Distribución y abundancia de la gamba Haliporoides diomedeae (Crustacea: Decapoda: Penaeidae) frente a la

Abstract

A survey over the continental slope off the central coast of Chile (32°10'S a 34°42'S), with a bottom trawl net, was conducted to gather fishing-biological antecedents and assess the red royal shrimp resource (Haliporoides diomedeae), between August 8th and September 16th, 2002. The sampling design was set in two steps, with transects perpendicular to the coast, separated by 10 nm. Assessment hauls between them were performed to improve the estimates precision. The total catch of the species reached 11 ton. Samples were taken on each haul. Measurements were taken on 50.713 specimens, recording carapace lengths (Lc) between 12 and 72 mm, with a mean of 30 mm and mode at 28 mm. Length at physical maturity (Lc), was established in 32,5 mm for males and 37,5 mm for females. During the study a total of 265 fishing hauls were taken between 295 and 682 m, obtaining 179 positive trawls with red royal shrimps. The highest yields were obtained over 500 m depth. The resource was found to be distributed in two abundance aggregates of 620,5 and 539,2 km2 each, separated by the San Antonio Canyon. The vulnerable biomass determined in the study area was between 702 and 745 tons, of which 237,7 tons correspond to specimens with length over first physical maturity According to these results, the red royal shrimp is positioned as a complementary resource among other crustaceans traditionally exploited in shallower waters.