Arctic Tern (Sterna Paradisaea)

The Arctic Tern (Sterna Paradisaea) migrates further than any other bird, spending the breeding season in the Arctic and the rest of the year in the Antarctic, spending most of its life when not actively migrating living in the polar summer.
The Arctic Tern is a plunge feeder. It looks more 'bouncy' in flight than the Common Tern. When feeding it alternates between hovering and dipping, before finally plunging. The Arctic Tern feeds, breeds and migrates in large groups. It can be a rather aggressive bird, especially if something enters the breeding colonies. It eats small fish, including sticklebacks, caplins, sprats, herrings and sand-eels. Away from the sea it eats insects and sometimes worms in flooded ground.

The migration of the Arctic Tern is quite remarkable. At some point between late July and early October it leaves its breeding grounds and begins to move south, following the coasts of America, Europe and Africa. Eventually it reaches its 'winter' grounds in the pack-ice of Antarctica, the longest migration possible without flying in circles!

The Arctic Tern is present in quite large numbers in the UK, with 53,000 pairs as of 2000. Its numbers are declining, possibly because of over-fishing of the Sand-Eel population.

In its summer plumage the Arctic Tern has a red beak and short red legs. The wings are pale grey on top and lighter underneath. The body is white underneath and pale grey on top. The cheeks are white, while the top of the head is black. Juveniles and birds in their first winter have a white patch above the beak.

The colouring of the Arctic Tern is very similar to that of the Common Tern. The under parts are a darker shade of grey, and so there is more contrast with the white cheeks. On the wings the Arctic Tern has a dark line along the back of the outer part of the wing, while the Common Tern has a larger black wedge.

The Arctic Tern breeds on shingle or stony beaches on the coast and on river banks and on offshore islands. British birds begin to breed in May. The female lays one or two speckled buff, green or blue-white eggs into a shallow scrape. Both parents incubate the eggs which hatch after 20-24 days. The chicks leave the nest after a few days and hide in nearby rocks or plants. They flight after 21-24 days, and become independent after another two months.

In the breeding season the Arctic Tern lives on-shore, and feeds both inland and in coastal waters. Away from the breeding season it is a true sea bird, rarely coming to land.

Order: Charadriiformes (Gulls, terns, plovers etc)
Family: Sternidae
Genus: Sterna
Species: Paradisaea

Most British birds breed around the coast of Scotland. There is also a breeding population in North Wales and a few around the English coast. They are also found around much of the Irish coast. The Arctic Tern also breeds in the Arctic, North America, Scandinavia and northern Russia.

Physical Details
Length: 33-35cm
Weight: 86-127g
Lifespan: Ringed birds have lived for nearly 30 years.