海角大神

New Zealanders are deeply connected听to their land, and the menagerie of peculiar critters that have evolved on the nation's hundreds of islands. But in recent years, Kiwis, as residents call themselves, have watched with dismay as their country has become听ground zero of Earth鈥檚 extinction crisis. With fierce determination, however, they have also become the听tip of the spear in fighting it.

Home to one of the highest proportions of threatened species in the world,听New Zealand's wildlife is in a state of crisis. The听first global analysis of established alien species, published Monday, ranked New Zealand, along with Hawaii and Indonesia, as one of the globe's three hotspot regions for invasive species. With nearly a third of the country鈥檚 endemic species at risk, including its talismanic kiwi bird,听the nation has taken on a seemingly insurmountable challenge: total elimination of three invasive predators from its two main islands by the year 2050.听The endeavor has earned the moniker 鈥淣ew Zealand鈥檚 Apollo program.鈥�

Non-native predators are听some of the biggest threats to New Zealand wildlife. Scientists estimate that invasive stoats, rats, and possums kill 25 million native birds in the country every year. That threat looms large for New Zealanders, who view nature as 鈥渁lmost like our church,鈥� says Nicola Toki, Threatened Species Ambassador for the New Zealand Department of Conservation (DOC).

鈥淥ur nature is who we are, and we can鈥檛 describe ourselves as Kiwis to the rest of the world if we don鈥檛 have any left,鈥� she says.

The country is already a world leader in invasive species management, but an eradication on the scale of the Predator-Free New Zealand 2050 (PFNZ) initiative would be unprecedented. The science to achieve it doesn鈥檛 exist yet, and it would likely unearth social and logistical challenges that invasive species managers have never seen or even contemplated before.

Yet the potential benefits, for New Zealand and the entire planet, could be immense. The planet is currently experiencing what many scientists believe to be the sixth mass extinction event in the past 500 million years, with about a quarter of all the planet鈥檚 known species on track to go extinct by 2050. If PFNZ is successful, experts say, it could unlock new techniques and technologies to prevent tens of thousands of species around the world from being wiped out.

And if anyone can achieve it, the Kiwis can, says Daniel Simberloff, an ecologist at the University of Tennessee, Knoxville and an expert in invasive species.

鈥淥f all the nations in the world, they have been certainly the most aggressive in dealing with this problem,鈥� he adds, especially on New Zealand鈥檚 smaller islands. 鈥淏ut the idea of eradicating introduced predators from [the main islands], that鈥檚 a quantum leap.鈥�

The world is watching

The rest of the world is eagerly watching New Zealand and the PFNZ initiative.

Simply perfecting eradications on uninhabited islands 鈥� which New Zealand is already close to doing 鈥� would alone have a huge impact on global conservation, says Heath Packard, the director of communications at Island Conservation, a Santa Cruz, Calif.-based nonprofit dedicated to preventing extinctions by removing invasive species from islands around the world.

Island Conservation is currently struggling with its own challenges of carrying out an eradication on an inhabited island. The organization has been working for seven years to plan and fundraise for a rat eradication on Floreana Island in the Gal谩pagos.

鈥淲e are continually reaching more complex projects,鈥� Mr. Packard adds. 鈥淭he ambitious vision that New Zealand has could be a major stepping stone for us to be considering places that are much bigger and grander in scale.鈥�

Forty percent of endangered species worldwide live on, or rely听on,听islands, and invasive species are the leading cause of extinctions on islands. Since 1500, 80 percent of all recorded extinctions have been on islands.

But听Floreana illustrates the scale of New Zealand鈥檚 challenge 鈥� and its potential benefits. The island is only 67听square miles, with a permanent population of 140 people, and Island Conservation鈥檚 eradication project would likely cost at least $7 million.听New Zealand鈥檚 largest offshore island, Rakiura Island, by comparison, is 10 times as large, with almost three times as many people.

鈥淭he prospect of what New Zealand is trying to achieve鈥� lends hope, says Packard, that听鈥渢here may be tools and techniques in place to consider reversing the extinction trajectory in a place like Hawaii,鈥� which is听home to about听a quarter of all endangered species听in the United States.

How small mammals became such a big problem听

For about 80 million uninterrupted years, native wildlife evolved on the islands of New Zealand without the threat of ground-based predators. The Maori didn鈥檛 settle the islands until about 1350, while European explorers didn鈥檛 arrive until 1769.听With the arrival of humans, other invasive mammals weren鈥檛 far behind.

And for animals that evolved to only look to the sky for threats, the results have been predictably devastating.

