Age, maturation, and population structure of the Humboldt squid Dosidicus gigas off the Pe

Age, maturation, and population structure of the Humboldt squid Dosidicus gigas off the Peruvian

Exclusive Economic Zones

LIU Bilin;CHEN Xinjun;CHEN Yong;TIAN Siquan;LI Jianhua;FANG Zhou;YANG Mingxia

【期刊名称】《中国海洋湖沼学报（英文版）》 【年(卷),期】2013(031)001

【摘要】Age,maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008-2010.Estimated ages ranged from 144 to 633 days,confirming that the squid is a short-lived species with longevity no longer than 2 years.Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round.Back-calculated hatching dates for the samples were from January 22nd,2008 to April 22nd,2010 with a peak between January and March.Two size-based and two hatching date-based populations could be defined from mantle length (ML) at maturity and back-calculated hatching dates,respectively.Females matured at a larger size than males,and there was a significant difference in ML at maturity between the two hatching groups (P＜0.05).The waters adjacent to 11°S off the Peruvian EEZ may be a potential spawning ground.This study shows the complexity of the population structure and large variability in key life history parameters