Almost a sixth of the world’s population and 36% of Scotland’s population breeds on St Kilda, though numbers are growing at other colonies, such as the Bass Rock.
The only other colony on NTS property is at Fair Isle.
Food: Mainly fish, caught by diving from heights of 10-40 m and staying under from 5 – 20 s.
Nest Site: On ledges of cliffs, sea stacks where nests are evenly spaced but never touching (60-80 cm apart). : Large compact pile of seaweed, grass, feathers and earth all cemented on a substrate of excreta.
Breeding: Mid April to mid May where one egg is laid.
Wintering: Go south to sub-tropical waters sometimes into tropical waters off the coast of west Africa.
Distribution: UK, Ireland, Faeroes, Iceland and Norway.