Long-term and monthly changes in abundance,size composition and spatial distribution of the mantis shrimp Oratosquilla oratoriainthe BohaiSea

With the decline in fish resources worldwide,the ecological dominance and economic importance of crustaceans have obviously increased.Among crustacean species,mantis shrimps are increasingly dominant in many coastal waters of the world.In China,Oratosquilla oratoria is the most widely distributed and productive species of mantis shrimp,and its relative resource density is the highest in the Bohai Sea.In this study,we analysed the long-term and monthly population characteristics of O.oratoria in the Bohai Sea,including its relative resource density,body size and spatial distribution.The results showed that the relative resource density of O.oratoria in the Bohai Sea increased from 3.59 kg/h in 1982 to 14.48 kg/h in 2018,and the percentage of this species that serves as a fishery resource increased from 4.22%in 1982 to 35.27%in 2018,based on the mean relative resource density in May and August.The relative resource density of O.oratoria in the fishing moratorium season from May to August was significantly higher than that in the other months of fishing season,and the relative resource density decreased rapidly after the fishing moratorium ended.The relative resource density of O.oratoria was the highest in summer(August),followed by in autumn(October)and spring(May),and it was the lowest in winter(January).The relative resource density of O.oratoria in the western Bohai Sea was higher than that in the eastern Bohai Sea.The mean body weight of O.oratoria in the Bohai Sea decreased from 21.95 g in 1982 to 14.34 g in 2018,based on the mean body weight in May and August.The body size of O.oratoria in the fishing moratorium season was significantly higher than that in the fishing season,and the body size decreased rapidly after the fishing moratorium ended.Overall,in the context of declining resources of most fishery species,the relative resource density of O.oratoria increased due to its hardiness and adaptability,and its body size decreased under intensive fishing over the past 30 years.The fishing moratorium system had a great influence on the population dynamics of O.oratoria in terms of the relative resource density and body size in the Bohai Sea.

黑斑口虾蛄幼体不同发育阶段的温度、盐度耐受性研究

试验结果表明,黑斑口虾蛄第二相幼体适宜的盐度和温度范围分别为16.98～23.56和20～28℃;第三相幼体适盐与适温范围分别为16.98～26.18和20～28℃;仔虾蛄适盐与适温范围分别为11.73～28.80和18～30℃.环境因子变化对各期幼体成活率有较大影响.当黑斑口虾蛄从第二相幼体发育到仔虾蛄,其对温度、盐度的耐受力增加.

盐度对口虾蛄仔虾摄食、存活和掘穴的影响

为研究口虾蛄（Oratosquilla oratoria）仔虾在人工养殖条件下的盐度适应性,作者分别实验分析了盐度突变和渐变对其累积存活率、摄食率和掘穴行为的影响。实验结果表明,仔虾盐度耐受能力较强,突变组的仔虾存活盐度为15～45,渐变组的仔虾存活盐度为5～54;仔虾的适宜盐度为21～33,24 h存活率在80%以上;盐度对口虾蛄的摄食影响较大,突变盐度为21～33时,仔虾摄食较为活跃,低于18或高于42基本不摄食;盐度渐变组摄食活跃范围为19～38,低于9或高于50基本不摄食;盐度突变对口虾蛄仔虾掘穴的影响显著,盐度突变至21和33时,掘穴时间极显著延长。本实验结果可以为口虾蛄的人工养殖和增殖放流提供参考和依据。

用同工酶和RAPD技术分析黑斑口虾蛄的遗传多样性

采用同工酶技术和RAPD技术对宁波黑斑口虾蛄的遗传多样性进行了分析,采用聚丙烯酰胺凝胶电泳方法(PAGE)对LDH、MDH、MEP、EST、ADH、GDH、GLDH、AMY、POD、SDH等10种同工酶进行了群体生化遗传分析,共检测了29个基因座,其中11个基因座表现为多态,其多态位点比例为37.93%,平均杂合度为0.1470;采用RAPD技术对其遗传多样性进行检测,用24个随机引物共检测出129个位点,其中多态位点为102个,占79.06%,个体间遗传相似系数为0.3106,遗传变异度为0.6894,表明黑斑口虾蛄的遗传多样性状况良好。

东海海域口虾蛄种群遗传多样性

为准确掌握中国沿海口虾蛄（Oratosquilla oratoria）种群遗传结构、合理开发利用其资源,采用线粒体DNA（mt DNA）细胞色素氧化酶Ⅰ（COⅠ）序列分析方法检测东海海域（庙子湖岛、南韭山、大陈岛、南麂岛）口虾蛄种群遗传多样性,并与黄渤海群体和南海群体进行比较分析（基因序列来源于Gen Bank）。经PCR扩增与测序获得100条658 bp的东海海域口虾蛄COⅠ基因序列,基于这些序列分析得到的变异位点数、单倍型数、单倍型多样性指数与核苷酸多样性指数分别为60、60、0.963±0.011和0.005 94±0.000 44,分析认为东海海域口虾蛄具有较高的单倍型多样性和较高的核苷酸多样性。单倍型分子系统树、分子方差分析及两两群体间的遗传分化系数（Fst）分析结果表明,东海海域口虾蛄遗传变异主要来自于群体内（Fst=﹣0.007 78,P〉0.05）,各地理群体间遗传分化不显著,Fst值范围为﹣0.016 53-﹣0.009 08（P〉0.05）,它们可能进行了一定程度的基因交流;通过与黄渤海群体及南海群体基因序列比较分析,口虾蛄东海群体、黄渤海群体与南海群体遗传变异主要来自于群体间（Fst=0.849 71,P〈0.01）,且单倍型分子系统树存在2个显著分化的单倍型类群。东海群体与黄渤海群体间存在显著的遗传分化（Fst=0.884 58,P〈0.01）,而与南海群体间不存在显著的遗传分化（Fst=0.020 44,P〉0.05）,这种遗传结构模式可能与历史上的气候变化及所处海域海洋环境条件相关。建议今后对中国沿海口虾蛄资源进行开发利用时,将黄渤海群体看作一个管理单元,东海群体与南海群体看作一个管理单元。

口虾蛄人工育苗生产技术

根据自己对口虾蛄育苗成功经验，结合国内外学者的研究成果，综述了口虾蛄的交尾、产卵、孵化等繁殖生物学特性，报道了亲虾蛄的选择培育、幼体发育时序、特征和培育技术。