What is the difference between cormorants and shags?

Cormorants and shags are two very similar and closely related birds – and you’d easily be forgiven for mistaking their identity. Here’s our guide to telling cormorants and shags apart.

A cormorant with stands in the water with its wings aloft to dry them. A second cormorant has white patches, a mark of the breeding season.

Two cormorants

They’re both black, pre-historic-looking birds that dive for fish and hang their wings out to dry in a familiar regal pose. It can be hard to tell the difference, especially when you see an individual by itself.

A common shag

Is it a cormorant or a shag?

Cormorants are identifiable by their brown-black feathers. In the breeding season, they have white patches on their thighs and the underside of their chin. They’re heavy birds with a thicker beak and sit low in the water. Cormorant eyes are striking green, surrounded by bare skin. When flying, they resemble a pterodactyl and are generally solo travellers.

In contrast, shags are smaller birds with more slender bodies and a slimmer bill. Shag eyes are emerald and surrounded by feathers. They also have black plumage but with a green gloss and a purple tinge to the wings. Shag heads are smaller with a peaked forehead, resembling a snake. In the breeding season, they have a tufted crest on their foreheads.

A large black water bird with a hooked orange beak perches on a branch in the water with its wings stretched out to dry.

Find out more about cormorants

From where they live to how they breed and eat, discover more with our guide to cormorants

Where can you find cormorants and shags?

While half of the world’s shags live in the UK, cormorants are more widespread and found inland. Shags typically keep to coastal areas only.

Cormorants are also coastal birds, but some have colonised our inland waters, which provide excellent fishing grounds. If you’re on our canals or rivers and wondering if you’re looking at a cormorant or shag, it’s most likely a cormorant.