Freshwater Protected Areas: Strategies for Conservation

Abstract

Freshwater species and habitats are among the most threatened in the world. One way in which this growing conservation concern can be addressed is the creation of freshwater protected areas. Here, we present three strategies for freshwater protected-area design and management: whole-catchment management, natural-flow maintenance, and exclusion of non-native species. These strategies are based on the three primary threats to fresh waters: land-use disturbances, altered hydrologies, and introduction of non-native species. Each strategy draws from research in limnology and river and wetland ecology. Ideally, freshwater protected areas should be located in intact catchments, should have natural hydrological regimes, and should contain no nonnative species. Because optimal conservation conditions are often difficult to attain, we also suggest alternative management strategies, including multiple-use modules, use of the river continuum concept, vegetated buffer strips, partial water discharges, and eradication of exotic species. Under some circumstances it may be possible to focus freshwater conservation efforts on two key zones: adjacent terrestrial areas and headwaters. Áreas Protegidas de Agua Dulce: Estrategias para la ConservaciónResumen: Las especies y hábitats de agua dulce se encuentran entre los más amenazados del mundo. Una forma en la que esta creciente preocupación por la conservación puede ser abordada es la creación de áreas protegidas de agua dulce. Aquí presentamos el diseño de tres áreas protegidas de agua dulce y las estrategias de manejo: manejo global de la cuenca de captación, mantenimiento del flujo natural y exclusión de las especies no nativas. Estas estrategias están basadas en las tres amenazas principales que tienen las aguas dulces: perturbaciones por uso del suelo, hidrologías alteradas e introducciones de especies no nativas. Cada estrategia está planteada como resultado de la investigación en limnología y ecología de ríos y pantanos. Idealmente, las aguas protegidas de agua dulce deberán ser ubicadas en cuencas de captación intactos, que tengan regímenes hidrológicos naturales y que no contengan especies no nativas. Puesto que las condiciones óptimas de conservación son frecuentemente difíciles de alcanzar, también sugerimos estrategias alternativas de manejo que incluyen módulos de uso múltiple, uso del concepto de río continuo, bandas de amortiguamiento con vegetación, descargas parciales de agua y erradicación de especies exóticas. Bajo ciertas circunstancias, puede ser posible enfocar los esfuerzos de conservación de aguas dulces en dos zonas clave: áreas adyacentes terrestres y nacientes.

Fish fauna in Iberian Mediterranean river basins: biodiversity, introduced species and damming impacts

“…In the context of the contemporary massive loss of biodiversity, freshwater ecosystems have been frequently cited among the most altered and threatened by human activities (Mason, 1991;Dynesius and Nilsson, 1994;Saunders et al, 2002). Though first approaches to decline and extinction phenomena were mostly centred on terrestrial organisms, conservation of freshwater fauna has received increasing attention in recent times (Richter et al, 1997;Harding et al, 1998;Ricciardi and Rasmussen, 1999).…”

“…Nevertheless, though smaller basins feature fewer and less distinct species, small undammed basins are so far the only ones that maintain pristine fish communities. It is therefore also important to preserve these water courses (Saunders et al, 2002), since flow alterations would increase the probability of their invasion by introduced species.…”

An inventory of mammals, birds and reptiles along a section of the river and banks of upper Ganges, India

“…Freshwater biodiversity constitutes a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms (Dudgeon et al 2006). However, there is an increasing concern worldwide on the loss of aquatic ecosystems and their associated biodiversity (Georges & Cottingham 2002;Saunders et al 2002;Cullen 2003), particularly for riverine landscapes (Dunn 2004). Rivers and associated freshwater habitats are among the most threatened ecosystems of the world (Revenga et al 2005;WWF 2006) due to a wide range of intensive human use and developmental activities.…”

Structure of endemic fish assemblages in the upper Yangtze River Basin

“…The widespread changes in biodiversity alter ecosystem processes and change the resilience of ecosystems (Chapin et al, 2000). Therefore, the dramatic loss of biodiversity (Chapin et al, 2000;Abell, 2002;Saunders et al, 2002) implies conservation of natural resources and biodiversity is a focus for managers. For this purpose, minimizing the loss of biodiversity may act as a conservative strategy for maintaining the global values of ecosystem services.…”