Sooty Shearwaters

Sooty Shearwaters (Puffinus griseus, also known as Titi or the muttonbird) are medium-sized burrow nesting seabirds that breed on New Zealand's off-shore islands with a small number still attempting to nest on the mainland.

Breeding colonies of Sooty Shearwaters are found around the coasts of Southern South America and South-east Australia. They are the commonest seabird in the New Zealand region.

Breeding range of Sooty Shearwaters within New Zealand extends from the Three Kings Islands (34 S,172 E) to Maquarrie Island (54 S, 159 E).

Breeding abundance in New Zealand centers around islands in Foveaux Strait and islands adjacent to Rakiura (Stewart Island, New Zealand's third largest island). Large populations are also found on The Snares, with smaller populations on other New Zealand Sub Antarctic Islands, Chatham Islands, Antipodes, Auckland Island, Campbell Island and Macquarie Island .

Sooty Shearwaters are vulnerable to mammalian predation and as they lay one egg per year have a low annual productivity. Colonies on the offshore islands have remained large but colonies on the mainland have either contracted or disappeared.

Sooty Shearwaters return to the colony after 3-4 years, however the majority of Sooty Shearwaters do not breed until 5-7 years of age. The maximum longevity recorded is 34 years, supported by the recapture of 2 banded adults from The Snares in the 1999-2000 breeding season.

Both breeding and non breeding birds return to the colony in late September or early October for courtship and preparation of burrows which may extend from 0.4 m to 4 meters in length. On average an adult Sooty Shearwater weighs 819=76 grams.

When on land, Sooty Shearwaters are almost entirely nocturnal, landing at dusk in the cover of darkness and returning to the sea at dawn. Each breeding pair lays a single egg, which is not replaced if lost or damaged. Incubation is for approximately 53 days, the chick hatching and spending the next 86-106 days in the burrow before emerging, stretching wings and fledging from mid April to late May, migrating to the Northern hemisphere. Further information is available at http://nzbirds.com/Titi.html


The need for this research
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Matauranga and science
About titi
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