Least Tern

Sterna antillarum

Order CHARADRIIFORMES - Family LARIDAE - Subfamily Sterninae

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1. Cool Facts
2. Description
3. Similar Species
4. Sound
5. Range
6. Habitat
7. Food
8. Behavior
9. Reproduction
10. Conservation Status
11. Other Names

The smallest of American Terns, the Least Tern is found nesting on sandy beaches along the southern coasts of the United States and up the major river systems far into the interior of the continent.

Cool Facts

• The Least Tern prefers sandy beaches for nesting, but it will use a flat gravel roof of a building. On sunny days the hot tar showing through the gravel can burn the feet of chicks or become stuck in their down.

Description

• Size: 21-23 cm (8-9 in)
• Wingspan: 48-53 cm (19-21 in)
• Weight: 30-45 g (1.06-1.59 ounces)

Small tern. During breeding, black cap ending at white forehead. Short white eyestripe. Bill yellow with black tip. Back light gray. Underside white. Black leading edge to wing. In nonbreeding plumage has black eyestripe extending to back of head, white top of head, and black bill.

Sex Differences

Sexes look alike.

Immature

Juvenile with U-shaped marks across back. Immature resembles winter adult.

Similar Species

• Winter Black Tern has darker gray wings and tail.

Sound

Alarm call a sharp "zwreep." Also a high-pitched "kee-zink, kee-zink."

»listen to songs of this species

Range

Summer Range

Breeds along coasts from central California and southern Maine southward to Mexico. Also along Missouri, Ohio, and Missippippi Rivers to Montana, Kentucky, and Missouri, and other scattered inland locations in to New Mexico, Texas, Colorado, and Nebraska. Also in Mexico, northern Central America, and Caribbean.

Winter Range

Winters along coasts from Mexico southward to southern South America.

Habitat

Seacoasts, beaches, bays, estuaries, lagoons, lakes and rivers, breeding on sandy or gravelly beaches and banks of rivers or lakes, rarely on flat rooftops of buildings.

Food

Small fish. Some invertebrates.

Behavior

Foraging

Plunges into water from flight; may hover briefly before plunging.

Reproduction

Nest Type

Shallow scrape in sand, soil, or pebbles.

Clutch Size

Usually 1-3 eggs.

Condition at Hatching

Downy, eyes open, able to walk but stays in nest.

Conservation Status

Although widespread and common in places, its favored nesting habitat is prized for human recreation, residential development, and alteration by water diversion, which interfere with successful nesting in many areas. It is classified as "Threatened," "Endangered," or "species of concern" for most states because of loss of nesting habitat. Interior Population federally listed as "Endangered" in 1985.

Other Names

Petite Sterne (French)
Charrán mínimo, Golondrinita marina, Gallito (Spanish)

Sources used to construct this page:

Thompson, B. C., J. A. Jackson, J. Burger, L. A. Hill, E. M. Kirsch, and J. L. Atwood. 1997. Least Tern (Sterna antillarum). In The Birds of North America, No. 290 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists? Union, Washington, D.C.