What is a Roseate Tern?

The roseate tern is an elegant, long-tailed member of the tern family. It has a limited range along the North American coast, including a small part of Canada and states south to New York, with some colonies residing in the islands of the Caribbean. Other names for the roseate tern include gaviotina, sterne de dougall, palometa, and charran rosada.

The backs of roseate terns are pale gray, while their chests are white, and birds of both genders have black feathers on the tops of their heads and along their wingtips. Juvenile birds resemble adults, but have completely black heads and mottled patterns across their backs. Birds mature at between 13 and 16 inches (about 33 and 41 cm) and weigh between 3.2 and 4.9 oz (about 90 and 140 g). Their wingspan is about 30 inches (76 cm) from tip to tip. These gull-like birds are closely related to other members of the tern family, such as the common tern, the arctic tern, the least tern, and Forster's tern.

The tip of the short, pointed bill is black, and changes color based on the roseate tern's native region and the months of the year. In southern Caribbean birds, beaks turn almost entirely red in the breeding months of June and July, remaining up to half black for the rest of the year. Northern birds have beaks that are black until May, when they return to their breeding grounds. Their beaks turn red through June and July as they incubate their eggs, and turn back to black in August.

Changing beak colors coincide with the roseate tern's breeding season. The birds make their nests along coastlines; these nests can be as simple as a small pit in the sand lined with whatever the terns can find in the rocks or grasses they prefer. Each brood contains anywhere from one to five brown, spotted eggs, and the parents take turns incubating them until they hatch in approximately 20 days. Birds nest in colonies ranging from a handful to hundreds of pairs.

Close proximity to the coast allows the roseate terns convenient access to their primary foods, including small fish and the occasional invertebrate. Terns hunt by skimming above the surface of water and diving in when they spot a fish. The American sand lance is one of their preferred species of prey.

The roseate tern is considered a threatened species. Populations compete with each other over limited space, and many native nesting areas have been taken over by humans. Along with the human presence along the tern's beaches come other predators such as raccoons and dogs, which can easily destroy tern nests.