Phalacrocoracidae – Cormorants & shags

We don’t need to drink water: all the water they require is provided by fish that they eat

Cormorants and shags are coastal birds that are supremely adapted to aquatic life. These birds are found near lakes, rivers, and along coastlines around the world, except for the central Pacific islands.

Cormorants and shags are exceptional divers. They hunt by diving from the surface and pursuing their prey underwater, propelling themselves with their strong webbed feet and steering with their short wings. Unlike many other water birds, cormorants and shags do not have fully waterproof feathers, which is an adaptation that reduces buoyancy and allows them to dive deeper and stay underwater longer. After a hunting session, these birds can be seen perching with their wings outstretched to dry their feathers in the wind and sun, a characteristic pose that is iconic to these species.

The diet of these birds consists mainly of fish, but they will also eat eels, water snakes, and even small crustaceans. Their fishing skills are so proficient that in some parts of the world, especially in Asia, fishermen have trained cormorants for fishing. These birds are fitted with a snare near the base of their throat, preventing them from swallowing larger fish, which the fishermen instead collect.

When it comes to breeding, cormorants and shags are quite versatile. Many species prefer to nest in colonies on cliffs or in trees, while others nest on the ground on islands free from predators. The nests are constructed with seaweed, twigs, and other debris. Both parents participate in all aspects of reproduction, from nest building and egg incubation to feeding and protecting the young chicks.

The social structure of cormorant and shag colonies is complex and includes a variety of vocalizations and displays, particularly during the breeding season. Their courtship displays are elaborate and can include mutual preening, bill fencing, and wing-waving.