Month: May 2011

Sea Bird – Double-crested Cormorant

double-crested-cormorant

Double-crested Cormorant (Phalacrocorax auritus) – Double-crested Cormorants are common on the coasts of North America. They are found in the Pacific from the Aleutian Islands to Mexico. The Double-crested Cormorant is the most abundant species of cormorant found in Oregon. They are colonial nesters on offshore rocks, cliff ledges, trees, and islands. The limbs of the trees used for nesting eventually decay and die from accumulations of guano. Nests are built mainly from sticks and are reused year after year. Laying begins in mid-March, consisting of three to four eggs. Incubation lasts 25 – 29 days and is done by both sexes. Altricial young fledge at five to six weeks. Double-crested Cormorants feed on bottom dwelling fish away from shore and the young is fed by regurgitation. In order to make deep sea water dives, cormorants have the ability to wet the outer layer of their feathers thus reducing buoyancy allowing them to pursue prey further down in the water column.