中文摘要：

2008年10月至2009年9月,对北部湾多齿蛇鲻逐月采样共749尾（实胃数408个）,通过胃含物分析法研究其摄食习性及随生长发育的变化。结果表明,北部湾多齿蛇鲻捕食种类包括鱼类、头足类以及虾类等饵料生物,其中可鉴定出的鱼类种类有17种。以相对重要性指数百分比为指标,鱼类为最主要饵料（98.8%）,其中优势饵料种类有蓝圆鲹（34.9%）、少鳞犀鳕（26.6%）、长颌棱鳀（4.30%）和条鲾（2.5%）。多齿蛇鲻摄食强度、饱满指数和成熟系数的月份差异十分显著,而以Brillouin指数表征的各月份营养多样性则无显著差异。一年中呈现3个产卵高峰期（3-4月、6月及11月）,产卵期间摄食强度没有降低,仍然强烈索饵。随着体长的增长,北部湾多齿蛇鲻饵料生物个数变化较小,但平均单个饵料生物质量却明显增加。聚类分析表明,北部湾多齿蛇鲻各体长组间食物组成相近,其中136～255mm各体长组相似性系数均大于60%。

英文摘要：

To advance the understanding of the diet of the greater lizardfish,Saurida tumbil（Bloch,1795） and its monthly and ontogenetic variations,an annual research was conducted from October 2008 to September 2009.Stomachs of 749 greater lizardfish,ranging in size from 124 mm to 375 mm in standard length（SL）,were sampled monthly in the Beibu Gulf of the South China Sea,and analysis of their stomach contents showed Decapterus maruadsi to be the primary prey components of the diet,averaging 9.7%by number,55.5%by weight and 34.9%by percentage of Index of Relative Importance（IRI）.Small benthic fish,Bregmaceros rarisquamosus and pelagic fish,Thryssa setirostris and Leiognathus riviulatus,with IRI percentages of 26.6%,4.3%and 2.5%,respectively were also relatively essential in the diet of this fish,whereas the other species of prey were only present in comparatively lower percentages.The research findings revealed that the mean repletion index and mean maturity coefficient varied considerably by month,while trophic diversity,calculated by Brillouin index Hz,proved to be relatively consistent throughout the year.Mean repletion index（RI） was highest（RI=7.61%） at the stage of Ⅵ-Ⅱ indicating that this group of greater lizardfish that reverted from Stage Ⅵ to StageⅡ increased their food input to compensate for energy loss during reproduction.On the other hand,the proportion of empty stomachs reached its peak with 61.5%while mean RI reached the second highest position with 5.98%at Stage Ⅴ,indicating that during the reproduction periods from March to April,and in June and November,greater lizardfish ceased feeding until digestion of the prior meal was completed or near completion.The 12 SL classes demonstrated significant differences with respect to prey weight but showed relative consistency in prey numbers.The tendency of mean prey weight increased the body size following with the improvement of the feeding organs and swimming ability of greater lizardfish.Using PRIMER 5.2 software,the cluster analysis