Bowhead Whale
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Chobot
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robot Adding: [[ko:북극고래]]
{{Taxobox
| name = Bowhead Whale
| status = LR/cd | status_system = IUCN2.3
| status_ref =<ref>{{IUCN2006|assessors=Cetacean Specialist Group|year=1996|id=2467|title=Balaena mysticetus|downloaded=6 May 2006}} Database entry includes a lengthy justification of why this species is dependent on conservation </ref>
| image = Bowheads42.jpg
| image_width = 250px
| image2 = Bowhead_whale_size.svg
| image2_width = 250px
| image2_caption = Size comparison against an average human
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Mammal]]ia
| subclassis = [[Eutheria]]
| ordo = [[Cetacea]]
| subordo = [[Baleen whale|Mysticeti]]
| familia = [[Balaenidae]]
| genus = '''''Balaena'''''
| species = '''''B. mysticetus'''''
| binomial = ''Balaena mysticetus''
| binomial_authority = [[Carl Linnaeus|Linnaeus]], [[1758]]
| range_map = Cetacea range map Bowhead Whale.png
| range_map_width = 250px
| range_map_caption = Bowhead whale range
}}
The '''Bowhead Whale''' (''Balaena mysticetus''), also known as '''Greenland Right Whale''' or '''Arctic Whale''', is a [[baleen whale]] of the right whale family [[Balaenidae]]. A stocky dark-colored whale without a dorsal fin, it can grow to 20 [[metre|meter]]s (66 [[foot (length)|ft]]) in length. Estimated maximum weight of this thick-bodied species is 136 tonnes (152 tons), second only to the [[Blue Whale]], although the Bowhead lags behind several other whales in maximum length. The Bowhead spends all of its life in fertile [[Arctic Ocean|Arctic]] waters, unlike other whales that migrate for feeding or reproduction.
The Bowhead was an early target for the [[whaling]] industry, and its population was severely depleted before a whaling moratorium was introduced in 1966. The population is estimated to be over 11,700 worldwide, down from an estimated 50,000 before the commencement of whaling.
==Taxonomy==
{{seealso|Evolution of cetaceans}}
The Bowhead Whale was described by [[Carl Linnaeus]] in the 10th edition of his ''[[Systema Naturae]]'' (1758).<ref>{{la icon}} {{cite book | last=Linnaeus | first=C | authorlink=Carolus Linnaeus | title=Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. | publisher=Holmiae. (Laurentii Salvii). | date=1758| pages=824 | url=http://dz1.gdz-cms.de/index.php?id=img&no_cache=1&IDDOC=265100}}</ref> ''Balaena'' has remained a monotypic genus ever since. '''''Leiobalaena''''', described by Eschricht in 1849, is a [[synonym (taxonomy)|junior synonym]].
The Bowhead Whale is an individual species, separate from the other [[right whale]]s. It has always been recognized as such, and stands alone in its own genus as it has done since the work of [[John Edward Gray|Gray]] in 1821. There is, however, little genetic evidence to support this two-genera view. Indeed, scientists see greater differences between the members of ''[[Balaenoptera]]'' than between the Bowhead and the right whales. Thus, it is likely that all four species will be placed in one genus in some future review.<ref name=EOMM>{{cite book | last = Kenney | first = Robert D. | editor = William F. Perrin, Bernd Wursig and J. G. M. Thewissen | title = The Encyclopedia of Marine Mammals | year = 2002 | publisher = Academic Press | id = ISBN 0-12-551340-2 | pages = 806-813 | chapter = North Atlantic, North Pacific and Southern Right Whales}}</ref>
It is thought that ''Balaena prisca'', one of the five ''Balaena'' [[fossil]]s from the late [[Miocene]] (~10 [[mya (unit)|mya]]) to early [[Pleistocene]] (~1.5 mya), may be the same as the modern Bowhead Whale. Prior to these there is a long gap back to the next related cetacean in the fossil record, ''Morenocetus'', which was found in a [[South America]]n deposit dating back 23 million years.
