pongo pygmaeus), allowing a deeper understanding of the species’ persistence through time. Our analysis revealed that Bornean orangutan populations have declined at a rate of 25\% over the last 10 years. Survival rates of the species are lowest in areas with intermediate rainfall, where complex interrelations between soil fertility, agricultural productivity, and human settlement patterns influence persistence. These areas also have highest threats from human-wildlife conflict. Survival rates are further positively associated with forest extent, but are lower in areas where surrounding forest has been recently converted to industrial agriculture. Our study highlights the urgency of determining specific management interventions needed in different locations to counter the trend of decline and its associated drivers.},
	number = {1},
	journal = {Scientific Reports},
	author = {Santika, Truly and Ancrenaz, Marc and Wilson, Kerrie A. and Spehar, Stephanie and Abram, Nicola and Banes, Graham L. and Campbell-Smith, Gail and Curran, Lisa and d’Arcy, Laura and Delgado, Roberto A. and Erman, Andi and Goossens, Benoit and Hartanto, Herlina and Houghton, Max and Husson, Simon J. and Kühl, Hjalmar S. and Lackman, Isabelle and Leiman, Ashley and Llano Sanchez, Karmele and Makinuddin, Niel and Marshall, Andrew J. and Meididit, Ari and Mengersen, Kerrie and {Musnanda} and {Nardiyono} and Nurcahyo, Anton and Odom, Kisar and Panda, Adventus and Prasetyo, Didik and {Purnomo} and Rafiastanto, Andjar and Raharjo, Slamet and Ratnasari, Dessy and Russon, Anne E. and Santana, Adi H. and Santoso, Eddy and Sapari, Iman and Sihite, Jamartin and Suyoko, Ahmat and Tjiu, Albertus and Utami-Atmoko, Sri Suci and van Schaik, Carel P. and Voigt, Maria and Wells, Jessie and Wich, Serge A. and Willems, Erik P. and Meijaard, Erik},
	month = jul,
	year = {2017},
	pages = {1--8},
}

For many threatened species the rate and drivers of population decline are difficult to assess accurately: species’ surveys are typically restricted to small geographic areas, are conducted over short time periods, and employ a wide range of survey protocols. We addressed methodological challenges for assessing change in the abundance of an endangered species. We applied novel methods for integrating field and interview survey data for the critically endangered Bornean orangutan (Pongo pygmaeus), allowing a deeper understanding of the species’ persistence through time. Our analysis revealed that Bornean orangutan populations have declined at a rate of 25% over the last 10 years. Survival rates of the species are lowest in areas with intermediate rainfall, where complex interrelations between soil fertility, agricultural productivity, and human settlement patterns influence persistence. These areas also have highest threats from human-wildlife conflict. Survival rates are further positively associated with forest extent, but are lower in areas where surrounding forest has been recently converted to industrial agriculture. Our study highlights the urgency of determining specific management interventions needed in different locations to counter the trend of decline and its associated drivers.

@article{singletonPongoAbeliiErrata2017,
	title = {Pongo abelii (errata version published in 2018).},
	journal = {The IUCN Red List of Threatened Species 2017},
	author = {Singleton, I. and Wich, S.A. and Nowak, M. and Usher, G. and Utami-Atmoko, S.S.},
	year = {2017},
	pages = {e.T121097935A123797627.},
}

@article{szantoiMappingOrangutanHabitat2017,
	title = {Mapping orangutan habitat and agricultural areas using {Landsat} {OLI} imagery augmented with unmanned aircraft system aerial photography},
	issn = {0143-1161},
	url = {http://dx.doi.org/10.1080/01431161.2017.1280638},
	doi = {10.1080/01431161.2017.1280638},
	journal = {International Journal of Remote Sensing},
	author = {Szantoi, Zoltan and Smith, Scot E. and Strona, Giovanni and Koh, Lian Pin and Wich, Serge A.},
	year = {2017},
	pages = {1--15},
}

@techreport{utamiatmokoOrangutanPopulationHabitat2017,
	address = {Apple Valley, MN.},
	title = {Orangutan {Population} and {Habitat} {Viability} {Assessment}: {Final} {Report}},
	institution = {IUCN/SSC Conservation Breeding Specialist Group},
	author = {Utami Atmoko, S. and Traylor-Holzer, K. and Rifqi, M. A. and Siregar, P.G. and Achmad, B. and Priadjati, A. and Husson, S. and Wich, S. and Hadisiswoyo, P. and Saputra, F. and Campbell-Smith, G. and Kuncoro, P. and Russon, A. and Voigt, M. and Santika, T. and Nowak, M. and Singleton, I., I. Sapari and Meididit, A. and Chandradewi, B., D.S. Ripoll Capilla and {Ermayanti} and Lees, C.M.},
	year = {2017},
}

@article{wichPreliminaryAssessmentUsing2016,
	title = {A preliminary assessment of using conservation drones for {Sumatran} orang-utan ({Pongo} abelii) distribution and density},
	volume = {4},
	issn = {2291-3467},
	url = {http://dx.doi.org/10.1139/juvs-2015-0015},
	doi = {10.1139/juvs-2015-0015},
	urldate = {2016-01-13},
	journal = {Journal of Unmanned Vehicle Systems},
	author = {Wich, Serge A. and Dellatore, David and Houghton, Max and Ardi, Rio and Koh, Lian Pin},
	year = {2016},
	pages = {45--52},
}

@article{ancrenazPongoPygmaeusErrata2016,
	title = {Pongo pygmaeus (errata version published in 2018).},
	journal = {The IUCN Red List of Threatened Species 2016},
	author = {Ancrenaz, M. and Gumal, M. and Marshall, A.J. and Meijaard, E. and Wich, S.A. and Husson, S.},
	year = {2016},
	pages = {e.T17975A123809220.},
}

@techreport{ancrenazPalmOilParadox2016,
	title = {Palm {Oil} {Paradox}: {Sustainable} {Solutions} to {Save} the {Great} {Apes} {Great} {Apes}},
	author = {Ancrenaz, M. and Meijaard, E. and Wich, S. and Simery, J.},
	year = {2016},
	note = {Edition: 2nd},
}

@incollection{faHuntingPrimateConservation2016,
	title = {Hunting and primate conservation},
	isbn = {0-19-870338-4},
	booktitle = {An introduction to primate conservation},
	publisher = {Oxford University Press, Oxford, UK},
	author = {Fa, John E and Tagg, Nikki},
	editor = {Wich, S.A. and Marshall, A. J.},
	year = {2016},
	pages = {143--156},
}

@incollection{korstjensPrimatesClimateChange2016,
	address = {New York, US},
	title = {Primates and climate change: a review of current knowledge},
	isbn = {0-19-100850-8},
	booktitle = {An {Introduction} to {Primate} {Conservation}},
	publisher = {Oxford University Press},
	author = {Korstjens, Amanda H and Hillyer, Alison P},
	editor = {Wich, S. A. and Marshall, A. J.},
	year = {2016},
	pages = {175--192},
}

@article{lameiraVocalFoldControl2016,
	title = {Vocal fold control beyond the species-specific repertoire in an orang-utan},
	volume = {6},
	url = {http://dx.doi.org/10.1038/srep30315},
	doi = {10.1038/srep30315},
	journal = {Scientific Reports},
	author = {Lameira, Adriano R. and Hardus, Madeleine E. and Mielke, Alexander and Wich, Serge A. and Shumaker, Robert W.},
	year = {2016},
	pages = {30315},
}

@article{marshallGreatApesFresh2016,
	title = {Great apes: {Fresh} strategies to save orangutans},
	volume = {535},
	issn = {0028-0836},
	url = {http://dx.doi.org/10.1038/535493a},
	doi = {10.1038/535493a},
	number = {7613},
	journal = {Nature},
	author = {Marshall, Andrew J. and Wich, Serge and Ancrenaz, Marc},
	year = {2016},
	pages = {493--493},
}

@incollection{meijaardRoleMultifunctionalLandscapes2016,
	address = {New York},
	title = {The role of multifunctional landscapes in primate conservation},
	booktitle = {An introduction to primate conservation},
	publisher = {Oxford University Press},
	author = {Meijaard, Erik},
	editor = {Wich, S. A. and Marshall, A. J.},
	year = {2016},
	pages = {205--218},
}

@article{nilssonCommunityMotivationsEngage2016,
	title = {Community motivations to engage in conservation behavior to conserve the {Sumatran} orangutan},
	issn = {1523-1739},
	url = {http://dx.doi.org/10.1111/cobi.12650},
	doi = {10.1111/cobi.12650},
	journal = {Conservation Biology},
	author = {Nilsson, Danielle and Gramotnev, Galina and Baxter, Greg and Butler, James R. A. and Wich, Serge A. and McAlpine, Clive A.},
	year = {2016},
	pages = {n/a--n/a},
}

@incollection{wichWingsWildlifeUse2016,
	address = {Oxon, UK},
	title = {Wings for wildlife: the use of conservation drones, challenges and opportunities},
	isbn = {1-317-01753-6},
	booktitle = {The {Good} {Drone}},
	publisher = {Routledge},
	author = {Wich, Serge and Scott, Lorna and Koh, Lian Pin},
	editor = {Sandvik, Kristin. B. and Jumbert, Maria. G.},
	year = {2016},
	pages = {153--167},
}

@book{wichIntroductionPrimateConservation2016,
	address = {New York, USA},
	title = {An introduction to primate conservation},
	publisher = {Oxford University Press},
	author = {Wich, S. A. and Marshall, A. J.},
	year = {2016},
}

@article{wichLandcoverChangesPredict2016,
	title = {Land-cover changes predict steep declines for the {Sumatran} orangutan ({Pongo} abelii)},
	volume = {2},
	url = {http://advances.sciencemag.org/content/2/3/e1500789.abstract},
	doi = {10.1126/sciadv.1500789},
	abstract = {Positive news about Sumatran orangutans is rare. The species is critically endangered because of forest loss and poaching, and therefore, determining the impact of future land-use change on this species is important. To date, the total Sumatran orangutan population has been estimated at 6600 individuals. On the basis of new transect surveys, we estimate a population of 14,613 in 2015. This higher estimate is due to three factors. First, orangutans were found at higher elevations, elevations previously considered outside of their range and, consequently, not surveyed previously. Second, orangutans were found more widely distributed in logged forests. Third, orangutans were found in areas west of the Toba Lake that were not previously surveyed. This increase in numbers is therefore due to a more wide-ranging survey effort and is not indicative of an increase in the orangutan population in Sumatra. There are evidently more Sumatran orangutans remaining in the wild than we thought, but the species remains under serious threat. Current scenarios for future forest loss predict that as many as 4500 individuals could vanish by 2030. Despite the positive finding that the population is double the size previously estimated, our results indicate that future deforestation will continue to be the cause of rapid declines in orangutan numbers. Hence, we urge that all developmental planning involving forest loss be accompanied by appropriate environmental impact assessments conforming with the current national and provincial legislations, and, through these, implement specific measures to reduce or, better, avoid negative impacts on forests where orangutans occur.},
	number = {3},
	journal = {Science Advances},
	author = {Wich, Serge A. and Singleton, Ian and Nowak, Matthew G. and Utami Atmoko, Sri Suci and Nisam, Gonda and Arif, Sugesti Mhd and Putra, Rudi H. and Ardi, Rio and Fredriksson, Gabriella and Usher, Graham and Gaveau, David L. A. and Kühl, Hjalmar S.},
	year = {2016},
	pages = {e1500789.},
}

Positive news about Sumatran orangutans is rare. The species is critically endangered because of forest loss and poaching, and therefore, determining the impact of future land-use change on this species is important. To date, the total Sumatran orangutan population has been estimated at 6600 individuals. On the basis of new transect surveys, we estimate a population of 14,613 in 2015. This higher estimate is due to three factors. First, orangutans were found at higher elevations, elevations previously considered outside of their range and, consequently, not surveyed previously. Second, orangutans were found more widely distributed in logged forests. Third, orangutans were found in areas west of the Toba Lake that were not previously surveyed. This increase in numbers is therefore due to a more wide-ranging survey effort and is not indicative of an increase in the orangutan population in Sumatra. There are evidently more Sumatran orangutans remaining in the wild than we thought, but the species remains under serious threat. Current scenarios for future forest loss predict that as many as 4500 individuals could vanish by 2030. Despite the positive finding that the population is double the size previously estimated, our results indicate that future deforestation will continue to be the cause of rapid declines in orangutan numbers. Hence, we urge that all developmental planning involving forest loss be accompanied by appropriate environmental impact assessments conforming with the current national and provincial legislations, and, through these, implement specific measures to reduce or, better, avoid negative impacts on forests where orangutans occur.

@article{wijedasaDenialLongtermIssues2016,
	title = {Denial of long-term issues with agriculture on tropical peatlands will have devastating consequences},
	issn = {1365-2486},
	url = {http://dx.doi.org/10.1111/gcb.13516},
	doi = {10.1111/gcb.13516},
	journal = {Global Change Biology},
	author = {Wijedasa, Lahiru S. and Jauhiainen, Jyrki and Könönen, Mari and Lampela, Maija and Vasander, Harri and LeBlanc, Marie-Claire and Evers, Stephanie and Smith, Thomas E. L. and Yule, Catherine M. and Varkkey, Helena and Lupascu, Massimo and Parish, Faizal and Singleton, Ian and Clements, Gopalasamy R. and Aziz, Sheema Abdul and Harrison, Mark E. and Cheyne, Susan and Anshari, Gusti Z. and Meijaard, Erik and Goldstein, Jenny E. and Waldron, Susan and Hergoualc'h, Kristell and Dommain, René and Frolking, Steve and Evans, Christopher D. and Posa, Mary Rose C. and Glaser, Paul H. and Suryadiputra, Nyoman and Lubis, Reza and Santika, Truly and Padfield, Rory and Kurnianto, Sofyan and Hadisiswoyo, Panut and Lim, Teck Wyn and Page, Susan E. and Gauci, Vincent and van der Meer, Peter J. and Buckland, Helen and Garnier, Fabien and Samuel, Marshall K. and Choo, Liza Nuriati Lim Kim and O'Reilly, Patrick and Warren, Matthew and Suksuwan, Surin and Sumarga, Elham and Jain, Anuj and Laurance, William F. and Couwenberg, John and Joosten, Hans and Vernimmen, Ronald and Hooijer, Aljosja and Malins, Chris and Cochrane, Mark A. and Perumal, Balu and Siegert, Florian and Peh, Kelvin S. H. and Comeau, Louis-Pierre and Verchot, Louis and Harvey, Charles F. and Cobb, Alex and Jaafar, Zeehan and Wösten, Henk and Manuri, Solichin and Müller, Moritz and Giesen, Wim and Phelps, Jacob and Yong, Ding Li and Silvius, Marcel and Wedeux, Béatrice M. M. and Hoyt, Alison and Osaki, Mitsuru and Takashi, Hirano and Takahashi, Hidenori and Kohyama, Takashi S. and Haraguchi, Akira and Nugroho, Nunung P. and Coomes, David A. and Quoi, Le Phat and Dohong, Alue and Gunawan, Haris and Gaveau, David L. A. and Langner, Andreas and Lim, Felix K. S. and Edwards, David P. and Giam, Xingli and van der Werf, Guido and Carmenta, Rachel and Verwer, Caspar C. and Gibson, Luke and Grandois, Laure and Graham, Laura Linda Bozena and Regalino, Jhanson and Wich, Serge A. and Rieley, Jack and Kettridge, Nicholas and Brown, Chloe and Pirard, Romain and Moore, Sam and Ripoll Capilla, B. and Ballhorn, Uwe and Ho, Hua Chew and Hoscilo, Agata and Lohberger, Sandra and Evans, Theodore A. and Yulianti, Nina and Blackham, Grace and {Onrizal} and Husson, Simon and Murdiyarso, Daniel and Pangala, Sunita and Cole, Lydia E. S. and Tacconi, Luca and Segah, Hendrik and Tonoto, Prayoto and Lee, Janice S. H. and Schmilewski, Gerald and Wulffraat, Stephan and Putra, Erianto Indra and Cattau, Megan E. and Clymo, R. S. and Morrison, Ross and Mujahid, Aazani and Miettinen, Jukka and Liew, Soo Chin and Valpola, Samu and Wilson, David and D'Arcy, Laura and Gerding, Michiel and Sundari, Siti and Thornton, Sara A. and Kalisz, Barbara and Chapman, Stephen J. and Su, Ahmad Suhaizi Mat and Basuki, Imam and Itoh, Masayuki and Traeholt, Carl and Sloan, Sean and Sayok, Alexander K. and Andersen, Roxane},
	year = {2016},
	pages = {n/a--n/a},
}

