2004年乌苏里江大麻哈鱼生殖群体结构研究

Investigation of Chum Salmon(Onconhyn chas keta) Breeding Stock Constitution in Wushuli River

2004年9月10日～10月20日,对乌苏里江大麻哈鱼(Onconhynchas keta)生殖群体随机取样81尾,对其体长、体重组成、年龄与生长、生殖,成熟系数及肥满度等生殖群体结构特征进行测定.结果表明,2004年度的溯河生殖群体主要由2+～4+龄个体组成,其中3+龄占数量优势(72.0%),体叉长平均为62.6±5.24cm,其中60～65cm体叉长占数量优势(38.3%);体重平均为2.95±1.92kg,其中以2～3kg体重占数量优势(55.6%);绝对生殖力平均为2868.7±859粒;相对生殖力平均为0.8328±0.25粒/g;性成熟系数♀群为12.04～25.00%,♂群为2.64～4.47%;肥满度♀群平均为1.1149±0.12%,♂群为1.0843±0.10%.2004年乌苏里江大麻哈鱼种群数量为2.5×104尾,生殖群体数量处于濒危状态,亟待加强保护.

From September 10, 2004 to October 20, 2004, we investigated the breeding stock constitution of Chum Salmon in Wushuli River, including measurement of body length, body weight, plumpness, age, growth, fecundity and mature coefficient. the result of investigation shown that 2004＇ s breeding stock was mainly constituted by 2 - 4year single and the dominating stock was 3year parents （about 72%）. In the breeding stock, average body length was 62.6 ± 5.24em and average body weight was 2.95 ± 1.92kg. In dominating breeding stock, average body length was 60- 65cm （38.3%） and body weight was 2 - 3kg （55.6%）. For breeding females, average absolute fecundity was 2868.7 ± 859 eggs and average relative fecundity was 0.8328 ± 0.25eggs/g. In all breeding parents, female＇ s mature coefficient was 12.04 - 25.00% and male＇ s was 2.64 - 4.47%, female＇ s average plumpness was 1.1149 ± 0.12% and male＇ s was 1.0843 ± 0.10%.