// BIRDS
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Least Tern
Sternula antillarum
Description The least tern is widely distributed in coastal areas and major inland waterways throughout much of the Americas and the Caribbean (Thompson et al., 1997). This species has three breeding populations and their distributions within those populations are localized and not continuous. The California least tern breeds along the Pacific Coast from California to western Mexico, the eastern (or coastal) least tern breeds along the Atlantic and Gulf coasts from New England to the Caribbean and Central America, and the interiLeast tern on a beach. Credit: Dennis Donohue / Shutterstock or least tern breeds along major rivers and watersheds in the central U.S. (e.g., Mississippi, Arkansas and Red River (1 ounce). Their wingspan is about 51 centimeters watersheds) (Robertson & Woolfenden, 1992; Lott, (20 inches). 2006). All populations are migratory, moving to Least terns arrive at their breeding grounds from more tropical coastal waters in the Western Hemisphere from Central America south to the west late April to mid-May, forming colonies that can coast of Peru and to southern Brazil. Least terns have well over 1,000 pairs of birds. Peak nesting from two of the three populations are seasonally is from mid-May through July. By late August and present on the Gulf Coast (Map 29). Eastern least early September, least terns leave their breeding terns breed in colonies along the coast in each of grounds and migrate to wintering areas. The minimum estimate for the least tern population from the U.S. Gulf states and in Mexico and Cuba, whereTexas to the Florida panhandle is about 11,400 to as interior least terns pass through the region during 12,200 (Lott, 2006). migration and occasionally winter on the Gulf Coast. The preferred nesting habitats of least terns are sandy beaches, yet riverine sandbars, mudflats and even gravel roofs are also suitable nesting areas. The species is a plunge diver, feeding on small fish, but also crustaceans and insects in shallow-water habitats, such as bays, lagoons, estuaries, river and creek mouths, tidal marshes, and ponds (Thompson et al., 1997). Least terns are 20 to 23 centimeters (8 to 9 inches) in length and weigh approximately 28 grams
Any interior (>50 km from the coast) nesting least tern is listed as endangered under the federal Endangered Species Act (USFWS, 50 Fed. Reg. 21792). Although the eastern least tern population is not federally listed, they are listed as a Species of Concern in Mississippi and Threatened in Florida, and are considered a Species Requiring Management Attention by the Southeast United States Regional Waterbird Conservation Plan (Hunter et al., 2006). Continued habitat loss, due to human activities, as well as sea level rise and erosion, especially
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