Automated detection of sperm whales (Physeter macrocephalus) creaks and association with depredation events.

2010 ◽  
Vol 127 (3) ◽  
pp. 2005-2005
Author(s):  
Delphine Mathias ◽  
Aaron Thode ◽  
Jan Straley ◽  
John Calambokidis ◽  
Gregory S. Schorr ◽  
...  
Keyword(s):  
Automated Detection ◽  
Physeter Macrocephalus ◽  
Sperm Whales

scholarly journals Severity Scoring of Behavioral Responses of Sperm Whales (Physeter macrocephalus) to Novel Continuous versus Conventional Pulsed Active Sonar

2021 ◽  
Vol 9 (4) ◽  
pp. 444
Author(s):  
Charlotte Curé ◽  
Saana Isojunno ◽  
Marije L. Siemensma ◽  
Paul J. Wensveen ◽  
Célia Buisson ◽  
...  
Keyword(s):  
Behavioral Responses ◽  
Physeter Macrocephalus ◽  
Vital Rates ◽  
Sperm Whales ◽  
Experimental Conditions ◽  
Active Sonar ◽  
Lower Amplitude ◽  
Pilot Whales ◽  
New Generation ◽  
Free Ranging

Controlled exposure experiments (CEEs) have demonstrated that naval pulsed active sonar (PAS) can induce costly behavioral responses in cetaceans similar to antipredator responses. New generation continuous active sonars (CAS) emit lower amplitude levels but more continuous signals. We conducted CEEs with PAS, CAS and no-sonar control on free-ranging sperm whales in Norway. Two panels blind to experimental conditions concurrently inspected acoustic-and-movement-tag data and visual observations of tagged whales and used an established severity scale (0–9) to assign scores to putative responses. Only half of the exposures elicited a response, indicating overall low responsiveness in sperm whales. Responding whales (10 of 12) showed more, and more severe responses to sonar compared to no-sonar. Moreover, the probability of response increased when whales were previously exposed to presence of predatory and/or competing killer or long-finned pilot whales. Various behavioral change types occurred over a broad range of severities (1–6) during CAS and PAS. When combining all behavioral types, the proportion of responses to CAS was significantly higher than no-sonar but not different from PAS. Responses potentially impacting vital rates i.e., with severity ≥4, were initiated at received cumulative sound exposure levels (dB re 1 μPa2 s) of 137–177 during CAS and 143–181 during PAS.

Behaviour and Vocalizations of Two Single Sperm Whales, Physeter macrocephalus, Off Nova Scotia

1988 ◽  
Vol 45 (10) ◽  
pp. 1736-1743 ◽  
Author(s):  
Julia Mullins ◽  
Hal Whitehead ◽  
Linda S. Weilgart
Keyword(s):  
Nova Scotia ◽  
Sound Production ◽  
Ocean Floor ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Scotian Shelf ◽  
Male Sperm

During June 1986, two male sperm whales, Physeter macrocephalus, on the Scotian Shelf were tracked by listening for their clicks with a directional hydrophone for periods of 12.5 and 7 h, respectively. Each whale travelled along the edge of the shelf at about 2 kn (3.6 km/h), and one whale, on two occasions at least, dived to the ocean floor. After about 30 min underwater, the whales spent approximately 9 min at the surface breathing. When the whales were visible at the surface, they were silent, except on one occasion when "slow clicking" (mean interclick interval of 4.6 s) was heard from Whale 2. While underwater, most of the sound production consisted of "usual clicks" (mean interclick interval 0.96 and 0.69 s for the two whales) interrupted by frequent short silences (mean durations 21.06 and 27.82 s) and occasional "creaks" (with interclick intervals less than 0.2 s) and "slow clicks." No "codas" (stereotyped patterns of clicks) were heard from these two single whales. These results are consistent with the hypotheses that "usual clicks" and "creaks" are used for echolocation and "codas" for communication.

Variations in the feeding success and behaviour of Galápagos sperm whales (Physeter macrocephalus) as they relate to oceanographie conditions

1993 ◽  
Vol 71 (10) ◽  
pp. 1991-1996 ◽  
Author(s):  
Sean C. Smith ◽  
Hal Whitehead
Keyword(s):  
Surface Temperature ◽  
Significant Variation ◽  
Foraging Behaviour ◽  
Geographic Area ◽  
Sea Surface ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Feeding Success ◽  
Galapagos Archipelago ◽  
Oceanographic Conditions

