Least Tern
Sternula antillarum

Physical Description

• A small bird with narrow, pointed wings and sharp, bracket-shaped tail.
• Breeding adults: a black crown and white forehead. Thin yellow legs and a thin yellow bill. Yellow bill often has black tip. White feathers and gray wings, wings can have black edges, visible in flight..
• Non-breeding adults: all adults keep breeding coloration.
• Juveniles: Very small, with white belly and barred or scaly looking back and wings with light brown coloration. Crown is light brown or can be partially black. Darker bill than adults.

Range

• Breeding: the Caribbean, the United States (both coastal and major rivers), coastal Mexico, down to northern South America.
• Migrating: migrate to central U.S. to breed in major rivers.

Habitat

• Found along seacoasts, bays, beaches, lagoons, estuaries, rivers, and lakes.
• Breed on sandy and gravelly beaches or on lakeshores and riverbanks.

Diet

• Aerial divers that plunge for prey.
• Small fish, crustaceans, insects, small mollusks, worms.

Predators

• Cats, dogs, coyotes, crows, skunks, foxes, and raccoons all prey on tern nests.
• Burrowing owls, peregrine falcons, and American kestrels feed on adult terns.

Interesting Facts

• They are the smallest tern in North America, hence the name Least Tern.
• The oldest recorded least tern was 24 years old.
• Least terns nest on the ground. Their population declined by 88% between 1966 and 2015, mainly due to humans encroaching on their nesting habitat. Never disturb a nest if you see one in the ground on the beach! 

Sources: AllAboutBirds.org; Audobon Field Guide; American Bird Conservancy; Los Padres ForestWatch

Photo: Thomas A. Blackman