Publications (41) View all
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Article: Description of sounds recorded from Longman's beaked whale, Indopacetus pacificus.
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ABSTRACT: Sounds from Longman's beaked whale, Indopacetus pacificus, were recorded during shipboard surveys of cetaceans surrounding the Hawaiian Islands archipelago; this represents the first known recording of this species. Sounds included echolocation clicks and burst pulses. Echolocation clicks were grouped into three categories, a 15 kHz click (n = 106), a 25 kHz click (n = 136), and a 25 kHz pulse with a frequency-modulated upsweep (n = 70). The 15 and 25 kHz clicks were relatively short (181 and 144 ms, respectively); the longer 25 kHz upswept pulse was 288 ms. Burst pulses were long (0.5 s) click trains with approximately 240 clicks/s.The Journal of the Acoustical Society of America 11/2011; 130(5):EL339-44. · 1.55 Impact Factor -
Article: Humpback whale abundance in the North Pacific estimated by photographic capture‐recapture with bias correction from simulation studies
Marine Mammal Science 11/2011; 27:793-818. · 1.61 Impact Factor -
Article: Acoustics as a tool in sub-species and population identification for endangered fin whales, Balaenoptera physalus.
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ABSTRACT: Identification of "stocks" (sub-species and independent populations) is important for understanding and mitigating potential sources of human-caused mortality. This is especially critical for endangered and protected species, such as the large whales. Stock identification for whales has typically been based on ecology, life history, morphology, and genetics. However, for many species, acoustic differences in whale call types may indicate population or sub-species structure. The potential role of acoustics in identifying species and sub-species has been identified in numerous publications; however, this role has yet to be realized for large whales. In an effort to include acoustic data in this process, we are contributing to current efforts to update the status of endangered fin whales, Balaenoptera physalus, in the North Pacific. An analysis of North Pacific fin whale populations based on identification of "song" provides hypotheses that can be tested with genetics. Strengths and limitations of acoustic methods will be presented, as will the potential for collaboration on the scale of ocean basins.The Journal of the Acoustical Society of America 10/2011; 130(4):2421. · 1.55 Impact Factor -
Article: Statistical design for acoustic monitoring to detect declines of endangered species and prevent extinction.
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ABSTRACT: As populations become smaller and more endangered, the ability to monitor trends in their abundance also decreases. For vocal species, passive acoustic monitoring can provide a powerful, cost-effective method of monitoring relative abundance. However, the monitoring effort should be based on a statistical design that can detect population declines in time to prevent extinction. This is illustrated with an example of the vaquita (Phocoena sinus) an endangered porpoise in the northern Gulf of California, Mexico. A pilot project showed that porpoise detectors (C-PODs) recorded echo-location clicks from approximately one group of porpoises every two days. Based on this, we estimate that 5000 days of C-POD monitoring per year would be needed to obtain a measure of relative vaquita abundance with a coefficient of variation (CV) of 3%. A power analysis shows that five years of monitoring with this CV would give a high probability of detecting a 5% annual increase or decrease in population size. Visual sighting methods could not detect such small changes with any conceivable level of survey effort. This kind of innovative monitoring is a critical tool in the continuing evaluation of conservation measures.The Journal of the Acoustical Society of America 10/2011; 130(4):2420. · 1.55 Impact Factor -
Article: The world's smallest whale population?
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ABSTRACT: The North Pacific right whale (Eubalaena japonica) was heavily exploited by both nineteenth century whaling and recent (1960s) illegal Soviet catches. Today, the species remains extremely rare especially in the eastern North Pacific. Here, we use photographic and genotype data to calculate the first mark-recapture estimates of abundance for right whales in the Bering Sea and Aleutian Islands. The estimates were very similar: photographic = 31 (95% CL 23-54), genotyping = 28 (95% CL 24-42). We also estimated the population contains eight females (95% CL 7-18) and 20 males (95% CL 17-37). Although these estimates may relate to a Bering Sea subpopulation, other data suggest that the total eastern North Pacific population is unlikely to be much larger. Its precarious status today-the world's smallest whale population for which an abundance estimate exists-is a direct consequence of uncontrolled and illegal whaling, and highlights the past failure of international management to prevent such abuses.Biology letters 02/2011; 7(1):83-5. · 3.76 Impact Factor
