Polynesian Megapode
Encyclopedia
The Tongan Megapode is a species of bird
in the megapode family Megapodiidae, currently endemic to Tonga
. The species is also known as the Polynesian Megapode, and as the Niuafo'ou Megapode after the island of Niuafo'ou
to which it was restricted for many years. The Tongan Megapode is the only remaining species of megapode in Tonga out of the four or five species that were present on the islands in prehuman times (as shown through the fossil
record), and indeed the only species of megapode that survives in Polynesia
. Similar extinctions occurred in Fiji
and New Caledonia
, which apparently had three species in prehistory. The species itself once had a more widespread distribution, occurring across most of Tonga, Samoa
and Niue
. The cause of all these extinctions and declines was the arrival of humans on the islands, and the associated predation on adults and particularly eggs, as well as predation by introduced species
. On Niuafo'ou the small human population and remoteness of its habitat probably saved the species.
Its natural habitat
is tropical moist lowland forest
s. On Niuafo'ou it is most common on the central caldera. The Tongan Megapode, like all megapodes, does not incubate
its eggs by sitting on them; instead the species buries them in warm volcanic sands and soil and allows them to develop. On islands in former parts of its range without volcanoes it presumably created mounds of rotting vegetation and laid the eggs there. The young birds are capable of flying immediately after hatching.
Today the Tongan Megapode is principally threatened by the same factors that caused its decline in the rest of Polynesia. Its eggs are still harvested by local people in spite of theoretical government protection, and some hunting still occurs. The species is apparently afforded some protection by the difficulty in reaching its habitat. Because of the vulnerability of the single population an attempt was made to translocate
eggs of this species to new islands, Late
and Fonualei
. The translocation was successful on Fonualei and an estimated 350–500 birds now breed there, but surveys of Late subsequently found that the translocation there had failed.
The binomial of this bird commemorates British consul William Thomas Pritchard
.
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
in the megapode family Megapodiidae, currently endemic to Tonga
Tonga
Tonga, officially the Kingdom of Tonga , is a state and an archipelago in the South Pacific Ocean, comprising 176 islands scattered over of ocean in the South Pacific...
. The species is also known as the Polynesian Megapode, and as the Niuafo'ou Megapode after the island of Niuafo'ou
Niuafo'ou
Niuafoou is the most northerly island in the kingdom of Tonga. It is a volcanic rim island of 15 km² and with a population of 650 in 2006.-Geography:...
to which it was restricted for many years. The Tongan Megapode is the only remaining species of megapode in Tonga out of the four or five species that were present on the islands in prehuman times (as shown through the fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
record), and indeed the only species of megapode that survives in Polynesia
Polynesia
Polynesia is a subregion of Oceania, made up of over 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are termed Polynesians and they share many similar traits including language, culture and beliefs...
. Similar extinctions occurred in Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
and New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
, which apparently had three species in prehistory. The species itself once had a more widespread distribution, occurring across most of Tonga, Samoa
Samoa
Samoa , officially the Independent State of Samoa, formerly known as Western Samoa is a country encompassing the western part of the Samoan Islands in the South Pacific Ocean. It became independent from New Zealand in 1962. The two main islands of Samoa are Upolu and one of the biggest islands in...
and Niue
Niue
Niue , is an island country in the South Pacific Ocean. It is commonly known as the "Rock of Polynesia", and inhabitants of the island call it "the Rock" for short. Niue is northeast of New Zealand in a triangle between Tonga to the southwest, the Samoas to the northwest, and the Cook Islands to...
. The cause of all these extinctions and declines was the arrival of humans on the islands, and the associated predation on adults and particularly eggs, as well as predation by introduced species
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
. On Niuafo'ou the small human population and remoteness of its habitat probably saved the species.
Its natural habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
is tropical moist lowland forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s. On Niuafo'ou it is most common on the central caldera. The Tongan Megapode, like all megapodes, does not incubate
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
its eggs by sitting on them; instead the species buries them in warm volcanic sands and soil and allows them to develop. On islands in former parts of its range without volcanoes it presumably created mounds of rotting vegetation and laid the eggs there. The young birds are capable of flying immediately after hatching.
Today the Tongan Megapode is principally threatened by the same factors that caused its decline in the rest of Polynesia. Its eggs are still harvested by local people in spite of theoretical government protection, and some hunting still occurs. The species is apparently afforded some protection by the difficulty in reaching its habitat. Because of the vulnerability of the single population an attempt was made to translocate
Translocation (Wildlife conservation)
Translocation in wildlife conservation means capture, transport and release or introduction of species, habitats or other ecological material from one location to another...
eggs of this species to new islands, Late
Late (Tonga)
Late Island is an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga.The small, 6-km-wide circular island of Late, lying along the Tofua volcanic arc about 55 km WSW of the island of Vavau, contains a 400-m-wide, 150-m-deep summit crater with an ephemeral lake...
and Fonualei
Fonualei (volcano)
Fonualei is a volcanic island close to Vavau in the kingdom of Tonga.It was seen by Don Francisco Antonio Mourelle on the La Princesa in February 1781. He reported the island to be barren from eruptions, and called it for that reason Bitterness island....
. The translocation was successful on Fonualei and an estimated 350–500 birds now breed there, but surveys of Late subsequently found that the translocation there had failed.
The binomial of this bird commemorates British consul William Thomas Pritchard
William Thomas Pritchard
William Thomas Pritchard was a British consul and adventurer.Pritchard was born in Papeete, Tahiti, the son of George Pritchard. He was educated in Britain before returning to join his father, the British consul in Samoa. In Samoa, he acquired an exceptional knowledge of the Polynesian language...
.