Ecohydrology and fisheries management

Abstract

Most activities directed toward the conservation of freshwater fish biodiversity have focused on eliminating pollution and habitat degradation. However, according to decision making theory, every successful strategy has to be based on two components: elimination of threats; and amplification of opportunities. The question is, “What are the opportunities in conservation of freshwater fish and their habitats? According to the concept of the new UNESCO IHP‐V programme, ‘Eco‐hydrology’ is the integration of knowledge on the biota dynamics with the whole range of hydro‐logical processes; including the river system, catchment level, and microhabitat. Inclusion of the Eco‐hydrology concept will lead to a better understanding of the hierarchy of regulating factors and evolutionary established resistance/resilience of the freshwater ecosystem to stress. It implementation is especially important for efficient conservation because ecosystem managers have often limited their view to the single causes and simple solutions. To successfully change from a conceptual to an operational stage of the ‘Eco‐hydrology Paradigm’ there needs to be additional research on the dependence of fish life history and physiological performance on hydrological processes. This is chiefly because fish are regulators of processes in whole trophic cascade in aquatic ecosystems.