New Zealand is one of the most biologically unusual places on earth. For approximately 85 million years it was isolated from other landmasses — long enough for its plant and animal life to evolve along paths found nowhere else. The result is extraordinary: tuatara, a living fossil from the age of dinosaurs. Kākāpō, a flightless nocturnal parrot that can live for a century. Kiwi, birds that lay the largest egg relative to body size of any bird on earth and navigate by smell. Wētā, giant insects that fill ecological roles elsewhere played by small mammals. Carnivorous land snails. Native bats that are the country's only indigenous land mammals.
This biological heritage is remarkable and fragile — and a significant proportion of it is in danger of being lost within the lifetimes of people alive today.
New Zealand has one of the worst extinction records of any country in the world. Around 4,000 of its indigenous species are currently threatened or at risk of extinction. Conservation work — by the government, by communities, by iwi, and by countless volunteers — represents a sustained national effort to prevent that loss and, where possible, to restore what has been damaged.
Why New Zealand's Biodiversity Is So Vulnerable
Understanding conservation in New Zealand requires understanding what makes its biodiversity so exceptionally threatened.
New Zealand's long isolation produced species that evolved with no mammalian predators. Birds evolved to be flightless because there was no evolutionary pressure to fly away. They nested on the ground because there was no reason not to. They lost the instincts that enable birds elsewhere to escape predators — backing away, hiding, fleeing. When humans arrived and brought rats, possums, stoats, ferrets, cats, and other mammals, they encountered a fauna completely without defences against them.
The result was catastrophic. Māori settlement — beginning around 1280 CE — and the predators, fires, and hunting that accompanied it drove approximately fifty species of birds to extinction, including the moa, the giant flightless birds that once grazed New Zealand's forests. European settlement and the deliberate and accidental introduction of many more mammalian predators accelerated the devastation.
Introduced predators remain the primary threat to native species today. Rats eat eggs, chicks, and adult birds. Stoats prey on nesting birds and raid burrows. Possums — brought from Australia for the fur trade — browse native plants and destroy the forest structure that native species depend on. Feral cats are highly effective hunters of native birds. Ferrets, weasels, and hedgehogs add to the pressure.
Beyond predators, habitat loss through land clearance, freshwater degradation, disease — particularly kauri dieback caused by the pathogen Phytophthora agathifera — and increasingly climate change all threaten native ecosystems.
The Scale of the Problem
The numbers are sobering. Around 4,000 indigenous species are currently threatened or at risk of extinction in New Zealand. Of these, around 550 are classified as Nationally Critical — the highest-risk category, meaning they face an immediate high risk of extinction.
This includes some of the country's most iconic species. Kākāpō — the world's only flightless parrot — has 235 individuals alive today, all known, all named, all wild. Takahē — a large flightless rail believed to be extinct until rediscovered in a remote Fiordland valley in 1948 — exists in small and carefully managed populations. The kea — the world's only alpine parrot — faces multiple pressures from predators, disease, lead poisoning from old roofing materials, and human interference.
The freshwater fish of New Zealand are among the most threatened in the country. Almost all species of galaxiid — the scaleless native fish that fill freshwater habitats — are threatened or at risk, many critically. Black stilts, kākāriki parakeets, rock wrens, kiwi of multiple subspecies, New Zealand sea lions, Hector's and Māui dolphins — the list of species fighting for survival is long and urgent.
The Department of Conservation
Conservation in New Zealand is primarily the responsibility of the Department of Conservation — Te Papa Atawhai — the government agency established in 1987 to manage public conservation land and protect native biodiversity.
DOC manages approximately 8 million hectares of public conservation land — about 30 percent of New Zealand's total land area — including national parks, scenic reserves, nature reserves, and stewardship land. It is responsible for protecting the ecosystems and species on that land, for managing the infrastructure that enables people to access and experience it, and for coordinating conservation efforts more broadly.
DOC's core conservation work includes predator control, threatened species management, biosecurity, weed and pest management, ecological restoration, and community and volunteer engagement.
