Estuaries present a set of unique challenges for freshwater fish. In addition to basic physiological challenges, the influx of salinity can affect prey availability and can influence resource consumption. Diets of coastal Largemouth Bass Micropterus salmoides were surveyed from three sites in the Mobile Bay estuary, Alabama, USA, from April 2011 to April 2015. A large proportion of Largemouth Bass consumed blue crabs Callinectes sapidus (proportion occurrence [PO] = 0.38) and mud crabs Panopeus spp. (PO = 0.24). Largemouth Bass also consumed grass shrimp Palaemonetes spp. (PO = 0.16), Gulf Menhaden Brevoortia patronus (PO = 0.14), and mysid shrimp Mysidopsis spp. (PO = 0.12). Prey diversity was greater at the lower estuary site (Fowl River) than at the sites in the upper estuary (Bay Minette and D'Olive Bay). A principal components analysis based on the biomass diet data revealed that invertebrates were the most important prey resource for coastal Largemouth Bass, with finfishes playing a secondary role. Seasonal inputs of estuarine fish species, such as Gulf Menhaden, represented an important prey resource in the diets of Largemouth Bass during both spring and summer.

中文翻译：

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边缘的淡水捕食者：评估美国阿拉巴马州莫比尔湾河口大嘴鲈饮食中的时空变化

河口给淡水鱼带来了一系列独特的挑战。除了基本的生理挑战外，盐分的涌入还会影响猎物的可利用性并可能影响资源的消耗。2011年4月至2015年4月，从美国阿拉巴马州莫比尔湾河口的三个地点调查了沿海大嘴鲈微鲑鱼的饮食。大嘴鲈食用蓝蟹Callinectes sapidus（比例发生[PO] = 0.38）和泥蟹Panopeus spp。（PO = 0.24）。大嘴鲈鱼还食用草虾Palaemonetes spp。（PO = 0.16），墨西哥湾Menhaden Brevoortia patronus（PO = 0.14）和Mysid虾Mysidopsisspp。（PO = 0.12）。河口下游地区（福尔河）的猎物多样性大于河口上游地区（贝内特湾和德奥利夫湾）的猎物多样性。根据生物质饮食数据进行的主成分分析表明，无脊椎动物是沿海大嘴鲈最重要的猎物资源，其中有鳍鱼扮演次要角色。春季和夏季，河口鱼类（例如墨西哥湾海港）的季节性投入是大嘴鲈鱼饮食中的重要猎物资源。