{"_id":"ALeZLMnRJZqhvkfXt","bibbaseid":"johnson-tyack-measuringthebehaviorandresponsetosoundofbeakedwhalesusingrecordingtags","authorIDs":[],"author_short":["Johnson, M.","Tyack, P."],"bibdata":{"bibtype":"unpublished","type":"unpublished","author":[{"firstnames":["Mark"],"propositions":[],"lastnames":["Johnson"],"suffixes":[]},{"firstnames":["Peter"],"propositions":[],"lastnames":["Tyack"],"suffixes":[]}],"title":"Measuring the behavior and response to sound of beaked whales using recording tags","comment":"Results from the study are directed at two strategies to reduce beaked whale mortality: first, with a specification of how and when these animals vocalize, it may be possible to develop systems for passive acoustic detection of beaked whales. Since beaked whales are so difficult to sight, acoustic detection is a critical method to monitor for the presence of these sensitive species before and during sonar trials. The second, longer-term strategy is to determine what factors heighten the risk of stranding and to identify opportunities to minimize these. If risk assessments continue to highlight an urgent need to define safe exposure limits for beaked whales, we propose to plan a pilot study on the behavioral responses of beaked whales to low levels of sonar-like sounds. This is the description of a project, with many interesting facts! Although the NOPP project only began in May 2004, we have already made a number of significant advances. With leverage from SERDP and U.S. Navy (N45) funding, we performed lengthy field seasons in our study sites in Italy and the Canary Islands. We have now placed tags on 7 Cuvier's and 3 Blainville's beaked whales. Our data set contains 97 hours of on-animal recording including 44 deep dives and a remarkable 9 hour set in which two Cuvier's beaked whales were tagged contemporaneously in the same group. Three whales (2 Cuvier's and 1 Blainville's) were tagged with high sampling-rate (192kHz) stereo DTAGs, developed this year, providing full-bandwidth recordings of the two species. The double tagging of Cuvier's beaked whales also provided an opportunity to estimate the source level and beamwidth of the click sounds. With this, and the movement information recorded by the tags, we can begin estimating the practicality of passive acoustic detection of these species as a mitigation measure. Several key results have already been obtained in the first year of the project. Using data from the new high-sampling rate tag, we have characterized the vocalizations of Cuvier's and Blainville's beaked whales over their full frequency band. These vocalizations consist of two distinct types of clicks which we refer to as regular and buzz clicks. Both click sounds occur at the base of deep foraging dives as shown in Fig. 1. Regular clicks occur at relatively stable intervals of 0.2 to 0.4s throughout the base of the dive while buzz clicks occur in occasional short bursts with inter-click-intervals of about 5ms. Echoes from approaching targets in the water, recorded by the tags, confirm an echolocation function of both click types and represent the first time that echoes from prey have been recorded on a marine mammal. Based on our findings with sperm whales [Miller 2004], we associate buzz clicks with the terminal phase of a capture sequence. Recordings of buzzes with echoes from prey, made by the tag, provide an unprecedented opportunity to investigate prey selection and capture, and to estimate foraging efficiency [Madsen 2005]. Regular clicks from both beaked whale species have a long duration (200µs) and a distinctive frequency-modulated sweep characteristic, making them unique amongst the odontocetes studied to date. This kind of click may be tailored to discriminate targets in a highly cluttered acoustic environment such as we have observed in the tag recordings. In contrast, the buzz click is of short duration (about 60µs) and is broadband without obvious modulation. The ability to produce two distinct click types has not been described for other odontocetes and may represent a specialization for deep-water foraging. These results have relevance