The reasons for this are in one sense complicated—the result of a peculiar set of geological and historical accidents—and in another quite simple. In New Zealand anything with fur and beady little eyes is an invader, brought to the country by people—either Maori or European settlers. The invaders are eating their way through the native fauna, producing what is, even in an age of generalized extinction, a major crisis. So dire has the situation become that schoolchildren are regularly enlisted as little exterminators. (A recent blog post aimed at hardening hearts against cute little fuzzy things ran under the headline “Mrs. Tiggy-Winkle, Serial Killer.”)
Not long ago New Zealand’s most prominent scientist issued an emotional appeal to his countrymen to wipe out all mammalian predators, a project that would entail eliminating hundreds of millions, maybe billions, of marsupials, mustelids, and rodents. To pursue this goal—perhaps visionary, perhaps quixotic—a new conservation group was formed this past fall. The logo of the group, Predator Free New Zealand, shows a kiwi with a surprised expression standing on the body of a dead rat.
New Zealand can be thought of as a country or as an archipelago or as a small continent. It consists of two major islands—the North Island and the South Island, which together are often referred to as the mainland—and hundreds of minor ones. It’s a long way from anywhere, and it’s been that way for a very long while. The last time New Zealand was within swimming distance of another large landmass was not long after it broke free from Australia, 80 million years ago. The two countries are now separated by the 1,200-mile-wide Tasman Sea. New Zealand is separated from Antarctica by more than 1,500 miles and from South America by 5,000 miles of the Pacific.
As the author David Quammen has observed, “Isolation is the flywheel of evolution.” In New Zealand the wheel has spun in both directions. The country is home to several lineages that seem impossibly outdated. Its frogs, for example, never developed eardrums but, as if in compensation, possess an extra vertebra. Unlike frogs elsewhere, which absorb the impact of a jump with their front legs, New Zealand frogs, when they hop, come down in a sort of belly flop. (As a recent scientific paper put it, this “saltational” pattern shows that “frogs evolved jumping before they perfected landing.”) Another “Lost World” holdover is the tuatara, a creature that looks like a lizard but is in fact the sole survivor of an entirely separate order—the Rhynchocephalia—which thrived in the early Mesozoic. The order was thought to have vanished with the dinosaurs, and the discovery that a single species had somehow managed to persist has been described as just as surprising to scientists as the capture of a live Tyrannosaurus rex would have been.
At the same time New Zealand has produced some of nature’s most outlandish innovations. Except for a few species of bats, the country has no native mammals. Why this is the case is unclear, but it seems to have given other groups more room to experiment. Weta, which resemble giant crickets, are some of the largest insects in the world; they scurry around eating seeds and smaller invertebrates, playing the part that mice do almost everywhere else. Powelliphanta are snails that seem to think they’re wrens; each year they lay a clutch of hard-shelled eggs. Powelliphanta too are unusually big—the largest measure more than three and a half inches across—and in contrast to most other snails, they’re carnivores and hunt down earthworms, which they slurp up like spaghetti.
New Zealand’s iconic kiwi is such an odd bird that it is sometimes referred to as an honorary mammal. When it was first described to English naturalists, in 1813, they thought it was a hoax. Kiwi are covered in long, shaggy feathers that look like hair, and their extended, tapered beaks have nostrils on the end. They are around the size of chickens but lay eggs that are 10 times as large, and it usually falls to the male, Horton-like, to hatch them.
New Zealand’s biggest oddballs were the moa, which, in a feathers-for-fur sort of way, stood in for elephants and giraffes. The largest of them, the South Island giant moa, weighed 500 pounds, and with its neck outstretched could reach a height of 12 feet. Moa fed on New Zealand’s native plants, which, since there were no mammalian browsers, developed a novel set of defenses. For instance, some New Zealand plants have thin, tough leaves when they are young, but when they mature—and grow taller than a moa could chomp on—they put out leaves that are wider and less leathery. The Australian naturalist Tim Flannery has described New Zealand’s avian-dominated landscape as a “completely different experiment in evolution.” It shows, he has written, “what the world might have looked like if mammals as well as dinosaurs had become extinct 65 million years ago, leaving the birds to inherit the globe.” Jared Diamond once described the country’s native fauna as the nearest we’re likely to come to “life on another planet.”
