Razorbill, Alca torda.

Razorbill, Alca torda

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 largest living members of the auk family, measuring about 45 cm in length, the size of a small duck. They are also the closest living relatives of the extinct great auk. Razorbills can be distinguished from other alcids by their thick head and neck, heavy, razorlike 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.

Razorbills breed in the Maritime provinces, the European north Atlantic, Greenland, and a few isolated colonies on the tips of the Ungava peninsula and Baffin Island. Although there are only a few razorbill breeding sites located in the Canadian Arctic, each colony contains several thousand birds, which constitute an important part of the bird life of the surrounding area. 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. Eggs are 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 parent, 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. Canadian razorbills migrate to the Atlantic coast to winter, occasionally ranging south as far as South Carolina. There were significant declines in the populations of razorbills in the mid-20th century, due mostly to hunting, egg-collecting and pesticide exposure.