Freshwater fishes of the Altiplano

Abstract

Fisheries of the Altiplano, dating from 1500 to 2000 BC, are active in the Andean inter-montane plateau that extends from Ancash, Peru, to Antofagasta, Chile, at altitudes above 3600 m. The ancient and remote nature of these systems has merited the inclusion of many areas as National Parks and RAMSAR sites. Among 58 native fish species, 45 belong to the killifish complex Orestias and the rest to the catfish complex Trichomycterus. The main fishery resources consist of "ispi", Orestias ispi, with 32 175 (64.5%) metric tons and "karachi", Orestias of the group agassii, with 455 metric tons (0.9%). The introduced fishes "silversides", Odontesthes bonariensis, and "trouts", Oncorhynchus mykiss, contribute 16 900 metric tons (33.9%) and 324 metric tons (0.7%) respectively. Hydro-acoustic evaluations show a permanent diminution of the endemic Orestias. Lake species such as O. pentlandii "boga" and O. cuvieri "humanto" were important for their biogeographic relationships and were highly endemic. Native fishes are nowadays threatened by the salmonids, Oncorhynchus mykiss, Salvelinus namaycush, Salvelinus fontinalis and Salmo trutta, introduced since 1939. Later the silverside Odontesthes bonariensis was introduced during 1955-1956