Short-tailed albatross | |
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Scientific classification ![]() | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Procellariiformes |
Family: | Diomedeidae |
Genus: | Phoebastria |
Species: | P. albatrus |
Binomial name | |
Phoebastria albatrus | |
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Synonyms | |
Diomedea albatrus [4] |
The short-tailed albatross or Steller's albatross (Phoebastria albatrus) is a large rare seabird from the North Pacific. Although related to the other North Pacific albatrosses, it also exhibits behavioural and morphological links to the albatrosses of the Southern Ocean. It was described by the German naturalist Peter Simon Pallas from skins collected by Georg Wilhelm Steller (after whom its other common name is derived). Once common, it was brought to the edge of extinction by the trade in feathers, but with protection efforts underway since the 1950s, the species is in the process of recovering with an increasing population trend. Its breeding range, however, remains small. [5] It is divided into two distinct subpopulations, one of which breeds on Tori-shima in the Izu islands south of Japan, and the other primarily on the Senkaku Islands in the East China Sea.
The short-tailed albatross is a medium-sized albatross, with a wingspan of 215 to 230 cm (85–91 in), [6] a length of 84 to 94 cm (33–37 in) [7] [8] and a body weight that can be 4.3 to 8.5 kg (9.5–18.7 lb). Among standard measurements, the bill is 12.7–15.2 cm (5.0–6.0 in) long, the tail is 14–15.2 cm (5.5–6.0 in) long, the tarsus around 10 cm (3.9 in) and the wing chord 51 cm (20 in). [9] Its plumage as an adult is overall white with black flight feathers, some coverts, as well as a black terminal bar on its tail. It has a yellow-stained nape and crown. Its bill is large and pink; however, older birds will gain a blue tip. The juveniles are an all-over brown colour, and they will whiten as they mature, [10] in about 10 to 20 years. [11] [12] It can be distinguished from the other two species of albatross in its range, the Laysan albatross and the black-footed albatross by its larger size and its pink bill (with a bluish tip), as well as details of its plumage. Contrary to its name its tail is no shorter than that of the Laysan or black-footed, and is actually longer than that of the other member of the genus Phoebastria , the waved albatross.
Short-tailed albatrosses now nest on four islands, with the majority of birds nesting on Tori-shima, and almost all of the rest on Minami-kojima in the Senkaku Islands. A female-female pair began nesting on Kure in the late 2000s, but to date they have not produced a viable egg. A chick hatched on 14 January 2011 on Midway. Both Midway and Kure are in the Northwestern Hawaiian Islands. [13] In 2012 a pair began incubating an egg on Muko-jima, in the Bonin Islands, Japan. [14] During non-breeding season they range across the North Pacific, with the males and juveniles gathering in the Bering Sea, and the females feeding off the coast of Japan and eastern Russia. [10] They can also be found as far east as California. In fact, the short-tailed albatross is seen on a number of the United States' state endangered species lists including Washington. [15]
The species has been extirpated as a breeder from Kita-no-shima, Enewetak Atoll, Kobishi, and the Bonin Islands (Nishino Shima, Yomejima, and (until recently) Mukojima). [4] It also formerly bred on Bermuda during the Pleistocene. [16]
Short-tailed albatrosses are a type of albatross that belong to the family Diomedeidae, 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. The bills of Procellariiformes are also unique in that they are split into between seven and nine horny plates. Finally, 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. [17] They also have a salt gland which is situated above the nasal passage helping desalinate their bodies, as an adaptation to the high amount of ocean water they imbibe. It excretes a high saline solution from their nose. [18]
The species is divided into two major clades/populations, one of which exclusively breeds on Tori-shima, and the other breeds primarily on the Senkaku Islands with a small number on Tori-shima. These two populations are genetically, morphologically, and behaviourally distinct, preferring to mate with their own kind, and as such it has been argued by some authors that they should be classified as two separate species. [19] [20] [21]
The short-tailed albatross feeds mainly on squid, but will follow ships for their discarded offal. [10]
This albatross historically preferred to nest on large open areas near stands of the grass, Miscanthus sinensis . [10]
The short-tailed albatross usually first breeds at 10 years of age. [22]
The short-tailed albatross lays a clutch of one egg that is dirty white, with red spots, mainly at the blunt end of the egg. It usually measures 116 by 74 millimetres (4.6 in × 2.9 in). The egg is incubated for around 65 days. Both sexes incubate the eggs. [22]
Breeding location | Population | Trend |
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Tori-shima (Izu Islands) | 3540 | up from 25 since 1954 |
Minami-kojima and Kita-kojima | 650 | Unknown |
Ogasawara Islands | 10 | Unknown |
Total | 4200 |
The IUCN classifies this species as vulnerable, [1] with an occurrence range of 34,800,000 km2 (13,400,000 sq mi) and a breeding range of 9 km2 (3.5 sq mi).
