Manx Shearwater Puffinus puffinus


Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The overall population trend is unknown however it is not believed to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
In Europe (which covers >95% of the breeding range), the breeding population is estimated to be 342,000-393,000 breeding pairs, equating to 684,000-785,000 mature individuals or 1,026,000-1,177,500 individuals (BirdLife International 2015). Brooke (2004) also estimated the global population to be at least 1,000,000 individuals.

Trend justification
The overall population trend is unknown. The population trend is decreasing in North America (based on BBS/CBC data: Butcher and Niven 2007). The European population trend is unknown (BirdLife International 2015).

Distribution and population

This species breeds in the north Atlantic, with major colonies on the Atlantic coasts of the United Kingdom and Ireland. Colonies are also present on Iceland, islets off Massachusetts (U.S.A.) and Newfoundland (Canada), as well as on the Azores, Portugal and the Canary Islands, Spain. It undergoes transequatorial migration, expanding the range in winter to include the Atlantic coast of South America below the equator and the south-west coast of South Africa.


This marine species is mainly found on waters over the continental shelf, feeding mainly on small shoaling fish but also on some squid, crustaceans and offal. Prey is caught mainly by pursuit-plunging and pursuit-diving, either alone or in small flocks. Breeding starts in March, forming colonies on coastal or offshore islands, nesting in burrows (del Hoyo et al. 1992).


Invasive species represent one of the greatest threats to this species. Domestic Pigs Sus domesticus were the likely driver of the extinction of Manx Shearwater on Bermuda (Bourne 1957). Chick predation by Rats Rattus spp. and Feral Cats Felis catus occurs in many breeding colonies, but the impact has not been quantified (Zonfrillo 2007, Carboneras et al. 2014). Chick predation by Red Deer Cervus elaphus on Rhum appears to be a local phenomenon (Wormell 1969), but with negligible effects on the global population. Reports suggest that considerable human exploitation continues in the Islands of Madeira, Azores and Faroes (Carboneras et al. 2014), with the legal harvest on the Faroes amounting to 1,000–5,000 chicks per annum (Thorup et al. 2014). The level of impact on the local populations is unknown, but harvesting is likely to be contributory to limiting population size, especially in the smaller colonies. Attraction to artificial light poses another potential threat, with grounded fledglings being recorded from e.g. the Canary Islands (Rodriguez and Rodriguez 2009), however the total number killed as a result of light pollution is thought to be negligible in proportion to the global population (Carboneras et al. 2014). Habitat destruction and fire-induced damage to breeding colonies in the Canary Islands is believed to impact the local population. The species is also vulnerable to oil spills (Votier et al. 2005), other types of marine pollution (Camphuysen et al. 2010), bycatch in longlines and gillnets (Žydelis et al. 2013), and collisions and displacement due to wind farms, although this is currently considered a low risk for this species (Bradbury et al. 2014).

Conservation actions

Conservation Actions Underway
The species is listed on Appendix II of the Bern Convention. It is covered by the EU Birds Directive as a migratory species. The following information refers to the species's European range only: It occurs in 20 marine Important Bird Areas including in the Faroe Islands, Iceland, Ireland, the U.K. and Spain. Within the EU it is listed in 53 Special Protection Areas in France, the United Kingdom, Ireland, Italy, Portugal and Spain. Current work in the United Kingdom and Ireland is tracking their seasonal movements and identifying foraging hotspots for protection.

Conservation Actions Proposed
The following information refers to the species's European range only: Identification and designation of important sites at sea. Management of invasive alien species within breeding colonies and monitoring and enforcement action (where appropriate) against human exploitation. Increase observer effort on board fishing vessels to monitor bycatch rates, and implementation where appropriate of bycatch mitigation measures.


Text account compilers
Bennett, S., Calvert, R., Ashpole, J, Ekstrom, J., Fjagesund, T., Butchart, S., Martin, R., Newton, P.

Recommended citation
BirdLife International (2023) Species factsheet: Puffinus puffinus. Downloaded from on 26/09/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from on 26/09/2023.