With about half the population of New Jersey, New Zealand is the sort of place where everyone seems to know everyone else. One day, without quite understanding how the connection had been made for me, I found myself in a helicopter with Nick Smith, who was then the country’s minister for conservation.
Smith, who is 49, has a ruddy face and straw-colored hair. He is a member of the country’s center-right National Party and calls himself a “Bluegreen.” (Blue is the National Party’s color.) He got interested in politics back in the 1970s, when, as an exchange student in Delaware, he met Joe Biden. We set off from Smith’s district office, in the city of Nelson, on the northern tip of the South Island, and drove out to the helicopter pad in his electric car.
“When the first settlers came here, they tried to create another England,” Smith told me. “We were Little Britain. The comment about us was, we were more British than the British. And as part of the maturing of New Zealand, there’s the question, What do you connect your nationhood to? You know, for America it’s very much the flag, the Constitution, those sorts of things. The connection with species that are unique to New Zealand is increasingly part of our national identity. It’s what we are as New Zealanders, and I make no bones of the fact that the government is keen to encourage that. You need some things for a country to hold together.”
He went on, “I say to people, If you want your grandkids to see kiwi only in sanctuaries, well, that’s where we’re headed. And that’s why we need to use pretty aggressive tools to try to turn this around.”
My visit happened to coincide with the application of one of these aggressive tools. The country’s Department of Conservation was conducting a massive aerial drop of a toxin known as 1080. (The key ingredient in 1080, sodium fluoroacetate, interferes with energy production on a cellular level, inflicting what amounts to a heart attack.) New Zealand, which has roughly one tenth of 1 percent of the world’s land, uses 80 percent of its 1080. This year’s drop—the department was planning to spread 1080 over nearly two million acres—had been prompted by an unusually warm winter, which had produced an exceptionally large supply of beech seed, which in turn had produced an explosion in the number of rats and stoats. When the beech seed ran out, the huge cohort of predators was expected to turn its attention to the native fauna. Smith had approved the 1080 operation, which had been dubbed Battle for Our Birds, but the timing of it troubled him; owing to the exigencies of rat biology, the drop had to take place right around the time of a national election.
“If you ask the cynical politics of it, people don’t like poisons but they like rats even less,” he told me. “And so I’ve been doing a few quite deliberate photo opportunities with buckets of rats.”
On this particular day, Smith was attending a more cheerful sort of photo op—one with live animals. When we arrived at the helicopter pad, three other people were already there, all associated with a privately funded effort to restore one of the country’s most popular national parks, named for Abel Tasman. (In 1642, Tasman, a Dutch explorer, was the first European to reach New Zealand—though he didn’t quite reach it, as four of his sailors were killed by Maori before they could land.) Smith and I got into the helicopter next to the pilot, the other three climbed into the back, and we took o
ff. We flew over Tasman Bay and then over the park, which was studded with ghostly white trees.
“We like to see all those dead trees,” Devon McLean, the director of the restoration project, announced cheerfully into his headset. He explained that the trees were invasive pines, known in New Zealand as “wilding conifers.” I had a brief vision of scrawny seedlings rampaging through the forest. Each dead tree, McLean said, had been individually sprayed with herbicide. He was also happy to report that the park had recently been doused with 1080.
After about half an hour we landed on a small island named Adele, where we were greeted by a large sign: HAVE YOU CHECKED FOR RATS, MICE AND SEEDS? A few years ago, after an intensive campaign of poisoning and trapping, Adele was declared “pest-free.” The arrival of a single pregnant rat could undo all that work; hence the hortatory signage. In another helicopter the conservation department was going to deliver two or three dozen representatives of one of New Zealand’s rarest species, the South Island saddleback. The birds would be released onto Adele, where, it was hoped, in the absence of rats, they would multiply.
