Short-tailed albatross - Phoebastria albatrus
Taxonomy & Nomenclature
Physical Description / Field Identification
The short-tailed albatross is mostly white, with yellow/buff tinge on their heads and napes. The tip of the tail and distal portion of the wings are dark brown, and their large, pink, bill has a blue tip and is hooked at the end. The feet are pale blue. The short-tailed albatross is a mid-sized albatross, with a length of 90 cm, a wingspan of 220 cm, and a weight of about 8.5 km. Juveniles are chocolate brown, with a large pink bill and flesh colored legs. Young short-tailed albatrosses progressively whiten with age.
Can be Confused With
Two cogeners overlap the short-tailed albatross’ distribution: the Laysan and black-footed albatrosses (P. immutabilis and P. nigripes, respectively). The short-tailed albatross is larger than these species, and can be distinguished by its pink beak. Additionally, mature short-tailed albatross can be distinguished from Laysan albatross by their white back.
Distribution
Short-tailed albatrosses have a cosmopolitan range, though their breeding distribution is restricted to only two locations: the Japanese island of Torishima (a small island 600 km south of Tokyo) and the Senkaku Islands near Taiwan.
This species disperses throughout the North Pacific when it is not breeding. It has been recorded in the Sea of Okhotsk and the coasts of eastern Russia, South Korea, China, Taiwan, Alaska, the Hawaiian Islands, and Baja California. The short-tailed albatross may prefer inshore waters, as indicated by the substantial numbers of skeletons found in middens from California to the St. Lawrence Islands.
Ecology and Behavior
The short-tailed albatross spends long periods of time at sea, coming to land only to breed. Short-tailed albatross usually breed with the same mate year after year, arriving at the breeding grounds in early October and claiming sites nearly identical to nest locations from previous years. Ritual courtship involves displays and vocalizations. Nests consist of depressions in the earth lined with grasses, and open, grassy areas are preferred. Each pair lays and together incubates a single large egg for an average of 65 days, alternating roosting so that each can forage during the incubation period. Nestlings are guarded by adults and fed regurgitated food by both parents. Nestlings remain in the nest extended periods, sometimes more than five months. Adults and juveniles depart the nesting colony by mid-June at the latest. The short-tailed albatross is a long-lived bird that reaches sexual maturity at the age of eight or nine years.
Feeding and Prey
The diet of the short-tailed albatross is not well studied, though it is known that it is dominated by fish > squid > invertebrates. Epipelagic fish, such as Exocoetidae (flying fish) are particularly important, as are cephalopods (Todarodes pacificus). Short-tailed albatross sometimes follow fishing vessels to feed by surface seizing and scavenging on scraps and discards.
Threats and Status
Main threats to short-tailed albatrosses include: fisheries bycatch, oil and plastic pollution, entanglement in debris/fishing gear, and volcanic eruption.
The short-tailed albatross is classified as “Vulnerable” by the IUCN and is considered an endangered species by the United States and Japanese governments. Once abundant, feather hunting in the late nineteenth and early twentieth centuries decimated the population, which was thought to be extinct until the 1950’s. The global population of short-tailed albatross is estimated at 800-1200 individuals and thought to be increasing.
This species is particularly threatened due to its limited breeding range. Only 176 pairs nest on Torishima and 20 pairs nest in the Senkaku Islands. In 2001, a lone pair was found incubating an egg on Yome-jima Island. Torishima is an active volcano, adding the threat of environmental catastrophe to other conservation concerns. Degradation of nesting sites may also affect breeding success, as the grassy areas the short-tailed albatross prefers are limited. Native grasses were planted on the nesting colonies in the 1980’s, reducing blowing volcanic ash. Breeding success after the grasses were planted increased to 66%. Incidental take in longline fisheries is also a pressing concern for conservation of the short-tailed albatross.
Links
References
BirdLife International. 2003. BirdLife's online World Bird Database the site for bird conservation. Version 2.0. www.birdlife.org. Cambridge, UK BirdLife International. Accessed 6/17/03.
Hasegawa, H. and A.R. DeGange. 1982. The Short-tailed albatross, Diomedea albatrus, its status, distribution, and natural history. American Birds 36:806-814.
Cherel, Y. and N. Klages. 1998. A review of the food of albatrosses. pp. 113-136 in G. Robertson and R. Gales, eds. Albatross Biology and Conservation. Surrey Beatty and Sons, Chipping Norton, Australia.
McDermond, D.K. and K.H. Morgan. 1993. Status and conservation of North Pacific albatrosses. pp. 70-81 in K. Vermeer, K.T. Briggs, K.H. Morgan and D. Siegel-Causey, eds. The status, ecology, and conservation of marine birds of the North Pacific. Canadian Wildlife Service Special Publication, Ottawa.
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ITIS TSN | 554377 |
Status - ESA, U.S. FWS
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E (Wherever found) |
Status - Red List, IUCN
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VU (Global) |
#records (spatial) | 1,610 |
#records (non-spatial) | 0 |
#datasets | 7 |
Year | 1940 - 2013 |
Latitude | 19.07 - 64.33 |
Longitude | -177.16 - 252.50 |
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