东海细点圆趾蟹的生物学特性

根据1998—2000年在东海虾蟹资源调查和渔业生产监测调查中周年采集的1576只细点圆趾蟹样品，开展了基础生物学研究，结果表明，东海细点圆趾蟹的渔获群体甲长分布范围为26～95mm，甲宽为32～120mm，体重为5～410g，雄蟹个体平均大于雌蟹；春季雌蟹生长不明显，而雄蟹则生长迅速，2—6月平均增长率达38．7％；周年雌蟹略多于雄蟹，性比约为1：0．88，繁殖盛期为3—5月，不同个体怀卵量在6．8～75．8万粒之间，最小抱卵个体的甲长为46mm，甲宽为60mm，体重为59g，多数抱卵个体的甲长为50～60mm，甲宽为65～80mm，体重为80～115g。周年摄食强烈，半胃、饱胃率多数时间在50％～60％以上，其中冬春季摄食强度大于夏秋季．

Biological characteristics of Ovalipes punctatus in the East China Sea

Based on the biological study of 1576 samples of Ovalipes punctatus collected every anniversary from 1998 though 2002 in the East China Sea for surveying crustaceans resources and fishery product ion, it was found that the length of carapace ranged from 26 to 95mm and its width from 32 to 120mm. The body weight of them was between 5 to 410 g, in which the male crab seemed bigger than the female one in average. The female crab grew rather slow in spring (February to June) , while the male one grew very fast with an average growth rate of 38. 7%. However, the female crab grew slightly more than the male in the whole year w ith a sex ratio being around 1B0. 88. Moreover, The female crab reproduced vigorously in March to May and the amount of brood for various O. punctatus was between 68000 to 758000. The body weight of the smallest brood crab was 59 g with its carapace length and width being 46 and 60mm, respectively. Most of brood crab had the body weight of 80 to 115 g with the carapace length of 50 to 60 mm and the width 65 to 80 mm. The rate of half or full stomach of crab reached over 50% to 60% .The feeding activity of O. punctatus became stronger in summer and autumn than in spring and winter. On the basis of the quantity distribution and resources situation of O. punctatus in the East China Sea, it is suggested to organize the f ishery to exploit and utilize the resources properly.