Salvin's albatross

Salvin's albatross (Thalassarche salvini) or Salvin's mollymawk, is a large seabird that breeds only in islands in New Zealand's realm. A medium-sized mollymawk in the albatross family, it was long considered to be a subspecies of the shy albatross. It is a medium-sized black and white albatross.

Salvin's albatross
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Procellariiformes
Family: Diomedeidae
Genus: Thalassarche
Species:
T. salvini
Binomial name
Thalassarche salvini
Synonyms

Thalassarche cauta salvini

Taxonomy

Mollymawks are a type of albatross that belong to the family Diomedeidae in the order Procellariiformes, along with shearwaters, fulmars, storm petrels, and diving petrels. They share certain identifying features. First, they have nasal passages that attach to the upper bill called naricorns. Although the nostrils on the albatross are on the sides of the bill, unlike other tubenosed seabirds. The bills of Procellariiformes are also unique in that they are split into between seven and nine horny plates. They produce a stomach oil made up of wax esters and triglycerides that is stored in the proventriculus. This is used against predators as well as an energy rich food source for chicks and for the adults during their long flights.[3] Finally, they have a salt gland that is situated above the nasal passage and helps desalinate their bodies, due to the high amount of ocean water that they imbibe. It excretes a high saline solution from their nose.[4]

The Salvin's albatross, white-capped albatross, shy albatross and Chatham albatross were all considered the same species until a 1998 article by Robertson and Nunn.[5] Other experts followed suit, with BirdLife International in 2000,[6] Brooke in 2004,[7] ACAP in 2006,[8] and SACC in 2008.[9][10][11] Some, however, like James Clements (at the time of his death) didn't agree, nor has Cornell University since (which is responsible for his book).[12] Molecular analysis has shown that it and the closely related Chatham albatross (also considered to be a subspecies of the shy albatross) are sister taxa, and more distantly related to the shy.

Etymology

The species was named by Lord Lionel Walter Rothschild for the distinguished ornithologist Osbert Salvin.

Description
In flight

The Salvin's albatross is about 90 cm (35 in) and 2.56 m (8.4 ft) across the wings. It weighs 3.3–4.9 kg (7.3–10.8 lb) and is, alongside the shy albatross, the largest of the mollymawk or small albatross group.[13] The adult bird has a silver-grey crown. Its face, upper throat, and upper mantle are grey, and its back, upperwing, and tail are grey-black. It has a white rump and underparts with a black thumbmark on underwing and black narrow leading and trailing edges on the wing and black wing tips. Its bill is pale grey-green with a pale yellow upper ridge, and a bright yellow tip on the upper mandible, and a dark spot on the tip of the lower mandible. The juveniles have more extensive grey areas and a blue-grey bill with black tips on both mandibles.[6] It can be distinguished from the Chatham albatross by its larger size and grey bill, and from the shy albatross by the greyer head. Such differences can be difficult to pick out at sea, however, and this explains the under-representation of this species in at-sea surveys.

Behavior

Feeding

Salvin's albatross feeds mainly on fish and cephalopods.[14]

Reproduction
Breeding Population and Trends[6]
Location Population Date Trend
Bounty Islands30,750 pairs1998Possibly declining
Western Chain Islets, Snares Islands< 650 pairs1984
The Pyramid, Chatham Islands2 pairs2006
Forty-Fours1+ pairs2007
Île des Pingouins, Crozet Islands1—4 pairs2002
Total62,0001998Possibly declining

It breeds mainly on small rocky islands with little vegetation,[15] and the nest is a pedestal made of mud, feathers, and bird bones.[16] A single egg is laid in September, and incubated by both parents until early November. The chicks fledge after about 4 months.

Range and habitat

The Salvin's albatross breed colonially on three disparate island groups in the Southern Ocean, Île des Pingouins in the Crozet Islands in the Indian Ocean[7][17] and the Bounty Islands and The Snares to the south of New Zealand, The Pyramid, and Forty-Fours Island.[15][18][19] At sea they range from South Africa across to Australia and as far east as the coast of South America.

Conservation

The IUCN classifies this species as vulnerable[1] with longline fisheries and trawlers responsible for small numbers of deaths, although trawlers are responsible for more than half of those killed. The world population is currently estimated to be around 61,500 birds in 1998,[20][21] which suggests a decline in the species since earlier studies (although differences in methods make direct comparisons difficult). There are 30,750 pairs, in 1998, on the Bounty Islands, compared to 76,000 pairs in 1978.[16] There were 650 pairs on the Snares Islands, and 4 pairs were recorded on Île des Pingouins in the Crozet Islands.[7][17] Single chicks have been observed on The Pyramid and Forty-fours Island in 2007.[22]

Bird banding[15] and studies[18] are underway, and all of the islands except for The Pyramid, and Forty-fours Island, which are privately owned, are nature preserves. In 1998, the Snares Islands and Bounty Islands were declared World Heritage Sites, and in 2006, the Western and Central Pacific Fisheries Commission adopted a measure to require bird bycatch mitigation measures south of 30°S.[6]