The short-tailed albatross came perilously close to extinction. They were hunted on an almost industrial scale for their feathers in the later half of the 19th century, with some estimates claiming upward of 10 million birds hunted. By the 1930s the only population left was on Torishima, between 1927 and until 1933 hunting continued when the Japanese government declared the ban of hunting to save the species, after which the albatrosses stopped breeding on the island. At this point the species was assumed to be extinct and research became impossible with the outbreak of World War II. On 1949 an American researcher arriving on this island declared the species to be extinct, but an estimated 50 individuals, most likely juveniles, survived at sea (all albatross species take a long time to reach sexual maturity and will not return to their natal colony for many years). After the return of the birds they were more carefully protected, and the first egg was laid by the returning birds in 1954. Varieties of albatross decoys were placed around on the island after it was discovered that like other albatross species, this species also were enticed to breed if placed in a group.[ citation needed ]
Between 2008 and 2012, the Ministry of the Environment relocated 70 albatross chicks from Tori-shima to Mukojima to breed them artificially. [24]
Today, longline fisheries and volcanic eruptions on Tori-shima are the largest threats; however, introduced predators, environmental contaminants, soil instability, and extreme weather are also threats.
There are many measures underway to protect this species. Japan, Canada, and the United States list this bird as a protected species. Tori-shima is a National Wildlife Protection Area, and native plant species are being transplanted to assist in nesting. Also, most commercial longline fisheries use bycatch mitigation devices. [10]
In 2017, a wild short-tailed albatross that had been born to an artificially-raised mother was confirmed to have returned to the Bonin Islands. This marks the first time a wild bird had returned to the islands in roughly 80 years. The bird was believed to have left its nest on Nakōdo-jima and flown north to Mukojima. [24]
In Japanese tradition the short-tailed albatross is known as ahodori (阿呆鳥, idiot bird), due to its insular breeding habits making it trusting towards terrestrial predators such as humans. [25] [26]
Procellariiformes is an order of seabirds that comprises four families: the albatrosses, the petrels and shearwaters, and two families of storm petrels. Formerly called Tubinares and still called tubenoses in English, procellariiforms are often referred to collectively as the petrels, a term that has been applied to all members of the order, or more commonly all the families except the albatrosses. They are almost exclusively pelagic, and have a cosmopolitan distribution across the world's oceans, with the highest diversity being around New Zealand.
Seabirds are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous period, and modern seabird families emerged in the Paleogene.
The black-browed albatross, also known as the black-browed mollymawk, is a large seabird of the albatross family Diomedeidae; it is the most widespread and common member of its family.
The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the diving petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes, which also includes the albatrosses and the storm petrels.
The waved albatross, also known as Galapagos albatross, is one of three species of the family Diomedeidae that occur in the tropics. When they forage, they follow a straight path to a single site off the coast of Peru, about 1,000 km (620 mi) to the east. During the non-breeding season, these birds reside primarily on the Ecuadorian and Peruvian coasts.
