cetacean

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Related to Cetaceans: whale, Sirenia, sperm whale, order Cetacea, Mammals

cetacean

or

whale

any aquatic EUTHERIAN mammal of the order Cetacea, comprising the porpoises, dolphins and whales.

Cetaceans are completely aquatic, have lost their hind limbs during evolution and have fin-like forelimbs, often a dorsal fin and, in marked comparison with fishes, a blowhole and transverse tail fin. The young are large at birth and suckled like other mammals. Cetaceans possess an extensive outer layer of fat associated with their marine habit, have a large brain and are capable of complex communication.

Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
The present study is the first to apply these values to species in the central Pacific, and the resulting g(0) estimates (Table 3) are markedly lower than those used by Barlow (2006), as well as those used in all known previous analyses of line-transect surveys of cetaceans. The g(0) estimates in the present study reflect the effect of the sighting conditions during the HICEAS in 2010, represented by Beaufort sea state, and range from being 1.3 times (78.9%) smaller (i.e., for short-finned pilot whales and Longman's beaked whales) to almost 9 times (11.2%) smaller (i.e., for rough-toothed dolphins) than the g(0) estimates of Barlow (2006).
Although the effect of ship strikes on the population of cetaceans is not serious for the majority of cetaceans, it is a significant human-related threat, indeed perhaps the most important in Sri Lankan waters for the larger cetaceans.
The sightings were reported by the Cetacean Population Study Team researching along the Sindhudurg coast for the past six months under the United Nations Development Programme (UNDP) project on Mainstreaming Coastal and Marine Biodiversity and implemented by the Maharashtra State Mangrove Cell.
If it is collected by cetacean [the genus of mammals which inclued whales, dolphins and porpoises] monitoring, it will undergo an autopsy, but there is a quota each year."
During 2008-2013, we flew 87,734 km of line transect and "focal follow" aerial survey effort in the Southern California Bight to systematically collect data on 2,707 sightings of ~222,457 individual cetaceans representing 19 species, funded by the U.S.
Almost always in motion, cetaceans spend only 20% or less of their time at the water's surface.
Cetaceans, unlike fish, have strong affection for humans; whenever they encounter a boat, they would follow it or circle around it within a certain distance, as if a good friendship is developing between humans and these nonhuman animals.
Retrospective serologic testing from eastern Australia has confirmed seropositivity to morbillivirus in several species; these temporal data suggest circulation of a morbillivirus among cetaceans in this region as long ago as 1985 (3).
The objectives of the present study were the following: (a) to assess the distribution of cetaceans in the Vitoria-Trindade seamounts and adjacent oceanic waters; (b) to verify the presence of humpback whales in the seamounts based on visual and acoustic detection; and (c) to provide new information concerning the breeding stock identity of the humpback whales that breed in Brazilian waters.
coeruleoalba was the second most abundant species sighted in the western tropical Indian Ocean (14% of all cetaceans) in their survey.
He told the Press Association: "We're looking at different possibilities - chemical contaminants in the environment, physical pollution such as plastics, noise pollution from shipping and certain offshore industries, bycatch from fishing, or a different cause of death altogether." Despite the growing public concern about plastic pollution, the impact on cetaceans in UK waters appears to be low at the moment compared with other parts of the world.
Karl Stevens, Hebridean Whale Trail manager, said: "People currently visit Scotland for the landscapes, wildlife and culture - but not necessarily to see cetaceans.