Basic Information

Scientific Name Phalacrocorax carbo
Featured bird groups Shore birds
Phylum Chordata

Great Cormorant is a beautiful bird, widespread throughout the world. Its fishing ability may be as turned to man’s advantage in the Far East, or considered as fish competitor in several other countries and persecuted.Adult in breeding plumage has glossy black plumage overall, with bronze reflections on lower back, rump and wings, and rather blue in upper back and tail. Plumage shows scaled effect.  Underparts are black. We can see a conspicuous white patch on the thighs. On the head, the chin is black, but cheeks and throat are covered with bare white skin. Head is black with more or less white feathers on the loosely crested nape which is formed by elongated feathers. According to each bird, we can see white short feathers extending broadly on the rear neck and ending in narrower collar on the foreneck. The thin, straight bill is horn-coloured, with yellow to orange-red gape and hooked tip. The eyes are emerald. The short legs and the webbed feet are black.

Habitat

Great Cormorant frequents open marine and inland waters. It is found on rocky or sandy sheltered coasts and estuaries. It is rarely seen far from the coast. The species P.c. sinensis prefers inland waters and frequents lakes, reservoirs and rivers. Great Cormorant breeds on cliffs, among boulders, man-made structures and inshore islands. The birds which nest inland breed on trees, bushes, in reedbeds and even on the bare ground.

Behaviour

Great Cormorant feeds primarily on fish, but it also takes crustaceans and amphibians. It usually feeds in shallow water. When the prey is caught with the bill, the bird brings it to the surface, in order to shake it and then, it tosses it before swallowing in the right way.  It swims under water in order to pursue its prey, only using its webbed feet. Outside breeding season, birds may fish in small groups, but they are often seen alone. Great Cormorants spend most of their time sitting upright in rows on a sandy bank, or trees and man-made structures. Great Cormorants have special feathers witch allow air to escape and water to penetrate the plumage. Under water, swimming is more efficient. But it means that the bird has to dry its plumage in a characteristic posture, with wings spread out, perched on a branch. This pose may also help to digestion. It consumes about 400 to 700 grams of fish per day.

Voice

Great Cormorant utters guttural croaking at nest and roost. It is rather silent when away from the colony.

Related Aves