man-o'-war bird or frigate-bird, most aerial of the water birds, found in the tropic seas. The man-o'-war bird's wingspread (7 1-2 ft/228.5 cm) is the largest in proportion to its body (3–4 lb/1.4–1.8 kg) of any bird. It can soar motionless by the hour and has been recorded in flights lasting nearly four days, spending most of that time several hundred feet or more in the air. It is awkward on land and in the sea, where the feathers quickly become water-logged.

The name derives from its grace and swiftness in the air and from its piratical tendencies; it harasses boobies, pelicans, cormorants, and gulls until they drop their catch. Man-o'-war birds feed chiefly on fish but also prey on the young of sea birds and on jellyfish, squid, and young turtles. They have long hooked beaks and forked tails; the male has an inflatable orange throat pouch that becomes red at courtship time.

The purplish black magnificent frigate-bird, Fregata magnificens, 40 in. (100 cm) long, is found from the Bahamas and Baja California S to Brazil and Ecuador; the great frigate-bird, F. minor, is found in the Indian Ocean. Other species, e.g., the Ascension and Christmas Island frigate-birds, are named for their habitats. The lesser frigate-bird, the smallest (32 in./80 cm) of the family, is found in the South Pacific and on the islands off Brazil and Madagascar.

Frigate-birds are classified in the phylum Chordata Chordata (kôrdā`tə,–dä`–)
..... Click the link for more information. , subphylum Vertebrata, class Aves, order Pelecaniformes, family Fregatidae.

frigate bird

or man-o'-war bird

Great frigate bird (Fregata minor)

(credit: Jen and Des Bartlett—Bruce Coleman Inc./EB Inc.)

Any member of five species of large seabirds constituting the family Fregatidae, found worldwide along tropical and semitropical coasts and islands. About the size of a hen, frigate birds have extremely long, slender wings, which span up to about 8 ft (2.3 m), and long, deeply forked tails. Most adult males are all black; most females are marked with white below. Both sexes have a bare-skinned throat pouch, tiny feet, and a long hooked bill that is used to attack and rob other seabirds of their fish. The courting male's throat pouch becomes bright red and is inflated to the size of a person's head. Perhaps the most aerial of all birds except the swifts, frigate birds land only to sleep or tend the nest.