St Levan common species such as northern gannet ("Morus bassanus"), Manx shearwater ("Puffinus puffinus"), common guillemot, ("Uria aalge") and razorbill ("Alca torda"), as well as rarer birds such as Balearic shearwater ("Puffinus mauretanicus") and Cory's shearwater ("Calonectris borealis"). The headland of Tol-pedn (or Gwennap Head) is favoured by birdwatchers and many travel the length and breadth of Britain to track rare seabirds. Some of the butterflies that can be found on the coast include grayling ("Hipparchia semele"), silver-studded blue ("Plebejus argus"), small pearl-bordered fritillary ("Boloria selene") and wall ("Lasiommata megera"). There is also a day-flying moth, the thrift clearwing ("Synansphecia muscaeformis"); the
Galápagos shearwater Galápagos shearwater The Galápagos shearwater ("Puffinus subalaris") is a small shearwater. Until recently it was considered to be a subspecies of Audubon's shearwater, but it is actually one of two members of a very ancient lineage of the small "Puffinus" species, the other being, as indicated by mtDNA cytochrome "b" sequence data, the Christmas shearwater. It is an endemic breeder of the Galápagos Islands, and is largely sedentary, although individuals are commonly seen as far as the Oaxacan coast of Mexico. The Galápagos shearwater has dark brown upperparts, undertail and underwing flight feathers, the rest of the underparts plumage being