Acadia National Park

Description  ADULT SUMMER Has blackish head, neck, and upperparts, with clean demarcation on chest from white underparts. ADULT WINTER Similar, but throat becomes white (lacks white cheeks seen in winter Common). White gape stripe is less striking. JUVENILE Similar to winter adult.

Dimensions  Length: 18" (46 cm)

Habitat  Restricted mainly to cold northern and Arctic seas; smaller numbers breed in Newfoundland and Nova Scotia. Nests colonially on sea-cliff ledges, often found alongside Common Murre. Pelagic outside breeding season, most remaining in Arctic waters.

Observation Tips  Abundant in Arctic, but smaller and more accessible colonies may be observed in Newfoundland and Nova Scotia.

Range  Eastern Canada, Western Canada, Alaska, California, New England, Mid-Atlantic

Voice  Utters rumbling har-rrrhr calls at breeding colonies. Otherwise silent.

Discussion  Marginally smaller than similar Common Murre. Has shorter, thicker bill (almost gull-like) with striking white stripe along gape. Neck is thicker than Common, and plumage darker overall, although latter feature is often hard to discern in poor light. Adopts upright posture when resting on cliff. Swims well, dives frequently, and flies on whirring wingbeats. Sexes are similar.