Forecasting the stock size of the autumn cohort of Japanese common squid (Todarodes pacificus) based on the abundance of trawl-caught juveniles
Forecasting the stock size of the autumn cohort of Japanese common squid (Todarodes pacificus) based on the abundance of trawl-caught juveniles
复制标题
根据拖网捕获的幼鱼数量预测日本鱿鱼 (Todarodes pacificus) 秋季群体的种群规模
作者：
H. Kidokoro;T. Shikata;Shinsuke Kitagawa
对日本鱿鱼（Todarodes pacificus）秋季群体幼鱼的分布及其与海洋条件的关系进行了分析，以探讨它们是否可以用于准确预测种群规模。 2001年至2010年4月期间，总共使用5艘研究船在日本南部海进行了研究巡航。在大约0-10 m深度的331个拖网中，捕获了267个幼鱼，每个拖网捕获的数量从0到1087。根据背幔长度（DML）将样本分为秋季和冬季组。海面温度在 10 至 11 °C 范围内的秋季种群数量丰富（40 个/丝束），而在温暖的水域则数量较少。该群体在近海地区更为丰富，而冬季群体在近岸地区更为丰富。秋季群体的平均捕获量被用作每年幼鱼数量的指标。该指数与股票规模显着相关。这些结果表明，在捕捞季节之前，可以根据幼鱼的丰度来预测太平洋砗磲秋季群体的种群规模，但由于观测误差，这种关系高度不确定。
The distribution of juveniles of Japanese common squid (Todarodes pacificus) autumn cohort and its relation to oceanographic conditions were analyzed to see if they can be used to accurately forecast the stock size. Research cruises was conducted using a total of 5 research vessels during 2001-2010 in April in the southern Sea of Japan. Juveniles were caught in 267 of 331 tows of a trawl net at approximately 0-10 m depth, and the numbers caught in each tow ranged from 0 to 1087. Samples were divided into the autumn and winter cohorts based on the dorsal mantle length (DML). The autumn cohort was abundant (40 inds / tow) where the sea surface temperature ranged from 10 to 11 °C and less abundant in warmer water. This cohort was more abundant in offshore areas, while the winter cohort was more abundant near shore. The mean catch of the autumn cohort was used as an index of the annual abundance of juveniles. This index and the stock size were significantly correlated. These results suggest that the stock size of the T. pacificus autumn cohort can be forecasted before the fishing season based on the abundance of juveniles, but this relationship is highly uncertain due to observational errors.