A scientist has worked out how much it would cost to make New Zealand entirely free of introduced pests – $24.6 billion or about 12 per cent of gross domestic product.
Helpfully, Dr James Russell, a quantitative ecologist in the University of Auckland's schools of biological sciences and of statistics, suggests it might be easier to stagger his proposed programme over a decade.
Writing in the university's Uninews, he said there was a general consensus that New Zealand could be free of introduced mammalian predators in 50 years.
He suggests Great Barrier and Stewart islands could be the first to be made predator-free.
The North and South islands could be cleaned up through grassroots organisations.
"These groups would create predator-free arks, and over time increase their halo influence by expandng the scope of their programmes," he says.
"Predator-free fenced sanctuaries and peninsulas benefiting from barriers such as rivers or even motorways and cities, would emerge across the country."
He says Auckland was an obvious example and noted that possums made it into Northland only in the last 50 years.
There would be a "rolling front" of pest removal across the landscape.
Given the cost involved, Russell says it would require the endorsement of the overwhelming majority of the country.
"We would be creating a new core value for our country, which would need to be held as strongly as, say, those in the United States hold the constitution – and its purpose would need to be defended."
New Zealanders already had conservation values but a "predator-free New Zealand would be an opportunity to flaunt it on the international stage".
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