许氏平鲉增殖放流苗种网箱中培技术研究

Study on the intermediate rearing technology for proliferation and releasing of Sebastes schlegelii in offshore cages

为研究许氏平鲉(Sebastes schlegelii)大规格苗种网箱中间培育技术,提高其增殖放流的成活率和回捕率,以拟放流的许氏平鲉大规格苗种(体长>5 cm)为对象,分别在沉淀池和天然海域开展了为期28 d的苗种网箱中间培育试验。试验结果显示,在沉淀池培育的许氏平鲉苗种平均全长增长率为30.48%,平均体质量增长率为209.36%,平均存活率为94.28%;在天然海域培育的苗种平均全长增长率为11.47%,平均体质量增长率为102.28%,平均存活率为83.55%。对中间培育苗种的全长和体质量进行拟合,结果显示,在沉淀池培育条件下生长因子b的分布范围为0.879 0~1.353 8,表现为负异速生长。结果表明,许氏平鲉增殖放流苗种的网箱中间培育技术可行,且沉淀池培育的效果优于天然海域。

As one of the important economic species,Sebastes schlegelii is employed for the reproduction and releasing in Yantai,China.The intermediate cultivation of S.schlegelii were conducted in two ways,including cages culture in sedimentation tank or natural sea.The results showed that the average full length of S.schlegelii in cages of sedimentation tank increased by 30.48%,and the average body weight increased from 1.83 g to 5.58 g with a growth rate of 209.36%.The average full length of S.schlegelii cultured in cages of natural sea increased by 11.47%,and the average body weight increased from 1.83 g to 3.70 g with a growth rate of 102.28%.The survival rates were 94.28%and 83.55%in cages of sedimentation tank and natural sea,respectively.By function fitting of the full length-weight relationships of S.schlegel in the cages of sedimentation tank,it was found that the distribution of allometric factor b ranged from 0.8790 to 1.3538 with an average of 1.0540,showing a negative allometric growth.These results suggested that the intermediate cultivation of S.schlegelii in cages of sedimentation tank was better than that of natural sea based on higher full length,body weight and survival rate.