Magnificent Frigatebird

The Magnificent Frigatebird is an aerial master of the tropical Americas, with an extraordinarily long, angular wingspan relative to its light body weight, allowing it to soar for hours with barely a wingbeat. Plumage is glossy black overall, with males showing an iridescent green-purple sheen and an extraordinary bright red throat pouch that can be inflated into a huge balloon-like display during courtship. Females are larger than males and show a white breast patch, while juveniles have white heads and underparts.

With its long, hooked bill, deeply forked tail, and silhouette often compared to a pterodactyl, the Magnificent Frigatebird is one of the most dramatic and easily recognized seabirds of the New World tropics.

Key field marks

• Long, narrow, angular wings and deeply forked tail
• All-black plumage in adult males, with iridescent sheen
• Bright red inflatable throat pouch in breeding males
• Females show a white breast patch; juveniles have white heads

Similar species

• Great Frigatebird and Lesser Frigatebird are very similar in shape but occur mainly in the Indo-Pacific; female Great Frigatebirds have a pale throat and reddish eye-ring, and Lesser Frigatebirds show white patches on the flanks ("spurs").
• No other New World seabird combines the deeply forked tail with such long, angular wings, making silhouette alone often diagnostic in the Americas.

Magnificent Frigatebirds breed colonially on remote islands and mangrove cays along tropical and subtropical coasts from the southeastern United States and the Gulf of Mexico south through the Caribbean and Central America to Peru and Brazil. They rarely land on water, instead roosting and nesting in trees, shrubs, or mangroves on predator-free islands.

The species ranges widely over coastal and offshore waters while foraging, and non-breeding birds and juveniles can wander far from colonies, occasionally appearing well outside the normal breeding range after storms.

Behavior

Frigatebirds are famous kleptoparasites, harassing other seabirds such as boobies and terns in flight until they drop or regurgitate their catch, which the frigatebird then snatches in midair; they also snatch flying fish and squid directly from the surface without landing on water, as their plumage is not waterproof.

Voice

Males produce a distinctive drumming, rattling sound with their bill against the inflated throat pouch during courtship displays, along with wavering whistles and clattering bill sounds.

Feeding

Flying fish, squid, and stolen food make up the diet, along with occasional seabird eggs and chicks taken opportunistically from unguarded nests.

Nesting and breeding

Males gather in groups and inflate their red gular pouches while calling to attract females; pairs build a stick nest in low trees or shrubs, and the single chick has one of the longest dependency periods of any bird, sometimes remaining reliant on parents for over a year.