Thousands of new predator traps have been recently installed in the Godley Cass and Macaulay river systems as part of conservation project, Te Manahuna Aoraki. There is now renewed hope that kakī, the world's rarest wading bird, will one day be able to thrive without human intervention.
Yesterday, 45 juvenile kakī were released at Mt Gerald Station, in the Godley and Cass river systems. Another 19 birds will join them this afternoon, while a further 66 were released into the Tasman Valley earlier in the week.
DOC Senior Biodiversity Ranger Dean Nelson says until recently the young waders have been released in the Godley and lower Cass Valleys with only very limited trapping to protect them from predators like stoats, ferrets and feral cats.
"We're delighted to be able to release 64 birds here, safe in the knowledge the increased trapping system will help to keep most predators at bay.
"Previously fewer than 30% of the young birds released in the Godley and lower Cass valleys were surviving to become adults whereas in areas with significant trapping like the Tasman valley, the survival rate is 50%," he says.
Chair of Te Manahuna Aoraki Dr Jan Wright says DOC and other organisations have done a fantastic job of bringing kakī back from the brink of extinction.
"Over the last six months Te Manahuna Aoraki have laid more than two thousand new predator traps, so 80% of the current kakī range is now protected."
Te Manahuna Aoraki has more than doubled DOC's existing trapping network area, from 26,000ha in the Tasman valley, to more than 60,000ha across the kakī range.
The birds have been hatched and reared for release by DOC and The Isaac Conservation and Wildlife Trust. The juvenile kakī are released into the wild at nine months old, and reach adulthood just over 12 months later.
"I'm told kakī start squabbling like teenagers at about nine months so it's the right time to release them into the wild, and it is wonderful to know these birds will have their best chance yet to survive through to adulthood," says Jan Wright.
"The other threatened birds that breed in these braided rivers like wrybill/ngutu pare, black-fronted tern/tarapirohe, banded dotterel/tūturiwhatu and black-billed gull/tarāpuka will also greatly benefit from the extended trapping network," she says.
Kakī are only found in the braided rivers and wetlands of the upper Waitaki and Mackenzie basins, although they can occasionally be seen in other parts of the country. It is one of New Zealand's most threatened birds.
The Department of Conservation has intensively managed the highly threatened birds since 1981, when their population declined to a low of just 23. There are now 129 adult kakī living in the wild.
Background information
Kakī/black stilt
There are currently 129 adult kakī in the wild and thirty adult pairs successfully laid eggs last season. Unfortunately, frequent flooding and cold weather in the braided rivers affected last season's breeding rate.
A record 184 juvenile kakī were released into the Mackenzie Basin last year and these birds will reach adulthood in September 2019. It is hoped the adult population will increase at the next kakī 'count'.
During the breeding season, eggs are harvested from both wild and captive pairs. They are incubated at the DOC Twizel facility and hand reared either in Twizel or at The Isaac Conservation and Wildlife Trust in Christchurch.
The birds are then released as juveniles or sub-adults, an age when they are less vulnerable to predators. This management method has seen the population significantly grow over time.
Young kakī are normally chased away by their parents prior to the breeding season and the squabbling between them is part of this stage. By releasing the birds prior to the breeding season, we are following that natural process.
48 birds released this week were reared in a new Twizel aviary funded by Global Wildlife Conservation.
The Isaac Conservation and Wildlife Trust was founded by Sir Neil and Lady Diana Isaac in the 1970s as part of their commitment to conservation. The Trust assists in breeding programmes for endangered native birds and other species. It currently breeds kakī/black stilt, pāteke/brown teal, whio/blue duck, kākāriki karaka/orange-fronted parakeet, New Zealand shore plover and skinks at its wildlife breeding facility at Harewood.
The Trust has supported kakī recovery for 25 years and raised many hundreds of young birds at their captive breeding centre in Christchurch. This year the Trust has raised 45 young kakī for release.
Te Manahuna Aoraki conservation project
Te Manahuna Aoraki is a large-scale conservation project focused on restoring the iconic natural landscapes and threatened species of the upper Mackenzie Basin and Aoraki National Park.
Te Rūnanga o Arowhenua, Te Rūnanga o Waihao and Te Rūnanga o Moeraki, the Department of Conservation and NEXT Foundation, are the project's founding partners. They are joined by high country landowners, and investors Aotearoa Foundation, Jasmine Social Investments, Global Wildlife Conservation (GWC) and Predator Free 2050 Ltd.
The project includes both private and public land – high country run holders, government departments, philanthropists, iwi, councils and the community are all working together towards a common vision.
The project involves a $4.5million three-year interim phase to extend protection for kakī and other endangered species and to test tools and techniques for a proposed 20-year landscape scale predator-free area.
