A large, long-winged tropical seabird with a remarkable red throat pouch that males inflate like a balloon during courtship, and a well-earned reputation as an aerial pirate that terrorizes other seabirds into dropping their food.
The red balloon
During the breeding season, male magnificent frigatebirds gather in colonies in low bushes and trees and inflate their bright scarlet gular pouches — thin-skinned throat sacs — into enormous bright-red balloons the size of a large football. They hold the position, shaking the pouch and rattling their bills, as females fly overhead inspecting potential mates.
Darwin observed this display in the Galapagos and wrote of it with evident surprise. The pouch serves no function outside of breeding display; it deflates completely for the rest of the year.
Aerial piracy
Frigatebirds have a diet supplement strategy called kleptoparasitism — pirating food from other birds. A frigatebird will chase a booby, tern, or pelican that has just caught a fish, harassing it with aerial maneuvers until the victim drops or regurgitates its catch, which the frigatebird then catches in mid-air before it hits the water.
This gives frigatebirds an infamous reputation, but piracy accounts for only a portion of their diet — they also catch fish, flying fish, squid, and seabird chicks directly.
Can’t get wet
Despite living at sea, frigatebirds have poorly waterproofed feathers compared to other seabirds. They cannot land on water and must catch everything in the air or from the surface without getting their plumage wet. This constraint shapes their hunting style — they are aerial specialists, not swimmers.
The largest wing area of any bird
Frigatebirds have the largest wing area relative to body weight of any bird — a ratio that produces exceptional soaring efficiency. They can remain aloft for weeks at a time with minimal energy expenditure, riding thermals and ocean wind systems across vast areas of open ocean.