Catharacta skua 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Charadriiformes Stercorariidae

Scientific Name: Catharacta skua
Species Authority: (Brünnich, 1764)
Regional Assessments:
Common Name(s):
English Great Skua
French Grand Labbe
Stercorarius skua Brünnich, 1764
Stercorarius skua skua AOU checklist (1998 + supplements)
Stercorarius skua skua Cramp and Simmons (1977-1994)
Taxonomic Source(s): del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Lynx Edicions BirdLife International.
Taxonomic Notes: Catharacta skua (del Hoyo and Collar 2014) was previously placed in the genus Stercorarius.

Catharacta skua,
C. antarctica and C. maccormicki (Sibley and Monroe 1990, 1993), cross-regional species, are retained as separate species contra Christidis and Boles (1994) and Turbott (1990) who include lonnbergi and antarctica as subspecies of C. skua and AERC TAC (2003) who include C. maccormicki as a subspecies of C. skua.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2012
Date Assessed: 2012-05-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Facilitator/Compiler(s): Butchart, S., Calvert, R. & Ekstrom, J.
Although this species may have a small range, it is not believed to 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 population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to 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.
Previously published Red List assessments:
2009 Least Concern (LC)
2008 Least Concern (LC)
2004 Least Concern (LC)
2000 Lower Risk/least concern (LR/lc)
1994 Lower Risk/least concern (LR/lc)
1988 Lower Risk/least concern (LR/lc)

Geographic Range [top]

Range Description: The Great Skua breeds in Iceland, Norway, Svalbard (to Norway), the Faroe Islands (to Denmark), the Scottish islands and a few on mainland Scotland. It is a migratory species, normally wintering off the Atlantic coast of France and the Iberian Peninsulas, but juveniles can reach as far as Cape Verde, the coast of Brazil, areas of the Caribbean and small numbers also winter on the Grand Banks of Newfoundland (Canada) (del Hoyo et al. 1996).
Countries occurrence:
Algeria; Antigua and Barbuda; Austria; Barbados; Belgium; Belize; Brazil; Bulgaria; Canada; Cape Verde; Colombia; Denmark; Dominica; Egypt; Faroe Islands; France; French Guiana; Germany; Gibraltar; Greenland; Guyana; Iceland; Ireland; Italy; Libya; Martinique; Mauritania; Montserrat; Morocco; Netherlands; Norway; Panama; Portugal; Puerto Rico; Russian Federation; Saint Kitts and Nevis; Saint Lucia; Saint Pierre and Miquelon; Saint Vincent and the Grenadines; Slovakia; Spain; Suriname; Svalbard and Jan Mayen; Sweden; Tunisia; United Kingdom; United States
Bermuda; Côte d'Ivoire; Croatia; Cuba; Czech Republic; Finland; Ghana; Greece; Guadeloupe; Hungary; Israel; Latvia; Liberia; Lithuania; Luxembourg; Malta; Montenegro; Nigeria; Poland; Romania; Senegal; Serbia (Serbia); Slovenia; Switzerland; Turkey
Present - origin uncertain:
Anguilla; Cyprus; Gambia; Guinea; Guinea-Bissau; Lebanon; Sierra Leone; Syrian Arab Republic; Trinidad and Tobago; Venezuela, Bolivarian Republic of; Virgin Islands, British; Virgin Islands, U.S.; Western Sahara
Continuing decline in area of occupancy (AOO): Unknown
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 16100
Continuing decline in extent of occurrence (EOO): Unknown
Extreme fluctuations in extent of occurrence (EOO): No
Continuing decline in number of locations: Unknown
Extreme fluctuations in the number of locations: No
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: The breeding population, which is confined to Europe, is estimated to number 16,000-16,000 breeding pairs, equating to 48,000-48,000 individuals (BirdLife International 2004).

Trend Justification:  The population is suspected to be stable in the absence of evidence for any declines or substantial threats.
Current Population Trend: Stable
Additional data:
Continuing decline of mature individuals: Unknown
Extreme fluctuations: No Population severely fragmented: No
Continuing decline in subpopulations: Unknown
Extreme fluctuations in subpopulations: No All individuals in one subpopulation: No

Habitat and Ecology [top]

Habitat and Ecology: This marine species avoids land during migration and winter, aggregating in winter in areas where it can scavenge from fisheries. It has a hugely varied diet owing to be being a highly opportunistic feeder. Individuals regularly show individual specialisations in diet and feeding with some colony-specific learning. Breeding begins in May, and it is loosely colonial but highly territorial, breeding on islands on flat ground with some vegetation cover, usually avoiding human contact. Most birds breed within 1 km of their birth place (del Hoyo et al. 1996).
Systems: Terrestrial; Marine
Continuing decline in area, extent and/or quality of habitat: Unknown
Generation Length (years): 17.5
Movement patterns: Full Migrant
Congregatory: Congregatory (and dispersive)

Citation: BirdLife International. 2012. Catharacta skua. The IUCN Red List of Threatened Species 2012: e.T22694160A38922105. . Downloaded on 25 November 2015.
Disclaimer: To make use of this information, please check the <Terms of Use>.
Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided