Three's a crowd in a two-man tent, especially when you're jackknifed around an assortment of packs and camera cases, a couple of car batteries, and a videophone. I gave up trying to sleep and watched the flimsy nylon walls heaving with each volley of rain.
Restless, I punched the on button of the video display—a playing-card-size screen on a domestic security phone pressed into service as a wildlife monitor—to see if there was any activity on the island summit 80 yards (73 meters) away. Nothing. Just a few scrubby bushes flailing in the wind.
I turned off the monitor, wormed my way back into my space between the two wildlife rangers with whom I was sharing this nighttime vigil, and listened to the cries of petrels careering overhead. Then, just before midnight, I heard a sound so deep and resonant it could have been coming from a Tibetan monastery. Ooooom . . . ooooom . . . ooooom. . . .
Three hands reached simultaneously for the video button. The screen flickered to life, and there, puffed up like a soccer ball, was a kakapo, New Zealand's ancient parrot of the night. He was standing in his bowl, a shallow depression he had made in the peaty soil, and booming his message to the four winds: "I am Lionel, male of males. Come to me, you females of Whenua Hou!"
It was a mesmerizing sound—so unlike a parrot, so unlike any bird, yet so in keeping with New Zealand's endemic menagerie of misfits and marvels, within which the kakapo ranks among the most misfitted and marvelous. This bird that thinks it's a bagpipe is the world's heaviest parrot and the world's only flightless parrot. And there are but 86 in existence. Most of them, including just 21 adult females on which the future of the species ultimately depends, live on this island: Whenua Hou, a wildlife sanctuary off the western coast of Stewart Island, smallest and southernmost of New Zealand's three main islands.
Once, the boom of the kakapo was part of the night music of all New Zealand. Each evening during the three-month summer courtship season males would gather in their ridgetop display grounds and sound off until dawn, a troupe of basso profundos trying to outdo one another in operatic fervor. Females attending these recitals bestowed their favors on the males whose performances pleased them most.
It is a matter of immeasurable sorrow to many of us who live in this country that the voice of the kakapo has been silenced throughout the mainland (the term we use for the North and South Islands, where most of New Zealand's 3.8 million people live). Its plangent chants have been replaced by the guttural hisses and shrieks of a plague of introduced Australian brushtail possums, marsupial leaf-eating machines that have supplanted the kakapo and other browsing birds from New Zealand's forests. The tracks to the kakapo display grounds are today traveled not by the sturdy feet of parrots but by the stealthy paws of their killers: rats, stoats, and feral cats—alien species that today have the run of the land.
Only on Whenua Hou and two other small predator-free islands can kakapos walk in peace—albeit with miniature radio transmitters attached to their backs and their every move monitored by human observers. When I visited Whenua Hou, staff of the Department of Conservation, the government agency charged with preserving the country's biodiversity, were preparing for what promised to be the best kakapo breeding season in 20 years. More than a hundred volunteers had been enlisted to take part in round-the-clock surveillance from tents like the one I was in. Their job would be to watch each nest on a video monitor, hurrying to check the eggs when the female left to forage, covering them with a mini-electric blanket if they became too cold, and radioing the island control center if anything went wrong.
There was an air of military efficiency about the place befitting the importance of the mission and the battle at hand. Like our national bird, the kiwi, kakapos embody the uniqueness and the plight of New Zealand's endemic biota. These birds are flagships of a threatened biological fleet. If we save them—or any of New Zealand's dozens of critically endangered species—we strike a blow for the cause of global ecological restoration. We remind ourselves and the world that the road to extinction is not a one-way street. And we preserve a bunch of truly outlandish creatures.
The surpassing strangeness of what we have in this country came home to me one night on Whenua Hou when I was helping weigh a three-year-old female kakapo called Aranga. (All kakapos have names, many of them suggested by New Zealand children. Aranga means "resurrection" in Maori.) The first surprise had been to find a flightless bird 30 feet (9 meters) up a tree. Evidently climbing is not a problem for kakapos, as Aranga demonstrated, using her beak as an ice ax and her toes as crampons to shinny down a supplejack vine to the ground.
As she nibbled the sweet potato I was using to coax her onto the scale, I felt the tickle of her whiskers and the warmth of her down. "Shall I cover you with a cloak of kakapo feathers?" a Maori saying asks of someone who complains of the cold. I leaned close, breathing the sweet fustiness of her plumage—an odor I once heard likened to the inside of a clarinet case.
When the food was gone and Aranga looked up with her inquisitive, owl-like face, I had to laugh. Look at you, I thought: An oversize budgie with an antique perfume that walks by night, lives not in the tropics but in the cold blast of the roaring forties, and breeds by holding a singing contest.
If kakapos seem bizarre, consider the four surviving species of kiwis, New Zealand's diminutive relatives of the ostrich. These flightless striders of the forest floor stretch the very definition of the word "bird." They have nostrils at the tips of their prodigious beaks (unlike any other bird), feathers that are shaggy, like hair, and an enormous egg that can be up to a fifth the weight of the bird that laid it. Their body temperature is closer to that of a mammal than a bird, and they are thought to scent-mark their territories, like dogs.
Kiwis and kakapos are far from the only avian oddities that have evolved in New Zealand, which is also home to the wrybill, the only bird in the world with a beak whose tip is skewed sideways (the better to probe for insects under stones in stream riffles); the kea, a mountain parrot that can rip open the back of a sheep or remove the window rubber from a parked car with equal facility; and the extinct huia, a lustrous blue-black beauty with tangerine head wattles and a bill for each sex—his stout and woodpeckerish, hers slender and downcurved.
Eccentricities abound among the invertebrates too. These islands have produced several tribes of wingless crickets called wetas, many of which possess profusely spined hind legs that they kick over their heads when threatened. Males of one weta species possess a mammoth pair of tusks for jousting.
There are land snails the size of hockey pucks, a spelunking spider that hangs its egg sac from the ceilings of limestone caves, and—the ultimate contradiction—a flightless fly. Among the more than 150 species of native earthworms—the largest of them four feet (1 meter) in length—is one which luminesces so strongly that a zoology professor is said to have once read a lecture by the light of a single worm.
How did this land become such a pageant of peculiarity? Two reasons, say evolutionary biologists: size and isolation. New Zealand is the largest oceanic archipelago on the planet and for its size the most distant from any major landmass. Large area and varied topography give scope for the processes of natural selection to produce diverse outcomes. Isolation fosters, preserves, and perpetuates the outcomes. The combination of these factors made New Zealand a hothouse of speciation, a laboratory where life experimented with what was possible and where the catchcry was "Vive la différence!"
The slice of land on which this genetic poker game took place sheared off from the remains of the ancient supercontinent Gondwana 80 million years ago and has been adrift ever since. During its long solitude it went through periods of submergence, when all that showed above the waves was a string of low, swampy islands, and through episodes of mountain building. It wandered between the tropics and the South Pole and endured tens of thousands of years in the deep freeze of glaciation.
Remarkably, many of the original players stayed at the table: the iguana-like tuatara, its slo-mo metabolism ticking away quietly while the land rose and fell around it; primitive earless frogs that lack webbing between their toes and can't croak; and the legendary moa—11 species ranging from a 40-pound mini-cassowary to the long-necked Dinornis giganteus, a quarter of a ton in weight and six feet (2 meters) high at the top of its back, possibly the tallest bird ever to walk the Earth.
The only newcomers were those that could fly or float their way across the oceanic barrier. Other than bats, no mammals succeeded in doing that, but dozens of birds did, including the ancestors of the kiwi and kakapo. Over the centuries many of these new arrivals, encountering no mammalian predators to harass them, went to ground. By the time humans arrived, a third of New Zealand's birds were either flightless or aerodynamically challenged.
Many species—vertebrate and invertebrate —became giants of their kind. Large herbivores process food more efficiently than small ones, and in the absence of other factors (such as the need to nimbly escape fast-moving predators) bigger is better. From weevils to waterfowl, species after species took this route, appropriating niches occupied elsewhere by mammals. In place of deer we had the moa; in place of cows, the takahe, a heavy grass-eating rail; in place of mice, the weta.
Cosseted by a benign climate and removed from the competitive cut and thrust of continental evolution, life in New Zealand slowed down. Species grew sedately, bred infrequently, and became Methuselahs of longevity.
It was too good to last. Around A.D. 1300 the spell was broken. Across the same ocean that had kept mammals at bay for 80 million years came a smooth-skinned supermammal in a canoe.
Although there is evidence that humans had visited at least a thousand years earlier, this time they came to settle, bringing rats, dogs, spears, and fire. The impact of the Polynesian colonists was immediate and catastrophic.
