Terns (Sternidae)

Least Tern (Sterna antillarum) - HBW 3, p. 657

French: Petite Sterne German: Amerikanische Zwergseeschwalbe Spanish: Charrancito Americano

Taxonomy: Sternula antillarum Lesson, 1847, Guadeloupe, Lesser Antilles.
Forms superspecies with S. albifrons, S. saundersi, S. superciliaris and S. lorata. Long considered a race of S. albifrons, but recently separated mainly on basis of voice. Currently accepted polytypic arrangement disputed by findings of morphometric and biochemical analyses. Proposed form mexicana for birds of Pacific coast of Mexico is not separable. Three subspecies recognized.

Subspecies and Distribution:

browni Mearns, 1916 - C California (San Francisco Bay) to Baja California and W Mexico; winters mostly in Central America.
athalassos Burleigh & Lowery, 1942 - inland rivers in C North America, from N Great Plains to N Louisiana and Texas; winters to N Brazil.
antillarum (Lesson, 1847) - Bermuda, and Maine S to Texas (including lower Rio Grande Valley) and Honduras, and on through Caribbean to N Venezuela; winters to N Brazil.