Sooty Shearwater
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| Sooty Shearwater Conservation status: See text | ||||||||||||||
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| Missing image Puffinus_griseus.png Sooty Shearwater | ||||||||||||||
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| Puffinus griseus Gmelin, 1789 |
The Sooty Shearwater (Puffinus griseus) is a medium-large shearwater in the seabird family Procellariidae. In New Zealand is also known by the names Muttonbird and Tītī (Maori name).
Sooty Shearwaters breed on small islands in the south Pacific and south Atlantic Oceans, mainly around New Zealand, the Falkland Islands and Tierra del Fuego.
They are spectacular long-distance migrants, following a circular route, travelling north up the western side of the Pacific and Atlantic Oceans at the end of the nesting season in March-May, reaching subarctic waters in June-July where they cross from west to east, then returning south down the eastern side of the oceans in September-October, reaching to the breeding colonies in November.
In the Atlantic Ocean, they cover distances in excess of 14,000 km (9,000 miles) from their breeding colony on the Falkland Islands (52°S 60°W) north to 60°-70°N in the North Atlantic Ocean off north Norway; distances covered in the Pacific are similar, though the Pacific Ocean colonies are not quite so far south, at 35°-50°S off New Zealand, and moving north to the Aleutian Islands.
In Britain, they move south in late August and September; with strong N/NW winds, they may become 'trapped' in the shallow, largely enclosed North Sea, and heavy passages may be seen flying back north up the British east coast as they re-trace their steps back to the Atlantic over northern Scotland.
This bird is 40-50 cm in length with a 95-110 cm wingspan. It has the typically "shearing" flight of the genus, dipping from side to side on stiff wings with few wingbeats, the wingtips almost touching the water. Its flight is powerful and direct, with wings held stiff and straight, giving the impression of a very small albatross.
This shearwater is identifiable by its dark plumage. In poor viewing conditions it looks all black, but in good light it shows as dark chocolate-brown a silvery strip along the centre of the underwing.
The Sooty Shearwater feeds on fish and squid. They can dive up to 60 m deep for food, but more commonly take surface food, in particular often following whales to catch fish disturbed by them. They will also follow fishing boats to take fish scraps thrown overboard.
It breeds in huge colonies, nesting in burrows which are visited only at night to avoid predation by large gulls.
In New Zealand, Sooty Shearwater (or Tītī) are traditionally harvested each year by the native Maori. Young birds just about to fledge are collected from the burrows, plucked and often preserved in salt. As a consequence, the consumption of cooked Tītī can be somewhat of a salty experience.
External links
- Website of a long-term Sooty Shearwater research project (http://www.otago.ac.nz/titi) (New Zealand)nl:Grauwe pijlstormvogel