Common Murre

The Common Murre is one of the most numerous seabirds of the Northern Hemisphere, nesting shoulder-to-shoulder in immense colonies on narrow cliff ledges. Its slim, dagger-like bill and upright stance distinguish it from the bulkier auks, while its close relative the Thick-billed Murre shares a similar overall pattern.

• Upperpart feathers are a warm chocolate-brown to blackish-brown, slightly paler and browner than the crisper black of Thick-billed Murre
• Underparts are clean white, with a sharp but somewhat irregular border between brown and white along the flanks
• Some individuals (the "bridled" morph) show a thin white eye-ring extending back as a fine line, visible on head feathers of certain birds
• Flight feathers are relatively narrow and pointed for an auk, supporting fast, direct flight on rapidly beating wings
• Tail feathers are short and squared, contributing to the bird's slim, elongated silhouette

• Breeding adults show a dark brown head, neck, and upperparts contrasting with white underparts
• Non-breeding adults show white extending up onto the face and throat, with a dark line behind the eye
• Juveniles resemble non-breeding adults but with softer, less crisp demarcation between dark and light areas
• The bridled morph, showing a white eye-ring and stripe, occurs mainly in higher-latitude populations and is not a separate subspecies but a plumage variant
• Sexes are alike; a complete molt after breeding includes a flightless period as flight feathers are shed simultaneously

Common Murres breed in dense colonies on narrow ledges of steep sea cliffs around the cold-water coasts of the North Atlantic and North Pacific. Outside the breeding season they disperse over open ocean and continental shelf waters, with northern populations moving to more temperate coastal waters in winter.

This species pursues fish underwater by diving from the surface and swimming with its wings, reaching considerable depths in pursuit of schooling prey. It lays a single, distinctively pointed egg directly on bare rock ledges without building a nest, an adaptation that helps prevent eggs from rolling off narrow cliffs. Its call is a low, growling "murre" sound given at dense breeding colonies.