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Published: 2007-01-16 00:00:00

A major possum control operation is planned for the Pirongia-Otorohanga area in order to create a buffer zone around Mt Pirongia for conservation and agricultural production control purposes. 

The operation is part of a new five-year programme from Environment Waikato to expand pest control in the region. It will involve a consultation process with affected landowners over the coming months, and is planned to start in the middle of 2007 and go on through into early 2008.

The project is a collaborative effort between Environment Waikato, the Department of Conservation and landowners, and aims to reduce possum densities to very low levels across the north-west King Country area.

“Mount Pirongia is considered one of the top ecological sites in the Waikato, with native birds such as tui, bellbird and kereru, and some of the most magnificent stands of native bush in the region,” says Environment Waikato’s biosecurity operations manager, Peter Russell.

“The mountain last received extensive possum control in 2002, and is now due for re-treatment in 2007. The aerial operation in 2002 was very successful, and it has helped the forest to recover, as well as increasing the numbers of native birds. However, this recovery will not last unless we return periodically to control possums and other pests.”

Mr Russell said that recent monitoring showed that possum numbers were starting to increase on Pirongia. Possum palatable trees, such as kohekohe and kamahi, show clear evidence of possum impacts. Possums, together with stoats, ferrets, feral cats and rodents, also prey on a wide range of wildlife on Pirongia.

“On Mount Pirongia, aerial control will need to be carried out using 1080 baits, as this is the most practical and cost-effective control method for this rugged and steep country,” he said.

“Helicopter sowing of baits using satellite navigation technology allows the pilots to be sure of the boundaries and to exclude important areas, such as roads and water intakes, from being sown with baits.”

Control methods for private land adjoining the main mountain will be discussed with landowners, and may include a mixture of the ground-based control, bait stations, aerial control, other toxins and traps.

Mr Russell said the operation would cover Mt Pirongia (14,500 ha), the buffer zone around the mountain (15,400 ha) and the adjoining areas of Oparau (11,333 ha), Ngutunui (6,400 ha), Waipa-Puniu (10,600 ha), Hauturu-Awaroa (8,775 ha), and Honikiwi (6,870 ha).

“This will result in possums being controlled on most of the land west of and between Pirongia and Otorohanga townships, an area approximately 74,000 hectares in size and involving 700 landowners,” he said. “This will reduce possum reinvasion from untreated areas and consequently reduce the frequency and costs of future possum control operations.”

Mr Russell said it was important to give farmers early notice of the proposed operation, as it allowed them to plan their stock rotations with plenty of advance notice.

“We will be meeting with existing landowner steering groups and developing relationships in the new control areas to seek feedback on the proposed control operations,” he said. “In addition, there will be consultation with iwi and community restoration groups in the area as well as other stakeholders, such as forestry companies.

“Individual landowner consultation will take place before any work will happen on an individual's property. This would involve contractors making contact in advance and discussing the control methods that could be used on a specific property and what is being planned for neighbouring areas.”

The total cost of the possum control operation is expected to be $1.2 million, with the Department of Conservation paying approximately one third of the total cost. This reflects the Crown’s recognition of the national benefits that will come from this work. The remaining two-thirds of the cost will come from regional rates spread across Environment Waikato’s entire area.

At the moment about 70 per cent of the Waikato Region benefits from pest control work done by Environment Waikato and others. The proposed five-year plan would increase that figure to 90 per cent, adding another 600,000 ha to the area already covered. Not all of this work would be done by Environment Waikato, which is why effective partnerships such as the Pirongia operation are so important. Details of the full five-year proposal will be available in the draft Regional Pest Management Strategy to be released in March.

For more information on the Pirongia operation, contact Peter Russell or Dave Hodges at Environment Waikato on 0800 800 401, or Dion Patterson at Department of Conservation on 07 838 3363.

Possums Are a Menace

Possums are a menace to New Zealand's native bush - as well as damaging pasture, plantation forests and homeowners’ fruit trees and gardens.

  • Possums carry bovine Tb. By keeping possum numbers low the disease dies out in the possum population, protecting stock. No-one wants a bovine Tb outbreak in the area.
  • Possums will also compete with stock for grazing. Ten possums can eat as much grass as one sheep in a night.
  • Possums destroy native bush by eating the leaves, fruit and flowers, as well as preying on native insects. This means there is less food for our native animals.
  • Possums will also eat the eggs and chicks of native animals. Getting rid of possums allows our forests to regenerate and remain healthy.
  • Possums are a nuisance because they don’t just stay in the bush. As many homeowners know, possums will come into your gardens, eat your fruit and flowers and jump on the roof at night.

That's why we need to keep the possum population in your area under control - which is why Environment Waikato and the Department of Conservation are proposing to launch a large scale control operation in the Pirongia-Hauturu area.