River conservation in Latin America and the
C.M. Pringle, F.N. Scatena, P. Paaby-Hansen and M. Núñez-Ferrera
|El agua es la luz con raíz en la tierra.||Water is the light with roots on earth|
|Beberla es echarse a caminar como un río.||To drink it is to journey like a river Raul Banuelos, 1994|
The developing nature of Latin America combined with the vastness of its aquatic resources, highly diverse aquatic fauna and flora, rapidly increasing human population, and associated environmental problems, make it a high priority for international riverine conservation efforts. Brazil, Colombia, Ecuador and Peru have been identified by international conservationists as among the 12 ‘megadiversity’ countries which together harbour 70% of the world’s biodiversity (Mittermeier, 1989), thus requiring special attention (McNeely et al., 1990). Specific areas in Latin America that have been classified as ‘hot spots’ of biodiversity and endemism include the Colombian Chocó of western Ecuador, the uplands of western Amazonia, the Atlantic forest region of eastern Brazil, and central Chile (Myers, 1988).
These international conservation priorities were based on high levels of biodiversity and endemism in terrestrial ecosystems. As in many other developing countries (e.g. Benstead et al., this volume) freshwater riverine systems have received comparatively little attention. Comparison of recent regional conservation assessments of freshwater (Olson et al., 1998) and terrestrial (Dinerstein et al., 1995) biodiversity in Latin America and the Caribbean indicate that freshwater biodiversity is more seriously threatened in terms of the geographic extent and severity of threats.
The rich aquatic biodiversity of rivers and streams in Latin America (World Conservation Monitoring Centre, 1992) promises to become an increasingly important criterion for guiding conservation investments. As the largest tropical watershed (5 711000 km2) in the world, the Amazon has well over 2000 fish species, of which 90% are endemic. New species are being discovered every year: a recent study of deep-water habitats of the Amazon revealed more than 240 new fish species (Yoon, 1997).
Over the last few decades, pollution of riverine systems has emerged as a major problem throughout the region (United Nations Economic Commission for Latin America and the Caribbean – UN ECLAC, 1990a, b, c). Among the most important factors contributing to this rapid increase in pollution is the corresponding rapid increase in population growth without the development of waste treatment facilities, land-use planning and pollution control. Latin America contains an estimated 450 million people and the population is growing at an annual rate of 2.1%. It is expected to approach almost 800 million by the year 2020 (World Resources Institute, 1990). In addition, the combined external debt of Latin American countries totalled US$387 billion in 1987, which represents between 10 and 93% of the gross national product of individual nations (World Resources Institute, 1990). Such socio-economic
Global Perspectives on River Conservation: Science. Policy and Practice. Edited by P.J. Boon, B.R. Davies and G.E. Petts. © 2000 John Wiley & Sons Ltd.