Stercorariidae - Skuas
The skuas are piratical birds; the American term for them (jaeger) comes from the Old German word to hunt. The skuas are essentially large, robust gulls, with long wings and a hooked beak. They feed mostly by kleptoparasitism, that is by stealing prey from other birds, and they are not averse to eating other birds, particularly auks and petrels, and Great Skuas (or Bonxies) will even attack herons and geese, which much larger than themselves. Skuas are long-lived and generally monogamous (as are most seabirds), though pairs will 'divorce' if they don't raise any chicks in a year.
Britain is home to most of the world's breeding population of Great Skua, which is found in the north and west of Scotland.