Gervais' Beaked Whale
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 Size comparison against an average human
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| Mesoplodon europaeus (Gervais, 1855) |
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 Gervais' Beaked Whale range
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Gervais' Beaked Whale (Mesoplodon europaeus), sometimes known as the Antillian Beaked Whale, Gulf Stream Beaked Whale, or European Beaked Whale (from which its scientific name is derived) is the most frequently stranding type of Mesoplodont whale off the coast of North America. It has also stranded off South America and Africa.
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[edit] Physical description
This species is rather gracile, elongated, and laterally compressed compared with other mesoplodonts. The mouthline is remarkably straight, even in males, and the two teeth of the male erupt towards the tip of the beak, and are hardly noticeable. The head is overall small and tapering in outline. The melon only bulges very slightly. The coloration is dark gray on top and lighter gray on bottom. Females sometimes have lighter spots near the genitals and face, with a dark circle remaining around the eyes. Juveniles start off with a lighter coloration, but soon darken. Males are 4.5 meters (15') in length and females are at least 5.2 meters (17') and probably weigh more than 1200 kg (2600 pounds). Calves are believed to be 2.1 meters (7 feet) in length. One beached specimen may have been 48 years old.
[edit] Population and distribution
The whale originally beached in England, but has since been found off Ireland, the Canary Islands, Western Africa, and Ascention Island. In August 2001, a specimen was found off São Paulo, Brazil, and is the southernmost the whale has been found to date. The population is believed to be naturally rare, and no estimates have been attempted.
It is remarkable that although this whale frequently strands (first observed in 1840), until 1998 no human saw a live specimen: Since then only 10 other sightings have happened.
[edit] Behavior
Judging by beachings, the whales inhabit small groups. They probably feed on squid.
They can dive deep : The first 1998 sighting (west of the island of Tenerife) observed three whales at a depth of 1500 meters.
Another small group was seen south of the island of Gran Canaria : Although timid, the whales allowed close photos. It was reported that they surface for short time, and their dives last for around an hour [1].
In September 2008, northeast of the island of Lanzarote, some Gervais' whales were photographed doing high jumps above water [2].
[edit] Conservation
The species has not been hunted and only very infrequently gets tangled up in fishing nets.
[edit] References
- Taylor, B.L., Baird, R., Barlow, J., Dawson, S.M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L. (2008). Mesoplodon europaeus. 2008 IUCN Red List of Threatened Species. IUCN 2008. Retrieved on 24 March 2009. Database entry includes a brief justification of why this species is of data deficient.
- 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
- A Gervais' beaked whale (Mesoplodon europaeus) washed ashore in southeastern Brazil: extra limital record? Santos, Zampirolli, Castro, and Alarenga. Aquatic Mammals 2003. 29.3, 404-410. Available: here
- Red Canaria de Varamientos (Vonk & Martín 1988; Martín & Carrillo, 1992; Martín et al. 1995;Carrillo & Martín, 2000; Carrillo & Tejedor, 2002, 2003, 2004)
- Estudios aplicados a la conservación de las poblaciones de cetáceos en la provincia de Santa Cruz de Tenerife. Informe para el Gobierno de Canarias by Carrillo, M. and Tejedor M. 2002 (Tenerife Conservación - Biblioteca pública del Centro de Planificación Ambiental de la Laguna – Tenerife)
[edit] External links
- ARKive - images and movies of the Gervais's beaked whale (Mesoplodon europaeus)
- Cetaceans of the World
- CMS
- Whale & Dolphin Conservation Society (WDCS)
- Sightings of Gervais' beaked whales in the Canary Islands (Spanish)
