The vegetation in the 58 hectares surrounding the cave is typical of a seasonal, semi-deciduous premontane forest. The forest contains three dense strata. Among the most common tree species are the araguaney (Tabebuia chrysanta), the naked indian or gumbo limbo tree (Bursera simaruba), the white ramoon (Trophis racemosa), the tuque (Ocotea glandulosa), and the palo de vaca (Poulsenia armata) (MARNR 1992).
Generally, estimates indicate that the many invertebrates found in the caves of Venezuela are from 250 taxa (147 of which have been determined at the species level), while there are approximately 90 vertebrate species. Bat and fish species are the most numerous vertebrates. Approximately 10% of the cave-dwelling fauna are troglobytes, that is, they complete their entire life cycle inside the caves and have evolutionary characteristics specific to these environments, including a loss of pigmentation and atrophy of the eyes (Galán 1995).
In Alfredo Jahn Cave, the frequent flooding of the Cambural Creek, which can completely inundate the cave, has limited the establishment of a troglobyte fauna. As a result, the species of fauna in the cave are principally troglophiles (completing only part of their life cycle in the cave) or trogloxene (occasional visitors to the cave environment). Guano-producing animals are particularly abundant (Bordón 1973).
The Cambural Creek is important for the geologic processes of the cave
There are at least four species of bats documented in the cave, all of which are common in Venezuela: two small insectivorous species (the common mustached bat, Pteronotus parnelli and the funnel-eared bat, Natalus stramineus), a large omnivorous species (the spear-nosed bat, Phylostomus hastatus), and the common vampire bat (Desmodus rotundus rotundus). The latter species is found throughout the country, and there are numerous myths surrounding it, due to the fact that it feeds exclusively on the blood of mammals. One of the most important factors in the expanded distribution of this species in Venezuela has been the introduction of cattle and horses, which the bat attacks during the night (Linares 1998). The most numerous populations of vampire bats in the cave are in the dry sections close to Bocas 2, 3, and 4. Large amounts of guano cover the soil in the areas where these colonies are located.
Six orders of insects have been reported: hymenoptera (ants), coleoptera (beetles), dipterous (flies), neuropteran (lacewings), hemiptera (leaf bugs) and blattaria (cockroaches). There are at least five orders of arachnids, including three species of araneida (Priscula paeta, Wendilgarda miranda, and Achacaranea inopinata). Also, at least two species of shrimp are found in the waters of the Cambural Creek (Bordón 1973).