Saving the Galapagos, One Poison-Dropping Helicopter at a Time

In early November of last year, representatives for the Galapagos Islands National Park took the quick jaunt from their main offices on Santa Cruz island to a tiny one, called Plaza Sur, just off Santa Cruz's east coast. They rounded up 40 iguanas: 20 males and 20 females, and carted them back to the park's iguana breeding center.

These iguanas were the park's insurance policy. Soon after gathering the iguanas, a helicopter dropped poisoned blue pellets designed to kill field mice living on the island, an invasive species that had been decimating the iguanas' food supply. Environmentalists saw the move as a last-ditch effort to save the roughly 400 iguanas living on the island, but there was an outside chance that the iguanas would also be poisoned by the pellets.

"It's like surgery. You've got these cancers that are threatening to take out an entire ecosystem, and if you don't operate, the whole system is going to be in decay," said Karl Campbell, who works with Island Conservation, a company dedicated to removing invasive species from islands.

Campbell and Island Conservation worked for months before the helicopters delivered the poison: Designing a pellet that would be devastating to small mammals but uninteresting to iguanas, making a plan of action, and eventually delivering the poison. Nearly a year later, the island is still mouse-free. Just two iguanas died of poisoning.

It's a good thing, too. Scientists are beginning to think that Plaza Sur's land iguanas—some of them hybrids of a male land iguana and female marine iguana—could potentially be a new species. At the very least, the iguanas are unique to Plaza Sur's tiny land mass.

"The Plaza Sur iguana could deserve special acknowledgement," said Gabriele Gentile, one of the world's foremost experts on iguanas. The Italian researcher has been working on and off with Plaza Sur's iguanas since 2003. Though he and his team aren't sure whether the hybrid iguanas will eventually deserve species status, he says there is a "consistent genetic difference" between Plaza Sur's iguanas and those living on other islands.

There are also morphological differences: Hybrid iguanas are generally smaller than land iguanas, and have the face and tail of a marine iguana, but the body of a land iguana.

Like many animals living on the Galapagos archipelago, they have no natural predators on Plaza Sur. But when mice eventually colonized the island, the iguanas quickly had a problem. Iguanas thrive on the Opuntia cactus that grows on the island; mice thrive on the roots. Mice would burrow into the ground, and eat the roots before burrowing into the base of the cactus. Eventually, the cacti would have no way of supporting their weight.

"When strong winds or heavy rains came, they'd end up falling over," Campbell said. "The iguana population definitely couldn't exist without them."

And without iguanas, the whole ecosystem of the island would falter, according to Washington Tapia, director of scientific research at Galapagos National Park.

"It's the most important species on the island. They're the engineers of the ecosystem. Not just the vegetation, but the other animals and birds rely on them," he said. "If we lost the iguanas, we would have lost the island."

That's why Tapia and Campbell didn't take dropping poison from a helicopter lightly. A series of lab tests showed that reptiles and birds aren't as attracted to the blue blocks of poison as mice and rats are. Still, during the operation, there's always the worry that if something goes wrong, it might have devastating effects on an incredibly rare and pristine ecosystem. That's why 40 iguanas were removed from the island.

"When you have an island endemic like this, you have 100 percent of the population that's at potential risk when you do this," Campbell said. "We had a good idea that this would work, but it's not good to have all your eggs in one basket."

*****

I'm walking along a dusty path on Galapagos' largest island, Isabela, the landscape strewn with cacti and dry, prickly trees, when I come across a sign: "Introduced animals hunting area. No Entry."

Beneath the white lettering on the sign are drawings of a pig, a goat, a cow, a cat, and a rat. I hear someone, or something, approaching. I realize it's two men on horseback, accompanied by hunting dogs. Something is off about the men's third horse. Then I realize it's got the carcasses of three boars strung over its back. I see a hog's snout peeking out from behind one of the men. In total, they've got six boars.

Invasive species on the Galapagos are not a new problem. They've been wreaking havoc on nearly each of the 18 major islands in the archipelago, and many of the smaller islands, since humans first discovered them in the early 1500s. (Some ecologists will say that "humans are the most problematic invasive species," and they'd likely be right, but that's for another article.)

