Latin american journal of aquatic research
On-line version ISSN 0718-560X
QUEIROLO, Dante et al. Effect of the use of square mesh escape panels on the reduction of young fish in the common hake (Merluccius gayi gayi) trawl fishery. Lat. Am. J. Aquat. Res. [online]. 2008, vol.36, n.1, pp. 25-35. ISSN 0718-560X.
The evaluation of square mesh escape panels in bottom trawl nets used in the common hake fishery was carried out employing two complementary methodologies: top cover and alternated hauls. The top cover hauls were used to quantify the fraction of the catch that escapes through the panels and to determine the size structure and mean weight of the catch, estimating the retention sizes and selection ranges. The fractions under 30 and 36 cm of total length present in the codend and in the top cover were determined as proxies for the selective effect produced by the escape panels. The alternated hauls were used to verify the decrease in the catch rate, both in number and in weight, increasing the mean weight of the retained catch and decreasing the proportion under the reference length, for which we concluded that an escape effect does occur on the young fraction of the stock.
Keywords : escape panels; square mesh; bottom trawl nets; Merluccius gayi gayi; selectivity; juvenile fish; Chile.