The late Sir Paul Callaghan’s call to arms on pest eradication has struck a chord with New Zealanders concerned by the multiple threats to this country’s indigenous wildlife. As reported by Rebecca Priestley in last week’s Listener, in the last lecture Callaghan delivered he exhorted his audience to embrace a “crazy” idea: to take the model used to clear offshore islands of introduced pests, and transfer it to the mainland on a larger scale than existing successful sanctuaries like Maungatautari in Waikato, and Zealandia in Wellington.
Starting by eradicating the pests in specific areas, then controlling them in concentric zones around those cleared areas, Callaghan envisaged a dozen 100,000ha restoration zones. Then he went further. He had a “mad” idea, he said, and suggested that all exotic pests that were threatening New Zealand’s forests, birds and wildlife could be exterminated, starting from Stewart Island “and we work our way up”.
A few years ago, the Stewart Island Rakiura Community and Environmental Trust secured funding from the Tindall Foundation to research the feasibility of ridding the 174,600ha island of rats, possums and feral cats in the hope that it might become a “Galapagos of the South”. The study found it would be technically possible, though not without considerable expense, disruption and the prospect of community disagreement on the project’s wisdom and feasibility. Some years on, there are no definite plans to attempt pest eradication on such a scale.
Callaghan’s inspiring, visionary and audacious idea of ridding the entire country of pests, allowing natural plants and wildlife to flourish, is worthy of his name and one that New Zealanders should embrace wholeheartedly but for a single, crucial flaw: it will not work. Perhaps one day it might, but not yet. The resources, technology, commitment and public buy-in are not available at present to make the plan achievable.
For every statistic that lifts the spirits of conservationists, there is another that dashes them. As the Parliamentary Commissioner for the Environment, Jan Wright, pointed out in her study on 1080, about 30% of New Zealand is reserved in the public conservation estate. That is an admirable achievement, but on the downside, only an eighth of that land has any pest control at all – and it is pests that pose the single greatest threat to the survival of many bird species.
The eminent conservationist Professor Charles Daugherty heard Callaghan’s “Zealandia” lecture more than once. Thirty years ago, Daugherty says, no one would have dared to dream that such a vision would be uttered. But not long before that, the idea of even clearing an offshore island of rats was also derided as unachievable. Now, those islands have made the difference between species being saved and being lost forever.
For every success, though, there are regular setbacks. Twenty-four bird species including the famous Chatham Island black robin, dragged back from the furthest edge of extinction when just one female remained, are on DoC’s list of species critically threatened with extinction. A further 15 species are endangered and 38 species vulnerable.
Callaghan’s view was that other countries that New Zealanders admired and visited had their great attractions – usually an historic built or cultural environment – and New Zealand’s equivalent was its unique natural habitats and species. Although many of those species are endangered, threatened and hard to reach, they are still indisputably with us in a way that has long been lost in most of Europe.
As Daugherty points out, we know what New Zealand looked like only a relatively short time ago. Like other countries, New Zealand has taonga on display in museums and art galleries, but our richest and most diverse heritage is outside, in native forests and other habitats, sometimes on farms but more often in national parks and reserves, on predator-free off-shore islands and in mainland sanctuaries. It is that which makes this country unique.
The conservation battle is everyone’s to wage. With leadership from entities like DoC, Forest & Bird and scientists, and input from as many volunteers as can be rallied to the cause, and as much private and public funding as can be raised, Callaghan’s vision can be kept alive. To do so is not only our privilege, but our duty.