日本蟳捕食栉孔扇贝机制的初步研究

在现场和室内条件下研究了日本蟳(Charybdis japonica)对栉孔扇贝(Chlamys farreri)的捕食机制。现场实验表明,成年日本蟳可以捕食壳高小于5.0 cm的栉孔扇贝,其捕食强度随着水温的升高而增大,而壳高大于5.9 cm的栉孔扇贝则可以免遭日本蟳的捕食;相对于栉孔扇贝,日本蟳更倾向于捕食贻贝;室内实验表明水温低于10℃时,日本蟳对大规格扇贝的捕食作用不明显。相同温度条件下,室内实验日本蟳的捕食强度要低于现场,但其温度系数(Q10)差别不大。在上述实验基础上,本文提出了提高底播栉孔扇贝成活率的方法,即选择大规格的扇贝在水温较低的秋、冬季进行底播,同时添加一部分贻贝作为牺牲诱饵以减少日本蟳对扇贝的捕食。

Predation of scallop Chlamys farreri by crab Charybdis japonica

Predation of scallop Chlamys farreri by crab Charybdis japonica was examined in situ and in the laboratory at different water temperatures. It was found that the predation rate of small scallop (shell height < 5.0 cm) was increased with increasing water temperature, and the predation was negligible either when the shell height of scallop exceeded 5.9 cm or when the water temperature was blow 10°C. In situ predation rate was higher than that in the laboratory at the same seawater temperature; however, the Q10 values were similar at the two different situations. Our results indicate that the best way to enhance the survival of the bottom cultured C. farreri is to seed large scallops in autumn and winter, when the water temperature is low, and some mussels should also be put in the culture area as a sacrifice to reduce the predation of scallop by crab.