@article{runtingAlternativeFuturesBorneo2015,
	title = {Alternative futures for {Borneo} show the value of integrating economic and conservation targets across borders},
	volume = {6},
	url = {http://dx.doi.org/10.1038/ncomms7819},
	doi = {10.1038/ncomms7819},
	abstract = {Balancing economic development with international commitments to protect biodiversity is a global challenge. Achieving this balance requires an understanding of the possible consequences of alternative future scenarios for a range of stakeholders. We employ an integrated economic and environmental planning approach to evaluate four alternative futures for the mega-diverse island of Borneo. We show what could be achieved if the three national jurisdictions of Borneo coordinate efforts to achieve their public policy targets and allow a partial reallocation of planned land uses. We reveal the potential for Borneo to simultaneously retain [sim]50\% of its land as forests, protect adequate habitat for the Bornean orangutan (Pongo pygmaeus) and Bornean elephant (Elephas maximus borneensis), and achieve an opportunity cost saving of over US[dollar]43 billion. Such coordination would depend on enhanced information sharing and reforms to land-use planning, which could be supported by the increasingly international nature of economies and conservation efforts.},
	journal = {Nat Commun},
	author = {Runting, Rebecca K. and Meijaard, Erik and Abram, Nicola K. and Wells, Jessie A. and Gaveau, David L. A. and Ancrenaz, Marc and Posssingham, Hugh P. and Wich, Serge A. and Ardiansyah, Fitrian and Gumal, Melvin T. and Ambu, Laurentius N. and Wilson, Kerrie A.},
	year = {2015},
}

Balancing economic development with international commitments to protect biodiversity is a global challenge. Achieving this balance requires an understanding of the possible consequences of alternative future scenarios for a range of stakeholders. We employ an integrated economic and environmental planning approach to evaluate four alternative futures for the mega-diverse island of Borneo. We show what could be achieved if the three national jurisdictions of Borneo coordinate efforts to achieve their public policy targets and allow a partial reallocation of planned land uses. We reveal the potential for Borneo to simultaneously retain [sim]50% of its land as forests, protect adequate habitat for the Bornean orangutan (Pongo pygmaeus) and Bornean elephant (Elephas maximus borneensis), and achieve an opportunity cost saving of over US[dollar]43 billion. Such coordination would depend on enhanced information sharing and reforms to land-use planning, which could be supported by the increasingly international nature of economies and conservation efforts.

@article{slikEstimateNumberTropical2015,
	title = {An estimate of the number of tropical tree species},
	volume = {112},
	url = {http://www.pnas.org/content/112/24/7472.abstract},
	doi = {10.1073/pnas.1423147112},
	abstract = {The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher’s alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼40,000 and ∼53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼19,000–25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼4,500–6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.},
	number = {24},
	journal = {Proceedings of the National Academy of Sciences},
	author = {Slik, J. W. Ferry and Arroyo-Rodríguez, Víctor and Aiba, Shin-Ichiro and Alvarez-Loayza, Patricia and Alves, Luciana F. and Ashton, Peter and Balvanera, Patricia and Bastian, Meredith L. and Bellingham, Peter J. and van den Berg, Eduardo and Bernacci, Luis and da Conceição Bispo, Polyanna and Blanc, Lilian and Böhning-Gaese, Katrin and Boeckx, Pascal and Bongers, Frans and Boyle, Brad and Bradford, Matt and Brearley, Francis Q. and Breuer-Ndoundou Hockemba, Mireille and Bunyavejchewin, Sarayudh and Calderado Leal Matos, Darley and Castillo-Santiago, Miguel and Catharino, Eduardo L. M. and Chai, Shauna-Lee and Chen, Yukai and Colwell, Robert K. and Chazdon, Robin L. and Clark, Connie and Clark, David B. and Clark, Deborah A. and Culmsee, Heike and Damas, Kipiro and Dattaraja, Handanakere S. and Dauby, Gilles and Davidar, Priya and DeWalt, Saara J. and Doucet, Jean-Louis and Duque, Alvaro and Durigan, Giselda and Eichhorn, Karl A. O. and Eisenlohr, Pedro V. and Eler, Eduardo and Ewango, Corneille and Farwig, Nina and Feeley, Kenneth J. and Ferreira, Leandro and Field, Richard and de Oliveira Filho, Ary T. and Fletcher, Christine and Forshed, Olle and Franco, Geraldo and Fredriksson, Gabriella and Gillespie, Thomas and Gillet, Jean-François and Amarnath, Giriraj and Griffith, Daniel M. and Grogan, James and Gunatilleke, Nimal and Harris, David and Harrison, Rhett and Hector, Andy and Homeier, Jürgen and Imai, Nobuo and Itoh, Akira and Jansen, Patrick A. and Joly, Carlos A. and de Jong, Bernardus H. J. and Kartawinata, Kuswata and Kearsley, Elizabeth and Kelly, Daniel L. and Kenfack, David and Kessler, Michael and Kitayama, Kanehiro and Kooyman, Robert and Larney, Eileen and Laumonier, Yves and Laurance, Susan and Laurance, William F. and Lawes, Michael J. and Amaral, Ieda Leao do and Letcher, Susan G. and Lindsell, Jeremy and Lu, Xinghui and Mansor, Asyraf and Marjokorpi, Antti and Martin, Emanuel H. and Meilby, Henrik and Melo, Felipe P. L. and Metcalfe, Daniel J. and Medjibe, Vincent P. and Metzger, Jean Paul and Millet, Jerome and Mohandass, D. and Montero, Juan C. and de Morisson Valeriano, Márcio and Mugerwa, Badru and Nagamasu, Hidetoshi and Nilus, Reuben and Ochoa-Gaona, Susana and {Onrizal} and Page, Navendu and Parolin, Pia and Parren, Marc and Parthasarathy, Narayanaswamy and Paudel, Ekananda and Permana, Andrea and Piedade, Maria T. F. and Pitman, Nigel C. A. and Poorter, Lourens and Poulsen, Axel D. and Poulsen, John and Powers, Jennifer and Prasad, Rama C. and Puyravaud, Jean-Philippe and Razafimahaimodison, Jean-Claude and Reitsma, Jan and dos Santos, João Roberto and Roberto Spironello, Wilson and Romero-Saltos, Hugo and Rovero, Francesco and Rozak, Andes Hamuraby and Ruokolainen, Kalle and Rutishauser, Ervan and Saiter, Felipe and Saner, Philippe and Santos, Braulio A. and Santos, Fernanda and Sarker, Swapan K. and Satdichanh, Manichanh and Schmitt, Christine B. and Schöngart, Jochen and Schulze, Mark and Suganuma, Marcio S. and Sheil, Douglas and da Silva Pinheiro, Eduardo and Sist, Plinio and Stevart, Tariq and Sukumar, Raman and Sun, I.-Fang and Sunderland, Terry and Suresh, H. S. and Suzuki, Eizi and Tabarelli, Marcelo and Tang, Jangwei and Targhetta, Natália and Theilade, Ida and Thomas, Duncan W. and Tchouto, Peguy and Hurtado, Johanna and Valencia, Renato and van Valkenburg, Johan L. C. H. and Van Do, Tran and Vasquez, Rodolfo and Verbeeck, Hans and Adekunle, Victor and Vieira, Simone A. and Webb, Campbell O. and Whitfeld, Timothy and Wich, Serge A. and Williams, John and Wittmann, Florian and Wöll, Hannsjoerg and Yang, Xiaobo and Adou Yao, C. Yves and Yap, Sandra L. and Yoneda, Tsuyoshi and Zahawi, Rakan A. and Zakaria, Rahmad and Zang, Runguo and de Assis, Rafael L. and Garcia Luize, Bruno and Venticinque, Eduardo M.},
	month = jun,
	year = {2015},
	pages = {7472--7477},
}

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher’s alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼40,000 and ∼53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼19,000–25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼4,500–6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.

@article{struebigAnticipatedClimateLandcover2015,
	title = {Anticipated climate and land‐cover changes reveal refuge areas for {Borneo}'s orang‐utans},
	issn = {1365-2486},
	journal = {Global change biology},
	author = {Struebig, Matthew J and Fischer, Manuela and Gaveau, David LA and Meijaard, Erik and Wich, Serge A and Gonner, Catherine and Sykes, Rachel and Wilting, Andreas and Kramer‐Schadt, Stephanie},
	year = {2015},
}

@article{vanandelLocatingChimpanzeeNests2015,
	title = {Locating chimpanzee nests and identifying fruiting trees with an {Unmanned} {Aerial} {Vehicle}},
	volume = {77},
	number = {1122-1134},
	journal = {Americal Journal of Primatology},
	author = {van Andel, A. and Wich, S.A. and Boesch, C and Koh, Lian Pin and Robbins, M.M. and Kelly, J. and Kühl, H.S.},
	year = {2015},
}

@incollection{wichDronesConservation2015,
	title = {Drones and conservation},
	booktitle = {Drones and aerial observation: {New} technologies for property rights, human rights, and global development. {A} primer.},
	publisher = {New America},
	author = {Wich, S. A.},
	editor = {Kakaes, K.},
	year = {2015},
	pages = {63--71},
}

@article{ancrenazComingTreesTerrestrial2014,
	title = {Coming down from the trees: {Is} terrestrial activity in {Bornean} orangutans natural or disturbance driven?},
	volume = {4},
	url = {http://dx.doi.org/10.1038/srep04024},
	doi = {10.1038/srep04024},
	journal = {Scientific Reports},
	author = {Ancrenaz, Marc and Sollmann, Rahel and Meijaard, Erik and Hearn, Andrew J. and Ross, Joanna and Samejima, Hiromitsu and Loken, Brent and Cheyne, Susan M. and Stark, Danica J. and Gardner, Penny C. and Goossens, Benoit and Mohamed, Azlan and Bohm, Torsten and Matsuda, Ikki and Nakabayasi, Miyabi and Lee, Shan Khee and Bernard, Henry and Brodie, Jedediah and Wich, Serge and Fredriksson, Gabriella and Hanya, Goro and Harrison, Mark E. and Kanamori, Tomoko and Kretzschmar, Petra and Macdonald, David W. and Riger, Peter and Spehar, Stephanie and Ambu, Laurentius N. and Wilting, Andreas},
	year = {2014},
	pages = {4024},
}

@inproceedings{chenActiveDetectionAdaptive2014,
	title = {Active detection via adaptive submodularity},
	author = {Chen, Yuxin and Shioi, Hiroaki and Montesinos, Cesar Fuentes and Koh, Lian Pin and Wich, Serge and Krause, Andreas},
	year = {2014},
	pages = {55--63},
}

@article{paneque-galvezSmallDronesCommunitybased2014,
	title = {Small drones for community-based forest monitoring: {An} assessment of their feasibility and potential in tropical areas},
	volume = {5},
	number = {6},
	journal = {Forests},
	author = {Paneque-Gálvez, Jaime and McCall, Michael K and Napoletano, Brian M and Wich, Serge A and Koh, Lian Pin},
	year = {2014},
	pages = {1481--1507},
}

@article{vangemertNatureConservationDrones2014,
	title = {Nature {Conservation} {Drones} for {Automatic} {Localization} and {Counting} of {Animals}},
	author = {van Gemert, Jan C and Verschoor, Camiel R and Mettes, Pascal and Epema, Kitso and Koh, Lian Pin and Wich, Serge},
	year = {2014},
}

@article{wichWillOilPalms2014,
	title = {Will {Oil} {Palm}’s {Homecoming} {Spell} {Doom} for {Africa}’s {Great} {Apes}?},
	volume = {24},
	url = {http://www.cell.com/current-biology/abstract/S0960-9822(14)00680-0},
	doi = {10.1016/j.cub.2014.05.077},
	number = {14},
	urldate = {2014-08-27},
	journal = {Current Biology},
	author = {Wich, Serge A and Garcia-Ulloa, John and Kühl, Hjalmar S and Humle, Tatanya and Lee, Janice S H. and Koh, Lian Pin},
	year = {2014},
	pages = {1659--1663},
}

@incollection{wichPreliminaryDataHighland2014,
	series = {Developments in {Primatology}: {Progress} and {Prospects}},
	title = {Preliminary {Data} on the {Highland} {Sumatran} {Orangutans} ({Pongo} abelii) of {Batang} {Toru}},
	isbn = {978-1-4614-8174-4},
	url = {http://dx.doi.org/10.1007/978-1-4614-8175-1_15},
	doi = {10.1007/978-1-4614-8175-1_15},
	language = {English},
	booktitle = {High {Altitude} {Primates}},
	publisher = {Springer New York},
	author = {Wich, S. A. and Usher, G. and Peters, H. H. and Khakim, MokhamadFaesalRakhman and Nowak, M. G. and Fredriksson, G. M.},
	editor = {Grow, Nanda B. and Gursky-Doyen, Sharon and Krzton, Alicia},
	year = {2014},
	note = {Section: 15},
	pages = {265--283},
}

@article{gaveauReconcilingForestConservation2013,
	title = {Reconciling {Forest} {Conservation} and {Logging} in {Indonesian} {Borneo}},
	volume = {8},
	issn = {1932-6203},
	number = {8},
	journal = {PloS one},
	author = {Gaveau, David LA and Kshatriya, Mrigesh and Sheil, Douglas and Sloan, Sean and Molidena, Elis and Wijaya, Arief and Wich, Serge and Ancrenaz, Marc and Hansen, Matthew and Broich, Mark},
	year = {2013},
	pages = {e69887},
}

@incollection{marshallCharacterizationPrimateEnvironments2013,
	title = {Characterization of primate environments through assessment of plant phenology},
	booktitle = {Primate ecology and conservation: {A} handbook of techniques},
	publisher = {Oxford University Press},
	author = {Marshall, Andrew J and Wich, SA},
	editor = {Sterling, E. J. and Bynum, N. and Blair, Mary E.},
	year = {2013},
	pages = {103--127},
}

