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| De Ruiter, Stacy; Hansen, Michael; Koopman, Heather N.; Westgate, Andrew J.; Tyack, Peter L.; Madsen, Peter T.. |
| Estimating the range at which harbor porpoises can detect prey items and environmental objects is integral to understanding their biosonar. Understanding the ranges at which they can use echolocation to detect and avoid obstacles is particularly important for strategies to reduce bycatch. Transmission loss (TL) during acoustic propagation is an important determinant of those detection ranges, and it also influences animal detection functions used in passive acoustic monitoring. However, common assumptions regarding TL have rarely been tested. Here, TL of synthetic porpoise clicks was measured in porpoise habitats in Canada and Denmark, and field data were compared with spherical spreading law and ray-trace (Bellhop) model predictions. Both models matched... |
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| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/2010/publication-7395.pdf |
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| De Ruiter, Stacy; Boyd, Ian L.; Claridge, Diane E.; Clark, Christopher W.; Gagnon, Chuck; Southall, Brandon L.; Tyack, Peter L.. |
| In 2007 and 2008, controlled exposure experiments were performed in the Bahamas to study behavioral responses to simulated mid-frequency active sonar (MFA) by three groups of odontocetes: false killer whales, Pseudorca crassidens; short-finned pilot whales, Globicephala macrorhynchus; and melon-headed whales, Peponocephala electra. An individual in each group was tagged with a Dtag to record acoustic and movement data. During exposures, some individuals produced whistles that seemed similar to the experimental MFA stimulus. Statistical tests were thus applied to investigate whistle-MFA similarity and the relationship between whistle production rate and MFA reception time. For the false killer whale group, overall whistle rate and production rate of the... |
| Tipo: Text |
Palavras-chave: Noise; Sonar; Mid-frequency sonar; Whistle; Behavioral effects; Sound production; Pseudorca crassidens; Globicephala macrorhynchus; Peponocephala electra; False killer whale; Pilot whale; Melon-headed whale. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00138/24974/23185.pdf |
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| De Ruiter, Stacy; Bahr, Alexander; Blanchet, Marie-anne; Hansen, Sabina Fobian; Kristensen, Jakob Hojer; Madsen, Peter T.; Tyack, Peter L.; Wahlberg, Magnus. |
| Porpoise echolocation has been studied previously, mainly in target detection experiments using stationed animals and steel sphere targets, but little is known about the acoustic behaviour of free-swimming porpoises echolocating for prey. Here, we used small onboard sound and orientation recording tags to study the echolocation behaviour of free-swimming trained porpoises as they caught dead, freely drifting fish. We analysed porpoise echolocation behaviour leading up to and following prey capture events, including variability in echolocation in response to vision restriction, prey species, and individual porpoise tested. The porpoises produced echolocation clicks as they searched for the fish, followed by fast-repetition-rate clicks (echolocation buzzes)... |
| Tipo: Text |
Palavras-chave: Echolocation; Porpoise; Foraging; Buzz; Biosonar; Phocoena. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/00000/11111/8969.pdf |
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