The Turtle Trackers
In the Pacific Ocean's remote Arnavon Islands, a project to help endangered sea turtles is unlocking the mysteries of migration.
Spring 2017
Mama Kawaki isn't fond of walls. In a makeshift pen beneath palm trees on Kerehikapa Island, the turtle repeatedly butts her head against the sideboards, trying to knock them down.
Wearing sand-caked flip-flops and board shorts, Rick Hamilton looks on at the 4-foot-long, 150-pound turtle with admiration. “That is the biggest, feistiest hawksbill I’ve ever seen,” he says. “She’s awesome.”
They make an odd pair. Hamilton is the marine scientist who heads The Nature Conservancy’s Melanesia program. Sporting a scruffy look and on-again, off-again reading glasses, the Brisbane-based scientist seems part geeky researcher, part Aussie gator wrestler. Mama Kawaki, probably in her 40s, appears ancient. She is full of eggs and ready to nest.
Named for their hooked beak, hawksbill turtles are renowned for their color-splashed shells, which have long fed the global demand for “tortoiseshell.” Hawksbills live throughout tropical waters worldwide, but those around here are very loyal to a remote quartet of islands called the Arnavons.
The Arnavons lie near the western end of the Solomon Islands archipelago, a volcanic chain of more than 900 islands strung out across nearly 1,000 miles of the South Pacific. Nearby islands are dotted with dense villages of stilt houses, but except for a handful of rangers, the Arnavons themselves are uninhabited. With their hardy reefs and relatively protected beaches, the islands are the hawksbills’ prime breeding ground: More females haul out here to lay eggs than anywhere else in the South Pacific.
“It’s truly a paradise for these animals,” Hamilton says. “We just want to keep it that way.”
Historically, however, humans have not been kind to hawksbills. The turtles are a traditional part of the diet and ceremonies of people here, but they have also long been a source of easy cash. Beginning in the 1800s, islanders slaughtered hawksbills en masse with spears and sold the shells to foreign traders to make art and jewelry.
Today, hawksbills are listed by the International Union for Conservation of Nature (IUCN) as critically endangered. Fishing boats and nesting habitat degradation have taken a toll. And despite legal protection, commercial poaching continues; even young turtles are killed, stuffed and sold as curios. “Honestly,” Hamilton says, “I’m surprised there are any left at all.”
Yet there is hope. Thanks to a series of conservation efforts in the 1990s, hawksbills are rebounding. Hamilton has arrived here with 10 satellite tracking tags, on a quest to learn more about the hawksbills’ nesting behavior, where they go after they leave the Arnavons and why some wait as long as seven years between nesting seasons.
In just a few hours, the team will release Mama Kawaki with one of those tags affixed to her carapace. What it reveals about her nesting, migration and foraging habits will help shape stronger conservation strategies for these poorly understood animals. Says Hamilton, “We have a lot to learn.”
A British protectorate since 1893, the Solomon Islands—a group of six major islands—were occupied by the Japanese during World War II and were the site of bitter battles, including Guadalcanal. The nation achieved self-governance in 1976 and independence two years later. The new government declared the Arnavons a hawksbill sanctuary.
But traditional hunters struck back: In 1982, a villager named Rence Zama burned down a government field station. Emboldened, hunters sharpened their spears, and by the late 1980s the annual take had risen to more than 4,000 turtles.
TNC arrived around the same time. By 1995, the organization had helped establish the nearly 40,000-acre Arnavon Community Marine Conservation Area. A national ban on trading turtle products followed.
And sentiment here has shifted. Today, Zama—who served three years in jail for the arson—is a member of the board that oversees the marine conservation area. “I have changed my thinking,” he says. “I was a hunter. But now we must make sure the turtles are still here for the next generation.”
Except for the hours that females go ashore to nest, hawksbills spend their entire lives at sea. They face a torrent of threats. Birds, crabs and other predators snap up many hatchlings as they race from their nests to the ocean’s edge. And the water is no haven from birds above or reef sharks below.
During their first years of life, “the hatchlings are very small and very vulnerable,” floating where the currents take them, Hamilton says. “As few as one per thousand makes it to maturity and returns to nest.” That can take up to 35 years.
But hawksbills have been getting help. Local rangers trained by TNC find and mark nests, protect the eggs from predation by birds and relocate nests above the high-tide line if necessary. They also help hatchlings scramble down the coral-strewn sand to the sea. Perhaps most important, they deter poachers out to kill nesting females on the beaches.
Those efforts have made a big difference. “Since the marine conservation area was established, the number of nests in the Arnavons has doubled” to more than 1,200 a year, Hamilton says. And “while their populations are still well below historic highs,” he says, “there are enough around to teach us a lot about hawksbill population dynamics and migrations.”
That’s what led Hamilton to show up with a case full of satellite tracking tags last summer.
Mama Kawaki, named after a TNC-supported group that boosts women’s role in natural resource decision-making, will be one of Hamilton’s 10 trailblazers. Rangers caught her on Sikopo as she sought a nesting spot and quickly boated her to Kerehikapa.
Here, they lug her to shore to be measured and fitted with a satellite tag. One ranger holds a rag over Mama Kawaki’s eyes and massages her neck. Another wipes dirt from her carapace, exposing its rich colors, and sands a fist-sized area. Hamilton brushes strong epoxy over fiberglass mesh to affix the one-pound tracking device, which resembles a restaurant pager with an antenna.
