South Polar Skua Catharacta maccormicki


Taxonomic note
Catharacta maccormicki (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.

Taxonomic source(s)
Christidis, L. and Boles, W.E. 2008. Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, Australia.
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. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: #
Turbott, E.G. 1990. Checklist of the Birds of New Zealand. Ornithological Society of New Zealand, Wellington.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2018 Least Concern
2016 Least Concern
2012 Least Concern
2009 Least Concern
2008 Least Concern
2004 Least Concern
2000 Lower Risk/Least Concern
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status full migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 13,600,000 medium
Extent of Occurrence non-breeding (km2) 23,300,000 medium
Number of locations -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 6000-15000 poor estimated 2009
Population trend Stable suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations - - -
Percentage in largest subpopulation - - -
Generation length (yrs) 17.1 - - -

Population justification: The population is placed in the band 10,000-19,999 individuals, equating to 6,667-13,333 mature individuals, rounded here to 6,000-15,000 mature individuals.

Trend justification: The population is suspected to be stable in the absence of evidence for any declines or substantial threats.

Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Antarctica N Extant Yes
Antigua and Barbuda N Extant Yes
Argentina N Extant Yes
Australia V Extant Yes
Barbados N Extant Yes
Bermuda (to UK) V Extant Yes
Bouvet Island (to Norway) U Extant
Brazil N Extant Yes
Canada N Extant Yes
Chile N Extant Yes
Comoros V Extant Yes
Costa Rica N Extant Yes
Dominica N Extant Yes
Ecuador V Extant Yes
Egypt V Extant Yes
Falkland Islands (Malvinas) N Extant Yes
Fiji V Extant Yes
French Guiana N Extant Yes
Greenland (to Denmark) V Extant Yes
Guadeloupe (to France) N Extant Yes
Guatemala U Extant Yes
India V Extant Yes
Indonesia V Extant Yes
Israel V Extant Yes
Japan N Extant Yes
Jordan V Extant Yes
Kenya V Extant Yes
Maldives N Extant Yes
Martinique (to France) N Extant Yes
Mauritania N Extant Yes
Mauritius V Extant Yes
Mexico N Extant Yes
Micronesia, Federated States of N Extant Yes
Montserrat (to UK) N Extant Yes
Morocco N Extant Yes
Mozambique N Extant Yes
Namibia N Extant Yes
New Zealand N Extant Yes
Oman V Extant Yes
Palau U Extant Yes
Panama N Extant Yes
Peru N Extant Yes
Portugal V Extant Yes
Senegal N Extant Yes
Seychelles N Extant Yes
Somalia V Extant Yes
South Africa N Extant Yes
South Georgia & the South Sandwich Islands N Extant Yes
Sri Lanka V Extant Yes
St Kitts and Nevis N Extant Yes
St Lucia N Extant Yes
St Pierre and Miquelon (to France) N Extant Yes
St Vincent and the Grenadines N Extant Yes
Suriname N Extant Yes
Trinidad and Tobago N Extant Yes
USA N Extant Yes
Virgin Islands (to UK) U Extant Yes
Virgin Islands (to USA) U Extant Yes
Yemen V Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Antarctica Ryder Bay Islands
Antarctica Cierva Point and offshore islands
Antarctica Avian Island
Antarctica Litchfield Island
Antarctica Half Moon Island
Antarctica Potter Peninsula, King George Island
Antarctica Point Hennequin, King George Island
Antarctica Lagotellerie Island
Antarctica Svarthamaren
Antarctica Hop Island, Rauer Islands
Antarctica Haswell Island
Antarctica Cape Adare
Antarctica Possession Island
Antarctica Edmonson Point
Antarctica Cape Washington
Antarctica Inexpressible Island
Antarctica Depot Island
Antarctica Gregory Island
Antarctica Dunlop Island
Antarctica Blue Glacier to Cape Chocolate
Antarctica Dailey Islands
Antarctica Rocky Point, Ross Island
Antarctica McDonald Beach, Cape Bird
Antarctica Caughley Beach, Cape Bird
Antarctica Cape Crozier, Ross Island
Antarctica Beaufort Island
Antarctica Franklin Island southwest
Mauritania Canary current shelf-break (south)
Senegal Northern Senegal shelf break
Morocco Canary current shelf-break (north)

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Marine Coastal/Supratidal Sea Cliffs and Rocky Offshore Islands major breeding
Marine Intertidal Rocky Shoreline major breeding
Marine Intertidal Tidepools major breeding
Marine Neritic Macroalgal/Kelp suitable resident
Marine Neritic Pelagic major resident
Marine Neritic Seagrass (Submerged) suitable resident
Marine Neritic Subtidal Loose Rock/pebble/gravel suitable resident
Marine Neritic Subtidal Rock and Rocky Reefs suitable resident
Marine Neritic Subtidal Sandy suitable resident
Marine Neritic Subtidal Sandy-Mud suitable resident
Marine Oceanic Epipelagic (0-200m) suitable non-breeding
Marine Oceanic Mesopelagic (200-1000m) suitable non-breeding
Rocky areas (eg. inland cliffs, mountain peaks) suitable breeding
Altitude   Occasional altitudinal limits  

Recommended citation
BirdLife International (2023) Species factsheet: Catharacta maccormicki. Downloaded from on 08/02/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from on 08/02/2023.