More people began to arrive by boat—reporters, representatives of several regional conservation groups, members of the local Maori iwi, or tribe. By this point it was drizzling, but there was a festive mood on the beach, as if everyone were waiting for a celebrity. “Hardly any New Zealanders have ever seen a saddleback,” a woman whispered to me.
In anticipation of the birds’ appearance, speeches were offered in Maori and English. “It has taken us Pakeha New Zealanders a little while to gain an appreciation of what is special here and to really be committed to its protection and survival,” Smith said, using the Maori word for “European.” “It’s kind of scary to think of South Island saddlebacks—there are only about six hundred that exist on the planet.”
Finally the birds arrived, in a helicopter that had been loaned for the occasion by a wealthy businessman. Three crates were unloaded onto the beach, and Smith and a pair of local dignitaries were given the honor of opening them. South Island saddlebacks are glossy black, with patches of rust-colored feathers around their middles and little orange wattles that make them look as though they’re smiling. They are another example of an ancient lineage that persists in New Zealand, and they have no close relatives anywhere else in the world. The birds hopped out of their crates, flew into the bush, and were gone.
There are two quick ways to tell a Norway rat from a ship rat. One is to look at the ears. Ship rats have large ears that stick out from their heads; Norway rats’ ears are shorter and less fleshy. The other is to look at their tails. Again, Norway rats’ are shorter. With a ship rat, if you take its tail and fold it over its body—here it obviously helps if the rat is dead—it will extend beyond its nose.
These and many other facts about rats I learned from James Russell, an ecologist at the University of Auckland. Russell’s office is filled with vials containing rat body parts in various stages of decomposition, and he also keeps a couple of dead rats at home in his freezer. Wherever he goes, Russell asks people to send him the tails of rats that they have trapped, and often they oblige. Russell then has the rats’ DNA sequenced. Eventually he hopes to be able to tell how all of New Zealand’s rat populations are related.
“I would be inclined to say rats are our biggest problem,” Russell told me. “But I have colleagues who spend their career on stoats, and colleagues who spend their career on cats. And they open all their talks with ‘Stoats are the biggest problem’ or ‘Cats are the biggest problem.’”
Russell, who is 35, is a slight man with tousled brown hair and a cheerful, let’s-get-on-with-it manner which I eventually came to see as very New Zealand. I ended up spending a lot of time with him, because he volunteered to guide me along some of the country’s windier back roads.
“New Zealand was the last large landmass on earth to be colonized,” he told me one day as we zipped along through the midsection of the North Island. “And so what we saw was the tragedy of human history playing out over a short amount of time. We’re only ten years behind a lot of these things; that’s as compared to countries where you’re hundreds or thousands of years behind the catastrophe.”
New Zealand’s original settlers were the Maori, Polynesians who came around the year 1300, probably from somewhere near the Society Islands. By that point people had already been living in Australia for some 50,000 years. They’d been in continental North America for at least 10,000 years, and in Hawaii, which is even more remote than New Zealand, for more than 500 years. In each case, it’s now known, the arrival of humans precipitated a wave of extinctions; it’s just that, as Russell points out, these “tragedies” were not recorded by the people who produced them.
When the Maori showed up, there were nine species of moa in New Zealand, and it was also home to the world’s largest eagle—the Haast’s eagle—which preyed on them. Within a century or two the Maori had hunted down all of the moa, and the Haast’s eagle too was gone. A Maori saying, “Ka ngaro i te ngaro a te moa,” translates as “Lost like the moa is lost.”
In their ships the Maori also brought with them Pacific rats, or kiore. These were New Zealand’s first introduced mammals (unless you count the people who brought them). The Maori intended to eat the kiore, but the rats multiplied and spread far faster than they could be consumed, along the way feasting on weta, young tuatara, and the eggs of ground-nesting birds. In what in evolutionary terms amounted to no time at all, several species of New Zealand’s native ducks, a couple of flightless rails, and two species of flightless geese were gone.
