This article is from the Winter 2009 Defenders of Wildlife magazine. To learn more about sea turtles and the conservation work Defenders of Wildlife is doing, please visit http://www.defenders.org/. My little ocean buddies need all the help they can get so spread the word.
Sea turtles drown by the hundreds every fishing season in Baja, California—but it doesn't have to be that way by Heidi Ridgley
Discovering your life's calling seldom happens with a "Eureka!" moment. But when a 300-pound adult male sea turtle tried to mount Hoyt Peckham while he was underwater filming humpbacks in the South Pacific, the biologist took it as a sign from above—or, in this case, from behind.
"He hit me so hard, I thought, 'This is it—a big shark's got me and it's all over,'" recalls Peckham.
Turns out he—not the turtle, which quickly realized his faux pas—was the one with the date with destiny that afternoon. "Local islanders had been asking me, 'why don't you help us save our turtles instead?' I hadn't given the idea much thought until this turtle demanded my attention," he says.
Almost a decade later and thousands of miles away in Mexico, he is standing on the stern of a small open skiff—called a panga—moving swiftly off the shores of Baja California Sur. Peckham, now director of field research at the binational nonprofit ProPeninsula, is heading toward the zona caguamera—the turtle zone—a hotspot for juvenile loggerheads in the Pacific. In these nutrient-rich waters, loggerheads feed for 35 years—it takes that long for them to reach reproductive age—before they ride ocean currents back to the Japanese shores where they hatched to mate and lay eggs of their own. The problem is that fishing boats also ply these waters and as a result, a catastrophic number of loggerheads, thought to be the world's largest hard-shell turtle, accidentally get caught and drown in fishing nets or die hooked on longline fishing gear.
The blame for sea turtle deaths often falls on fleets of industrial-sized fishing trawlers, like those near Hawaii, where another population of loggerheads spends its juvenile years. But in Mexico, Peckham and his colleagues have found that the cause is exactly the opposite. Local village fishermen in tiny boats with outboard engines kill an estimated 1,500 to 2,000 loggerheads while hand-fishing with longlines and gillnets each season. By contrast, the industrial longline fleets of the Pacific—including those of the United States, Australia, China, Japan and Portugal—kill a total of 1,400 sea turtles a year.
Seeing washed up carcasses was not something Peckham anticipated when he arrived on the Baja peninsula in 2001 to study the turtles—as a biology graduate student at the University of California-Santa Cruz. He also didn't expect he would end up leading a crusade to save them. But that's exactly what has happened.
"I came here to figure out why loggerheads spend so much time here," he says. "I set out to focus on turtle ecology, but I soon realized I couldn't just ignore the by-catch problem. There was no way I could study the nuances of the animals while watching them die. I had to figure out how I could make a difference."
Two bottlenose dolphins swim beside the panga as we make our way into the open ocean on this summer morning. Today's goal is to draw blood from as many turtles as can be caught, with the ultimate goal of getting samples from 25 loggerheads in the coming weeks. If the lab results show the turtles are healthy, as Peckham expects, this will help him refute arguments from local officials that an epidemic may be behind the large numbers of dead turtles washing ashore. "We don't think disease plays a big role because the strandings happen every year at the same time—just when fishing season starts," he says.
The sand dunes we pass along the shore soon give way to mangroves overflowing with nesting frigate birds and cormorants. Then, there is only water as far as the eye can see. We have entered the zone—50 square miles where we will zigzag back and forth all day in the blazing Baja sun, looking for irregular bumps on the surface. As cold-blooded reptiles, sea turtles surface periodically not only to breathe but also to bask in the sun's warmth.
The first creature we encounter here, however, is a sea robin—a small boney fish with no commercial value for fishermen—that floats dead on the surface. When the boat slows, Peckham leans over the side and scoops it up with his hand. "Eighty-eight percent of the loggerheads we do necropsies on have these fish in their stomach," he says, pointing to a gill net—made from very fine mesh—strung a half mile from one buoy to another ahead of us. Although sea turtles normally dine on crustaceans and jellyfish, loggerheads are more likely to eat discarded dead fish for reasons yet unknown and this exacerbates their propensity to get caught in the gillnets. "I think it may just be a case of curiosity killing the cat," Peckham says. "And it's the opposite of what we are used to seeing in the wild—usually scavenger species fare better than others in the face of human activities."
The water is rough, and the choppy surface will make it hard to spot floating turtles. "Our record sighting was from 1.4 kilometers [almost a mile] away but today finding them will take more luck and patience than good eyes," says Peckham, using a taut rope to steady himself as he stands on the bow of the boat. A moment later he goes quiet, motions for the captain to accelerate and dives off the side and after a turtle. It seems at least a minute goes by before his head re-emerges. He is all smiles. The fins-flapping turtle he is holding half out of the water is not nearly as amused.
Once the turtle is heaved aboard the boat, the medical team goes to work. Blood is drawn and the turtle is tagged, weighed (this one is 77 pounds) and scraped free of mussels, barnacles and algae. "It makes them slow," Peckham explains, flicking a tiny crab into the sea. "They really carry an ecosystem on their backs, providing habitat in the open ocean." In fact, this turtle's shell is what gave him away. "I spotted it because I saw fish flashing underneath the water," he says. "A school of yellowtail was feeding around the turtle—probably even off its shell."
