The government has today unveiled plans to make New Zealand predator free by 2050, but acknowledged we don't yet have the science to get there.
The plan includes short-term goals, like wiping out possums or mustelids from at least one city within the next five years.
But scientists said the plan was noticeably shy on embracing things like gene editing technologies.
Conservation Minister Eugenie Sage said the achievement would not be cheap, but it would be worthwhile.
"It has been estimated to be in the billions, but it's not the cost it's the value of doing that.
"We have a very high proportion of our plants, birds, our reptiles and our insects that are only found here in Aotearoa, so we have an international responsibility to do this."
We want tech, but not gene tech
Lisa Ellis, a professor of philosophy and politics at Otago, described the goal as a moonshot.
Wiping out predators would require massive social change and harnessing all the technology we could, including gene editing, she said.
"I was really disappointed that they didn't initiate a conversation about potentially using gene editing technology. I think that conversation really ought to be starting now."
The plan stated New Zealand would need a "breakthrough science solution" by 2025 which could be used to cull one small mammal predator from the mainland.
Sage said she would like to see other options explored before turning to gene editing.
"It would require a public conversation and the public to say that [gene editing] is appropriate in New Zealand. We need to have that conversation in the future, perhaps."
"We have got a lot of existing tools and we're seeing new developments particularly with things like AI, trail camera, news lures, new toxins ... so I'm confident that we'll see new tools and technology developed before we need to consider anything like GE."
The poison 1080 continued to be "the most effective tool in the toolbox" for predator control, Sage said.
Ellis said while we did not know for sure that gene technology could get us there, it was probably one of the more humane ways to kill things.
"And a science oriented government of today is going to recognise that the gene editing technology today is very different to the scary GMOs of yore."
Manager of Predator Free 2050 Brent Beaven said New Zealand has shown it could conduct mass eradication, but the country needed to work on its defence.
"We've got bits of science, that's the whole point so it's not like we're starting from scratch. But the thing that's holding us back on the mainland is the ability to defend those sites so we don't get reinvasion."
Who pays?
The strategy did not include new money today - rather a set of goals and time points for measuring progress.
Sage said the plan would draw on funding of $81 million for pest control, announced in Budget 2018 and to be distributed over four years.
University of Auckland environment researcher Brendon Blue said killing predators was unlikely to be a high priority for "the substantial numbers of New Zealanders who are living below the poverty line".
"We would not expect tenants to plant an avocado tree hoping it will produce brunch in 10 years, so what makes us think they should be committed to predator control over the next 30?"
Asked if the government should subsidise traps, Beaven said that there may be a point in time where that may be looked at, but it wasn't on the cards immediately.
"Part of the joy of Predator Free 2050 is that it's a movement as much as a programme of work. The fact that people are spontaneously getting involved - I think you take something away form that if you fund that in government."
The plan to wipe out predators from New Zealand by the year 2050 was first announced in 2015, by then-prime minister John Key.