Fish Fauna of Lake Chapala

Abstract

Lake Chapala is one of the most important reservoirs, which reflects the origin, evolution, and biogeography of freshwater fish fauna in central Mexico. It is the area where more diversity of the endemic subfamily of Goodeinae (“pintillas” and “tiros”), with nine species, is found. This zone outstands for the evolution and sympatric specialization of “charales” and “pescados blancos”, (Atherinidae) which include eight species. It is also the habitat of endemic “bagres” (Ictaluridae), different native carps (Cyprinidae), and historically, it served as the habitat of lampreys (Petromyzontidae). The ichthyofauna of the lake is also very important, at least seventeen of the species provide on-the-spot work of artisan fishery for 1,699 fishermen belonging to 86 fisheries’ co-operatives, and is the local and regional food source. Unfortunately, Lake Chapala presents a high level of environmental degradation, due to a profound modification of the ecosystem. As a result of this fact we can confirm the actual presence of 27 out of 39 registered species, including both native and exotic. Likewise, before 1990 there were high-volume captures (13,710.78 tons per year), however the present production has decreased by a factor of ten. The aforementioned problem cannot be attributed to a single cause, but to a synergetic effect that involves different factors combined with the lack of regulation and pursuit of plans for sustainable development. A contemplated conservation initiative for the restoration of the lake is not the best way to solve the problem. Recommendations are formulated regarding future studies and activities on the situation of the ichthyofauna in the lake.