After the turtle is gently slipped back into the sea, a full three hours pass before biologist Vladimir de la Toba, from one of the local towns, spots the next one, launches himself overboard, nabs it underwater, steers it upward and holds it up to the others who lug it aboard by the flippers. This one is so covered in algae, it looks like a moss-covered stone in an old-growth forest. While the medical team goes to work, de la Toba lays beside the turtle picking crabs off the shell, while another researcher scrapes off the algae.
The last turtle brought aboard later in the day won't return alive. Voluntarily handed over by local fishermen, it had just drowned in a net. Turtles can hold their breath for about five hours underwater, but not if they're stressed. Then death can come in as little as a half-hour.
On shore, a necropsy shows this turtle was well-fed and healthy. Peckham, who has pulled me to the side, already assumed as much: "The science is already in," he says. "You can cut up a different dead turtle and come up with 50 questions about its biology every time and they'd all be really interesting, valid questions, but we already know what we need to do to protect these turtles. To save them, it's now a matter of political will."
To encourage such action, Peckham partnered with local fishermen to catalog the dead turtles that wash ashore here. Stretching 30 isolated miles, this ocean beach just downwind and down current from the turtle hotspot sees an average of 475 turtle carcasses washed ashore a year—90 percent during the four summer months that coincide with gillnetting, and 95 percent of the turtles are loggerheads. At about one loggerhead every two miles, every day and all summer long, it's the highest worldwide stranding rate ever recorded. On our patrol of the beach the next day, we count four new carcasses that get spray painted and dragged beyond the tide line. "My first summer here in 2002, I was totally unprepared to see so many dead turtles—it was devastating, really," he says. "We reported the data to fishermen and authorities in La Paz but they asked us, 'How do we know you're not making this up?' So we thought, 'We'll just have to prove there's more than one turtle.'"
They selected a spot on the beach to collect all the carcasses and just a few years later some 500 shells and skulls protrude from the sand—at most a quarter of the carcasses that have washed ashore here after drowning in nets and then being thrown overboard. "If you were a fisherman driving this beach in the past, you might have seen one or two a day and not thought much of it—and assumed they were the same carcasses every time," says Peckham. This graveyard paints a more accurate picture. The worst part, says Peckham, is that not one of these turtles—which by their sizes range in ages from 20 to 40—will have reproduced. "Their lives were totally wasted—a total of 15,000 turtle years here, all fruitless."
And those are still just a small portion of the dead. Only a handful of every dozen that are caught and discarded locally ever wash ashore. The rest are carried away by currents or scavenged in the sea. Peckham and his team have tagged many dozens of dead and bloated turtles that come floating past his boat over the years. Of those tagged, very few have ever washed up to rank among the counted.
But as a result of his actions and those of a coalition of groups—including Defenders of Wildlife's Mexico office—in partnership with local fishermen, much progress has been made, including work toward establishing a refuge of Baja's turtle hotspot. Relying on legal protection in this part of Mexico is hard—the peninsula has thousands of miles of lonely coasts and only a few people to police it. "In the United States, it's worked okay to close fisheries," says Peckham. "But to do that you have to have the resources. There are also social and cultural costs when you shut down a way of life."
Peckham, along with colleagues from the Mexican nonprofit Grupo Tortuguero, developed a different approach: connecting with community leaders and local opinion leaders by inviting them to go offshore to catch a turtle, which they show to their kids, who name it—usually after their mom—and see a transmitter get attached before it's released. Their kids can then track it over the Internet. Too often, however, the turtle only makes it a few days—which is what happened to the governor's turtle recently. In town a few days earlier to dedicate a new pier, the governor drove the point home in dramatic style by calling on Peckham to break the news to the crowd about his turtle, which drowned only 11 days after tagging.
Because Peckham and his team couldn't put a transmitter on every turtle—or take out every fisherman in Baja—he connected to fishermen by convening workshops beginning in 2003 to help them understand the global impact of their local by-catch. "All agreed they killed a few a week, no question," says Peckham. "We started a process for them to come up with their own solutions, including testing different hooks, net types and sizes, and avoiding turtle high-use areas."
Peckham also received a grant from the U.S. Fish and Wildlife Service to take a few local fishermen to the loggerheads' nesting grounds in Japan. As part of a tri-national exchange that included fishermen from Hawaii, they met local Japanese fishermen who told them how teeming the nesting beaches had been when they were young—Japan's turtle-nesting rate has declined 50 percent to 80 percent across the archipelago. In fact, one beach where 800 nesters were recorded in 1960 saw only one nester in 2000.
As a result of this trip, Efrain de la Paz, one of the most proficient fishermen on the peninsula with a small fleet in the Baja village of Santa Rosa retired his lethal longline fishing gear in 2007—after setting them in Baja waters since 1985—agreeing to use alternate gear. "It became a matter of pride for him: He was embarrassed they were killing more loggerheads than anyone else we know of and that it was so drastically affecting loggerheads back on their nesting grounds in Japan," says Peckham. "His commitment saved 1,000 turtles alone."
With only one in 1,000 loggerheads reaching reproductive age, each juvenile saved is of incredible value to the future population. "Facilitating de la Paz's transformation may have been the greatest contribution of my career," says Peckham. "But it's not my goal to make everyone a turtle lover. It's to help people become better stewards of our oceans."
Sunday, February 8, 2009
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