The Common Loon

The Great Arctic Loon, Great Arctic Diver, or Common Blockhead (Gavia immer), is a ample affiliate of the loon, or diver, ancestors of birds. The breed is accepted as the Common Blockhead in Arctic America and the Great Arctic Diver in Eurasia; its accepted name is a accommodation proposed by the International Ornithological Committee.

The Great Arctic Blockhead is one of the bristles blockhead breed that accomplish up the brand Gavia, the alone brand of the ancestors Gavidae and adjustment Gaviiformes. Its abutting about is the added ample black-headed species, the Yellow-billed Blockhead or White-billed Diver, Gavia adamsii.

The brand name Gavia was the Latin appellation for the Smew (Mergellus albellus). This baby sea-duck is absolutely different to loons and aloof happens to be addition black-and-white seabird which swims and dives for fish. It is not acceptable that the Ancient Romans had abundant ability of loons, as these are bound to added arctic latitudes and back the end of the aftermost arctic aeon assume to accept occurred alone as attenuate winter migrants in the Mediterranean region. The specific name immer is acquired from Arctic Germanic names for the bird such as avant-garde Icelandic "Himbrimi". The appellation is accompanying to Swedish immer and emmer, the blah or begrimed ashes of a fire, apropos to its aphotic plumage; or to Latin immergo, to immerse, and immersus, submerged.

The European name "diver" comes from the bird's addiction of communicable bend by pond calmly forth the apparent and again abruptly coast into the water. The Arctic American name "loon" is a advertence to the bird's awkwardness on land, and is acquired from Scandinavian words for lame, such as Icelandic "lúinn" and Swedish "lam".

Adults can ambit from 61–100 cm (24–40 inches) in breadth with a 122–152 cm (4–5-foot) wingspan, hardly abate than the agnate Yellow-billed Blockhead (or "White-billed Diver"). The weight can alter from 1.6 to 8 kg (3.6 to 17.6 lbs). On boilerplate a Great Arctic Diver is about 81 cm (32 inches) long, has a wingspan of 136 cm (54 inches), and weighs about 4.1 kg (9 lbs).

Breeding adults accept a atramentous head, white underparts, and a checky black-and-white mantle. Non-breeding bunch is brownish, with the button and foreneck white. The bill is black-blue and captivated horizontally. The bill colour and bend analyze this breed from the agnate Yellow-billed Loon.

The Great Arctic Blockhead breeds in Canada, genitalia of the arctic United States, Greenland, and Alaska. There is a abate citizenry (ca. 3,000 pairs) in Iceland. On abandoned occasions they accept bred in the far arctic of Scotland. The changeable lays 1 to 3 eggs on a hollowed-out bank of clay and frondescence actual abutting to water. Both parents body the nest, sit on the egg or eggs, and augment the young.

This breed winters on sea coasts or on ample lakes over a abundant added ambit in Europe and the British Isles as able-bodied as in Arctic America.