Rat Island

by William Stolzenburg

  In 2010 Macquarie’s managers went back to finish the job, bombing the rabbits and rodents with brodifacoum. Horrible weather intervened, the eradication failed, and more than four hundred birds were found inadvertently poisoned—the latter embarrassment again making the headlines.

  Undeterred, the eradicators march on. Island Conservation’s Karl Campbell—of Galápagos goat-killing fame—and his partner-in-mischief Josh Donlan have been flirting with heretofore unthinkable leaps to those islands once called continents. Campbell and Donlan—who four years ago directed a battle discharging half a million rounds of ammo and killing 160,000 goats on a Galápagos island the size of San Francisco—have recently been visiting with the governments of Chile and Argentina, with talk of saving fifty-four thousand square miles of forest in Tierra del Fuego, now flooded and endangered by dam-building beavers from North America. “You can see their lakes from an airliner,” said Donlan. “It wouldn’t be cheap, but the alternative is beavers making their way to Patagonia.”

  Campbell and Donlan’s exploratory forays, onto an archipelago better approximating the mainland, give hint of the island campaign’s inevitable destination. It should go without saying that the plague of biological invasions did not begin or end on the shores of oceanic islands. “We must make no mistake; we are seeing one of the great historical convulsions in the world’s fauna and flora,” wrote Charles Elton in his 1957 book, The Ecology of Invasions by Animals and Plants. Elton was a founding and visionary ecologist from England who drew the first and most lasting portrait of a world eating itself alive. “We are living in a period of the world’s history when the mingling of thousands of kinds of organisms from different parts of the world is setting up terrific dislocations in nature. We are seeing huge changes in the natural population balance of the world.”

  Elton wrote of African mosquitoes inadvertently shipped to Brazil, igniting “one of the worst epidemics Brazil has ever known.” During the disaster, also, “hundreds of thousands of people were ill, some twenty thousands are believed to have died, and the life of the countryside was partially paralysed.” Elton charted the wreckage of the chestnut blight, a fungus from Asia that spread like fire to the ecological ruin of the dominant tree of the eastern U.S. forest. He foresaw the dangers of the sea lamprey sneaking through the gates of the Erie Canal, on its way to extinguishing three native species of Great Lakes fish; he presaged the ecological catastrophe of the European zebra mussel, ferried to U.S. waters in the ballast tanks of transatlantic cargo ships and now clogging pipes and smothering life, threatening dozens of native mussels, and costing billions of dollars to fight it.

  The world has not gotten any safer since Elton first sounded the alarm. The new global village trades not only in electronics and soybeans but also in weeds, disease, insect pests, and more of the familiar cast of misplaced mammals—an epidemic of epidemics. In the United States alone, some fifty thousand alien invaders have been helped ashore and across the borders. The invaders include more than a billion rats and one hundred million house cats, the latter of which have been implicated in the demise of perhaps a billion small mammals and lizards and birds every year. U.S. forests are serving as barnyards and feedlots for four million feral pigs. One economic accounting of the invaders’ damages comes to $120 billion per year, with a discomforting caveat: “If we had been able to assess monetary values to species extinctions and losses in biodiversity, ecosystem services, and aesthetics,” wrote David Pimentel and his research colleagues, “the costs of destructive alien invasive species would undoubtedly be several times higher.”

  Americans have been slow to concern themselves with these figures, certainly if stray cats are any measure. In 2008, in Galveston, Texas, a man who shot one feral cat as it was chasing a rare shorebird was arrested and faced up to two years in jail and a sixty-thousand-dollar fine before the charges were overturned. There are now organizations throughout the country actually promoting and feeding feral cat colonies. They are operating very successfully in Hawaii, the U.S. capital of extinction and endangerment, where some of the rarest birds on the planet are still being taken by the subsidized cats.

  New Zealanders, on the other hand, have taken the practice of killing for conservation to the level of civic duty. In the same way that a coterie of Audubon Society members might gather with their binoculars for a Saturday-morning bird walk through Central Park, citizen groups in New Zealand are now marching into their local woods armed with snap traps. Such is the state of conservation in an island nation whose vanishing native fauna has already been picked half clean.

