Roseate Tern

The roseate tern (Sterna dougallii) is found throughout the world. The North Atlantic subspecies, Sterna dougallii dougallii, is divided into two populations in North America because they breed in two discrete areas and rarely mix. The Northeastern population, federally listed as endangered, breeds on coastal islands from Eastern Canada, in Nova Scotia and Quebec, to New York. The federally listed threatened Caribbean population breeds on islands in the Caribbean Sea from the Florida Keys to the Lesser Antilles. Both populations winter on the north and east coasts of South America.

In 1936, Edward Howe Forbush wrote in Birds of America that the “Roseate tern is the embodiment of symmetry and grace – its flight the poetry of motion. Its elegant form tapers and swells in lines of beauty. Its lustrous plumage reflects the yellow rays of the sun and the pale refracted light of sea and sands in evanescent pink and rosy tints.”

Unfortunately, the bird’s beauty led to its decline as hunters shot them indiscriminately to decorate hats in the late 1800s. Since the 1930s, the species began to rebound when hunting was banned and many of its breeding colonies were protected. Nevertheless, the two populations remain small and vulnerable to extirpation because many of their breeding colony sites are no longer suitable for nesting. This lack of suitable nesting is due to the combined negative impacts from sea level rise, predation and human development.

More than 90 percent of the Northeastern population is now limited to three major breeding colonies, including one off of Long Island, New York which hosts more than 2000 breeding pairs, and two islands that are located in Buzzards Bay, Massachusetts and hosts more than 2000 breeding pairs combined. The entire Northeastern population was estimated at a little more than 4600 breeding pairs in 2019.

The most recent information known on the Caribbean roseate tern population include colonies in various cays in Florida, Puerto Rico, southwest cays, U.S. Virgin Islands and the British Virgin Islands which host more than 1700 breeding pairs. The most recent surveys from 2019 and 2021 document that Florida has an estimated 39 and 50 breeding pairs respectively. A 2018 survey of Puerto Rico documented more than 800 breeding pairs. U.S. Virgin Islands surveys in 2018 and 2019 documented 836 and 462 breeding pairs. Surveys in 2018 and 2019 in the British Virgin Islands documented 80 and 227 breeding pairs respectively. These numbers do not include other Caribbean Islands that may host roseate breeding sites.