Bridled Tern

The Bridled Tern is a graceful, wide-ranging seabird of tropical and subtropical oceans, closely related to and often confused with the Sooty Tern. It gets its name from the thin white line that runs from the forehead patch back through the eye like a bridle strap.

Appearance

Adults are dark grey-brown above (paler and browner than the blackish Sooty Tern) with white underparts, a white forehead patch extending behind the eye as a narrow line, and a pale grey-white collar across the hindneck that further separates it from the Sooty Tern.

Key field marks

• Grey-brown (not blackish) upperparts
• White forehead patch extending behind the eye as a thin line, the source of its name
• Pale collar around the hindneck
• Deeply forked tail with white outer edges
• Buoyant, graceful flight, often lower over the water than the Sooty Tern

Similar species

The Bridled Tern is most similar to the Sooty Tern but is paler and browner overall, with the eye-line extension and hindneck collar being the clearest distinguishing features at close range.

Habitat and range

Bridled Terns breed on rocky islands, cliffs, and coral cays across tropical and subtropical waters of the Atlantic, Indian, and Pacific Oceans. Outside the breeding season they are highly pelagic, ranging widely over open ocean and rarely approaching shore except near their colonies.

Some populations are resident near breeding islands year-round, while others disperse over long distances across ocean basins between breeding attempts.

Behavior

Bridled Terns feed by picking small fish, squid, and crustaceans from the ocean surface in flight, often associating loosely with drifting debris or schools of predatory fish that push prey upward. They fly with a light, buoyant, somewhat languid style compared to the more powerful Sooty Tern.

Voice

Calls include a low, barking "wep" or growling note, quieter and less far-carrying than the Sooty Tern's cry.

Nesting and breeding

Pairs nest in scattered, less densely packed colonies than Sooty Terns, often tucking a single egg into a rock crevice, under vegetation, or in a sheltered scrape on cliffs and rocky islets.