New technology boosting predator free fight
This article was originally written by our Board Chairperson Tim Pankhurst and published by The Post on 20 July 2024. See original article here.
Capital Kiwi chair Dame Kerry Prendergast with kiwi chick Pāpango. Courtesy Sara Tansy / Capital Kiwi
Every week a group of old geezers gather at a former bowling club greenkeeper’s shed in Hataitai. Here they saw and hammer and snip and laugh and yarn while they make rat traps – hundreds of them. The group meeting under the banner of MenzShed Wellington includes community stalwart Chris Hare.
“I was catching 300 rodents a year,” Hare, 69, says. “That has come to a crashing halt this year, I’m down to about 30.”
His wife Anne Hare, a former Olympian who still holds the New Zealand women’s 2000m running record, sometimes accompanies him when checking traps but usually prefers to keep moving.
“We’re actually putting ourselves out of business,” Hare says, “ but now we’re making traps for other areas.”
Mitre 10 Crofton Downs, one of many businesses and organisations supporting the rewilding of Wellington city that includes lawyers Russell McVeagh, production company Kiio, Fix & Fogg’s peanut butter and the Nikau Foundation, has been generous in providing materials. The group also has an eye out for demolition timber. Fence palings are snapped up.
Hare says the impact of Predator Free Wellington employees moving across the city now that Miramar Peninsula has been cleared of rats, stoats and weasels has been huge. He now has tūī, pīwakawaka and kereru in his Waipapa Rd backyard garden and kaka flying overhead. Hare’s MenzShed mates are one of 63 volunteer groups across greater Wellington with a collective membership of several thousand who are actively trapping. Wellington City Council supports the work in their parks and reserves.
Predator Free Wellington staff are now well advanced on phase two across 11 suburbs from Owhiro Bay north through the CBD to the harbour before pushing further east to finish the job. Where there has been active backyard and reserve trapping, the population of target predators has been reduced. But it is not until the PFW team come in with traps and toxins that only the professionals can use, combined with rapid cycles of device management, that elimination can be achieved.
The explosion of native birdlife across the city beyond the sanctuary of Zealandia is complemented by the Capital Kiwi Project’s restoration of our national bird to the wild west of Wellington city. From March to May this year another 75 kiwi were relocated to the hills of Makara – 65 from Sanctuary Mountain Maungatautari in the Waikato and 10 from Rotokare in Taranaki. That brings the total number of kiwi released in the 23,455-ha expanse from Red Rocks through to Porirua to 138 adult birds.
The deployment of 4600 traps across that landscape has reduced predators, principally stoats, to the extent of allowing the safe relocation of kiwi, which have begun breeding in their new home among the manuka and the gorse. Twenty kiwi that are being closely monitored have survived and the project’s first wild-born chicks have reached 1.2kg, the weight at which they can fight off stoats.
Breeding programmes within fenced sanctuaries have been so successful they now need to export birds. As many as 300 need to be relocated each year from Maungatautari, with many likely to be Wellington bound.
Field officer Jed Prickett checks a trap and bait station in Evans Bay. Courtesy Nikki MacDonald / The Post
“The scale of birds being available to re-wild kiwi is a radical shift in the pace and scope, of the guardianship of our taonga and icon” says Capital Kiwi founder and project lead Paul Ward. “It’s incredibly fortuitous for us. Thanks to epic pest removal efforts of locals, iwi and landowners, Capital Kiwi is by far the biggest new addition of land available to kiwi conservation. It’s almost a blue sky scenario.”
Kiwi are also thriving in the Wainuiomata catchment and venturing into Upper Hutt as well as suburban backyards. Across the country, new technology is being developed to clear areas of predators more cheaply and quickly.
A trial of new bait stations and dispensers began on Mt Victoria this week.
It involves a large network of robust and secure tunnels that contain newly developed H2-Zero dispensers, both produced by Zero Invasive Predators, a company supported by the Next Foundation established to remove rats, possums and stoats from large mainland areas.
The dispenser uses a hydrogen producing coin cell battery that allows the gas to expand, inflating an air cell that pushes down on a syringe to gradually extrude 125 ml of lure over a three-month period. The lure contains rat toxin. The major benefit of this method is that the devices can be left for several months, allowing the removal of many rats for little effort.
Around 30 trail cameras are being used to monitor the rat population as it declines and to see how effective the new method is and detect any animals left behind. They will also be used to observe rat behaviour and how they interact with the stations.
Another innovative first is a phase two buffer and barrier system along a 7km stretch through the central city from the south coast to the harbour comprised of over 1000 lethal devices – traps and bait stations – to prevent ingress of target species into the elimination area. This defence system is entirely led, managed and maintained by up to 200 trained volunteers.
AI cameras are also due to begin field trials. These will simplify the time consuming task of trawling through the 380,000-odd images produced annually by the network of 500 cameras to detect any re-invaders and identify animals.
Posted: 20 July 2024