Magnificent frigatebird

Frigatebirds live by warm seas.

They usually nest on small islands with lots of trees and bushes.

Magnificent frigatebirds live along the warm coasts of the Americas. On the Pacific side they are found from California to Ecuador, including the Galápagos Islands. On the Atlantic side they live from Florida through the Caribbean to southern Brazil.

They nest on islands, usually small ones covered in mangroves or other trees and bushes. Frigatebirds sometimes soar over land near the coast, and in Panama they cross from one ocean to the other.

The IUCN gives the range as the Pacific and Atlantic coasts of the Americas, from California to Ecuador (including the Galápagos) and from Florida to southern Brazil; a relict population that used to breed in Cabo Verde, off Africa, is now feared extinct (Orta et al. 2018). ADW (2006) puts breeding between about 25 degrees north (Mexico and Florida) and 27 degrees south (Brazil).

Audubon's account (Kaufman 1996) describes warm waters, usually along coasts but sometimes far offshore, and birds soaring inland across the Isthmus of Panama. The species is apparently not truly migratory: it is present year-round in southern Florida and more common in summer along the Gulf Coast, while nonbreeders and immatures turn up far from colonies in every season.

Frigatebirds eat fish and squid.

They grab food from the top of the water while they fly.

Frigatebirds eat mostly fish, especially flying fish, and squid. They also eat jellyfish, crustaceans (the group that includes crabs and shrimp), baby turtles, and the eggs and chicks of other seabirds.

A frigatebird never lands on the sea to fish. It swoops down and snatches food from the surface, hardly touching the water. It also chases other seabirds, such as boobies, gulls and terns, until they drop or bring up their food, and then catches it in midair.

The IUCN lists mainly flying fish and squid, with jellyfish, baby turtles, seabird eggs and chicks, offal and fish scraps (del Hoyo et al. 1992). The species relies on prey driven to the surface by underwater predators such as tuna; ADW notes frigatebirds are often found near groups of dolphins or tuna.

Audubon's account describes birds swooping to take food from on or near the surface with very little contact with the water, never swimming, and taking prey from beaches without landing. ADW says a dipping bird reaches only about 15 centimeters below the surface, to avoid wetting its feathers. Both describe piracy (kleptoparasitism): chasing other birds until they drop or disgorge their catch. ADW names gulls, gannets, terns and boobies as victims and says a frigatebird may grab a victim's tail feathers.

To find a partner, the male puffs up his red throat like a balloon.

Females fly above and choose one.

In the breeding season, males often perch together in groups and show off. Each male puffs up his throat pouch into a huge red balloon, points his bill up, shakes his half-open wings, sways back and forth and calls.

Females fly overhead and look at the group, then choose one male as a mate. Frigatebirds are usually silent at sea, but they make harsh, throaty calls during courtship.

Perched males display, often in groups, by inflating the throat pouch into a huge red balloon, raising the bill, vibrating the partly spread wings, swiveling and calling; females flying overhead are drawn to the group and choose a mate (Audubon guide, Kaufman 1996). ADW (2006) adds that an inflated sac can hide the male's head and that males make a drumming noise during the display.

Pairs are monogamous within a breeding season but rarely keep the same partner from one season to the next (ADW). Birds are usually silent at sea and give harsh guttural calls in courtship.

There are lots of magnificent frigatebirds.

They need islands to nest on and places on the coast to rest.

The magnificent frigatebird is listed as least concern, but its numbers are going down slowly. Scientists estimated about 130,000 adults in 2019. Hunting at nesting sites is a likely cause, and building on Caribbean coasts has reduced some colonies and their resting places.

A small group of frigatebirds once nested on Cabo Verde, islands off Africa, but they are now feared to be gone. In Florida, frigatebirds were first confirmed nesting in the late 1960s.

BirdLife International assessed Fregata magnificens as Least Concern for the IUCN Red List (assessed 20 February 2020, published 2020): an extremely large range and about 130,000 mature individuals (Partners in Flight 2019), with a decreasing trend that is not believed to be rapid enough to approach Vulnerable. Hunting likely occurs at numerous breeding sites, causing slow but significant declines; the Cabo Verde subpopulation has declined to the point of extinction following persecution by fishermen (Orta et al. 2018). Coastal development in the Caribbean has caused local declines and the loss of roosting sites, though no effect on the total population has been documented.

Audubon's account (Kaufman 1996) notes that the population is hard to monitor, that breeding in Florida was first confirmed in the late 1960s on the Marquesas Keys, and that nesting at the Dry Tortugas began in 1988.