An ecologist says the Department of Conservation is planning to spend millions of dollars on extra 1080 poison drops in 2014 to combat a predicted pest boom.
DoC is building a response plan to the so-called mast year in New Zealand's beech forests, in which prolific seeding spurs stoats, rats and mice to breed in greater numbers, threatening local bird extinctions.
The Parliamentary Commissioner for the Environment, Jan Wright, has called for a major tactical response with 1080 drops by early spring.
Dave Kelly, a Professor of Ecology at Canterbury University, says he understands DoC expects to spend about $10 million on its aerial poison programme.
Professor Kelly says it is difficult for the department to juggle its budgets, but it has plenty of advance warning to get ready and plan its reponse.
He says if not checked, the pest boom would be a disaster for some endangered birds, such as the yellowhead, or mohua.
A five-year review of 1080 use by the Environmental Protection Authority has found the amount of the toxin spread for possum, rat and stoat control in forests and on farms has fallen by a third.
A spokesperson for Conservation Minister Nick Smith said he is having DoC prepare a response to recent reviews, and specifically its pest control programme in 2014, but it is too early to say if 1080 use will be increased.