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.
Region
Chatham Islands, New Zealand
Typical Environment
Occurs around the main Chatham and Pitt islands and nearby islets such as The Sisters and The Forty-Fours. Breeding colonies are on low rocky stacks, sea cliffs, and small offshore islets exposed to strong swell. Birds forage in shallow coastal waters over rocky reefs and kelp forests, typically within a few kilometers of colonies. They dive to the seafloor to take prey over sand and reef substrates and roost on wave-washed ledges between bouts of feeding.
Altitude Range
Sea level to 100 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
A blue-eyed shag endemic to the remote Chatham Islands of New Zealand, it was formerly placed in Phalacrocorax but is now usually in Leucocarbo. It nests in dense colonies on offshore rock stacks and low islets and is highly sensitive to human disturbance. The species forages close to shore, diving for benthic fish and invertebrates among kelp beds. Major threats include disturbance at breeding sites, bycatch, and predation by introduced mammals.
The Chatham Islands shag is, as its name suggests, endemic to the Chatham Islands of New Zealand.
Temperament
colonial but wary of disturbance
Flight Pattern
strong direct flight with rapid wingbeats low over water
Social Behavior
Breeds in compact colonies on offshore stacks and islets, with pairs forming monogamous bonds for the season. Nests are built from seaweed and vegetation cemented with guano on ledges and flat rock surfaces. Chicks are altricial and are guarded closely, with both parents sharing incubation and chick-rearing duties.
Migratory Pattern
Resident
Song Description
Generally quiet away from colonies; at nests it gives low guttural grunts, hisses, and croaks. Courtship involves bill-clicking and display postures accompanied by soft calls.
Plumage
Predominantly pied: glossy black upperparts with clean white underparts and throat; some individuals show darker morphs. Breeding adults may show a short dark crest and white thigh patches. The bill is grey-horn and slender with a hooked tip.
Diet
Feeds mainly on small benthic fishes, along with cephalopods and crustaceans. It is a pursuit diver, using its feet and partially spread wings to propel itself underwater. Foraging dives are typically short but repeated, often in the vicinity of kelp beds and reef edges. Individuals may forage alone or loosely with conspecifics.
Preferred Environment
Shallow coastal waters, rocky reefs, and kelp forests near breeding colonies. Frequently forages within sheltered bays and channels but also along exposed coasts when conditions allow. Uses offshore rocks and ledges as resting and drying sites between foraging bouts.
