Wildlife on St Kilda

St Kilda is a haven for wildlife with 210 different species of bird – some one million seabirds – having been recorded. Here you’ll find an estimated 300,000 pairs of puffins (that’s 50% of the entire UK population), 60,000 pairs of gannets, 40,000 pairs of fulmars, 20,000 pairs of guillemots, 10,000 pairs of kittiwakes, plus Manx shearwaters, storm petrels, Leach’s petrels and great skuas. Great skuas are also known as Bonxies, from their tendency to swoop down and “bonk” visitors on the head. Waving your arms around is said to be an effective deterrent. They are large and aggressive birds, sometimes called “pirates of the sky”, and will attack and eat smaller birds such as kittiwakes and puffins.


Another island – well, rock really – in the group is Boreray, home to the largest gannet colony in Europe, about 50,000 pairs. That’s 37% of the total UK populous and 25% of the world’s. Watch out for these stunning birds as they dart at great speed into the sea for fish.

St Kilda has its own species of four-horned Soay sheep, St Kilda wren and St Kilda mouse. The mice are descended from wood mouse because the house mouse became extinct after the houses were abandoned. Dolphins, minke whales and sometimes killer whales accompany vessels as they make their way out to these remote islands. The feral Soay sheep (the most primitive domestic breed in Europe) have been investigated by scientists since 1959. The continuation of this survey has produced one of most detailed population studies in the world.

The geology of the archipelago may also be of interest to you. Some of the rock is highly magnetic. The coastline contains many caves and the sharp, jagged skylines exist because the Ice Age bypassed the St Kilda islands and thus the rocks are unworn. Scientists believe that many years ago St Kilda was just one large volcano. The volcano exploded and rising tides have caused the appearance of many smaller islands and sea stacks.