Las Baulas de Guanacaste Marine National Park is a National Park of Costa Rica and a Ramsar Site. The park is managed by the Tempisque Conservation Area, and covers approximately a 167.3 square kilometres marine area of the Tamarindo Bay, next to the town of Tamarindo. It supports the largest nesting colony of leatherback sea turtles on the Pacific coast of the Americas. Female leatherbacks often come ashore at Playa Grande between October and May to lay their eggs.