Sirocco’s chaperone, a Department of Conservation ranger named Alisha Sherriff, had brought along a little metal container, which she passed among the visitors. Inside was half a cup’s worth of Sirocco’s shit.
“Have a good sniff,” she suggested.
“It’s earthy!” one woman exclaimed.
“I think it smells smoky, with notes of honey,” Sherriff said. When the container came to me, I couldn’t detect any honey, but the bouquet did strike me as earthy, with hints of newly mown hay. Sherriff had also brought along a zip-lock bag with some of Sirocco’s feathers. These too had a strong, sweetish scent.
New Zealand birds tend to smell, which was not a problem when the islands’ top predators were avian, since birds hunt by sight. But as mammals hunt with their noses, it’s become yet another liability. (A few years ago a Christchurch biologist was awarded a $400,000 grant to investigate the possibility of developing some sort of “deodorant” for ground-nesting birds.)
Sherriff explained that Sirocco had been born on Codfish Island in 1997, but as a chick he had come down with a respiratory infection and so had been removed from his mother and raised in isolation. By the time he was well enough to rejoin the other kakapo, he’d decided he preferred people. During breeding season he’d try to mate with the rangers on Codfish while they were walking to the outhouse. A special barrier was built to try to prevent the encounters, but Sirocco turned out to be too determined.
“When you’ve got a three-kilo bird crashing through the bush in the middle of the night, there’s quite a high risk of people lashing out unintentionally,” Sherriff said. It had been decided that for Sirocco’s own safety, he’d have to be moved. He now lives hundreds of miles from Codfish, on an island whose name the Department of Conservation won’t disclose. For the sake of genetic diversity, Sirocco’s semen had been collected, by means of what Sherriff described as a “delicate massage,” but his sperm count had proved too low to attempt artificial insemination.
After about half an hour with Sirocco, we were hustled out to make room for the next tour group. Russell and I passed back through the gates and drove down to a restaurant at the base of the mountain, where we’d arranged to have dinner with Matt Cook, the reserve’s natural-heritage manager. Cook told us that it had taken teams of exterminators three years to eliminate mammals from inside the fence and that they’d never managed to finish off the mice. The entire perimeter was wired so that when, say, a section of fence was hit by a falling branch, a call automatically went out to a maintenance crew.
“This always happens at 3 a.m. on a Saturday morning,” he said. If the fence was breached, Cook reckoned, the crew had about 90 minutes to repair it before rats would find the opening and sweep back in.
Today invasive species are everywhere. No matter where you are reading this, almost certainly you are surrounded by them. In the northeastern United States, common invasive plants include burdock, garlic mustard, purple loosestrife, and multiflora rose; invasive birds include starlings, rock pigeons, and house sparrows; and invasive insects include Japanese beetles, gypsy moths, and hemlock woolly adelgid. Texas has more than 800 nonnative plant species, California at least 1,000. Even as New Zealand has been invaded by nonnative species, its native species have invaded elsewhere. Potamopyrgus antipodarum, or, as it is more commonly known, the New Zealand mud snail, is a tiny aquatic snail about the size of a grain of rice. It can now be found in Europe, Asia, Australia, the Middle East, and the American West, and it has proved such a successful transplant that in some parts of the world it reaches densities of half a million snails per square yard. In an irony perhaps only Kiwis can appreciate, a recent study in Utah found that mud snails were threatening populations of rainbow trout, a fish imported at great expense to New Zealand in the 1880s and now considered an invader there.
The project of reshuffling the world’s flora and fauna, which began slowly with the spread of species like the Pacific rat and sped up thanks to the efforts of acclimatization societies, has now, with global trade and travel, accelerated to the point that on any given day something like 10,000 species are being moved around just in the ballast water of supertankers. Such is the scale of this remix that biologists have compared it to reassembling the continents. Two hundred million years ago, all of the world’s landmasses were squished together into a single giant supercontinent, Pangaea. We are, it’s been suggested, creating a “new Pangaea.”
