Beluga whale

Beluga whale[1]
Temporal range:
A beluga whale
At City of Arts and Sciences, Spain
Size comparison to an average human
Size compared to an average human
CITES Appendix II (CITES)[3]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Monodontidae
Genus: Delphinapterus
Lacépède, 1804
Species:
D. leucas
Binomial name
Delphinapterus leucas
(Pallas, 1776)
Beluga range

The beluga whale (/bɪˈlɡə/;[4] Delphinapterus leucas) is an Arctic and sub-Arctic cetacean. It is one of two members of the family Monodontidae, along with the narwhal, and the only member of the genus Delphinapterus. It is also known as the white whale, as it is the only cetacean to regularly occur with this colour; the sea canary, due to its high-pitched calls; and the melonhead, though that more commonly refers to the melon-headed whale, which is an oceanic dolphin.

The beluga is adapted to life in the Arctic, with anatomical and physiological characteristics that differentiate it from other cetaceans. Amongst these are its all-white colour and the absence of a dorsal fin, which allows it to swim under ice with ease.[5] It possesses a distinctive protuberance at the front of its head which houses an echolocation organ called the melon, which in this species is large and deformable. The beluga's body size is between that of a dolphin and a true whale, with males growing up to 5.5 m (18 ft) long and weighing up to 1,600 kg (3,530 lb). This whale has a stocky body. Like many cetaceans, a large percentage of its weight is blubber (subcutaneous fat). Its sense of hearing is highly developed and its echolocation allows it to move about and find breathing holes under sheet ice.

Belugas are gregarious and form groups of 10 animals on average, although during the summer, they can gather in the hundreds or even thousands in estuaries and shallow coastal areas. They are slow swimmers, but can dive to 700 m (2,300 ft) below the surface. They are opportunistic feeders and their diets vary according to their locations and the season. The majority of belugas live in the Arctic Ocean and the seas and coasts around North America, Russia, and Greenland; their worldwide population is thought to number around 200,000.[6][7] They are migratory and the majority of groups spend the winter around the Arctic ice cap; when the sea ice melts in summer, they move to warmer river estuaries and coastal areas. Some populations are sedentary and do not migrate over great distances during the year.

The native peoples of North America and Russia have hunted belugas for many centuries. They were also hunted by non-natives during the 19th century and part of the 20th century. Hunting of belugas is not controlled by the International Whaling Commission, and each country has developed its own regulations in different years. Currently, some Inuit in Canada and Greenland, Alaska Native groups and Russians are allowed to hunt belugas for consumption as well as for sale, as aboriginal whaling is excluded from the International Whaling Commission 1986 moratorium on hunting. The numbers have dropped substantially in Russia and Greenland, but not in Alaska and Canada. Other threats include natural predators (polar bears and killer whales), contamination of rivers (as with polychlorinated biphenyl (PCBs) which bioaccumulate up the food chain), climate change and infectious diseases. The beluga was placed on the International Union for Conservation of Nature's Red List in 2008 as being "near threatened"; the subpopulation from the Cook Inlet in Alaska is considered critically endangered and is under the protection of the United States' Endangered Species Act. Of all seven extant Canadian beluga populations, those inhabiting eastern Hudson Bay, Ungava Bay, and the St. Lawrence River are listed as endangered.

Belugas are one of the most commonly kept cetaceans in captivity and are housed in aquariums, dolphinariums and wildlife parks in North America, Europe and Asia. They are considered charismatic because of their docile demeanour and characteristic smile, communicative nature,[8] and supple, graceful movement.[9]

  1. ^ Mead, J. G.; Brownell, R. L. Jr. (2005). "Order Cetacea". In Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 735. ISBN 978-0-8018-8221-0. OCLC 62265494.
  2. ^ Lowry, L.; Reeves, R.; Laidre, K. (2017). "Delphinapterus leucas". IUCN Red List of Threatened Species. 2017: e.T6335A50352346. doi:10.2305/IUCN.UK.2017-3.RLTS.T6335A50352346.en. Retrieved 12 November 2021.
  3. ^ "Appendices | CITES". cites.org. Archived from the original on 5 December 2017. Retrieved 14 January 2022.
  4. ^ "beluga". Oxford English Dictionary (Online ed.). Oxford University Press. doi:10.1093/OED/4456975553. (Subscription or participating institution membership required.)
  5. ^ Bradford, Alina (20 July 2016). "Facts About Beluga Whales". Live Science. Archived from the original on 3 May 2019. Retrieved 12 June 2019.
  6. ^ "Global Review of the Conservation Status of Monodontid Stocks | Scientific Publications Office". spo.nmfs.noaa.gov. Archived from the original on 25 November 2020. Retrieved 2 January 2021.
  7. ^ Vacquié-Garcia, J; Lydersen, C; Marques, TA; Andersen, M; Kovacs, KM (27 February 2020). "First abundance estimate for white whales Delphinapterus leucas in Svalbard, Norway". Endangered Species Research. 41: 253–263. doi:10.3354/esr01016. hdl:10023/19740.
  8. ^ "Baby Beluga, Smithsonian Ocean". Smithsonian Institution. Archived from the original on 3 March 2021. Retrieved 20 January 2021.
  9. ^ Gibbons, Whit (27 May 2012). "Ecoview | BELUGA WHALES ARE COOL". Savannah River Ecology Laboratory, University of Georgia. Archived from the original on 15 April 2021. Retrieved 20 January 2021.

Beluga whale

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