Each time she surfaces to breathe, the tag will transmit her location to an orbiting satellite; Hamilton can then use that information to build detailed migration maps.
Funded by private donors mostly from Hong Kong and the United States, the project has several aims: to better understand hawksbill nesting, migration and foraging patterns; to boost education in the Solomons and around the world about the hawksbills’ plight; and to determine the effectiveness of current protected areas.
Hamilton taps the tag on Mama Kawaki’s back. “We’ll have a window on hawksbills that was shut tightly before,” he says. “I can’t wait to see inside their world.”
While hawksbills are endangered, it is legal to kill them for subsistence and ceremony. “Some 85% of people in the Solomons live on a subsistence basis, and their main resource is the sea,” Hamilton says. “Turtles remain an important food for feasts. It’s not just for the protein—it’s part of the cultural heritage.”
But awareness is growing that even noncommercial hunting takes a toll. “We have a lot of other things to eat, like potatoes and pigs,” says Moira Dasipio of Kia. “Yes, we eat turtles for ceremony, but now we know turtles are important to the oceans. We won’t starve if we leave the hawksbills alone. We need to question ourselves and our traditions.”
Poachers continue to feed the market. Significant numbers of hawksbills also die far out at sea, tangled in nets or caught on longline hooks set by commercial fishing boats.
Another threat is mining, which promises desperately needed revenue for the Solomon Islands but could also harm hawksbills. The now-closed Gold Ridge mine on Guadalcanal provided as much as 30% of the nation’s gross domestic product. Last year, however, a toxic waste pond overflowed, raising fears of habitat damage./p>
In response to newly proposed mines, TNC helped organize the Solomon Islands’ first National Mining Forum. “People need to understand the long-term nature of this industry and make sure the government and mining companies are accountable from the start,” says TNC’s Melanesia conservation director, Robyn James. “Otherwise, they will bear the impacts and not see the benefits.”
TNC is also working to strengthen anti-poaching enforcement and develop alternative local livelihoods. Seaweed harvesting has become profitable for the Wagina community, and the women of KAWAKI are stepping up to manage ecotourism. Already, cruise ships are stopping by the Arnavons, and several groups have come to visit turtle nesting beaches.
On the beach at Kerehikapa Island, some six hours after Hamilton’s team mounted the transmitter on Mama Kawaki, it’s time to set her free. Six women carry her into the water. When they are waist-deep, skirts floating like petals round them, they open their hands. Mama Kawaki swims out of sight as a sweet soprano voice rises, one of the women improvising a farewell song.
Hamilton’s team tag and release nine more turtles. Two weeks later, one of the satellite transmitters goes silent. Not long after, a second stops sending signals.
Back in Brisbane, Hamilton soon gets the news he has been dreading. One night when rangers were away, poachers had boated to Sikopo and speared two tagged females nesting there. To avoid being tracked, the poachers hacked off the satellite tags and tossed them into the ocean.
“When I first heard, I was so angry and disappointed that I couldn’t talk about it,” Hamilton says. “It felt like a failure, a real kick in the gut.”
But the survivors have helped him peer deeper into their lives. Hamilton was glued to his laptop for months, watching the turtles’ journeys unfold.
One tagged hawksbill stayed near the Arnavons. The rest traveled more than 1,200 miles to the Great Barrier Reef, swimming more than 30 miles per day. Hamilton says the tags revealed that once they make it to their destinations, “hawksbills are homebodies, really tightly tied to specific reefs.”
The satellite data have also confirmed that existing protection strategies are sound. Hawksbills are migrating between the Arnavons marine conservation area and protected foraging grounds on the Great Barrier Reef, so they’re spending most of their lives in relatively safe waters.
Still, Hamilton’s research highlights the need for a broader perspective on hawksbills. “Because of their long migrations, turtles require international collaboration,” he says. “If they go to Australia and Papua New Guinea and the Solomon Islands, we need to reach across the water for conservation to work.” Last August in Australia, Hamilton spoke at a workshop that kicked off discussions about multinational conservation efforts.
But another threat is developing: climate change. Because trade winds push water into the western Pacific, the sea in the Solomons is rising at more than double the global average—and gobbling up the turtles’ nesting beaches. By 2016, five reef islands in the region had disappeared. Six more are vanishing.
For now, hawksbills may survive simply by finding higher ground. But “what will happen as their beaches disappear completely?” Hamilton says. “We just don’t know.”
This is still a perilous time for hawksbills, but the animals have proven themselves survivors. And with Solomon Islanders taking on an ever-growing role in conservation, Hamilton says, “I think these animals have a heck of a chance at survival.”
Meanwhile, headstrong Mama Kawaki has become a mystery. She seems to have laid eggs on Kerehikapa soon after her release, and she buried another clutch two weeks later on Sikopo. After that, she began swimming toward the great Barrier Reef. On May 26 last year, hers became the third satellite tag to stop transmitting. By that point, however, she was about 100 miles off the northern Great Barrier Reef, where poaching is extremely unlikely: Hamilton believes her tag simply fell off.
Hamilton may never cross paths with Mama Kawaki again, but he is about to enlist a new cohort of scientific pioneers. This year, he will return to the Arnavons to tag another 10 turtles, followed by 10 more in 2018. In the meantime, Mama Kawaki’s seven fellow travelers continue to draw lines on Hamilton’s map that will help save their kind from extinction.