Mutant possum, drones on horizon

The Department of Conservation is pursuing research into mutant possums which produce infertile male babies and aerial drones which use infrared technology to target pests.

The department's director-general, Lou Sanson, spoke to Nelson staff yesterday as part of a tour around regional DOC offices.

He said large-scale pest control was the biggest practical conservation issue facing Nelson, saying DOC was researching both more efficient ways to use 1080 and alternatives to the controversial pesticide. "It's the most practical tool we've got," he said.

Mr Sanson said there was "good science" which had successfully demonstrated that 1080 had minimal impact on non-target wildlife, but New Zealand had such a large problem with introduced predators that DOC needed more options.

One such tool being developed by Landcare Research and Otago University was the "Trojan female" possum.

Mr Sanson said the "Trojan female" would reduce the number of possums in the wild by only giving birth to sterile males.

It had been created through genetic mutations. "We're definitely investing in this," he said.

He said there was a concern that the mutant possum would be introduced to Australia and affect their native possum population.

But he understood it would need to be continually re-introduced into the breeding pool.

The same partnership had also developed an aerial drone which can locate possums using infrared technology.

Mr Sanson said both projects would be presented in Wellington over the next few weeks.

But it was difficult to know when they would be rolled out in the field.

Mr Sanson said that this year promised to bring an exceptionally heavy beech "mast" or flowering, which would mean a corresponding boost in rodents and, subsequently, stoat numbers.

Strategic 1080 drops would take care of this, but no decisions had been made as to when this would happen.

DOC began a 1080 programme in the Kahurangi National Park last month, which will continue until June 30.

"1080 is the most practical tool we've got," Mr Sanson said. "We must protect the gains we've already made in our large ecosystems."