The great cormorant, also known as just cormorant in Britain, as black shag or kawau in New Zealand, formerly also known as the great black cormorant across the Northern Hemisphere, the black cormorant in Australia, and the large cormorant in India, is a widespread member of the cormorant family of seabirds. It breeds in much of the Old World, Australasia, and the Atlantic coast of North America.
Region
Eurasia, Africa, Australasia and North Atlantic coasts
Typical Environment
The great cormorant occupies coastal seas, estuaries, large rivers, reservoirs, and lakes across much of the Old World and the North Atlantic coast of North America. It breeds colonially on sea cliffs, rocky islets, coastal trees, and sometimes inland trees or ground sites near water. Nonbreeding birds range widely along coasts and inland waters, often following fish concentrations. It adapts well to human-altered wetlands, including fish ponds and harbors.
Altitude Range
Sea level to 2000 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
The great cormorant is a powerful pursuit diver that chases fish underwater using its feet and partially spread wings. After fishing it often perches with wings outstretched to dry, as its plumage is only partially waterproof. In parts of East Asia, cormorants (including this species) have historically been trained by fisherfolk to help catch fish.
Group of great cormorants in Latvia
Cormorant fishing in Wuzhen Xizha, Zhejiang, China
Temperament
social and active
Flight Pattern
strong, direct flight with steady, rapid wingbeats; often flies low over water
Social Behavior
Breeds in dense colonies, often mixed with other waterbirds, building stick nests in trees, on cliffs, or on the ground. Pairs form for the season and engage in conspicuous courtship displays at the nest. Outside the breeding season, birds roost communally and can form large feeding and loafing flocks.
Migratory Pattern
Partial migrant
Song Description
Generally quiet away from colonies, but at nesting sites it gives harsh, guttural croaks and grunts. Calls are coarse and throaty, used in displays and territorial interactions.
Plumage
Mostly glossy black with a greenish sheen; breeding adults show white thigh patches and filamentous white head plumes. Nonbreeding birds are duller with more brownish tones and paler underparts. Juveniles are brown with whitish throat and belly.
Diet
Primarily fish of small to medium size, including schooling and benthic species. It also takes crustaceans and occasionally amphibians when available. Birds dive from the surface and pursue prey underwater, grasping fish with the hooked bill and swallowing them head-first.
Preferred Environment
Feeds in coastal waters, estuaries, sheltered bays, large rivers, reservoirs, and lakes. Often forages near piers, breakwaters, and fish farms where prey is concentrated.
