Did You Know We Have Frigate Birds in Trinidad Too?

Did you know we have Frigate Birds in Trinidad too? If you have ever looked up along the coast and spotted a large black bird with long, angular wings and a deeply forked tail hanging almost motionless in the sky, chances are you were watching a frigatebird.

The one you are most likely to see here is the Magnificent Frigatebird (Fregata magnificens), a bird of Caribbean and Atlantic coasts that patrols the waters around Trinidad and Tobago through much of the year. The much rarer Lesser Frigatebird turns up only occasionally as a visitor, which is part of what made the rescue of Tex, a Lesser Frigate Bird, such an unusual event for our team.

Telling them apart is easier than you might think. Males are entirely black with a glossy sheen, females are larger and show a white breast, and young birds have pale, whitish heads. In frigatebirds the female actually outsizes the male, a reversal of the pattern seen in most birds. With a wingspan that can stretch beyond two metres set against a very light body, they carry one of the largest wing areas relative to weight of any bird alive.

That build makes them supreme gliders. Riding thermals and sea breezes, a frigatebird can stay aloft for days at a time and come down only to roost on trees or remote cliffs at night. Their main prey are fish and squid, snatched from the surface in flight or seized as larger predators such as tuna drive them upward.

Unlike most seabirds, frigatebirds cannot settle on the water. Their feathers are not fully waterproof and their small legs and feet cannot launch them off the surface, so a bird that becomes waterlogged is in serious trouble. To make up the difference they are accomplished pirates: the term kleptoparasite describes their habit of harassing other seabirds in mid-air until a meal is dropped, and they will even take unguarded chicks from the nest.

The most striking sight of all belongs to the breeding male. During courtship he inflates a brilliant scarlet throat pouch, the gular sac, into a great red balloon and drums on it while calling to passing females, a display that can take many minutes to fully swell.

Frigatebirds are seasonally monogamous and nest in colonies, building a rough platform of sticks in low trees or on the ground of remote islands. A single egg is laid each season, and the young are cared for longer than almost any other bird, so long that most pairs can only breed every other year. That slow pace of reproduction is exactly why healthy coastlines and undisturbed roosting sites matter so much, and why every rescued bird counts.