CINP, unlike other islands of the American Pacific Ocean, is covered by evergreen forest because it is located in the Intertropical Convergence Zone. This ecosystem is distributed throughout the terrestrial part of the island (ONCA and ACMIC, 2007), covering a total area of 2,330 hectares.
As in other oceanic islands, its vegetation is relatively poor in terms of number of species when compared to continental zones, but it has high levels of endemism (Montoya, 1990).
The majority of the native flora (70%) has its origin in Central and/or South America; the rest (30%) is pantropical. Approximately 47.1% of the diaspora of native plants arrived dispersed by the wind; 11.5% arrived by water; 26.7% came in the digestive tract of birds; and 14.7% arrived in the body of birds (Trusty et al., 2006).
By 2006, 366 species of vascular plants had been identified, of which 263 (72%) are native, and 103 (28%) are introduced (71 as of 2004 according to Trusty (2006), plus 32 new species between September 2005 and November 2007, identified by the same author). There are 37 species of endemic plants.
According to Trusty et al. (2006), in the insular part of Cocos Island, the following types of vegetation can be identified:
- Tropical rainforest
- Cloud tropical forest
- Cliff coastal communities
- Riparian vegetation
- Vegetation of the islets
- Bay communities