Within a hundred years the moas were gone. A few stragglers may have survived until the 1400s, but as viable species they were finished. Their demise became a byword for extinguished life. "Ka ngaro i te ngaro o te moa" run the words of a Maori lament. "Lost as the moa is lost."
Several other flightless birds joined moas in the cooking pits and shortly thereafter on the extinction list. Deprived of such prey, Haast's eagle, a raptor with a wingspan up to ten feet (3 meters) and talons the size of a tiger's claws—the largest eagle that has ever lived—went the same way.
Less than 500 years after Polynesians landed, Europeans followed in their wake, bringing a retinue of even more deadly predators along with tools and attitudes that accelerated the destruction of forests and fauna. Intent on creating the Britain of the South, they set about turning the country into a combination of farm and game park. As well as cattle and the sheep with which New Zealand would become synonymous, they successfully introduced ten species of deer, with moose thrown in for good measure in rainy Fiordland. Austrian chamois and Himalayan tahrs were let loose in the Southern Alps, where they grazed down a unique alpine flora that had never been subjected to the depredations of hoof and jaw. From our neighbor across the Tasman Sea, several species of wallabies were brought in, plus possums to create a fur trade. Rabbits and hares were introduced, then weasels, stoats, and ferrets to control them when their numbers exploded. That bungled attempt at biocontrol has cost us dearly: Mustelids, finding flightless and hole-nesting birds much easier to catch than rabbits, have become the most serious threat to what remain of our larger native birds.
Plant life fared little better. Over much of the country the native rain forest—a relict world of giant ferns, ancient cone-bearing trees, and thick moss carpets—was expunged, replaced with a hybrid flora epitomized by English oaks, American pines, and Australian eucalypts. The world has probably never seen such a comprehensive and rapid example of ecological colonization.
Richard Holdaway uses another word for it: blitzkrieg. Holdaway is a Christchurch paleoecologist who sieves bone fragments from caves and swamps and from the remnants tries to reconstruct the past. On a blistering day in Canterbury when the nor'wester was blowing hotter than a hair dryer, he took me to a vineyard to show me a lost world. We walked past neat rows of Pinot Noir to a gully that was once an old streambed. Holdaway pulled what looked like a broken pick handle out of a bank of debris and handed it to me. "Tibia of a stout-legged moa," he said. Then he lifted the cover off a pallet piled high with bones. "We have sufficient numbers of five different moa species to work out how common each one would have been in the population. For one species we have a whole age series from hatchling to adult. We've never had that before."
The deposit, which Holdaway likens to "finding Tutankhamun's tomb in your backyard," came within an ace of being destroyed before it was even recognized. "An earthmoving contractor was doing some drainage work on the site last year," said Holdaway. "One of the owners dropped by to check on progress and noticed bones sticking out of a pile of spoil. She stopped the digger and called the local museum, and the museum called me. The first two bones we found after I got here were a moa cranium and an eagle radius. I knew then we were on to something special."
Carbon-14 dating gives an age of 2,000 years at the bottom of the deposit and 800 years at the top—a snapshot of life immediately before Polynesian settlement. As well as the moa and the giant Haast's eagle (which, Holdaway informed me, could hit its prey with the force of a 35-pound concrete block dropped from an eight-story building), the site has yielded tuataras, the extinct eastern kiwi, kakapos, an extinct giant harrier, ducks, pigeons, quails, wekas (flightless rails), parakeets, snipes, and water hens, "along with tree stumps, millions of seeds, and vast numbers of land snails. Basically we have everything here but the birds singing."
These birds—even the extant ones—haven't sung in Canterbury in a long time, though this area once had the greatest biodiversity in the country. "Look around," Holdaway said. "Tell me if you can see a single native species." I scanned the rolling farmland with its windbreaks of poplar and pine, its introduced pasture grasses and grazing sheep. A European skylark trilled.
"Maybe if you looked hard enough you might find a native caddis fly in the stream down there," he continued, "but otherwise this is an alien landscape." The pitch of his voice rose a notch. "Politicians and tourism promoters talk about 'clean, green New Zealand' as if this country were an ecological paradise. Sure, by world standards it's clean, and much of the time it's green, but it isn't New Zealand." He pointed to the bone pile. "There's the real New Zealand. I stand among its ruins every day of my working life."
Ruined, but not obliterated. There are still places where the old order endures, but you have to go high into the mountains or to offshore islands. You have to go where the predators haven't.