The agency's budget has been a persistent concern. Conservation advocates have long argued that DOC is chronically underfunded relative to the scale of the challenge. The gap between the areas where predator control is needed and the areas where it can actually be resourced and delivered reflects this constraint. Approximately 1.8 million hectares — roughly 20 percent of public conservation land — currently receives sustained predator control. The remaining 80 percent does not.
Predator Control: The Core Tool
Controlling introduced mammalian predators is the single most important conservation intervention in New Zealand. Without predator control, many of the country's most threatened species cannot survive or breed successfully.
Predator control operates at multiple scales and through multiple methods.
Aerial 1080 1080 — sodium fluoroacetate — is the primary tool for large-scale predator control over difficult, rugged terrain. Applied aerially in bait form, 1080 is highly effective at killing rats, possums, and stoats across large areas that could never be reached by ground-based methods. It degrades rapidly in the environment and is present naturally in many native plants — one reason New Zealand's native wildlife is generally more tolerant of it than introduced species.
1080 remains controversial. Some people object to the use of any poison, others raise concerns about non-target species, and others distrust a substance they associate with risk. DOC maintains that 1080 is the best tool currently available for landscape-scale predator control and that the alternative — leaving introduced predators unchecked — causes far more harm to native wildlife than the carefully managed operations.
The 2026 beech mast — the largest South Island beech mast in seven years — has driven an expanded predator control programme. Beech masts produce vast quantities of seeds that temporarily feed enormous populations of rats and stoats, which then devastate native wildlife populations when the seeds are gone. DOC's response is to conduct predator control in two rounds — before seeding to keep predator numbers low when the surge occurs, and after the seed is gone to catch any remaining predators.
Ground-based trapping and bait stations An extensive national network of volunteer and professionally maintained trapping and bait stations operates across the country — in forests, in farmland, in suburbs. Community groups, landowners, and volunteers contribute millions of trap checks annually, supplementing the work DOC can do with its own resources. The national trapping effort is one of the largest citizen science and volunteer conservation programmes in the world.
Fenced sanctuaries Predator-proof fences enclose areas of suitable habitat from which all mammalian predators have been removed, creating mainland islands where native species can live and breed without predator pressure. Zealandia in Wellington, Sanctuary Mountain Maungatautari in Waikato, and numerous others across the country provide refuges where species that cannot survive on the open mainland can establish populations. Kākāpō were released at Maungatautari in 2023 — a significant milestone in their recovery.
Island sanctuaries New Zealand has cleared introduced predators from over 100 offshore islands — an achievement that represents decades of sustained effort and significant technical innovation. These predator-free islands are lifeboats for the most vulnerable species. Whenua Hou (Codfish Island) off Stewart Island is home to a significant portion of the kākāpō population. Tiritiri Matangi Island in the Hauraki Gulf has been transformed from degraded farmland to a thriving native ecosystem that visitors can explore.
Predator Free 2050
In 2016 the New Zealand government announced Predator Free 2050 — the most ambitious conservation goal in the country's history. The target: to eradicate rats, stoats, possums, and mustelids from all of mainland New Zealand by 2050.
This would be unprecedented. No country has ever eradicated invasive mammalian predators across a landmass the size of New Zealand. The tools to do so do not yet exist. Aerial 1080 can suppress predator populations but cannot achieve the complete eradication required. New bait technologies, gene drives, and other innovations are under development, but none is ready for deployment at scale.
Predator Free 2050 is being pursued on multiple tracks simultaneously. Large landscape-scale projects — covering hundreds of thousands of hectares — are demonstrating what is achievable at scale and providing research platforms for testing new approaches. Breakthrough research through multiple agencies is working to develop the technologies needed for complete eradication. Community projects across the country are expanding the network of trapping and control.
Predator Free 2050 Ltd — the company set up to invest in large landscape-scale projects and breakthrough research — was disestablished in August 2025, with its work absorbed into DOC. The ambition remains but the institutional structure has changed.
Species Recovery: The Hardest Cases
For the most critically threatened species, intensive management — often involving individual care of every surviving animal — is the only thing standing between them and extinction.