The arrival of British settlers, in the middle of the 19th century, brought in more—many more—new invaders. Some of them, like the Norway rat and the ship rat, were stowaways. Others were introduced deliberately, in an effort to make New Zealand feel more like home. The “importation of those animals and birds, not native to New Zealand,” an 1861 act of the colonial parliament declared, would both “contribute to the pleasure and profit of the inhabitants” and help maintain “associations with the Old Country.” What were known as “acclimatization societies” sprang up in every region. Among the many creatures the societies tried to “acclimatize” were red deer, fallow deer, white-tailed deer, sika deer, tahr, chamois, moose, elk, hedgehogs, wallabies, turkeys, pheasants, partridges, quail, mallards, house sparrows, blackbirds, brown trout, Atlantic salmon, herring, whitefish, and carp. Brushtail possums were specially imported from Australia, in an attempt to start a fur industry.
Not all the new arrivals took; others took all too well. By the perverse logic of such affairs, some of the most disastrous introductions were made in an effort to control previous disastrous introductions. Within a few decades of their importation, European rabbits had overrun the countryside, and in 1876 an act was passed to “provide for the Destruction of Rabbits in New Zealand.” The act had no perceptible impact, so stoats and ferrets were released into the bush in the hope that they would be more effective.
“Our forebears tried most experiments that could possibly be conceived and some that would be difficult for anyone with any knowledge of ecology to seriously contemplate,” Robert McDowall, a New Zealand naturalist, has written in a history of introduction efforts. The combined effect of all these “experiments,” particularly the introduction of predators, like stoats, has been ongoing devastation. Roughly a quarter of New Zealand’s native bird species are now extinct, and many of those which remain are just barely hanging on. If current trends continue, it is predicted that within a generation or two the land of Kiwis will be without kiwi.
“The defence of isolation for remote islands has no fallback position,” John McLennan, a New Zealand ecologist, has written. “It is all or nothing, akin to virginity, with no intermediate state.”
Sirocco, a sexually dysfunctional kakapo, normally lives alone on his own private island. On occasion, though, he is brought, with great fanfare, to the mainland, and this is where James Russell and I set out to meet h
im, at a special mountaintop reserve ringed by a 29-mile fence. The fence is 7 feet high and made of steel mesh with openings so narrow an adult can’t stick a pinkie through. At the base of the fence, an 18-inch apron prevents rats from tunneling under; on top, an outwardly curved metal lip stops possums and feral cats from clambering over. To get inside, human visitors have to pass through two sets of gates, an arrangement that made me think of a maximum-security prison turned inside out.
Kakapo—the name comes from the Maori, meaning “parrot of the night”—are nocturnal, so all audiences with Sirocco take place after dark. Russell and I joined a group of about 20 other visitors, who had paid $40 apiece to get a peek at the bird. Sirocco was hopping around in a dimly lit plate-glass enclosure. He was large—about the size of an osprey—with bright green-and-brown feathers and a bulbous, vaguely comical beak. He gazed through the glass at us and gave a sharp cry.
“He’s very intense, isn’t he?” the woman next to me said.
Alone among parrots, kakapo are flightless, and alone among flightless birds, they’re what’s known as lek breeders. During mating season a male will hollow out a little amphitheater for himself, puff up his chest, and let out a “boom” that sounds like a foghorn. Kakapo, which can live to 80, breed only irregularly, in years when their favorite foods are in good supply.
Kakapo once were everywhere in New Zealand. In the late 19th century they were still plentiful in rugged areas; Charlie Douglas, an explorer who climbed some of the steepest mountains of the South Island, described them standing “in dozens round the camp, screeching and yelling like a lot of demons.” But then their numbers crashed. By the 1970s there was just one small population remaining, and it was threatened by feral cats. In the 1980s every individual that could be caught was captured and “translocated.” Today there are 126 kakapo left, and all of them, save Sirocco, live on three remote, predator-free islands: Little Barrier, Codfish, and Anchor.
The Best American Science and Nature Writing 2015 Page 22