Northern Prairie Wildlife Research Center
STATUS: Widespread and locally common.
HABITAT: Inhabits coastal areas, bays, estuaries, marine islands, freshwater lakes, ponds, rivers, sloughs, and swamps. (Only cormorant likely to be seen inland around freshwater lakes and rivers.) Has a pronounced preference for perching in trees, on rocks, buoys, or other objects that overhang or project from the water.
SPECIAL HABITAT REQUIREMENTS: Undisturbed nesting site and convenient, dependable food source within a foraging radius of 5 to 10 miles from roost or colony.
NEST: Nests in colonies of a few to 3,500 pairs on rocky islands, cliffs facing water, or in stands of live or dead trees in or near water. In the Northeast and along the Pacific Coast, nests on the ground, on rocky islands, or on cliffs. Inland and in Florida, usually nests in trees. Breeding colonies may be located from below sea level to over 5,600 feet.
FOOD: Captures food during dives in water, generally 5 to 25 feet deep but sometimes up to 72 feet deep. Prefers to hunt in water with a sandy bottom rather than over a rocky or gravelly bottom. Consumes primarily saltwater fish of little commercial value, plus freshwater yellow perch, bullheads, sticklebacks, carp, crappies, and sunfish. Also eats some salamanders, crustaceans, reptiles, mollusks, and sea worms.
REFERENCES: Palmer 1962, Stallcup in Farrand 1983a, Terres 1980.