One response is simply to accept this as the planet’s destiny. Yes, the invaders will inevitably choke out some local species, and there will be losses, especially on islands, where, unfortunately, much of the world’s diversity resides. But people aren’t going to stop shipping goods and they aren’t going to stop traveling; therefore we’re just going to have to learn to live in a Pangaea of our own making. Meanwhile, who even knows at this point what’s native and what’s not? Many species that people think of as a natural part of the landscape are really introductions that occurred before recent memory. For instance, the ring-necked pheasant, the official state bird of South Dakota, is an import from China.
“It is impractical to try to restore ecosystems to some ‘rightful’ historical state,” a group of American researchers wrote a few years ago, in Nature. “We must embrace the fact of ‘novel ecosystems’ and incorporate many alien species into management plans, rather than try to achieve the often impossible goal of eradicating them.”
New Zealanders are nothing if not practical. They like to describe the national mindset as “the No. 8 wire mentality”; for much of the country’s history, No. 8 wire was used to fix livestock fences and just about everything else. Nevertheless, Kiwis refuse to “embrace” novel ecosystems. In the past few decades they have cleared mammalian predators from 117 offshore islands. The earliest efforts involved tiny specks, like Mokopuna, or, as it is also known, Leper Island, which is about the size of Gramercy Park. But more recently they’ve successfully de-ratted much larger islands, like Campbell, which is the size of Nantucket. With its predator-free islands and its fenced-in reserves and its massive poison drops from the air, New Zealand has managed to bring back from the very edge of oblivion several fantastic birds, including the kakapo, the South Island saddleback, the Campbell Island teal, and the black robin. At its lowest point, the black robin was down to just five individuals, only one of which—a bird named Old Blue—was a fertile female. (When Old Blue died, her passing was announced in parliament.)
Meanwhile, by tackling larger and larger areas, New Zealanders have expanded the boundaries of what seems possible, and they increasingly find their skills in demand. When, for example, Australia decided to try to get rid of invasive rodents on Macquarie Island, roughly halfway between Tasmania and Antarctica, it hired a New Zealander to lead the effort, and when the U.S. National Park Service decided to get rid of pigs on Santa Cruz Island, off the coast of Southern California, it hired Kiwis to shoot them. The largest rat-eradication effort ever attempted is now in progress on South Georgia Island, a British territory in the South Atlantic with an area of nearly a million acres. A New Zealand helicopter pilot was brought in to fly the bait-dropping missions. One day when I was driving around with James Russell, he got an e-mail from Brazil: the government wanted to hire him to help it get rid of rats on the Fernando de Noronha archipelago, off Recife. David Bellamy, a British environmentalist and TV personality, has observed that New Zealand is the only country in the world that has succeeded in turning pest eradication into an export industry.
The idea of ridding all of New Zealand of its mammalian predators was proposed by Paul Callaghan, a world-renowned physicist, in a speech delivered in Wellington in February 2012. In scientific circles Callaghan was celebrated for his work on nuclear magnetic resonance; to Kiwis he was probably best known for having recently been named New Zealander of the Year. At the time he gave the speech, Callaghan was dying of cancer, and everyone who heard it realized that it was one of the last he would deliver. (He died the following month
.)
“Let’s get rid of the lot,” Callaghan said. “Let’s get rid of all the predators—all the damned mustelids, all the rats, all the possums—from the mainland.
“It’s crazy,” he continued, referring to his own proposal. But, he went on, “I think it might be worth a shot. I think it’s our great challenge.” Callaghan compared the project to the moon landing. It could be, he said, “New Zealand’s Apollo program.”
I listened to Callaghan’s speech, via YouTube, on one of my last evenings in New Zealand. It seemed to me that what he was proposing was more like New Zealand’s Manhattan Project than its Apollo program, though I could see why he hadn’t framed it that way.
