Rat Island (19 page)

Hawaii was neither the last nor the least of the Pacific islands to have its popular rendition of history shredded by rats. Something similar seems to have happened on a sixty-four-square-mile protrusion of treeless terrain two thousand miles west of Chile named Rapa Nui, more popularly known as Easter Island. Originally rising to fame on the riddle of its stone-faced monuments—thirty feet tall and eighty tons heavy, staring blankly out to sea from the middle of nowhere—the island's reputation had more lately come to center on the culture that had placed them there. Easter Island had become a parable of humanity's ecocidal tendencies, largely owing to the vivid interpretations of the scientist and bestselling author of
Collapse
Jared Diamond: “In just a few centuries, the people of Easter Island wiped out their forest, drove their plants and animals to extinction, and saw their complex society spiral into chaos and cannibalism. Are we about to follow their lead?”

Diamond's sobering summary involved Easter Island's Polynesian settlers cutting forest faster than it grew. As the trees ran short, so did the fuel of their fires and the fabric of canoes and houses and livelihoods. Life got hard, war broke out, society collapsed. “As we try to imagine the decline of Easter's civilization,” wrote Diamond, “we ask ourselves, ‘Why didn't they look around, realize what they were doing, and stop before it was too late? What were they thinking when they cut down the last tree?' ”

In 2007 the archaeologist Terry Hunt, from the University of Hawaii at Manoa, and his colleague Carl Lipo, from California State University, Long Beach, answered the question for the missing Polynesians. Maybe, argued Hunt and Lipo, those felling the last tree did so with neither ax nor aforethought. Maybe Easter Island had fallen not to short-sighted humans, but to a feeding frenzy of Pacific rats.

Hunt and Lipo's scenario of Easter Island's demise, like Athens's of the Ewa Plain's, began with the arrival of the Polynesian voyagers around
A.D.
1200, accompanied, of course, by their rats. The rats proliferated in a predator-free paradise, finding millions of palm trees, each producing an annual crop exceeding 250 pounds of nuts. A single mated pair of rats, on an island with limitless food and no predators, could double their numbers every forty-seven days, becoming seventeen million in three years. Almost all the plants extinguished from Easter Island would prove to be rat favorites. One shrub that did survive featured a seed that seemed to germinate better for having been chewed.

In 2006, Hunt and Lipo published their solution to Diamond's riddle by way of the journal
Science.
“The ecological catastrophe of Rapa Nui had a complex history that cannot be reduced to psychological speculations about the motivations of people who cut down the last tree. Indeed, the ‘last tree' may simply have died, and rats may have simply eaten the last seeds. What were the rats thinking?”

Those still harboring doubts about the rats' omnipotence were to be directed to another recent paper, this one beginning with the far broader question: “Have the Harmful Effects of Introduced Rats on Islands Been Exaggerated?” In their answer, David Towns, from the New Zealand Department of Conservation, and two colleagues produced a withering compilation of extinctions and decimations, of birds, bats, bandicoots (a rabbitlike cousin to the kangaroo), worms, insects, spiders, crabs, frogs, snakes, lizards, shrews, and shrubs, all with histories of disappearances linked to the arrivals of brown rats, black rats, and Pacific rats. The trails of carnage led from one-acre islands in the French West Indies to the 607 square miles of Hawaii's Oahu, across the Caribbean, Mediterranean, and Tasman seas, across the Indian, Atlantic, and Pacific oceans. Any more questions? In yet another synthesis of damages, researchers from the University of Hawaii at Manoa seconded the Towns report, crediting the big three species of rats with having driven or assisted 103 species of birds, reptiles, amphibians, and mammals to extinction.

Even the humble house mouse—of the species better known as invader of pantries and kitchen cabinets—had recently unveiled an alter ego as voracious slayer of island giants. Far off the southernmost coast of South Africa on Gough Island, home of the last breeding colony of the Tristan albatross, video cameras trained on their nests captured what had to be seen to be believed. Gangs of mice were rushing from out of the dark to attack birds three hundred times their size. The mice were chewing holes in the rumps of seventeen-pound albatross chicks as they sat, eating the living birds from the inside out.

