More 1080 poison drops are scheduled for more than 720,000 hectares of land as part of the largest pest control operation in New Zealand's history.

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The government launched the $20.7 million programme in Queenstown this morning.

The poison will be dropped over 19 sites, covering about 10 percent of the conservation estate.

It is part of the Battle for our Birds programme started by the Department of Conservation (DOC) in 2014 to help tackle the high number of predators of native species.

Warmer weather has resulted in a heavy seedfall, or mast, in the country's beech forests over autumn resulting in an abundance of food for stoats and rats, which breed and prey on native species.

Earlier this year, the Conservation Minister Maggie Barry said these predators were likely to reach "biblical proportions."

Today she said doing nothing about this was "not an option."

Photo: Supplied

"We'll not only be saving 12 priority species from the real risk of local extinction but the landscape-scale pest control will support the entire native ecosystem," she said.

Those species included the North Island brown kiwi, short-tailed bat, the Kea, Kaka, Whio and the Rock wren.

The first drop will take place in the Kahurangi National Park next week.

As well as the drop over parts of the North and South Island, another 10 sites covering 200,000 hectares will be monitored for rodent numbers.

The poison may be applied to those areas if pest numbers reach levels that threaten local populations of native species.

According to DOC, 1080 is biodegradable, breaks down quickly in the environment and does not leave permanent residues in water, soil, plants or animals.