Double-crested Cormorant (Phalacrocorax auritus)
Photo Credit: John J. Mosesso
Length: 30-36 in.
Habitat: coastal areas, lakes and rivers.
Of the 36 Cormorant species worldwide, 6 of them reside in North America, most along the seacoast.
The Double-crested Cormorant (Phalacrocorax auritus) is a goose-sized bird with a long neck and hooked bill. The adults are black and have a greenish sheen with orabeg bare skin on the face and throat. The crests for which these birds are named are so inconspicuous that they are generally not seen. Double-crested Cormorant are the most common and abundant along the atlantic Coast. They often fly in V-shape formations like Canada geese but with their necks characteristically kinked in flight.
Their plumage is not water repellant so they often bask in the sun, holding their wings open to aid drying their feathers and regulate body temperature. Even so, only the outer feathers become heavy and soaked ; an insulating layer beneath the external plumage protects them from chill when swimming underwtare. Cormorants swim low in the water and look very much like loons; cormorants, however, swim with their billes tipped up. This is an easy way to separate a cormorant from a loon.
Cormorants are gregarious birds and will hunt in small groups, flying low over the water searching for fish, their primary prey. When they locate a school of fish, they land on the water and plunge head first below the surface of the water where they swim by using wheir wings and short, webbed feet. Cormorant's eyes are both adapted to aerial and underwater vision. They have been known to dive 75 feet or more. Typically, they dive 5 or 25 feet deep, usually remaining submerged from 30 seconds to over a minute.
Nesting colonies can be in trees near water, on cliff edges or on the ground on islands. The birds rarely vocalize, except in the nesting colony uttering guttural croaks and grunts.
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