Uria aalge


The guillemot is a medium-sized auk which breeds in tightly packed colonies on perilous ledges, cliff tops and rocky outcrops around the coast. In May and June, females will lay a single egg; once the chick is three weeks old, it will dramatically plunge into the sea with its father, who will care for it at sea until it is independent. Guillemots eat fish, crustaceans and molluscs, diving from the surface of the water and swimming in hot pursuit of their prey.

How to identify

Guillemots are chocolate-brown above and white below. A 'bridled' form occurs in which the eye is ringed with white, which extends as a line towards the neck. Guillemots can be distinguished from razorbills by their colour and by their longer, narrower, darker bill. Guillemots nest in tight groups on narrow ledges on cliffs, while razorbills tend to nest singly or in small groups in ravines and other rocky sites, often lower down a cliff. In the winter, they have white faces.

Where to find it

Nests on coastal cliffs. Can be seen around most of our coasts during migration.


When to find it

  • April
  • May
  • June
  • July
  • August

How can people help

The survival of seabirds like the guillemot is threatened by the pollution, overexploitation and degradation of our marine and coastal habitats. The Wildlife Trusts are working with fishermen, researchers, politicians and local people towards a vision of 'Living Seas' where marine wildlife thrives. This work has recently had a massive boost with the passing of the Marine Bill, promising sustainable development of the UK's marine environment. Do your bit for our Living Seas by supporting your local Wildlife Trust.

Species information

Common name
Latin name
Uria aalge
Gulls and seabirds
Length: 38-45cm Wingspan: 67cm Weight: 690g Average Lifespan: 23 years
Conservation status
Classified in the UK as an Amber List species under the Birds of Conservation Concern review.