Black stilt
| Black stilt | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Black stilt (Himantopus novaezelandiae) on the Ashley River |
||||||||||
| Systematics | ||||||||||
|
||||||||||
| Scientific name | ||||||||||
| Himantopus novaezelandiae | ||||||||||
| Gould , 1841 |
The Black Stilt ( Himantopus novaezelandiae , Maori Kaki ) is a species of bird in the family of the avocet (Recurvirostridae), which in New Zealand endemic is.
features
In terms of shape, the black stilt is similar to the common stilt , but can be easily distinguished from it by its completely black plumage. In addition, the legs are slightly shorter and the beak is slightly longer than the related species. The legs are pink in color. The wings and back shimmer in a metallic shade of green.
In young animals, the face, neck, and underside of the trunk are white. Even in the second year of life, juvenile black stilts show white spots in their plumage.
distribution and habitat
The black stilt is endemic to New Zealand . While it used to be widespread on both New Zealand islands, it now only breeds in the Mackenzie Basin in the center of the South Island . Outside the breeding season, most of the birds stay close to the breeding area, some migrate to the coast, and very few migrate further and hibernate on the North Island .
Way of life
Black stilts are solitary birds. Their breeding season falls between September and January. Their clutch comprises three to six eggs that are incubated by both partners. The diet consists mainly of the larvae of mayflies , caddis flies , stone flies , dragonflies and mosquitoes, as well as small fish, and more rarely adult insects, molluscs and worms.
Overall, there are extensive similarities in behavior with the common stilt.
Systematics
Some zoologists consider the black stilt to be a subspecies of the common stilt ( Himantopus himantopus ). The common stilt is also represented in New Zealand with a subspecies ( H. h. Leucocephalus ). Occasionally the two species cross, the resulting hybrids are similar to the common stilt, but typically have a black front neck and black spots on the chest and belly.
Threat and protection
There were around 500 to 1,000 black stilts in the 1940s. Predators such as cats and weasels as well as rats and hedgehogs introduced into New Zealand in particular caused the population to collapse by eating adult birds, young and eggs. The drainage of wetlands and the straightening of rivers also contributed to the drastic decline in the population.
In 2001 there were only seven breeding pairs left. Since then, the number of breeding birds has increased steadily through intensive protective measures and was 17 in 2005. With this extremely low number, the black stilt is classified as critically endangered by the IUCN .
The protective measures include renaturation in previously drained areas and active control of predators in the birds' breeding areas. Traps are set up around the nesting areas. 25 black stilts are being kept in captivity, and a release on an island without predators is in preparation.
credentials
- Josep del Hoyo et al .: Handbook of the Birds of the World. Volume 3: Hoatzins to Auks. Lynx Edicions, 1996, ISBN 84-87334-20-2 .
- Himantopus novaezelandiae onthe IUCN Red List of Threatened Species . Retrieved November 19, 2011.
WebLinks
- BirdLife Species Factsheet
- of the DOC on the black stilt with description of the breeding program
- Information on nzbirds.com
- Himantopus novaezelandiae in the Red List of Threatened Species of the IUCN 2008. Posted by: BirdLife International, 2008. Accessed January 31 of 2009.
