AN intensive exercise spanning four days and nights, involving more than a dozen volunteers and specialised experts and requiring a great deal of covert activity, ended in the hills of Manawahe last month with the mission’s six targets successfully released into a new wilderness – the targets, three pairs of precious endangered native forest kokako.
Captured from their home in the Kaharoa forest near Rotorua, the six birds were relocated to Manawahe in the hope they will bring genetic diversity to the small remnant population of kokako who, largely due to the efforts of the Manawahe Kokako Trust who have worked tirelessly to protect the birds for the past 21 years, survive in the bush-covered hills there.
Trust member John Whale says by introducing the new gene pool, the trust is hoping to prevent, or cure, a situation known as a genetic bottleneck.
The Manawahe Kokako Trust was formed in 1998 after landowners Wendy Montrose and Ross Dredge first discovered seven pairs of breeding birds in an area between McIvor and Manawahe roads, but despite a period of growth that saw the birds increase to 16 pairs by 2009, recent years have resulted in an inexplicable decline, with numbers now down to six pairs.
John says that although there are numerous habitat and predator factors that could be affecting the bird’s ability to successfully breed, a genetic bottleneck is the main contender.
“We’ve found deformed and infertile eggs and experts tell us that it can be because there are no new genetics coming in. With just six pairs of birds in Manawahe, that’s the risk.
They are a relic population and through inbreeding, they may have lost their genetic vigour.”
He says the trust is hoping that bringing new birds in from a different area will address the problem.
John says the translocation of the birds was a complex and lengthy operation requiring expertise from outside the trust. “It was a first for us, we’ve never done it before, but we had huge support and guidance from the Department of Conservation and the Kokako Specialist Group.”
He says the trust had to apply to the Department of Conservation for the translocation, a process that spanned two years. “At the same time, we applied for funding grants, and with assistance from QEII, we got Lotteries Commission funding to pay for equipment to carry out the work and specialists to actually capture the birds and monitor them following release.”
He says support from the Bay of Plenty Regional Council with pest management equipment was also a major factor in the success of the application.
Trust member Ken Laurent says the actual translocation process involved identifying the approximate location of kokako pairs in Kaharoa Forest, then creating 12-metre clearings in those areas. Mist nets 30-metres high and 12 metres wide were erected to intercept the birds as they flew in responding to loud-speakers playing pre-recorded kokako calls in their own dialect.
“Kokako are very territorial, so they’ll usually come to check out who is singing in their territory,” Ken says. “It was a long process requiring dedication and patience.” Along with eight other volunteers from the Manawahe Kokako Trust, Ken and his wife Sue were putting in 12 hour days in preparation for the capture. “But it was a very special time.”
“On the Sunday before we started capturing birds, we had a powhiri with local iwi and members of the Kaharoa Kokako Trust and that was a very powerful and moving hui.” He says the actual capture of the birds took place early morning, sometime before dawn.
“It’s just stunning to be in the middle of the forest, to hear the call go out and hear a call come back and then having the birds fly in.” He says more than one person had water running down their faces, “and it wasn’t raindrops.”
Kokako are considered to be part of an ancient family of wattlebirds endemic to New Zealand. Maori myth tells of a kokako filling its wattles with water and taking it to Maui as he fought the sun.
“They have the most beautiful song,” Ken says of the kokako’s extraordinary call, commonly described as rich, sonorous, organ-like, and haunting.
He says as the birds were caught, they were weighed, measured, and fitted with leg bands and tiny transmitters to enable their locations to be monitored. The kokako were then “put in cosy boxes for the ride from Kaharoa to Manawahe and released as swiftly as possible”.
He says the special tiny transmitters are designed to fall off in a couple of months.
“We are hoping that bringing the new pairs to Manawahe will create a genetic asset, valuable in helping to ensure the birds’ long-term survival.”
Meanwhile, the Manawahe Kokako Trust will continue the tasks it has been carrying out for years, with its 20 odd volunteer members working to keep the area as free as possible from pests that threaten kokako survival; possums, stoats, and rats.
“We monitor around 700 bait stations and 70 traps, so it takes a bit of work,” says John.
“But it’s enjoyable work and it keeps you fit. We have a great bunch of people and the forest is a wonderful place spend your time.”
North Island kokako have long been in significant decline, but over the past 20 years, conservation and pest control work has reversed the trend in some areas with kokako now officially reclassified from threatened, to at risk-recovering. All recovering areas are considered to be the result of the efforts of volunteer groups such as the Manawahe Kokako Trust.
South Island kokako are now considered extinct. “A sad fact,” says John, “which gives us strong motivation to protect their remaining North Island cousins”.
Kokako open day
AS part of the Birds-a-Plenty Festival this year, the Manawahe Kokako Trust will hold an open day on Saturday, September 21.
This day provides the public with an opportunity to walk through native bush tracks and hear the hauntingly beautiful song of the rare and endangered North Island kokako, and hopefully, get to see them too. A light barbecue with tea and coffee will be held afterwards.
Details regarding the early morning meet up time at Manawahe will be given on registration.
To register, phone Jude Hays on 07 3088473 by Wednesday 18. Cost is $5 a person, minimum age 12 years. Moderate fitness and good footwear required.