Our Beautiful World

Loons, Gaviidae 




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Pacific Diver, Gavia pacifica, Belyaka Neset.


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Yellow-billed Loon, Gavia adamsii, Belyaka Neset



Common Loon, Gavia immer


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Red-throated Loon, Gavia stellata, Belyaka Neset.



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Red-throated loon (Gavia stellata), Belyaka Spit.

The calls of Chukotka's four loon species are among the most beautiful sounds of the tundra.

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Yellow-billed loons (G. adamsii), Belyaka Spit


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Pacific loons, Gavia. pacifica, Belyaka Spit.

Gaviiformes

Gaviidae Loon family

Gavia stellata, Red-throated Loon
Gavia arctica, Arctic Loon
Gavia pacifica, Pacific Loon
Gavia immer, Great Northern Loon
Gavia adamsii, Yellow-billed Loon


The loons (North America) or divers (UK/Ireland) are a group of aquatic birds found in many parts of North America and northern Eurasia (Europe, Asia and debatably Africa). All living species of loons are members of the genus, Gavia, family.

Loons are excellent swimmers, using their feet to propel themselves above and under water while their wings provide assistance. Because their feet are far back on the body, loons are poorly adapted to moving on land, and usually avoid going onto land, except when nesting.

All loons are decent fliers, though the larger species have some difficulty taking off and thus must swim into the wind to pick up enough velocity to become airborne. Only the Red-throated Diver, Gavia stellata, can take off from land. Once airborne, their considerable stamina allows them to migrate long distances southwards in winter, where they reside in coastal waters.
Loons can live as long as 30 years.

Loons find their prey by sight. They eat mainly fish, supplemented with amphibians, crustaceans and similar mid-sized aquatic fauna. Specifically, they have been noted to feed on crayfish, frogs, snails, salamanders and leeches. They prefer clear lakes because they can more easily see their prey through the water. The loon uses its pointy bill to stab or grasp prey.
They eat vertebrate prey headfirst to facilitate swallowing, and swallow all their prey whole.



Red-throated Loon,
Gavia stellata



An adult Red-throated Loon in breeding plumage swimming in Iceland.
Photo: Ómar Runólfsson, http://en.wikipedia.org/wiki/File:Gavia_stellata_-Iceland_-swimming-8.jpg

The Red-throated Loon or Red-throated Diver, Gavia stellata, is a migratory aquatic bird found in the northern
hemisphere. It breeds primarily in Arctic regions, and winters in northern coastal waters. It is the most widely
distributed member of the loon or diver family. Ranging from 55–67 centimetres (22–26 in) 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, the Red-throated Loon forms long-term pair bonds.
Both members of the pair help to build the nest, incubate the eggs (generally two per clutch) and feed the
hatched young.

The Red-throated Loon has a large global population and a significant global range, though some populations are declining. Oil spills, habitat degradation, pollution and fishing nets are among the major threats this species faces. Natural predators—including various gull species, and both Red foxes and Arctic Foxes, will take eggs and young. The species is protected by a number of international treaties.
Source: http://en.wikipedia.org/wiki/Red-throated_Loon



Black-throated Loon,
Gavia arctica



Arctic Loon Gavia arctica on nest
http://digitalrepository.fws.gov/cdm4/item_viewer.php?CISOROOT=/natdiglib&CISOPTR=744&CISOBOX=1&REC=4

The Black-throated Loon, Gavia arctica, is a migratory aquatic bird found in the northern hemisphere.
The species is known as an Arctic Loon in North America and the Black-throated Diver in Eurasia, its current
name is a compromise proposed by the International Ornithological Committee.

It breeds in Eurasia and occasionally in western Alaska. It winters at sea, as well as on large lakes over a much wider range.

Breeding adults are 58 to 77 cm in length with a 100 to 130 cm wingspan, shaped like a smaller, sleeker version
of the Great Northern Diver. Body mass is reportedly from 2–3.4 kg. They have a grey head, black throat,
white underparts and chequered black-and-white mantle. Non-breeding plumage is drabber with the chin and
foreneck white. Its bill is grey or whitish and dagger-shaped. In all plumages a white flank patch distinguishes
this species from all other divers including the otherwise almost identical Pacific Diver.

This species, like all divers, is a specialist fish-eater, catching its prey underwater. It flies with neck outstretched.
It feeds on fish, insects, crustaceans and amphibians.