For native wildlife, the 鈥渂est thing to do in face of avian predators is to be camouflaged and to freeze,鈥� says the DOC鈥檚 Dr. Toki. 鈥淚f you camouflage and freeze and a ferret鈥檚 chasing you, you don鈥檛 stand chance because those things use smell.鈥�

Rats arrived in the late 1700s, while New Zealanders brought possums in the 1830s to establish a fur trade that still exists today. Stoats were introduced in the 1880s to help control rabbits and hares. Since the mid-1800s there have been 20 bird extinctions in the country.听

New Zealanders began to take invasive predators seriously in the 1970s, and the country since has become the world鈥檚 leading expert on the issue. Invasive predators have been eradicated on 117 of the country鈥檚 offshore islands, and the country develops traps and bait systems used around the world. That success has been replicated globally, with about 1,000 offshore islands now cleared of invasive predators.听

鈥淲e鈥檙e good at killing small furry animals,鈥� says Toki. 鈥淚f you look at any pest eradication program around the world, it will generally have a Kiwi scientist running it or a Kiwi helicopter pilot [helping] it.鈥澨�

The most stubborn invasive species听

Eradicating invasive predators from small uninhabited islands is one thing, but Phil Cowan 鈥� an ecologist at Landcare Research, a government-funded research organization 鈥� laughs off the suggestion that PFNZ will involve simply scaling up that approach.

鈥淎lmost all the eradications of pests from islands, both in New Zealand and globally, have been done on uninhabited islands,鈥� he says, 鈥渟o trying to do operations like this in areas where people are living is going to require a whole lot of discussion with people who live in these areas to work out what will be acceptable and what will not.鈥澨�

Ironically, the species in New Zealand that conservationists there expect to be toughest to deal with isn鈥檛 rats, possums, or stoats 鈥� but humans. And for conservationists around the world, how the New Zealand public is convinced to not only support the predator-free goal, but to actively participate as well, may be the most valuable lesson to come out of the enterprise.听

Developing the technology needed to kill the tens of millions of predatory mammals in the country will be difficult, but it will be a matter of when, not if, experts say. Social acceptance and participation, they say, is a much more complex challenge.听

There are simple, traditional concerns, such as the use of toxins. But there are knottier problems as well. The possum fur trade is reportedly worth听$130 million a year, with some trappers pulling in six figures annually.听Some Kiwis worry that revitalizing native species could create new ecological and social problems. Others aren鈥檛 enamored with the idea that more native wildlife could mean more tourism.

Rakiura Island (or Stewart Island) is a living example of some of the challenges mainland New Zealand may have to contend with in the coming decades.

The island 鈥� a few miles off the southern coast of New Zealand鈥檚 Southern Island 鈥� is mostly a national park, but it has one town with a permanent population of 400 people, one school, one general store, and one 15-mile road that connects it all. The DOC and the Morgan Foundation, a philanthropic organization, have been funding a predator-free effort there for several years, but some of the locals 鈥� particularly those who enjoy the harsh, sub-Antarctic seclusion of the island 鈥� have expressed reservations.听

鈥淭raditionally we鈥檝e been a fishing community, so the move to tourism is not always welcomed by people,鈥� says Sandy King, who has lived in the town, Oban, for 50 years. 鈥淭here are lots of strange faces around. They fill up the shop.鈥�

Some residents oppose the construction of predator-proof fencing because they would feel 鈥渓ike they鈥檙e being fenced in,鈥� Ms. King says. Others are worried about the use of toxins or the possibility of reinvasions if eradication is successful.

Wild ambassadors

The most powerful ambassadors in the quest to bring a wary public along with the idea may not be conservationists, but the animals they are trying to save.听There may be no better example of this than Wellington, New Zealand's capital.

In 1999 a 556-acre听ecosanctuary, surrounded by a 5.3-mile predator-proof fence, opened on the edge of the Wellington city suburbs. Eighteen species of native wildlife have been reintroduced into the Zealandia sanctuary, six of which have been absent from the New Zealand mainland for more than a century. A large native parrot called the K膩k膩, for example, has grown from a population of six to more than 800.

But as impressive as Zealandia has been in reviving endangered native species, perhaps even more impressive is the effect it鈥檚 been having on Wellingtonians.

As species, particularly birds like the K膩k膩, have regenerated inside the sanctuary, they鈥檝e journeyed outside the fence into the city itself, leading to a 鈥減roximity鈥� or 鈥渉alo鈥� effect. As more people physically see the animals, they become more interested in protecting them, including through helping eradicate invasive predators.

Geoff Simmons, who lives a 20-minute drive from Zealandia, has witnessed this firsthand.

鈥淭wenty years ago people would have known the Tui听as a native bird, and that would have been about it,鈥� says Mr. Simmons, an economist at the Morgan Foundation. 鈥淣ow people talk about K膩k膩, Saddleback, Hihi. All these birds they never knew existed are appearing in their back yards, and once people have something they don鈥檛 want to lose it.鈥