Caspian Tern (Sterna caspia)

County List:

Rule:

Mixed Forested/Nonforested or Nonforested Landscapes

      Lake
   adjacent to:
      Shorelines/Mudflats

Habitat List:

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Literature:

Habitat: While foraging habitat may be almost any large body of water, Caspian Tern breeding habitat is specific. Nesting is on open pebble or sandy beaches with islands apparently preferred, because eggs and small young are vulnerable to predation. The typical nest is a shallow depression near the water line. Rarely, caspians nest directly atop limestone or in unlined nests in low grass.

Currently, the major predator of the Caspian Tern is the Herring Gull, which kills sizable numbers of chicks. In addition, both Ring-billed Gulls and Double-crested Cormorants compete strongly for nesting spaces.

Habitat: Large lakes, coastal waters, beaches, bays. Found on both fresh and salt water, favoring protected waters such as bays, lagoons, rivers, lakes, not usually foraging over open sea. Inland, more likely on large lakes than on small ponds. Nests on open ground on islands, coasts.

Diet: Mostly fish. Often concentrates on a few abundant fish species in a given locale (for example, alewife on Great Lakes). Also eats insects, sometimes eggs or young of other birds.

Nest: Site is on bare ground, among driftwood or debris, perhaps sometimes on floating mats of dead vegetation. Nest is shallow depression, sometimes with rim or lining of debris.