When its cliff ledges are thronged with birds, the air loud with calls and reeking of guano, a big guillemot colony can tickle many senses. Scotland has the bulk of Britain’s breeding guillemots.
What to look for
Ashore, guillemots stand upright on ledges or on flat-topped inshore stacks. Summer plumage is dark brown above and on the head, white on the belly. At sea, guillemots often fish in groups.
No other bird in the world breeds in such close proximity to its neighbours as the guillemot. Some literally press shoulder-to-shoulder as each warms its single egg. Chicks jump from ledges, before they can fly, to go to sea and feed with an adult (usually their father). Guillemonts, like razorbills, can dive very deep. One was videoed recently 89m (292ft) down at the base of a North Sea oil rig.
When and where to see
Guillemots come ashore in strength at colonies between April and late June. Chicks leave from mid June. Some adults may return to spend time ashore for parts of winter days. Colonies are widely scattered around many Scottish coasts, from the far south to the far north.
For more information see the RSPB's guillemot page.