Seabirds
Some seabirds, such as the Black Guillemot and some gulls, are quite sedentary; others, such as most of the terns and auks breeding in the temperate northern hemisphere, move south varying distances in winter. The Arctic Tern has the longest-distance migration of any bird, and sees more daylight than any other, moving from its arctic breeding grounds to the antarctic wintering areas. One Arctic Tern, ringed (banded) as a chick on the Farne Islands off the British east coast, reached Melbourne, Australia in just three months from fledging, a sea journey of over 22,000 km (14,000 miles). Seabirds, of course, have the advantage that they can feed on migration.
The most pelagic species, mainly in the 'tubenose' order Procellariiformes, are great wanderers, and the albatrosses of the southern oceans may circle the globe as they ride the "roaring forties" outside the breeding season. The tubenoses in general spread thinly over large areas of open ocean, but congregate when food becomes available. Many of them are also among the longest-distance migrants; Sooty Shearwaters nesting on the Falkland Islands migrate 14,000 km (9,000 miles) between the breeding colony and the North Atlantic Ocean off Norway, and some Manx Shearwaters do the same journey in reverse. As they are long-lived birds, they may cover enormous distances during their lives; one record-breaking Manx Shearwater is calculated to have flown 8 million km (5 million miles) during its over-50 year lifespan.
Pelagic birding trips attract petrels and other procellarids by tipping "chum", a mixture of fish oil and offal, into the sea. Within minutes, a previously apparently empty ocean is full of petrels, fulmars and shearwaters attracted by the food.
A few seabirds, such as Wilson's Petrel and Great Shearwater, breed in the southern hemisphere and migrate north in the southern winter.
This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.
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