ACCURACY ANALYSES OF PASSIVE TRACKING OF SEVERAL CLICKING SPERM WHALES - A Case of Complex Sources Binding

2008 ◽  
Keyword(s):  
Sperm Whales ◽  
Passive Tracking

Passive tracking of multiple diving sperm whales using single hydrophones at two mobile locations

2004 ◽  
Vol 115 (5) ◽  
pp. 2518-2519 ◽  
Author(s):  
Rajendar Bahl ◽  
Takeshi Nakatani ◽  
Tamaki Ura ◽  
Junichi Kojima ◽  
Tetsuo Fukuchi ◽  
...  
Keyword(s):  
Sperm Whales ◽  
Passive Tracking

Notes on the Right and Sperm Whales

1873 ◽  
Vol 7 (1) ◽  
pp. 1-4 ◽  
Author(s):  
N. S. Shaler
Keyword(s):  
Sperm Whales ◽  
The Right

First record of Norwegian killer whales attacking and feeding on a harbour porpoise

2015 ◽  
Vol 8 ◽  
Author(s):  
A. Mel Cosentino
Keyword(s):  
North Atlantic ◽  
Marine Mammals ◽  
First Record ◽  
Harbour Porpoise ◽  
Sperm Whales ◽  
Killer Whales ◽  
Strait Of Gibraltar ◽  
Cetacean Species ◽  
The North ◽  
Northern Bottlenose Whales

Orcinus orcais a cosmopolitan species and the most widely distributed marine mammal. Its diet includes over 140 species of fish, cephalopods, sea birds and marine mammals. However, many populations are specialised on certain specific prey items. Three genetically distinct populations have been described in the North Atlantic. Population A (that includes the Icelandic and Norwegian sub-populations) is believed to be piscivorous, as is population C, which includes fish-eating killer whales from the Strait of Gibraltar. In contrast, population B feeds on both fish and marine mammals. Norwegian killer whales follow the Norwegian spring spawning herring stock. The only description in the literature of Norwegian killer whales feeding on another cetacean species is a predation event on northern bottlenose whales in 1968. Daily land-based surveys targeting sperm whales were conducted from the Andenes lighthouse using BigEyes®binoculars (25×, 80 mm). The location of animals at sea was approximated through the use of an internal reticule system and a graduated wheel. On 24 June 2012 at 3:12 am, an opportunistic sighting of 11 killer whales was made off Andenes harbour. The whales hunted and fed on a harbour porpoise. Despite these species having overlapping distributions in Norwegian waters, this is the first predatory event reported in the literature.

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.

scholarly journals Cetacean strandings along the Pacific and Caribbean coasts of Nicaragua from 2014 to 2021

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Joëlle De Weerdt ◽  
Eric Angel Ramos ◽  
Etienne Pouplard ◽  
Marc Kochzius ◽  
Phillip Clapham
Keyword(s):  
Marine Mammals ◽  
Sperm Whale ◽  
Distribution Patterns ◽  
Sperm Whales ◽  
The Pacific ◽  
Toothed Whale ◽  
Beaked Whales ◽  
Causes Of Mortality ◽  
Cuvier’S Beaked Whale ◽  
Stenella Attenuata

AbstractDocumenting marine mammal strandings provides important information needed to understand the occurrence and distribution patterns of species. Here, we report on strandings of cetaceans on the Pacific (n = 11) and Caribbean (n = 2) coasts of Nicaragua, documented opportunistically from 2014 to 2021. Strandings included three species of baleen whale (blue whale Balaenoptera musculus, Bryde’s whale Balaenoptera edeni, humpback whale Megaptera novaeangliae) and five species of toothed whale (dwarf sperm whale Kogia sima, Guiana dolphin Sotalia guianensis, pantropical spotted dolphin Stenella attenuata, spinner dolphin Stenella longirostris, Cuvier’s beaked whale Ziphius cavirostris). These are the first published accounts of blue whales, Bryde’s whales, dwarf sperm whales, and Cuvier’s beaked whales in Nicaraguan waters. Limited resources and the advanced decomposition of animals prevented necropsies in most cases, the identification of the causes of mortality in all cases, and the species identification of two dolphins. Information derived from these stranding events offers new insights into the occurrence of marine mammals on the Pacific and Caribbean coasts of Nicaragua and Central America.

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