ABSTRACT
Many cave biota have very restricted ranges, and limited opportunities for dispersal. Consequently they are strongly affected by even moderate environmental variability or pollution. The main threats come from a destruction of the habitats by quarrying; increased visitor numbers and vandalism; pollution by heavy metals, herbicides, or pesticides; excess nutrient input; or invasion by an epigean species. The majority of subterranean fauna is not considered in existing national or international protection laws. Only five world conventions are applicable to cave biota and habitats: the Ramsar Convention (1971) in which 12 karst and subterranean hydrological systems are included in 1150 designated wetland areas (see Ramsar Sites); the UNESCO World Heritage List (1972) which includes 13 caves (just 1.8% of the known world caves; see World Heritage Sites); the Washington Convention on International Trade in Endangered Species of Wild Fauna and Flora (1973) where some subterranean species are listed (bats, guácharo or Steatornis caripensis, Proteus anguinus); the Rio Convention (1992) for the protection of biodiversity-although this does not include a detailed list of threatened species; and the International Union for Conservation of Nature and Natural Resources (IUCN) which published a “Red List” of 95 threatened cave biota (Baillie & Groombridge, 1996). There is no specific conservation list for cave flora. Despite these conventions, protection of species from subterranean habitats remains extremely difficult and requires measures to reduce or mitigate the negative impacts of human activities. The main conservation procedures for cave biota are: limitation of visitors in sensitive caves; closure of the most valuable caves; reduction of vandalism; ending pollution from external sources and removal of internal pollution left by cave explorers; rehabilitation of degraded karst ecosystems; and public education and information.
