New Zealand's bid to rid itself of pest predators could hit a wall if worries from the public are ignored, finds a major report launched today.

The Predator Free 2050 effort aims to clear all rats, stoats and possums from the mainland by the middle of the century – and scientists have acknowledged that conventional measures alone won't be enough.

One recent scientific review found that saving our under-pressure nature couldn't be done without rolling operations out over wider areas, finding new and potentially controversial scientific solutions – and gaining public backing.

Now, another report authored by an expert panel has mapped out the social, ethical and cultural issues that will need to be tackled, finding that winning the war on pests was as much about people as it was technology.


Further, it found how failing to properly plan could result in lost conservation opportunities – and even preventable disasters.

"Biodiversity can mean different things to different people or groups," panel co-convenor Associate Professor James Russell said.

"Different people or groups can then be at odds about how to maintain biodiversity."

For example, he said, not all Kiwis wanted any certain introduced species gone – even when it hurt our native wildlife.

"One example is deer hunting – an important cultural and economic activity in many rural communities, despite the damage that deer cause in forested areas."

It highlighted that collective, national-scale action was needed – along with widespread social acceptance about what methods would be included.

"Traditional pest control technologies may need to either work in tandem with, or be replaced by, new technologies for eliminating the last survivors," Russell said.

"Social acceptance will depend on the specifics of these new technologies and will likely differ among groups.


"Some groups, for example, may prefer the use of novel technologies over the introduction of more effective toxins; others may take the opposite view."

Although the report didn't focus on what specific measures might be used, Russell said gene-editing was one currently in the public's mind.

Russell, a conservation biologist at the University of Auckland, expected that some people would likely always be opposed to this approach, even if the risk was shown to be minimal.

Conservation Minister Eugenie Sage has been criticised by National for sending Predator Free 2050 a letter in which she ruled out investing in research into genetically modified organisms and technologies.

But she recently clarified to the Herald that gene drives and other gene editing technologies needed to be better understood – and then accepted by the public – before they could be implemented.

"I think deep down every New Zealander wants to see our native biodiversity flourish," Associate Professor James Russell says. Photo / File

Russell further predicted there might be some resistance when people felt the pest-busting effort would impinge on their privacy or property rights.

"That's not to say they won't still support Predator Free New Zealand, but that appropriate models for working through such issues will need to continue to be applied, as they currently are for noxious weed management."

Ultimately, he said the 2050 goal would be critical to saving the country's native species.

Of the bird species that remained today, roughly one third were in serious trouble, with a further half in some trouble.

While Predator Free New Zealand targeted the eradication of selected mammal species, its fundamental aim was to restore native species and ecosystems – a goal with its own challenges.

"If the Predator Free New Zealand targets are met, removal of predation and competition from rats, stoats, and possums will not only impact native species, but could also affect other introduced species," he said.

"For example, mice might increase through competitor release, especially in mast seeding years in beech forests. It may also make cats a more prominent limiting factor for some native wildlife."

But he was optimistic the mission's barriers could be overcome.

"I think the scientific and conservation communities can easily work through all these issues by opening their doors to people from all walks of life: experts in social science and policy, local community leaders and tangata whenua," he said.

"I think deep down every New Zealander wants to see our native biodiversity flourish, and so it's actually quite easy to create opportunities for everyone to bring something to the table, as long as everyone remains open-minded to other views and leaves their politics at the door."

The report is being released at a two-day symposium at Te Papa, organised by the collaborative BioHeritage Challenge.