Wildlife Species

Banner Lizard 1



The island of Puerto Rico was formed by volcanic activity during the Triassic period. Thrusting out of the Caribbean sea it had no land bridge to any continent. Consequently, the animals of Puerto Rico (and El Yunque National Forest) originally arrived on the island by either swimming, floating or flying, and thus were smaller in size than those found on large continents. The largest mammalian animals in the forest are two species of rats, eleven bats, the house mouse and the mongoose.



El Yunque National Forest provides habitat for 97 bird species of which 45 are migratory.



There are many types of reptiles to be found in El Yunque, some of which you are likely to see on your visit to the forest.  There are various types of lizards, anoles, geckos and snakes.  Click on the links for full descriptions of all species:




Aquatic Species

The rivers and streams of El Yunque provide aquatic habitats for organisms that are important elements of the forest’s biological diversity, including: seven species of fish, nine species of freshwater shrimp, and 1 species of freshwater crab.

Stream invertebrates are important year- round consumers of forest leaf litter and operate as miniature water treatment plants.

All of these species can be commonly found in any of the rivers or streams of the forest, but they are particularly easy to spot in the Mameyes River (Angelito Trail, Puente Roto, La Coca Trail). The Mameyes River is the only river in the Island that runs un-interrupted from its origin to the sea.  Therefore the Mameyes system enjoys the highest natural aquatic diversity and species richness of any Forest watershed. 

Aquatic Invertebrates


Land Invertebrates

Insects and other invertebrates found in leaf litter are important components in decomposition, nutrient cycling, and food webs.  Below is a small listing of some of those you may see in El Yunque.