==Description==
Bowhead Whales are robust-bodied, dark-colored animals with no [[dorsal fin]] and a strongly bowed lower jaw and narrow upper jaw. The [[baleen]] plates, exceeding three meters and the longest of the baleen whales, are used to strain tiny prey from the water. The whales have massive bony [[skull]]s which they use to break the ice from beneath to breathe. Some [[Inuit]] hunters have reported whales surfacing through 60 cm (2 [[foot (length)|ft]]) of ice in this method. Bowheads may reach lengths of up to 20 meters and females are larger than males. The [[blubber]] layer of whale flesh is thicker than in any other animal, averaging 43–50 cm (17–20 [[inch|in]]). The longest reported length for a Bowhead, was 21.2 m (70 feet) for an unweighed giant caught off of [[Svalbard|Spitsbergen]], [[Norway]].<ref><Wood, The Guinness Book of Animal Facts and Feats. Sterling Pub Co Inc (1983), ISBN 978-0851122359></ref>
==Distribution==
Bowhead Whales are the only [[baleen whale]]s that spend their entire lives in and around [[Arctic]] waters. Those found off [[Alaska]] spend the winter months in the southwestern [[Bering Sea]]. They migrate northward in the spring, following openings in the pack ice, into the [[Chukchi Sea|Chukchi]] and [[Beaufort Sea|Beaufort]] seas, hunting [[zooplankton]] such as [[copepod]]s. Bowheads are slow swimmers and usually travel alone or in small herds of up to six animals. Although they may stay below the water surface for as long as forty minutes in a single dive, they are not thought to be deep divers.
==Reproduction and lifespan==
[[Image:Faroe stamp 198 Baleana mysticetus.jpg|thumb|right|250px|Bowhead Whale (on [[Faroe Islands|Faroese]] stamp)]]
Bowhead Whales are highly vocal and use underwater sounds to communicate while traveling, feeding, and socializing. Some Bowheads make long repetitive songs that may be mating displays. The whales' [[Whale#behavior|behavior]] can also include [[Whale surfacing behaviour#Breaching, lunging and porpoising|breaching]], [[Whale surfacing behaviour#lobtailing and slapping|tail slapping]], and [[Whale surfacing behaviour#Spyhopping|spyhopping]]. Sexual activity occurs between pairs and in boisterous groups of several males and one or two females.
Breeding has been observed from March through August; conception is believed to occur primarily in March. Reproduction can begin when a whale is 10 to 15 years old. Females produce a calf once every 3 to 4 years, after a 13 to 14 month pregnancy. The newborn calf is about 4.5 m (15 ft) long and approximately 1000 kg (2,200 [[pound (mass)|lb]]), growing to 9 m (30 ft) by its first birthday.
The lifespan of a Bowhead was once thought to be 60 to 70 years, similar to other whales. However, discoveries of antique ivory spear points in living whales in 1993, 1995, 1999, and 2007 have triggered further research based on structures in the whale's eye, leading to the reliable conclusion that at least some individuals have lived to be 150–200 years old (another report has said a female at the age of 90 was allegedly still reproductive).<ref>[http://www.gi.alaska.edu/ScienceForum/ASF15/1529.html Bowhead Whales May Be the World's Oldest Mammals]</ref>
In May 2007, a 50 [[ton]] specimen caught and harvested off the Alaskan coast was discovered to have the head of an explosive harpoon embedded deep under the blubber of its neck. Examination determined the 3 1/2 inch arrow-shaped projectile was manufactured in [[New Bedford, Massachusetts|New Bedford]], [[Massachusetts]], a major whaling center, around 1890. This proof that it survived a similar hunt more than a century ago indicated to researchers that the whale's age was between 115 and 130 years old.<ref>John C. George, Jeffrey Bada, Judith Zeh, Laura Scott, Stephen E. Brown, Todd O'Hara, and Robert Suydam (1999) Age and growth estimates of bowhead whales (''Balaena mysticetus'') via aspartic acid racemization. Can. J. Zool. 77(4): 571–580</ref><ref>[http://www.msnbc.msn.com/id/19195624/]</ref><ref>http://science.propeller.com/story/2007/06/12/19th-century-weapon-found-in-whale</ref>
Because of their possible lifespans, female Bowhead Whales are believed to go through [[menopause]]. Observations of very large animals without calves support this hypothesis.<ref>[http://news.nationalgeographic.com/news/2006/07/060713-whale-eyes.html Rare Whales Can Live to Nearly 200, Eye Tissue Reveals]</ref>
==Population status==
[[Image:18th century arctic whaling.jpg|thumb|200px|right|Eighteenth century engraving showing Dutch whalers hunting Bowhead Whales in the [[Arctic]]. [[Beerenberg]] on [[Jan Mayen|Jan Mayen Island]] can be seen in the background.]]
Bowhead Whales have been [[whaling|hunted]] for their [[blubber]], meat, [[whale oil|oil]], bones, and [[baleen]]. They are closely related to the [[right whale]] and share with it the hunting-ideal characteristics of slow swimming and floating after death. Before commercial whaling, there were over 50,000 Bowhead Whales in the north polar region (estimated).{{Fact|date=August 2007}} Commercial whaling began in the 16th century, when the Basques hunted Bowhead Whales migrating south through the [[Strait of Belle Isle]] in the fall and early winter. In 1611, the first whaling expedition was sent to [[Spitsbergen]], and by mid-century the population(s) there had practically been wiped out, forcing whalers to begin voyaging into the "West Ice"- the pack ice off the east coast of [[Greenland]]. By 1719, whalers had reached the [[Davis Strait]], and by the first quarter of the 19th century [[Baffin Bay]]. In the [[Pacific Ocean|North Pacific]], commercial whaling began in the 1840s, and within two decades over 60 percent of the Bowhead Whale population had been wiped out.
