Razorbill (Alca torda)

 

There were significant declines in the populations of razorbills in the mid-20th century, due mainly to hunting, egg-collecting and pesticide exposure. Ironically, these birds are also the closest living relatives of the great auk, which was hunted to extinction in the early 1800s.

Description

The razorbill has the elegant black and white breeding plumage that is characteristic of the alcid family. Its head, neck, back and feet are black, and its belly is white. In the winter, its plumage is similar but duller, and the lower half of its face and its neck are white. Males and females are similar in appearance and are the size of a small duck, making this the largest living member of the auk family. Razorbills can be distinguished from other alcids by their thick head and neck, heavy, razor-like bill and upturned tail. The bill has two fine white lines running vertically across its tip, adding to its ‘razorblade’ appearance. The razorbill’s calls include a whirring whistle and a deep, ‘hey-all!’ growl.

Distribution

Razorbills breed on the coasts of the Maritime provinces, the European north Atlantic, Greenland, and on isolated areas of the Ungava peninsula and Baffin Island. Canadian razorbills migrate to the Atlantic coast to winter, occasionally ranging south as far as South Carolina.

Ecology

These birds nest on ocean cliffs, in rocky crevices or among boulder piles, where each pair lays one egg either directly on the rock, or in a rudimentary nest made of a few pebbles and scraps of vegetation. The egg is incubated by both parents for about five weeks. Once the chick is about 18 days old, it takes to the sea with its parents, where it spends another two months tended by the male, while it gains weight and grows its adult plumage. Razorbills do not breed until they are four or five years old, after which time they form long-term pair bonds.

Like most alcids, razorbills are seabirds specializing in diving from the surface of the ocean to pursue small fish, particularly sand lance and capelin, although they also consume some invertebrates. Their webbed feet and small wings are ideal for diving and swimming rapidly underwater- they have been taken in nets as deep as 120 metres- but are relatively inefficient in the air and on land. It is therefore not surprising that, after the breeding season, razorbills return to the ocean, where they remain until the next spring.