Chatham Shag
Leucocarbo onslowi
- Critically endangered
- Card rarity: Legendary
- Birds

The Chatham Islands shag, also known as the Chatham shag, is a species of bird in the cormorant and shag family, Phalacrocoracidae. It is endemic to the Chatham Islands of New Zealand. For a long time the species was placed in the genus Phalacrocorax; today it is mostly placed with the other blue-eyed shags of New Zealand and Antarctica in the genus Leucocarbo. Its closest relative is the Otago shag of South Island.
Classification
- Class
- Aves
- Order
- Suliformes
- Family
- Phalacrocoracidae
- Genus
- Leucocarbo