Commercial whaling, the principal cause of the population decline, has been discontinued. The population off [[Alaska]] has increased since commercial whaling ceased. [[Alaska Natives]] continue to kill small numbers of Bowhead Whales in [[Subsistence economy|subsistence hunt]]s each year. This level of killing (25–40 animals annually) is not expected to affect the population's recovery. The Bowhead Whale population off Alaska's coast (also called the Bering-Chukchi-Beaufort stock) appears to be recovering but remains at about 10,500 animals (2001). The status of the other Bowhead populations is less well known. There are about 1,200 Bowheads off West Greenland (2006), while the Spitsbergen Bowhead population may only number in the tens.
In March, 2008, Canada's Department of Fisheries and Oceans stated that previous estimates of the Eastern Arctic bowhead population had undercounted the number of whales in the region, with a new estimate of 14,400 animals (r. 4,800-43,000){{Fact|date=June 2008}}. These larger numbers would correspond to the estimates of the whale population before whaling, indicating that this population has recovered.
The Bowhead is listed in Appendix I by [[CITES]] (that is, "threatened with extinction"). It is listed as endangered under the auspices of the United States' [[Endangered Species Act]]. The [[IUCN Red List]] data is as follows:
[[Image:GreenlandWhaleLyd3.jpg|thumb|Skeleton of a Bowhead Whale]]
*[[Spitsbergen]] population - ''Critically endangered''
*[[Sea of Okhotsk]] subpopulation - ''Endangered''
*[[Baffin Bay]]-[[Davis Strait]] stock - ''Endangered''
*[[Hudson Bay]]-[[Foxe Basin]] stock - ''Vulnerable''
*[[Bering Sea|Bering]]-[[Chukchi Sea|Chukchi]]-[[Beaufort Sea|Beaufort]] stock - ''Lower risk - conservation dependent''
==Behavior and predators==
{{Refimprovesect|date=December 2007}}
Unlike most other baleen whales which primarily feed on concentrated shoals of prey species, Bowheads (and Right Whales) feed in a manner similar to Basking Sharks by swimming forward with their mouths agape and continuously filtering water through their baleen plates. Thus, they specialize in feeding on much smaller prey items such as copepods. Their mouth with the large upturning lip on the lower jaw helps to reinforce and contain the baleen plates within their mouth, and prevent buckling or breakage of the plates due to the pressure of the water passing through them as they swim forward. This is in contrast to the Rorquals which have distendable ventral pleats that they fill with water containing prey, which is then pushed out and filtered through the baleen plates in distinct batches.
Bowheads are social and nonaggressive, and will retreat under the ice when threatened. Their only predators are [[human]]s and [[orca]]s. On rare occasions, Bowheads are also attacked by [[sea lion]]s.
{{cetaceaportal}}
==References==
{{reflist}}
==See also==
*[[Ottawa Islands#Fauna|Ottawa Islands - Fauna]]
==External links==
{{Commons|Balaena mysticetus}}
{{Wikispecies|Balaena mysticetus}}
*[http://www.wdcs.org Whale and Dolphin Conservation Society (WDCS)]
*ARKive - [http://www.arkive.org/species/GES/mammals/Balaena_mysticetus/ images and movies of the bowhead whale ''(Balaena mysticetus)'']
*[http://nmml.afsc.noaa.gov/education/cetaceans/bowhead2.htm Bowhead Whale: Detailed Information from NOAA]
*[http://www.worldhistoryblog.com/2007/06/harpoon-may-prove-whale-was-at-least.html Harpoon may prove whale was at least 115 years old]
*[http://www.cbc.ca/canada/north/story/2008/04/16/science-bowhead-arctic.html Eastern Arctic bowhead whales not threatened]
{{Cetacea|M.}}
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[[Category:Arctic cetaceans]]
[[Category:Baleen whales]]
[[Category:Alaska culture]]
[[Category:Megafauna of Eurasia]]
[[Category:Megafauna]]
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[[es:Balaena mysticetus]]
[[eo:Baleno gronlanda]]
[[fa:نهنگ گرینلندی]]
[[fr:Baleine boréale]]
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[[ko:북극고래]]
[[it:Balaena mysticetus]]
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[[ja:ホッキョククジラ]]
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