The Chatham Island Shag is a large seabird belonging to the cormorant family. It has a predominantly black plumage with a glossy appearance. During the breeding season, adults develop a white crest on their heads and have a distinct greenish sheen on their feathers. They have a long, slender neck, a sharp beak, and webbed feet.
Chatham Island Shag are endemic to the Chatham Islands, an archipelago off the east coast of New Zealand. They primarily inhabit the rocky coastlines, sea cliffs, and offshore islands of the Chatham Islands. They are often found near areas with rich marine resources, as they feed in the coastal waters.
Chatham Island Shag are piscivorous birds primarily feeding on fish. They are excellent divers and swimmers, using their streamlined bodies and webbed feet to navigate the water. They hunt for fish near the surface or dive underwater to catch their prey. They also feed on other small marine organisms like squid and crustaceans.
Chatham Island Shag breeds in colonies, often nesting on cliffs or rocky outcrops. They build nests using seaweed, twigs, and other materials, usually in protected crevices or ledges. The female lays a clutch of eggs, and both parents take turns incubating them. After hatching, the chicks are cared for and fed by both parents until they fledge.
The Chatham Island Shag is classified as endangered by the International Union for Conservation of Nature (IUCN). Their population is small and vulnerable to various threats, including habitat loss, disturbance at nesting sites, and predation by introduced mammals. Conservation efforts focus on protecting their breeding colonies, monitoring their populations, and controlling invasive species.
As seabirds, Chatham Island Shag does not have specific tree preferences. They primarily rely on coastal and marine habitats for their survival, including rocky cliffs, sea stacks, and offshore islands. These areas provide suitable nesting sites, access to marine food sources, and protection from predators.