2010年6月在福建省官井洋海域收集579尾大黄鱼(lArIMICHTHyS CrOCEA)标本进行胃含物分析,同步采集取样点附近水域浮游动物及张网样品,比较大黄鱼胃含物种类与水域中生物种类组成的相似性。结果表明:大黄鱼食物种类共32种,种类广泛。大黄鱼主要摄食十足类(相对重要性指标百分比%IrI=49.14%)、鱼类(%IrI=20.47%)、磷虾类(%IrI=18.31%)和糠虾类(%IrI=2.34%),具有以游泳动物、浮游动物为主要食物对象的肉食性摄食习性。细螯虾(lEPTOCHElA grACIlIS)(相对重要性指标IrI=976.10,%IrI=35.38%)和中华假磷虾(PSEudEuPHAuSIA SInICA)(IrI=505.27,%IrI=18.31%)为大黄鱼食物组成中最重要的食物种类。海区中,浮游动物以桡足类为主,占所有浮游动物总丰度的45.03%,主要优势种为太平洋纺锤水蚤(ACArTIA PACIfICA,优势度y=0.14)、双刺唇角水蚤(lAbIdOCErA bIPInnATA,y=0.09)和中华哲水蚤(CAlAnuS SInICuS,y=0.06);张网渔获物共鉴定91种,主要为细螯虾、白姑鱼(ArgyrOSOMuS ArgEnTATuS)、大黄鱼(lArIMICHTHyS CrOCEA)蟳、双斑(CHArybdIS bIMACulATA)、三疣梭子蟹(POrTunuSTrITubErCulATuS)、银鲳(PAMPuS ArgEnTEuS)鮻和棱(lIzA CArInATuS)。研究表明,大黄鱼对食物种类具有明显的选择性,主要体现在喜好追逐捕食海区中的小型虾类和仔、稚、幼鱼以及体型相对较大的浮游动物磷虾类和糠虾类。The population of large yellow croaker(Larimichthys crocea) has declined since the 1970s.Despite the decline,little is known about the feeding behavior and diet of this species.Our objective was to document the dietary composition of large yellow croaker.We collected 579 specimens from the sea near Guanjing Yang,Fujian province during June 2010.We documented the stomach contents of each individual and calculated the occurrence frequency(F%),individual number percentage(N%),weight percent(W%),and an index of relative importance(IRI).In addition,we compared diet composition of the zooplankton and nektonic assemblages in the ambient water.We identified 32 species in the diet.The most abundant were decapoda,fish,euphausiacea,mysidacea,amphipoda,crabs,copepoda,and stomatopoda.Decapoda(%IRI=49.14%) and fish(%IRI=20.47%) were the most important prey groups in the diet.Euphausiacea(%IRI=18.31%) and Mysidacea(%IRI=2.34%) constituted the second most important prey groups.Leptochela gracilis(IRI=976.10,%IRI=35.38%) and Pseudeuphausia sinica(IRI=505.27,%IRI=18.31%) were the most important prey species.Our data suggest that the large yellow croaker is carnivorous and feeds primarily on decapods,fish,and macro zooplankton.The trophic level of the wild large yellow croaker is lower than nektonic-animal feeders but higher than planktonic-animal feeders.The dominant species of the zooplankton assemblage was copepoda,primarily Acartia pacifica(Y=0.14),Labidocera bipinnata(Y=0.09),and Calanus sinicus(Y=0.06).The percent mean abundance of Euphausiacea and Mysidacea was 0.83%.Fish,crabs,and decapods were the most abundant nektonic organisms.We hypothesize that the large yellow croaker exhibits selectivity for food,preferring small decapods,fish larvae,euphausiacea,and mysidacea to other groups.国家自然基金项目(40776047);973计划项目(2010CB428705