@article{naterMarkedPopulationStructure2013,
	title = {Marked {Population} {Structure} and {Recent} {Migration} in the {Critically} {Endangered} {Sumatran} {Orangutan} ({Pongo} abelii)},
	volume = {104},
	url = {http://jhered.oxfordjournals.org/content/104/1/2.abstract},
	doi = {10.1093/jhered/ess065},
	abstract = {A multitude of factors influence how natural populations are genetically structured, including dispersal barriers, inhomogeneous habitats, and social organization. Such population subdivision is of special concern in endangered species, as it may lead to reduced adaptive potential and inbreeding in local subpopulations, thus increasing the risk of future extinctions. With only 6600 animals left in the wild, Sumatran orangutans (Pongo abelii) are among the most endangered, but also most enigmatic, great ape species. In order to infer the fine-scale population structure and connectivity of Sumatran orangutans, we analyzed the most comprehensive set of samples to date, including mitochondrial hyper-variable region I haplotypes for 123 individuals and genotypes of 27 autosomal microsatellite markers for 109 individuals. For both mitochondrial and autosomal markers, we found a pronounced population structure, caused by major rivers, mountain ridges, and the Toba caldera. We found that genetic diversity and corresponding long-term effective population size estimates vary strongly among sampling regions for mitochondrial DNA, but show remarkable similarity for autosomal markers, hinting at male-driven long-distance gene flow. In support of this, we identified several individuals that were most likely sired by males originating from other genetic clusters. Our results highlight the effect of natural barriers in shaping the genetic structure of great ape populations, but also point toward important dispersal corridors on northern Sumatra that allow for genetic exchange.},
	number = {1},
	journal = {Journal of Heredity},
	author = {Nater, Alexander and Arora, Natasha and Greminger, Maja P. and van Schaik, Carel P. and Singleton, Ian and Wich, Serge A. and Fredriksson, Gabriella and Perwitasari-Farajallah, Dyah and Pamungkas, Joko and Krützen, Michael},
	month = jan,
	year = {2013},
	pages = {2--13},
}

A multitude of factors influence how natural populations are genetically structured, including dispersal barriers, inhomogeneous habitats, and social organization. Such population subdivision is of special concern in endangered species, as it may lead to reduced adaptive potential and inbreeding in local subpopulations, thus increasing the risk of future extinctions. With only 6600 animals left in the wild, Sumatran orangutans (Pongo abelii) are among the most endangered, but also most enigmatic, great ape species. In order to infer the fine-scale population structure and connectivity of Sumatran orangutans, we analyzed the most comprehensive set of samples to date, including mitochondrial hyper-variable region I haplotypes for 123 individuals and genotypes of 27 autosomal microsatellite markers for 109 individuals. For both mitochondrial and autosomal markers, we found a pronounced population structure, caused by major rivers, mountain ridges, and the Toba caldera. We found that genetic diversity and corresponding long-term effective population size estimates vary strongly among sampling regions for mitochondrial DNA, but show remarkable similarity for autosomal markers, hinting at male-driven long-distance gene flow. In support of this, we identified several individuals that were most likely sired by males originating from other genetic clusters. Our results highlight the effect of natural barriers in shaping the genetic structure of great ape populations, but also point toward important dispersal corridors on northern Sumatra that allow for genetic exchange.

@article{slikLargeTreesDrive2013,
	title = {Large trees drive forest aboveground biomass variation in moist lowland forests across the tropics},
	volume = {22},
	issn = {1466-8238},
	url = {http://dx.doi.org/10.1111/geb.12092},
	doi = {10.1111/geb.12092},
	number = {12},
	journal = {Global Ecology and Biogeography},
	author = {Slik, J. W. Ferry and Paoli, Gary and McGuire, Krista and Amaral, Ieda and Barroso, Jorcely and Bastian, Meredith and Blanc, Lilian and Bongers, Frans and Boundja, Patrick and Clark, Connie and Collins, Murray and Dauby, Gilles and Ding, Yi and Doucet, Jean-Louis and Eler, Eduardo and Ferreira, Leandro and Forshed, Olle and Fredriksson, Gabriella and Gillet, Jean-Francois and Harris, David and Leal, Miguel and Laumonier, Yves and Malhi, Yadvinder and Mansor, Asyraf and Martin, Emanuel and Miyamoto, Kazuki and Araujo-Murakami, Alejandro and Nagamasu, Hidetoshi and Nilus, Reuben and Nurtjahya, Eddy and Oliveira, Átila and Onrizal, Onrizal and Parada-Gutierrez, Alexander and Permana, Andrea and Poorter, Lourens and Poulsen, John and Ramirez-Angulo, Hirma and Reitsma, Jan and Rovero, Francesco and Rozak, Andes and Sheil, Douglas and Silva-Espejo, Javier and Silveira, Marcos and Spironelo, Wilson and ter Steege, Hans and Stevart, Tariq and Navarro-Aguilar, Gilberto Enrique and Sunderland, Terry and Suzuki, Eizi and Tang, Jianwei and Theilade, Ida and van der Heijden, Geertje and van Valkenburg, Johan and Van Do, Tran and Vilanova, Emilio and Vos, Vincent and Wich, Serge and Wöll, Hannsjoerg and Yoneda, Tsuyoshi and Zang, Runguo and Zhang, Ming-Gang and Zweifel, Nicole},
	year = {2013},
	pages = {1261--1271},
}

@article{hardusEffectsLoggingOrangutan2012,
	title = {Effects of logging on orangutan behavior},
	volume = {146},
	issn = {0006-3207},
	number = {1},
	journal = {Biological Conservation},
	author = {Hardus, Madeleine E and Lameira, Adriano R and Menken, Steph BJ and Wich, Serge A},
	year = {2012},
	pages = {177--187},
}

@article{hardusBehavioralEcologicalEvolutionary2012,
	title = {Behavioral, ecological, and evolutionary aspects of meat-eating by {Sumatran} orangutans ({Pongo} abelii)},
	volume = {33},
	issn = {0164-0291},
	number = {2},
	journal = {International journal of primatology},
	author = {Hardus, Madeleine E and Lameira, Adriano R and Zulfa, Astri and Atmoko, S Suci Utami and de Vries, Han and Wich, Serge A},
	year = {2012},
	pages = {287--304},
}

@article{kohDawnDroneEcology2012,
	title = {Dawn of drone ecology: low-cost autonomous aerial vehicles for conservation},
	volume = {5},
	issn = {1940-0829},
	number = {2},
	journal = {Tropical Conservation Science},
	author = {Koh, Lian Pin and Wich, Serge A},
	year = {2012},
	pages = {121--132},
}

@article{wichHuntingSumatranOrangutans2012,
	title = {Hunting of {Sumatran} orang-utans and its importance in determining distribution and density},
	volume = {146},
	issn = {0006-3207},
	number = {1},
	journal = {Biological Conservation},
	author = {Wich, SA and Fredriksson, GM and Usher, G and Peters, HH and Priatna, D and Basalamah, F and Susanto, W and Kühl, H},
	year = {2012},
	pages = {163--169},
}

@article{wichUnderstandingImpactsLandUse2012,
	title = {Understanding the {Impacts} of {Land}-{Use} {Policies} on a {Threatened} {Species}: {Is} {There} a {Future} for the {Bornean} {Orang}-utan?},
	volume = {7},
	url = {http://dx.doi.org/10.1371%2Fjournal.pone.0049142},
	doi = {10.1371/journal.pone.0049142},
	number = {11},
	journal = {PLoS ONE},
	author = {Wich, Serge A. and Gaveau, David and Abram, Nicola and Ancrenaz, Marc and Baccini, Alessandro and Brend, Stephen and Curran, Lisa and Delgado, Roberto A. and Erman, Andi and Fredriksson, Gabriella M. and Goossens, Benoit and Husson, Simon J. and Lackman, Isabelle and Marshall, Andrew J. and Naomi, Anita and Molidena, Elis and {Nardiyono} and Nurcahyo, Anton and Odom, Kisar and Panda, Adventus and {Purnomo} and Rafiastanto, Andjar and Ratnasari, Dessy and Santana, Adi H. and Sapari, Imam and van Schaik, Carel P. and Sihite, Jamartin and Spehar, Stephanie and Santoso, Eddy and Suyoko, Amat and Tiju, Albertus and Usher, Graham and Atmoko, Sri Suci Utami and Willems, Erik P. and Meijaard, Erik},
	year = {2012},
	pages = {e49142},
}

@article{wichCallCulturesOrangutans2012,
	title = {Call cultures in orang-utans},
	volume = {7},
	issn = {1932-6203},
	number = {5},
	journal = {PloS one},
	author = {Wich, Serge A and Krützen, Michael and Lameira, Adriano R and Nater, Alexander and Arora, Natasha and Bastian, Meredith L and Meulman, Ellen and Morrogh-Bernard, Helen C and Atmoko, S Suci Utami and Pamungkas, Joko},
	year = {2012},
	pages = {e36180},
}

@article{meijaardWhyDontWe2011,
	title = {Why don't we ask? {A} complementary method for assessing the status of great apes},
	volume = {6},
	issn = {1932-6203},
	number = {3},
	journal = {PloS one},
	author = {Meijaard, Erik and Mengersen, Kerrie and Buchori, Damayanti and Nurcahyo, Anton and Ancrenaz, Marc and Wich, Serge and Atmoko, Sri Suci Utami and Tjiu, Albertus and Prasetyo, Didik and Hadiprakarsa, Yokyok},
	year = {2011},
	pages = {e18008},
}

@article{naterSexBiasedDispersalVolcanic2011,
	title = {Sex-{Biased} {Dispersal} and {Volcanic} {Activities} {Shaped} {Phylogeographic} {Patterns} of {Extant} {Orangutans} (genus: {Pongo})},
	volume = {28},
	url = {http://mbe.oxfordjournals.org/content/28/8/2275.abstract},
	doi = {10.1093/molbev/msr042},
	abstract = {The Southeast Asian Sunda archipelago harbors a rich biodiversity with a substantial proportion of endemic species. The evolutionary history of these species has been drastically influenced by environmental forces, such as fluctuating sea levels, climatic changes, and severe volcanic activities. Orangutans (genus: Pongo), the only Asian great apes, are well suited to study the relative impact of these forces due to their well-documented behavioral ecology, strict habitat requirements, and exceptionally slow life history. We investigated the phylogeographic patterns and evolutionary history of orangutans in the light of the complex geological and climatic history of the Sunda archipelago. Our study is based on the most extensive genetic sampling to date, covering the entire range of extant orangutan populations. Using data from three mitochondrial DNA (mtDNA) genes from 112 wild orangutans, we show that Sumatran orangutans, Pongo abelii, are paraphyletic with respect to Bornean orangutans (P. pygmaeus), the only other currently recognized species within this genus. The deepest split in the mtDNA phylogeny of orangutans occurs across the Toba caldera in northern Sumatra and, not as expected, between both islands. Until the recent past, the Toba region has experienced extensive volcanic activity, which has shaped the current phylogeographic patterns. Like their Bornean counterparts, Sumatran orangutans exhibit a strong, yet previously undocumented structuring into four geographical clusters. However, with 3.50 Ma, the Sumatran haplotypes have a much older coalescence than their Bornean counterparts (178 kya). In sharp contrast to the mtDNA data, 18 Y-chromosomal polymorphisms show a much more recent coalescence within Sumatra compared with Borneo. Moreover, the deep geographic structure evident in mtDNA is not reflected in the male population history, strongly suggesting male-biased dispersal. We conclude that volcanic activities have played an important role in the evolutionary history of orangutans and potentially of many other forest-dwelling Sundaland species. Furthermore, we demonstrate that a strong sex bias in dispersal can lead to conflicting patterns in uniparentally inherited markers even at a genus-wide scale, highlighting the need for a combined usage of maternally and paternally inherited marker systems in phylogenetic studies.},
	number = {8},
	journal = {Molecular Biology and Evolution},
	author = {Nater, Alexander and Nietlisbach, Pirmin and Arora, Natasha and van Schaik, Carel P. and van Noordwijk, Maria A. and Willems, Erik P. and Singleton, Ian and Wich, Serge A. and Goossens, Benoit and Warren, Kristin S. and Verschoor, Ernst J. and Perwitasari-Farajallah, Dyah and Pamungkas, Joko and Krützen, Michael},
	month = aug,
	year = {2011},
	pages = {2275--2288},
}

The Southeast Asian Sunda archipelago harbors a rich biodiversity with a substantial proportion of endemic species. The evolutionary history of these species has been drastically influenced by environmental forces, such as fluctuating sea levels, climatic changes, and severe volcanic activities. Orangutans (genus: Pongo), the only Asian great apes, are well suited to study the relative impact of these forces due to their well-documented behavioral ecology, strict habitat requirements, and exceptionally slow life history. We investigated the phylogeographic patterns and evolutionary history of orangutans in the light of the complex geological and climatic history of the Sunda archipelago. Our study is based on the most extensive genetic sampling to date, covering the entire range of extant orangutan populations. Using data from three mitochondrial DNA (mtDNA) genes from 112 wild orangutans, we show that Sumatran orangutans, Pongo abelii, are paraphyletic with respect to Bornean orangutans (P. pygmaeus), the only other currently recognized species within this genus. The deepest split in the mtDNA phylogeny of orangutans occurs across the Toba caldera in northern Sumatra and, not as expected, between both islands. Until the recent past, the Toba region has experienced extensive volcanic activity, which has shaped the current phylogeographic patterns. Like their Bornean counterparts, Sumatran orangutans exhibit a strong, yet previously undocumented structuring into four geographical clusters. However, with 3.50 Ma, the Sumatran haplotypes have a much older coalescence than their Bornean counterparts (178 kya). In sharp contrast to the mtDNA data, 18 Y-chromosomal polymorphisms show a much more recent coalescence within Sumatra compared with Borneo. Moreover, the deep geographic structure evident in mtDNA is not reflected in the male population history, strongly suggesting male-biased dispersal. We conclude that volcanic activities have played an important role in the evolutionary history of orangutans and potentially of many other forest-dwelling Sundaland species. Furthermore, we demonstrate that a strong sex bias in dispersal can lead to conflicting patterns in uniparentally inherited markers even at a genus-wide scale, highlighting the need for a combined usage of maternally and paternally inherited marker systems in phylogenetic studies.

