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GALAPAGOS: Beach Patrols Yield Treasure Trove of Turtles |
| September 23, 2005 |
By Jennifer Jacquet, AquaNews Correspondent
 | | The telltale tracks of a green sea turtle headed for the beach under cover of night. Photo: Jennifer Jacquet |
Nowhere on Earth are Pacific green sea turtles (Chelonia mydas) more abundant than around the Galapagos Islands. There, the Charles Darwin Research Station has sent teams of volunteers to remote beaches for the past four years to study the nesting behaviour of these endangered marine reptiles.
In February, during peak nesting season, I spent ten days learning about Chelonia mydas and this comprehensive project. The following are excerpts from a few of my days of monitoring.
Day One
After riding the waves in a small, colourful wooden boat for more than three hours, we reached the white sands of Quinta Playa on the Galapagos Island of Isabela. We carried our supplies, including food and innumerable heavy tanks of water, beyond the beach and into the mangrove trees, where we set up a makeshift camp. Then, the four other volunteers and I collapsed in the heat of the midday sun to rest before our nocturnal patrol for turtles.
At 8 p.m., we headed out for more than five hours of strolling the beach. Almost immediately, we encountered the track of a female turtle that had lugged her large body ashore: sea turtle tracks resemble a one-wheeled tractor and are impossible to miss. At the end of her tracks, above the tidal zone, she was digging a nest. Her hind flippers worked like spatulas to dig a mixing bowl-size hole to incubate her eggs. The activity was methodic, instinctual, and almost robotic.
 | Fertile (left) and infertile turtle eggs, shown to scale against the point of a pencil.
Photo: Jennifer Jacquet |
Before she laid her eggs, I had a few minutes to crawl up to the musky-smelling female and observe her shell. It was, at over 80cm long and almost as wide, a testament to her many years at sea. When she finished digging, she sighed and paused. Minutes later, her tail extended and pulsated, and she began to slowly and rhythmically drop eggs. Occasionally, she dropped infertile eggs into the clutch that looked like smaller versions of the fertile, golf ball-sized eggs.
After ten minutes and 67 eggs, she was finished. Her spatula flippers worked like miniature bulldozers, quickly covering her eggs to protect them from predators. The burial took less than a minute, and during that time I checked to see if she had been previously tagged by the project. She had: her scientific name was LO 768/LO 769 (I found one tag on each front flipper, near the body). As she began to lug herself back to sea, we left to continue patrolling for four more hours and encountered 12 other nesting turtles. Each nest took about three hours from start to finish, and by the end of our busy night, I was ready for a long rest.
Day Three
 | A volunteer excavates a vacated turtle nest.
Photo: Jennifer Jacquet |
Today's task was a nest excavation. After 45-55 days of incubation, the surviving turtles hatch form their leathery eggs and migrate upwards through the sand. Twenty days later, the project excavates the vacant nest to learn more about what happens prior to hatching. Often, invading insects such as the TROX beetle burrow into the clutch and feed on the eggs. Other eggs are infected with fungus and smell, unsurprisingly, like rotten eggs. This aspect of the project also helps to account for mortality on beaches where feral pigs (with truffle-hunting noses) roam free.
Galapagos is one of the few areas of the world where turtle populations are quite healthy, but the Pacific green turtle is the only species that actually nests in the islands. One volunteer on this project previously worked on a beach in Costa Rica where she was happy to see one nesting sea turtle per night. Another Costa Rican volunteer went two weeks without seeing a single turtle.
This is not the case here on Quinta Playa: just tonight I saw seven turtles, with the added bonus of one million mosquitoes.
Day Five
 | | Aquatic garbage from parts unknown regularly washes up on remote Galapagos beaches. Photo: Jennifer Jacquet |
This morning was oven-hot. As we patrolled the beach for tracks that we may have overlooked in the night, I was daunted not only by the heat but by the amount of garbage that piles up on the shore. Although the Darwin Station turtle project cleans the beaches once a month (and studies the composition of the waste), new plastic bottles and a surprising number of shoes wash onto the beach daily.
Tonight, I watched a lava heron eat a hatchling. After about 10 minutes of dropping, picking up, dropping again, poking, and picking, the bird finally tilted back its head and swallowed the awkwardly-shaped little creature. It looked as uncomfortable as swallowing an entire potato chip - sideways. Although it was part of nature's cycle and the heron was just one of many predators, I could not stifle the feeling of wanting to save the hatchling from its fate.
 | | Jennifer Jacquet is a freelance writer and environmental economist. Her work focuses on open-access resources, particularly the dilemmas facing the marine environment. |
Day Nine
Tonight was the highlight of my visit. Around dusk, frigate birds circled and swooped in the nesting zone, hinting that there might be a birth. At first, a single, tiny half-body poked out of the sand, flippers up as if announcing the event that was about to take place. As the sun dropped further on the horizon, five more little reptilian heads appeared.
Then, at 7p.m., suddenly and like popcorn, an explosion of 60 hatchlings burst from the nest and raced to the sea. They looked like wind-up toys, their miniature flippers in overdrive, imprinting the memory of Quinta Playa on their reptilian minds. They would return to this beach years from now to lay their own eggs.
The waves overtook the hatchlings quickly and their buoyancy brought them home to the ocean. Although the perils of the sea are vast, hopefully one of those babies will live to a ripe adulthood of 50 years or more.
| Source: Vancouver Aquarium Marine Science Centre |
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