Kākāpō — with only 235 individuals, every bird matters. The Kākāpō Recovery Programme monitors every individual, manages their breeding through supplementary feeding and nest management, incubates eggs artificially when necessary, and tracks every chick. The programme is a collaboration between DOC, Ngāi Tahu — who regard kākāpō as a taonga species — and multiple partners including Meridian Energy. The population has grown from fewer than 50 in the 1990s to 235 today — a genuine conservation success, though the species remains critically endangered.
Takahē — declared extinct in 1898 and rediscovered in the Murchison Mountains in 1948. DOC manages a carefully maintained population distributed between managed sites including Burwood Bush, Sanctuary Mountain Maungatautari, and several predator-free islands. A project to establish a self-sustaining wild population in the Southern Lakes has been underway with growing success.
Kiwi — five species of kiwi survive in New Zealand, all threatened. Intensive management including Operation Nest Egg — where eggs are removed from the wild, hatched in captivity, and released when chicks are large enough to survive predators — has produced tens of thousands of birds. Community kiwi sanctuaries and intensive predator control around kiwi populations are essential to their survival.
The Role of Iwi and Mātauranga Māori
For Māori, conservation is not a modern concept imported from environmental science. It is woven into how Māori have always related to the natural world.
Kaitiakitanga — guardianship of the natural world — is a core concept in tikanga Māori. Iwi and hapū hold kaitiaki relationships with specific species, places, and ecosystems. Many native species are taonga — treasured possessions — to particular iwi, with deep cultural significance that goes far beyond ecological value.
Iwi are now active participants in conservation at every level — from strategic direction of national programmes to on-the-ground management of their own rohe. Te Tira Whakamātaki is a Māori environmental organisation supporting indigenous people and solutions in conservation. Ngāi Tahu are partners in the kākāpō recovery programme, in major island restoration projects, and in the AF8 earthquake preparedness programme. The incorporation of mātauranga Māori — traditional knowledge — into conservation science is increasingly recognised as essential, not optional.
The Island Restoration Ambition
New Zealand is partnering with international conservation organisations in an ambitious programme to restore some of its largest offshore islands. In 2025, DOC and partners joined the Island-Ocean Connection Challenge — a global initiative to restore 40 island-ocean ecosystems by 2030.
New Zealand's three projects under this programme are:
Maukahuka — Auckland Island — the largest subantarctic island in New Zealand, home to extraordinary biodiversity including four albatross species and over 100 endemic species. Invasive mice, pigs, and feral cats threaten this ecosystem. A project estimated to cost $78 million is planned to eradicate these species.
The Chatham Islands — home to critically endangered species including the black robin, once reduced to five individuals before being brought back through intensive management, and numerous endemic species. Eradication of invasive mammals would create conditions for far more species to thrive.
Rakiura — Stewart Island — New Zealand's third largest island, 90 percent public conservation land. Plans are underway to eradicate feral cats, rats, possums, and hedgehogs, with the vision of returning kākāpō to the island.
Together these represent some of the most ambitious island restoration projects ever attempted anywhere in the world.
Community Conservation: The Volunteer Army
Conservation in New Zealand is not only government work. It is a national project involving hundreds of thousands of volunteers, community groups, schools, landowners, and businesses.
Trap networks maintained by community groups cover large areas of suburban and rural New Zealand. Restoration planting projects involve thousands of participants. Wetland restoration, weed control, predator monitoring, and species surveys are carried out by communities who have taken ownership of the natural environments around them.
This community engagement reflects something genuine about New Zealand culture — a sense that the native wildlife and landscapes are a shared inheritance worth fighting for. It is also essential: DOC cannot do what needs to be done without the volunteer and community sector supplementing its efforts.
The Biosecurity Connection
Conservation and biosecurity are inseparable. Preventing new invasive species from entering New Zealand is as important as managing those already here. The Ministry for Primary Industries operates New Zealand's biosecurity system at the border — inspecting passengers, cargo, and mail for potential threats.
Kauri dieback — the disease caused by Phytophthora agathifera that kills kauri trees, the ancient giants of the northern North Island — has no cure and spreads through contaminated soil on boots and equipment. Management relies on hygiene protocols at kauri forest entrances, track closures, and public education. The full scale of the threat to New Zealand's kauri is still being understood.
