Black guillemot

Black Guillemot

Black guillemot ©Tom Marshall

Black Guillemot

©Amy Lewis

Black guillemot

Enw gwyddonol: Cepphus grylle
Look out for the black guillemot all year-round at scattered coastal sites in Scotland, England, Wales and the Isle of Man. It tends not to travel far between seasons, breeding and wintering in the same spots.

Species information

Ystadegau

Length: 30-32cm
Wingspan: 52-58cm
Weight: 300-460g
Average lifespan: 11 years

Statws cadwraethol

Classified in the UK as Green following a 2024 update to the Birds of Conservation Concern 5: the Red List for Birds (2021).

Pryd i'w gweld

January to December

Ynghylch

The black guillemot is a small auk that breeds among rocks at the base of cliffs, on lower slopes, or on rocky islands; they tend to be seen in small numbers. Black guillemots eat fish and crustaceans. They dive down from the surface of the water, and swim to catch their prey. Black guillemots have been observed carrying prey in their beaks for over an hour before eating it or feeding their young. Many thousands of black guillemots breed in the UK, scattered along the coast in pairs or small groups. Not moving far between seasons, in winter, you are likely to spot them in their breeding places.

Sut i'w hadnabod

In summer, the black guillemot is black all over, with a large, white oval patch on each wing. In winter, it turns white, with black barring on its back, and black wings. It has bright red legs and a red gape.

Dosbarthiad

Nests on cliffs and rocky islands at scattered locations around the coast of Scotland, the Isle of Man and a handful of sites in England and Wales. Winters on, or near to, its breeding grounds.

Roeddech chi yn gwybod?

The black guillemot is also known as the 'tystie' in the Scottish Isles, which was probably derived from the Norse name for the bird.