General
Gull-billed Tern: The lightest North American tern. Black cap that extends below the eyes and down the nape, and pale gray upperparts that are darker at the wingtips; short, stout black bill and long black legs; long wings with very long outer primaries.
Range and Habitat
Gull-billed Tern: During breeding season, they occur in the eastern and southern coastal United States. Also seen during the winter along the southern coastal United States. Its winter range extends to central coastal areas of South America. Breeding habitat includes sand, gravel, or shell beaches, or some grassy areas of coastal islands.
Breeding and Nesting
Gull-billed Tern: Monogamous; colonial or solitary. Often nest at periphery of other tern species' colonies. Nest on open ground, often concealed in debris among shells, built by both sexes; one to four pink buff to yellow eggs lightly spotted with dark brown. Incubation ranges from 22 to 23 days and is carried out by both sexes. Young fledge in 28-35 days. One brood per year.
Foraging and Feeding
Gull-billed Tern: Flies over farm fields or marshes to catch insects, its main diet. Over water, swoops to catch small prey; also eats frogs, crustaceans, and earthworms.
Vocalization
Gull-billed Tern: Call is "kay-WEK." Also raspy "ge-rek," or "kay-tih-DID." Alarm is rasping "aach."
Similar Species
Gull-billed Tern: Sandwich Tern has thinner wing, a black bill with a yellow tip, and a shorter crest.