Cormorants are a diverse group of aquatic birds that inhabit various watery environments across the globe. These birds possess unique adaptations that allow them to thrive in both marine and freshwater ecosystems. With over 40 distinct species, cormorants are widespread and often spotted near bodies of water.
Identifying Cormorants
Cormorants are medium to large-sized birds, weighing between 0.35 to 5 kilograms and having a body length ranging from 45 to 100 centimeters. Most species feature dark plumage, often appearing black with a metallic sheen that can include hints of blue, green, or purple. They possess a long, slender body, a distinctively long neck, and a medium-length tail.
Their long, thin bill is sharply hooked at the tip, well-suited for catching fish. Their feet are fully webbed, aiding their powerful swimming. Many cormorant species also display areas of bare, colored skin on their face and a visible gular pouch beneath the bill, which can be yellow, orange, or even blue, often becoming more vibrant during breeding season. Some species develop white patches on their thighs or heads during the breeding period.
Where Cormorants Live
Cormorants are found on every continent except Antarctica and throughout nearly every country. They are primarily aquatic birds, commonly inhabiting both freshwater and saltwater environments, including coastlines, estuaries, lakes, rivers, and reservoirs.
These adaptable birds can be seen in various climates, from tropical regions to temperate zones. While some species are predominantly coastal, nesting on cliffs or rocky shorelines, others have successfully colonized inland waters, establishing colonies in trees or on flooded gravel pits.
How Cormorants Hunt and Live
Cormorants are fish-eaters, consuming a diet of fish, typically less than 20 cm in length. They are divers, propelling themselves underwater primarily with their powerful webbed feet, though some species may also use their wings for additional propulsion. These birds can dive to considerable depths, with some species observed reaching depths of up to 45 meters, and even up to 80 meters for certain imperial shags.
After diving, cormorants frequently exhibit perching with their wings outstretched. This posture serves to dry their feathers, which are not fully waterproof, unlike those of many other waterbirds. This characteristic allows their plumage to become waterlogged, reducing buoyancy and enabling them to dive deeper and more efficiently to pursue prey. Once out of the water, they spread their wings to allow air and sun to dry their feathers before resuming flight or further activities. Cormorants are social birds, often forming large communal roosts and nesting in colonies.