Scripps's murrelet | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Class: | Aves |
Order: | Charadriiformes |
Family: | Alcidae |
Genus: | Synthliboramphus |
Species: | S. scrippsi |
Binomial name | |
Synthliboramphus scrippsi (Green & Arnold, 1939) | |
Year-round Nonbreeding | |
Synonyms | |
Synthliboramphus hypoleucus scrippsi |
Scripps's murrelet (Synthliboramphus scrippsi) 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. [1]
This species and the Guadalupe murrelet were considered conspecific and were known collectively as Xantus's murrelet until 2012. The two species are now considered distinct based on a lack of evidence of interbreeding at a shared nesting colony on the San Benito Islands, differences in facial pattern and bill shape, and differences in vocalizations and genetics. [2] [3] [4]
This species is a small black and white auk with a small head and thin sharp bill. It resembles the closely related Craveri's murrelet, with which it shares the distinction of being the most southerly living of all the auk species. It breeds on islands in the Channel Islands of California, the largest colonies being on the Coronado Islands and on Santa Barbara Island, and also several islands off Baja California, including Isla Guadalupe. After the breeding season it disperses north at sea, usually to offshore waters, as far as British Columbia.
Scripps's murrelet feeds at sea (but on average not as far from land as Guadalupe murrelet), often in association with large pelagic predatory fish like tuna, on larval fish like anchovies, sardines and Sebastes rockfish. Like all auks it is a wing-propelled diver, chasing down prey under the water with powerful wingbeats. There is some speculation that it may feed cooperatively in pairs, as it is almost always observed in pairs, even during the non-breeding season. It flies well, and can take off without taxiing.
It nests in loose scattered colonies on arid islands, typically in small crevices and caves and under dense bushes. It returns to the colony only at night, laying two eggs which are incubated for about a month. As in other synthliboramphine murrelet species (e.g. the ancient murrelet) the chicks are highly precocial, leaving the nest within two days of hatching and running actively towards the sea, where the parents call to them. Once at sea the family swims to offshore waters.
Little is known about their time at sea due to difficulties in studying them in this habitat. A female shot at Isla Guadalupe at the end of June was moulting its primary remiges (flight feathers) and unable to fly. [5]
By the end of the 20th century, the Xantus's murrelet complex was considered to be among the most endangered species of auk. [6] This has changed since, but not because the present species' status has improved, but because other auks have become rarer.
Scripps's murrelet is mainly threatened by oil spills, as much of its population lives near the busy shipping lanes connecting Los Angeles to other ports. Because a large part of its small population nests in such a small area, a single catastrophic oil spill could have far reaching implications. It is also threatened by introduced species such as rats and feral cats; this threat has been lessened lately by efforts to restore its habitat by removing introduced predators. In 2001 and 2002, Island Conservation, the Channel Islands National Park, California Department of Fish and Game, the U.S. Fish and Wildlife Service, and the National Oceanic and Atmospheric Administration removed invasive rats from Anacapa Island. [7] This effort was paid for by a trust fund from an oil spill settlement.
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.
Northern storm petrels are seabirds in the genus Hydrobates in the family Hydrobatidae, part of the order Procellariiformes. The family was once lumped with the similar austral storm petrels in the combined storm petrels, but have been split, as they were not closely related. 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.
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 common murre or common guillemot is a large auk. It has a circumpolar distribution, occurring in low-Arctic and boreal waters in the North Atlantic and North Pacific. It spends most of its time at sea, only coming to land to breed on rocky cliff shores or islands.
Anacapa Island is a small volcanic island located about 11 miles (18 km) off the coast of Port Hueneme, California, in Ventura County. The island is composed of a series of narrow islets 6 mi (10 km) long, oriented generally east–west and 5 mi (8 km) east of Santa Cruz Island. The three main islets, East, Middle and West Anacapa, are collectively known as The Anacapas by some authors. All three islets have precipitous cliffs, dropping off steeply into the sea.
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.
The Guadalupe murrelet or Xantus'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.
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 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 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.
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.
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.
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.