Bridled Tern (Onychoprion anaethetus)

The Bridled Tern is a bird of warm tropical and subtropical waters. In North America, they are most commonly seen in warm waters off the coast of the southeastern United States, and small numbers have nested in southern Florida in recent decades. They also can be found throughout the Caribbean, the west coast of Africa, the Middle East, southeast Asia, and the Australia region. They are similar to the Sooty Tern, but Bridled Terns are slightly smaller and not as dark on the wings and back.

Habitat

Found on islands in tropical and sub-tropical waters when breeding, preferring islands with suitable shelter for nest sites, such as rocky areas or shrubs. At other seasons, found in and around warm waters, typically relatively close to shore rather than far out to sea.

Diet

The Bridled Tern feeds primarily on small fish, squid, and marine crustaceans captured at or near the ocean surface. It typically forages by dipping to the water's surface or making shallow plunge-dives and often feeds over schools of predatory fish that drive prey toward the surface.

Behavior

The Bridled Tern is a highly pelagic seabird that spends much of its life over tropical and subtropical oceans. It usually forages alone or in small groups, skimming or dipping to capture fish and squid from the water's surface. During the breeding season, it nests in colonies on remote islands, cliffs, rocky ledges, and coastal islets, where adults remain strongly attached to nesting territories.

Nesting

The nest of a Bridled Tern is a depression on the ground without any lining, placed in the shelter of a shrub or rock. The female lays a single egg, and both parents help to incubate it. When the egg hatches, both parents help feed the youngster, by regurgitating fish. The young fledges after about 2 months, but is still typically tended to by the parents for another month after that.

Song

The Bridled Tern gives a variety of sharp, rasping, and somewhat nasal calls, often described as harsh kreeek or grating chatter notes. Colonies can be noisy during the breeding season as birds use these calls for territorial defense, mate recognition, and communication among nesting neighbors.

Migration

In North America, small numbers have nested in southern Florida in recent decades, but are only present during the summer months. Most depart for warmer waters in the winter, but there have been some sightings of Bridled Terns in the winter, in warmer waters off the coast.

Interactive eBird Map

Click to access an interactive map of Bridled Tern sightings

Similar Species

Sooty Tern. The Sooty Tern is distinguished by its solid black back and a white forehead patch that stops just before the eye. In contrast, the Bridled Tern has a lighter, more charcoal-grey back and a more extensive white forehead patch that continues past the eye as a distinct eyebrow streak.

Conservation Status

Population trends are relatively stable, they are found over a wide geographic area, and they are relatively common in parts of their range. The IUCN lists the Bridled Tern as a species of "Least Concern" .

Further Information

Photo Information

Photo taken by Frankie Chu - Photo licensed under Creative Commons Attribution NoDerivs 2.0 Generic License.