Mice poison risk to wildlife Expert

A Martinborough conservationist, author and recognised expert on native parrots has come out strongly against plans to eradicate mice on off-shore islands using brodifacoum poison.

Bill Benfield said a website for the Million Dollar Mouse campaign looked so "harmless and innocent" schools were holding sausage sizzles to help raise money to fund the campaign.

"But there is nothing on the website to show children, and other donors, the mice will be eradicated by poison, an aerial drop of brodifacoum."

Mr Benfield said brodifacoum, a second-generation anti-coagulant, is a poison known to cause "ecological disruption" to rare birds and sea life.

"Would children willingly raise funds if they were aware rare parakeets would be poisoned and die agonisingly and slowly over 20 days?

"Brodifacoum is extremely long living in the environment, with a half-life in the soil of around 160 days.

"It is a slow, cruel, callous killer," Mr Benfield said.

The Million Dollar Mouse campaign is a project supported by businessman and conservationist Gareth Morgan, who has also made headlines this week with his campaign to eradicate cats from New Zealand.

The campaign is seeking funds to support the project to eradicate mice in the Antipodes Islands.

But Mr Benfield claimed brodifacoum had caused deaths of marine animals, including dolphins and penguins on Little Barrier Island and Rangitoto Island.

He said insect-eating birds such as fantails and predators such as owls, magpies and hawks "disappear" following brodifacoum use yet rats are back within a year "often in greatly increased numbers".

DoC confirmed the department's preference was to use brodifacoum to eradicate mice on the Antipodes Islands.

Media adviser Reuben Williams said the Million Dollar Mouse campaign was still at the proposal stage and funds were being raised for it.

"DoC mainly uses brodifacoum on off-shore islands as a one-off eradication method for rodents, which is the most effective toxin for this type of work."

Mr Williams said DoC has "a good record of practice" in the use of brodifacoum for pest control and takes a "precautionary approach" to minimise impacts to native species and public health".

"DoC accepts there will be some impacts on native species, however the benefits to wildlife by removing rodents from off-shore islands are far greater than potential impacts," he said.

He said after brodifacoum operations there had been "long-term" gains for biodiversity and an increase in wildlife populations. Examples of this were on Rangitoto, Motutapu, Kapiti, Whenua hou/Codfish and Campbell Island.