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Conservation concerns Scientists classify Fregata aquila as a vulnerable species because it breeds only on one tiny island and there is a major concern of invasion by many feral cats. The issue of censuring the species’ population has proved problematic and for this reason, population trends are difficult to ascertain. Fishing activities have greatly contributed to the growing vulnerability concerns. The Fregata aquila is a large seabird which is known for its long wings and a forked tail that is surprisingly long. Adult males are black and have a green gloss on the forehead they have long feathers and the gular region is bright red. The gular region can become inflated to assume the shape and size of a rugby ball. Adult males are often inseparable from Magnificent frigatebirds. The female of this species is the only member of the frigatebird family whose younger members lack any white pigmentation on the head and chest. Geographical Range population Boatswainbird Islet is the name of the island which forms the only breeding ground for Fregata aquila in the world. This islet is 250 m to the north of Ascension Island. No wonder this bird is referred to as Ascension frigatebird. This island is in the Atlantic Ocean. Serious declines in the bird’s population have been recorded in recent times. In 1997, there were only between 5000 and 10000 Ascension frigatebirds remaining. Currently, only 10,113 female birds of this species remain. In total, there are less than 20,000 Fregata aquila existing today. This data is not very accurate since it is difficult to carry out census work. Fregata aquila normally spend a lot of time away from this island. They sometimes fly as far as off the West African coast. They normally end up in the Congo mouth or the Gulf of Guinea. Ecology The Fregata aquila is a typical surface feeder. Its main source of food is fish. The bird likes Flying fish and green turtles especially those that have been recently hatched. Breeding is mainly in the form of for colonies which are rather loosely knit. Breeding mainly takes place in summit plateau. The rougher areas are the most appropriate for these birds. Majority of these birds are to be found on the ledges of plateaus when time for breeding approaches. Breeding is thought to take place all year round, that is, it can happen at any time of the year. This is a peculiar phenomenon. However, some scientists have presented evidence of seasonality of breeding patterns. They say that laying increases between early May and late October. They also say there is a sharp decline in number of eggs laid between February and April. The breeding success of Fregata aquila is very low and they have a clutch size of one. Threats Predation by human beings is the main cause of severe declines in recent years. Feral and black rats are also a real threat to the Fregata aquila especially at their breeding ground. Since the Japanese introduced, in1988, longline fishery in areas that are adjacent to the Ascension Island, mortality rate of Fregata aquila has gone up.
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