Roseate tern

The roseate tern occurs along coastal areas in both temperate and tropical areas throughout the world. The North Atlantic breeding population is located in the northeastern United States and southern Canada, from Nova Scotia to Long Island, New York. Historic nesting records range south to Virginia.

The roseate tern is a coastal species that nests on barrier islands and salt marshes. They forage over shallow coastal waters, inlets, and offshore seas. Nesting colonies are located above the high-tide line, often within vegetated dunes. Roseate terns nest at sites with more vegetative cover than other terns found in New Jersey.

Roseate terns mainly eat small fish. They hunt by hovering over water before diving head first to catch prey. They often forage over shallow waters and concentrate on large schools of baitfish that are schooled up from larger fish like bluefish.

In New Jersey, roseate terns return to their nesting areas in late April and early May. Where heavy predation pressure is absent, roseate terns exhibit a strong fidelity to their nest sites. This means that they return to the same nest sites year after year. Courting terns perform aerials displays and feed their mates to help establish pair bonds.

Roseate terns nest in colonies that often occur with other terns. Unlike some other terns, roseates prefer to nest within areas of dense vegetation, like sand dunes. They make a scrape in the sand where the female lays a clutch of one to two buff colored eggs. They have heavy brown streaking to help camouflage the eggs from being predated. The male and female incubate the eggs for 21 to 26 days. When a predator enters the breeding colony all of the terns take flight and bombard the intruder by dive bombing it and defecating on it. After the eggs hatch, both adults care for and feed the young. The young fledge when they are 22 to 33 days old. The adults continue to feed the young until they migrate south for the winter.

Roseate terns do not breed until they are three to four years old.

Prior to 1890, the roseate tern nested along the New Jersey coast, although it was not common. From the late 1800’s to the early 1900’s, roseate tern populations along the Atlantic Coast were greatly reduced as a result of the millinery trade, in which birds were killed to acquire plumes for women’s hats. The Migratory Bird Treaty Act of 1918, which afforded legal protection to all migratory birds, coupled with a change in fashion styles, reduced the pressure on roseate terns, enabling populations to reestablish and increase. Nesting roseate terns were observed at Hereford Inlet and Five Mile Beach in the 1930’s and at Brigantine in the 1940’s. However, by the 1950’s, populations again began to decline and continued to do so for several decades.

Breeding roseate terns were documented in New Jersey in the 1970’s, when nesting pairs occurred at Little Egg Inlet, Brigantine, Sandy Hook, Holgate, and Barnegat Bay. The last nesting pair in the state was recorded in 1980. Unchecked development and high levels of recreational activity along the barrier islands have resulted in habitat loss and disturbance to beach-nesting birds, attributing to the decline of this species.

Due to severe population declines in the state, the roseate tern was listed as a threatened species in New Jersey in 1979. Because of a drastic worldwide decline in its population, the roseate tern was reclassified as an endangered species in New Jersey in 1984. The U.S. Fish and Wildlife Service included the North Atlantic breeding population on its list of federally endangered species in 1987 because of declines resulting from human activity, gull competition, and predation. Depressed roseate tern populations are evident throughout other northeastern states, where the species is listed as endangered (Massachusetts, Connecticut, New York, Virginia), or threatened (Maine, New Hampshire).

Learn about the work being done to research and protect NJ’s beach nesting birds at our Beach Nesting Birds Project webpage.