Conservation of the black stilt http://ibc.lynxeds.com/photo/black-stilt-himantopus-novaezelandiae/new-zealand-rare-endangered-black-stilt
Jul 10, 2015
Conservation of the black stilt
http://ibc.lynxeds.com/photo/black-stilt-himantopus-novaezelandiae/new-zealand-rare-endangered-black-stilt
Black stilt / Kaki
• One of the rarest wading birds in the world
• Endemic to NZ
• Plumage is completely black
• Long red legs
http://en.wikipedia.org/wiki/Black_Stilt
Black stilt / Kaki
• Mate for life
• Sometimes mate with the closely related pied stilt (Himantopus himantopus)
• Live in braided rivers and wetlands
• Distribution – once common throughout New Zealand, now only found in braided rivers of the MacKenzie Basin
Black stilt / Kaki
• IUCN status - critically endangered
• Population size – declined to as little as 23 birds in the wild.
• Managed since 1981
Threats• Habitat loss – the drainage of wetlands and channalisation of
rivers
• Predation – introduced of mammals such as cats, ferrets and hedgehogs.
• May also be increased by 1080 control on rabbits populations (Wallis, 1999)
• Recreational users of rivers and wetlands
• Fishing and walkers - crushing of eggs and chicks
• Jet boats – scare adult birds away from nests.
Vulnerability increased due to:
• Timing – black stilt chicks are born earlier than other chicks
• Length of fledging – chicks are dependant for 39-55 days before fledging.
• Nest alone rather than in colonies i.e. less protection
• Hybridisation with pied stilts - can reduce the number of offspring with 'pure' black stilt genetics.
Conservation by numbers
• Intensive management of the black stilt began in 1981.
• Department of Conservation (DOC) opened a captive breeding centre near Twizel and by 2005 the number of wild Kaki had increased to 55.
• Kaki Recovery Programme hatched 139 chicks in the 2013/2014 season and estimate breeding adult numbers to be between 58-78.
Conservation Efforts• Removing eggs from nests to promote relaying by parents.
• Controlling water levels in managed wetlands
to encourage bird feeding and breeding.
• Trapping of predators around known nests.
• Captive breeding
• Predator proof fences
http://docnz.files.wordpress.com/2013/05/cody-glen-juvenile-kaki-release.jpg
http://blog.doc.govt.nz/tag/kaki/
Successful hatchings of the 2012/2013 season
Release of captive bred sub-adult birds into the wild
http://blog.doc.govt.nz/tag/kaki/
Problems with captive reared Kaki● Iodine deficencies - the cause of death in hatchlings,
embyros and released sub-adult birds.
● Pododermatitis – a disease common in the feet of the captive bred birds
● Migration - birds migrate from desired sub-populations after being released into the wild.
Possible future conservation
● Establish a self-sustaining population on a predator free offshore island
● Continue with current monitoring
To summarise...● 30 years of work by New Zealand's Department of
Conservation and the community within the MacKenzie Basin has prevented the extinction of the black stilt.
● The population is slowly recovering through captive breeding and other conservation efforts.
● Black stilts are far from safe from the risks of extinction.
● Slow increases in population size means ongoing conservation will be required for some time.