I found a living piece of the lost world 70 miles (113 kilometers) south of Stewart Island. There, rearing out of the Southern Ocean like a clutch of granite icebergs, lie the Snares, one of New Zealand's five subantarctic island groups. Among the least modified terrestrial ecosystems on Earth, they are also a place with their own set of oddities—penguins that roost in trees and sea lions that snooze in forest glades. Although these specks of land are little more than a square mile in area, as many seabirds are said to nest here as in the whole of the British Isles.
That statistic is not so startling when you consider New Zealand's geographic situation: a 1,200-mile strip of land encompassed by ocean. This country is the world center of seabird biodiversity. Eighty-four species—nearly a quarter of the seabirds of the world—breed in New Zealand, 36 of them endemic to these shores. With a similar land area, the British Isles has 24 seabird species and no endemics.
On the Snares the commonest seabird is the titi, or sooty shearwater. Titis are impressive fliers, migrating from their breeding islands in the Southern Hemisphere to subarctic waters between Japan and Alaska and back again each year—in the case of the Snares birds a round-trip of some 15,000 miles (24,140 kilometers). They are also accomplished divers, hunting small fish to depths of 130 feet (40 meters). Adult titis will travel 1,100 miles (1,770 kilometers) to a productive feeding area. Chick-rearing parents, which alternate between foraging and nest minding, spend as many as 11 days at sea each trip.
But their navigational prowess is their most astonishing trait. A titi returning to the Snares must first find the islands, then figure out which part of the uniformly gray-green forest of tree daisies contains its burrow, then crash-land through the canopy, avoiding the hundreds of neck-snapping V-shaped slots created by branches pointing skyward like booby traps. Then the bird must correctly locate the entrance to its burrow in order to receive an enthusiastic welcome from its mate and not the angrily snapping bill of a stranger.
To get the full impact of a couple of million birds coming in from sea and announcing "Honey, I'm home," I decided to spend a night in the open, on top of their underground condominiums.
The ground was cooing under my feet as I set out in the early evening, picking my way across the springy crust of peat that forms the forest floor. I walked like a person crossing a frozen pond, testing my weight with each step—and with good reason, for all that covers the subterranean city of seabird burrows is a thin mat of soil and tree roots. A misjudged step can send you crashing through on top of some unsuspecting bird. Once or twice that happened, and I had to kneel down and perform a hasty reroofing job, using twigs as rafters and broad tree-daisy leaves as tarpaulins. Patting down a new peat layer on top, I would set off again, sidestepping sleeping sea lions and pausing to watch the ceaseless traffic of penguins padding like hobbits along forest trails.
I found a flattish area between burrow entrances and unrolled my sleeping bag. There was hardly a twig or leaf on the soil. All detritus is dragged below ground and used as nesting material. I propped a stout cudgel nearby, in case a sea lion should blunder into my campsite, and started taking notes.
10.15 p.m. It's nearly dark, and all around me titi are crashing through the branches and thudding to the ground. Amazingly, they don't seem to hurt themselves. They get straight up and walk to their burrows. What a racket, though! They sound like a cuckoo speeded up and put through a distortion filter: Ah-hoo, ah-hoo! Ah-haa, ah-haa! Ah-hee, ah-hee!
11.05 p.m. I'm shining a torch on a bird that is only a foot away from me. It has bright black eyes and a slender grey beak. The plumage is many shades of charcoal, grey and black. I can reach out and stroke its feathers.
Midnight. The noise is dying down at last. A few diving petrels are coming in, with the same swoosh-crash-thud approach. One lands beside my head. It is tiny, and has blue legs and feet.
3.55 a.m. The birds are preparing to take flight again and look for food, so for the past hour the noise has been building up and now it's deafening. The pairs must be saying their goodbyes. They are moving towards the take-off areas, walking right over my sleeping bag. I'm going to follow them.
4.15 a.m. It's just light enough to see. The birds are streaming from all directions to their ramps and launching spots. There's a lot of jostling in the queues. It's like rush-hour on the freeway. Some birds flap their wings rapidly to warm up their flight muscles. If they don't get a good takeoff they run across the water, flapping like crazy until they get enough lift.
By dawn the forest was empty, the soil as bare and smooth as if the cleaners had been in. Unless you had seen it, you would have no inkling of what had taken place during the night.
Island sanctuaries such as the Snares—some naturally free of introduced predators, some cleared of intruders by strenuous human effort—have been the salvation of New Zealand's endemic flora and fauna. Three hundred and thirty islands of ten acres (4 hectares) or more dot the coastline, along with countless smaller islets and rock stacks. The Department of Conservation manages 220 of them as reserves.
