Great Cormorant

The Great Cormorant is a large, powerful waterbird with an exceptionally broad global distribution, found across Europe, Asia, Africa, Australia, and a small part of northeastern North America. It is the largest cormorant across most of its range.

Appearance

Adults are glossy black overall with a bronzy or greenish sheen, a distinctive white patch on the throat and chin, and yellow-orange facial skin at the base of the heavy bill. In breeding plumage, adults also develop a white patch on the thigh and fine white plumes on the head and neck.

Key field marks

• Large, bulky build, the biggest cormorant across most of its range
• White throat and chin patch bordered by yellow-orange facial skin
• White thigh patch in breeding plumage
• Heavy, hook-tipped bill

Similar species

Double-crested Cormorant, found in North America, is smaller with orange facial skin extending in a point behind the eye rather than a clean white throat patch. Where ranges overlap (such as parts of eastern North America), Great Cormorant's larger size and white throat patch are useful distinctions.

Habitat and range

Great Cormorants occupy an enormous range across coastal and inland waters of Europe, Asia, Africa, Australia, and a limited breeding range in northeastern North America, using habitats from rocky sea coasts to inland lakes and rivers.

Migration

Northern populations are migratory, moving to milder coastal wintering areas, while populations in warmer parts of the range may be resident. The species has expanded its inland breeding range in parts of Europe and North America in recent decades, sometimes generating conflict with fisheries.

Behavior

Great Cormorants forage by diving from the surface and pursuing fish underwater with powerful propulsion from their feet, often foraging alone or in loose groups, and like other cormorants must periodically dry their wings after diving.

Voice

Adults are largely silent away from colonies, though deep guttural grunts and croaks are given during breeding displays and nest defense.

Nesting and breeding

They nest colonially on cliffs, rocky islands, or in trees, building a bulky stick nest. Clutches typically number three to four eggs, and both parents share incubation and chick-rearing duties over the breeding season.