New pathogens, new weeds, and potentially new predators could arrive at any time. The biosecurity system is the first line of defence — and like all first lines of defence, it is imperfect.
Where Things Are Heading
The trajectory of New Zealand's conservation effort is one of genuine progress against an enormous challenge that is not getting smaller.
Genuine conservation successes exist — species have been saved from the brink, populations have recovered, islands have been restored, and the kōkako has been reclassified from Threatened to At Risk: Recovering. These achievements reflect real effort by real people over decades and should be celebrated.
But the overall picture — 4,000 threatened species, 80 percent of public conservation land without sustained predator control, freshwater ecosystems in decline, climate change altering habitat conditions — is one where the scale of what remains to be done vastly exceeds the resources currently applied to it.
Predator Free 2050 is the most ambitious conservation goal New Zealand has ever set. Achieving it requires technical breakthroughs that do not yet exist, sustained political commitment across multiple governments, and investment at a scale that has not yet been committed. Whether New Zealand achieves it will depend on whether the scientific, political, and community will can be sustained over a quarter century.
Quick Q&A
Why is New Zealand's native biodiversity so unique and so threatened? New Zealand's 85 million years of isolation produced species found nowhere else on earth that evolved with no mammalian predators. When humans arrived with rats, possums, stoats, cats, and other mammals, native species had no defences against them. The resulting extinctions and ongoing predation pressure make New Zealand one of the countries with the worst extinction records in the world.
What is 1080 and why is it used? 1080 — sodium fluoroacetate — is a poison used aerially to control rats, possums, and stoats across large areas of difficult terrain. It is the most effective tool currently available for landscape-scale predator control. It degrades rapidly in the environment. It is controversial but widely supported by conservation scientists as essential to native species survival.
What is Predator Free 2050? A government goal announced in 2016 to eradicate rats, possums, stoats, and mustelids from all of New Zealand by 2050. The goal is unprecedented in scale and will require new technologies to achieve. Predator Free 2050 Ltd, the company set up to pursue it, was disestablished in 2025 with its work absorbed into DOC.
How many kākāpō are alive? 235, all wild, all individually known and named, living on predator-free islands in Fiordland and off Stewart Island, and at Sanctuary Mountain Maungatautari.
What is kaitiakitanga? Kaitiakitanga is a Māori concept of guardianship over the natural world — the responsibility of tangata whenua to care for the ecosystems, species, and taonga of their rohe. It is now embedded in New Zealand conservation practice and law as a principle that must be respected in how the natural world is managed.
Key Takeaway
New Zealand has the most unusual and most threatened native biodiversity of any developed country in the world — the product of millions of years of isolation followed by centuries of human impact. Conservation work — by DOC, by iwi, by communities, and by thousands of volunteers — is genuine, significant, and producing real results. But the scale of the challenge — 4,000 threatened species, continent-wide predator pressure, freshwater decline, and climate change — requires sustained ambition and investment beyond what has so far been committed. Understanding how conservation works in New Zealand means understanding both the extraordinary achievements that are possible when people commit to the work, and the enormous distance still to travel.
Keep Exploring
NZ's Building Blocks → What 1080 is and how it works → What Predator Free 2050 aims to do → What kaitiakitanga means in conservation → What the Department of Conservation does → What kauri dieback is and why it threatens northern forests
NZ: How It Works → How Land Use Works in New Zealand → How Water Shapes New Zealand → How Climate Change Affects New Zealand → How Natural Hazards Shape New Zealand → How Te Tiriti Shapes Modern New Zealand
Sources
Department of Conservation — National Predator Control Programme Operations 2026
Department of Conservation — Managing Our Biodiversity
Department of Conservation — Kākāpō Recovery
Department of Conservation — Three Prime New Zealand Islands Join Global Restoration Campaign, February 2025
Department of Conservation — Ecological Restoration of Offshore Islands
Predator Free NZ Trust — About Predator Free 2050
WWF New Zealand — Endangered Species Aotearoa
LEARNZ — Threatened Species
Earth Sciences New Zealand — Natural Hazards and Risks
DOC — Action for Nature: Implementing New Zealand's Biodiversity Strategy 2025-2030