@article{wichWhichFactorsDetermine2011,
	title = {Which factors determine orangutan nests' detection probability along transects?},
	volume = {4},
	issn = {1940-0829},
	number = {1},
	journal = {Tropical Conservation Science},
	author = {Wich, Serge A and Boyko, Ryan H},
	year = {2011},
	pages = {53--63},
}

@book{wichOrangutansEconomicsSustainable2011,
	title = {Orangutans and the economics of sustainable forest management in {Sumatra}},
	isbn = {82-7701-095-8},
	publisher = {United Nations Environment Programme},
	author = {Wich, Serge A and Riswan, J and Refisch, J and Nellemann, C},
	year = {2011},
}

@article{jaeggiSocialLearningDiet2010,
	title = {Social learning of diet and foraging skills by wild immature {Bornean} orangutans: implications for culture},
	volume = {72},
	number = {1},
	journal = {American Journal of Primatology},
	author = {Jaeggi, A. V. and Dunkel, L. P. and van Noordwijk, M.A. and Wich, S. A. and Sura, A. A. L. and van Schaik, C.P.},
	year = {2010},
	pages = {62--71},
}

@article{meijaardDecliningOrangutanEncounter2010,
	title = {Declining orangutan encounter rates from {Wallace} to the present suggest the species was once more abundant},
	volume = {5},
	issn = {1932-6203},
	number = {8},
	journal = {PLoS One},
	author = {Meijaard, Erik and Welsh, Alan and Ancrenaz, Marc and Wich, Serge and Nijman, Vincent and Marshall, Andrew J},
	year = {2010},
	pages = {e12042},
}

@article{speharEstimatingOrangutanDensities2010,
	title = {Estimating orangutan densities using the standing crop and marked nest count methods: {Lessons} learned for conservation},
	volume = {42},
	issn = {0006-3606},
	number = {6},
	journal = {Biotropica},
	author = {Spehar, Stephanie N and Mathewson, Paul D and {Nuzuar} and Wich, Serge A and Marshall, Andrew J and Kuehl, Hjalmar and {Nardiyono} and Meijaard, Erik},
	year = {2010},
	pages = {748--757},
}

@article{leeDetectingIndustrialOil10,
	title = {Detecting industrial oil palm plantations on {Landsat} images with {Google} {Earth} {Engine}},
	volume = {4},
	issn = {2352-9385},
	url = {http://www.sciencedirect.com/science/article/pii/S235293851630129X},
	doi = {10.1016/j.rsase.2016.11.003},
	abstract = {Oil palm plantations are rapidly expanding in the tropics, which leads to deforestation and other associated damages to biodiversity and ecosystem services. Forest researchers and practitioners in developing nations are in need of a low-cost, accessible and user-friendly tool for detecting the establishment of industrial oil palm plantations. Google Earth Engine (GEE) is a cloud computing platform which hosts publicly available satellite images and allows for land cover classification using inbuilt algorithms. These algorithms conduct pixel-based classification via supervised learning. We demonstrate the use of GEE for the detection of industrial oil palm plantations in Tripa, Aceh, Indonesia. We performed land cover classification using different spectral bands (RGB, NIR, SWIR, TIR, all bands) from our Landsat 8 image to distinguish the following land cover classes: immature oil palm, mature oil palm, non-forest non-oil palm, forest, water, and clouds. The overall accuracy and Kappa coefficient were the highest using all bands for land cover classification, followed by RGB, SWIR, TIR, and NIR. Classification and Regression Trees (CART) and Random Forests (RFT) algorithms produced classified land cover maps which had higher overall accuracies and Kappa coefficients than the Minimum Distance (MD) algorithm. Object-based classification and using a combination of radar- and optic-based imagery are some ways in which oil palm detection can be improved within GEE. Despite its limitations, GEE does have the potential to be developed further into an accessible and low-cost tool for independent bodies to detect and monitor the expansion of oil palm plantations in the tropics.},
	journal = {Remote Sensing Applications: Society and Environment},
	author = {Lee, Janice Ser Huay and Wich, Serge and Widayati, Atiek and Koh, Lian Pin},
	year = {2010},
	pages = {219--224},
}

Oil palm plantations are rapidly expanding in the tropics, which leads to deforestation and other associated damages to biodiversity and ecosystem services. Forest researchers and practitioners in developing nations are in need of a low-cost, accessible and user-friendly tool for detecting the establishment of industrial oil palm plantations. Google Earth Engine (GEE) is a cloud computing platform which hosts publicly available satellite images and allows for land cover classification using inbuilt algorithms. These algorithms conduct pixel-based classification via supervised learning. We demonstrate the use of GEE for the detection of industrial oil palm plantations in Tripa, Aceh, Indonesia. We performed land cover classification using different spectral bands (RGB, NIR, SWIR, TIR, all bands) from our Landsat 8 image to distinguish the following land cover classes: immature oil palm, mature oil palm, non-forest non-oil palm, forest, water, and clouds. The overall accuracy and Kappa coefficient were the highest using all bands for land cover classification, followed by RGB, SWIR, TIR, and NIR. Classification and Regression Trees (CART) and Random Forests (RFT) algorithms produced classified land cover maps which had higher overall accuracies and Kappa coefficients than the Minimum Distance (MD) algorithm. Object-based classification and using a combination of radar- and optic-based imagery are some ways in which oil palm detection can be improved within GEE. Despite its limitations, GEE does have the potential to be developed further into an accessible and low-cost tool for independent bodies to detect and monitor the expansion of oil palm plantations in the tropics.

@article{alexanderLocatingEmergentTrees10,
	title = {Locating emergent trees in a tropical rainforest using data from an {Unmanned} {Aerial} {Vehicle} ({UAV})},
	volume = {72},
	issn = {0303-2434},
	url = {https://www.sciencedirect.com/science/article/pii/S0303243418303660},
	doi = {10.1016/j.jag.2018.05.024},
	journal = {International Journal of Applied Earth Observation and Geoinformation},
	author = {Alexander, Cici and Korstjens, Amanda H. and Hankinson, Emma and Usher, Graham and Harrison, Nathan and Nowak, Matthew G. and Abdullah, Abdullah and Wich, Serge A. and Hill, Ross A.},
	year = {2010},
	pages = {86--90},
}

@article{stankowichUngulateFlightResponses09,
	title = {Ungulate flight responses to human disturbance: {A} review and meta-analysis},
	volume = {141},
	issn = {0006-3207},
	url = {http://www.sciencedirect.com/science/article/pii/S0006320708002334},
	doi = {10.1016/j.biocon.2008.06.026},
	abstract = {As human recreation in natural areas increases, so does the potential for disturbance to wildlife, and many factors (environmental, disturbance type, experience with humans) influence the impact of disturbance. However, there exists no comprehensive examination of the effects of human disturbance on ungulate escape responses. I conducted a comprehensive review of studies measuring Artiodactyl escape responses (e.g., flight initiation distance, distance moved) to experimental harassment by humans and vehicles, and meta-analyses aimed at predictive questions about the impact of human disturbance on ungulate behavior under an optimization framework. I found evidence across studies that ungulates pay attention to approacher behavior, have greater perceptions of risk when disturbed in open habitats, and females or groups with young offspring show greater flight responses than adult groups. Increased group size and the presence of hunting showed weak but positive heterogeneous effects on flight behavior both between and within species. Humans on foot were more evocative than other stimuli (vehicles, noises). Populations in areas with higher levels of human traffic showed reduced wariness but a lack of alternative sites to move to may explain some of this effect. Hunted populations showed significantly greater flight responses than non-hunted populations. Finally, I suggest five factors to consider when forming predictive models of ungulate flight behavior: (1) how seasonal variation in reproductive status and body condition effects wariness, (2) the relative impacts of lethal and non-lethal human contact, and (3) unique natural history traits that may cause differences in flight behavior between populations, (4) the availability of alternative sites, and (5) shorter distances between feeding sites and refugia can reduce the impact of other factors on flight responses.},
	number = {9},
	journal = {Biological Conservation},
	author = {Stankowich, Theodore},
	year = {2009},
	pages = {2159--2173},
}

As human recreation in natural areas increases, so does the potential for disturbance to wildlife, and many factors (environmental, disturbance type, experience with humans) influence the impact of disturbance. However, there exists no comprehensive examination of the effects of human disturbance on ungulate escape responses. I conducted a comprehensive review of studies measuring Artiodactyl escape responses (e.g., flight initiation distance, distance moved) to experimental harassment by humans and vehicles, and meta-analyses aimed at predictive questions about the impact of human disturbance on ungulate behavior under an optimization framework. I found evidence across studies that ungulates pay attention to approacher behavior, have greater perceptions of risk when disturbed in open habitats, and females or groups with young offspring show greater flight responses than adult groups. Increased group size and the presence of hunting showed weak but positive heterogeneous effects on flight behavior both between and within species. Humans on foot were more evocative than other stimuli (vehicles, noises). Populations in areas with higher levels of human traffic showed reduced wariness but a lack of alternative sites to move to may explain some of this effect. Hunted populations showed significantly greater flight responses than non-hunted populations. Finally, I suggest five factors to consider when forming predictive models of ungulate flight behavior: (1) how seasonal variation in reproductive status and body condition effects wariness, (2) the relative impacts of lethal and non-lethal human contact, and (3) unique natural history traits that may cause differences in flight behavior between populations, (4) the availability of alternative sites, and (5) shorter distances between feeding sites and refugia can reduce the impact of other factors on flight responses.

@incollection{delgadoGeographicalVariationOrangutan2009,
	address = {New York},
	title = {Geographical variation in orangutan long calls},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {{ORANGUTANS}: {GEOGRAPHIC} {VARIATION} {IN} {BEHAVIORAL} {ECOLOGY} {AND} {CONSERVATION}},
	publisher = {Oxford Univ Press},
	author = {Delgado, R. A. and Lameira, A. R. and Davila Ross, M. and Husson, S. J. and Morrogh-Bernard, H. C. and Wich, S. A.},
	year = {2009},
	pages = {215--224},
}

@article{gaveauFutureForestsOrangutans2009,
	title = {The future of forests and orangutans ({Pongo} abelii) in {Sumatra}: predicting impacts of oil palm plantations, road construction, and mechanisms for reducing carbon emissions from deforestation},
	volume = {4},
	number = {3},
	journal = {Environmental Research Letters},
	author = {Gaveau, D. L. A. and Wich, S. and Epting, J. and Juhn, D. and Kanninen, M. and Leader-Williams, N.},
	month = jul,
	year = {2009},
	pages = {34013},
}

@incollection{hardusDescriptionOrangutansVocal2009,
	address = {New York},
	title = {A description of the orangutan's vocal and sound repertoire, with a focus on geographic variation},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {{ORANGUTANS}: {GEOGRAPHIC} {VARIATION} {IN} {BEHAVIORAL} {ECOLOGY} {AND} {CONSERVATION}},
	publisher = {Oxford Univ Press},
	author = {Hardus, M. E. and Lameira, A. R. and Singleton, I. and Morrogh-Bernard, H. C. and Knott, C. D. and Ancrenaz, M. and Utami Atmoko, S. S. and Wich, S. A.},
	year = {2009},
	pages = {49--64},
}

@article{hardusToolUseWild2009,
	title = {Tool use in wild orang-utans modifies sound production: a functionally deceptive innovation?},
	volume = {(Advance online publication)},
	issn = {0962-8452},
	journal = {PROCEEDINGS. BIOLOGICAL SCIENCES/THE ROYAL SOCIETY},
	author = {Hardus, M. E. and Lameira, A. R. and Van Schaik, C. P. and Wich, S. A.},
	year = {2009},
	pages = {online(1--6)},
}

@incollection{hussonOrangutanDistributionDensity2009,
	address = {New York},
	title = {Orangutan distribution, density, abundance and impacts of disturbance},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {Orangutans: {Geographic} variation in behavioral ecology and conservation},
	publisher = {Oxford Univ Press},
	author = {Husson, S. J. and Wich, S. A. and Marshall, A. J. and Dennis, R. D. and Ancrenaz, M. and Brassey, R. and Gumal, M. and Hearn, A. J. and Meijaard, E. and Simorangkir, T. and Singleton, I.},
	editor = {Wich, S. A. and Utami Atmoko, S. S. and Mitra Setia, T. and Schaik van, C.P.},
	year = {2009},
	pages = {77--96},
}

@incollection{knottEcologyFemaleReproduction2009,
	address = {New York},
	title = {The ecology of female reproduction in wild orangutans},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {{ORANGUTANS}: {GEOGRAPHIC} {VARIATION} {IN} {BEHAVIORAL} {ECOLOGY} {AND} {CONSERVATION}},
	publisher = {Oxford Univ Press},
	author = {Knott, C. D. and Emery Thompson, M. and Wich, S. A.},
	year = {2009},
	pages = {171--188},
}

@incollection{marshallEffectsForestPhenology2009,
	address = {New York},
	title = {The effects of forest phenology and floristics on populations of {Bornean} and {Sumatran} orangutans},
	booktitle = {Orangutans: {Geographic} variation in behavioral ecology and conservation},
	publisher = {Oxford University Press},
	author = {Marshall, A. J. and Ancrenaz, M. and Brearley, F. Q. and Fredriksson, G. M. and Ghaffar, N. and Heydon, M. and Husson, S. J. and Leighton, M. and McCOnkey, K. R. and Morrogh-Bernard, H. C. and Proctor, J. and Schaik, C. P. van and Yeager, C. and Wich, S. A.},
	editor = {Wich, S. A. and Utami Atmoko, S. S. and Mitra Setia, T. and Schaik, C. P. van},
	year = {2009},
	pages = {97--118},
}

@incollection{marshallOrangutanPopulationBiology2009,
	address = {New York},
	title = {Orangutan population biology, life history, and conservation},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {Orangutans: {Geographic} variation in behavioral ecology and conservation},
	publisher = {Oxford Univ Press},
	author = {Marshall, A. J. and Lacy, R. and Ancrenaz, M. and Byers, O. and Husson, S. J. and Leighton, M. and Meijaard, E. and Rosen, N. and Singleton, I. and Stephens, S. and Traylor-Holzer, K. and Utami Atmoko, S. S. and van Schaik, C. P. and Wich, S. A.},
	year = {2009},
	pages = {311--326},
}

@incollection{morrogh-bernardOrangutanActivityBudgets2009,
	address = {New York},
	title = {Orangutan activity budgets and diet: a comparison between species, populations and habitats},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {{ORANGUTANS}: {GEOGRAPHIC} {VARIATION} {IN} {BEHAVIORAL} {ECOLOGY} {AND} {CONSERVATION}},
	publisher = {Oxford Univ Press},
	author = {Morrogh-Bernard, H. C. and Husson, S. J. and Knott, C. D. and Wich, S. A. and van Schaik, C. P. and van Hoordwijk, M. A. and Lackman-Ancrenaz, I. and Marshall, A. J. and Kanamori, T. and Kuze, N. and Sakong, R. B.},
	year = {2009},
	pages = {119--133},
}

@incollection{prasetyoNestBuildingOrangutans2009,
	address = {New York},
	title = {Nest building in orangutans},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {Orangutans: {Geographic} variation in behavioural ecology and conservation},
	publisher = {Oxford Univ Press},
	author = {Prasetyo, D. and Ancrenaz, M. and Morrogh-Bernard, H. C. and Utami Atmoko, S. S. and Wich, S. A. and van Schaik, C. P.},
	year = {2009},
	pages = {269--277},
}

@incollection{russonGeographicVariationOrangutan2009,
	address = {New York},
	title = {Geographic variation in orangutan diets},
	booktitle = {Orangutans: {Geographic} variation in behavioral ecology and conservation},
	publisher = {Oxford University Press},
	author = {Russon, A. R. and Wich, S. A. and Ancrenaz, M. and Kanamori, T. and Knott, C. D. and Kuze, N. and Morrogh-Bernard, H. C. and Pratje, P. and Ramlee, H. and Rodman, P. and Sawang, A. and Sidiyasa, K. and Singleton, I. and Van  Schaik, C. P.},
	editor = {Wich, S. A. and Utami Atmoko, S. S. and Mitra Setia, T. and Van  Schaik, C. P.},
	year = {2009},
	pages = {135--155},
}