The Chatham albatross, also known as the Chatham mollymawk or Chatham Island mollymawk, is a medium-sized black-and-white albatross which breeds only on The Pyramid, a large rock stack in the Chatham Islands, New Zealand. It is sometimes treated as a subspecies of the shy albatross Thalassarche cauta. It is the smallest of the shy albatross group.
The black-footed albatross is a large seabird of the albatross family Diomedeidae from the North Pacific. All but 2.5% of the population is found among the Northwestern Hawaiian Islands. It is one of three species of albatross that range in the northern hemisphere, nesting on isolated tropical islands. Unlike many albatrosses, it is dark plumaged.
The Laysan albatross is a large seabird that ranges across the North Pacific. The Northwestern Hawaiian Islands are home to 99.7% of the population. This small gull-like albatross is the second-most common seabird in the Hawaiian Islands, with an estimated population of 1.18 million birds, and is currently expanding its range to new islands. The Laysan albatross was first described as Diomedea immutabilis by Lionel Walter Rothschild, in 1893, on the basis of a specimen from Laysan Island.
The sooty albatross, dark-mantled sooty albatross or dark-mantled albatross,, is a species of bird in the albatross family. They breed on sub-Antarctic islands and range at sea across the Southern Ocean from South America to Australia.
The North Pacific albatrosses are large seabirds from the genus Phoebastria in the albatross family. They are the most tropical of the albatrosses, with two species nesting in the Northwestern Hawaiian Islands, one on sub-tropical islands south of Japan, and one nesting on the equator.
The Indian yellow-nosed albatross is a member of the albatross family, and is the smallest of the mollymawks. In 2004, BirdLife International split this species from the Atlantic yellow-nosed albatross; however Clements has not split it yet, and the SACC has not either, but recognises the need for a proposal.
The northern royal albatross or toroa,, is a large seabird in the albatross family. It was split from the closely related southern royal albatross as recently as 1998, though not all scientists support that conclusion and some consider both of them to be subspecies of the royal albatross.
The blue petrel is a small seabird in the shearwater and petrel family, Procellariidae. This small petrel is the only member of the genus Halobaena, but is closely allied to the prions. It is distributed across the Southern Ocean but breeds at a few island sites, all close to the Antarctic Convergence zone.
The southern royal albatross or toroa, is a large seabird from the albatross family. At an average wingspan of above 3 m (9.8 ft), it is one of the two largest species of albatross, together with the wandering albatross. Recent studies indicate that the southern royal albatross may, on average, be somewhat larger than the wandering albatross in mass and have a similar wingspan, although other sources indicate roughly similar size for the two species and the wandering species may have a larger average wingspan in some colonies.
The Tristan albatross is a large seabird from the albatross family. One of the great albatrosses of the genus Diomedea, it was only widely recognised as a full species in 1998.
Albatrosses, of the biological family Diomedeidae, are large seabirds related to the procellariids, storm petrels, and diving petrels in the order Procellariiformes. They range widely in the Southern Ocean and the North Pacific. They are absent from the North Atlantic, although fossil remains show they once occurred there and occasional vagrants are found. Albatrosses are among the largest of flying birds, and species of the genus Diomedea have the longest wingspans of any extant birds, reaching up to 3.7 m (12 ft). The albatrosses are usually regarded as falling into four genera, but disagreement exists over the number of species.
The broad-billed prion is a small pelagic seabird in the shearwater and petrel family, Procellariidae. It is the largest prion, with grey upperparts plumage, and white underparts. The sexes are alike. It ranges from the southeast Atlantic to New Zealand mainly near the Antarctic Convergence. In the south Atlantic it breeds on Tristan da Cunha and Gough Island; in the south Pacific it breeds on islands off the south coast of South Island, New Zealand and on the Chatham Islands. It has many other names that have been used such as blue-billed dove-petrel, broad-billed dove-petrel, long-billed prion, common prion, icebird, and whalebird.
Tori-shima 'Bird Island', or Izu-Torishima 'Bird Island of Izu Province') is an uninhabited Japanese island in the Pacific Ocean. The volcanic island is part of the Izu Islands.