And no modern chronicle of rodent overachievement would be complete without the saga of Razza the rat. Razza was a wild brown rat captured, named, and released in November 2004 under intensive watch by a team of biologists led by the University of Auckland's James Russell. Attempting to measure the difficulties of capturing or even detecting a single invading rat, Russell's team radio-collared Razza, turned him loose on a twenty-three-acre island in northern New Zealand's Hauraki Gulf, then set about tracking him down.

Razza had other ideas. For weeks he repeatedly refused all invitations to plastic tunnels and snap traps and turned down all sensory enticements from fish oil to chocolate. Then his radio signal vanished. To the embarrassment of his watchmen, Razza had escaped.

Following a tip from villagers on a neighboring island, Russell and crew went looking. And there, to their astonishment, they found a rat scat, identified by DNA fingerprinting as Razza's. The roving rat had swum a quarter mile of open water.

Again the scientists gave chase, this time siccing trained dogs on Razza's scent. And for another six weeks, the rat continued to run rings around them all, until finally—four and a half months into the chase—with a momentary lapse of caution and a meat-baited trap—the odyssey of Razza came to its dead end.

Russell and colleagues concluded their part of the scientific adventure with a newfound sense of respect and a healthy serving of understatement: “Our findings confirm that eliminating a single invading rat is disproportionately difficult.”

Q
UIETLY
C
ONSERVING
N
ATURE

And so the rat's reputation as supernatural escape artist and ecological wrecking ball expanded in tandem with the island conservationists' escalating offensive. The state of eradication art had taken great leaps in the forty years since the birdman Don Merton and the schoolteacher Alistair McDonald had almost haphazardly cleared the nubbin of Maria Island with a few handfuls of warfarin. There were now helicopters navigating by satellite, air-dropping poison by the tens of tons, striking with precision measured to the meter. The eradicators' ranks included hormonally engineered pigs and Mata Hari goats diabolically luring herdmates to slaughter. Islands approaching the size of small states and archipelagos spanning the seas were being rearranged and restored to more pristine pasts under strategic assault and rescue.

The fight had spread far beyond the pioneering Kiwis and Aussies in their embattled island nations. The managers of the Alaska Maritime National Wildlife Refuge had cleared upward of forty islands of foreign foxes, resetting the stage on the most prolific seabird chain of the northern hemisphere. The crews of Island Conservation and their Mexican allies had conquered invaders across two dozen islands of Baja, with their sights on far broader horizons. They were squaring off against mink and raccoons in the Scott Islands of British Columbia, mice in the Farallons of California, macaque monkeys in Puerto Rico, and goats, cats, and rats in the Galápagos.

And now all attentions had come to focus on Rat Island, and the pending attempt at the third-largest rat eradication ever, in a devil of a destination, with a price tag running into the millions. Its planners readily assembled the major components. In brodifacoum they had a proven poison, and in Pete McClelland they had ready advice from the world's record holder at rat eradication. With the U.S. Fish and Wildlife Service they had the keys to the refuge and the comradeship of the most knowledgeable sailors and pilots and naturalists of the Aleutians. And soon they had the millions too.

Rat Island's eradication went from dream on a drawing board to economically viable work plan when the Nature Conservancy joined the campaign. The Nature Conservancy—owner and steward of the largest private network of nature sanctuaries in the world (a wild kingdom spanning more than a hundred million acres of premier ecological real estate in some twenty countries) and perennially ranked among the top twenty philanthropic organizations in the world—knew a thing or two about orchestrating grand conservation ventures. Moreover, the conservancy as of 2004 had just co-authored a plan with the World Wildlife Fund with an ambition no less audacious than to save the Bering Sea. Tops among the conservation targets were the Aleutian Islands and their unprecedented gathering of seabirds. And chief among the solvable threats to those priorities were predatory invaders. Rat Island was tailor-made for the conservancy's first big splash in a Bering Sea campaign.