The feeding success of sperm whales off the Galápagos Islands, Ecuador, was examined over 5 study years; 1985, 1987, 1988, 1989, and 1991. A total of 160 days were spent following sperm whales at sea. The defaecation rates of sperm whales were used as an indication of feeding success. The recorded acoustic click rates of sperm whales were used as an indication of aggregative and foraging behaviour. Significant variation in feeding success occurred temporally over periods of days, months, and years. Feeding success also varied spatially with geographic area. Feeding success was inversely related to sea surface temperature (SST). The foraging and associative behaviour of sperm whales also varied with feeding success, SST, and by year. Variations in the feeding success and behaviour of Galápagos sperm whales can likely be attributed to changing oceanographic conditions in the waters surrounding the Galápagos archipelago.

scholarly journals Estimated Abundances of Cetacean Species in the Northeast Atlantic from Norwegian Shipboard Surveys Conducted in 2014–2018

2020 ◽  
Vol 11 ◽  
Author(s):  
Deanna Leonard ◽  
Nils Øien
Keyword(s):  
Barents Sea ◽  
Humpback Whales ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Target Species ◽  
Independent Observer ◽  
Southern Boundary ◽  
Norwegian Sea ◽  
Northeast Atlantic ◽  
Fin Whales

A ship-based mosaic survey of Northeast Atlantic cetaceans was conducted over a 5-year period between 2014–2018. The area surveyed extends from the North Sea in the south (southern boundary at 53oN), to the ice edge of the Barents Sea and the Greenland Sea. Survey vessels were equipped with 2 independent observer platforms that detected whales in passing mode and applied tracking procedures for the target species, common minke whales (Balaenoptera acutorostrata acutorostrata). Here we present abundance estimates for all non-target species for which there were sufficient sightings. We estimate the abundance of fin whales (Balaenoptera physalus) to be 11,387 (CV=0.17, 95% CI: 8,072–16,063), of humpback whales (Megaptera novaeangliae) to be 10,708 (CV=0.38, 95% CI: 4,906–23,370), of sperm whales (Physeter macrocephalus) to be 5,704 (CV=0.26, 95% CI: 3,374–9,643), of killer whales (Orcinus orca) to be 15,056 (CV=0.29, 95% CI: 8,423–26,914), of harbour porpoises (Phocoena phocoena) to be 255,929 (CV=0.20, 95% CI: 172,742–379,175), dolphins of genus Lagenorhynchus to be 192,767 (CV=0.25, 95% CI: 114,033–325,863), and finally of northern bottlenose whales (Hyperoodon ampullatus) to be 7,800 (CV=0.28, 95% CI: 4,373–13,913). Additionally, our survey effort in the Norwegian Sea in 2015 contributed to the 6th North Atlantic Sightings Survey (NASS) and the survey was extended into the waters north and east of Iceland around Jan Mayen island. This NASS extension, along with our Norwegian Sea survey in 2015, was used to estimate the abundance of fin whales, humpback whales, and sperm whales. All estimates presented used mark-recapture distance sampling techniques and were thus corrected for perception bias. Our estimates do not account for additional variance due to distributional shifts between years or biases due to availability or responsive movement.

scholarly journals Long-term associations among male sperm whales (Physeter macrocephalus)

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244204
Author(s):  
Hayao Kobayashi ◽  
Hal Whitehead ◽  
Masao Amano
Keyword(s):  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Association Rate ◽  
Photo Identification ◽  
Male Sperm ◽  
The Social ◽  
Pelagic Habitat ◽  
Best Fitting ◽  
Social Associations

Little is known about the social structure of male sperm whales (Physeter macrocephalus) after they leave their natal units. While previous studies found no evidence for preferred associations among males, the observation of mass-strandings consisting exclusively of males, suggest that they have strong social bonds. To investigate the social associations among male sperm whales, we used half weight index of association, permutation tests and standardized lagged association rate models on a large photo-identification database collected between 2006 and 2017 in Nemuro Strait, Japan. Our results suggest that while male sperm whales are not as social as females, they do form long term associations, have preferred companionship, and forage in social proximity to each other. The best-fitting model to the standardized lagged association rate showed that associations among males last for at least 2.7 years and as most males leave the area after 2 years, associations may last for longer. Twenty dyads were observed associating over more than 2 years, for a maximum 5 years. One dyad was observed associating on 19 different days and clustered on 7 different days. Male associations may function to enhance foraging or to fend off predators. Such relationships seem to be adapted to a pelagic habitat with uncertain resource availability and predation pressure.

Occurrence of anthropozoonotic parasitic infections and faecal microbes in free-ranging sperm whales (Physeter macrocephalus) from the Mediterranean Sea

2018 ◽  
Vol 117 (8) ◽  
pp. 2531-2541 ◽  
Author(s):  
Carlos Hermosilla ◽  
J. Hirzmann ◽  
L. M. R. Silva ◽  
J. M. Brotons ◽  
M. Cerdà ◽  
...  
Keyword(s):  
Mediterranean Sea ◽  
Parasitic Infections ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
The Mediterranean ◽  
Free Ranging
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