@incollection{singletonRangingBehaviorOrangutan2009,
	address = {New York},
	title = {Ranging behavior of orangutan females and social organization},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {Orangutans: {Geographic} variation in behavioiral ecology and conservation},
	publisher = {Oxford Univ Press},
	author = {Singleton, I. and Knott, C. D. and Morrogh-Bernard, H. C. and Wich, S. A. and van Schaik, C. P.},
	year = {2009},
	pages = {205--213},
}

@incollection{vanschaikGeographicVariationOrangutan2009,
	address = {New York},
	title = {Geographic variation in orangutan behavior and biology},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	booktitle = {{ORANGUTANS}: {GEOGRAPHIC} {VARIATION} {IN} {BEHAVIORAL} {ECOLOGY} {AND} {CONSERVATION}},
	publisher = {Oxford Univ Press},
	author = {van Schaik, C. P. and Marshall, A. J. and Wich, S. A.},
	year = {2009},
	pages = {351--361},
}

@incollection{wichOrangutanLifeHistory2009,
	address = {New York},
	title = {Orangutan life history variation},
	booktitle = {Orangutans: {Geographic} variation in behavioral ecology and conservation},
	publisher = {Oxford University Press},
	author = {Wich, S. A. and de Vries, H. and Ancrenaz, M. and Perkins, L. and Shumaker, R.W. and Suzuki, A. and van  Schaik, C. P.},
	editor = {Wich, S. A. and Utami Atmoko, S. S. and Mitra Setia, T. and van  Schaik, C. P.},
	year = {2009},
	pages = {65--75},
}

@article{wichCaptiveWildOrangutan2009,
	title = {Captive and wild orangutan ({Pongo} sp.) survivorship: a comparison and the influence of management},
	volume = {71(8)},
	issn = {1098-2345(e)},
	journal = {American Journal of Primatology},
	author = {Wich, S. A. and Shumaker, R. W. and Perkins, L. and de Vries, H.},
	year = {2009},
	pages = {680--686},
}

@article{wichCaseSpontaneousAcquisition2009,
	title = {A case of spontaneous acquisition of a human sound by an orangutan},
	volume = {50(1)},
	issn = {0032-8332},
	journal = {Primates},
	author = {Wich, S. A. and Swartz, K. B. and Hardus, M. E. and Lameira, A. R. and Stromberg, E. and Shumaker, R. W.},
	year = {2009},
	pages = {56--64},
}

@book{wichOrangutansGeographicVariation2009,
	address = {New York},
	title = {Orangutans: {Geographic} variation in behavioral ecology and conservation},
	isbn = {978-0-19-921327-6 0-19-921327-5},
	publisher = {Oxford Univ Press},
	author = {Wich, S. A. and Utami Atmoko, S. S. and Mitra Setia, T. and van Schaik, C. P.},
	year = {2009},
}

@article{wichGeographicVariationOrangutan2009,
	title = {Geographic variation in orangutan calls: implications for the evolution of language?},
	volume = {(Suppl 48)},
	issn = {0002-9483},
	journal = {American Journal of Physical Anthropology},
	author = {Wich, S. A. and van Schaik, C. P.},
	year = {2009},
	pages = {271--272},
}

@article{willemsEnvironmentalCausesGeographic2009,
	title = {Environmental causes of geographic variation between populations of wild orang-utans ({Pongo} sp.)},
	volume = {80(2)},
	issn = {0015-5713},
	journal = {Folia Primatologica},
	author = {Willems, E. P. and Wich, S. A. and Marshall, A. J. and van Schaik, C. P.},
	year = {2009},
	pages = {150},
}

@article{bastianGeographicVariationWild2008,
	title = {Geographic variation in wild orangutan diet: evidence for social learning},
	volume = {Suppl 46},
	issn = {0002-9483},
	journal = {American Journal of Physical Anthropology},
	author = {Bastian, M. L. and Zweifel, N. and Vogel, E. R. and Wich, S. A. and van Schaik, C. P.},
	year = {2008},
	pages = {64--65},
}

@article{hardusModificationAcousticCall2008,
	title = {Modification of acoustic call variables through the use of hands and tools in wild orangutans},
	volume = {96(Sp CD-ROM iss - IPS 2008)},
	journal = {Primate Eye},
	author = {Hardus, M. E. and Lameira, A. R. and van Schaik, C. P. and Wich, S. A.},
	year = {2008},
	pages = {Abst \#670},
}

@article{lameiraGeographicVariationFunctionally2008,
	title = {Geographic variation in functionally equivalent calls in wild orangutans},
	volume = {96(Sp CD-ROM iss - IPS 2008)},
	journal = {Primate Eye},
	author = {Lameira, A. R. and Hardus, M. E. and Naso, A. and van Schaik, C. P. and Wich, S. A.},
	year = {2008},
	pages = {Abst \#671},
}

@article{lameiraOrangutanLongCall2008,
	title = {Orangutan long call degradation and individuality through distance: a playback approach},
	issn = {0164-0291},
	number = {29(3)},
	journal = {International Journal of Primatology},
	author = {Lameira, A. R. and Wich, S. A.},
	year = {2008},
	pages = {615--625},
}

@incollection{shumakerReproductiveLifeHistory2008,
	address = {Basel},
	title = {Reproductive life history traits of female orangutans ({Pongo} spp.)},
	isbn = {9783805585224; 9783805585231(e) 0074-1132},
	booktitle = {Primate reproductive aging: {Cross}-taxon perspectives on reproduction},
	publisher = {Karger},
	author = {Shumaker, R. W. and Wich, S. A. and Perkins, L.},
	year = {2008},
	pages = {147--161},
}

@article{stewartFishingMacacaFascicularis2008,
	title = {Fishing in {Macaca} fascicularis: {A} rarely observed innovative behavior},
	issn = {0164-0291},
	number = {29(2)},
	journal = {International Journal of Primatology},
	author = {Stewart, A. M. E. and Gordon, C. H. and Wich, S. A. and Schroor, P. and Meijaard, E.},
	year = {2008},
	pages = {543--548},
}

@article{vogelFactorsAffectingForaging2008,
	title = {Factors affecting foraging decisions in a wild population of sympatric orangutans ({Pongo} pygmaeus wurmbii) and white-bearded gibbons ({Hylobates} albibarbis): evidence of cognitive maps},
	volume = {Suppl 46},
	issn = {0002-9483},
	journal = {American Journal of Physical Anthropology},
	author = {Vogel, E. R. and Haag, L. and Wich, S. A. and Bastian, M. L. and van Schaik, C. P.},
	year = {2008},
	pages = {215},
}

@article{wichDistributionConservationStatus2008,
	title = {Distribution and conservation status of the orang-utan ({Pongo} spp.) on {Borneo} and {Sumatra}: how many remain?},
	url = {http://journals.cambridge.org/action/displayIssue?jid=ORX&volumeId=42&issueId=03},
	number = {42(3)},
	journal = {Oryx},
	author = {Wich, S. A. and Meijaard, E. and Marshall, A. J. and Husson, S. and Ancrenaz, M. and Lacy, R. C. and van Schaik, C. P. and Sugardjito, J. and Simorangkir, T. and Traylor-Holzer, K. and Doughty, M. and Supriatna, J. and Dennis, R. and Gumal, M. and Knott, C. D. and Singleton, I.},
	year = {2008},
	pages = {329--339},
}

@article{wichGeographicVariationThomas2008,
	title = {Geographic variation in {Thomas} langur ({Presbytis} thomasi) loud calls},
	volume = {70(6)},
	issn = {0275-2565},
	journal = {American Journal of Primatology},
	author = {Wich, S. A. and Schel, A. M. and de Vries, H.},
	year = {2008},
	pages = {566--574},
}

@article{wichLearningVoluntaryProduction2008,
	title = {Learning and voluntary production and modification of a new sound in an orangutan},
	volume = {96(Sp CD-ROM iss - IPS 2008)},
	journal = {Primate Eye},
	author = {Wich, S. A. and Swartz, K. and Hardus, M. and Lameira, A. R. and Stromberg, E. and Shumaker, R. W.},
	year = {2008},
	pages = {Abst \#682},
}

@article{meijaardPuttingOrangutanPopulation2007,
	title = {Putting orang-utan population trends into perspective},
	volume = {17},
	journal = {Current Biology},
	author = {Meijaard, E. and Wich, S.A.},
	year = {2007},
	pages = {R540},
}

@article{mulIntestinalParasitesFreeranging2007,
	title = {Intestinal parasites of free-ranging, semicaptive, and captive {Pongo} abelii in {Sumatra}, {Indonesia}},
	volume = {28(2)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Mul, I. F. and Paembonan, W. and Singleton, I. and Wich, S. A. and van Bolhuis, H. G.},
	year = {2007},
	pages = {407--420},
}

@article{vanwoerdenPreliminaryAnalysisAssociations2007,
	title = {A preliminary analysis of associations and time budgets in wild orangutan females in the period preceding and following birth},
	volume = {(Suppl 44)},
	issn = {0002-9483},
	journal = {American Journal of Physical Anthropology},
	author = {van Woerden, J. T. and Vogel, E. R. and van Schaik, C. P. and Wich, S. A. and van Noordwijk, M. A.},
	year = {2007},
	pages = {236--237},
}

@article{wichDemographyLifeHistory2007,
	title = {Demography and life history of {Thomas} langurs ({Presbytis} thomasi)},
	volume = {69(6)},
	issn = {0275-2565},
	journal = {American Journal of Primatology},
	author = {Wich, S. A. and Steenbeek, R. and Sterck, E. H. M. and Korstjens, A. H. and Willems, E. P. and Van Schaik, C. P.},
	year = {2007},
	pages = {641--651},
}

@article{wichFamiliarityThreatOpponents2007,
	title = {Familiarity and threat of opponents determine variation in {Thomas} langur ({Presbytis} thomasi) male behaviour during between-group encounters},
	volume = {144(12)},
	issn = {0005-7959},
	journal = {Behaviour},
	author = {Wich, S. A. and Sterck, E. H. M.},
	year = {2007},
	pages = {1583--1598},
}

@article{marvinIntegratingTechnologiesScalable07,
	title = {Integrating technologies for scalable ecology and conservation},
	volume = {7},
	issn = {2351-9894},
	url = {http://www.sciencedirect.com/science/article/pii/S2351989416300592},
	doi = {10.1016/j.gecco.2016.07.002},
	abstract = {Integration of multiple technologies greatly increases the spatial and temporal scales over which ecological patterns and processes can be studied, and threats to protected ecosystems can be identified and mitigated. A range of technology options relevant to ecologists and conservation practitioners are described, including ways they can be linked to increase the dimensionality of data collection efforts. Remote sensing, ground-based, and data fusion technologies are broadly discussed in the context of ecological research and conservation efforts. Examples of technology integration across all of these domains are provided for large-scale protected area management and investigation of ecological dynamics. Most technologies are low-cost or open-source, and when deployed can reach economies of scale that reduce per-area costs dramatically. The large-scale, long-term data collection efforts presented here can generate new spatio-temporal understanding of threats faced by natural ecosystems and endangered species, leading to more effective conservation strategies.},
	journal = {Global Ecology and Conservation},
	author = {Marvin, David C. and Koh, Lian Pin and Lynam, Antony J. and Wich, Serge and Davies, Andrew B. and Krishnamurthy, Ramesh and Stokes, Emma and Starkey, Ruth and Asner, Gregory P.},
	year = {2007},
	pages = {262--275},
}

Integration of multiple technologies greatly increases the spatial and temporal scales over which ecological patterns and processes can be studied, and threats to protected ecosystems can be identified and mitigated. A range of technology options relevant to ecologists and conservation practitioners are described, including ways they can be linked to increase the dimensionality of data collection efforts. Remote sensing, ground-based, and data fusion technologies are broadly discussed in the context of ecological research and conservation efforts. Examples of technology integration across all of these domains are provided for large-scale protected area management and investigation of ecological dynamics. Most technologies are low-cost or open-source, and when deployed can reach economies of scale that reduce per-area costs dramatically. The large-scale, long-term data collection efforts presented here can generate new spatio-temporal understanding of threats faced by natural ecosystems and endangered species, leading to more effective conservation strategies.

@article{knottEcologyReproductionWild2006,
	title = {The ecology of reproduction in wild orangutans},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Knott, C. and Wich, S.},
	year = {2006},
	pages = {Abst \#388},
}

@article{marshallEffectsHabitatQuality2006,
	title = {The effects of habitat quality, phenology, and floristics on populations of {Bornean} and {Sumatran} orangutans: are {Sumatran} forests more productive than {Bornean} forests?},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Marshall, A. J. and Ancrenaz, M. and Fredriksson, G. and Ghaffar, N. and Leighton, M. and McConkey, K. R. and Morrogh-Bernard, H. and van Schaik, C. P. and Yeager, C. P. and Wich, S. A. and Proctor, J. and Brearley, F.},
	year = {2006},
	pages = {Abst \#381},
}

@article{russonGeographicVariationOrangutan2006,
	title = {Geographic variation in orangutan diet},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Russon, A. and Wich, S. and Ancrenaz, M. and Morrogh-Berenard, H. and Knott, C. and Pratje, P. and Ramlee, H. and Rodman, P. and Singleton, I.},
	year = {2006},
	pages = {Abst \#384},
}

@article{singletonRangingBehaviourOrangutans2006,
	title = {Ranging behaviour of orangutans, an appraisal of existing knowledge},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Singleton, I. and Wich, S. A. and van Schaik, C. P. and Knott, C. D.},
	year = {2006},
	pages = {Abst \#393},
}

@article{snaithDietaryRangingResponses2006,
	title = {Dietary and ranging responses of orangutans to fluctuating food availability},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Snaith, T. and Knott, C. and Wich, S. and Singleton, I.},
	year = {2006},
	pages = {Abst \#385},
}

@article{utamiatmokoFoodCompetitionWild2006,
	title = {Food competition in wild female orangutans ({Pongo} abelii) in {Ketambe}, {Gunung} {Leuser} {National} {Park}, {Sumatra}, {Indonesia}},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Utami Atmoko, S. and Wich, S. A. and Berents, M. and Meijer, R.},
	year = {2006},
	pages = {Abst \#376},
}

@article{vanadrichemDevelopmentWildImmature2006,
	title = {The development of wild immature {Sumatran} orangutans ({Pongo} abelii) at {Ketambe}},
	volume = {47(4)},
	issn = {0032-8332},
	journal = {Primates},
	author = {van Adrichem, G. G. J. and Utami, S. S. and Wich, S. A. and van Hooff, Jaram and Sterck, E. H. M.},
	year = {2006},
	pages = {300--309},
}

@article{vannoordwijkGrowingSlowlyDevelopment2006,
	title = {Growing up slowly? {Development} in {Sumatran} and {Bornean} orangutans},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {van Noordwijk, M. A. and Wich, S. A. and Utami Atmoko, S. and Knott, C. D.},
	year = {2006},
	pages = {Abst \#389},
}

@article{vanschaikOrangutanCulturesRevisited2006,
	title = {Orangutan cultures revisited},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {van Schaik, C. P. and Ancrenaz, M. and Knott, C. and Morrogh-Bernard, H. and Utami Atmoko, S. and Wich, S.},
	year = {2006},
	pages = {Abst \#396},
}

