Razorbill  (Alca torda)

This handsome bird has a characteristic deep, flattened (1), wedge-shaped (3) bill, which is black in colour with a white line. The underparts are white, and the black upperparts are darker than those of the similar guillemot (Uria aalge). Juveniles in their first winter have smaller and more pointed bills, which lack the white line seen in adults (1). This species is not particularly vocal, but a deep creaking 'urrr' is produced by breeding individuals (1). In Cornwall, an alternative common name for the razorbill is 'murre', which is probably imitative of this call (3). The scientific name Alca is thought to derive from the Icelandic word for this bird, Alka, which is thought to imitate another call of the razorbill, a harsh 'arrc-arrc' (3).

Occurs in the North Atlantic; Britain is a stronghold (4). This species breeds in internationally important numbers around the British coast. In combination, British and Irish totals represent around 20% of the world population (1).

Inhabits both coastal and oceanic waters (2), and breeds on coastal cliffs and rock stacks in summer (2).

Breeding colonies form in spring; each pair has a single brood consisting of one egg each year (1). The egg is laid in a crevice or hole, or a nest of pebbles (1). The young leave the breeding colony while still unfledged, at around 18 days after hatching and are looked after by the parents for some time (7).

In winter, the diet is known to consist mainly of fish such as herring, whiting and sand eel, although crustaceans and worms are also eaten (4). Patterns of movement are complex, but it seems that birds in their first year travel further distances than adults (4).

This species can be very seriously affected by oil pollution, and is particularly vulnerable when dispersing away from the breeding colonies (1). Other types of marine pollution, including heavy metals used in industry and organochloride pesticides used in agriculture are also threats and are known to cause deaths (1). Furthermore, food shortages, which may be caused by over-fishing, are a potentially serious problem (1).

Seabirds, including the razorbill, were among the first bird species given protection by legislation. A number of major seabird colonies are protected by the RSPB and other conservation organisations as nature reserves (8). Research into the ecology of seabirds, and the effects of the industrial fishing of sand eels on their populations is needed (1).

For more on British birds see the RSPB website:
http://www.rspb.org.uk

Information authenticated by the RSPB:
http://www.rspb.org.uk/