Grey-headed Albatross
From Wikipedia, the free encyclopedia
| iGrey-headed Albatross | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||
|
|
||||||||||||||
| Scientific classification | ||||||||||||||
|
||||||||||||||
|
|
||||||||||||||
| Thalassarche chrysostoma (Forster, 1785) |
The Grey-headed Albatross, (Thalassarche chrysostoma), also known as the Grey-headed Mollymawk, is a large seabird from the albatross family. It has a circumpolar distribution, nesting on isolated islands in the Southern Ocean and feeding at high lattitudes, further south than any of the other mollymawks. Its name derives from its ashy grey head, neck and throat, while the back, wings and tail are black, and the underwing and belly are white. The bill is black with yellow ridges and an orange tip.
Grey-headed Albatrosses nest in colonies on several islands in the Southern Ocean, with large colonies on South Georgia in the South Atlantic, and smaller colonies on Kerguelen Island, Crozet Island and Prince Edward Island in the Indian Ocean, and Campbell Island off New Zealand. A single egg is laid in a large nest, and incubated for 72 days. Studies in South Georgia's Bird Island have shown that the growing chick is fed 616g of food every 1.2 days, with the chick increasing in weight to around 4900 g. Chicks then tend to lose weight before fledging, which happens after 141 days. Chick will generally not return to the colony for 6-7 years after fledging, and will not breed for the first time until several years after that. If a pair of has managed to sucsessfully raise a chick it will not breed in the following year, taking the year off. During this time spent away from the colony they can cover great distances, often circling the globe several times
At sea the Grey-headed Albatross is highly pelagic, more so than other mollymawks, feeding in the open oceans rather than over the continental shelves. They feed predominantly on squid, taking also some fish. Krill is less important as a food source for this species, reflecting their more pelagic feeding range. They are capable of diving as deep as 7m to chase prey, but do not do so frequently.
[edit] References
- Brooke, M. (2004). Albatrosses And Petrels Across The World: Procellariidae. Oxford University Press, Oxford, UK ISBN 0-19-850125-0
- del Hoyo, Josep, Elliott, Andrew & Sargatal, Jordi (1992). Handbook of Birds of the World Vol 1. Barcelona:Lynx Edicions, ISBN 84-87334-10-5
- Croxall, J. P., Silk, J.R.D., Phillips, R.A., Afanasyev, V., Briggs, D.R., (2005) "Global Circumnavigations: Tracking year-round ranges of nonbreeding Albatrosses" Science 307 249-250.
- BirdLife International (2005). Thalassarche chrysostoma. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is vulnerable
