黑龙江拟赤梢鱼资源调查和生物学测定

Resource investigation and biological determination of Pseudaspius leptocephalus in Heilongjiang River

统计了2020年秋季9-10月黑龙江全江段,以及2015年、2019年5-6月抚远乌苏里江通江口至抓吉镇江段拟赤梢鱼(Pseudaspius leptocephalus)的资源、生长和繁殖等生物学调查数据。结果显示:秋季9-10月在黑龙江上游绥滨到漠河江段可捕获到不同大小的鱼体,较大个体达2100 g,从绥滨江段开始捕获有少量的个体,到开库康江段上游捕获数量逐渐增多;春季在黑龙江下游抚远乌苏里江通江口至抓吉镇江段,捕到的个体多数性腺已成熟,体重在477~1254.9 g,体长在34.5~46.5 cm,其中体重在707.6~1098.0 g的数量占到了群体总数的83.68%。对采集到的165尾样本进行生长特征分析,体长(L)与体重(W)的回归方程式为W=0.0061L3.2239(n=165,R2=0.9958),体长、体重的生长方程为Lt=62.456[1-e-0.154(t-0.26)],Wt=4110.2[1-e-0.154(t-0.26)]3.2239,体重生长速度拐点为7.86龄,对应体长、体重为L=43.08 cm,W=1241.53 g。对2019年5-6月份在抚远乌苏里江通江口采捕的49尾鱼进行了繁殖生物学测定,主要为5~8龄性成熟的个体,雌雄性比为♀∶♂=1∶0.88,雌性成熟系数在6.3%~14.3%,绝对繁殖力为15312~41760粒,平均为(26120±7433)粒,雌性6龄组的繁殖贡献率最大,占繁殖群体总繁殖力的52%。

Statistics of Pseudaspius leptocephalus resources, growth and reproduction and other biological survey data in the full reach of the Heilongjiang River Basin from September to October in the autumn of 2020,and the section from the Tongjiangkou of the Wusuli River in Fuyuan to Zhuaji Town from May to June in 2015 and 2019.The results showed that fish of different sizes could be caught in the upstream reach of Heilongjiang River from Suibin reach to Mohe reach, and the larger fish weighed 2100 g.The number of P.leptocephalus caught started from the Suibin reach, and the number of P.leptocephalus caught in the upstream reach of Heilongjiang River were gradually increased.Most of the gonads of the individuals caught in spring are mature, body weight were from 477 to 1254.9 g and body length were from 34.5 to 46.5 cm in the downstream reach of Heilongjiang River from the Tongjiangkou of the Wusuli River in Fuyuan to Zhuaji Town.The number of weights between 707.6 and 1098.0 g accounted for 83.68% of the entire group.Perform regression analysis on the body weight(W) and body length(L) of the collected 165 samples, and the related equation was W=0.006 1L3.223 9(n=165,R2=0.995 8).The growth equation of body length is Lt=62.456[1-e-0.154(t-0.26)]and the growth equation of body weight is Wt=4 110.2[1-e-0.154(t-0.26)]3.223 9.The inflection point of body weight growth rate was 7.86 years, and the corresponding body length growth inflection point was L=43.08 cm, weight growth inflection points W=1 241.53 g.The reproductive biology of 49 fish were caught in the Tongjiangkou of the Wusuli River in Fuyuan county from May to June 2019 was tested, and they are mainly 5-8-year-old sexually mature individuals.The ratio of female to male was =1∶0.88,the female maturity coefficient was ranged from 6.3% to 14.3%,and the absolute fecundity was ranged from 15 312 to 41 760(the average was 26 120±7 433 grains),the female 6-year-old group has the largest reproductive contribution rate, accounting as 52% of the total fecundity of the reproductive population.