荣成俚岛大泷六线鱼摄食生态研究

为研究荣成俚岛大泷六线鱼的摄食生态,于2010年3月—2011年2月逐月采集荣成俚岛近海482尾大泷六线鱼,对其进行胃含物分析。结果发现,大泷六线鱼为底栖生物食性鱼类摄食的饵料生物有10个类群,主要摄食鱼类,其次是多毛类、虾类、海藻类、蟹类和口足类等。食物组成随季节和体长而变化:除四季均大量摄食虾类外,春季还摄食蟹类和多毛类,夏季和秋季主要摄食鱼类,冬季摄食多毛类的比例最高;体长80 mm的大泷六线鱼喜食虾类和端足类,体长80~119 mm个体喜食多毛类、口虾蛄幼体和虾类等,而体长119 mm个体主要摄食鱼类、虾蟹类。摄食强度也随季节和体长而变化:夏季摄食强度最高,冬季最低(不停食);体长80 mm个体摄食强度最高,随体长增加摄食强度逐渐下降,体长180 mm以上的个体又随体长、年龄的增大而逐渐升高。通过DNA条形码对大泷六线鱼的6个饵料生物样品进行鉴定,其中,4个饵料生物样品鉴定到种,1个样品鉴定到属,1个样品鉴定到科。

Feeding ecology of Hexagrammos otakii in Lidao Rongcheng

The studies on feeding ecology of fish are the basis for understanding the function of the whole community and ecosystem,and they will also contribute to the fisheries management.DNA barcoding is a new way to study the stomach contents,and it will also improve accuracy of the results on dietary composition by combining with morphological analysis.Hexagrammos otakii is an important commercial fish and possesses potential in aquaculture industry.Stomach contents analysis of H.otakii was investigated based on 482 individuals collected monthly from the shore reef of Lidao Rongcheng between March 2010 and February 2011.The main results were as follows:H.otakii was the demersal-feeding fish.Among the 10 prey groups,fish was the dominant prey group,and they also included polychaeta,decapoda,algae,crabs and stomatopoda,etc.The dietary composition had obvious seasonal variations:decapoda was the important prey group in every season,crabs and polychaeta in spring,fish in summer and autumn,and polychaeta were mostly in winter.The dietary composition also had obvious ontogenetic variations:<80 mm SL preyed on decapoda and amphipoda;80-119 mm SL preyed on polychaeta,stomatopoda larvae and decapoda;>119 mm SL preyed on fish,decapoda and crabs.The feeding intensity had obvious seasonal variations,with highest in summer and lowest in winter.The feeding intensity also had obvious ontogenetic variations,reached the highest feeding intensity in <80 mm SL,then decreased with increasing standard length,and gradually increased after >180 mm SL.Six samples could be identified based on DNA barcoding,among which,four samples were identified as species,other two samples were identified as genus and family respectively.