Nearly a decade since the ambitious Predator Free 2050 goal was launched, what progress has been made?

“There are three stages when you open a trap,” says David, who works in pest control in Fiordland. “There’s the fresh stage: you open it up and find a limp fluffy corpse, that’s all good. In the second stage, the bodies get gooey and gross, then they dry out and turn to skin and bones. The second stage is the worst stage.”

Working as a trapper, which David has done since his graphic designing job ended 18 months ago, is intense. “Your schedule is determined by this unpredictable, transient thing: the weather,” David says. The commute is very different to most office jobs. “You go from a loud, sociable helicopter to utter silence in the middle of nowhere, just you and the traps. It’s an immediate whiplash.” 

David is used to the rhythm of this work now. The sound of water moving downhill. Tired muscles from following a trapline through dense forest. The mechanical motion of opening a trap. “You’re looking for ‘is there anything different in this box’?” Many are empty, and might just need fresh bait. Others have dead pests in them: for David in Fiordland, that’s mostly rats, with the odd stoat. In other areas of the country, it’s possums filling the traps, or other mustelids like weasels. 

In long, lonely days, checking trap after trap, David has time to think. “Trapping is physically intensive, and not super cheap…. Are there smarter ways of doing this? Could there be a way to achieve everything we’ve done in the last 10 years more quickly?” he asks. 

It’s been nine years since New Zealand set its Predator Free 2050 goal, to eradicate the most damaging introduced predators from the country by the midway point of the 21st century, and now, a million hectares of land have some degree of trapping, aerial control, or other protection (ie predator-proof fences). Targeting rats, stoats and possums has been incredibly successful, and it bodes well for New Zealand’s vulnerable bird and reptile species. But to keep that land protected, the trapping and aerial toxins must continue, while further money and technology is required for removing predators from the rest of the country. 

Where the money comes from

The $28 million of initial funding from the government when the goal was announced went towards creating Predator Free New Zealand Limited, a joint venture company set up to identify “large, high-value predator control projects” and attract co-investors. The intention was that each dollar of funding from the government would be accompanied by two dollars from both local government and the private sector. There would be economic incentive to take action: predators don’t just eat native birds and native bush, but cost the economy an estimated $3.3bn each year (according to 2016 government figures.)

Nine years later, more than $300m of public money has gone towards pursuing the PF2050 goal. There’s a patchwork of different organisations involved: DOC is the lead agency and carries out extensive trapping and aerial toxins alongside its other responsibilities, while Crown Research Institutes Manaaki Whenua and Scion are researching new technologies to use against pests. On the private side, a company called ZIP (Zero Invasive Predators) is responsible for removing pests from large areas of Westland and developing new technology, while the whole farming industry sponsors possum culling (through OSPRI, and also supported by MPI) to reduce the impact of bovine TB. A whio project near Gisborne, meanwhile, is selling biodiversity credits and iwi have also carried out extensive pest control on their land. 

There’s a fine line, though, between “patchwork” and “patchy”. With a succession of different CEOs and board members, Predator Free 2050 Limited has been criticised for alleged governance and management issues, including not being able to tell the government how many jobs it had created with Jobs for Nature funding. The funding also isn’t stable: funding for predator control has come from Jobs for Nature (a Covid economic response) and the Provincial Growth Fund. The PGF money ended in June 2024, while remaining Jobs for Nature funding can be used until June 2026. With the government’s 2025 budget, due to be announced on May 22, set to be tighter than ever, there aren’t great hopes for a big investment. Uncertain funding means that DOC, too, has received charitable donations for non-PF3050 work on the subantarctic islands. Another funding shift could happen if bovine tuberculosis is eliminated, meaning farmers would no longer have an obvious incentive to sponsor possum control.

If there isn’t ongoing funding, the gains made in predator control could be lost. “The minute we stop [controlling pest species], it goes back to what it was – we’re in a loop, we can’t get out,” describes James Ross, an ecologist who has dedicated his life to studying how to control invasive predators. To “defend” predator-suppressed land from reinvasion, workers like David have to be regularly dispatched into some of Aotearoa’s most remote and gnarly terrain to check for pests that might or might not be there.

Possums, mustelids and rats are voracious, adaptable eaters who are comfortable in a range of habitats, which is why they’ve adapted to Aotearoa so successfully. Their intelligence and resourcefulness means that complete eradication is much more expensive than initial removal. Landcare Research estimates that killing 95% of pest species costs about $20-$30 per hectare, while killing 100% of a pest species costs about $400 per hectare. 

A key part of PF2050’s success so far hasn’t just been charitable donations, but committed volunteers. “You only need one in three people trapping around Zealandia to control predators, I’m always amazed how many people volunteer to do things,” says Ross. Volunteer work has been key to projects like Predator Free Miramar and Capital Kiwi, with pest numbers low enough for the national bird to be safe in the hills around Wellington. Ross is inspired by programmes like Living Springs which get hundreds of primary school-aged children involved in pest control in Christchurch. It’s harder, though, to get volunteers to some of the remote areas where possums and stoats also run rampant, when predator control isn’t a question of a few traps in the backyard or nearby bush, but of two days tramping up steep hills in the rain. 

The technological frontier 

The necessity of keeping pest-suppressed areas thriving while trying to increase the amount of land without invasive predators is a difficult balance. Ross puts it bluntly: “We’re either stuck doing sustained control over 50% of New Zealand for ever, or we can develop better technology to defend New Zealand from rats.”

