Henderson Petrel
Encyclopedia
The Henderson Petrel is a ground-nesting species of seabird
in the Procellariidae
family. Adult species measure on average 37 cm. It has a uniform grey-brown plumage. It is classified among the Gadfly petrel
s.
It is found in the Pitcairn Islands
, and possibly in French Polynesia
, though confusion over the taxon
makes reports of this species in the Marquesas, Tuamotus
, Australs
and Gambiers
uncertain. Breeding colonies formerly existed on Ducie
, but were wiped out by invasive rats by 1922. It now is believed to nest uniquely on the Henderson island
atoll
, which was declaired a World Heritage Site
in 1988. The International Union for Conservation of Nature classifies it as closely related to Pterodroma arminjoniana and Pterodroma heraldica. Its natural habitat is the moist subtropical scrub found on that island. The endangered habitat of this species was identified in 2007 as requiring urgent action to restore it.
During Captain Cook's first voyage
, Daniel Solander
recorded in his manuscript on the 21 March 1769 his observations on a new petrel, on which he named Procellaria atrata. Solander's account only became known when Gregory Mathews
published Solander's account in 1912. Mathews renamed it Pterodroma atrata, since dark-plumage birds of this species were considered to be dark-morph Herald petrels. It was only as late as 1996 that evidence was provided that these birds were specifically distinct from pale-morph Herald Petrels.
Millions of pairs of Henderson petrel used to breed on the island several centuries ago. Brooke calculated breeding pairs to be around 16,000 in 1991/2. Contemporary colony numbers are estimated to be in the 40,000 range. The Pacific rat
(rattus exulans), introduced by local Polynesian traders, has almost wiped out the existing colony, devouring 25,000 petrel chicks per annum. To save the species from imminent extinction, the Royal Society for the Protection of Birds
, in a last-ditch £1.5 million project, has mounted an attempt to achieve a massive rodent cull to exterminate the predator population on the island. This attempt to re-establish a rat-free habitat will take place in August, 2011.
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...
in the Procellariidae
Procellariidae
The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes , which also includes the albatrosses, the storm-petrels, and the diving petrels.The procellariids are...
family. Adult species measure on average 37 cm. It has a uniform grey-brown plumage. It is classified among the Gadfly petrel
Gadfly petrel
The gadfly petrels are seabirds in the bird order Procellariiformes. These medium to large petrels feed on food items picked from the ocean surface....
s.
It is found in the Pitcairn Islands
Pitcairn Islands
The Pitcairn Islands , officially named the Pitcairn, Henderson, Ducie and Oeno Islands, form a group of four volcanic islands in the southern Pacific Ocean. The islands are a British Overseas Territory and overseas territory of the European Union in the Pacific...
, and possibly in French Polynesia
French Polynesia
French Polynesia is an overseas country of the French Republic . It is made up of several groups of Polynesian islands, the most famous island being Tahiti in the Society Islands group, which is also the most populous island and the seat of the capital of the territory...
, though confusion over the taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
makes reports of this species in the Marquesas, Tuamotus
Tuamotus
The Tuamotus or the Tuamotu Archipelago are a chain of islands and atolls in French Polynesia. They form the largest chain of atolls in the world, spanning an area of the Pacific Ocean roughly the size of Western Europe...
, Australs
Austral Islands
The Austral Islands are the southernmost group of islands in French Polynesia, an overseas collectivity of France in the South Pacific. Geographically, they consist of two separate archipelagos, namely in the northwest the Tubuai Islands consisting of the Îles Maria, Rimatara, Rurutu, Tubuai...
and Gambiers
Gambier Islands
There was a time when the Gambiers hosted a population of several thousand people and traded with other island groups including the Marquesas, the Society Islands and Pitcairn Islands...
uncertain. Breeding colonies formerly existed on Ducie
Ducie Island
Ducie Island is an uninhabited atoll in the Pitcairn Islands. It lies east of Pitcairn and has a total area of , which includes the lagoon. It is long, measured northeast to southwest, and about wide. The island is composed of four islets: Acadia, Pandora, Westward and Edwards.Despite its...
, but were wiped out by invasive rats by 1922. It now is believed to nest uniquely on the Henderson island
Henderson Island (Pitcairn Islands)
Henderson Island is an uninhabited raised coral atoll in the south Pacific Ocean, that in 1902 was annexed to the Pitcairn Islands colony, a South Pacific Dependent Territory of the United Kingdom. Measuring long and wide, it has an area of and is located northeast of Pitcairn Island at . The...
atoll
Atoll
An atoll is a coral island that encircles a lagoon partially or completely.- Usage :The word atoll comes from the Dhivehi word atholhu OED...
, which was declaired a World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
in 1988. The International Union for Conservation of Nature classifies it as closely related to Pterodroma arminjoniana and Pterodroma heraldica. Its natural habitat is the moist subtropical scrub found on that island. The endangered habitat of this species was identified in 2007 as requiring urgent action to restore it.
During Captain Cook's first voyage
First voyage of James Cook
The first voyage of James Cook was a combined Royal Navy and Royal Society expedition to the south Pacific ocean aboard HMS Endeavour, from 1768 to 1771...
, Daniel Solander
Daniel Solander
Daniel Carlsson Solander or Daniel Charles Solander was a Swedish naturalist and an apostle of Carl Linnaeus. Solander was the first university educated scientist to set foot on Australian soil.-Biography:...
recorded in his manuscript on the 21 March 1769 his observations on a new petrel, on which he named Procellaria atrata. Solander's account only became known when Gregory Mathews
Gregory Mathews
Gregory Macalister Mathews CBE was an Australian amateur ornithologist.Mathews made his fortune in mining shares, and moved to England around 1900....
published Solander's account in 1912. Mathews renamed it Pterodroma atrata, since dark-plumage birds of this species were considered to be dark-morph Herald petrels. It was only as late as 1996 that evidence was provided that these birds were specifically distinct from pale-morph Herald Petrels.
Millions of pairs of Henderson petrel used to breed on the island several centuries ago. Brooke calculated breeding pairs to be around 16,000 in 1991/2. Contemporary colony numbers are estimated to be in the 40,000 range. The Pacific rat
Polynesian Rat
The Polynesian Rat, or Pacific Rat , known to the Māori as kiore, is the third most widespread species of rat in the world behind the Brown Rat and Black Rat. The Polynesian Rat originates in Southeast Asia but, like its cousins, has become well travelled – infiltrating Fiji and most Polynesian...
(rattus exulans), introduced by local Polynesian traders, has almost wiped out the existing colony, devouring 25,000 petrel chicks per annum. To save the species from imminent extinction, the Royal Society for the Protection of Birds
Royal Society for the Protection of Birds
Bird Notes and News was first published in April 1903.The title changed to 'Bird Notes' in 1947. In the 1950s, there were four copies per year . Each volume covered two years, spread over three calendar years...
, in a last-ditch £1.5 million project, has mounted an attempt to achieve a massive rodent cull to exterminate the predator population on the island. This attempt to re-establish a rat-free habitat will take place in August, 2011.