What is the difference between cormorants and shags?

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.

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.

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.