New Zealand’s North Island is roughly 44,000 square miles. That means that it’s nearly a thousand times bigger than the largest offshore island from which predators have at this point been eradicated. James Russell serves as an adviser to Predator Free New Zealand, the group that was formed to pursue Callaghan’s vision. I asked him about the feasibility of scaling up by such an enormous amount. In response he showed me a graph: the size of the islands from which predators have been successfully removed has been increasing by roughly an order of magnitude each decade.
“It is a daunting scale that we’re talking about,” Russell told me. “But then you see the rate at which we have scaled up.
“Some people think scientists should just be objective,” he went on. “They sit in the lab, they report their results, and that’s it. But you can’t separate your private life from your work life. So I do this science and then I go home and think, Wouldn’t it be great if New Zealand had birds everywhere and we didn’t have to worry about rats? And so that’s the world I imagine.”
Listening to Callaghan on YouTube also reminded me of a point that Nick Smith had made the day of the saddleback release: in New Zealand, killing small mammals brings people together. During my travels around the country, I found that extermination, weird as it may sound, really is a grassroots affair. I met people like the Adsheads, who had decided to clear their own land, and also people like Annalily van den Broeke, who every few weeks goes out to reset traps in a park near her home in the suburbs of Auckland. In Wellington, I met a man named Kelvin Hastie, who works for a 3-D mapping company. He had divided his neighborhood into a grid and was organizing the community to get a rat trap into every 100-square-meter block. “Most of the neighbors are pretty into it,” he told me.
Just about everyone I spoke to, including Hastie, expressed excitement about the latest breakthrough in extermination technology, a device designed by a company called Goodnature. And so on my last day in the country, I went to visit the company’s offices. They were situated in a drab stretch of anonymous buildings not far from one of Wellington’s best surfing beaches. When I arrived, I noticed a dead stoat in a plastic bag by the door. Apparently it had been killed quite recently, because it was still very much intact.
Robbie van Dam, one of the company’s founders, showed me around. In the first room several young people were working at standing desks, on MacBooks propped up on cardboard boxes. A small kitchen was stocked with candy and half-empty bottles of wine. In a back room bins of plastic parts were being assembled into an L-shaped machine that resembled a portable hair dryer. Van Dam pulled out one of the finished products, known as the A24. At one end there was a CO2 canister of the sort used in bicycle pumps. Van Dam uncapped the other end and pulled out a plastic tube. It was filled with brown goo. In the crook of the L was a hole, and in the hole there was a wire. Van Dam gingerly touched the wire, and a piston came flying out.
The A24 is designed to be screwed to a tree. The idea is that a rat, smelling the goo, which is mostly ground nuts, will stick its head into the hole, trip the wire, and be killed instantly. The rat then falls to the ground, and the device—this is the beauty part—automatically resets itself. No need to fish out rotten eggs or decaying flesh. Each CO2 canister is supposed to be good for two dozen rats or, alternatively, stoats—hence the name. (For stoats there’s different bait, made of preserved rabbit.) Van Dam also showed me a slightly larger machine, the A12, designed for possums.
“The humaneness problem was probably the hardest part,” he told me. In the case of possums, it had turned out that a blow to the head wasn’t enough to bring about quick death. For that reason the A12 is designed to fill the animal’s skull with carbon dioxide and emulsify its brain. Goodnature also sells canisters of possum bait, laced with cinnamon. I picked up a tube. “12 out of 12 possums choose this as their final meal,” the label said.
Even taking the long view—the very long view—the threat posed to New Zealand’s fauna by invasive species is extraordinary. It may be unprecedented in the 80 million years that New Zealand has existed. But we live in an age of unprecedented crises. We’re all aware of them, and mostly we just feel paralyzed, incapable of responding. New Zealanders aren’t just wringing their hands, nor are they are telling themselves consolatory tales about the birth of “novel ecosystems.” They’re dividing their neighborhoods into grids and building better possum traps—ones that deliver CO2 directly to the brain.
