Biological characteristics of jumbo flying squid Dosidicus gigas in waters off Costa Rica

Abstract:

During the trial fishing in the open waters off Costa Rica in the central east Pacific in July and August 2007, 281 jumbo squid Dosidicus gigas were sampled to examine the biological characteristics. The squid mantle length ML ranged from 205 to 429 mm, and the dominant size between 260 mm and 360 mm which accounted for 81.14% of the total. Body weight was 0.17-1.69 kg, in which 88.26% was 0.2-2.0 kg. The female : male ratio was 3.76∶1. Maturity stages for the squid was mainly at Ⅲ and Ⅳ. 94.92% males and 66.67% females were mature. Feeding stage 0 and 1 attained 89.32%. The MLweight relationship was expressed as W=2.35×10^-7L_M^2.5944. It can be found that the size of jumbo squid off Costa Rica was smaller and thinner than that in the Gulf of California and waters off Chile and Peru, which indicated that jumbo squid off Costa Rica belongs to small or mediumsized group.