The smooth square fissured rocks of Gorregan ( high) is a contrast to the other islands which are a ″disordered jumble″ of rocks. The only plants recorded are common scurvygrass (Cochlearia officinalis), rock sea–spurry (Spergularia rupicola) and orache (Atriplex sp). The breeding colony of European storm petrel had 49 occupied sites recorded during the Seabird 2000 survey and there is a large colony of kittiwake, although in 1984 there was no breeding because of (possible) predation by carrion crow (Corvus corone) or common raven (Corvus corax). Other breeding birds are razorbill and guillemot. Grey seals use the island as a pupping site.
