[1] It is found in the eastern United States and Middle America, the Caribbean, Trinidad and Tobago, and in every mainland South American country except Bolivia and Paraguay, though rare in Chile.

The International Ornithological Committee (IOC) follows Efe et al. in part[4] and treats it as a species with two subspecies, the nominate T. a. acuflavidus (Cabot, S, 1847) and T. a. eurygnathus (Saunders, 1876).

[1] The American Ornithological Society and the Clements taxonomy have not yet accepted Efe et al. and treat those two taxa as subspecies of the Sandwich tern (T.

[10] Some authors treat subspecies T. a. eurygnathus as a separate species, the "Cayenne tern" but this has not been widely accepted.

Adults in breeding plumage have a black cap and a mostly white body with a pale gray back and sometimes a rosy flush on the underparts.

[13] The nominate subspecies of Cabot's tern breeds on the U.S. coast from Chesapeake Bay south and around the Gulf of Mexico to Belize, and on the Bahamas, the Greater Antilles, and other Caribbean islands.

It generally uses bare ground but will nest on prostrate vegetation or mats of purslane (Sporobolus virginianus).

It overwinters on sand beaches and sandbars, barrier islands, and reefs along coasts and also along the Panama Canal and short distances up rivers that empty into salt water.

[12] Cabot's tern is partially migratory, withdrawing from the northernmost part of its breeding range for winter.

Birds that overwinter on the Pacific coast of South America apparently cross from the Caribbean at the Isthmus of Panama.

Its diet is mostly fish, with members of families Ammodytidae, Atherinopsidae, Clupeidae, Engraulidae, and Sciaenidae identified as prey.

[12] Cabot's terns apparently court and form pairs during spring migration before reaching the nesting grounds.