in understanding the habitat selection of beaked whales and in designing passive acoustic monitoring systems for these species. In particular, the distinctive regular clicks may hold the key to discriminating beaked whale sounds from those of ubiquitous species such as dolphin that appear to be less sensitive to sonars. We have submitted a paper describing the broadband clicks of Cuvier's beaked whale [Zimmer, subm.] and are currently preparing a paper on those of Blainville's beaked whale. COOL POINT I HAD NOT SEEN BEFORE: Beaked whales are most often observed in small groups at the surface and are seen to dive synchronously. The use of a stereo acoustic recording tag this year has provided an opportunity to study the behavior of the group during foraging dives. Regular and buzz clicks from untagged whales in the group are frequently heard in the stereo tag recording and the sounds from individuals can be distinguished by their angle-of-arrival. We have been able to count the number of individuals present during a foraging dive and compare it to surface observations of the same group. In each case, most orall of the whales in the group are present in the deep dive, including juveniles. This suggests that dive duration may be determined by the least-capable (e.g., smallest) animal in the group, an interesting counterpoint to the traditional optimal foraging paradigm. If, as is likely, vocalizations mediate this cohesion, then there is a risk that anthropogenic sound such as from sonars may disrupt group communication and thus behavior.","file":"Johnson&Tyack.pdf:Johnson&Tyack.pdf:PDF","owner":"Tiago","subdatabase":"postdoc, beaked","timestamp":"2007.08.13","bibtex":"@Unpublished{Johnson,\r\n author = {Mark Johnson and Peter Tyack},\r\n title = {Measuring the behavior and response to sound of beaked whales using recording tags},\r\n comment = {Results from the study are directed at two strategies to reduce beaked\r\n\twhale mortality: first, with a specification of how and when these\r\n\tanimals vocalize, it may be possible to develop systems for passive\r\n\tacoustic detection of beaked whales. Since beaked whales are so difficult\r\n\tto sight, acoustic detection is a critical method to monitor for\r\n\tthe presence of these sensitive species before and during sonar trials.\r\n\tThe second, longer-term strategy is to determine what factors heighten\r\n\tthe risk of stranding and to identify opportunities to minimize these.\r\n\tIf risk assessments continue to highlight an urgent need to define\r\n\tsafe exposure limits for beaked whales, we propose to plan a pilot\r\n\tstudy on the behavioral responses of beaked whales to low levels\r\n\tof sonar-like sounds.\r\n\t\r\n\t\r\n\tThis is the description of a project, with many interesting facts!\r\n\t\r\n\t\r\n\tAlthough the NOPP project only began in May 2004, we have already\r\n\tmade a number of significant advances. With leverage from SERDP and\r\n\tU.S. Navy (N45) funding, we performed lengthy field seasons in our\r\n\tstudy sites in Italy and the Canary Islands. We have now placed tags\r\n\ton 7 Cuvier's and 3 Blainville's beaked whales. Our data set contains\r\n\t97 hours of on-animal recording including 44 deep dives and a remarkable\r\n\t9 hour set in which two Cuvier's beaked whales were tagged contemporaneously\r\n\tin the same group. Three whales (2 Cuvier's and 1 Blainville's) were\r\n\ttagged with high sampling-rate (192kHz) stereo DTAGs, developed this\r\n\tyear, providing full-bandwidth recordings of the two species. The\r\n\tdouble tagging of Cuvier's beaked whales also provided an opportunity\r\n\tto estimate the source level and beamwidth of the click sounds. With\r\n\tthis, and the movement information recorded by the tags, we can begin\r\n\testimating the practicality of passive acoustic detection of these\r\n\tspecies as a mitigation measure.