David is mostly using old-fashioned tunnel traps. He has to scoop the dregs of unused bait out with his hands and replace it with his hands. “Fundamentally, we’ve been stuck in the same place for a long time – using the same toxins, and trapping hasn’t fundamentally changed in the last hundred years,” says Brent Beaven, DOC’s Predator Free 2050 programme manager. Dropping toxins like 1080 over big swathes of land by helicopter is faster than getting hundreds of workers and volunteers following the directions of various organisations to follow track lines through the bush – so is there a better way?

Beaven estimates that about 50% of Predator Free funding (it’s hard to get an exact estimate, because of the funding being split between DOC and so many other entities) goes to developing new technologies. “It’s that metaphor – you have to keep the patient alive while you’re building the hospital. Predator Free is building the new hospital.” 

One promising development is remotely connected cameras. Beaven says it’s “bloody hard” to be completely sure an area is predator free. But detection is important, because the last rodents/mustelids/possums left in an area will necessarily be the most wily, having avoided poison and traps for the longest. Cameras on Ulva Island, a predator-free sanctuary just off the coast of Rakiura, recently had a rat incursion. Although there was just one dead rat in a trap, cameras showed that there were other rats on the island. “The rats were picked up really early – traps were refreshed, localised bait stations were set up – it’s an example of how rapidly we can respond,” Beaven says. ZIP also uses thermal cameras throughout its South Westland project, which is attempting to eliminate possums, rats and stoats from 100,000 hectares of the West Coast. 

Traps that set themselves, powered by a gas canister, are also an option. The AT220 trap can reset itself up to a hundred times, and can be connected for remote monitoring, identifying the species it kills and sending an alert to the person who monitors it. For people working on removing pests from Kaitōrete Spit around Lakes Ellesmere in Banks Peninsula, for example, it’s much more efficient to check a computer feed alerting them to overnight kills than to drive and walk along to check dozens of traps. That said, there’s a cost to this technology: the AT220 costs $550 and the most advanced model with AI detection for target species costs $1,030. DOC also uses Goodnature self-resetting traps powered by gas canisters, which cost around $150 each (but presumably cheaper in bulk). By comparison, a tunnel trap – essentially some bits of wood hammered together with a trap inside – is $34.50 from the Predator Free Trust, and many community groups give them away for free. 

Further away is the concept of genetic editing to change the predators’ gene drive, or to develop toxins that only target particular genes in target species, making them completely safe for all others. Genomic mapping of targeted invasive species is under way. 

As well as science advancements, increasing the scale of predator-controlled areas will have a positive effect. “ZIP is trialling a buffer and core method in South Westland,” Beaven explains. The area is bracketed by the Southern Alps (without ice axes or helicopters, the possums and rats are stuck on one side) and the Tasman Sea, meaning only two sides of the area need to be defended. Intensive trapping and monitoring around the borders means that pests, which can only go so far in a night, don’t get to the core area. “That’s a much more cost-effective way to hold the line,” Beaven says. The bigger the contiguous area of pest-suppressed or eliminated land, the bigger the area that can be totally pest free, as the edges require the most resources to protect. 

“That could work in parts of Fiordland – there’s so much isolated water,” David says. It’s a strategy that needs to go with the remote cameras for the easiest possible detection.

Is Predator Free 2050 worth shooting for? 

“This is the most ambitious conservation project attempted anywhere in the world, but we believe if we all work together as a country we can achieve it,” said then prime minister John Key when he launched Predator Free 2050 in 2016. In 2025, it still seems ambitious, if it’s possible at all. Headway has been made towards the interim 2025 progress goals: the million hectares of New Zealand mainland with suppressed predators, which has essentially been achieved. Other 2025 goals are out of reach, like eradicating possums or mustelids from at least one New Zealand city (although the pest-free Miramar Peninsula effort is going well), and eliminating all mammal predators from uninhabited offshore islands.

Beaven is reluctant to commit to exact timelines for where the programme will go next, nearly 10 years after it was first announced.  “By 2030, we want to have enough technology to prove that we can roll out [the programme] to the rest of the country, in a variety of habitats.” If that technology is scalable, results could be fast. “If there’s resourcing to enable it, between 2030 to 2050 there could be a rollout of a million hectares [with invasive pests eliminated] a year.”

It’s clear that, as trapper David says, predator eradication “will not be a cheap exercise”. But while it’s important to tally the costs of various predator-free programmes, it’s not like kākāpō or whio can repay the tens of millions of dollars spent on their survival by going on to become upstanding contributors to the economy. Instead, the success of Predator Free is an invitation to think about the value of biodiversity more holistically. 

“In most places, it’s loss of habitat that causes extinctions. In New Zealand, it’s predators,” says Ross. “We could take the foot off [Predator Free] and we would lose a lot of species…. It all comes down to our willingness to pay to keep biodiversity.” When there aren’t toothy mammals eating them, their eggs or their habitat, Aotearoa’s native species thrive: there are now so many once perilously endangered kākāpō that Beaven says there won’t be room for them all after another breeding season on (pest-free) Codfish Island/Whenua Hou. 

Biodiversity is important in a non-monetisable way; Beaven notes that even though most New Zealanders won’t see a kiwi in the wild, it’s still the name they’ll use to identify themselves. There’s a silver fern, another native species, representing one of our greatest sports teams. “Our wildlife is tied to our identity as a country – even if people never see a kākāpō, the concept that those wild places exist is important.”

To people on the ground, like David, trudging through the chilly forests of Fiordland no matter the weather, it’s hard to tell how much impact the predator-free effort is having. Some months, he finds “rats galore”. At other times, he finds very few, especially in summer when there are lots of other sources of food. But he also notices lots of bird song and flourishing native trees and plants, a sign that not everything is being eaten. A good sign.  

“If the takahē died tomorrow, humanity would be fine,” David says. “But I think –  isn’t it good for humanity to do something not just in our own self-interest?”