  “Places when I was a kid wandering around the bush, I used to see and hear kokako,” said Bruce Thomas, the former battler for Breaksea. “I used to sit out on the ridges and hear kiwi. They don’t exist anymore. They’re all gone. One day you wake up and say, ‘Oh, I haven’t heard a gray warbler for a long time.’ The bush is going silent.”

  Thomas is now a freelance conservationist, bent on supplying New Zealand’s rat-killing community with the proper tool for the job. In his toolshed he has developed a rattrap that is lighter (a trapper can carry 150 in a backpack), more foolproof (featuring a trigger that prevents even the most thumb-struck handyperson from smashing his own fingers), and ultimately more deadly. “I’m not out to make my first million dollars,” said Thomas. “I’m out to take my first million rats.”

  Thomas’s trap kills quickly. Ninety-nine of every one hundred rats tripping one die of a crushed head or broken neck. “They’re all head shots,” said Thomas. “Death should be instant.”

  More are agreeing on that. The New Zealand Department of Conservation has over the past decade been replacing its venerable snap traps with new precision designs that kill far more quickly. And three young entrepreneurs from Wellington, calling their little company Goodnature, have built what they believe is an even better rattrap, featuring a plastic tube and a CO2 cartridge that propels a plastic plunger with head-pulverizing force. The device—named the Henry—not only renders rat or stoat or possum instantly dead, but also automatically resets itself to await the next victim. “Killing is part of our culture,” said Stu Barr, cofounder of Goodnature. “But it’s not the animal’s fault they’re here. It’s our fault really. We’ve got to treat them humanely, until we kill them.”

  In the Kiwis’ invaded kingdom, the kill trap has become an icon of conservation; the fence is another. One of particularly epic proportions has recently gone up in the center of the country’s North Island. The fence—the last link of it erected in 2006—stands eight feet high and thirty miles around, enclosing in steel mesh a twelve-square-mile mountain island of forest, what its builders hope will someday become a sanctuary of primeval New Zealand. The Maungatautari Ecological Island is financed and run by a citizens’ trust, whose written aim is no less than “to restore the dawn chorus, to fill the forest to capacity with native birds, insects, reptiles, frogs and other wildlife, and to share it with all New Zealanders.”

  As prerequisite, managers of Maungatautari have emptied their fenced forest of all mammalian invaders. Their next step is to reassemble the forest’s conspicuously missing pieces, its kiwi and kokako, its giant weta and tuatara. And the ultimate prize now being quietly considered for transfer to the confines of Maungatautari is the reigning icon of New Zealand’s fight for life, a bird once believed to be extinct.

  LONG WALK HOME

  At the turn of the second millennium, in the years following the kakapo’s terminal diagnosis and subsequent admission to intensive care, the patient miraculously rallied. Following that bumper crop of rimu nuts on Codfish Island in the summer of 2001, the kakapo responded with a crescendo of booming and mating, and the next spring with a bumper crop of chicks. Twenty out of twenty-one female kakapos on Codfish mated. And each, of course, had a midwife at her side. As the nesting season hit high gear, Don Merton and crew matched pace through the nights, candling eggs, nursing chicks, removing infertile eggs with hopes of new layings. By the time the r
ush of 2002 was through, an army of exhausted nest-minders had welcomed another twenty-four kakapos into the fold, jumping the world population to the dizzying sum of eighty-six birds.

  The years following were spent waiting for another like 2002. So much depended on the fickle fruiting schedule of the rimu trees, and all was precariously limited to the one island of Codfish—the only place on Earth where the kakapo still boomed and bred. The rimus’ next substantial fruiting came in 2008; the kakapos responded with six chicks. More rimus fruited the following year, and this time the roof blew off. The year 2009 went down as the greatest in kakapo conservation history. Birds mated multiple times; some laid a second clutch. Those needing assistance were artificially inseminated. By the time the books were closed on the kakapo’s record-breaking breeding season, the population had vaulted to 124 birds.