Footnotes
  1. BirdLife International (2012). "Thalassarche salvini". IUCN Red List of Threatened Species. 2012. Retrieved 26 November 2013.CS1 maint: ref=harv (link)
  2. Brands, S. (2008)
  3. Double, M. C. (2003)
  4. Ehrlich, Paul R. (1988)
  5. Robertson, C. J. R. & Nunn, G. B. (1998)
  6. BirdLife International (2008)
  7. Brooke, M. (2004)
  8. ACAP (2007)
  9. Remsen Jr., J. V. (2004)
  10. Remsen Jr., J. V. (2005)
  11. Remsen Jr., J. V. (2008)
  12. Clements, J. (2007)
  13. Brooke, Michael, Albatrosses and Petrels across the World (Bird Families of the World). Oxford University Press (2004), ISBN 978-0-19-850125-1
  14. Marchant, S. & Higgins, P. J. (1990)
  15. Croxall, J. P. & Gales, R. (1998)
  16. Robertson, C. J. R. & van Tets (1982)
  17. Jouventin, P. (1990)
  18. Taylor, G. A. (2000)
  19. Miskelly, C. M., et al. (2006)
  20. Booth, A. M. (1999)
  21. Clark, G., et al. (1998)
  22. Robertson, C. J. R. (2008)

References
  • ACAP (2007). "ACAP species". ACAP. Archived from the original on January 5, 2009. Retrieved 22 Feb 2009.
  • Baird, S. J.; Smith, M. H. (2007). "Incidental capture of seabirds species in commercial fisheries in New Zealand waters, 2003-2004 and 2004-2005". New Zealand Aquatic Environment and Biodiversity Report (9).
  • BirdLife International (2008). "Salvin's Albatross - BirdLife Species Factsheet". Data Zone. Retrieved 22 Feb 2009.
  • Booth, A. M. (1999) in litt
  • Brands, Sheila (August 14, 2008). "Systema Naturae 2000 / Classification - Subfamily Diomedeinae". Project: The Taxonomicon. Retrieved 22 Feb 2009.
  • Brooke, M. (2004). "Procellariidae". Albatrosses And Petrels Across The World. Oxford, UK: Oxford University Press. ISBN 0-19-850125-0.
  • Clark, G.; Booth, A. M.; Amey, J. (1998). Unpublished Report. Invercargill, N.Z: NZ Department of Conservation.CS1 maint: untitled periodical (link)
  • Clements, James (2007). The Clements Checklist of the Birds of the World (6th ed.). Ithaca, NY: Cornell University Press. ISBN 978-0-8014-4501-9.
  • Croxall, J. P.; Gales, R. (1998). "Assessment of the conservation status of albatrosses". In Robertson, G.; Gales, R. (eds.). Albatross biology and conservation. Chipping Norton, Australia: Surrey Beatty & Sons.
  • Double, M. C. (2003). "Procellariiformes (Tubenosed Seabirds)". In Hutchins, Michael; Jackson, Jerome A.; Bock, Walter J.; Olendorf, Donna (eds.). Grzimek's Animal Life Encyclopedia. 8 Birds I Tinamous and Ratites to Hoatzins. Joseph E. Trumpey, Chief Scientific Illustrator (2nd ed.). Farmington Hills, MI: Gale Group. pp. 107–111. ISBN 0-7876-5784-0.
  • Ehrlich, Paul R.; Dobkin, David, S.; Wheye, Darryl (1988). The Birders Handbook (First ed.). New York, NY: Simon & Schuster. pp. 29–31. ISBN 0-671-65989-8.
  • Jouventin, P. (1990). "Shy Albatrosses Diomedea cauta salvini breeding on Penguin Island, Crozet Archipelago, Indian Ocean". Ibis. 132: 126–127. doi:10.1111/j.1474-919x.1990.tb01026.x.
  • Marchant, S.; Higgins, P. J. Handbook of Australian, New Zealand and Antarctic birds, 1: ratites to ducks. Melbourne, Australia: Oxford University Press. ISBN 978-0-19-553068-1.
  • Miskelly, C. M.; Bester, A. J.; Bell, M. (2006). "Additions to the Chatham Islands' bird list, with further records of vagrant and colonising bird species". Notornis (53): 215–230.
  • Remsen Jr., J. V.; et al. (December 2004). "Proposal #155 to South American Check-list Committee: Split Shy Albatross Thalassarche cauta into two or three species". South American Classification Committee. American Ornithologists' Union. Archived from the original on 2008-05-16. Retrieved 18 Feb 2009.
  • Remsen Jr., J. V.; et al. (February 2005). "Proposal (#166) to South American Classification Committee: Re-lump Thalassarche eremita and Thalassarche salvini with Thalassarche cauta". South American Classification Committee. American Ornithologists' Union. Archived from the original on 2008-05-08. Retrieved 18 Feb 2009.
  • Remsen Jr., J. V.; et al. (28 Feb 2008). "Proposal (#255) to South American Classification Committee : Follow-up to Proposal 155: Split Thalassarche cauta into three species". South American Classification Committee. American Ornithologists' Union. Archived from the original on 2008-05-16. Retrieved 18 Feb 2009.
  • Robertson, C. J. R.; Nunn, G. B. (1998). "Towards a new taxonomy for albatrosses". In Robertson, G.; Gales, R. (eds.). Albatross biology and conservation. Chipping Norton, Australia: Surrey Beatty & Sons. pp. 13–19.
  • Robertson, C. J. R. (2008) in litt
  • Robertson, C. J. R.; van Tets, G. F. (1982). "The status of birds at the Bounty Islands". Notornis (29): 311–336.
  • Taylor, G. A. (2000). "Action plan for seabird conservation in New Zealand. Wellington: Department of Conservation". Threatened Species Occasional Publication (16).
  • Tickell, W.L.N. (2000). Albatrosses Sussex:Pica press, ISBN 1-873403-94-1
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