Chatham Islands Shag Leucocarbo onslowi

Family: Phalacrocoracidae (Cormorants)

Authority: (Forbes, 1893)

Red List Category

Criteria: A2bcde+3bcde+4bcde

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Justification of Red List category
Surveys in 2003 and 2011 indicated that this species is in decline. This, in combination with the extremely small area occupied by its breeding colonies, which suffer disturbance from agriculture and feral mammals, qualifies the species as Critically Endangered.

Population size: 710 mature individuals

Population trend: decreasing

Extent of occurrence (breeding/resident): 8,600 km2

Country endemic: yes

Land-mass type - oceanic island
Realm - Oceanic
IUCN Ecosystem -- Marine biome

Recommended citation
BirdLife International (2023) Species factsheet: Leucocarbo onslowi. Downloaded from on 02/12/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from on 02/12/2023.