The calls include a yodelling high-pitched wail and harsh growls, similar but lower pitched than Pacific Loon.
Source: http://en.wikipedia.org/wiki/Black-throated_Loon


Pacific Loon,
Gavia pacifica



Pacific Loon, Gavia pacifica
Photo: Tim Bowman, USFWS


The Pacific Loon or Pacific Diver, Gavia pacifica, is a medium-sized member of the loon, or diver, family.
It breeds on deep lakes in the tundra region of Alaska and northern Canada as far east as Baffin Island, and in Russia east of the Lena River.

Unlike other loons/divers, this bird may migrate in flocks. It winters at sea, mainly on the Pacific coast, or on large lakes over a much wider range, including China, Japan, North Korea, South Korea, USA and Mexico.
It has occurred as a vagrant to Greenland, Hong Kong, Great Britain, Spain, and Finland.

Breeding adults are like a smaller sleeker version of Great Northern Diver/Common Loon.
They measure 58–74 cm in length, 110–128 cm in wingspan and weigh 1–2.5 kg. They have a grey head, black throat, white underparts and chequered black-and-white mantle. Non-breeding plumage is drabber with the chin and foreneck white. Its bill is grey or whitish and dagger-shaped. In all plumages, lack of a white flank patch distinguishes this species from the otherwise very similar Black-throated Diver/Arctic Loon.

This species, like all divers/loons, is a specialist fish-eater, catching its prey underwater.
It flies with neck outstretched.
The call is a yodelling high-pitched wailing, as well as harsh growls and barks.
Source: http://en.wikipedia.org/wiki/Pacific_Loon


Great Northern Loon ,
Gavia immer




A Great Northern Loon in Minocqua, Wisconsin, USA.
Photo: John Picken, http://en.wikipedia.org/wiki/File:Gavia_immer_-Minocqua,_Wisconsin,_USA_-swimming-8.jpg

The Great Northern Loon, Gavia immer, is a large member of the loon, or diver, family of birds.
The species is known as the Common Loon in North America and the Great Northern Diver in Eurasia;
its current name is a compromise proposed by the International Ornithological Committee.

Adults can range from 61 to 100 cm in length with a 122–152 cm wingspan, slightly smaller than the similar
Yellow-billed Loon (or "White-billed Diver"). The weight can vary from 1.6 to 8 kg. On average a
Great Northern Loon is about 81 cm long, has a wingspan of 136 cm , and weighs about 4.1 kg .

Breeding adults have a black head, white underparts, and a checkered black-and-white mantle. Non-breeding plumage is brownish, with the chin and foreneck white. The bill is black-blue and held horizontally.
The bill colour and angle distinguish this species from the similar Yellow-billed Loon.

The Great Northern Loon breeds in Canada, parts of the northern United States, Greenland, and Alaska.
There is a smaller population (ca. 3,000 pairs) in Iceland. On isolated occasions they have bred in the far north
of Scotland. The female lays 1 to 3 eggs on a hollowed-out mound of dirt and vegetation very close to water.
Both parents build the nest, sit on the egg or eggs, and feed the young.

This species winters on sea coasts or on large lakes over a much wider range in Europe and the British Isles
as well as in North America.

Source: http://en.wikipedia.org/wiki/Great_Northern_Loon


Yellow-billed Loon, Gavia adamsii



Juvenile Yellow-billed Loon, a rare visitor to the California coast
Photo: Len Blumin, http://en.wikipedia.org/wiki/File:Gavia_adamsii.jpg

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. The main distinguishing feature from Great Northern Loon is the longer 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 Great Northern Diver.



Yellow-billed Loon Gavia adamsii off Hwajin Po, January 5th 2009,
Photo © Thomas Langenberg, http://www.birdskorea.org/

With a length of 76 to 97 cm, a wingspan of 135 to 160 cm, and a weight ranging from 4 to 6.4 kg, so
the Yellow-billed Loon is the largest member of the loon (diver) family. The adult is primarily black and white
in breeding plumage, with a purple gloss on its head and neck.

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. It has been recorded as a breeding bird in Russia, Canada and the United States. Though it winters primarily to the north of 50° N, its winter range extends south to 35° N off the coast of Japan, and it has been recorded as a vagrant in more than 20 countries, including some as far south as Mexico and Spain.

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. The female lays two eggs.

The Yellow-billed Loon is a specialist fish eater, though it also takes crustaceans, molluscs and annelids.
It dives in pursuit of prey, which is caught underwater.
Source: http://en.wikipedia.org/wiki/Yellow-billed_Loon


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