Feeding and Trophic Ecology of Invasive Blue Catfish Ictalurus furcatus in an Eastern shore tributary of the Chesapeake Bay

This study investigates the feeding and trophic ecology of invasive Blue Catfish (Ictalurus furcatus) in the Nanticoke River watershed on the Chesapeake Bay’s Eastern Shore (Maryland, U.S.A). From a total of 1,032 stomach samples collected, a subset of 88 was analyzed using 18S and COI metabarcoding primers to enhance taxonomic resolution of prey items. USGS-generated genetic reference data enabled the identification of diet components that were unidentifiable through traditional morphological methods. The metabarcoding results revealed diverse prey assemblages, including seasonally available and ecologically significant species such as Alosa spp., Callinectes sapidus, and Morone americana. These findings support evidence of ontogenetic dietary shifts and highlight the value of molecular tools in understanding invasive predator impacts. This research contributes to interjurisdictional fisheries management and invasive species control efforts in the Chesapeake Bay.

本研究针对美国马里兰州切萨皮克湾东岸楠蒂科克河流域的入侵物种蓝鲶（Ictalurus furcatus）的摄食与营养生态开展调查。研究共采集1032份胃容物样本，选取其中88份采用18S与COI元条形码（metabarcoding）引物进行分析，以提升猎物类群的分类鉴定分辨率。美国地质调查局（USGS）生成的遗传参考数据，助力研究者鉴定出传统形态学方法无法识别的食物组分。元条形码分析结果显示猎物类群组成多样，涵盖季节性出现且具有重要生态意义的物种，如西鲱属（Alosa spp.）、蓝蟹（Callinectes sapidus）与美洲白鲈（Morone americana）。本研究结果为个体发育食性转变提供了佐证，并凸显了分子工具在解析入侵捕食者生态影响中的应用价值。该研究可为切萨皮克湾跨辖区渔业管理与入侵物种防控工作提供科学支撑。