The black stilt (Himantopus novaezelandiae) or kakī (Māori) is the world’s rarest wading bird, with their numbers plummeting to just 23 adult birds in the 1980s. Along with predation from introduced predators, competition and hybridisation with the pied stilt has contributed to their population decline. Kakī have been intensively managed since 1981. In 2005, the population had increased to 55 birds in the wild through the Department of Conservation’s intensive management programme. By 2019, the numbers in the wild had increased to 132.
Kakī / black stilt on nest
Braided river status
Once common throughout New Zealand, the black stilt / kakī is now restricted to the braided rivers and wetlands of the Mackenzie Basin, South Island (distribution map) (with two rares exception in the Ashley River estuary). You can see black stilts/ kakī at the Department of Conservation’s captive breeding centre near Twizel. Each pair of black stilt / kakī defends a territory, and nest alone, on stable banks near the water in braided riverbeds, side streams and swamps.
Black stilt / kakī are a compact bird about 40cm long. They are very distinctive with completely black plumage and long red legs. Endemic (unique) to New Zealand, they are regarded by Māori as a taonga species (living treasure). Kakī first breed when aged two or three years, and are known to mate for life. If they cannot find a kakī mate, they may sometimes breed with the pied stilt, a close relative. Juveniles are black and white, their plumage darkening to black as they reach maturity. This can lead to them being mistaken for pied stilts.
‘A day in the life of an aviculturalist‘: the video shows Nick Tomalin, a volunteer with the Kakī Recovery Programme on sabbatical from The Royal Society for the Protection of Birds in the United Kingdom.
Hagen et al (2011) Conservation Genetic Management of A Critically Endangered New Zealand Endemic Bird: Minimizing Inbreeding In The Black Stilt (Himantopus novaezelandiae). The International Journal of Avian Science 153(3):556-561.
Keedwell et al (2002) Predator Control For Protecting Kaki (Himantopus novaezelandiae)—Lessons From 20 Years of Management. Biological Conservation 105(3):369-374.
Maloney & Murray (2001) Kaki (Black Stilt) Recovery Plan 2001–2011. Department of Conservation, Wellington.
Millar et al (1997). Captive Management and Molecular Sexing of Endangered Avian Species: An Application To The Black Stilt Himantopus novaezelandiae and Hybrids. Biological Conservation 82(1):81-86.
Sanders (1999) Effect of Changes In Water Level On Numbers of Black Stilts (Himantopus novaezelandiae) Using Deltas of Lake Benmore. New Zealand Journal of Zoology 26(2):155-163.
Sanders & Maloney (2002) Causes of Mortality At Nests of Ground-Nesting Birds In The Upper Waitaki Basin, South Island, New Zealand: A 5-Year Video Study. Biological Conservation 106(2):225-236.
Steeves et al (2008) Development of Polymorphic Microsatellite Markers For The New Zealand Black Stilt (Himantopus novaezelandiae) and Cross-Amplification In The Pied Stilt (Himantopus himantopus leucocephalus). Molecular Ecology Resources 8(5):1105-1107.
Pierce (1982) A Comparative Ecological Study of the Pied and Black Stilts in South Canterbury. Ph.D. thesis. University of Otago, Dunedin, New Zealand.
Pierce (1984) Plumage, Morphology and Hybridization of New Zealand Stilts Himantopus spp. Notornis 31(1): 106-130.
Pierce (1986) Differences in Susceptibility to Predation Between Pied and Black Stilts (Himantopus spp.). Auk 103(2): 273-280.