多棘海盘车对魁蚶摄食量、选择性及昼夜摄食差异的初步研究

A Preliminary Study on Food Consumption,Preference and Day-Night Predatory Differential of Asterias amurensis on Scapharca broughtonii

在水温16～20℃、盐度28.2±2.1、溶解氧（7.5±0.7）mg/L、pH8.0±0.3的条件下,研究了3种规格多棘海盘车（Asterias amurensis）对4种规格魁蚶（Sca pharca broughtonii）的摄食量、摄食选择性和摄食昼夜差异.研究表明：多棘海盘车对不同规格魁蚶摄食数量均随魁蚶底播密度的增加而上升;不同规格多棘海盘车对同一规格魁蚶摄食数量无显著差异（P＞0.05）,但对不同规格魁蚶摄食数量存在一定差异,对最小壳长组魁蚶的摄食数量最大;多棘海盘车对不同规格魁蚶软体部摄食量与魁蚶规格呈显著正相关;多棘海盘车对不同规格魁蚶摄食数量均存在一定的昼夜差异且夜间的摄食数量大于昼间,魁蚶规格越大,多棘海盘车的最大摄食数量的时间出现越晚.结果表明：魁蚶适宜底播密度在30 ind/m2左右,底播规格越大越能有效防御敌害.根据多棘海盘车对贝类捕食特点,可采用浅水低值贝类作为诱捕生物对多棘海盘车进行清除.

In order to study the food consumption,preference and day-night predatory differential of Asterias amurensis on Scapharca broughtonii,the experiments were carried out at temperatures ranging from 16 to 20 ℃,salinity 28.2±2.1,dissolved oxygen （7.5±0.7） mg/L and pH 8.0±0.3.The results provided basic data for promoting steady and healthy development of the multiplication and cultivation of S.broughtonii.The results of food consumption suggested that the food intake of starfish increased with the density of S.broughtonii at all conditions.The food consumption of starfish in different sizes on S.broughtonii in the same size had no significant difference（P＞0.05）,but significantly different among S.broughtonii in different sizes.The starfish had the highest feeding rate on the smallest S.broughtonii.Our findings also verified the positive relation between the weight of food intake of starfish in different sizes on the density and size of S.broughtonii.The feeding rhythm of starfish on S.broughtonii in different sizes showed a certain day-night differential,higher in night than on day.The maximum food consumption occurred when the size of S.broughtonii became lager.The results showed that 30 ind/m2 was suitable sea bottom sowing density for S.broughtonii.Our data indicated that the ability to avoid predators and rivals increased as the shell length raise.Based on prey selectivity bivalves that have a lower commercial value may be used to clear away A.amurensis.