Las Baulas National Marine Park

Picture the beach at night. The moon is low over the water. The sand is dark and cool. Then, out of the black sea, a huge shape rises. It is a leatherback turtle, larger than a person, dragging herself ashore to lay her eggs. This is the sight that Las Baulas National Marine Park exists to protect.

The park takes its name from the turtle. In Costa Rica, the leatherback is called the baula. It is the largest sea turtle in the world. In fact, it is the largest living reptile of any kind. The biggest ones can weigh more than 900 kilograms. Unlike other sea turtles, it has no hard shell. Instead, its back is covered with tough, leathery skin and seven long ridges. That is how it earned its name. These animals have swum the oceans since the age of the dinosaurs.

Las Baulas National Marine Park sits on the Pacific coast of Guanacaste. It was established as a national park in 1991, after years of work by scientists and conservationists. They had shown how important this coast was for the survival of the leatherback. The protection came in time to slow the loss.

The park is larger than it first appears. On land it covers about 167 hectares. At sea it reaches across roughly 22,000 hectares of water. It protects several beaches, including Playa Grande, Playa Ventanas, Playa Carbon, and Playa Langosta. It also takes in the Tamarindo Estuary and its mangroves. Together, that is a large stretch of ocean and shore to watch over.

The heart of the park is Playa Grande. For thousands of years, leatherback turtles have come back to this beach to nest. A female turtle hatched here will swim across the ocean for decades. Then she returns to the same shore where her own life began, to lay the next generation.

The nesting season runs mainly from October to February. The turtles come at night. A mother turtle climbs the beach, digs a deep nest with her back flippers, and lays her eggs. Then she covers them with sand and returns to the sea. She never sees her young.

About two months later, the hatchlings break out. They are tiny and dark. They dig up through the sand, usually at night, and rush toward the brightest horizon, which is the open sea. Very few of them will live to grow up. Crabs, birds, and fish wait for them along the way. The short dash from the nest to the water is one of the most dangerous journeys in nature. The ones that do survive may not return for many years.

Watching this is a careful act. Visits to see the turtles happen only with trained local guides. The number of people is limited. Bright lights and flash cameras are not allowed, because light confuses the turtles. The rules can feel strict. They exist because the eastern Pacific leatherback is in serious danger.

The threats are real and many. For years, people took turtle eggs from the beach. Fishing nets out at sea can trap and drown adult turtles. Building and bright lights along the coast disturb the nesting beaches. The park is one line of defense against all of these. Today, teams of biologists patrol the beach through the night during the season.

If you want to see a nesting turtle, plan ahead. Tours run during the nesting season and must be booked in advance. A guide leads small groups onto the beach and waits, often for a long time, until a turtle comes ashore. Patience is a large part of the experience.

The park is worth seeing in daylight too. Playa Grande is a long, open beach with strong surf. Behind it lie dry forest and wetland. Birds move through the mangroves. The same beach that hosts the turtles at night is a quiet, wide shore by day. Surfers know Playa Grande well for its steady waves. By day it belongs to the board riders. By night it belongs to the turtles.

Stand on Playa Grande in the late afternoon. The wind comes off the sea. The waves are loud and steady. The sand runs far in both directions, with few buildings in sight. It is easy to imagine the beach exactly as it was long before any town grew nearby.

Las Baulas protects something we cannot make again. The leatherback has lived on Earth for over a hundred million years. Whether it survives the next hundred depends partly on beaches like this one. Each protected nest is a small bet on the future. When you stand here quietly and follow the rules, you join that long, slow effort to keep it alive.