Black Stilt
Encyclopedia
The Black Stilt or Kakī (Māori
), Himantopus novaezelandiae, is a large wader
in the avocet
and stilt
family Recurvirostridae
. The species is endemic to New Zealand
. Adults are 40 cm long. They have very long red legs, a long thin black bill and black plumage. Juveniles have a white breast, neck and head, with a black patch around the eyes.
in the world. Intensive management of kaki began in 1981, when the population had declined to just 23 adult birds. The current wild population is estimated at 85 adult birds (February 2010). There is a captive population of some 13 adults. Annual release in the wild of captive-bred birds, and predator control have probably prevented kaki from becoming extinct in the wild.
During the breeding season, it is restricted to the Mackenzie basin
in the South Island
. The majority of kaki will also overwinter in the Mackenzie basin, unlike other waders in the region that migrate to warmer climates for winter.
They breed at 2-3 years of age. They are one of the world's most endangered birds. Drainage and hydroelectric development has in the past disturbed their braided river bed habitat. Predation
from mammalian invasive species
, most notably mustelids such as stoats, presently poses a serious threat to the survival of the species. The third major threat to this species is hybridization with the local and more numerous Pied Stilt H. himantopus.
s beds of the South Island, it is threatened by changes in river flows as a result of new hydro dams and changes in flow regimes for existing dams.
The Upper Waitaki Power Development posed a threat to the habitat of the black silt. A programme was set up to lessen this threat. The Black Stilt population on the river beds varies with the river level. Changes in the level of Lake Benmore
, which caused corresponding changes in the deltas of the incoming rivers, affected the local population of Black Stilts.
Maori language
Māori or te reo Māori , commonly te reo , is the language of the indigenous population of New Zealand, the Māori. It has the status of an official language in New Zealand...
), Himantopus novaezelandiae, is a large wader
Wader
Waders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...
in the avocet
Avocet
The four species of Avocets are a genus, Recurvirostra, of waders in the same avian family as the stilts.Avocets have long legs and long, thin, upcurved bills which they sweep from side to side when feeding in the brackish or saline wetlands they prefer...
and stilt
Stilt
Stilt is a common name for several species of birds in the family Recurvirostridae, which also includes those known as avocets. They are found in brackish or saline wetlands in warm or hot climates....
family Recurvirostridae
Recurvirostridae
Recurvirostridae is a family of birds in the wader suborder Charadrii. It contains two distinct groups of birds, the avocets and the stilts .-Description and diet:...
. The species is endemic to 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...
. Adults are 40 cm long. They have very long red legs, a long thin black bill and black plumage. Juveniles have a white breast, neck and head, with a black patch around the eyes.
Ecology and conservation
Despite 20 years of intensive protection, this species remains the rarest wading birdWader
Waders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...
in the world. Intensive management of kaki began in 1981, when the population had declined to just 23 adult birds. The current wild population is estimated at 85 adult birds (February 2010). There is a captive population of some 13 adults. Annual release in the wild of captive-bred birds, and predator control have probably prevented kaki from becoming extinct in the wild.
During the breeding season, it is restricted to the Mackenzie basin
Mackenzie Basin
The Mackenzie Basin , is an elliptical intermontane basin, located in the Mackenzie and Waitaki Districts, near the centre of the South Island of New Zealand. It is the largest such basin in New Zealand...
in the South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...
. The majority of kaki will also overwinter in the Mackenzie basin, unlike other waders in the region that migrate to warmer climates for winter.
They breed at 2-3 years of age. They are one of the world's most endangered birds. Drainage and hydroelectric development has in the past disturbed their braided river bed habitat. Predation
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
from mammalian invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
, most notably mustelids such as stoats, presently poses a serious threat to the survival of the species. The third major threat to this species is hybridization with the local and more numerous Pied Stilt H. himantopus.
Effect of hydroelectric power development
Since the Black Stilt nests on the braided riverBraided river
A braided river is one of a number of channel types and has a channel that consists of a network of small channels separated by small and often temporary islands called braid bars or, in British usage, aits or eyots. Braided streams occur in rivers with high slope and/or large sediment load...
s beds of the South Island, it is threatened by changes in river flows as a result of new hydro dams and changes in flow regimes for existing dams.
The Upper Waitaki Power Development posed a threat to the habitat of the black silt. A programme was set up to lessen this threat. The Black Stilt population on the river beds varies with the river level. Changes in the level of Lake Benmore
Lake Benmore
Lake Benmore is a lake located in the South Island of New Zealand. It was artificially created in the 1960s by construction of Benmore Dam. The lake covers an area of approximately 75 km²...
, which caused corresponding changes in the deltas of the incoming rivers, affected the local population of Black Stilts.
Further reading
Database entry includes a range map and justification for why this species is critically endangeredExternal links
- Department of Conservation - Black stilt/kakī recovery plan
- BirdLife Species Factsheet