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 genus.
Sowerby's Beaked Whale has a typical body shape for the genus, and is mainly distinguished by the male's dual teeth positioned far back in the mouth. The whale's beak is moderately long, and the melon
is slightly convex. The colouration pattern is a grey with light countershading
on the bottom, and frequently has cookie cutter shark
bites and scars from teeth (in males). The whale reaches 5 metres
(16 ft) in females and 5.5 metres (18 ft) in males, with a weight of 1000-1300 kilograms
(2200-2900 lb). The gestation period lasts for 12 months and the young are born at a length of 2.4 to 2.7 metres (8 to 9 ft) with a weight of around 185 kilograms (400 lb).
Population and distribution
Sowerby's Beaked Whale ranges from Nantucket
in the Western Atlantic and from Madeira
to the Norwegian Sea
in the Eastern Atlantic. They typically range in waters 200 to 1,500 metres (650 to 5,000 ft) deep. No population estimates have been made.
Sowerby’s Beaked Whales are reclusive creatures that stay away from ships and are rarely sighted. The whales are occasionally in groups of 8 to 10 individuals (males, females, and calves) and have been known to strand in groups as well. They are believed to primarily feed on squid
, but cod
has also been found in their stomachs. They have been known to dive down at times approaching 30 minutes.
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.
- 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