A report by Elisabeth Malkin and Paulina Villegas for The New York Times.
The day-trippers swarmed onto the beach to watch one of nature’s most extraordinary sights, hundreds of thousands of olive ridley sea turtles crawling out of the ocean to lay their eggs in the sand.
The turtles did not want the company. Scared off by the thousands of tourists massed along Ostional Beach on Costa Rica’s Pacific Coast, snapping selfies and perching their children on the turtles’ backs, the ancient reptiles simply turned around and retreated into the sea.
“It was a mess,” said Yamileth Baltodano, a tour guide who was at the scene when the turtles were scared away two weeks ago.
What happened during the first weekend in September was a one-time event, when a confluence of factors allowed the utterly unexpected to take place. But it was a cautionary tale for the conservationists charged with protecting the turtles, which are classified as vulnerable, not to mention a social media sensation. Now Costa Rican officials are scrambling to make sure it does not happen again.
“We are reassessing the way we work and the way we tackle the issue,” Mauricio Méndez, deputy director of the Tempisque Conservation Area, which includes Ostional Beach, said in a telephone interview on Friday.
The olive ridley nesting season, from August through October, coincides with Costa Rica’s rainy season, which ordinarily provides a natural barrier that protects the turtles. During that time, the beach is all but cut off by the flood tide of the swollen Nosara River, which blocks access on bridges. Even in the dry season, the beach is accessible only by a four-wheel-drive vehicle driven by a local guide.
But this year, low rainfall caused by El Niño left the river all but dry, making passage to the beach easy.
Mr. Méndez said officials were working on changes before the next arrival, expected on Oct. 4. He said he hoped to double the number of police officers and security guards, and even to bring in the Coast Guard. Groups will be allowed in only with guides and will be limited to the edges of the nesting area.
Despite the commotion, turtles still managed to lay some eggs, perhaps at night. Mr. Méndez and his team found many more eggs than they expected after the frolicking tourists went home.
“A tornado can be happening, and they will continue to deposit the eggs, carve it out, nest, and go back to sea,” he said.
The turtles, which lay their eggs during a three- to four-day period each month, began to arrive early on Sept. 4. Photographs of the phenomenon quickly began to spread on social media.
From a distance, aboard a boat, Vanessa Bézy, a sea turtle biologist, watched in dismay as hordes of tourists clogged the beach, overwhelming the guards.
“I almost had a panic attack because it was so crowded,” said Ms. Bézy, a doctoral candidate at the University of North Carolina at Chapel Hill, who has been studying nesting behavior at Ostional Beach for five years. “It was basically a free-for-all.”