Fish and Fisheries of the Patagonian Steppe

Abstract

The Patagonian steppe is a vast territory with a diverse array of aquatic environments with low fish richness, including several exotic species which are mostly salmonids. Unlike the Andean region, knowledge of the ichthyofauna and fisheries of the Patagonian plateau is comparatively scarce. The characteristics of the ichthyofauna and their assemblages and fisheries vary greatly in the large basins that cross the steppe. Fish assemblages of north Patagonia include elements of the Patagonian, Andean Cuyean, and Pampean ichthyological provinces, where Austral and Brazilic subregion species overlap. Salmonid richness increases from northern to southern latitudes, as do anadromous species. The steppe also presents some endorheic basins inhabited by species of high conservation value and restricted distribution. Threats and impacts that have been identified include land and water use, damming, pollution, climate change, and exotic species introduction. Historical and current management policies have permitted uncontrolled stocking of exotic species due to their high fishing value, thus favoring a reduction in the distribution and abundance of native fishes, including endangered species with an extreme degree of endemism.