Ascension Frigatebird
Encyclopedia
The Ascension Frigatebird (Fregata aquila) breeds only on the tiny Boatswain Bird Island
just off Ascension Island
in the tropical Atlantic Ocean
. It formerly bred on the larger island, but was exterminated by introduced cat
s, Brown Rat
s, and human persecution.
It breeds on the rocky slopes of Boatswainbird. As with other frigatebird
s its movements when not breeding are little known because of identification problems within this difficult group, but it occurs off west Africa
.
A frigatebird found moribund in 1953 in Tiree
, Scotland
was identified at the time as Magnificent Frigatebird
but was re-examined in 2002 and found to be an Ascension Frigatebird.
It feeds on fish
and similar surface prey such as small turtle
s.
This species is very similar to the other frigatebirds and is similarly sized to all but Lesser Frigatebird
. It has a white axillary spur, and juveniles show a white head, and a distinctly white hind neck with no reddish-brown hue. It has a brown breast band.
Boatswain Bird Island
Boatswain Bird Island is an island some 270 metres off the east coast of Ascension Island in the South Atlantic Ocean with an area of approximately 5.3 hectares...
just off Ascension Island
Ascension Island
Ascension Island is an isolated volcanic island in the equatorial waters of the South Atlantic Ocean, around from the coast of Africa and from the coast of South America, which is roughly midway between the horn of South America and Africa...
in the tropical Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
. It formerly bred on the larger island, but was exterminated by introduced cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s, Brown Rat
Brown Rat
The brown rat, common rat, sewer rat, Hanover rat, Norway rat, Brown Norway rat, Norwegian rat, or wharf rat is one of the best known and most common rats....
s, and human persecution.
It breeds on the rocky slopes of Boatswainbird. As with other frigatebird
Frigatebird
The frigatebirds are a family, Fregatidae, of seabirds. There are five species in the single genus Fregata. They are also sometimes called Man of War birds or Pirate birds. Since they are related to the pelicans, the term "frigate pelican" is also a name applied to them...
s its movements when not breeding are little known because of identification problems within this difficult group, but it occurs off west Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
.
A frigatebird found moribund in 1953 in Tiree
Tiree
-History:Tiree is known for the 1st century BC Dùn Mòr broch, for the prehistoric carved Ringing Stone and for the birds of the Ceann a' Mhara headland....
, Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
was identified at the time as Magnificent Frigatebird
Magnificent Frigatebird
The Magnificent Frigatebird was sometimes previously known as Man O'War, reflecting its rakish lines, speed, and aerial piracy of other birds....
but was re-examined in 2002 and found to be an Ascension Frigatebird.
It feeds on fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
and similar surface prey such as small turtle
Turtle
Turtles are reptiles of the order Testudines , characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield...
s.
This species is very similar to the other frigatebirds and is similarly sized to all but Lesser Frigatebird
Lesser Frigatebird
The Lesser Frigatebird, Fregata ariel, is a species of frigatebird.It nests in Australia, among other locations.There is a single record from the Western Palearctic, from Eilat in the Gulf of Aqaba....
. It has a white axillary spur, and juveniles show a white head, and a distinctly white hind neck with no reddish-brown hue. It has a brown breast band.