Reproduction of the Humboldt squid (Dosidicus gigas) off Peru

Abstract:

In this study, we analyzed the reproduction of the Humboldt squid (Dosidicus gigas) based on 2 489 individuals collected off the Peruvian waters during January 2008 to October 2010 by Chinese jigging vessels. The number of females of D. gigas was significantly greater than that of males in the study area and the ratio of female to male was 3.99:1. The occurrence of mature individuals in each month showed that D. gigas spawn all the year round, although only 10.4% females and 21.3% males matured among the total samples. Nidamental length showed significant power correlations with nidamental weight. Nidamental gland and gonad somatic index increased with gonad maturity gradually from gonad maturity Stage Ⅰ to Ⅳ, but slightly decreased at Stage Ⅴ due to mating and spawning (P<0.05). The relative frequency distribution for mantle length classes fitted Logistic model. This showed that mantle length at maturity of D. gigas was 539 mm for females, and 507 mm for males.