Environment Waikato is planning to treat the Whangamarino wetland this month to control bovine Tb-infected possums.
Farmland around the wetland will be treated with ground-based methods such as trapping and bait stations, but the wetland will be aerially treated because of the dense, impenetrable vegetation in the area.
Environment Waikato Biosecurity Group Manager John Simmons said logging of all boundaries will be done with a global positioning navigation system and the work will cover about 1000 hectares. The job will be carried out by Epro Ltd, a Taupo-based specialist animal control company.
“The wetland has impenetrable pampas, willow, flax, rushes and sedge vegetation which makes any other method of possum control extremely difficult. We’ve selected February for the operation to ensure that possum carcasses decompose rapidly and don’t present a risk to duck shooters’ dogs when the season begins in May.”
All surrounding landowners adjoining the aerial treatment area will be visited before the work is done to ensure stock are not at risk. The operation has been given statutory approval by the Medical Officer of Health and Department of Conservation.
“Auckland/Waikato Fish and Game and duck shooters have been fully briefed and support the control programme. We hope to reduce the pockets of very high possum numbers to less than three percent residual trap catch, which is three possums caught per 100 trap nights.”
Mr Simmons said possum control for Tb in the Whangamarino area would be reducing over the next three years with feral animal surveys used annually to confirm that no bovine Tb was present in the area. This would be corroborated by on-going cattle and deer Tb testing in domestic stock.
There are no Tb infected herds in the area, although historically up to four herds have been infected, he said.
Environment Waikato undertakes possum control work for the Animal Health Board, which is responsible for eradicating Tb from New Zealand by 2013.