Gray's Beaked Whale

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Gray's Beaked Whale

Size comparison against an average human

Data deficient (DD)

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Cetacea
Suborder:	Odontoceti
Family:	Ziphidae
Genus:	Mesoplodon
Species:	M. grayi

Binomial name

Mesoplodon grayi
von Haast, 1876

Gray's Beaked Whale range

Gray's Beaked Whale (Mesoplodon grayi), sometimes known as Haast's Beaked Whale or the Scamperdown Whale is one better known members of the genus Mesoplodon. The scientific name is in reference to John Edward Gray, a zoologist at the British Museum. This species is fairly gregarious and strands relatively frequently for a beaked whale. It is notable for being the only beaked whale, other than Shepherd's Beaked Whale (not a Mesoplodon), that has numerous teeth.

1 Physical Description
2 Behavior
3 Population and Distribution
4 Conservation
5 References
6 External links

[edit] Physical Description

Gray's beaked whale is a fairly slender member of the genus. The melon on the whale bulges towards the blowhole and slopes down towards the beak. The beak itself is very long and pointed for a beaked whale, and has a relatively strait mouth line. In both sexes there are 17-22 rows of small teeth located towards the back of the mouth which barely protrude past the gum. In males, there are two small, triangular teeth present halfway down the mouth. The overall coloration is dark on top and light below, and both genders have a white beak. Females are lighter on top and have additional white marking near the genitals. Adult males have typical scars from fighting and cookiecutter sharks normally present in the genus. Females reach at least 5.3 meters (17 feet 6 inches) whereas males reach 5.7 meters (19 feet) and weigh around 1100 kilograms (2400 pounds). They are believed to be around 2.4 meters (7 feet 10 inches) long when born.

[edit] Behavior

This species has a tendency to strand in large groups, once involving 20 individuals. Other strandings involved groups of 5 or 6 animals, and sometimes 8. The upper teeth may be used in holding prey, but it not clear why only this species has them.

[edit] Population and Distribution

This species typically lives in the Southern Hemisphere between 30 and 45 degrees. Many strandings have occurred off of New Zealand, but others have happened off of Australia, South Africa, South America, and the Falkland Islands. This species has been sighted in groups off the coast of Madagascar and in the Antarctic area. Somewhat oddly, one specimen has stranded off the Netherlands, on a different Hemisphere and several thousand miles away from all other strandings. No population estimates exist, but they are believed to be rather common.

[edit] Conservation

These whale have not been hunted deliberately and they have not been entangled in fishing gear.

[edit] References

Cetaceans Portal

Cetacean Specialist Group (1996). Mesoplodon grayi. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.
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

[edit] External links

Category: Toothed whales