Investigation into the declining trend in Chokka squid loligo vulgaris reynaudii catches made by South African trawlers

afrique du sud agotamiento de recursos bycatch calamar calmar capture accessoire chalutage datos sobre pesca descartes distribution spatiale fishery data geographical distribution loligo vulgaris pesca a la rastra rendement rendimiento resource depletion spatial distribution squids statistical data tendance tendencias trawling trends yields