@article{vanschaikInnovationWildBornean2006,
	title = {Innovation in wild {Bornean} orangutans ({Pongo} pygmaeus wurmbii)},
	volume = {143},
	journal = {Behaviour},
	author = {van Schaik, C. P. and van Noordwijk, M. A. and Wich, S. A.},
	year = {2006},
	pages = {839--876},
}

@article{wichOrangutanLifeHistory2006,
	title = {Orangutan life history compared},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Wich, S.},
	year = {2006},
	pages = {Abst \#390},
}

@article{wichSymposiumOrangutansCompared2006,
	title = {Symposium: orangutans compared},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Wich, S. and Russon, A. and van Schaik, C.},
	year = {2006},
	pages = {Abst \#378},
}

@article{wichVocalSoundRepertoire2006,
	title = {Vocal and sound repertoire of orangutans compared},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Wich, S. and Singleton, I. and Utami, S. and Hardus, M. and Lameira, A.},
	year = {2006},
	pages = {Abst \#391},
}

@article{wichBetweengroupEncountersThomas2006,
	title = {Between-group encounters in {Thomas} langurs},
	volume = {27(Suppl 1)},
	issn = {0164-0291},
	journal = {International Journal of Primatology},
	author = {Wich, S. and Sterck, E.},
	year = {2006},
	pages = {Abst \#187},
}

@article{wichMaleMonkeysRemember2006,
	title = {Male monkeys remember which group members have given alarm calls},
	volume = {273},
	number = {1587},
	journal = {Procedings of the Royal Society of London},
	author = {Wich, S. A. and de Vries, H.},
	year = {2006},
	pages = {735--740},
}

@incollection{wichInfluenceFruitAvailability2006,
	address = {New York},
	title = {Influence of fruit availability on {Sumatran} orangutan sociality and reproduction},
	booktitle = {Feeding ecology in apes and other primates: {Ecological}, physical and behavioral aspects},
	publisher = {Cambridge Univ Press},
	author = {Wich, S. A. and Geurts, M. L. and Mitra Setia, T. and Utami-Atmoko, S. S.},
	year = {2006},
	pages = {337--358},
}

@article{wichDietaryEnergeticResponses2006,
	title = {Dietary and energetic responses of {Pongo} abelii to fruit availability fluctuations},
	number = {27(6)},
	journal = {International Journal of Primatology`},
	author = {Wich, S. A. and Utami-Atmoko, S. S. and Setia, T. M. and Djoyosudharmo, S. and Geurts, M. L.},
	year = {2006},
	pages = {1535--1550},
}

@article{sterckFemaleDispersalInbreeding2005,
	title = {Female dispersal, inbreeding avoidance and mate choice in {Thomas} langurs ({Presbytis} thomasi)},
	volume = {142},
	url = {://000232463800001},
	abstract = {Female social dispersal in primates differs from the general mammalian pattern of locational dispersal. Both nulliparous and parous females may disperse to another group. Several hypotheses can explain female social dispersal: reduction of predation risk, inbreeding avoidance, and offspring protection through mate choice. We tested these hypotheses with an extended data set of Thomas langurs (Presbytis thomasi) and investigated parameters of male behaviour that females may use in their dispersal decisions. Data were collected over a 12.5-year period from a wild population in Sumatra, Indonesia, allowing for some critical tests of the hypotheses. Females dispersed to a group smaller than their original one, thereby refuting the predation risk hypothesis. Maturing nulliparous females only dispersed when their father was resident. Therefore, dispersal by nulliparous females was best explained through inbreeding avoidance. Parous females transferred to young, adult males. These males provided better protection to offspring against predation and infanticide than the old, late tenure males. Therefore, females transfer to better protector males. The male behavioural cues that females use to assess male quality were unclear. Females, however, may use proxies of male age, such as group composition and acoustical characteristics of loud calls, as indicators of male quality. The results suggest that female mate choice is an important function of social dispersal by parous females. Its importance in locational dispersal remains to be investigated.},
	journal = {Behaviour},
	author = {Sterck, E. H. M. and Willems, E. P. and van Hooff, Jaram and Wich, S. A.},
	month = jul,
	year = {2005},
	pages = {845--868},
}

Female social dispersal in primates differs from the general mammalian pattern of locational dispersal. Both nulliparous and parous females may disperse to another group. Several hypotheses can explain female social dispersal: reduction of predation risk, inbreeding avoidance, and offspring protection through mate choice. We tested these hypotheses with an extended data set of Thomas langurs (Presbytis thomasi) and investigated parameters of male behaviour that females may use in their dispersal decisions. Data were collected over a 12.5-year period from a wild population in Sumatra, Indonesia, allowing for some critical tests of the hypotheses. Females dispersed to a group smaller than their original one, thereby refuting the predation risk hypothesis. Maturing nulliparous females only dispersed when their father was resident. Therefore, dispersal by nulliparous females was best explained through inbreeding avoidance. Parous females transferred to young, adult males. These males provided better protection to offspring against predation and infanticide than the old, late tenure males. Therefore, females transfer to better protector males. The male behavioural cues that females use to assess male quality were unclear. Females, however, may use proxies of male age, such as group composition and acoustical characteristics of loud calls, as indicators of male quality. The results suggest that female mate choice is an important function of social dispersal by parous females. Its importance in locational dispersal remains to be investigated.

@incollection{vanschaikRecognizingInnovationsField2005,
	address = {Leipzig},
	title = {Recognizing innovations in the field: a proposal for a procedure and a field test with {Bornean} orangutans},
	url = {http://www.eva.mpg.de/primat/Culture2005/index.html},
	booktitle = {{CULTURE} {CONFERENCE} 2005},
	publisher = {Max Planck Inst Evol Anthropol},
	author = {van Schaik, C. and Bastian, M. and Ramsey, G. and Wich, S. and van Noordwijk, M.},
	year = {2005},
	pages = {31},
}

@article{vanschaikSimpleAlternativeLine2005,
	title = {A simple alternative to line transects of nests for estimating orangutan densities},
	volume = {46},
	url = {://000232887900004},
	abstract = {We conducted a validation of the line transect technique to estimate densities of orangutan (Pongo pygmaeus) nests in a Bornean swamp forest, and compared these results with density estimates based on nest counts in plots and on female home ranges. First, we examined the accuracy of the line transect method. We found that the densities based on a pass in both directions of two experienced pairs of observers was 27\% below a combined sample based on transect walks by eight pairs of observers, suggesting that regular line-transect densities may seriously underestimate true densities. Second, we compared these results with those obtained by nest counts in 0.2-ha plots. This method produced an estimated 15.24 nests/ha, as compared to 10.0 and 10.9, respectively, by two experienced pairs of observers who walked a line transect in both directions. Third, we estimated orangutan densities based on female home range size and overlap and the proportion of females in the population, which produced a density of 4.25-4.5 individuals/km(2). Converting nest densities into orangutan densities, using locally estimated parameters for nest production rate and proportion of nest builders in the population, we found that density estimates based on the line transect results of the most experienced pairs on a double pass were 2.82 and 3.08 orangutans/km(2), based on the combined line transect data are 4.04, and based on plot counts are 4.30. In this swamp forest, plot counts therefore give more accurate estimates than do line transects. We recommend that this new method be evaluated in other forest types as well.},
	number = {4},
	journal = {Primates},
	author = {van Schaik, C. P. and Wich, S. A. and Utami, S. S. and Odom, K.},
	month = oct,
	year = {2005},
	pages = {249--254},
}

We conducted a validation of the line transect technique to estimate densities of orangutan (Pongo pygmaeus) nests in a Bornean swamp forest, and compared these results with density estimates based on nest counts in plots and on female home ranges. First, we examined the accuracy of the line transect method. We found that the densities based on a pass in both directions of two experienced pairs of observers was 27% below a combined sample based on transect walks by eight pairs of observers, suggesting that regular line-transect densities may seriously underestimate true densities. Second, we compared these results with those obtained by nest counts in 0.2-ha plots. This method produced an estimated 15.24 nests/ha, as compared to 10.0 and 10.9, respectively, by two experienced pairs of observers who walked a line transect in both directions. Third, we estimated orangutan densities based on female home range size and overlap and the proportion of females in the population, which produced a density of 4.25-4.5 individuals/km(2). Converting nest densities into orangutan densities, using locally estimated parameters for nest production rate and proportion of nest builders in the population, we found that density estimates based on the line transect results of the most experienced pairs on a double pass were 2.82 and 3.08 orangutans/km(2), based on the combined line transect data are 4.04, and based on plot counts are 4.30. In this swamp forest, plot counts therefore give more accurate estimates than do line transects. We recommend that this new method be evaluated in other forest types as well.

@article{boubliMesoscaleTransectSampling2004,
	title = {Mesoscale transect sampling of trees in the {Lomako}-{Yekokora} interfluvium, {Democratic} {Republic} of the {Congo}},
	volume = {13},
	url = {://000225178400002},
	abstract = {We conducted a mesoscale transect sampling of trees greater than or equal to 10 cm DBH in the Lomako Yekokora interfluvial forest, Democratic Republic of the Congo. Our objective was to characterize the forest landscape contained between the Lomako and Yekokora rivers in terms of its floristic composition and to investigate how representative the Lomako study site, the location of a long-term study of primates, was of the entire forest block. Fifteen transects were laid out at seven sample stations placed approximately 10 km apart and alongside a 70 km trail running from the Lomako study site to the margins of the Yekokora river. Three transects totaling 3.65 ha were laid out at the Lomako study site and two transects totaling 2 ha at each of the remaining six sample stations, amounting to 15.65 ha in total. Average DBH, tree density, tree species richness and floristic composition were determined for each transect. There were 5353 trees greater than or equal to 10 cm DBH in the total sample, representing 150 species in 35 families. Caesalpinoideae trees dominated the sample, followed by Olacaceae and Annonaceae. Four forest types were identified: mixed primary (57\% of the sampled plots), secondary forest (9\%), Gilbertiodendron (22\%), and swamp (12\%). The seven sample stations differed from each other in average DBH, tree density, tree species richness and floristic composition. Most of the difference, however, was due to the fact that the four forest types were not equally represented at each sample station. When forest types were contrasted independently, a marked difference in average DBH, tree density, tree species richness and floristic composition was recorded. Conversely, when only mixed primary forest was analyzed across the sample stations, no significant difference was detected except for average DBH. Thus the Lomako study site is representative of the forest landscape contained between the Lomako and Yekokora rivers only when the different forest types are treated separately. The sample stations ( including Lomako) differ from each other, however, in the proportional contribution of each forest type.},
	number = {13},
	journal = {Biodiversity and Conservation},
	author = {Boubli, J. P. and Eriksson, J. and Wich, S. and Hohmann, G. and Fruth, B.},
	month = dec,
	year = {2004},
	pages = {2399--2417},
}

We conducted a mesoscale transect sampling of trees greater than or equal to 10 cm DBH in the Lomako Yekokora interfluvial forest, Democratic Republic of the Congo. Our objective was to characterize the forest landscape contained between the Lomako and Yekokora rivers in terms of its floristic composition and to investigate how representative the Lomako study site, the location of a long-term study of primates, was of the entire forest block. Fifteen transects were laid out at seven sample stations placed approximately 10 km apart and alongside a 70 km trail running from the Lomako study site to the margins of the Yekokora river. Three transects totaling 3.65 ha were laid out at the Lomako study site and two transects totaling 2 ha at each of the remaining six sample stations, amounting to 15.65 ha in total. Average DBH, tree density, tree species richness and floristic composition were determined for each transect. There were 5353 trees greater than or equal to 10 cm DBH in the total sample, representing 150 species in 35 families. Caesalpinoideae trees dominated the sample, followed by Olacaceae and Annonaceae. Four forest types were identified: mixed primary (57% of the sampled plots), secondary forest (9%), Gilbertiodendron (22%), and swamp (12%). The seven sample stations differed from each other in average DBH, tree density, tree species richness and floristic composition. Most of the difference, however, was due to the fact that the four forest types were not equally represented at each sample station. When forest types were contrasted independently, a marked difference in average DBH, tree density, tree species richness and floristic composition was recorded. Conversely, when only mixed primary forest was analyzed across the sample stations, no significant difference was detected except for average DBH. Thus the Lomako study site is representative of the forest landscape contained between the Lomako and Yekokora rivers only when the different forest types are treated separately. The sample stations ( including Lomako) differ from each other, however, in the proportional contribution of each forest type.

@article{kitchenSubordinateMaleBlack2004,
	title = {Subordinate male black howler monkey ({Alouatta} pigra) responses to loud calls: experimental evidence for the effects of intra-group male relationships and age},
	number = {141(6)},
	journal = {BEHAVIOUR},
	author = {Kitchen, D. M. and Horwich, R. H. and James, R. A.},
	year = {2004},
	pages = {703--723},
}

@article{knopComparisonOrangutanDensity2004,
	title = {A comparison of orang-utan density in a logged and unlogged forest on {Sumatra}},
	volume = {120},
	number = {2},
	journal = {Biological Conservation},
	author = {Knop, E. and Ward, P.I. and Wich, S. A.},
	year = {2004},
	pages = {187--192},
}

@techreport{schaikvanStatusOrangutanIndonesia2004,
	address = {London, UK},
	title = {The status of the orangutan in {Indonesia}, 2003},
	institution = {Orangutan Foundation, UK},
	author = {Schaik van, C.P. and Husson, S. and Meijaard, E. and Singleton, I. and Wich, S. A.},
	year = {2004},
}

@techreport{shepherdOpenSeasonAnalysis2004,
	address = {Petaling Jaya, Malaysia},
	title = {Open season: {An} analysis of the pet trade in {Medan}, {Sumatra} 1997-2001},
	institution = {TRAFFIC Southeast Asia},
	author = {Shepherd, C. R. and Sukumaran, J. and Wich, S. A.},
	year = {2004},
}

@book{singletonOrangutanPopulationHabitat2004,
	address = {Apple Valley, MN},
	title = {Orangutan {Population} and {Habitat} {Viability} {Assessment}: {Final} {Report}},
	url = {http://www.cbsg.org/reports/reports/exec_sum/OrangutanPHVA04_LowRes.pdf},
	publisher = {IUCN/SSC Conservation Breeding Specialist Group},
	author = {Singleton, I. and Wich, S. and Husson, S. and Stephens, S. and Utami Atmoko, S. and Leighton, M. and Rosen, N. and Traylor-Holzer, K. and Lacy, R. and Byers, O.},
	year = {2004},
}

@article{wichDeterminantsOrangutanDensity2004,
	title = {Determinants of orangutan density in the dryland forests of the {Leuser} {Ecosystem}},
	volume = {45},
	url = {://000222756300003},
	abstract = {Orangutans are the only great ape in Asia. Since orangutan densities vary between habitat types within regions and within similar habitat types among regions, it is important to determine areas with high densities for their protection. In this paper we show that orangutan density in old-growth dryland forests in the Leuser Ecosystem, Sumatra is significantly related to the density of large strangling figs and topsoil pH. In addition, large fig density depends on topsoil pH. Provided that orangutans are present and no hunting or logging occur, topsoil pH seems a promising method for rapid assessment of potential orangutan density over large areas.},
	number = {3},
	journal = {Primates},
	author = {Wich, S. and Buij, R. and van Schaik, C.},
	month = jul,
	year = {2004},
	pages = {177--182},
}

Orangutans are the only great ape in Asia. Since orangutan densities vary between habitat types within regions and within similar habitat types among regions, it is important to determine areas with high densities for their protection. In this paper we show that orangutan density in old-growth dryland forests in the Leuser Ecosystem, Sumatra is significantly related to the density of large strangling figs and topsoil pH. In addition, large fig density depends on topsoil pH. Provided that orangutans are present and no hunting or logging occur, topsoil pH seems a promising method for rapid assessment of potential orangutan density over large areas.

