Halo of happiness for Dunedin birds
The vision of Dunedin a decade into the future is a unique wildlife-friendly city defended by a wide halo of healthy greenery.
It’s a picture in the minds of everyone involved in creating Predator Free Dunedin, a ground-breaking collaboration between conservationists, councils, companies and citizens, a city-wide project to turn Dunedin into a predator-free wildlife paradise.
Predator Free Dunedin is a unique collaboration involving 20 organisations that will contribute to the three-part 31,000 hectare project. The Predator Free Peninsula project targets possums across 9,000 hectares and aims to eradicate possums from the Otago Peninsula by 2023. The group leading this work, the Otago Peninsula Biodiversity Group (OPBG), have trapped 18,044 possums since March 2011 and are now working on targeted “hotspots” -- areas of habitat which possums find favourable.
On the other side of the city is the 12,500-hectare Halo Predator Free Project. Landscape Connections Trust, in collaboration with Orokonui Ecosanctuary and OSPRI’s TBfree work, is working with residents to roll out a predator-trapping programme that will reach into the fringes of Dunedin City.
The third component project is called the Urban Linkage. This includes the urban part of Dunedin City that links the two landscape-scale projects and will eventually constitute a predator-free ring around the harbour. A planning team from DCC, DOC and PFD is refining the implementation plan for this new project, including the recruitment or Urban Linkage coordinators to engage with residents.
Predator Free Dunedin is new ground for OSPRI, the company charged with eradicating bovine tuberculosis from New Zealand through the TBfree programme. The programme involves reducing and managing possum numbers, so working with a community towards reducing other predators is a clever collaboration.
Working with The Halo Project, OSPRI is creating the infrastructure for long-term pest control which will pay dividend long after the TBfree programme’s eradication goals are achieved. The knockdown of possums required to interrupt the cycle of infection in wildlife and stop TB infecting the area’s cattle and deer herds is a powerful first blow in the bid to protect the birds and bird habitat in the hills surrounding Dunedin’s jewel of a harbour.
OSPRI’s TBfree operations in the region involve large scale possum control operations around Mt Cargill, where TB infection was identified in five herds, over the hill and around the fence of Orokonui Ecosanctuary and out towards the coast. At Flagstaff, more than 1000 possums have been removed since March 2019 adding to the 16,000 removed since the operations around Dunedin began in 2018.
The 12,500-hectare Halo Predator Free Project fits in well with Orokonui and OSPRI’s TBfree work. OSPRI have been working with the Halo Project to boost possum trapping efforts in the urban areas next door and once OSPRI achieves TB eradication, the biodiversity gains achieved through the possum control will then be continued by the Halo Project.
The Halo Project at work
Halo Project operations manager Jonah Kitto-Verhoef is back on home turf after a stint working on Waiheke Island in the Hauraki Gulf.
The North Otago native works from a small office in Port Chalmers with two project coordinators, Sanjay Thakur and Kate Tanner. They organise and galvanise about 150 active volunteers and many more backyard trappers. Across the project area, volunteers set and monitor about 400 stoat traps and more than 200 possum traps.
It’s a powerful operational force for restoring habitat and increasing bird numbers.
“What’s really impressive is that one-in-five households are involved, giving their time to get and keep possum numbers down to low levels (2% residual trap catch index) – that’s a really good level of support for any community undertaking.”
Project members monitor rodents with tracking tunnels and undertake lizard, little blue penguin and South Island robin monitoring. To increase visibility of animal traffic in the area, there’s also a trail-camera trial underway with Manaaki Whenua Landcare Research.
“We recently completed stoat trap installation across the 3900 hectare area at one trap per 9.1 ha. That’s almost a third of the total Halo area so it’s a very significant milestone for the project,” Jonah says.
Residential possum trapping is now occurring in Port Chalmers, Sawyers Bay, Pūrākaunui, Osbourne, Waitati and Doctors Point. Since the project started, 108 possums were removed from these residential areas in June alone.
“We’re really excited to see the OSPRI rural possum operation moving back through much of the project area over the next few months.” A Project Halo flyer was included with a recent mailout of OSPRI’s TB Management Area newsletter.
OSPRI has been working with the Halo Project to reduce possums on the tricky harbourside slopes and coastal forest ecosystems that surround the Orokonui Ecosanctury. Many of the native species are vulnerable to predation and the spillover of native birds from the safety of the predator-fenced sanctuary into the wider landscape is happening.
Eighty-six traps have been established in Purakaunui and local resident Katrina McKenzie says results are apparent already. “I’d say it’s been really successful – since the wider OSPRI knockdown combined with local trapping, we’re not hearing or seeing signs of possums. We’re getting roses in the garden and fruit back in our orchards again,” she says.
OSPRI’s disease eradication programme continues this year. Eric Chagnon, Programme Manager says “We’re making real progress controlling TB around Dunedin and all herds are currently healthy. We need to keep our possum control up for a couple more years to get rid of the disease. Putting an end to the disease benefits everyone and working with the Halo Project means we can leave a legacy for native wildlife for years to come.”