  But there had developed a dark side to the kakapo’s booming fortunes. One of the diseases most feared for the little cooped-up population on Codfish had already begun to show symptoms. Sperm of male kakapos were sprouting extra heads and tails. Eggs were lying infertile. The little band of inbred kakapos was coming apart at the genes.

  To no great surprise. All but one kakapo had originated from a tiny remnant of survivors on Stewart Island. The one exception was the lovable old bird from Fiordland named Richard Henry. The kakapo that Merton had pulled from the brink in the Esperance Valley in 1975, the sole carrier of Fiordland blood, had in his thirty years of island life sired all of three offspring, none of which had yet entered the mating game. In the intervening years Richard Henry had shown only sporadic interest in competing with younger males. He was blind in one eye, likely an old battle wound. It was quite possible that the kakapo’s knight in moss green armor was more than a century old. Seasons would go by when Richard Henry’s hormones no longer responded to the ripening of the rimu. Merton would coddle and coax his beloved kakapo, following him around with treats of apple, enticing him at every turn with offerings of more food, hoping to fatten the grand old parrot for one more go on the courting grounds.

  The prospect of rescuing the kakapo on the ebbing virility of Richard Henry Kakapo was but half the worry. Beyond the genetics lay another bottleneck, of space. In running up their numbers, the Codfish kakapos had run themselves out of room. (A single kakapo might command 150 acres of territory, wandering twenty miles in a night.) The island-bound birds had begun to exhibit anxieties. Young males had started breaking into nests and attacking chicks. Codfish had gotten dangerously crowded.

  Merton, the man who had once lobbied so relentlessly for taking the kakapos into hand, now found himself campaigning to turn them loose. The time had come for someplace big enough and safe enough to let the nursemaids stand back and let the kakapos prosper on their own.

  Such places made for a short list. There was Campbell Island, forty-four square miles of predator-free wilderness far adrift in the Southern Ocean—perhaps too far adrift. There was no telling how the immigrant kakapo would fare in this foreign land, or how the Campbell ecosystem might in turn fare with this bizarre new bird in the mix.

  There had also been talk of clearing the predators from Stewart Island, third largest island of New Zealand and a former home of the kakapo. Stewart, though, came with people, some of whom held certain opinions about government helicopters dropping poison from the sky, some of whom believed that their pet cats came before kakapos.

  Lately those now in charge of the kakapo’s survival have their eyes focused on Fiordland’s Resolution Island, where more than a century ago the man Richard Henry attempted the first kakapo rescue. In July 2008 eradication crews returned to vanquish Henry’s demon, trapping what they believed to be all 258 stoats over all thirty-one square miles of Resolution. However romantic the notion of the kakapo’s returning to Resolution Island, the reality comes with a cold splash. For there remain mice on Resolution. With the mice there remains a constant lure for mainland stoats contemplating the crossing, and with the stoats a commitment of eternal vigilance in guarding the island’s shores.

  Those now in charge of the kakapo’s survival, it should be noted, no longer include Don Merton. After thirty years at the forefront of kakapo research and rescue, Merton retired in 2005. He has since volunteered his services to the kakapo team; the team has not since taken up his offer. For Merton the physical separation from his birds—Richard Henry above all—has weighed heavily. “It is a huge psychological wrench to no longer be intimately involved, after half a lifetime of intense association with this remarkable creature,” said Merton. “I regard him almost as one of the family.”

  Merton would badly love to see Richard Henry back home, if such a place still exists. However much Resolution may now stand as the kakapo’s most immediate hope for sanctuary, it ultimately renders the bird an orphaned refugee whose mother country died years ago.

  Or maybe not. There remains at least one place that might serve for a homecoming. It survives as a spectacularly towering amphitheater of sheer rock walls high in the wildest reaches of Fiordland. Sinbad Gully was one of the last two valleys of Fiordland found to harbor kakapo, the place where Merton as a fledgling wildlife officer fifty years earlier began his lifelong search. There is good reason that the Sinbad kakapos held out so long, even as their last bastions fell. Those skyscraping slopes spanned a diversity of life zones that harbored a cornucopia of kakapo food. Those forbidding walls were the last fortress of Fiordland to be stormed by stoats.

