绥芬河大麻哈鱼增殖放流效果评估

Assessment of enhancement release of Oncorhynchus keta in Suifen River, Northeast China

为评估绥芬河大麻哈鱼增殖放流效果,本研究于2012—2017年在绥芬河东宁段对大麻哈鱼溯河洄游群体进行跟踪监测.共采集样本462尾,其中,标记个体(剪脂鳍)41尾.根据调查数据,计算了大麻哈鱼增殖放流回捕率,评估了增殖放流效果.结果表明:2010—2012年的大麻哈鱼增殖放流回捕率为0.295%,大麻哈鱼增殖放流数量效益为1∶2.87.标记组和非标记组群体年龄组均为1^+~5^+龄,平均年龄分别为3.93和3.63龄.采用Logistic曲线方程计算标记组和非标记组大麻哈鱼的50%初次性成熟叉长(L(50))分别为53.13和49.89 cm.ARSS分析结果显示,大麻哈鱼两组群体的叉长生长差异不显著,但两组间的性成熟比例差异显著.本研究表明大麻哈鱼增殖放流对其资源增殖保护具有重要作用,为今后增殖放流工作提出了建议.

To evaluate the effects of enhancement release of Chum salmon(Oncorhynchus keta)in Suifen River,the homing Chum salmon was monitored in Dongning section of Suifen River from 2012 to 2017.A total of 462 samples were collected,41 samples out of which were tagged individuals which were cut off adipose fin before they were released.The recapture rate and the effects of Chum salmon enhancement release were analyzed and evaluated based on the releasing information.The results showed that the entire recapture rate of Chum salmon from 2010 to 2012 was 0.295%,and the input-output ratio of enhancement release was 1:2.87.Both the tagged and non-tagged groups were composed of 1+to 5+age individuals,with the average age being 3.93 and 3.63 years,respectively.The fork length at 50%individuals reached sexual maturity(L50)was estimated using a logistic moderating function,which was 53.13 cm and 49.89 cm for tagged and non-tagged groups,respectively.Results from ARSS analysis showed that there was no significant difference in fork length growth between tagged and non-tagged groups,but a significant difference in sexual maturity ratio.Our results confirmed the positive effects of enhancement release on recovery of Chum salmon resource and provided suggestions for the enhancement release efforts.