獐子岛深水人工鱼礁区大泷六线鱼生长特性研究

为评估獐子岛深水人工鱼礁区大泷六线鱼Hexagrammos otakii的生长特性及其资源变动情况,利用Von Bertalanffy生长方程分析了该海域大泷六线鱼体长与体质量的关系式、生长方程、各项生长参数和生长特征变化情况,运用FISATⅡ软件评估了鱼礁区大泷六线鱼的可捕资源量,分析了投放人工鱼礁对大泷六线鱼生长特性及资源量的影响,并提出了大泷六线鱼渔业资源可持续发展管理措施及资源合理利用的建议。结果表明:人工鱼礁区大泷六线鱼的平均体长和体质量随年份的增加基本呈上升趋势,优势体长组和优势体质量组随年份的增加均呈递增趋势,优势体长组为161~200 mm,优势体质量组为81~120 g;体质量生长的拐点年龄为3.75 a,种群生物量增长的临界年龄为3.73 a,总瞬时死亡率为0.483/a;根据体长股分析法,计算出鱼礁区(800 hm~2)大泷六线鱼可捕资源量为1571.6 t(约196.4 g/m~2)。研究表明,合理的捕捞限制应为3.73 a,最小不低于3 a,对体长小于281.6 mm、体质量小于273.7 g的大泷六线鱼应予以保护。

Growth performance of fat greenling Hexagrammos otakii in artificial reef areas in Zhangzi Island

The length-weight formula, growth equation, growth parameters, and changes in growth characteristics were studied by Von Bertalanffy growth equation in fat greenling Hexagrammos otakii in the deepwater artificial reef area of Zhangzi Island and fishery stock of fat greenling in that waters was estimated by FISATⅡ to understand growth characteristics and resources variation of fat greenling in the surveyed area. The effects of artificial reef con-struction on fat greenling growth characteristics and resources were discussed, and suggestions on the fishery re-sources management measures were put forward for sustainable development and resource reasonable utilization of the fat greenling fishery. The results showed that mean body length and body weight including dominant body length and body weight were tend to be increased annually, with dominant body length of 161-200 mm and dominant body weight of 81-120 g. The inflexion of body weight growth was observed at age of 3. 75 years, and the critical bio-mass of fat greenling was found at age of 3. 73 years, with the total instantaneous population mortality of 0. 483 a year. The overall population biomass of fat greening stands was estimated to be 1571. 6 ton(about 196. 4 g/m2) in artificial reef areas(800 hm2 ) by the Length based Cohort Analysis supported by FISATⅡ. The findings indicate that rational catchable age of the fat greenling should be over 3. 73 years old, at least over 3 years old and the mini-mum catchable size 281. 6 mm in body length, and 273. 7 g in body weight, the fat greenling less than these sizes being protected.