Guanacaste Costa Rica
About 8 km north of Playa Nosara you'll find Playa Ostional. During the rainy season it is better to reach it from Junquillal but a 4x4 is needed. This small coastal beach town hosts the national wildlife refuge Ostional a narrow strip about 8 km long but only a few hundred meters wide. the protected land area is 352 hectares; 587 hectares of adjoining sea are also protected.
The main attraction and reason for the creation of the refuge is the annual nesting of the olive ridley sea turtle on Playa Ostional. This beach and Playa Nancite in the Santa Rosa National Park are the most important nesting grounds for the olive ridley in Costa Rica. The nesting season lasts from July to November, August and October are peak month.
The turtles tend to arrive in large groups of hundreds or even thousands - these mass arrivals, or arribadas, occur every three of four weeks and last for about a week, usually on the dark nights preceding a new moon. Trained villagers will guide you to the best places.
Coastal residents used to harvest both eggs and turtles indiscriminately, and this made the creation of a protected area essential for the turtles' continued well-being. An imaginative conservation plan has allowed the inhabitants of Ostional to continue to harvest the eggs from early layings. Most turtles return to the beach several times to lay new clutches and earlier eggs may be trampled or damaged by later layings. thus it seems reasonable that locals harvest the first batches and sell them - they are popular snacks in bars throughout the country.
The leatherback and Pacific green turtle also nest here in smaller numbers. Apart from the turtles, there are iguanas, crabs, howler monkeys, coatis, and many birds. Some of the best birding is at the southeast end of the refuge, near the mouth of the Río Nosara, where there is a small mangrove swamp.
The rocky Punta India at the northwest end of the refuge has many tide pools that abound with marine creatures such as sea anemones, sea urchins, starfish, shellfish, and fish-fish. Along the beach are thousands of almost transparent ghost crabs, bright red Sally Lightfoot crabs, and a variety of lizards. The vegetation behind the beach is sparse and consists mainly of deciduous trees such as frangipani and stands of cacti.
The rainy season lasts from may to December, and the annual rainfall is about 2,000 mm. The best time to see the turtles is the rainy season, so be prepared. The average daytime temperature is 28°C. There's a Universidad de Costa Rica research station, and the villagers of Ostional are helpful with information and will guide you to the best areas.
Ostional has a small pulpería where you can get basic supplies. We stayed at the Cabinas Ostional, which has six rooms with showers and a nice back-yard situated in front of the only restaurant in town. Beware of very stron waves and rip-tides. The beach is not recommended for swimming. We saw some surfers sitting frustrated at the beach saying the the waves are too strong today.