It is thought that the loss of flight in this species is the result of a long period of evolution on isolated, predator-free islands, as well as the fact that they forage in a very small area (7). Unlike penguins, which ‘fly’ through the water using their flipper-like wings, the flightless cormorant propels itself by kicking its strongly-built legs (7).
The flightless cormorant feeds on octopuses, eels and bottom-dwelling fishes, which it hunts for by making pursuit-dives (3). All cormorants are aquatic predators, but their feathers are not waterproof. A behaviour characteristic of the family is to adopt a stance after emerging from the water in which the wings are held open in order to dry the feathers. Flightless cormorants retain this behaviour, and are commonly seen holding their small ragged wings at their sides (7).
Nesting tends to take place during the coldest months (July-October), when marine food is at its most abundant and the risk of heat stress to the chicks is decreased (2). At this time, breeding colonies consisting of around 12 pairs form (3). The courtship behaviour of this species begins in the sea; the male and female swim around each other with their necks bent into a snake-like position. They then move onto land. The bulky seaweed nest, located just above the high-tide mark, is augmented with ‘gifts’ including pieces of flotsam such as rope and bottle caps, which are presented to the female by the male (3) (7). Two to three whitish eggs are laid; they are incubated by both parents (3) (7). After the chicks hatch, the parents share the duties of brooding and feeding (7). If food is plentiful, the female may leave the male to continue to care for the chick as it approaches independence; she will then produce a second brood with another male (7). This high breeding potential allows the population to quickly recover from declines in numbers (7).