Double-crested Cormorant

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Common Name: Double-crested Cormorant
Scientific Name: Phalacrocorax auritus

Size: 28-35 inches (70-90 cm)

Habitat: North America; Summer Range: Widely distributed across North America. Breeds locally along all coasts and extensively in Florida, the center of continent, and along the Great Lakes and the St. Lawrence Seaway. Also in Mexico, Belize, the Bahamas, and Cuba. Winter Range: Winters along Pacific Coast from Alaska to Mexico; along the Atlantic and Gulf coasts from North Carolina to Belize, with smaller numbers northward to New Hampshire; and at inland sites along large rivers and lakes northward to Indiana. Found in diverse aquatic habitats, such as ponds, lakes, rivers, lagoons, estuaries, and open coastline; more widespread in winter.

Status: Least Concern. Global Population: 1,100,000 - 2,200,000 mature individuals. common and widespread throughout its range. Cormorant populations greatly decreased in the 19th and early 20th centuries from human persecution. They recovered after the 1920s, with an interruption in the recovery during the pesticide era of the 1950s and 1960s. The National Audubon Society considered it a species of special concern in 1972. Increases after the 1970s were explosive in some areas. Increasing cormorant populations have caused conflicts with people. Cormorants have been suggested as playing an important role in the collapse of some fisheries, although data to support these claims are sparse. Cormorants eat fish at fish farms, and recent legislation has been proposed to control cormorant numbers.

Diet: Predominantly fish; some other aquatic animals, insects, and amphibians.

Nesting: Sexes are alike. Nests are a large, often flat nest of sticks and other bulky items, including seaweed and flotsam. It is lined with grass or similar material and is placed in trees, on the ground, or on cliffs. Cormorants nest in colonies. Nests often are exposed to direct sun. Adults shade the chicks and also bring them water, pouring it from their mouths into those of the chicks. There are usually 3-4 unmarked pale blue eggs.

Cool Facts: While the cormorant uses sticks and other materials to make its nest, it frequently picks up junk, such as rope, deflated balloons, fishnet, and plastic debris to incorporate into the nest. Parts of dead birds are commonly used too. Large pebbles are occasionally found in cormorant nests, and the cormorants treat them as eggs.

Accumulated fecal matter below nests can kill the nest trees. When this happens, the cormorants may move to a new area or they may simply shift to nesting on the ground.

Found in Songbird ReMix Seabirds

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