Thick-billed Murre

Identification

The thick-billed murre is the largest living member of the auk family, measuring 40–48 cm in length with a wingspan of 64–81 cm. Adults are black on the head, neck, back and wings with contrasting white underparts. The most distinctive feature is the thick, short bill with a characteristic white gape stripe. In winter, the lower face becomes white. These birds look noticeably shorter and stockier in flight compared to their close relative, the common murre.

Key field marks for distinguishing thick-billed from common murres include the thicker, shorter bill, darker head and back, and the presence of either a white eye-stripe or white bill-stripe (but never both). First-year birds have smaller bills and less obvious markings, making head pattern the most reliable identification feature at that age.

Range & Habitat

This species is distributed across the polar and sub-polar regions of the Northern Hemisphere, with four recognized subspecies occupying different sectors. The Atlantic race inhabits coasts from northeast Canada through Greenland, Iceland, Scandinavia, and Svalbard; the Pacific race ranges from Alaska through the Aleutian Islands to Kamchatka and the Kuril Islands; while two additional subspecies occupy the Russian Arctic from the Taymyr Peninsula to the New Siberian Islands and Wrangel Island.

Thick-billed murres are pelagic birds spending their entire lives at sea in waters below 5°C, except during breeding season. They move south only in winter to maintain access to ice-free waters, ranging as far as the northernmost Atlantic and Pacific regions. They are rare vagrants to southern European countries and occasionally appear off the coasts of Britain, Ireland, and the Netherlands.

Behaviour & Diet

These auks form some of the most spectacular breeding colonies in the Northern Hemisphere, sometimes exceeding a million birds crowded onto narrow cliff ledges and steep rocky faces. Remarkably, they maintain the smallest territory of any bird species, requiring less than one square foot per individual. Despite these cramped conditions, thick-billed murres remain one of the most abundant marine birds in the Northern Hemisphere.

Breeding pairs lay a single egg annually on bare rock without constructing a nest. Both parents share incubation duties and chick-rearing responsibilities. Due to the enormous energy demands of flight, adults can only deliver one food item to their chick at a time. Chicks remain in the colony for 18 to 25 days before fledging. These birds produce harsh cackling calls at breeding colonies but remain silent at sea.

Best Time & Places to See It

The breeding season is the best time to encounter thick-billed murres, when they congregate in vast, accessible colonies on coastal cliffs. Locations with major breeding populations include Greenland, Iceland, Svalbard, and various Arctic coastal regions. For Pacific populations, the Aleutian Islands and Alaskan coasts offer excellent viewing opportunities during the breeding season when birds are concentrated and vocal.

Winter observations are challenging as birds disperse into open sea far from shore, though they remain in northernmost ice-free waters. Historically, winter movements brought flocks to the Great Lakes and St. Lawrence River region of North America, though such irruptions have not occurred since 1952.

Photography Tips

Breeding colonies offer unparalleled photographic opportunities with massive concentrations of birds in dramatic cliff-side settings. Use fast shutter speeds to capture the dynamic activity—take-offs, landings, and communal displays. The contrast between black upperparts and white underparts provides striking compositional opportunities, particularly when photographing birds against sea or rocky backgrounds.

Position yourself to backlight the white underparts while maintaining detail in the black plumage. Capture the distinctive white gape stripe and bill profile as diagnostic field marks. Early breeding season provides the best light and most active behavior, with birds performing communal displays to synchronize breeding cycles. Wide-angle lenses help convey the scale and density of these extraordinary colonies.