Yellow-billed loon | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Gaviiformes |
Family: | Gaviidae |
Genus: | Gavia |
Species: | G. adamsii |
Binomial name | |
Gavia adamsii (Gray, 1859) | |
Range of G. adamsii Breeding range Wintering range |
The yellow-billed loon (Gavia adamsii), also known as the white-billed diver, is the largest member of the loon or diver family. Breeding adults have a black head, white underparts and chequered black-and-white mantle. Non-breeding plumage is drabber with the chin and foreneck white. Its main distinguishing feature is the long straw-yellow bill which, because the culmen is straight, appears slightly uptilted.
It breeds in the Arctic and winters mainly at sea along the coasts of the northern Pacific Ocean and northwestern Norway; it also sometimes overwinters on large inland lakes. It occasionally strays well south of its normal wintering range, and has been recorded as a vagrant in more than 22 countries. This species, like all divers, is a specialist fish-eater, catching its prey underwater. Its call is an eerie wailing, lower pitched than the common loon.
First described by English zoologist George Robert Gray in 1859 based on a specimen collected in Alaska, the yellow-billed loon is a monotypic species, with no subspecies despite its large Holarctic range. [2] It is closely related to the common loon, which it strongly resembles in plumage and behaviour; some taxonomists consider the two species to be allopatric forms of the same superspecies. Both are thought to have evolved from a population of black-throated loons which colonized the Nearctic and were subsequently cut off from other populations. [3]
The genus name Gavia comes from the Latin for "sea mew", as used by ancient Roman naturalist Pliny the Elder. The specific epithet adamsii honours Edward Adams, a British naval surgeon and naturalist who sketched and collected numerous species, including this one, [4] on several trips to the Arctic. [5] The word "loon" is thought to have derived from the Swedish lom, the Old Norse or Icelandic lómr, or the Old Dutch loen, all of which mean "lame" or "clumsy", and is a probable reference to the difficulty that all loons have in moving about on land. [6] "Diver" refers to the family's underwater method of hunting for prey, while "yellow-billed" and "white-billed" are references to the bird's distinctively pale bill. [5]
With a length of 76 to 97 cm (30 to 38 in), a wingspan of 135 to 160 cm (53 to 63 in), and a weight ranging from 4 to 6.4 kg (8.8 to 14.1 lb), the yellow-billed loon is the largest member of the loon (diver) family. [2] [7] [8] The adult is primarily black and white in breeding plumage, with a purple gloss on its head and neck. [9]
The yellow-billed loon is an Arctic species, breeding primarily along the coasts of the Arctic Ocean as far north as 78° N and wintering on sheltered coastal waters of the northern Pacific Ocean and the northwestern coast of Norway. [2] It has been recorded as a breeding bird in Russia, Canada and the United States. [1] Though it winters primarily to the north of 50° N, its winter range extends south to 35° N off the coast of Japan, [2] and it has been recorded as a vagrant in more than 20 countries, [1] including some as far south as Mexico [10] and Spain. [1]
Like other loons, it forms long-lasting pairs. Though it prefers freshwater pools or lakes in the tundra, the yellow-billed loon will also breed along rivers, estuaries or the coast in low-lying areas of the Arctic; in general, it avoids forested areas. Breeding typically starts in early June, though it is dependent on the timing of the spring thaw. Like all members of its family, the yellow-billed loon builds a nest of plant material very close to the edge of the water. Copulation takes place on land, without any specific courtship. The pair defends its large territory intensively against intruders, but may later in the breeding season gang up with other birds on good fishing spots. [2]
The female lays two eggs measuring 89 by 55 millimetres (3.5 by 2.2 in). The eggs are strongly oval, and are a light purple-brown with darker blotches interspersed. This colour camouflages with the soil and vegetation that this bird nests near. Most of the time, however, the egg is not visible due to incubation, which takes around 27 to 29 days. [11]
The yellow-billed loon is a specialist fish eater, yet it also takes crustaceans, molluscs and annelids, [2] especially for its young. [11] It dives in pursuit of prey, which is caught underwater. [2] Probably as a way to avoid spreading parasites, it defecates ashore, in the breeding lake.