  Merton believes that Sinbad could be that fortress again. “It’s a natural mainland island,” he said. Sinbad is surrounded on three sides by sheer cliffs and on the fourth by the sea. The gully is a geological stoat fence. “Stoats are capable of coming down out of the top four to five thousand feet,” said Merton, “but it wouldn’t happen very often.” His idea—and he is not alone in the suggestion—is to clear the valley of predators, bring the kakapo home, and guard the few entrances against reinvasion. Or maybe not.

  “It is not high on the current list,” answered Mick Clout, chair of the kakapo advisory council, “but it remains an option.”

  Which is where the fence of Maungatautari comes in. Maungatautari, lying inland, may lack the majestic aura and romantic resonance of Fiordland’s Sinbad Gully. But it is nevertheless the mainland, it is native kakapo range, and it is all but waiting. Tentative plans are to bring a few male kakapos to Maungatautari as early as 2011, for a trial visit. Everyone will be watching, to see if the fence holds them, to see if the forest suits them, to listen toward the hills for the beating of a heart.

  ONE LAST SONG

  With the first of September 2010, on the cusp of another breeding season on Codfish Island, came a report from the kakapo recovery team’s lead scientist, Ron Moorhouse. The rimus had fruited well, said Moorhouse. It was shaping up to be another good year for kakapos.

  But there was bigger news concerning the castaways of Codfish. Richard Henry Kakapo had been found to be sick. He’d been infected by a protozoan parasite, for how long nobody knew. But it was likely his caretakers had at last discovered the reason he’d been struggling to put on weight, the reason why the kakapo species’ most desperately needed father figure had never boomed on Codfish.

  The disease, it turned out, was treatable. Kakapo conservationists poisoned the parasites with antibiotics, eradicating every last one of the little invaders from Richard Henry’s beleaguered body.

  Richard Henry Kakapo had since grown the fattest he’d been in years. At last check, reported Moorhouse, his breast and belly had taken on a spongy feel, the telltale sign of a male kakapo getting ready to boom.

  ACKNOWLEDGMENTS

  I owe the idea for this book to Will Murray, longtime sounding board and conservation sage, who alerted me to a radical new wildlife rescue that could “manufacture millions more birds with a swipe.” If in my two hundred pages I have conveyed the story half as well as Murray did in his opening five-minute pitch, then I have exceeded my goal.

  The financial task of
gathering this story was greatly eased by a journalism fellowship from the Alicia Patterson Foundation. Without their help, I might never have witnessed the epic display of auklets at Sirius Point, or peeked into the fantastic hobbit forests of Richard Henry’s homeland. To Peggy Engel and the Patterson folks, I remain forever grateful—as I do to my friends and colleagues Josh Donlan, Will Murray, Bill Ripple, and Angie Sosdian, who recommended they choose me.

  To the more than one hundred scientists, conservation professionals, trappers, shooters, pilots, and animal rights advocates who shared with me their stories, I am indebted. Among them, I owe special thanks to Stacey Buckelew, Vernon Byrd, Gregg Howald, Helen James, Ian Jones, Lisa Matisoo-Smith, Don Merton, Rowley Taylor, Bernie Tershy, and Bruce Thomas, who each reviewed one or more chapters for their accuracy.

  My ventures to certain otherwordly places were made even more memorable by certain special hosts. Captain Billy Pepper and able crew of the M/V navigated a mindbending tour of the Aleutians with great skill and matching humor. Jeff Williams and Poppy Benson of the U.S. Fish and Wildlife Service originally helped secure my space on the —what has to be one of the most coveted berths on any seagoing vessel. And Lisa Spitler helped make Adak, “Birthplace of the Winds,” a most hospitable visit.

  In New Zealand, I could not have imagined more generous hosts than Alan and Diane Hay in Auckland, Bruce and Pam Thomas in Nelson, the McClelland family in Invercargill, and the Cumbo clan in Dunedin. And if not for the last-minute heroics and monster truck of Vic and Chandra Vickers during the Blizzard of 2010, I would never have even made my flight out of D.C.