Located in the southwest corner of Costa Rica, the Osa Peninsula encompasses lush primary rain forests and a complex system of freshwater and marine resources. Jutting out into the Pacific Ocean, the remote Osa peninsula region also includes the Piedras Blancas National Park and off the southwestern coast, the Isla del Caño Biological Reserve.
With an assisted land acquisition of 86,485 acres in 1975, The Nature Conservancy helped the Costa Rican government create the more than 100,000 acre Corcovado National Park on the western part of the peninsula.
This area hosts a rich array of fauna including: Jaguar, Central American squirrel monkey,
Baird's tapir, Three species of sea turtles (olive ridley, Pacific green, and leatherback). More than 375 bird species are also found on the Osa Peninsula including the country's largest population of the threatened scarlet macaw. Osa is also home to the harpy eagle and the yellow-billed cotinga.
A fourth of Costa Rica's tree species, are found on the Osa Peninsula, including the newly discovered genus, Ruptiliocarpon (Lepidobotryaceae). Also, the Osa Peninsula supports more than 4000-5000 vascular plant species, many of which are endemic.