Ecological traits and fishery of the Upper Limay River, a key system for salmonids in Andean north Patagonia

Abstract

The upper Limay river basin constitutes one of the most relevant fluvial systems in the Andean northern Patagonia. The Limay river is the outlet for the great Nahuel Huapi lake, it receives the waters of several streams, both permanent and temporary regimes and the Traful river. Its waters feed the Alicura reservoir. This entire huge river system has populations of diverse species of fish, both native and exotic. The latter include rainbow, brown and brook trout, with a relatively small population of Atlantic salmon, mainly confined to the river and lake Traful. The Limay River and its tributaries are used by the different species of salmonids as spawning and rearing environments, both by the resident populations in the water courses and by migrant fractions, which reach the river from the lakes of the headwaters. These environments are not homogeneous, observing differential distributions of the species along the main course of the river and in the tributaries, interspecific interactions among salmonids species and amnog them and the native species, and even possible effects of fish escaped from rainbow trout farms located in Alicure. The Limay River is also the limit of the Nahuel Huapi National Park, there is an interesting need for the administration of the ichthyofauna, with the protection and conservation of the native fauna, and the management of a recreational fishery of the first order with a very important economic movement . The work carried out over time by research aimed at understanding trophic relationships, reproductive movements, uses of the environment by different species and different aspects of the sustainable exploitation of a fishery are summarized and analyzed here.