多棘海盘车对四种贝类摄食率和选择性的初步研究

Feeding rate and food preference of Asterias amurensis on four species of bivalves

在水温为22～24℃,盐度29.6,溶解氧6.9 mg/L,pH 8.01的条件下,研究了多棘海盘车(Asterias amurensis)对4种贝类栉孔扇贝(Chlamys farreri)、贻贝(Mytilus edulis)、东方缝栖蛤(Hiatella orientalis)、菲律宾蛤仔(Ruditapes philippinarum)的摄食与食物选择性,以期了解多棘海盘车摄食生理生态学特性。结果表明:当只有一种贝类作为饵料时,多棘海盘车对不同贝类的摄食率差异极显著(P<0.01)。其中,对东方缝栖蛤的摄食率最大,为0.005 7～0.008 0 g干重/(h.只)(壳长为7～20 mm),其次是贻贝为0.003 5～0.004 9 g干重/(h.只)(壳长为10～21 mm),对栉孔扇贝的摄食率最小,为0.001 4～0.002 8 g干重/(h.只)(壳长为14～31 mm)。同时,多棘海盘车的摄食率还表现出一定的昼夜差异,夜间的摄食率大于白天,但差异并不显著(P>0.05)。当4种贝类同时作为饵料存在时,多棘海盘车对东方缝栖蛤的摄食率最大,为0.003 0 g干重/(h.只),其次是贻贝为0.001 7 g干重/(h.只),以摄食率评价摄食选择,多棘海盘车对于该4种贝类具有明显的选择性(P<0.05),其摄食选择性的顺序为:东方缝栖蛤,贻贝,菲律宾蛤仔,栉孔扇贝。

In order to study the feeding-physiological ecology of starfish（Asterias amurensis）,the feeding rate and food preference to four species of bivalves were determined at temperature 22-24 ℃,salinity 29.6,dissolved oxygen 6.9 mg/L and pH 8.01.The results of feeding rate suggested a significant difference（P0.01） when culture of the starfish with each bivalve,respectively.The starfish had the highest feeding rate on Hiatella orientalis at 0.005 7-0.008 0 gdw/（h·ind）（the shell length was 7-20 mm）,followed by Mytilus edulis（0.003 5-0.004 9 gdw /（h·ind）,the shell length was 10-21 mm） and the lowest feeding rate on Chlamys farreri（0.001 4-0.002 8 gdw /（h·ind）,the shell length was 14-31 mm）.At the same time,the feeding rate of starfish on the bivalves also showed a certain difference of day and night,exhibiting the higher feeding rate during the night than day,but the difference was not significant（P 0.05）.When cultured with four species of bivalves together,the starfish also showed the highest feeding rate on H.orientalis 0.003 0 gdw/（h·ind）,followed by M.edulis 0.001 7 gdw /（h·ind） and less preference feeding on the C.farreri and R.philippinarum.The starfish had obvious selectivity（P0.05） on four species of bivalves by the feeding rate,and the sequence ranked after the feeding selectivity was H.orientalis,M.edulis,R.philippinarum,C.farreri.