Abstract

Landings of the small-scale longline skate fishery have increased rapidly off southern Chile during the last ten years. At present, the fundamental characteristics for describing the population dynamics (e.g., species composition, catch rates, size structures) are not known. The present study explored these characteristics using biological-fishery information coming from an experimental sampling program carried out between February 2003 and August 2004. A total of 403 fishing hauls were analyzed, and information regarding the fishing operation (date, depth, soak time, number of hooks, total catch, fishing zone) and biological attributes (species identification, number of species, weight, sex, total length) were registered. The catch composition was constructed by fishing zone over 16 species, which corresponded to 98% of the total catch. The catches were dominated by the yellownose skate (Dipturus chilensis) and pink cusk-eel (Genypterus blacodes); together these accounted for 87.8% of the total catch, with the remaining elasmobranch by-catch being less than 9%. The size structures and catch rates were obtained for the pink cusk-eel and both rajiform species (yellownose skate; roughskin skate, Dipturus trachyderma) reported in the catch. The size structures of these three species were significantly different (p < 0.05) by latitude and sex. Monthly variations were also observed in the catch rates.