In 2010, the International Union for the Conservation of Nature (IUCN) changed the status of the yellow-billed loon from Least Concern to Near Threatened, as the species appears to be in a "moderately rapid" population decline. An unsustainable level of subsistence harvesting by indigenous peoples was specifically named as the main threat. [1]
The yellow-billed loon is one of the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies; [12] in the Americas, it is protected by the Migratory Bird Treaty Act of 1918. [13]
The yellow-billed loon is especially vulnerable because of its low fecundity, and face many threats related to their habitat. They need to live in areas with large, deep lakes and these environments are threatened due to high rates of human interaction, such as oil drilling, and the warming climate of their natural habitats. They often nest near oil drilling equipment posing a litany of issues regarding injury and exposure to crude oil. The warming climate causes them to leave their nests in search of cooler areas, leaving their nests, eggs, and young exposed to predation. They are also very territorial birds, and often face injuries that can result in death from fighting other organisms. [14]
Loons or divers are a group of aquatic birds found in much of North America and northern Eurasia. All living species of loons are members of the genus Gavia, family Gaviidae and order Gaviiformes.
The common loon or great northern diver is a large member of the loon, or diver, family of birds. Breeding adults have a plumage that includes a broad black head and neck with a greenish, purplish, or bluish sheen, blackish or blackish-grey upperparts, and pure white underparts except some black on the undertail coverts and vent. Non-breeding adults are brownish with a dark neck and head marked with dark grey-brown. Their upperparts are dark brownish-grey with an unclear pattern of squares on the shoulders, and the underparts, lower face, chin, and throat are whitish. The sexes look alike, though males are significantly heavier than females. During the breeding season, loons live on lakes and other waterways in Canada; the northern United States ; and southern parts of Greenland and Iceland. Small numbers breed on Svalbard and sporadically elsewhere in Arctic Eurasia. Common loons winter on both coasts of the US as far south as Mexico, and on the Atlantic coast of Europe.
The black-throated loon, also known as the Arctic loon and the black-throated diver, is a migratory aquatic bird found in the northern hemisphere, primarily breeding in freshwater lakes in northern Europe and Asia. It winters along sheltered, ice-free coasts of the north-east Atlantic Ocean and the eastern and western Pacific Ocean. This loon was first described by Carl Linnaeus in 1758 and has two subspecies. It was previously considered to be the same species as the Pacific loon, of which it is traditionally considered to be a sister species, although this is debated. In a study that used mitochondrial and nuclear intron DNA, the black-throated loon was found to be sister to a clade consisting of the Pacific loon and two sister species, the common loon and the yellow-billed loon.
The Pacific loon or Pacific diver, is a medium-sized member of the loon, or diver, family.
The red-throated loon or red-throated diver is a migratory aquatic bird found in the northern hemisphere. The most widely distributed member of the loon or diver family, it breeds primarily in Arctic regions, and winters in northern coastal waters. Ranging from 55 to 67 centimetres in length, the red-throated loon is the smallest and lightest of the world's loons. In winter, it is a nondescript bird, greyish above fading to white below. During the breeding season, it acquires the distinctive reddish throat patch which is the basis for its common name. Fish form the bulk of its diet, though amphibians, invertebrates, and plant material are sometimes eaten as well. A monogamous species, red-throated loons form long-term pair bonds. Both members of the pair help to build the nest, incubate the eggs, and feed the hatched young.
The greater white-fronted goose is a species of goose that is closely related to the smaller lesser white-fronted goose. The greater white-fronted goose is migratory, breeding in northern Canada, Alaska, Greenland and Russia, and winters farther south in North America, Europe and Asia. It is named for the patch of white feathers bordering the base of its bill: albifrons comes from the Latin albus "white" and frons "forehead". In the United Kingdom and Ireland, it has been known as the white-fronted goose; in North America it is known as the greater white-fronted goose, and this name is also increasingly adopted internationally. Even more distinctive are the salt-and-pepper markings on the breast of adult birds, which is why the goose is colloquially called the "specklebelly" in North America.