@article{wichThomasLangursPresbytis2004,
	title = {Thomas langurs ({Presbytis} thomasi) discriminate between calls of young solitary versus older group-living males: {A} factor in avoiding infanticide?},
	volume = {141},
	url = {://000189260800004},
	abstract = {The ability to differentiate among calls from different individuals has been shown for a number of animal species and several functions have been suggested. One hypothesis, developed for lions (Panthera leo), is that the ability to distinguish between calls from neighbour versus strange males is linked to the avoidance of infanticidal (i.e. strange) males. Since infanticide is widespread among primates, we tested the applicability of this hypothesis to Thomas langurs (Presbytis thomasi). Young adult males, that mostly reside in all-male bands or are solitary (called AMB males), were more likely to be infanticidal than adult, usually older, males that reside in mixed-sex groups (called MSG males). We use playbacks to demonstrate that Thomas langurs are able to differentiate between loud calls from AMB male strangers and MSG male strangers. Thomas langur males responded more vigorously to playbacks of calls from AMB (i.e. more likely to be infanticidal) males than to calls from MSG males. Females showed a more cautious response to the calls from AMB males than to the calls from MSG males. Both these reactions are in accordance with the infanticide hypothesis and suggest that Thomas langurs differentiate between loud calls of AMB and MSG stranger males and incorporate this information in their behaviour to avoid infanticide.},
	journal = {Behaviour},
	author = {Wich, S. A. and Assink, P. R. and Sterck, E. H. M.},
	month = jan,
	year = {2004},
	pages = {41--51},
}

The ability to differentiate among calls from different individuals has been shown for a number of animal species and several functions have been suggested. One hypothesis, developed for lions (Panthera leo), is that the ability to distinguish between calls from neighbour versus strange males is linked to the avoidance of infanticidal (i.e. strange) males. Since infanticide is widespread among primates, we tested the applicability of this hypothesis to Thomas langurs (Presbytis thomasi). Young adult males, that mostly reside in all-male bands or are solitary (called AMB males), were more likely to be infanticidal than adult, usually older, males that reside in mixed-sex groups (called MSG males). We use playbacks to demonstrate that Thomas langurs are able to differentiate between loud calls from AMB male strangers and MSG male strangers. Thomas langur males responded more vigorously to playbacks of calls from AMB (i.e. more likely to be infanticidal) males than to calls from MSG males. Females showed a more cautious response to the calls from AMB males than to the calls from MSG males. Both these reactions are in accordance with the infanticide hypothesis and suggest that Thomas langurs differentiate between loud calls of AMB and MSG stranger males and incorporate this information in their behaviour to avoid infanticide.

@article{wichLifeHistoryWild2004,
	title = {Life history of wild {Sumatran} orangutans ({Pongo} abelii)},
	volume = {47(6)},
	issn = {0047-2484},
	journal = {Journal of Human Evolution},
	author = {Wich, S. A. and Utami-Atmoko, S. S. and Mitra Setia, T. and Rijksen, H. D. and Schurmann, C. and van Hooff, Jaram and van Schaik, C. P.},
	year = {2004},
	pages = {385--398},
}

@article{wichIndividualContextualVariation2003,
	title = {Individual and contextual variation in {Thomas} langur male loud calls},
	volume = {109},
	url = {://000179946500001},
	abstract = {Individual and contextual differences in male loud calls of wild Thomas langurs (Presbytis thomasi ) were studied in northern Sumatra, Indonesia. Loud calls were given in the following contexts: morning calls, vocal responses to other groups, between-group encounter calls and alarm calls. Loud call spectrograms were analysed for a large number of variables. With discriminant analyses, 14 variables were found to be important in distinguishing individuals and contexts. Loud calls were assigned to the correct individual in 95.6\% of the cases (91.8\% with 'leave-one-out' validation) and to the correct context in 52.2\% of the cases (39.0\% with 'leave-one- out' validation). Further analyses with two-way anovas showed significant differences in both temporal and frequency variables between individuals and contexts. Loud calls seemed to differ between the contexts in functionally meaningful ways, relating to the distance of the intended receivers and to the urgency of the message. Observation showed that females in the caller's group collected infants more often in the between- group encounter context and in the alarm call context than in the vocal exchange context. These differential responses suggest that the monkeys also perceive the measurable differences in loud call characteristics between the various contexts.},
	number = {1},
	journal = {Ethology},
	author = {Wich, S. A. and Koski, S. and de Vries, H. and van Schaik, C. P.},
	month = jan,
	year = {2003},
	pages = {1--13},
}

Individual and contextual differences in male loud calls of wild Thomas langurs (Presbytis thomasi ) were studied in northern Sumatra, Indonesia. Loud calls were given in the following contexts: morning calls, vocal responses to other groups, between-group encounter calls and alarm calls. Loud call spectrograms were analysed for a large number of variables. With discriminant analyses, 14 variables were found to be important in distinguishing individuals and contexts. Loud calls were assigned to the correct individual in 95.6% of the cases (91.8% with 'leave-one-out' validation) and to the correct context in 52.2% of the cases (39.0% with 'leave-one- out' validation). Further analyses with two-way anovas showed significant differences in both temporal and frequency variables between individuals and contexts. Loud calls seemed to differ between the contexts in functionally meaningful ways, relating to the distance of the intended receivers and to the urgency of the message. Observation showed that females in the caller's group collected infants more often in the between- group encounter context and in the alarm call context than in the vocal exchange context. These differential responses suggest that the monkeys also perceive the measurable differences in loud call characteristics between the various contexts.

@article{wichStatusSumatranOrangutan2003,
	title = {The status of the {Sumatran} orang-utan {Pongo} abelii: an update},
	volume = {37},
	url = {://000182554500018},
	abstract = {The Sumatran orang-utan Pongo abelii is categorized as Critically Endangered on the 2002 IUCN Red List. Although several reports have suggested that the species occurs in the region to the south of Lake Toba in Sumatra, Indonesia, their distribution is poorly known. In order to determine whether orang-utans still occur in this region we surveyed areas in which orangutans have been reported as well as a number of other forested areas. Orang-utan signs were found in only two areas. This indicates that habitat loss and hunting have recently caused local extinctions. We combine these results with other available information to provide a summary of the current distribution of P. abelii in Sumatra and, based on our surveys, previous population estimates, and estimates of losses, we speculate that only c. 3,500 orangutans still occur in the wild in Sumatra at the end of 2002.},
	number = {1},
	journal = {Oryx},
	author = {Wich, S. A. and Singleton, I. and Utami-Atmoko, S. S. and Geurts, M. L. and Rijksen, H. D. and van Schaik, C. P.},
	month = jan,
	year = {2003},
	pages = {49--54},
}

The Sumatran orang-utan Pongo abelii is categorized as Critically Endangered on the 2002 IUCN Red List. Although several reports have suggested that the species occurs in the region to the south of Lake Toba in Sumatra, Indonesia, their distribution is poorly known. In order to determine whether orang-utans still occur in this region we surveyed areas in which orangutans have been reported as well as a number of other forested areas. Orang-utan signs were found in only two areas. This indicates that habitat loss and hunting have recently caused local extinctions. We combine these results with other available information to provide a summary of the current distribution of P. abelii in Sumatra and, based on our surveys, previous population estimates, and estimates of losses, we speculate that only c. 3,500 orangutans still occur in the wild in Sumatra at the end of 2002.

@article{wichPossibleAudienceEffect2003,
	title = {Possible audience effect in {Thomas} {Langurs} ({Primates}; {Presbytis} thomasi): {An} experimental study on male loud calls in response to a tiger model},
	volume = {60},
	url = {://000185024800003},
	abstract = {Recent research indicates that animal vocalizations can refer to objects in the outside world, and that call production may be controlled by the sender depending on the type of audience involved. Our research on wild male Thomas langurs (Primates: Presbytis thomasi) shows that these males call as a response to a tiger model when they are in a group, but do not call when they are solitary. This is the first experimental study on wild primates to demonstrate that the presence or absence of an audience influences calling behavior. Our results indicate that males in mixed-sex groups give more loud calls than solitary males when exposed to a predator model. This suggests that giving loud calls in response to predators is not purely a reflex and may be controlled in some way by the sender. (C) 2003 Wiley-Liss, Inc.},
	number = {4},
	journal = {American Journal of Primatology},
	author = {Wich, S. A. and Sterck, E. H. M.},
	month = aug,
	year = {2003},
	pages = {155--159},
}

Recent research indicates that animal vocalizations can refer to objects in the outside world, and that call production may be controlled by the sender depending on the type of audience involved. Our research on wild male Thomas langurs (Primates: Presbytis thomasi) shows that these males call as a response to a tiger model when they are in a group, but do not call when they are solitary. This is the first experimental study on wild primates to demonstrate that the presence or absence of an audience influences calling behavior. Our results indicate that males in mixed-sex groups give more loud calls than solitary males when exposed to a predator model. This suggests that giving loud calls in response to predators is not purely a reflex and may be controlled in some way by the sender. (C) 2003 Wiley-Liss, Inc.

@article{wichLifephaseRelatedChanges2003,
	title = {Life-phase related changes in male loud call characteristics and testosterone levels in wild {Thomas} langurs},
	volume = {24},
	url = {://000186895400008},
	abstract = {Males in many primate species give loud calls. Lifetime changes in loud calls may be due to either age or social changes. We examined loud call characteristics, loud call production and levels of fecal testosterone among 4 life-phases of male Thomas langurs (Presbytis thomasi): all-male band (AMB), early, middle, and late life-phase in mixed-sex groups. Discriminant analyses showed that a high percentage of loud calls could be assigned correctly to the proper life-phase. The most significant change in loud call characteristics is an increase in tonal units and duration from the AMB to the early life-phase, accompanied by a decrease in non-tonal units. Since adult AMB males have a similar age to that of early life-phase males, we suggest that social rather than age-related changes underlie the loud call differences between AMB males and early life-phase males. This could also be related to the increase in testosterone levels from the AMB to the early life-phase. In addition, we postulate that females may use loud call characteristics as a cue to choose between young and old males once they decided to leave their current male, and possibly also as a cue to decide to leave their current male as he enters his late life-phase.},
	number = {6},
	journal = {International Journal of Primatology},
	author = {Wich, S. A. and van der Post, D. J. and Heistermann, M. and Mohle, U. and van Hooff, Jaram and Sterck, E. H. M.},
	month = dec,
	year = {2003},
	pages = {1251--1265},
}

Males in many primate species give loud calls. Lifetime changes in loud calls may be due to either age or social changes. We examined loud call characteristics, loud call production and levels of fecal testosterone among 4 life-phases of male Thomas langurs (Presbytis thomasi): all-male band (AMB), early, middle, and late life-phase in mixed-sex groups. Discriminant analyses showed that a high percentage of loud calls could be assigned correctly to the proper life-phase. The most significant change in loud call characteristics is an increase in tonal units and duration from the AMB to the early life-phase, accompanied by a decrease in non-tonal units. Since adult AMB males have a similar age to that of early life-phase males, we suggest that social rather than age-related changes underlie the loud call differences between AMB males and early life-phase males. This could also be related to the increase in testosterone levels from the AMB to the early life-phase. In addition, we postulate that females may use loud call characteristics as a cue to choose between young and old males once they decided to leave their current male, and possibly also as a cue to decide to leave their current male as he enters his late life-phase.

@article{brunAnalysisDeforestationProtected03,
	title = {Analysis of deforestation and protected area effectiveness in {Indonesia}: {A} comparison of {Bayesian} spatial models},
	volume = {31},
	issn = {0959-3780},
	url = {http://www.sciencedirect.com/science/article/pii/S0959378015000230},
	doi = {10.1016/j.gloenvcha.2015.02.004},
	abstract = {Tropical deforestation in Southeast Asia is one of the leading causes of carbon emissions and reductions of biodiversity. Spatially explicit analyses of the dynamics of deforestation in Indonesia are needed to support sustainable land use planning but the value of such analyses has so far been limited by data availability and geographical scope. We use remote sensing maps of land use change from 2000 to 2010 to compare Bayesian computational models: autologistic and von Thünen spatial-autoregressive models. We use the models to analyze deforestation patterns in Indonesia and the effectiveness of protected areas. Cross-validation indicated that models had an accuracy of 70–85\%. We find that the spatial pattern of deforestation is explained by transport cost, agricultural rent and history of nearby illegal logging. The effectiveness of protected areas presented mixed results. After controlling for multiple confounders, protected areas of category Ia, exclusively managed for biodiversity conservation, were shown to be ineffective at slowing down deforestation. Our results suggest that monitoring and prevention of road construction within protected areas, using logging concessions as buffers of protected areas and geographical prioritization of control measures in illegal logging hotspots would be more effective for conservation than reliance on protected areas alone, especially under food price increasing scenarios.},
	number = {0},
	journal = {Global Environmental Change},
	author = {Brun, Cyrille and Cook, Alex R. and Lee, Janice Ser Huay and Wich, Serge A. and Koh, Lian Pin and Carrasco, Luis R.},
	year = {2003},
	pages = {285--295},
}

Tropical deforestation in Southeast Asia is one of the leading causes of carbon emissions and reductions of biodiversity. Spatially explicit analyses of the dynamics of deforestation in Indonesia are needed to support sustainable land use planning but the value of such analyses has so far been limited by data availability and geographical scope. We use remote sensing maps of land use change from 2000 to 2010 to compare Bayesian computational models: autologistic and von Thünen spatial-autoregressive models. We use the models to analyze deforestation patterns in Indonesia and the effectiveness of protected areas. Cross-validation indicated that models had an accuracy of 70–85%. We find that the spatial pattern of deforestation is explained by transport cost, agricultural rent and history of nearby illegal logging. The effectiveness of protected areas presented mixed results. After controlling for multiple confounders, protected areas of category Ia, exclusively managed for biodiversity conservation, were shown to be ineffective at slowing down deforestation. Our results suggest that monitoring and prevention of road construction within protected areas, using logging concessions as buffers of protected areas and geographical prioritization of control measures in illegal logging hotspots would be more effective for conservation than reliance on protected areas alone, especially under food price increasing scenarios.

