Magnificent frigatebird

The magnificent frigatebird (Fregata magnificens), frigate petrel or man o' war is a seabird of the frigatebird family Fregatidae. With a length of 89–114 centimetres (2 ft 11 in – 3 ft 9 in) and wingspan of 2.17–2.44 m (7 ft 1 in – 8 ft 0 in), it is the largest species of frigatebird. It occurs over tropical and subtropical waters off America, between northern Mexico and Peru on the Pacific coast and between Florida and southern Brazil along the Atlantic coast. There are also populations on the Galápagos Islands in the Pacific and the Cape Verde islands in the Atlantic. It is one of the fastest birds in the world, flying at speeds of up to 153 kilometres (95 mi) per hour.

The magnificent frigatebird is a large, lightly built seabird with brownish-black plumage, long narrow wings and a deeply forked tail. The male has a striking red gular sac which he inflates to attract a mate. The female is slightly larger than the male and has a white breast and belly. Frigatebirds feed on fish taken in flight from the ocean's surface (often flying fish), and sometimes indulge in kleptoparasitism, harassing other birds to force them to regurgitate their food.

The magnificent frigatebird was originally considered to belong to the species Fregata aquila but in 1914 the Australian ornithologist Gregory Mathews proposed that the magnificent frigatebird should be considered as a separate species with the binomial name Fregata magnificens. Of the four other species within the genus Fregata, genetic analysis has shown that the magnificent frigatebird is most closely related to the Ascension frigatebird (Fregata aquila).

There are two subspecies:

Prior to 2022, both these subspecies were considered synonymous with one another and grouped under F. m. magnificens. However, they were split by the International Ornithological Congress in 2022 based on a 2011 study which examined genetic and morphological variation in magnificent frigatebirds, finding both expected and also highly unexpected results. As predicted by the flight capacity of the species, the authors found signatures of high gene flow across most of the distribution range. This included evidence of recent gene flow among Pacific and Atlantic localities, likely across the Isthmus of Panama. This geological formation is a strong barrier to movement in most tropical seabirds. However, the same study also found that the magnificent frigatebird on the Galápagos Islands is genetically and morphologically distinct. Based on this study, the Galápagos population has not been exchanging any genes with their mainland counterparts for several hundred thousand years.

Christopher Columbus encountered magnificent frigatebirds when passing the Cape Verde Islands on his first voyage across the Atlantic in 1492. His journal for the voyage survives in a version made in the 1530s by Bartolomé de las Casas. The entry for 29 September reads in English:

They saw a bird that is called a frigatebird, which makes the boobies throw up what they eat in order to eat it herself, and she does not sustain herself on anything else. It is a seabird, but does not alight on the sea nor depart from land 20 leagues [97 km; 60 mi]. There are many of these on the islands of Cape Verde.

In the 15th century text the name of the bird is written as rabiforçado. The modern Spanish word for a frigatebird is rabihorcado or "forked tail". A population of magnificent frigatebirds once bred on the Cape Verde Islands but is now probably extinct.