Species Profile
Black Guillemot
Cepphus grylle
Black Guillemot
Quick Facts
Conservation
LCLeast ConcernAlso known as: Tystie
Think you've spotted a Black Guillemot?
Upload a photo and our AI will confirm it instantly
Confirm with a PhotoGallery
Appearance
The Black Guillemot showcases a striking seasonal plumage change. In summer, it sports a velvety black body with conspicuous white wing patches, complemented by vibrant red legs and feet. Their sharp, straight bills have a red inner lining.
Winter brings a dramatic transformation, with the bird adopting a mottled grey and white plumage. Juveniles resemble winter adults but with darker upperparts and less defined wing patches.
Identification & Characteristics
Colors
- Primary
- Black
- Secondary
- White
- Beak
- Black
- Legs
- Red
Attributes
Understanding Attributes
Rated 0–100 based on research and observation. A score of 50 is average across all bird species. These attributes are relative and don't necessarily indicate superiority.
Habitat & Distribution
Black Guillemots inhabit coastal areas across the northern Atlantic and Arctic regions. They prefer rocky shores, cliffs, and offshore islands, rarely venturing far from land. Their range includes the coasts of North America, Greenland, Iceland, and northern Europe.
In the UK, they are year-round residents along Scottish coasts and islands, with some populations in Northern Ireland and northern England. North American birds can be found from Alaska to New England, with some southward movement in winter.
Distribution
Where to See This Bird
Explore regional guides for locations where this bird has been recorded.
Diet
Black Guillemots are primarily piscivorous, feeding on small fish such as sand eels, capelin, and sculpins. They eat a variety of other sea creatures, such as squid, crustaceans, worms, and molluscs.
Unlike many seabirds, they forage in relatively shallow waters, typically diving to depths of 30-40 meters in search of prey whilst staying submerged for as long as two minutes while searching the seabed. Their short wings help them 'fly' through the water.
Behaviour
Black Guillemots are excellent swimmers and divers, using their wings to 'fly' underwater in pursuit of prey. They often bob on the water's surface, diving frequently.
On land, they exhibit a distinctive waddling gait and are more solitary than many other auk species, often seen in pairs or small groups rather than large colonies.
Calls & Sounds
The Black Guillemot's vocal repertoire includes a high-pitched, thin whistle, often described as a 'weeep' or 'teee-a'. During the breeding season, they produce a series of these whistles in rapid succession, creating a distinctive trilling sound that echoes along rocky coastlines.
They also utter a drawn-out whistle when disturbed by humans or other potential predators.
Nesting & Breeding
Black Guillemots form monogamous pairs, often returning to the same nesting site year after year. Breeding season typically begins in late spring, with courtship displays including synchronised swimming and billing.
Nests are located in crevices among rocks or cliffs, sometimes in man-made structures. The female lays 1-3 eggs, usually two, which are pale with dark speckles.
Both parents incubate the eggs for about 28-32 days. The chicks fledge after 30-40 days but continue to be fed by their parents for several weeks after leaving the nest.
Conservation
While currently listed as Least Concern, Black Guillemots face threats from oil spills, marine pollution, and climate change. Rising sea temperatures may affect their prey availability, potentially impacting breeding success.
Conservation efforts focus on protecting breeding habitats and reducing marine pollution.
Elevation
Sea level to 100 meters
Additional Details
- Predators:
- Main predators include large gulls, skuas, ravens, and occasionally marine mammals such as seals. On land, foxes and rats may prey on eggs and chicks.
Birdwatching Tips
- Look for their distinctive white wing patches when in flight
- Search rocky coastlines and offshore islands, especially in northern regions
- Listen for their high-pitched, whistling call near nesting sites
- Observe their diving behavior from coastal vantage points
Did You Know?
- Black Guillemots can dive to depths of up to 50 meters in search of food.
- They are one of the few seabirds that can drink saltwater, thanks to special salt glands.
- Unlike many auks, Black Guillemots can take off from calm water without running along the surface.
Community Photos
Be the first to share a photo of the Black Guillemot
Upload a PhotoIdentify Any Bird Instantly
- Upload a photo from your phone or camera
- Get an instant AI identification
- Ask follow-up questions about the bird
Monthly Birds in Your Area
- Personalised for your location
- Seasonal tips and garden advice
- Updated every month with new species