Ensuring fewer stragglers are left behind is a current priority, Bramley says. To this end, ZIP is working with Christchurch-based entrepreneur and engineer Grant Ryan to trial “smart” cameras that can detect and home in on particular species. Andrew Kralicek, who heads the Molecular Sensing Team at the New Zealand Institute for Plant & Food Research, is attacking the problem a different way. He’s developing inexpensive biosensors that can pick up the unique chemical compounds produced by a specific species’ urine or feces. “You’ll be picking up a particular biomolecule that your pest releases—like a fingerprint,” Kralicek explains. When the device senses one of these compounds, it will trigger an electrical signal, which is sent via satellite to a computer to pinpoint a rogue predator. Such specific location information could soon aid the ZIP team in targeting aerial applications of 1080 to finish off the few remaining predators in an area, and to prevent reinvasion once it has been cleared. “A year ago, we would not have been able to tell you we’ve got an aerial technique for eradicating possums,” Bramley says. “Now we’re very close to having that technique.”

The biggest technological breakthrough, Russell and other predator eradication visionaries believe, will come in genetics. Tweaking a gene so that females produce only males, for example, could winnow down the females enough to eventually eliminate a population. At this stage, scientists in New Zealand and Australia are developing a possum gene map to pinpoint potential target genes on which to make such a tweak, called gene drive. The technology graduated from fruit flies to a proof-of-concept for mice earlier this year, but it’s still a huge leap from mice to possums or stoats, neither of which have ever been genetically modified. In terms of the technology alone, “it’s probably five years away,” Russell says.

That lag time could be a good thing, though, because this kind of unproven, novel technology must be vetted carefully, says Neil Gemmell, a geneticist at the University of Otago in New Zealand. As gene drive technology has advanced, he has become increasingly concerned that a predator programmed to die out in New Zealand could spread.

If rats and stoats and possums got into New Zealand, they can also get out, he notes. And these species aren’t exotic invasive species everywhere; they have home ranges and niches in local ecosystems that could suffer if self-destructing individuals arrive and spread. “If you’d asked me a year ago, or maybe even six months ago, I would have told you gene drives are great, and they’re probably the best way to control pests in New Zealand,” says Gemmell, who co-authored a paper on the subject due out in the journal PLOS Biology in November. “Now I’d say, gene drives are great, but we need to figure out how to turn them off and how to regulate them.” Otherwise the impacts—both positive and negative—could reach far beyond New Zealand’s borders.

In addition to pushing scientific boundaries and spurring debate among scientists, these genetic manipulations also are likely to test the public’s tolerance. So far, New Zealanders have been largely supportive of traditional eradication efforts. Many people have traps in their own backyards. “There’s this huge growth in support for the work,” Bramley says. In Wellington, he notes, a public survey found that only 1 percent of respondents opposed the rat eradication on a nearby peninsula. But as the technological advances become increasingly high-tech—and in some people’s minds sci-fi—securing public support may prove more complex. “We would never act on this without having absolute social license,” says Barry, the former conservation minister. “And I acknowledge we don’t have it currently. We need to bring the public with us throughout the process.”

To that end, Russell and social scientist Emily Parke, also at the University of Auckland, have convened a bioethics panel whose members include an ecologist, a psychologist, a philosopher, a wildlife manager, and a Maori leader. The panel is drafting a report that will lay out ways to involve the public early and often as things like gene drive are developed. To assess what the public knows about new predator control technologies and how they feel about them, Edy McDonald, who leads the social science team at the Department of Conservation, recently conducted a public survey. Preliminary results released in November show that of the 8,000 New Zealanders who responded to the survey, only 14 percent thought enough pest control was being done. But the use of gene drives and other new technologies to address the problem received mixed reviews. “We really want to have the conversation with the country, so that bumpers can be put in the road if there are any concerns about any of the technologies that come up,” she says.