Friday, May 23, 2008

Black Skimmers

Attractive yet comical in appearance, the black skimmer is one of our more interesting coastal birds. Identified by its black and white plumage, red feet and black-tipped, red bill, it is the only bird with a lower mandible that is longer than its upper bill. Resting on the beach, the skimmer cuts a low profile, with its long beak, short legs and long wings; in flight, its wing span is more than twice the length of its body.

Favoring remote, sandy beaches, black skimmers breed along the Atlantic and Gulf Coasts, from southern New England to the northern shores of South America; on the Pacific Coast, they are found from southern California to South America. Gregarious, they breed in large colonies, often in the company of of least terns, choosing flat beaches with little or no vegetation. Nesting occurs from late May through early July and three to five eggs are laid in a shallow depression, directly on the sand. Chicks are born with even mandibles, allowing them to pick food from the surface of the beach.

Adults are graceful and buoyant fliers, often moving about in synchronized flocks. When feeding, they are usually found alone or in small groups, skimming the surface with their lower mandible and then snapping the bill shut when they encounter prey; they prefer to feed on calm, coastal bays but may hunt along the shoreline if wave action is limited. Come autumn, the black skimmers of New England migrate to the south, wintering along the Southeastern and Gulf Coasts.