中国水产科学2025，Vol.32Issue(9)：1344-1355,12.DOI:10.12264/JFSC2025-0129
禁捕后长江口棘头梅童鱼食性特征
Trophic characteristics of Collichthys lucidus in Yangtze River Estuary under fishing ban
摘要
Abstract
This study investigated the dietary composition of Collichthys lucidus in the Yangtze River Estuary during the post-fishing moratorium period through stomach content analysis of specimens collected in spring 2024.Statistical analyses revealed that the diet comprised 29 prey species from 11 taxonomic groups,with crustaceans(shrimps and crabs)dominating as the primary food source,accounting for 96.32%of the index of relative importance(IRI%)(shrimps:32.78%;crabs:63.54%).Significant ontogenetic niche differentiation in prey selection was observed between juveniles and adults(P<0.01).Juvenile fish primarily consumed Eriocheir leptognathus(IRI%=38.55%)and the Acanthomysis longirostris(IRI%=23.12%),while adults showed preference for megalopa larvae of Eriocheir sinensis(IRI%=54.76%)and Exopalaemon annandalei(IRI%=27.67%).These ontogenetic dietary shifts can be explained by optimal foraging theory,where fish optimize energy acquisition by balancing energy gain against expenditure.As body size increases,the feeding strategy shifts toward larger prey items to meet higher energy demands and improve feeding efficiency.Spatial analysis demonstrated significant regional variations in dietary composition(P<0.05).The freshwater zone was dominated by Exopalaemon annandalei(IRI%=73.65%),while the brackish water region showed preference for Eriocheir sinensis megalopa(IRI%=54.17%)and Exopalaemon annandalei(IRI%=22.86%).The observed increase in cannibalism frequency from 0.4%(pre-moratorium)to 2.5%(post-moratorium)suggests intensified intraspecific competition,likely due to population density increases and food scarcity,potentially forcing less competitive individuals to migrate from brackish to freshwater zones for foraging.Comparative analysis revealed significant post-moratorium dietary changes,with a 66.6%turnover rate among dominant prey species,possibly reflecting ecological restructuring due to altered competitive pressures in the estuarine ecosystem.Notably,our results indicate no feeding preference for Eriocheir sinensis megalopa in C.lucidus,but rather reveal density-dependent feeding suppression.This phenomenon may result from either collective defense mechanisms of megalopa larvae or alternative prey preferences in C.lucidus,warranting further investigation. These findings provide crucial baseline data for understanding trophic dynamics in the Yangtze Estuary ecosystem and evaluating the ecological effects of fishing moratorium policies,while highlighting the need for continued monitoring of predator-prey interactions under changing environmental conditions.关键词
长江口/棘头梅童鱼/食物组成/胃含物分析Key words
Yangtze River Estuary/Collichthy lucidus/food composition/stomach contents analysis分类
农业科技引用本文复制引用
SHU Chuanjun,TANG Zeping,ZHANG Tao,GENG Zhi,ZHAO Feng,YANG Gang,ZHUANG Ping..禁捕后长江口棘头梅童鱼食性特征[J].中国水产科学,2025,32(9):1344-1355,12.基金项目
中国水产科学研究院中央级公益性科研院所基本科研业务专项资金项目(2024XT1001) （2024XT1001）
国家自然科学基金项目(32102800) （32102800）
上海市社会发展科技攻关项目(22dz1202703) （22dz1202703）
上海市生态环境局科研项目(沪环科[2023]第5号). （沪环科[2023]第5号）
