There are 6 different ecological zones in this preserve. It is called a cloud forest rather than a rain forest because of it's altitude: The clouds pass through the forest tree tops (canopy). The canopy is extremely rich with birds like the Three-wattled Bellbird and the Resplendent Quetzal. This particular bird is usually seen in March-April during their nesting season. The Preserve extends down both the Caribbean and Pacific slopes. The consequential combination of climatic and geographic factors creates temperature and humidity gradients which transform considerably over fairly short distances. Also the significant rainfall and broken terrain combine to make breathtaking crystal clear water cascades.

The altitude varies from about 600 (ft?) meters in the lower areas of the Peñas Blancas River, to 1842 (ft?) meters at the top of Cerro Tres Amigos. In 1972 under the threat of homesteading in the surrounding rain forest, visiting scientists George Powell and his wife joined forces with long-time resident Wilford Guindon to promote the establishment of a nature preserve. The Tropical Science Center was receptive to these efforts and accepted institutional responsibility for ownership and management of the protected areas. An initial land purchase of 328 hectares formed the core of the Monteverde Cloud Forest Preserve, Costa Rica. In 1975 the 554-hectare community watershed reserve, founded in the mid-60s by members of the Quaker community and named Bosque Eterno S.A., was annexed under an administrative contract to the Preserve.After the Preserve's creation, the Tropical Science Center continued to secure the financial and human resources necessary to expand, consolidate, and properly protect and manage the Rainforest Preserve's current 10,500 hectares.