Alca torda | Razorbill | Crosán



Conservation status

This species is Red-listed according to Birds of Conservation Concern in Ireland 2020-2026 and is of high conservation value as a result.

The razorbill is classified as ‘Near Threatened’ on both a global and European scale according to the last IUCN Red List assessment in 2018. The population trend was also noted as decreasing. 

Species Biology


This member of the Auck family has a black back and head with a thick black beak and white underparts.

The Razorbill can be distinguished from the similar looking Guillemot by its much thicker beak compared to the thinner bill of the Guillemot. Additionally, the Razorbill is a smaller bird with black upperparts compared to the lighter brown of the Guillemot.

The Razorbill stands at approximately 37-39 cm with a wingspan of 63-97 cm.  Weight can range from 590-730 grams. 


Being a marine bird species, the Razorbill feeds on marine life such as fish like sandeels and sprats as well as various invertebrate species. 


This species is associated with marine habitats and will be found on suitable coasts and islands.

Suitable nesting habitat for this species includes sea cliffs but it will also nest in screes and cracks in cliffs that offer a secluded nesting site. 


During the breeding season, a single egg of approximately 90 grams is laid followed by an incubation period of 32-39 days. The young will fledge after 14-24 days.

Average life expectancy for a Razorbill is approximately thirteen years with individuals reaching breeding age at about four years. 

Threats faced

Pollution of the marine environment and declining fish stocks are a significant driver in the decline of the Razorbill.


World distribution(GBIF)

Irish distribution

In a similar vein to the Puffin, the Razorbill winters at sea and will only come to land during the breeding season.

During the breeding season, there are long established, large breeding colonies of Razorbill at the Cliffs of Moher in county Clare, the Saltee Islands off County Wexford and Horn Head in County Donegal and small colonies at other locations.

Temporal change

Records submitted to Data Centre in 2022

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