California Wild Summer 2005 - In Pursuit of Science

The Magazine of the CALIFORNIA ACADEMY OF SCIENCES

In Pursuit of Science

Lessons in Leatherbacks

Dave Brian Butvill

As dawn breaks on a deserted Caribbean beach in northern Costa Rica, a bouncy American beachcomber named Lily Coble drops to her knees and plunges her hands into the ash-colored earth. She digs one, two, now three feet down, and pulls out her treasure: a rotting baby sea turtle the size of a Twinkie. Its head and front flippers dangle lifelessly from a torn, rubbery eggshell coated in slime.

"This one almost made it," she says, and tosses the tiny corpse aside. She then extracts three hatchlings barely alive enough to lift their heads. After only a few minutes in the fresh air, the turtle trio shuffles toward the shore and is swept out to sea.

Coble, who just graduated from high school, came all the way from Polson, Montana, to help scientists study and protect critically endangered leatherback sea turtles. Documenting turtle nesting success by day, she spends the night scaring off egg thieves, the number one threat to leatherback survival in Costa Rica. The data she collects on mother turtles will be used by scientists in many countries to save even more hatchlings in the future.

It's all part of an intense twelve-day boot camp run by Ecology Project International (EPI). The project pairs high school and college students from Costa Rica and the United States with struggling species in the Americas for a new kind of education. "We're not out to create a bunch of scientists," says EPI cofounder Julie Osborn. "We want people to experience ecology. Then they will really feel their impact on the world."

In the process, scientists get loads of data. Turtles get saved. And for many participants, lives get changed. "I was thinking about becoming an English major," Coble says. "But nope. I'm going to be a biologist."

The students are working to protect this remote stretch of beach in Pacuare Nature Reserve from local hueveros, or egg thieves. The area is a primary leatherback nesting site. As night falls, the hueveros will paddle past crocodiles and caiman, and slog through rainforest muck, to collect the local delicacies.

I've come to help the current recruits, a couple of dozen students mostly from Bishop O'Dowd High in Oakland, California, save turtle eggs from becoming bar snacks at the local cantina. Tonight will be my first beach patrol. The students have done this three times over the past week and are already seasoned turtle trackers. They've been trained in data collection techniques and have received lectures on leatherback biology and behavior from local scientists.

They've also devised their own research projects. Some are evaluating the relationship between the size of a mother's rear flipper and the depth of her nest, for example, while others are determining whether larger turtles nest farther up the beach.

Come sundown, I meet preserve biologist Belinda Dick and Sophia Bickford, EPI's lead instructor. Bickford's been living out of a cabin without electricity for the past three months, "some configuration of beans and rice" her daily fuel. She briefs me on the patrols: Troops of four or five students, led by local experts, will monitor the two-mile stretch of nesting beach until dawn. We cover our flashlights in red cellophane to avoid scaring off any turtles; turtles can't see red light. Our group will be back in four hours if we're lucky.

We set out into the moonless night. The sting of the daytime sun is gone, but the air still feels thick enough to cut with a machete. I ask Bickford about the poachers. "They're people from the city trying to make a few extra bucks-often to support a drug habit. None of them do it for subsistence," she says. Indeed, an investigation by Pacuare staff revealed that the thieves used the turtle eggs more or less as credit at bars, or to buy drugs.

Biologist Dick is quick to add that there's never any trouble. The hueveros are always outnumbered by students, and don't risk getting busted. "Here, poachers hide from us. It's whoever gets to the turtle first."

As if on cue, local guide José Gerardo Zoniga points out the unmistakable tracks of a poacher. "They leave flat markings, because they don't wear shoes," he says, pointing to the telltale depressions in the sand. "It's easier that way to escape through the mud of the forest."

We follow the tracks for about a mile, when a student spots a giant dome glistening in the crashing surf. There's no mistaking a leatherback. The largest of all sea turtles, baulas, as they're known locally, may grow up to seven feet long with twelve-foot flipper spans. The largest resemble Volkswagen bugs as they emerge from the deep.

We watch from a distance as she plods through the same routine her ancestors followed a hundred million years ago-pushing forward, looking around, sighing, and pushing forward some more. Finally she reaches dry sand, excavates a pit several feet deep, and starts laying dozens of round white eggs. Only then does our team mobilize, taking advantage of the trancelike state turtles enter when laying.

At about five feet long, the turtle is relatively small, yet it still takes two students to measure her leathery shell. Others record her tag numbers and a dozen more data points, including any injuries on the turtle, and the number of eggs she lays.

Because of the wandering poacher, student Alissa Petrites bags about a hundred lemon-sized eggs and disappears into the darkness to dig a second nest. She goes alone to be stealthy, stepping only on seaweed to make her path untraceable. "It was kind of freaky out there on the beach by myself digging this nest," she reports later. "I was really worried I'd see the poacher in the woods. But I did it-I saved her babies." After reburying the eggs, and erasing any signs of their presence from the sand, Petrites noted the new nest location for future monitoring.

In about nine weeks, the hatchlings will dig their way to the surface together. Soon afterward, Pacuare staff and students will dig up what's left to gauge hatching success and turtle fertility, the way Lily did earlier in the day. "The stinky part is opening up the eggs that don't hatch," says Lily. However, unhatched eggs provide clues which could prove critical to leatherback conservation. "A batch of eggs without embryos, for example, might indicate a problem in the environment-be it contamination in the sand or the mother." Luckily, it's not a common problem on this beach.

All of the student researchers' data will eventually be sent to the Archie Carr Center for Sea Turtle Research in Gainesville, Florida. There, it will be added to a database used by sea turtle researchers. "The scientists were extremely skeptical at first," Bickford says of EPI's work. "Now they welcome our data with open arms."

After a thrilling hour-long operation, we pause, satisfied that the nest is now safe and all the critical data has been collected. Caked in sand and sweat, we watch the mother-to-be shove off into the black ocean. We finish the patrol and arrive back at headquarters around two in the morning, happy not to be one of the groups out until dawn.

"Sea turtles are international animals, and effective conservation requires an international effort," says Scott Pankratz, who founded EPI along with Osborn in 2000. Locals make up roughly two-thirds of EPI's annual participants-some 500 students who occupy the beach every day during the three-month leatherback nesting period that begins in March.

"Because practically none [of the U.S. students] spoke Spanish, it was a bit difficult to communicate," says 17-year-old Diurno student Kendall Araya Ramos. "But what was strange is that we understood each other, maybe because we were united for the same reason-the love of nature." Ramos adds that meeting his U.S. counterparts also cultivated a sense of mutual trust and respect. "They demonstrated their commitment and enthusiasm to us, and showed that they weren't phonies."

Meeting "helps the students recognize their similarities, their common struggles, and their common abilities to make a difference, even though they live so many thousands of miles apart," says Pankratz. "It's how science happens the world over."

In addition to the turtle work, all participants conduct biological surveys in rainforests and banana plantations, and plant trees to help expand one of Costa Rica's national parks. At Pacuare, in addition to guarding turtles, they've removed washed-up logs to make life easier for nesting mothers and their future hatchlings, and picked up dozens of pounds of garbage to keep the beach pristine. The connection between throwing a candy wrapper out the car window and the health of leatherbacks sinks in.

For Ramos, working with turtles at Pacuare was both exhilarating and difficult. "When I was a kid, I used to accompany my dad and other people to the beach, where they were in search of eggs-and if they were lucky, they would catch a turtle. One time, I saw them kill one in my own house," he explains. "So I liked having had the opportunity to help the turtles after having treated them so badly, to correct my errors."

Dave Brian Butvill is a science writer based in Coast Rica.