A $35 million to $50 million proposal to eradicate rats, wild cats and possums from Stewart Island has been released to the community for consultation.
The feasibility study was released to the public this week and the 139-page document is the first of many steps towards eradicating pests from the island, Stewart Island-Rakiura Community and Environment Trust spokeswoman Jo Learmonth said.
"The question for us is `can it be done?' and there are a lot of issues that need to be discussed before we go ahead."
One issue which angered some residents was the possibility deer repellent be added to an aerial bait drop, but this idea had been been quashed, Mrs Learmonth said.
"Overall, our support from the public has been very good. People agree with the concept but they are keen to know what impact it would have on them."
Last year, the trust secured funding from the Tindall Foundation to investigate the possibility of eradicating rats, wild cats and possums from the island.
The feasibility study - Scoping the Potential to Eradicate Rats, Wild Cats and Possums from Stewart Island-Rakiura - sets no timeframe for eradication, but it could be from five to 50 years, "depending on when the community wants it", she said.
The project, which it is believed would be the largest pest eradication ever undertaken worldwide, could cost between between $35 million to $50 million, and would require more than 4000 tonnes of bait.
Who would fund the plan was yet to be decided, Mrs Learmonth said.
"We want approval from the community before we approach funders."
Current biosecurity for the island costs more than $400,000 per year.
Other recommendations in the report include aerial application of brodifacoum bait, the construction of a predator-proof fence around the township, and rodent-detecting dogs at departure points to the island.
The report notes the absence of stoats, ferrets, weasels, mice, goats, pigs, wallabies, hares and rabbits have placed the island in a fortuitous ecological position compared with the rest of New Zealand.
The eradication of rats, wild cats and possums would enhance the reputation of the island as an ecological tourism destination.
If the feasibility study is adopted by the community, a governance group of representative stakeholders would be formed to pursue the plan.
