Least auklet | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Class: | Aves |
Order: | Charadriiformes |
Family: | Alcidae |
Genus: | Aethia |
Species: | A. pusilla |
Binomial name | |
Aethia pusilla (Pallas, 1811) | |
The least auklet (Aethia pusilla) is a seabird and the smallest species of auk. It is the most abundant seabird in North America, and one of the most abundant in the world, with a population of around nine million birds. They breed on the islands of Alaska and Siberia, and spend the winter close to the edge of the ice sheet [ clarification needed ]. Their largest colonies are on the Aleutian Islands, St. Lawrence Island and Little Diomede Island.
Least auklets feed predominantly on calanoid copepods, particularly those of the genus Neocalanus . They also eat euphausiids, pteropods and other zooplankton species. They hunt for these in stratified waters caused where upwelling and thermoclines cause these prey items to be tightly clumped together. Like all auks they are pursuit divers, using their wings to provide thrust and "fly" under the water. They are voracious predators, consuming 86% of their body weight each day.
Least auklets are highly colonial, nesting in rocky crevices in colonies of up to a million birds. These colonies are often mixed, with other species of auklet nesting with, and competing with the least auklets. While this coexistence with other species may bring the benefits of protection from predators, least auklets are vulnerable to being displaced from their nesting sites by the larger crested auklets. A single egg is laid in the crevice and incubated for a month, after which a semi-precocial black downy chick is hatched. Both parents share incubation duties, as well as brooding and feeding duties. Unlike many auks, which are fed fish carried crosswise in the bill, chicks of the least auklet are fed copepods and other zooplankton from a sublingual pouch, as are other small auklets. The chicks receive no further parental care after they fledge, and can dive to hunt as soon as they leave the nest.
Least auklets are vulnerable to oil spills and introduced species. The introduction of Arctic foxes to many of the Aleutian Islands caused the species to be wiped out on many of those islands, and rats are also a problem on many islands. However, at present they are still a very common species, and are not considered threatened by the IUCN.
The tufted puffin, also known as crested puffin, is a relatively abundant medium-sized pelagic seabird in the auk family (Alcidae) found throughout the North Pacific Ocean. It is one of three species of puffin that make up the genus Fratercula and is easily recognizable by its thick red bill and yellow tufts.
Puffins are any of three species of small alcids (auks) in the bird genus Fratercula. These are pelagic seabirds that feed primarily by diving in the water. They breed in large colonies on coastal cliffs or offshore islands, nesting in crevices among rocks or in burrows in the soil. Two species, the tufted puffin and horned puffin, are found in the North Pacific Ocean, while the Atlantic puffin is found in the North Atlantic Ocean.
An auk or alcid is a bird of the family Alcidae in the order Charadriiformes. The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. The family contains 25 extant or recently extinct species that are divided into 11 genera.
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 Atlantic puffin, also known as the common puffin, is a species of seabird in the auk family. It is the only puffin native to the Atlantic Ocean; two related species, the tufted puffin and the horned puffin are found in the northeastern Pacific. The Atlantic puffin breeds in Russia, Iceland, Ireland, Norway, Greenland, Newfoundland and Labrador, Nova Scotia, and the Faroe Islands, and as far south as Maine in the west and France in the east. It is most commonly found in the Westman Islands, Iceland. Although it has a large population and a wide range, the species has declined rapidly, at least in parts of its range, resulting in it being rated as vulnerable by the IUCN. On land, it has the typical upright stance of an auk. At sea, it swims on the surface and feeds on small fish and crabs, which it catches by diving underwater, using its wings for propulsion.
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 pigeon guillemot is a species of bird in the auk family, Alcidae. One of three species in the genus Cepphus, it is most closely related to the spectacled guillemot. There are five subspecies of the pigeon guillemot; all subspecies, when in breeding plumage, are dark brown with a black iridescent sheen and a distinctive wing patch broken by a brown-black wedge. Its non-breeding plumage has mottled grey and black upperparts and white underparts. The long bill is black, as are the claws. The legs, feet, and inside of the mouth are red. It closely resembles the black guillemot, which is slightly smaller and lacks the dark wing wedge present in the pigeon guillemot.
The horned puffin is an auk found in the North Pacific Ocean, including the coasts of Alaska, Siberia and British Columbia. It is a pelagic seabird that feeds primarily by diving for fish. It nests in colonies, often with other auks.
