The European Shag (Gulosus aristotelis) is the west coast's smaller cormorant, with glossy green plumage and, in breeding dress, a distinct forward-curving crest on the crown. It measures 68-78 cm in length, has a wingspan of about 95-110 cm and weighs 1,700-2,250 grams, noticeably slimmer and smaller than the Great Cormorant, with a thinner neck and a more slender bill. The plumage is black with a strong green metallic sheen, the legs and feet dark and the base of the bill yellowish; unlike the Great Cormorant in breeding plumage, it lacks white cheek and thigh patches. Juveniles are dark brown without a crest and show a more uniformly dark underside.
The Shag is generally silent, though hoarse, croaking and grunting sounds can be heard at the breeding colonies. Tied to salty, open sea, it occurs in Sweden only along the west coast, chiefly in the outer Bohuslän archipelago; long a rare visitor, it has established itself as a regular breeder there in recent decades, with a national population in the low thousands of pairs and still increasing, even as the species declines globally, where it remains classed as of Least Concern. It is almost never found in the Baltic Sea, since it requires high salinity and open marine conditions, and is largely sedentary. It breeds in colonies on rocky, wave-exposed skerries and islands, building a nest of seaweed, twigs and plant material on a rock ledge, in a crevice or among boulders; the female lays 2-4 eggs, and both parents share roughly a month of incubation before the chicks are fed in the nest for several weeks. Its diet is almost exclusively fish, especially bottom-dwelling species such as sandeel, caught by diving from the surface to considerable depths, often in the range of 20-60 metres.
Read about this species in Swedish →