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 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 razorbill, razor-billed auk, or lesser auk is a North Atlantic colonial seabird and the only extant member of the genus Alca of the family Alcidae, the auks. It is the closest living relative of the extinct great auk.
The ancient murrelet is a bird in the auk family. The English term "murrelet" is a diminutive of "murre", a word of uncertain origins, but which may imitate the call of the common guillemot. Ancient murrelets are called "ancient" because they have grey on the back like a shawl, as worn by the elderly.
The marbled murrelet is a small seabird from the North Pacific. It is a member of the family Alcidae, which includes auklets, guillemots, murres and puffins. It nests in old-growth forests or on the ground at higher latitudes where trees cannot grow. The marbled murrelet has declined in number since humans began logging its nest trees in the latter half of the 19th century. The decline of the marbled murrelet and its association with old-growth forests, at least in the southern part of its range, have made it a flagship species in the forest preservation movement.
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 long-billed murrelet is a small seabird from the North Pacific. The genus name Brachyramphus is from Ancient Greek brakhus, "short", and rhamphos, "bill". The species name perdix is Latin for "partridge" Pallas described this auk as Magnitudine Perdicis. "Murrelet" is a diminutive of "murre", a word of uncertain origins, but which may imitate the call of the common guillemot.
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 Guadalupe storm petrel is a small seabird of the storm petrel family Hydrobatidae. It bred only on Guadalupe Island off Baja California, Mexico, and presumably ranged throughout the region. It has been assessed as Critically Endangered or possibly extinct.
The Japanese murrelet or crested murrelet is a small seabird in the auk family that occurs along the remote rocky coasts and in the offshore waters of Japan, and may also be found after the breeding season as far as Sakhalin to the north and in particular off South Korea. With a small and declining population, estimated as of 2017 to total 2,500–10,000 individuals, it is the rarest alcid, and the most at risk of extinction.
The Guadalupe junco is a small bird in the New World sparrow family that is endemic to Guadalupe Island off the western coast of Baja California, Mexico. Many taxonomic authorities classified it in 2008 as a subspecies of the dark-eyed junco. In 2016, it was re-classified as a full species.
The black-vented shearwater is a species of seabird. The bird is 30–38 cm in length with a 76–89 cm wingspan. Formerly considered a subspecies of the Manx shearwater, its actual taxonomic relationships are unresolved.
Craveri's murrelet is a small seabird which breeds on offshore islands in both the Pacific Ocean and the Gulf of California off the Baja peninsula of Mexico. It also wanders fairly regularly as far as central California in the US, primarily during post-breeding dispersal. It is threatened by predators introduced to its breeding colonies, by oil spills, and by tanker traffic. Increasing tourism development and commercial fishing fleets also further threaten the species. With an estimated population of 6,000-10,000 breeding pairs, its population is listed as vulnerable.
Brachyramphus is a small genus of seabirds from the North Pacific. Brachyramphus is from Ancient Greek brakhus, "short", and rhamphos, "bill". In English the species are named as "murrelets"; this is a diminutive of "murre", a word of uncertain origins, but which may imitate the call of the common guillemot.
Synthliboramphus is a small genus of seabirds in the auk family from the North Pacific. The genus name Synthliboramphus is from Ancient Greek sunthlibo, "to compress", and rhamphos, "bill". The English name "Murrelet" is a diminutive of "murre", a word of uncertain origins, but which may imitate the call of the common guillemot.
Scripps's murrelet is a small seabird found in the California Current system in the Pacific Ocean. This auk breeds on islands off California and Mexico. It is threatened by predators introduced to its breeding colonies and by oil spills.
Xantus's murrelet, native to the California Current system, has been split into two species:
Townsend's storm petrel is a species of seabird in the family Hydrobatidae. It breeds in the summer on rocks and islets of Guadalupe Island off the western coast of Mexico. It ranges in the Eastern Pacific Ocean north to southern California in the United States and south to 10°N latitude. It used to be considered a subspecies of the Leach's storm petrel. It was formerly defined in the genus Oceanodroma before that genus was synonymized with Hydrobates.