The parakeet auklet is a small seabird of the North Pacific. Parakeet Auklets used to be placed on its own in the genus Cyclorrhynchus but recent morphological and genetic evidence suggest it should be placed in the genus Aethia, making them closely related to crested auklets and least auklets. It is associated with the boreal waters of Alaska, Kamchatka and Siberia. It breeds on the cliffs, slopes and boulder fields of offshore islands, generally moving south during the winter.
Cassin's auklet is a small, chunky seabird that ranges widely in the North Pacific. It is the only species placed in the genus Ptychoramphus. It nests in small burrows and because of its presence on well studied islands in British Columbia and off California it is one of the better known auks. It is named for the American ornithologist John Cassin.
The rhinoceros auklet is a seabird and a close relative of the puffins. It is the only extant species of the genus Cerorhinca. Given its close relationship with the puffins, the common name rhinoceros puffin has been proposed for the species.
Kittlitz's murrelet is a small alcid found in the waters off Alaska and Eastern Siberia. This near threatened species is, like the closely related marbled murrelet, unusual for seabirds in not being colonial, nesting instead in isolated locations on mountain tops, where the nests were known to Native Americans for many years before skeptical ornithologists described and photographed them. It is a poorly known and little studied species, although concern over its status and that of the closely related marbled murrelet has led to a recent increase in research.
The whiskered auklet is a small seabird of the auk family. It has a more restricted range than other members of its genus, Aethia, living only around the Aleutian Islands and on some islands off Siberia, and breeding on these islands. It is one of the smallest alcids, only the closely related least auklet being smaller. Its name is derived from the long white feathers on its face that are part of its breeding plumage.
The crested auklet is a small seabird of the family Alcidae, distributed throughout the northern Pacific and the Bering Sea. The species feeds by diving in deep waters, eating krill and a variety of small marine animals. It nests in dense colonies of up to 1 million individuals in the Bering Sea and the Sea of Okhotsk. It often breeds in mixed-species colonies with the least auklet, a smaller congener.
The black storm petrel is a small seabird of the storm petrel family Hydrobatidae. It is 23 cm in length, with a wingspan of 46–51 cm.
The fork-tailed storm petrel is a small seabird of the storm petrel family Hydrobatidae. It is the second-most abundant and widespread storm petrel and is the only bird in its family that is bluish-grey in colour.
Aethia is a genus of four small (85–300g) auklets endemic to the North Pacific Ocean, Bering Sea and Sea of Okhotsk and among some of North America's most abundant seabirds. The relationships between the four true auklets remains unclear. Auklets are threatened by invasive species such as Arctic foxes and Norway rats because of their high degree of coloniality and crevice-nesting.
A bird colony is a large congregation of individuals of one or more species of bird that nest or roost in proximity at a particular location. Many kinds of birds are known to congregate in groups of varying size; a congregation of nesting birds is called a breeding colony. Colonial nesting birds include seabirds such as auks and albatrosses; wetland species such as herons; and a few passerines such as weaverbirds, certain blackbirds, and some swallows. A group of birds congregating for rest is called a communal roost. Evidence of colonial nesting has been found in non-neornithine birds (Enantiornithes), in sediments from the Late Cretaceous (Maastrichtian) of Romania.
Austral storm petrels, or southern storm petrels, are seabirds in the family Oceanitidae, part of the order Procellariiformes. These smallest of seabirds feed on planktonic crustaceans and small fish picked from the surface, typically while hovering. Their flight is fluttering and sometimes bat-like.
Seabirds include some of the most threatened taxa anywhere in the world. For example, of extant albatross species, 82% are listed as threatened, endangered, or critically endangered by the International Union for Conservation of Nature. The two leading threats to seabirds are accidental bycatch by commercial fishing operations and introduced mammals on their breeding islands. Mammals are typically brought to remote islands by humans either accidentally as stowaways on ships, or deliberately for hunting, ranching, or biological control of previously introduced species. Introduced mammals have a multitude of negative effects on seabirds including direct and indirect effects. Direct effects include predation and disruption of breeding activities, and indirect effects include habitat transformation due to overgrazing and major shifts in nutrient cycling due to a halting of nutrient subsidies from seabird excrement. There are other invasive species on islands that wreak havoc on native bird populations, but mammals are by far the most commonly introduced species to islands and the most detrimental to breeding seabirds. Despite efforts to remove introduced mammals from these remote islands, invasive mammals are still present on roughly 80% of islands worldwide.