Auckland Rail
Encyclopedia
The Auckland Rail is a small nearly flightless rail
endemic to the Auckland Islands
460 km south of New Zealand
. It is somewhat of a biogeographical
anomaly, being the only species in the genus Lewinia
to have reached the islands of New Zealand, skipping over the main islands to reach the remote Auckland group. Its closest relative being the Lewin's Rail
of Australia
. The species is currently restricted to two islands in the Auckland group, Adams Island
and Disappointment Island
.
The Auckland Rail is a small rail with chestnut back plumage
and a grey breast. The flanks are barred black and white and the head is red-brown, with a red bill
. It is smaller than the Australian Lewins' Rail. There are conflicting reports about its ability to fly, early accounts suggested it could, but recent researchers have found little evidence for this. If the species is able to fly it does so very infrequently. Auckland Rails have a variety of calls
, the most common being a crex call made at one second intervals 10 or more times in a row. The function of the calls is unknown.
Little is known about the breeding biology of the Auckland Rail. The few nests that have been found contained clutches of two eggs, probably laid in early November. The eggs are cream coloured with red, brown and grey spots.
The Auckland Rail is highly secretive and was considered to be extinct for many years before its rediscovery. The population is currently stable on the two islands it survives on. It is thought to have become extinct on the main Auckland Islands
due to the presence of introduced feral cat
s and pig
s; it is hoped the eventual removal of these from the islands will allow for reintroductions to other islands in the group. The species is currently considered vulnerable
by the IUCN and BirdLife International
due to the possibility of rats or other predators reaching the two islands it survives on.
Rallidae
The rails, or Rallidae, are a large cosmopolitan family of small to medium-sized birds. The family exhibits considerable diversity and the family also includes the crakes, coots, and gallinules...
endemic to the Auckland Islands
Auckland Islands
The Auckland Islands are an archipelago of the New Zealand Sub-Antarctic Islands and include Auckland Island, Adams Island, Enderby Island, Disappointment Island, Ewing Island, Rose Island, Dundas Island and Green Island, with a combined area of...
460 km south of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. It is somewhat of a biogeographical
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
anomaly, being the only species in the genus Lewinia
Lewinia
Lewinia is a genus of bird in the Rallidae family. It contains the following species:* Lewin's Rail, Lewinia pectoralis* Brown-banded Rail, Lewinia mirifica* Auckland Rail, Lewinia muelleri...
to have reached the islands of New Zealand, skipping over the main islands to reach the remote Auckland group. Its closest relative being the Lewin's Rail
Lewin's Rail
The Lewin's Rail is a species of bird in the Rallidae family.It is found in Australia, Indonesia, and Papua New Guinea.Its natural habitat is subtropical or tropical moist lowland forests....
of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. The species is currently restricted to two islands in the Auckland group, Adams Island
Adams Island, New Zealand
Adams Island is part of Auckland Islands archipelago. The southern end of Auckland Island broadens to a width of where a narrow channel, known as Carnley Harbour or the Adams Straits, separates it from the roughly triangular Adams Island , which is even more mountainous, reaching a height of at...
and Disappointment Island
Disappointment Island
Disappointment Island is one of seven uninhabited islands of the archipelago Auckland Islands. It is from the north-west end of Auckland Island and south of New Zealand. It is home to the White-capped Albatross. About 65,000 pairs - nearly the entire world population - nest on Disappointment...
.
The Auckland Rail is a small rail with chestnut back plumage
Plumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
and a grey breast. The flanks are barred black and white and the head is red-brown, with a red bill
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
. It is smaller than the Australian Lewins' Rail. There are conflicting reports about its ability to fly, early accounts suggested it could, but recent researchers have found little evidence for this. If the species is able to fly it does so very infrequently. Auckland Rails have a variety of calls
Bird song
Bird vocalization includes both bird calls and bird songs. In non-technical use, bird songs are the bird sounds that are melodious to the human ear. In ornithology and birding, songs are distinguished by function from calls.-Definition:The distinction between songs and calls is based upon...
, the most common being a crex call made at one second intervals 10 or more times in a row. The function of the calls is unknown.
Little is known about the breeding biology of the Auckland Rail. The few nests that have been found contained clutches of two eggs, probably laid in early November. The eggs are cream coloured with red, brown and grey spots.
The Auckland Rail is highly secretive and was considered to be extinct for many years before its rediscovery. The population is currently stable on the two islands it survives on. It is thought to have become extinct on the main Auckland Islands
Auckland Islands
The Auckland Islands are an archipelago of the New Zealand Sub-Antarctic Islands and include Auckland Island, Adams Island, Enderby Island, Disappointment Island, Ewing Island, Rose Island, Dundas Island and Green Island, with a combined area of...
due to the presence of introduced feral cat
Feral cat
A feral cat is a descendant of a domesticated cat that has returned to the wild. It is distinguished from a stray cat, which is a pet cat that has been lost or abandoned, while feral cats are born in the wild; the offspring of a stray cat can be considered feral if born in the wild.In many parts of...
s and pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
s; it is hoped the eventual removal of these from the islands will allow for reintroductions to other islands in the group. The species is currently considered vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
by the IUCN and BirdLife International
BirdLife International
BirdLife International is a global Partnership of conservation organisations that strives to conserve birds, their habitats and global biodiversity, working with people towards sustainability in the use of natural resources...
due to the possibility of rats or other predators reaching the two islands it survives on.