Manx shearwater

How it lives

Manx shearwaters nest in burrows on islands and visit them only at night, when colonies fill with croons, howls and screams. Breeding starts in March. During the breeding season birds commute to feeding grounds up to 1,500 km away. They live very long lives: the British and Irish ringing record is 50 years, 11 months and 21 days.

Where it goes

A full migrant. Colonies are largely empty from July to March. Birds from Skomer Island, Wales, travelled south along the west coast of Africa, crossed to Brazil, and spent the winter on the Patagonian Shelf off Argentina, near 40 degrees south. All 12 tracked birds wintered in that same small area. Southbound trips took 14 to 44 days. Smaller numbers winter off south-west South Africa.

We only draw a journey on the map when scientists have tracked it or clearly documented it. For this animal we have not found one yet.

Populations

IUCN (2018): Least Concern, with an unknown overall trend. It is decreasing in North America and unknown in Europe. Europe holds more than 95% of the breeding range, with 342,000 to 393,000 breeding pairs (684,000 to 785,000 mature individuals) in the assessment cited by IUCN (2015). About three-quarters of British and Irish birds breed on Skomer, Skokholm and Rum. The UK had about 300 thousand pairs in 1998 to 2002, and BTO notes that recent surveys suggest a rise of up to 50% since the 2000 census. It is Amber listed in the UK. Threats named by IUCN include rats and feral cats on breeding islands, chick harvesting in the Faroes (1,000 to 5,000 chicks a year) and artificial light.