1. The Osa is the most bio-diverse place in the world because 50% of all Costa Rican species are here. The Osa covers only 5% of the land mass of Costa Rica, around 1000 square km compared to the almost 20,000 that Costa Rica covers.
2. The Osa has the last remaining lowland rainforest along the Pacific coast of Central America. This is important as Caribbean rainforests and even Pacific rainforests in South America hold a very different biodiversity.
3. The Osa holds many endemic species due to the joining of two land masses 2 million years ago. Many animals never made it across the Talamanca mountain range so are limited to the Osa. 10% of flora (plants) are found nowhere else in the world and 25% of amphibians are endemic.
4. The Osa is a migratory route and seasonal feeding ground for many species of birds from the United States and Canada.
5. The Osa has a wide variety of habitats/micro climates, supporting some of the worlds most threatened ecosystems including mangrove forests and wetlands. It holds the most significant wetland ecosystem and mangrove forests of Central America.
6. The Osa has the largest population of Scarlet macaws in Central America and one of the only remaining populations in Central America.
7. The Osa boasts more than 700 species of trees (which is more than all the Northern temperate regions combined!!!)
8. The Osa has 234.8 plant species per 1000 square km, Colombia, the 2nd most biodiverse has only 43.8 plant species per 1000 square km.
9. The Osa holds 28.2 species of vertebrates (excluding fish) per 1 000 km2, Ecuador, the 2nd most biodiverse has 9.2 species per 1 000 km2, and the third most biodiverse vertebrate country, Malaysia, has only 4.4 vertebrate species per 1 000 km2.
10. The Osa has 463 species of birds, one of the highest densities in the world.
11. There are 140 species of mammals, including 25 species of dolphins and whales.
12. There are 4 species of sea turtles that nest on the beaches on the Osa.