人工养殖条件下香螺摄食行为研究

Study on feeding behavior of Neptunea arthritica cumingii under artificial culture conditions

应用实验生态学方法,以长牡蛎、卤虫、鳀鱼及海湾扇贝为饵料,研究了香螺的摄食行为。结果发现,香螺摄食方式为伸出口吻利用齿舌刮取食物,趋向食物时具有方向性;进食时无法锁定食物,且需要暗光环境。实验观察香螺对4种饵料生物均有摄食,但对长牡蛎的摄食指数达到不摄食水平;对鳀鱼的摄食指数最高,达到0.290±0.040,但与卤虫摄食指数相比差异不显著(P>0.05),对两种贝类的摄食指数明显偏低,对4种饵料生物摄食喜好程度总体为鳀鱼>卤虫>海湾扇贝>长牡蛎。香螺属于明显的夜间摄食型节律,白天即使仍存在饵料生物也极少摄食,夜间特定摄食指数达到0.672±0.011,与晨昏摄食指数差异显著(P<0.05),与日间摄食指数差异极显著(P<0.01)。经Boostrap法抽样1000次检验,各组中位数均在其95%置信区间范围内,本次实验数据具代表性。研究表明,香螺是一种摄食范围广、摄食昼夜节律明显的腹足类动物。在人工养殖过程中,应当为其提供遮蔽物及弱光环境,以鱼类及甲壳动物为主要饵料组成部分,饵料聚集成堆于黄昏投喂,以提高其饵料利用率。

The feeding behavior of Neptunea arthritica cumingii was investigated using Crassostrea gigas,Artenria salina,Engraulis japonicus,and Argopecten irradians as diets through experimental ecological methods.The re-sults showed that N.arthritica cumingii fed by stretching out the muzzle and scraping the food with the radular teeth,and N.arthritica cumingii had a sense of diction when approaching the diet.N.arthritica cumingii could not directly lock onto the diet and needed a dark environment when eating.Furthermore,the study revealed that N.ar-thritica cumingii feeds on all four types of diet organisms;however,the feeding index for C.gigas reaches a statis-tically non-feeding level.The feeding index for E.japonicus was highest,reaching 0.290±0.040.However,no sig-nificant difference was observed compared to that of A.salina(P>0.05),and the feeding index for two bivalves was notably lower.Overall,the feeding preference order for diets was E.japonicus>A.salina>A.irradians>C.gigas.The feeding rhythm of N.arthritica cumingii was nocturnal,and they rarely fed during the daytime despite the availability of dietary organisms.Thus,the feeding index at night reached 0.672±0.011,which was different from that in the dawn/dusk and was significantly different from the feeding index in the daytime.After sampling 1000 times using the Bootstrap method,the median of each group was within its 95%confidence interval,indicat-ing the representation of the experimental data.These findings demonstrate that N.arthritica cumingii was a gas-tropod with a wide feeding range and a distinct nocturnal feeding rhythm.A shelter and a weak-light environment should be provided to improve the utilization rate of the diet,and fish and crustaceans should be used as the main components of the diet.Moreover,the diet should be gathered in piles,and evening could be the optimum feeding time in the artificial breeding process.