When Darwin arrived in the 1800s, he noted wild pigs living on several of the islands, which were likely brought by pirates or early settlers. With human help, or strong tides and a little help from floating debris, mammals have been able to colonize many of the islands. Those populations have had hundreds of years to establish themselves, an easy task when you've no predators to slow you down. According to the Galapagos Conservancy, some islands once had as many as 100,000 goats. Others had as many as 18,000 pigs.

It's not just mammals that are problematic. Farmers, once seen as being at odds with the environment, are being recruited to help control the spread of invasive blackberries, which have strangled out endemic plants on several islands. One researcher told me he was commissioned by the Ecuadorian government to do a study of how many insects were making it to the island aboard shipping vessels on a daily basis. He said the results of the study were so outrageously beyond what both he and the government expected that they forbade him to publish it. He refused to talk to me about it further.

And new introductions remain a problem as well. Instead of having a pirate ship or research vessel pop by every couple months, there are daily flights and shipping boats arriving to Galapagos. Its population is increasing. Tourism is more popular than it has ever been. In 2007, UNESCO placed the Galapagos Islands on its list of World Heritage Sites in Danger, saying the islands "are threatened by invasive species, growing tourism, and immigration."

That cycle had, by that point, become an iterative loop: More visitors and immigrants from the mainland inherently makes it harder to check what's coming to the islands. According to UNESCO, the "growth in immigration and ensuing inter-island traffic has led to the introduction of more invasive species."

That's not to say people living on the islands and government officials alike aren't trying to slow the problem down. Arriving from Ecuador by air, all luggage is closely inspected both before boarding the plane and after arrival. Before boarding an inter-island boat, all bags are checked again. You're not allowed to switch islands with so much as visible mud on your shoes or pants. Invasive species reduction programs have become a priority.

And some locals, such as the ones I've run into on Isabela, make a living hunting feral hogs and goats.

"Do you do this often?" I ask the men.

"All the time," one says to me.

"Is it difficult to find the boars when you're hunting?"

"No, they're everywhere. All over the place," he tells me.

They ride off towards town, where they'll sell the boars, getting paid by weight. Like mice on Plaza Sur, feral hogs are devastating to the Galapagos ecosystem, a place that was untouched by mammals for millions of years. Marc Patry, a researcher with the Charles Darwin Research Station on Santa Cruz, recently wrote that the pigs are "considered one of the most ecologically destructive introduced vertebrates in Galapagos, where they are effective predators of giant tortoise and sea turtle nests, possibly prey upon young tortoises, and, in certain circumstances, compete for food resources with young giant tortoises."

Pigs and goats certainly played a role in the extinction of the Pinta Island tortoise, a subspecies that was made famous by Lonesome George, who died in captivity last year at the ripe age of 100-something. Though mammals put adult tortoises in no danger, it's hard to grow an already slowly reproducing population when all of its eggs are being eaten or trampled.

It's difficult to kill a species living on an island with no natural predators, especially when a population has had, in some cases, more than 100 years to establish itself. On Santiago island, east of Isabela and north of Santa Cruz, pig control efforts date back to 1973. But between 1973 and 1997, there were "waxing and waning feral pig control efforts," according to Patry.

"These variations were related to funding availability, El Niño events, morale fluctuations, or lack of training," he wrote. In 1997, the Galapagos National Park and Charles Darwin Research Center made killing pigs on Santiago a "bi-institutional priority." Efforts were redoubled, hunters were trained, pig detection and killing methods were improved, and today, Santiago is believed to be pig free.

But while scientists at the park have tried controlling invasive species populations with hunting and small-scale poisoning for quite some time, it's not until recently that a quick and complete eradication of an established species was seen as being a possibility. It took roughly 30 years to clear pigs off of Santiago. Pest management teams want to speed things up.

Campbell and Island Conservation specialize in taking one "management action," as he calls it, during times when food supply and populations are naturally at their lowest. The action is quick, surgical, and deadly. It took months of planning to figure out how to take out the mice on Plaza Sur, but only a couple days to do it. The iguanas were brought back weeks later. Eleven months after the initial action, Plaza Sur is still mouse-free.

