The Half Million Sea Turtle Crawl

Olive Ridley Sea Turtles emerging from the water en masse during an arribada at Ostional Beach. Photo courtesy of thesasupost.wordpress.com Time your trip to Costa Rica right and you will have an opportunity to see one of the most magnificent wonders of the natural world--the arribadas at Ostional. During Arribadas, hundreds of thousands of turtles will come to lay their eggs on the beach. Four times a year, ten days before the new moon from August to November, masses of olive ridley sea turtles simultaneously swim out of the sea and lay millions of turtle eggs on the beach. So many turtles come that the later turtles destroy the nests of the earlier turtles. In fact, sea turtle egg harvesting is legal during the first few days as a way to support the local economy, since the beach can't physically accommodate all of the eggs that are there.

Locals ("Ticos") have a genuine admiration and astonishment for the abundance of wildlife in Costa Rica. My surf instructor recounted the morning snorkeling excursion he led. They went out in a boat (much farther than we kayaked) and spotted "about 600" dolphins on the move. "You can never predict it, it's nature," he told me. We also encountered nocturnal wildlife. In Playa Carillo, crabs braved their lives to cross the road near the beach to make it to the sandy area where they would lay their eggs. As we drove along the beach in the evenings, the large crabs would stop in the middle of the road and stare at our Toyota's headlights before scurrying back to safety. Many crabs were not so lucky, evidenced by the flattened crabs we would find along the road by the beach during daylight.

But the most fascinating of the wildlife we encountered were the nesting olive ridley sea turtles in nearby Playa Camaronal in Guanacaste.  We didn't get to see an arribada, but we did venture on a late night tour with a guide/conservationist.  We were careful to make little noise, and we refrained from using bright lights, as that would frighten the sea turtles and cause them to return to the water for a few hours before attempting to nest again.  The turtles were easy to find--there would be a straight line of turtle tracks coming from the sea, and eventually, they stop somewhere and start to dig their nest.  Like other reptiles, the depth of the nest determines its temperature, which determines whether or not the eggs will mature into males or females. Once the turtle is satisfied with her nest, she goes into a trance, using every ounce of energy and concentration to lay her eggs.  The species we encountered lays about 100 eggs in each nest. Although, only a fraction of these eggs reach adulthood--due to both natural and manmade threats (including poachers, and getting caught and drowning in fishing nets).

Olive Ridley Sea Turtle nesting

Look closely and you can spot the ping pong-shaped eggs.

Watching a sea turtle drop ping pong ball-sized egg after egg was incredible.  The eggs seemed to ooze out, covered in a slimy substance.  Once the turtle finished, she then used her limbs and body to pack sand over the eggs, and proceeded in a dance-like, thumping movement to pound the sand down and then camouflage the area, before making her slow and labored trek (in a straight line) back to the ocean. Although these turtles lay eggs nightly during nesting season, they also nest en masse during "arribadas" at places like Ostional.  Our guide spoke of the arribadas with reverence and awe. "There are so many turtles, you can hardly walk around them," he told us. One year, as many as 500,000 sea turtles came to Ostional beach to lay eggs during a single week. "It's amazing," he said, eyes aglow. "But there are less and less each year."

Conservation Efforts

Our guide  then told us about how students at local schools in the area watch the nests, and when the eggs hatch, they ensure that the sea turtles safely make their way to the water.  Removing the eggs isn't an option since sea turtles return to the beach where they were hatched in order to nest. If the eggs were removed for "safekeeping," the turtle would not know what beach to return to--which is especially important since these swimmers migrate over a thousand miles between their feeding and nesting grounds. But, I'm convinced that the most important thing that we can do to ensure that these ancient creatures don't become extinct is to support sustainable food practices and not continue to drain the earth of its resources.  Sustainable food practices are so important, as many sea turtles drown after being caught in fishing nets.  How can sea turtles drown? Well, they can hold their breath for up to seven hours--unless they are under distress.  If they are under distress, they can only hold their breath minutes--meaning by the time someone realizes they've caught a sea turtle in a giant net, it will be too late.

Baby olive ridley sea turtles digging their way out of the nest--it can take them up to a week to dig themselves out!