Estimating the maximum sustainable yield of bonito (Sarda chiliensis, Scombridae) of northern Chile from monthly catch data

Monthly catch data of bonito Sarda chiliensis from northern Chile, from 1976 to 1989, were used to obtain a series of estimates of the Z-G parameter (i.e., total mortality minus the growth coefficient in weight). This series was then used to estimate a maximum sustainable yield of 4,500 t/year through a modified version of the surplus production model of J. Csirke and J. Caddy. The status of the fishery is discussed.

Comparative growth performance of jack mackerels of the genus Trachurus with emphasis on T. symmetricus murphyi in Chile

This contribution presents von Bertalanffy growth parameter estimates for species/stocks of jack mackerels of the genus Trachurus from around the world, and compares them with growth parameters for T. symmetricus murphyi caught off central-Chile (33 super(o)S-39 super(o)S). It is found that Trachurus stocks inhabiting upwelling areas such as the Humboldt and Benguela current systems grow better than their ecological equivalents in temperate waters, such as the North Sea. The von Bertalanffy growth paramters estimated from Chilean horse mackerel are: FL = 65.2 cm (TL = 71.6 cm) and K = 0.138 year super(-1).

Decision analysis applied to the fishery of the sea snail Concholepas concholepas from central northern coast of Chile

Formal decision analysis was applied to the management of loco (Concholepas concholepas, Fam. Muricidae) in Chile, 29-35 degrees S. Four interested groups were considered "Fishers", "Scientists", "Buyers" and the "State", along with three fishing effort levels and four subobjectives. The method was found to encourage the emergence of a consensus (here: halving of effort), and is recommended for use in other fisheries.