Forster's Tern (Birds of Alabama)

Forster's Tern

Sterna forsteri

Summary ⁵

The Forster's Tern (Sterna forsteri) is a member of the tern family Sternidae. It breeds inland in North America and winters south to the Caribbean and northern South America.

Sterna forsteri ⁶

A medium-sized (14-15 inches) tern, Forster’s Tern in summer is most easily identified by its solid black cap, deeply-forked tail, black-tipped orange bill, and pale wing tips. In winter, this species becomes duller on the head and face, becoming dark-billed and pale headed while retaining conspicuous black eye-patches. This species may be distinguished from the similarly-sized Common Tern (Sterna hirundo) by that species’ dark wing tips and (in winter) black hood. Male and female Forster’s Terns are similar to one another in all seasons. Forster’s Tern breeds in a number of widely-separated areas across North America, both inland (on the northern Great Plains and Great Basin region) and along the coast (on the Atlantic, Gulf, and Pacific coasts, as well as in the Great Lakes region). In winter, this species may be found along the coast from California and the Mid-Atlantic region south to Central America. Populations breeding in southern coastal areas generally migrate short distances, if at all. Forster’s Terns primarily breed in marshland habitats, being found both at inland freshwater marshes and at coastal salt marshes. In winter, this species may be found along the shoreline on sandy beaches, riverbanks, and mudflats. Forster’s Terns mainly eat small fish. Forster’s Terns may be most easily seen standing or walking along the shore or on the beach, where their pale wing tips and (in summer) black-tipped orange bill may be most apparent. With the aid of binoculars, it may also be possible to observe this species feeding by diving headfirst into the water. Forster’s Terns are most active during the day.

Threat Status: Least concern