Least Tern (Sternula antillarum) is the smallest (21-23 cm) North American tern and breeds in coastal areas of California, portions of the Atlantic Coast and Gulf Coast, and islands throughout the Caribbean. The interior population of least terns has only small, remnant colonies throughout their former range. Terns have been observed to breed at Bitter Lake National Wildlife Refuge in southeastern New Mexico. They nest on salt flats, sandbars, and sand dunes near water and eat fish and aquatic invertebrates.