Helicopter Otago pilot Graeme Gale, of Dunedin, and South West Helicopter's Peter Garden, of Riversdale, were asked by the Island Conservation group to help with the distribution of poison to eradicate rat populations in the Aleutian Islands.
The Aleutian archipelago is a group of about 2000 islands in the Bering Sea between Alaska and Russia.
Island Conservation project manager Stacey Buckelew said Norway rats had destroyed the seabird population on the Aleutian Islands which, at its peak, had reached 40 million to 50 million.
It was hoped the birds would return once the rats had been eradicated.
Ms Buckelew said she had heard about the pilots' work helping to eradicate rats on Campbell Island in the Southern Ocean, and possums in the South Island, and approached them with an offer earlier this year.
New Zealand led the world in terms of programmes to eradicate predators, and the GPS system and bait "bucket" the southern men had developed.
The pilots would fly to Alaska at the end of September, before making a 2000km island-hopping trip to Rat Island in the Aleutian archipelago at the beginning of October.
They would stay on the 2680ha island for 45 days so as to get enough clear days to drop the bait.
The project, costing $US2.5 million ($NZ3.2 million), had been planned for four years.
The eradication of rats on Rat Island would be the first step of up to 15 years of work on the group of islands.
The men, along with pilots from Alaska, would be working in the notoriously difficult Bering Sea and would most likely have to deal with severe storms.
However, it was the time of the year when the rat population was at its lowest, Ms Buckelew said.
