Razorbill

The Razorbill, or Alca torda, is a colonial seabird of the North Atlantic and the sole extant member of the genus Alca within the family Alcidae. This bird is characterized by its striking black and white plumage, with a predominantly black upper body and a white underside. During the breeding season, a distinctive white line extends from the eyes to the end of the bill. The Razorbill is a robust bird, with a deep, laterally compressed bill adorned with vertical grooves.

Identification Tips

Adult Razorbills can be identified by their black head, neck, back, and feet contrasted with a white belly. The bill is black, thick, and blunt-ended with white lines on the vertical grooves. In non-breeding season, the throat and face behind the eye become white, and the bill's white line is less prominent. The tail is slightly longer in the center compared to other auks, giving it a unique profile.

Habitat

Razorbills are found in sub-arctic and boreal waters of the Atlantic, preferring islands, rocky shores, and cliffs for breeding. They thrive in water surface temperatures below 15°C and can often be seen in larger estuaries with lower salinity levels.

Distribution

This species breeds on northern Atlantic coasts, from the Baltic and White Seas to eastern North America and from northwestern Russia to northern France. Razorbills winter at sea, with North American birds ranging south to New England and Eurasian birds moving as far as the western Mediterranean.

Behaviour

Razorbills are agile birds, capable of both flight and diving. They are monogamous, pairing for life, and exhibit female-enforced monogamy. Both sexes share incubation duties and forage for their young. They are migratory, spending winters in the Atlantic Ocean.

Song & Calls

The Razorbill's calls are typically heard during the breeding season, with pairs engaging in a duet of guttural notes that strengthen their bond.

Breeding

Razorbills reach breeding maturity at 3-5 years of age and may skip breeding in some years. They nest in crevices among cliffs and boulders, often reusing the same site annually. A single egg is laid per year, with both parents sharing incubation responsibilities.

Similar Species

The Razorbill can be confused with the Common Murre or Guillemot but can be distinguished by its thicker bill with distinctive white lines and longer tail.

Diet and Feeding

The diet consists mainly of mid-water schooling fish such as capelin and sand lance, as well as crustaceans and polychaetes. Razorbills dive using their wings to propel themselves towards prey, often diving to depths of 25 meters but capable of reaching up to 120 meters.

Conservation status

The Razorbill is currently listed as Least Concern by the IUCN. However, it faces threats from habitat destruction, oil spills, and food quality deterioration. Conservation efforts include protection under the Migratory Bird Treaty Act and management of breeding sites to mitigate human impact.