The Nature Conservancy came with cash and cachet. It also came with fresh scars from its forays into the emerging practice of conservation by eradication. In as much as the bulldozer had once served as symbolic antagonist to the conservancy's mission, choking weeds and animal pests had since invaded their way to the top of its most-wanted list. Proudly touting the motto Quietly Conserving Nature, the organization had over the years found it ever harder to protect its investments without unwanted noise, in such forms as gunfire and public outcry.

The conservancy's first major foray into the killing arena began in 1978, when it purchased all but 10 percent of Santa Cruz Island, off the coast of Southern California (the rest was eventually incorporated into Channel Islands National Park). The property conveyed a host of rare and indigenous plants and animals, as well as a legacy of livestock threatening to displace them. Cattle, sheep, and pigs had trampled and chewed the island, sending hillsides sloughing into the sea and the island's native life-forms running for cover. Taking inventory of the endangered, conservancy steward Will Murray one day found himself hanging from a rope on the face of a Santa Cruz sea cliff, counting the last three survivors of a wildflower species driven to the edge by marauding sheep. Thereafter Murray's duties as Santa Cruz steward included shooting sheep. The conservancy's new tack of quietly killing for nature went public rather abruptly during the 1984 Summer Olympics in Los Angeles, when the nightly TV broadcast ended with a message from a local station: “Environmentalists killing sheep on Santa Cruz. Story at 11.”

“Then it started,” said Murray.

P
IG
F
IGHT

It was the beginning of a pattern, of scathing letters and damning editorials and accusations that would erupt here and there and wherever the bullets and poisons started flying in the name of conservation. In the mid-1990s the Nature Conservancy found itself again the subject of scorn, this time for killing pigs in defense of Hawaiian rain forests. The pigs—feral, bristly hulks descended from barnyard stock—had taken to rototilling great swaths of the fragile Hawaiian flora, and killing the rarest of birds in innocently diabolical ways. The pits left by the pigs' rootings and wallowings filled with rain, which made ideal breeding grounds for swarms of foreign mosquitoes. And soon Hawaii's native songbirds—some of them down to handfuls of survivors—began dying slow deaths of avian malaria. Neither fences nor the nascent science of feral pig sterilization offered any practical answer to an enemy so firmly entrenched in such impenetrable mountain wildernesses of razor-spined, rain-drenched jungle. So with more amiable options precluded, the conservancy started shooting and snaring Hawaii's feral pigs in its preserves.

Snared pigs did not often die nicely, and People for the Ethical Treatment of Animals, a national animal rights organization, fashioned a national publicity campaign around that fact, posting graphic advertisements of strangling pigs suffering festering gashes. Failing traction in Hawaii, PETA went for maximum publicity at the conservancy's high-rise headquarters in Arlington, Virginia, across the Potomac from the nation's capital. On the first of a two-day offensive, PETA demonstrators—one of them dressed as a pig—picketed outside the conservancy's offices. The Washington press all but ignored them. Conservancy employees spent their lunch hours enjoying the show from the skywalk. On the second day PETA got impatient, and things got physical. A bucket of blood-red paint splashed upon the doorstep. Protesters stormed the building. Ray Culter, the conservancy's director of administration, found himself wrestling with a big, pink, bipedal pig. Culter sent the pig fleeing, minus his head. PETA's remaining troops mounted a last-ditch offensive, lying in a chain across four lanes of city traffic, which brought the handcuffs and paddywagon and an end to the fracas. The conservancy went on killing pigs in defense of its Hawaiian sanctuaries, while back at headquarters, said Culter afterward, “we kept the pig head.”

Years later the Nature Conservancy found itself facing yet another pig fight, this one back on the familiar contentious territory of Santa Cruz Island, but this one adding a few new twists, featuring a bizarre little fox and an unlikely new adversary.

The fox in question was a diminutive island specialty the size of a large kitten with a trusting temperament to match. Numbers of the Santa Cruz island fox in the 1990s had free-fallen from two thousand to less than one hundred, its rescue posing a Solomon-esque dilemma. The fox's demise followed a roundabout route back to the feral pigs that had assumed command of Santa Cruz—pigs that had come to endanger the fox by way of a more problematic accomplice, the golden eagle. Immigrant eagles, enticed from the mainland by the allure of squealing piglets, had taken to snatching the clueless little foxes like candy.