Cormoran

Phalacrocoracidae

Cormoran - Nueva Venecia, Magdalena, Colombia

Quick Facts

Migratory
  • Scientific Name: Phalacrocorax carbo
  • Spanish Name: Cormorán grande
  • Family: Phalacrocoracidae
  • Known Nicknames: Great Cormorant, Great Black Cormorant, Black Shag, Large Cormorant
  • Average Length: 70–102 cm / 28–40 in
  • Average Weight: 1.5–5.3 kg / 3.3–11.7 lb
  • Wingspan: 121–160 cm / 48–63 in
  • Key Feature: Hooked upper mandible and characteristic wing-spreading posture to dry non-waterproof feathers
  • Primary Diet: Primarily Piscivore (Fish)
  • Range: Widespread across Europe, Asia, Africa, Australia, and the Atlantic coast of North America
  • Habitat: Coastal waters, estuaries, salt marshes, and large freshwater lakes or rivers
  • Social Structure: Highly Social, Colonial
  • Nesting/Breeding: Cliffs, rocky islets, or tall trees near water bodies
  • Conservation Status: Least Concern (LC)
  • Population Trend: Increasing

The Great Cormorant (*Phalacrocorax carbo*) is a striking and highly adaptable water bird, easily recognized by its iridescent black plumage, long serpentine neck, and a powerful bill tipped with a sharp hook. A master of the aquatic hunt, it possesses the unique characteristic of having feathers that are not fully waterproof; while this requires the bird to spend hours perched with its wings dramatically outstretched to dry, it also reduces buoyancy, allowing it to dive deeper and more efficiently than most other avian predators. Beyond its piercing emerald-green eyes and white facial patches, the cormorant is a marvel of evolution, using its large webbed feet to propel itself through both coastal and inland waters with remarkable speed in pursuit of fish. This blend of prehistoric elegance and specialized predatory skill has made the Great Cormorant one of the most successful and widely distributed diving birds in the world.

Fun Facts

Unlike most waterbirds, Great Cormorants lack fully waterproof feathers, a unique adaptation that reduces buoyancy and allows them to dive to impressive depths of up to 45 meters. This trait leads to their iconic "sun-worshipping" behavior, where they stand with wings outstretched to dry off after a hunt. They are also known for their striking emerald-green eyes and a specialized hooked beak designed for snatching slippery prey. Their fishing efficiency is so remarkable that they have been partnered with humans for centuries in traditional Asian cormorant fishing, where they are trained to bring catches back to boats.

Habitats & Distribution

This species boasts a vast global distribution, inhabiting nearly every continent except South America and Antarctica. Its range extends across Europe, much of Asia, and Africa, while also reaching the coasts of Australia and New Zealand. In North America, it is primarily found along the eastern seaboard. While many populations are sedentary, those breeding in northern latitudes often migrate southward to find ice-free coastal or inland waters during the winter months. Highly adaptable, it thrives in a diverse array of aquatic environments ranging from coastal marine settings to inland freshwater systems. It is frequently observed in estuaries, salt marshes, and along rocky shorelines, but is equally at home on large lakes, rivers, and reservoirs. For nesting and roosting, it requires proximity to productive fishing waters with access to elevated or isolated sites such as cliffs, rocky outcrops, or tall trees, which provide protection from predators and a place to dry its plumage.

Behaviours & Reproduction

These highly social birds are known for their gregarious nature, often living in large colonies and engaging in communal fishing. A distinctive behavior is their habit of standing with wings spread wide to dry their plumage, which lacks the full waterproofing of other waterbirds to facilitate deeper diving. Within their colonies, they maintain a structured social environment, using specific vocalizations and posturing to defend small nesting territories against neighbors. During the breeding season, they form seasonally monogamous pairs through elaborate courtship displays, such as rhythmic wing-waving and neck-stretching. They construct bulky nests from sticks and seaweed, typically situated on coastal cliffs or in tall trees. Both parents contribute equally to the reproductive process, sharing duties for incubating the eggs and feeding the altricial chicks through regurgitation until they are ready to fledge.

Diet

The Great Cormorant is a highly efficient and opportunistic predator with a diet consisting almost exclusively of fish, ranging from bottom-dwelling species like eels and flatfish to surface-swimmers such as perch, roach, and carp. These birds are remarkable underwater hunters, utilizing their powerful webbed feet to dive to depths often exceeding ten meters in search of prey, which they seize with a specialized hooked beak. An intriguing aspect of their physiology is that, unlike many other water birds, their feathers are not fully waterproof; this lack of buoyancy actually helps them sink faster and hunt more effectively at depth. On average, an adult cormorant consumes between 400 and 700 grams of fish daily, and like birds of prey, they regurgitate pellets containing indigestible fish bones and scales. Furthermore, while they often hunt alone, they are known to engage in sophisticated communal fishing, where large flocks coordinate their movements to herd schools of fish into shallow waters for easier capture.

Colors

The Great Cormorant features predominantly black plumage with a characteristic metallic green or bronze sheen. During the breeding season, adults display prominent white patches on their cheeks and thighs, alongside a vivid yellow gular pouch at the base of the bill. Juveniles exhibit more muted brownish-grey tones with pale underparts for camouflage, while all adults possess striking emerald-green eyes.