哥斯达黎加外海茎柔鱼生物学特性初步研究

Biological characteristics of jumbo flying squid Dosidicus gigasin waters off Costa Rica

根据2009年7-8月在哥斯达黎加外海探捕期间采集的281尾茎柔鱼样本,对其生物学特性进行初步分析。结果表明:茎柔鱼样本胴长范围为205～429 mm,优势胴长为260～360 mm,占81.14%;体重范围为0.17～1.69 kg,优势体重为0.2～1.0 kg,占88.26%;雌雄性比约为3.76∶1,性腺成熟度以Ⅲ和Ⅳ期为主,雄性、雌性性成熟的比例分别为94.92%和66.67%;摄食等级以0～1级为主,占89.32%。体重与胴长关系W=2.35×10-7LM2.5944。相对于加利福尼亚湾、秘鲁和智利外海的茎柔鱼,哥斯达黎加外海茎柔鱼个体较小且体型偏瘦,属于小型或中型群体。

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=2.35×10-7LM2.5944.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.