Otago Daily Times
The focus of the postponed aerial 1080 poisoning operation around Makarora appears to have shifted, from rats and mice to possums.

In emailed responses to Otago Daily Times questions this week, Department of Conservation spokeswoman Annette Grieve said the operation would primarily target possums "as rodent populations are likely to have crashed naturally through winter".

Asked for further explanation, Ms Grieve said no-one was available at short notice to answer questions.

While possums are predators of native birds, publicity at the launch of Doc's "battle for our birds" programme, in January 2014, was heavily focused on the effects of rodents and stoats.

Otago Daily Times
Snow has forced the Department of Conservation to postpone the Makarora part of its "Battle for our Birds" programme until spring.

Doc has been planning the aerial drop of 1080 poison on 23,000 ha of the Mt Aspiring National Park around Makarora since last year.

However, in a statement yesterday, Wanaka conservation services manager Chris Sydney said the operation was now scheduled for spring or early summer, with the exact date to be confirmed near the time.

Snow was given as the reason for the postponement.

Otago Daily Times

Possums are the main cause of bovine tuberculosis spreading between herds of cattle and deer, according to Operational Solutions for Primary Industries (OSPRI) which manages the $80 million per year TBfree programme on behalf of New Zealand farmers and the public.

Ospri Group manager new business Peter Alsop told The Otago Daily Times yesterday Tb infection in Possum's"causes about 70% of herd infections".

The remaining infections, he said, were caused by movement of cattle or deer with undetected Tb, but those infections were also likely to have initially been generated by infected wildlife.

Mr Alsop was responding to a suggestion from New Zealand First MP Richard Prosser the Tb problem in possums had been overstated and aerial drops of 1080 poison, targeting possums, were not needed.