\r\n\t\r\n\t\r\n\tSeveral key results have already been obtained in the first year of\r\n\tthe project. Using data from the new high-sampling rate tag, we have\r\n\tcharacterized the vocalizations of Cuvier's and Blainville's beaked\r\n\twhales over their full frequency band. These vocalizations consist\r\n\tof two distinct types of clicks which we refer to as regular and\r\n\tbuzz clicks. Both click sounds occur at the base of deep foraging\r\n\tdives as shown in Fig. 1. Regular clicks occur at relatively stable\r\n\tintervals of 0.2 to 0.4s throughout the base of the dive while buzz\r\n\tclicks occur in occasional short bursts with inter-click-intervals\r\n\tof about 5ms. Echoes from approaching targets in the water, recorded\r\n\tby the tags, confirm an echolocation function of both click types\r\n\tand represent the first time that echoes from prey have been recorded\r\n\ton a marine mammal. Based on our findings with sperm whales [Miller\r\n\t2004], we associate buzz clicks with the terminal phase of a capture\r\n\tsequence. Recordings of buzzes with echoes from prey, made by the\r\n\ttag, provide an unprecedented opportunity to investigate prey selection\r\n\tand capture, and to estimate foraging efficiency [Madsen 2005]. Regular\r\n\tclicks from both beaked whale species have a long duration (200µs)\r\n\tand a distinctive frequency-modulated sweep characteristic, making\r\n\tthem unique amongst the odontocetes studied to date. This kind of\r\n\tclick may be tailored to discriminate targets in a highly cluttered\r\n\tacoustic environment such as we have observed in the tag recordings.\r\n\tIn contrast, the buzz click is of short duration (about 60µs) and\r\n\tis broadband without obvious modulation. The ability to produce two\r\n\tdistinct click types has not been described for other odontocetes\r\n\tand may represent a specialization for deep-water foraging. These\r\n\tresults have relevance in understanding the habitat selection of\r\n\tbeaked whales and in designing passive acoustic monitoring systems\r\n\tfor these species. In particular, the distinctive regular clicks\r\n\tmay hold the key to discriminating beaked whale sounds from those\r\n\tof ubiquitous species such as dolphin that appear to be less sensitive\r\n\tto sonars. We have submitted a paper describing the broadband clicks\r\n\tof Cuvier's beaked whale [Zimmer, subm.] and are currently preparing\r\n\ta paper on those of Blainville's beaked whale.\r\n\t\r\n\t\r\n\tCOOL POINT I HAD NOT SEEN BEFORE: Beaked whales are most often observed\r\n\tin small groups at the surface and are seen to dive synchronously.\r\n\tThe use of a stereo acoustic recording tag this year has provided\r\n\tan opportunity to study the behavior of the group during foraging\r\n\tdives. Regular and buzz clicks from untagged whales in the group\r\n\tare frequently heard in the stereo tag recording and the sounds from\r\n\tindividuals can be distinguished by their angle-of-arrival. We have\r\n\tbeen able to count the number of individuals present during a foraging\r\n\tdive and compare it to surface observations of the same group. In\r\n\teach case, most orall of the whales in the group are present in the\r\n\tdeep dive, including juveniles. This suggests that dive duration\r\n\tmay be determined by the least-capable (e.g., smallest) animal in\r\n\tthe group, an interesting counterpoint to the traditional optimal\r\n\tforaging paradigm. If, as is likely, vocalizations mediate this cohesion,\r\n\tthen there is a risk that anthropogenic sound such as from sonars\r\n\tmay disrupt group communication and thus behavior.},\r\n file = {Johnson&Tyack.pdf:Johnson&Tyack.pdf:PDF},\r\n owner = {Tiago},\r\n subdatabase = {postdoc, beaked},\r\n timestamp = {2007.08.13},\r\n}\r\n\r\n","author_short":["Johnson, M.","Tyack, P."],"key":"Johnson","id":"Johnson","bibbaseid":"johnson-tyack-measuringthebehaviorandresponsetosoundofbeakedwhalesusingrecordingtags","role":"author","urls":{},"downloads":0,"html":""},"bibtype":"unpublished","biburl":"http://distancelive.xyz/MainBibFile.bib","creationDate":"2020-06-16T14:23:34.563Z","downloads":0,"keywords":[],"search_terms":["measuring","behavior","response","sound","beaked","whales","using","recording","tags","johnson","tyack"],"title":"Measuring the behavior and response to sound of beaked whales using recording tags","year":null,"dataSources":["RjvoQBP8rG4o3b4Wi"]}