With his orange bill, tipped in black and deeply forked tail, the "Forster's Tern" is so similar to the "Common Tern" (except that his wing tips are a frosty white color), that this bird was not recognized as a separate species until the 1800's. His black cap disappears in winter to be replaced by a distinctive black mark behind the eye. It is named for the German pastor-naturalist, who accompanied Captain Cook around the world in 1772.
Sometimes hovering briefly, the "Forster's Tern" mainly catches its prey by flying back and forth over the surface of the water, then diving directly into the it for a tasty fish dinner.
The "Forster's Tern" breeds in scattered colonies along the Atlantic Coast from Massachusetts to Georgia and the Coast of Texas. Also from Alberta and California inland to the Great Lakes.
Calls or song.
The "Forster's Tern" has a variety of sounds in its repertoire; one of the most common is a repeated, "kerr". During courtship, adults broadcast to their mates with brief, twangy and buzzing calls.
Population and distribution.
The "Forster's Tern" is the only tern restricted almost entirely to North America, and it avoids competition with the "Common Tern" for food and habitat by favoring marshy areas rather than sandy beaches. They winter along the southern California and Virginia coasts southward.
These terns build a platform of dried grass, lined with greener, softer ones, which they place on masses of dead marsh vegetation. Here the female lays three or four spotted buff eggs.