Passive acoustic density estimation of sperm whales in the Tongue of the Ocean, Bahamas

Oceanic odontocetes rely on echolocation to forage on pelagic or benthic prey, but their feeding ecology is difficult to study. We studied sperm whale foraging dives during summer in the north-western Mediterranean, using visual and passive acoustic observations. Clicking and creaking activities were recorded during dives of focal whales, at distances <3000 m using a towed hydrophone and DAT recorder. A total of 52 sperm whales were recorded over at least one full dive cycle. Data were obtained for 156 complete dives in total, including sequences of up to nine consecutive dives. Various dive and environmental variables were entered in multiple linear regression and principal components analysis, as well as estimated mass of whales. Creak rate was 0.80 creak/minute on average, with moderate variance. Bigger whales tended to dive longer at greater depths (as suggested by ascent durations), and emitted more creaks during a dive: 20.2 creaks/dive on average for individuals <24 tons, compared to 25.6 creaks/dive for animals >24 tons of estimated mass. For individual whales, creak rates did not vary significantly with size (range 0.78–0.80 creak/minute), but decreased with time of the day, and increased for shorter foraging phases. For different dives, higher creak rates were also observed earlier in the day, and linked to shorter foraging phases and surface durations. Although the exact significance of creak emissions (i.e. foraging attempt or prey capture) is not precisely determined, creak rates may be reliably used to quantify sperm whale foraging when single animal dives can be followed acoustically.

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Density estimation of leopard seals using a single stationary passive acoustic sensor.

The Journal of the Acoustical Society of America ◽

10.1121/1.3384227 ◽

2010 ◽

Vol 127 (3) ◽

pp. 1825-1825

Author(s):

Holger Klinck ◽

Nadine Constantinou ◽

David K. Mellinger ◽

Tracey Rogers

Keyword(s):

Density Estimation ◽

Acoustic Sensor ◽

Passive Acoustic

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Passive acoustic monitoring of sperm whales during and after the Deepwater Horizon oil spill

The Journal of the Acoustical Society of America ◽

10.1121/1.3655135 ◽

2011 ◽

Vol 130 (4) ◽

pp. 2537-2537

Author(s):

Karlina Merkens ◽

Mark A. McDonald ◽

Simone Baumann-Pickering ◽

Kaitlin Frasier ◽

Sean M. Wiggins ◽

...

Keyword(s):

Oil Spill ◽

Deepwater Horizon ◽

Acoustic Monitoring ◽

Sperm Whales ◽

Passive Acoustic Monitoring ◽

Deepwater Horizon Oil Spill ◽

Passive Acoustic

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Temporal patterns in detections of sperm whales (Physeter macrocephalus) in the North Pacific Ocean based on long-term passive acoustic monitoring

The Journal of the Acoustical Society of America ◽

10.1121/1.4899783 ◽

2014 ◽

Vol 136 (4) ◽

pp. 2153-2153

Author(s):

Karlina Merkens ◽

Anne Simonis ◽

Erin Oleson

Keyword(s):

Pacific Ocean ◽

North Pacific ◽

North Pacific Ocean ◽

Physeter Macrocephalus ◽

Sperm Whales ◽

Passive Acoustic Monitoring ◽

The North ◽

Passive Acoustic ◽

The North Pacific

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From clicks to counts: Applying line-transect methods to passive acoustic monitoring of sperm whales in the Gulf of Alaska

The Journal of the Acoustical Society of America ◽

10.1121/1.4900107 ◽

2014 ◽

Vol 136 (4) ◽

pp. 2246-2246

Author(s):

Tina M. Yack ◽

Thomas F. Norris ◽

Elizabeth Ferguson ◽

Brenda K. Rone ◽

Alexandre N. Zerbini

Keyword(s):

Gulf Of Alaska ◽

Acoustic Monitoring ◽

Line Transect ◽

Sperm Whales ◽

Passive Acoustic Monitoring ◽

Passive Acoustic

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Analysis of bearings of vocalizing marine mammals in relation to passive acoustic density estimation

The Journal of the Acoustical Society of America ◽

10.1121/1.4933686 ◽

2015 ◽

Vol 138 (3) ◽

pp. 1792-1792

Author(s):

Julia A. Vernon ◽

Jennifer L. Miksis-Olds ◽

Danielle Harris

Keyword(s):

Density Estimation ◽

Marine Mammals ◽

Passive Acoustic

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Cues, creaks, and decoys: using passive acoustic monitoring as a tool for studying sperm whale depredation

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv024 ◽

2015 ◽

Vol 72 (5) ◽

pp. 1621-1636 ◽

Cited By ~ 13

Author(s):

Aaron Thode ◽

Delphine Mathias ◽

Janice Straley ◽

Victoria O'Connell ◽

Linda Behnken ◽

...

Keyword(s):

Low Frequency ◽

Field Tests ◽

Sperm Whale ◽

Acoustic Monitoring ◽

Sperm Whales ◽

Passive Acoustic Monitoring ◽

Long Distance ◽

Fishing Activity ◽

Fishing Vessels ◽

Passive Acoustic

Abstract Since 2003, a collaborative effort (SEASWAP) between fishers, scientists, and managers has researched how Alaskan sperm whales locate demersal longline fishing activity and then depredate sablefish from gear. Sperm whales constantly produce relatively low-frequency biosonar signals whenever foraging; therefore, over the past decade, passive acoustic monitoring (PAM) has become a basic tool, used for both measuring depredation activity and accelerating field tests of potential depredation countermeasures. This paper reviews and summarizes past published PAM research on SEASWAP, and then provides a detailed example of how PAM methods are currently being used to test countermeasures. The review covers two major research thrusts: (i) identifying acoustic outputs of fishing vessels that provide long-distance “cues” that attract whales to fishing activity; and (ii) validating whether distinctive “creak” sounds can be used to quantify and measure depredation rates, using both bioacoustic tags and statistical comparisons between visual and acoustic depredation estimates during federal sablefish surveys. The latter part of the paper then provides an example of how PAM is being used to study a particular potential countermeasure: an “acoustic decoy” which transmits fishing vessel acoustic cues to attract animals away from true fishing activity. The results of an initial 2011 field trial are presented to show how PAM was used to design the decoy signals and monitor the efficacy of the deployment. The ability of PAM to detect both whale presence and depredation behaviour has reduced the need to deploy researchers or other specialists on fishing cruises. Instead, volunteer fishers can deploy “user-friendly” acoustic recorders on their gear, greatly facilitating the testing of various deterrents, and providing the industry and regulators a convenient and unobtrusive tool for monitoring both the scale and long-term spread of this behaviour across the Alaskan fishery.

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