You are not permitted to download, save or email this image. Visit image gallery to purchase the image.
The department confirmed this week the predator control operation, which will cover about 24,000ha in the Dart, Routeburn and Caples Valleys, will begin on August 25.
Part of a South Island-wide operation that will cover about 70,000ha, its aim is to protect threatened bird species from a population surge of rats and stoats after a heavy seeding of beech trees - known as a ''beech mast'' - during the past summer.
Doc's conservation partnerships manager for Queenstown, Greg Lind, said the operation had been timed to ''knock back'' rats and stoats at the early stages of their population boom, and would be completed well before the walking season began.
Monitoring surveys of rat and mice numbers showed there was a ''major predator eruption'' in the three valleys similar to that following a beech mast in 2011.
There had been no aerial 1080 operation in 2011, and the local population of mohua was ''almost eliminated''.
Other bird species in the upper Wakatipu vulnerable to rising predator numbers included whio (blue duck), kaka, kakariki, tuke (rock wren) and kea.
The helicopter operation would take place over two days, separated by at least a week, with the first drop being a ''pre-feed'' of pellets not containing the toxin.
The exact dates of the operation were dependent on the weather, as fine and calm days were essential, he said.
All walking tracks in the three valleys would be closed for both bait drops, while tracks in several side valleys would also be closed, including Fraser Creek, Kay Creek, the Routeburn North Branch, Rock Burn and Beans Burn.
Doc was keeping affected groups up to date with the operation, including landowners, runanga, businesses with concessions in the area and hunting and outdoor recreation groups.