The reasons to strike quickly are two-fold: First, it's nice to take out a species over the course of, at most, several months rather than several decades. It's also much cheaper, Campbell said.

"The pilots, the boats, the people, if you had them there for several months, the bill at the end would be enormous," he said. "We have a target and we aim to implement it in as short a time as possible."

And it's time for them to move on.

"Eradication efforts on Plaza Sur [and several other islands] served as stepping stones," Campbell said. "You don't start with the largest, most complex goal, you build capacity and then move on to it."

Next year, they'll go after that target.

*****

Killing mice on an island 16 times smaller than Central Park is one thing. Killing all the mice, and all the feral cats, on an island that's three times the size of Manhattan is another. Add people to the equation, and the problem becomes much tougher.

Floreana Island, about 100 miles south of Plaza Sur and Santa Cruz, is famous for "Post Office Bay," a 200-year-old post barrel that once functioned as a mailing system for pirates. People would leave letters in a barrel, and passers-by would pick them up if they'd happen to be heading towards the addressee's location. Today, tourists keep up the tradition, visiting the barrel and helping to deliver postcards if it's convenient. The island is also home to a small, developing population of about 150 people and countless cats and rats.

Island Conservation's activities on Plaza Sur, Pinzon, and a couple other small islands, were simply warm up for what's being called "Project Floreana," a plan to exterminate invasive species on the island.

In most cities in the United States, it's hard enough to get not-in-my-backyarders to sign off on a new liquor license in their neighborhood. Try getting a small village to sign off on allowing poison to be dropped by helicopters.

"We're trying to educate them to turn some of the challenges we're facing into a 'win-win,'" Campbell said. "We have to convince them that they're the beneficiaries of this, and in their minds, they have to win."

The main goal in Floreana will be to preserve what's left of what was once one of the most magnificent ecosystems in the Galapagos. In the past several decades, Floreana's giant tortoise has gone extinct, as has a cucumber vine called Sicyos villasus. Eight other species that live on other islands in the Galapagos no longer live on Floreana. According to the Galapagos Conservancy, the island has "the highest level of species loss of any island in Galapagos." Today, it's home to nine species of endangered birds and reptiles and 32 species of endangered plants.

In order to save what's left, something will have to be done with Floreana's population during the operation. Tapia says it's likely that everyone living there will have to be relocated to Puerto Ayora, the largest city on Santa Cruz island and the entire archipelago.

"We're probably going to have to move the entire population for 2-3 weeks," Tapia said. "It's very expensive and complicated."

Among the citizens' concerns: What's going to happen to their crops during the time they're gone? What's going to happen with their pigs and cattle? How about their pet cats?

"We can't go killing other species like roosters or pigs. We're going to have to find a way to do this without putting venom in the populated areas, and we might not be able to put it in the agricultural areas either," Tapia said. "People like cats as pets, but in the long term, they're not going to be able to have them. We're not going to be able to let [house] cats escape to other parts of the island."

They've got roughly a year to figure it out. The plan is for Project Floreana to be carried out sometime in 2014, although there are still many details to be sorted. Once it's done, there'll be other things to worry about.

As a populated island, food and other goods are shipped to Floreana on a near-daily basis. With so much interaction between them and other islands, the threat of reinvasion is a very real one.

"With more traffic there's what could be considered a higher risk. Building materials are classic high-risk items," Campbell said. "But then again, now I have 150 pairs of eyes looking for this, not just one or two people at a dock investigating shipments."

As long as humans are living on Galapagos, there will be invasive species living there. The islands will never be as pristine as when human eyes first set their gazes on them. But if mankind doesn't want the giant tortoises, the blue-footed boobies, the marine iguanas replaced with field mice, wild hogs, and goats, targeted killing programs will have to continue to remain a priority.

Locals will have to buy in, forget about owning pets, pack up their stuff and move for a couple weeks. It's complicated and costly and, I'm sure, frustrating as hell to do. It goes against everything Darwin ever learned: Rats have learned to take advantage of just about every ecosystem imaginable, turtles and iguanas need everything just-perfect. But humans brought these invaders to the islands, and if anyone is going to be able to remove them, it has to be us.