The southern march of wallabies into Otago is being challenged by a major eradication effort to stop the invasive pest before it takes hold.
A 2022 search found wallaby scat at numerous locations across the Flagstaff area, including Silverstream, Whare Flat and Swampy Summit.
Since 2011, there have been 22 reported wallaby sightings in the Dunedin area.
Now, Otago Regional Council has contracted High Country Control to lead the operation to control the invasive animals.
The Biosecurity New Zealand-funded operation, supported by Dunedin City Council Parks, Department of Conservation and City Forests, is under way.
Biosecurity NZ co-ordinates the Tipu Mātoro National Wallaby Eradication Programme.
The operation will be phased, with surveillance in separate areas from now and into 2026, beginning with City Forests.
Detection methods include indicator dogs, thermal drones, and trail cameras, with signage and QR codes at public land entrances for recreational users.
The operation covers 8300ha, divided into five areas, though no operations will start without consultation with affected landowners and stakeholders.
Control methods may include shooting or using toxins and will depend on where wallaby are found and public safety risks.
ORC’s project delivery specialist Gavin Udy said wallaby could have a massive impact on primary industry and native biodiversity.
“Otago has a chance of eliminating this pest as they are still in relatively low numbers here,” he said.
“The Flagstaff and Silverstream area are highly forested, with popular recreation trails used by the public for mountain biking, dog walking and trail running, so we’ll be installing signage to let people know local contractor High Country Contracting will be in the area and that we are tracking wallaby.”
Dunedin City Council pest control contracts manager Kate Tanner said the operation was a good chance to remind the public that wallaby are present, and threaten precious native flora and fauna.
Shane Pearce, ranger biodiversity threats at DoC, said the work was essential to protect the unique biodiversity values of the area, as well as wider community expectations of a healthy eco system.
Bennett’s wallaby foul pasture, damage fences, destroy crops, contribute to erosion, and compete with livestock, as well as prevent the regeneration of native bush, deplete forest understories, and browse/kill seedlings of some plantation forest species.
High Country Contracting will contact landowners for permission agreements and discuss access.
Where wallabies are found, contractors will consult with consenting landowners before control work, and no control will occur without permission.
Wallabies are banned under the Biosecurity Act, with heavy fines for breeding, selling, or moving them.
John Walsh, Biosecurity NZ director - pest management, said in the past 12 months there have been two wallaby sightings near Te Anau, though no wallabies or wallaby populations were found.
Four more sightings have been reported to the programme in Southland in the past year, close to Otago and West Coast regional boundaries.
There have been 26 reports in Southland in the past five years.
No wallabies were found with any of these reported sightings.
Wallabies are a highly mobile invasive animal with North and South Island populations estimated to spread up to 2km a year.
If left uncontrolled, they could cost $84 million annually and occupy a third of NZ by 2065, according to Biosecurity NZ.
Ben Tomsett is a journalist based in Dunedin. He joined the Herald in 2023.