Sowerby's Beaked Whale
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{{Taxobox | color = pink | name = Sowerby's Beaked Whale | status = Conservation status: Unknown | image = Faroe stamp 197 Mesoplodon bidens.jpg | image_width = 240px | image_caption = Sowerby's Beaked Whale (on Faroese stamp) | regnum = Animalia | phylum = Chordata | classis = Mammalia | ordo = Cetacea | subordo = Odontoceti | familia = Ziphidae | genus = Mesoplodon | species = M. bidens | binomial = Mesoplodon bidens | binomial_authority = Sowerby, 1804 }}
Sowerby's Beaked Whale (Mesoplodon bidens), also known as the North Atlantic/North Sea Beaked Whale, was the first beaked whale to be described. Its name, bidens, derives from the two teeth present in the jaw, now known to be a very common feature among the family. It is altogether a rather typical representative of the genus.
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Physical description
Sowerby's Beaked Whale has a typical body shape for the genus, and is mainly distinguished by the male's dual teeth erupting very far back in the mouth. The whale's beak is moderately long, and the melon is slightly convex. The coloration pattern is a fairly drab grey with light countershading on the bottom, and frequently has cookie cutter shark bites and scars from teeth (in males). The whale reaches 5 meters (16 feet) in females and 5.5 meters (18 feet) in males, with a weight of 1000 to 1300 kilograms (2200 to 2900 pounds). The gestation period is a full year and the young are born at a length of 2.4 to 2.7 meters (8 to 9 feet) with a weight of around 185 kilograms (400 pounds).
Population and distribution
Sowerby's Beaked Whale ranges from Nantucket to Labrador in the Western Atlantic and from Madeira to the Norwegian Sea in the Eastern Atlantic. They typically range in waters 650 to 5000 feet deep. No population estimates have been made.
Behavior
The whales are occasionally in groups of 8 to 10 individuals, males, females, and calves. They have been known to strand in groups as well. They are believed to primarily feed on squid, but cod has been found in their stomachs. They have been known to dive down at times approaching half an hour.
Conservation
The species has been hunted infrequently by Norwegians, but such practices have long since been abandoned. There are some deaths due to entanglement in fishing gear, but it is unlikely to be very damaging to the species.
References
- Encyclopedia of Marine Mammals. Edited by William F. Perrin, Bernd Wursig, and J.G.M Thewissen. Academic Press, 2002. ISBN 0-12-551340-2
- Sea Mammals of the World. Written by Randall R. Reeves, Brent S. Steward, Phillip J. Clapham, and James A. Owell. A & C Black, London, 2002. ISBN 0-7136-6334-0