Ecología trófica de la merluza común (Merluccius hubbsi) del Mar Argentino. Parte 3. Consumo anual de alimento a nivel poblacional y su relación con la explotación de las pesquerías multiespecíficas.

Abstract

The English contents gives a general view on the topics treated in this contribution developed mainly on the basis of a quantitative and ecological analysis of trophic relationships in the Argentinian Continental Shelf, in which common hake and its food species are involved (anchovy, mictophids, small fishes, squids and macrozooplankton crustaceans). The most original part consist in the application of bioenergetic and simulation models for estimating the annual food consumption by individuals and by stocks of common hake during 1970-1987, considering at the same time, the effects of commercial catches on the stockbiomasses in predator-prey relationships. From this point of view three trophic-fishery relationships are evident, namely: "Common hake-Anchovy"; "Common hake-squids" and "Common hake-Common hake". The first one refers to a potential fishery, since the anchovy stocks are not yet intensively exploited; in the second relationship, the stocks of both integrant species makes the object of the main argentinian marine commercial fisheries; and the third corresponds to cannibalism. Consequently, the importance of the "tropic catch", that is to say, the food biomass consumed by the common hake stocks (corresponding to a part of the natural mortality M) and the necessity to consider this catch together with the commercial catch to attain a complete management strategy for the multispecies fisheries in the region of the Argentinian Continental Shelf.