A couple of miles from Goodnature’s headquarters is a rocky beach where little blue penguins sometimes nest. The beach is infested with rats, which can attack the nests, so Goodnature has installed some A24s along it, and van Dam took me down to have a look. It was a beautiful windy day, and the surf was high. Under the first A24, which was attached to a gnarly bush, there was nothing. Often, van Dam explained, cats or other rats drag off dead animals that have dropped from the A24, so it’s not always possible to know what, if anything, has been accomplished. This had proved to be something of a sales problem.
“If people didn’t find something dead under there, they were really disappointed,” he said. Goodnature now offers a digital counter that attaches to the A24 and records how many times the piston has been released.
Under the second A24 there was a dead mouse; under the third and fourth, nothing. Under the fifth were two ship rats, one freshly killed and the other just a clump of matted fur with a very long tail.
AMY MAXMEN
Digging Through the World’s Oldest Graveyard
FROM Nautilus
TWO HAMMERS, TWO shovels, four rifles. They carried their own tools. Zeresenay Alemseged, a young and driven Ethiopian fossil hunter, joined by four armed soldiers and a government official, was on a mission to the Afar Depression, a region shaped like a tornado in Ethiopia’s Great Rift Valley. The Afar is bone-dry, scorching hot, and riddled with scorpions and vipers. It is regularly shaken by earthquakes and sinking deeper into the earth as the converging tectonic plates beneath it pull apart, and molten magma bubbles up through the cracks. When the magma cools, it forms sharp, basaltic blocks.
Along the road the boulders blocked Alemseged’s path. He had to stop the car, lift the boulders, drive further, repeat. Dry riverbeds were smoother, but frequently the tires sank in the fine sand, and the men, sweating in the afternoon sun, pushed the Jeep onward.
Alemseged was headed to the most dangerous spot within the Afar, which even Indiana Jones types avoided because of constant conflicts between local tribes. The armed soldiers were his security. Alemseged had no salaried scientific position and refused to accompany teams led by accomplished researchers going to safer areas with fat grants. If he struck out on his own, he felt sure he could discover academic gold: ancient traces of humankind’s past. This meant funding the expedition out of pocket. “I was the driver, so I didn’t need to pay a driver; I was the cook, so I didn’t need to pay a cook; and I was the only scientist,” Alemseged said.
His aim was to explore an area called Dikika, across from a bank on the Awash River where an American paleontologist, Donald Johansen, had discovered Lucy in 1974. Her ancient skeleton’s partially human, partially chimpanzee features were a clear indication of our descent from the apes. Dikika was the logical next place to look for more fossils, but no one had done so because of the r
isk presented by battles waged over water and land between the Afar and the Issa, pastoral tribes who inhabit Dikika. But Alemseged, who goes by Zeray (pronounced Zeh-rye), was not deterred.
Alemseged’s bare-bones team reached a vast plain of sand and volcanic ashes. He knew this sediment yielded the type of fossils he was after. In December of 2000 one of the men spotted the top of a skull the size of a small orange in the dirt. Slowly, over a period of years, he and his colleagues carefully unearthed a petite skeleton of a child who had likely died in a flood and been buried in soft sand, 3.3 million years ago. She was a member of Lucy’s species, Australopithecus afarensis, from a period about halfway between today and the time when our lineage went one way and that containing chimpanzees went the other. In 2006 Alemseged and his colleagues published their findings in Nature.
The child was named Selam—a word for peace in several Ethiopian languages, a wish to end the fighting in Dikika. Selam’s gorillaish shoulder blades and long fingers betrayed a penchant for swinging on branches. But bones at the base of her head showed that she held it upright and therefore walked on two legs. The size of her skull suggested that her brain developed slowly through early childhood, a distinct characteristic of humans from long before modern humans evolved.
“It’s the earliest child in the history of humanity,” Alemseged said, enunciating each word slowly. “That discovery was 100 percent Ethiopian. It was by Ethiopians, on Ethiopian land, led by an Ethiopian scientist.”
The Best American Science and Nature Writing 2015 Page 23