@article{buijSeasonalMovementsSumatran2002,
	title = {Seasonal movements in the {Sumatran} orangutan ({Pongo} pygmaeus abelii) and consequences for conservation},
	volume = {107},
	url = {://000176659500008},
	abstract = {Preservation of orangutan habitat can only be effective when their range requirements are taken into consideration. Here, the effect of the variation in fruit supply at different altitudes on the seasonal movements of orangutans is investigated. Transects were surveyed every 2 months from 1998 to 2000, at different altitudinal zones in the larger Ketambe area, Indonesia. The density of orangutan and sources of ripe fruit with soft pulp were determined along these transects. Both orangutan density and the availability of fruit varied considerably throughout the survey period at different altitudinal zones. The peaks in fruit production at different altitudes occurred in successive periods. For each altitudinal zone a significant correlation was found between orangutan density and the number of fruit sources, which shows that orangutans follow the production of fruit between these altitudinal zones within the boundaries of their home range. Orangutans with core areas in intermediate and highland areas depend seasonally on fruit production of lowland areas, and vice versa. Thus, conservation of large tracts of primary forest with a range of different altitudes is necessary to preserve the remaining orangutan population. (C) 2002 Elsevier Science Ltd. All rights reserved.},
	number = {1},
	journal = {Biological Conservation},
	author = {Buij, R. and Wich, S. A. and Lubis, A. H. and Sterck, E. H. M.},
	month = sep,
	year = {2002},
	pages = {83--87},
}

Preservation of orangutan habitat can only be effective when their range requirements are taken into consideration. Here, the effect of the variation in fruit supply at different altitudes on the seasonal movements of orangutans is investigated. Transects were surveyed every 2 months from 1998 to 2000, at different altitudinal zones in the larger Ketambe area, Indonesia. The density of orangutan and sources of ripe fruit with soft pulp were determined along these transects. Both orangutan density and the availability of fruit varied considerably throughout the survey period at different altitudinal zones. The peaks in fruit production at different altitudes occurred in successive periods. For each altitudinal zone a significant correlation was found between orangutan density and the number of fruit sources, which shows that orangutans follow the production of fruit between these altitudinal zones within the boundaries of their home range. Orangutans with core areas in intermediate and highland areas depend seasonally on fruit production of lowland areas, and vice versa. Thus, conservation of large tracts of primary forest with a range of different altitudes is necessary to preserve the remaining orangutan population. (C) 2002 Elsevier Science Ltd. All rights reserved.

@incollection{lubisPopulationEstimatesSeasonal2002,
	address = {Beijing},
	title = {Population estimates and seasonal movement in the {Sumatran} orangutan ({Pongo} abelii)},
	booktitle = {{CARING} {FOR} {PRIMATES}. {ABSTRACTS} {OF} {THE} {XIXTH} {CONGRESS}. {THE} {INTERNATIONAL} {PRIMATOLOGICAL} {SOCIETY}},
	publisher = {Mammalogical Society of China},
	author = {Lubis, A. H. and Wich, S. A. and Sterck, E. H. M. and Buij, R.},
	year = {2002},
	pages = {231--232},
}

@incollection{singletonUpdateSumatranOrangutan2002,
	address = {Beijing},
	title = {An update on {Sumatran} orangutan distribution, ranging behaviour oand social organisation},
	booktitle = {{CARING} {FOR} {PRIMATES}. {ABSTRACTS} {OF} {THE} {XIXTH} {CONGRESS}. {THE} {INTERNATIONAL} {PRIMATOLOGICAL} {SOCIETY}},
	publisher = {Mammalogical Society of China},
	author = {Singleton, I. and Wich, S. and van Schaik, C. and Utami-Atmoki, S. S. and Rijksen, H.},
	year = {2002},
	pages = {213},
}

@phdthesis{wichStructureFunctionThomas2002,
	address = {Utrecht},
	type = {{PhD}},
	title = {The {Structure} and {Function} of {Thomas} {Langur} {Loud} {Calls}},
	school = {Utrecht University},
	author = {Wich, S. A.},
	year = {2002},
	note = {Publication Title: Behavioural Biology},
}

@article{wichPlaybacksLoudCalls2002a,
	title = {Playbacks of loud calls to wild {Thomas} langurs ({Primates}; {Presbytis} thomasi): {The} effect of location},
	volume = {139},
	url = {://000175684300005},
	abstract = {Animals may behave aggressively towards neighbours. For several bird species it has been shown that males react more vigorously towards calls of neighbours from the centre of their home range than from the edge. This is usually explained by assuming that the centre of a home range is of higher value to a male than the edge. To test these ideas for a primate species, we conducted experiments with playbacks of loud calls on wild male and female Thomas langurs (Presbytis thomasi). These animals may defend resources in their range or protect their offspring from infanticide and males may defend their females. In natural situations between-group encounters in the centre of a home range by the intruding neighbour are more often accompanied by infanticidal attempts than encounters at the edge. Loud calls of neighbours played back from the centre of the home range caused a more vigorous reaction from the resident male than calls from the edge. However, males in food-containing trees did not respond differently to edge playbacks from males in non-food-containing trees. Although males seem to defend resources and not mates, male behaviour may be best explained by defence of infants against infanticide. Female behaviour is best explained by resource defence.},
	journal = {Behaviour},
	author = {Wich, S. A. and Assink, P. R. and Becher, F. and Sterck, E. H. M.},
	month = jan,
	year = {2002},
	pages = {65--78},
}

Animals may behave aggressively towards neighbours. For several bird species it has been shown that males react more vigorously towards calls of neighbours from the centre of their home range than from the edge. This is usually explained by assuming that the centre of a home range is of higher value to a male than the edge. To test these ideas for a primate species, we conducted experiments with playbacks of loud calls on wild male and female Thomas langurs (Presbytis thomasi). These animals may defend resources in their range or protect their offspring from infanticide and males may defend their females. In natural situations between-group encounters in the centre of a home range by the intruding neighbour are more often accompanied by infanticidal attempts than encounters at the edge. Loud calls of neighbours played back from the centre of the home range caused a more vigorous reaction from the resident male than calls from the edge. However, males in food-containing trees did not respond differently to edge playbacks from males in non-food-containing trees. Although males seem to defend resources and not mates, male behaviour may be best explained by defence of infants against infanticide. Female behaviour is best explained by resource defence.

@article{wichPlaybacksLoudCalls2002,
	title = {Playbacks of loud calls to wild thomas langurs ({Primates}; {Presbytis} thomasi): {The} effect of familiarity},
	volume = {139},
	url = {://000175684300006},
	abstract = {A number of studies on birds and mammals have shown that individuals respond differently to neighbour and stranger call playbacks. This response is generally thought to be adaptive, because differentiating calls from neighbours and strangers can prevent the costs of unnecessary contests. In addition, it has recently been suggested that female lions use call recognition to avoid infanticidal males. In this paper we show that Thomas langur (Presbytis thomasi) males react more vigorously towards calls from strange than neighbouring males. It is hypothesised that, although differentiating between calls from different males can be useful to reduce unnecessary contests between the males, discriminating between individual calls is important because it might reduce the risk of infanticide.},
	journal = {Behaviour},
	author = {Wich, S. A. and Assink, P. R. and Becher, F. and Sterck, E. H. M.},
	month = jan,
	year = {2002},
	pages = {79--87},
}

A number of studies on birds and mammals have shown that individuals respond differently to neighbour and stranger call playbacks. This response is generally thought to be adaptive, because differentiating calls from neighbours and strangers can prevent the costs of unnecessary contests. In addition, it has recently been suggested that female lions use call recognition to avoid infanticidal males. In this paper we show that Thomas langur (Presbytis thomasi) males react more vigorously towards calls from strange than neighbouring males. It is hypothesised that, although differentiating between calls from different males can be useful to reduce unnecessary contests between the males, discriminating between individual calls is important because it might reduce the risk of infanticide.

@article{wichMeasuringFruitPatch2002,
	title = {Measuring fruit patch size for three sympatric {Indonesian} primate species},
	volume = {43},
	url = {://000174819400003},
	abstract = {Food availability is one of the basic factors affecting primate density and socioecology, but food availability is difficult to assess. Two different ways to obtain accurate estimates of food availability have been proposed: using phonology data or using the behaviour of animals. Phonology data can be refined by only including trees that are large enough to be used; including (potential) tree species in which by the concerned primate: species forage; or including (fruiting) trees of these species that actually produce fruit. Alternatively, the sizes of the actually visited trees (foraging trees) give an estimate of fruit availability. These measures are compared for three sympatric primate species at the Ketambe Research Station, Sumatra, Indonesia: the Thomas langur, the long-tailed macaque and the orangutan. The sizes of fruiting trees and the foraging trees are larger than the potential trees. The sizes of the potential trees and of the fruiting trees are similar for the three primate species. This, however, is not reflected in the use of trees: the langurs forage on average in trees of similar size to those producing fruit, whereas the macaques and orangutans forage in trees larger than those producing fruit. The use of trees does not necessitate a different cut off point of included dbhs for the three compared primate species. The use of trees of different sizes, however, may be regulated by food competition. This indicates that sympatric primates make different foraging decisions and that behavioural measures of food availability will be less reliable.},
	number = {1},
	journal = {Primates},
	author = {Wich, S. A. and Fredriksson, G. and Sterck, E. H. M.},
	month = jan,
	year = {2002},
	pages = {19--27},
}

Food availability is one of the basic factors affecting primate density and socioecology, but food availability is difficult to assess. Two different ways to obtain accurate estimates of food availability have been proposed: using phonology data or using the behaviour of animals. Phonology data can be refined by only including trees that are large enough to be used; including (potential) tree species in which by the concerned primate: species forage; or including (fruiting) trees of these species that actually produce fruit. Alternatively, the sizes of the actually visited trees (foraging trees) give an estimate of fruit availability. These measures are compared for three sympatric primate species at the Ketambe Research Station, Sumatra, Indonesia: the Thomas langur, the long-tailed macaque and the orangutan. The sizes of fruiting trees and the foraging trees are larger than the potential trees. The sizes of the potential trees and of the fruiting trees are similar for the three primate species. This, however, is not reflected in the use of trees: the langurs forage on average in trees of similar size to those producing fruit, whereas the macaques and orangutans forage in trees larger than those producing fruit. The use of trees does not necessitate a different cut off point of included dbhs for the three compared primate species. The use of trees of different sizes, however, may be regulated by food competition. This indicates that sympatric primates make different foraging decisions and that behavioural measures of food availability will be less reliable.

@article{wichMaleLongdistanceCalls2002,
	title = {Do male "long-distance calls" function in mate defense? {A} comparative study of long-distance calls in primates},
	volume = {52},
	url = {://000179574400006},
	abstract = {Long-distance calls produced by males are common among vertebrate species. Several hypotheses have been proposed to explain features of male long-distance calls and their phylogenetic distribution in primates, but the putative functions of male long-distance calls have yet to be tested comprehensively. We used phylogenetic comparative methods to investigate hypotheses for the function of male long-distance calls. We focused on the mate defense hypothesis, which states that male long-distance calls function in intra-sexual competition for mates, but we also examined factors involving resource defense, mate attraction, and habitat. Phylogenetic reconstruction of male long-distance calls in 158 primate species indicates that the presence of male long-distance calls is the ancestral state. The carrying distance of male long-distance calls is correlated with the size of the home range, which is consistent with the role of male long-distance calls in defending mates, attracting mates, and defending resources. However, measures of male intra-sexual competition were not associated with the evolution of male long-distance calls. Evolutionary transitions were only partly correlated with factors related to mate attraction. Instead, the strongest correlates of male long-distance calls were activity period, body mass, home range, habitat and some measures of resource defense. Our results are consistent with long-distance call production as a costly signal, but detailed study within species is required to assess these costs and the functions of long-distance calls in individual cases. Electronic Supplementary Material is available if you access this article at http://dx.doi.org/10.1007/.},
	number = {6},
	journal = {Behavioral Ecology and Sociobiology},
	author = {Wich, S. A. and Nunn, C. L.},
	month = nov,
	year = {2002},
	pages = {474--484},
}

Long-distance calls produced by males are common among vertebrate species. Several hypotheses have been proposed to explain features of male long-distance calls and their phylogenetic distribution in primates, but the putative functions of male long-distance calls have yet to be tested comprehensively. We used phylogenetic comparative methods to investigate hypotheses for the function of male long-distance calls. We focused on the mate defense hypothesis, which states that male long-distance calls function in intra-sexual competition for mates, but we also examined factors involving resource defense, mate attraction, and habitat. Phylogenetic reconstruction of male long-distance calls in 158 primate species indicates that the presence of male long-distance calls is the ancestral state. The carrying distance of male long-distance calls is correlated with the size of the home range, which is consistent with the role of male long-distance calls in defending mates, attracting mates, and defending resources. However, measures of male intra-sexual competition were not associated with the evolution of male long-distance calls. Evolutionary transitions were only partly correlated with factors related to mate attraction. Instead, the strongest correlates of male long-distance calls were activity period, body mass, home range, habitat and some measures of resource defense. Our results are consistent with long-distance call production as a costly signal, but detailed study within species is required to assess these costs and the functions of long-distance calls in individual cases. Electronic Supplementary Material is available if you access this article at http://dx.doi.org/10.1007/.

@incollection{janmaatTravelLeadershipWild2001,
	address = {Adelaid},
	title = {Travel leadership in wild {Thomas} langurs {Presbytis} thomasi: {Who} wins the conflict?},
	booktitle = {{THE} {18TH} {CONGRESS} {OF} {THE} {INTERNATIONAL} {PRIMATOLOGICAL} {SOCIETY}. {PRIMATES} {IN} {THE} {NEW} {MILLENNIUM}. {ABSTRACTS} {AND} {PROGRAMME}},
	publisher = {IPS},
	author = {Janmaat, K. R. L. and Wich, S. A.},
	year = {2001},
	pages = {504},
}

@article{wichImpactNinoMast2000,
	title = {The impact of {El} {Nino} on mast fruiting in {Sumatra} and elsewhere in {Malesia}},
	volume = {16},
	url = {://000089043300005},
	abstract = {Long-term data on Bower and fruit production of the forest community in two lowland tropical rain forests in north-western Sumatra are presented. The proportion of years with mast fruiting was found to be similar to that found elsewhere in Malesia. However, masting at the two sites, 70 km apart, did not coincide, and showed no correlation with the El Nino-Southern Oscillation phenomenon (ENSO). Comparisons with other sites in Malesia suggest a general waning of ENSO's impact toward western Malesia. Spatial variation at various scales in the timing of masting events was noted in Sumatra and elsewhere. This suggests that additional factors to ENSO play a role in determining forest-level mast fruiting, and we hypothesize that frugivorous animals have the opportunity to track mast fruiting. It is hypothesized that asynchrony between nearby areas in masting increases toward the western edge of Malesia.},
	journal = {Journal of Tropical Ecology},
	author = {Wich, S. A. and Van Schaik, C. P.},
	month = jul,
	year = {2000},
	pages = {563--577},
}

Long-term data on Bower and fruit production of the forest community in two lowland tropical rain forests in north-western Sumatra are presented. The proportion of years with mast fruiting was found to be similar to that found elsewhere in Malesia. However, masting at the two sites, 70 km apart, did not coincide, and showed no correlation with the El Nino-Southern Oscillation phenomenon (ENSO). Comparisons with other sites in Malesia suggest a general waning of ENSO's impact toward western Malesia. Spatial variation at various scales in the timing of masting events was noted in Sumatra and elsewhere. This suggests that additional factors to ENSO play a role in determining forest-level mast fruiting, and we hypothesize that frugivorous animals have the opportunity to track mast fruiting. It is hypothesized that asynchrony between nearby areas in masting increases toward the western edge of Malesia.

@article{wichDeterminantsOrangutanDensity0000,
	title = {Determinants of orang-utan density in the dryland forests of the {Leuser} ecosystem},
	volume = {45},
	journal = {Primates},
	author = {Wich, S.A. and Buij, R. and van Schaik, C.P.},
	year = {0000},
	pages = {177--182},
}