Recently predator-control techniques have reached a level of effectiveness that allows areas of the mainland to be managed as ecological islands—a concept that was beyond the dreams of biologists even two decades ago.
One such island lies within mountainous Te Urewera National Park, 821 square miles (1,321 square kilometers) of native forest near the eastern fin of the fish-shaped North Island. A three-square-mile peninsula jutting into Lake Waikaremoana has been protected by rat and stoat traps set across its base, and these catch most predators. For the past ten years biologist John McLennan has been establishing and studying kiwis there.
I joined him as he tracked Chick 52 down the side of a cliff, across a stream, and into thick fernery and scrub beside the lakeshore. With his radio telemetry aerial held aloft, he looked like an errant TV repairman seeking better reception. The pips on the receiver grew louder, and I knew we were closing in on the six-week-old kiwi. Laying down his equipment, McLennan reached into a clump of toetoe, a native grass, and withdrew a furry, pear-shaped bird the size of a hamster, with two very big feet.
Taping its scaly ankles together—carefully avoiding the aspirin-size radio transmitter attached to one of them—McLennan hoisted the kiwi on a spring balance and read the weight: a shade over 20 ounces.
"Forty days to go before it's safe," he said, passing the bird to me to hold. Kiwis need to reach one and three-quarter pounds before they can be considered off the stoat menu. With the birds putting on weight at a rate of a fifth of an ounce a day, that's a long and worrying adolescence.
But so far the scheme seems to be working. McLennan has between 50 and 60 kiwis on the peninsula now, and in the last breeding season he lost hardly any chicks to predators.
For McLennan and his co-workers, one of the most satisfying aspects of the project has been the support they have received from the nearby predominantly Maori community. Locals have helped build a fenced enclosure where the kiwis can be relocated should a plague of stoats somehow breach the defenses, and schoolchildren have started worm farms to help feed the kiwis and have donated hens' eggs to bait the stoat traps (stoats can't resist eggs).
At one community meeting McLennan described the kind of restored ecosystem he envisaged the peninsula supporting in years to come. At the end of the meeting a Maori kuia—an elder—came up to him and said, "Yes, that's how I remember it when I was a girl."
"I think that was when it hit me that we really can turn the clock back in this country," McLennan told me. "We have the technology. It's just a dollar issue, and that comes down to personal commitment and political will."
Looking at the shaggy bundle cradled in my arms, wiggling its little vestigial wing stumps and giving an occasional snap with its tweezer-like bill, I felt like saying, "Where do I sign?"
Children in New Zealand grow up learning two bird stories. One involves a wren, a cat, and a lighthouse keeper, and it happened over a century ago on Stephens Island, at the northern tip of the South Island. The wren was one of only four flightless songbirds in the world (two of the others were also New Zealand wrens). The cat caught several of the little brown birds and brought them to the lighthouse keeper's house. The keeper, whose name was Lyall, sent them to local and overseas museums to be identified. By the time the wren had been named, the cat had stopped catching them. There were no more to be caught. Lyall's wren was extinct.
The other story involves a robin, a wildlife officer, and a brewery. In 1979 the Chatham Island black robin had dwindled to a population of just five birds, of which only one female, named Old Blue, was a viable breeder. Wildlife officer Don Merton, a pioneer of threatened species work, devised a daring strategy to save the bird. As a child Merton had fostered gold-finch nestlings to his grandmother's canary. He tried a similar trick on the Chatham Islands, giving Old Blue's eggs to tomtits (another type of robin) to incubate. It worked. The tomtits accepted the eggs, and Old Blue kept renesting and producing more.
The really remarkable thing was that Old Blue was nine years old when she started breeding, and black robins normally don't live beyond the age of five or six. When she died at age 13, having produced 11 chicks, her death was announced in the New Zealand Parliament. Old Blue had saved her species.
And the brewery? Chatham Islanders, tough farming and fishing people and not the sort you'd expect to fall in love with an endangered bird, adopted the black robin as a mascot. They named their local beer—along with a shipping company and a rugby team—after the bird.
Robins and wrens. Conservation in New Zealand will continue to be a mixture of the two with, we hope, victories edging out defeats in the ecological battle. Who knows, one day even kakapos may return to some of their former haunts, finding new homes on mainland islands. I like to think so—to imagine some child of the future wakening in the night to the sound of distant booming, the heartbeat of an ancient time.
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