The Arctic Skua and its breeding grounds

The Arctic Skua is a circumpolar Arctic species that breeds as far north as Spitzbergen. At the southern end of its range, it breeds in small colonies in parts of the Hebrides and the north of Scotland. But in the British Isles it is common only in Shetland (59°N) where it is fairly widespread. Large colonies are found on the islands of Fair Isle, Foula, Bressay, Noss, Fetlar and Unst. Isolated pairs and loose colonies can be found throughout Shetland. Recently it has been giving ground to the Great Skua or Bonxie. In 1950, the largest Shetland colony of Arctic Skuas was to be found in the bird reserve of Hermaness on Unst, the most northerly point of the British Isles. This colony was completely over-whelmed by Bonxies as they rapidly increased in numbers between 1950 and 1975, completely taking over the bird reserve. The largest compact colonies of Arctic Skuas are now to be found on Fair Isle and Foula: about 130 pairs breed on Fair Isle and 300 pairs on Foula. Both colonies are under attack. The Foula colony is being pushed into a smaller and smaller area by the spread of the Bonxies. On Fair Isle, the predators are human. Unfortunately, Arctic Skuas are recorded as having been shot on Fair Isle–bodies with bullet holes having been found. In spite of such depredations about 120–140 pairs have bred since 1975.