Terns are seabirds in the family Laridae that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated as a subgroup of the family Laridae which includes gulls and skimmers and consists of eleven genera. They are slender, lightly built birds with long, forked tails, narrow wings, long bills, and relatively short legs. Most species are pale grey above and white below, with a contrasting black cap to the head, but the marsh terns, the Inca tern, and some noddies have dark plumage for at least part of the year. The sexes are identical in appearance, but young birds are readily distinguishable from adults. Terns have a non-breeding plumage, which usually involves a white forehead and much-reduced black cap.
The little grebe, also known as dabchick, is a member of the grebe family of water birds. The genus name is from Ancient Greek takhus "fast" and bapto "to sink under". The specific ruficollis is from Latin rufus "red" and Modern Latin -collis, "-necked", itself derived from Latin collum "neck".
The tundra swan is a small swan of the Holarctic. The two taxa within it are usually regarded as conspecific, but are also sometimes split into two species: Bewick's swan of the Palaearctic and the whistling swan proper of the Nearctic. Birds from eastern Russia are sometimes separated as the subspecies C. c. jankowskii, but this is not widely accepted as distinct, with most authors including them in C. c. bewickii. Tundra swans are sometimes separated in the subgenus Olor together with the other Arctic swan species.
The common tern is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migratory, wintering in coastal tropical and subtropical regions. Breeding adults have light grey upperparts, white to very light grey underparts, a black cap, orange-red legs, and a narrow pointed bill. Depending on the subspecies, the bill may be mostly red with a black tip or all black. There are several similar species, including the partly sympatric Arctic tern, which can be separated on plumage details, leg and bill colour, or vocalisations.
The dunlin is a small wader, formerly sometimes separated with the other "stints" in the genus Erolia. The English name is a dialect form of "dunling", first recorded in 1531–1532. It derives from dun, "dull brown", with the suffix -ling, meaning a person or thing with the given quality.
The little stint is a very small wader. It breeds in arctic Europe and Asia, and is a long-distance migrant, wintering south to Africa and south Asia. It occasionally is a vagrant to North America and to Australia. The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds. The specific minuta is Latin for "small.
The grey plover or black-bellied plover is a large plover breeding in Arctic regions. It is a long-distance migrant, with a nearly worldwide coastal distribution when not breeding.
The great white pelican also known as the eastern white pelican, rosy pelican or simply white pelican is a bird in the pelican family. It breeds from southeastern Europe through Asia and Africa, in swamps and shallow lakes.
The red knot or just knot is a medium-sized shorebird which breeds in tundra and the Arctic Cordillera in the far north of Canada, Europe, and Russia. It is a large member of the Calidris sandpipers, second only to the great knot. Six subspecies are recognised.
The king eider is a large sea duck that breeds along Northern Hemisphere Arctic coasts of northeast Europe, North America and Asia. The birds spend most of the year in coastal marine ecosystems at high latitudes, and migrate to Arctic tundra to breed in June and July. They lay four to seven eggs in a scrape on the ground lined with grass and down.
The Sandwich tern is a tern in the family Laridae. It is very closely related to the lesser crested tern, Chinese crested tern, Cabot's tern, and elegant tern and has been known to interbreed with the lesser crested. It breeds in the Palearctic from Europe to the Caspian Sea and winters in South Africa, India, and Sri Lanka.
The lesser crested tern is a tern in the family Laridae.
Forster's tern is a tern in the family Laridae. The genus name Sterna is derived from Old English "stearn", "tern", and forsteri commemorates the naturalist Johann Reinhold Forster.
The Aleutian tern is a migratory bird living in the subarctic region of the globe most of the year. It is frequently associated with the Arctic tern, which it closely resembles. While both species have a black cap, the Aleutian tern may be distinguished by its white forehead. During breeding season, the Arctic terns have bright red bills, feet, and legs while those of the Aleutian terns are black.
Sjölander, Sverre. The reproductive Behavior of the Yellow-billed Loon, Gavia adamsii. (With G. Ågren). The Condor 78:454-463. 1976.