Skellig Michael classified as a Special Protection Area in 1986, when they were recognised for containing both an usually large variety and population of birds. It is known as an eyrie for Peregrine Falcon. Other birds of interest include Fulmar, Manx shearwater ("Puffinus puffinus"), Storm petrel, Gannet, Kittiwake, Guillemot and Atlantic Puffin. A herd of goats lived on the island until recently, and it supports a population of rabbits and house mice, both relatively recent introductions, probably introduced in the 19th century by lighthouse attendants. Grey Seal haul out on the island's ledges. The word "Skellig" derives from the old Irish word
Wedge-tailed shearwater (in common with the other shearwaters) as an adaptation for swimming. This species is related to the pan-Pacific Buller's shearwater, which differs much in colour pattern, but also has a wedge tail and a thin black bill. They make up the "Thyellodroma" group, a superspecies of the large shearwaters that were for a long time included in the genus "Puffinus". Wedge-tailed shearwaters feed pelagically on fish, squid and crustaceans. Their diet is 66% fish, of which the most commonly taken is goatfish. It was thought that the species mostly took food from surface feeding, observations of feeding wedge-tails suggested that