Portunid crabs contribute to significant commercial and recreational fisheries globally and are commonly fished in estuaries and/or marine embayments, which are amongst the most degraded of all aquatic ecosystems. Portunus armatus were collected seasonally between April and February from five locations across three systems in temperate south-western Australia. The dietary composition of crabs was quantified and compared between two estuaries (Peel-Harvey and Swan-Canning) and a sheltered marine embayment (Cockburn Sound) containing three distinct habitats: shallow seagrass, shallow sand and deep sand. Overall, crabs ingested large volumes of bivalves (both live organisms and dead shell), polychaetes, crustaceans (e.g., amphipods, small decapods), and smaller volumes of teleosts, echinoderms and plant material (seagrass, algae). Analysis of Similarities showed that dietary composition varied significantly among the five locations (two estuaries and three habitats within Cockburn Sound) and seasons, with greater location than seasonal differences in the two estuaries. Diets were most distinct in the Cockburn Sound seagrass due to greater volumes of decapods and teleosts and smaller volumes of bivalve shell consumed in this habitat. Crabs from both estuaries consumed greater quantities of bivalves than those from Cockburn Sound. Seasonal differences in both estuaries were greatest between summer and winter, with a more diverse range of prey and large quantities of bivalves ingested in summer, whereas small bivalves and bivalve shell in the Peel-Harvey and polychaetes and other crustaceans in the Swan-Canning, were consumed in greater quantities in winter. The summer diet in the Peel-Harvey Estuary in the current study was compared to that 20 years previous and with documented change in the benthic macroinvertebrate fauna. Currently, crabs consume smaller volumes of high-calorie prey, i.e., polychaetes, small bivalves and teleosts, and instead ingest greater proportions of calcareous material than previously. This marked shift in dietary composition parallels changes in benthic macroinvertebrates in the Peel-Harvey Estuary. Overall, prey availability appears to be the major factor influencing the spatial and temporal differences in P. armatus diets in these three coastal systems.

Portunid螃蟹为全球重要的商业和休闲渔业做出了贡献，通常在河口和/或海洋隔离带捕鱼，这是所有水生生态系统中退化最严重的一个。 臭豆在4月至2月期间，季节性采集来自澳大利亚西南温带地区三个系统的五个地点。对蟹的饮食成分进行了量化，并在两个河口（Peel-Harvey和Swan-Canning）和一个带有三个不同生境的避风港（Cockburn Sound）之间进行了比较：浅海草，浅沙和深沙。总体而言，螃蟹摄入了大量的双壳类动物（活生物体和死壳），多毛类，甲壳类动物（例如，两栖类，小型足类）和较小量的硬骨鱼，棘皮动物和植物材料（海草，藻类）。相似性分析表明，五个地点（科克本峡内的两个河口和三个栖息地）和季节之间的饮食构成存在显着差异，而两个河口的饮食结构比季节差异更大。考克本峡海草的饮食最独特，这是因为该栖息地中的十足纲和硬骨鱼类数量较多，而双壳类贝壳的消费量较小。来自两个河口的螃蟹消耗的双壳类动物数量要多于来自科本湾的螃蟹。夏季和冬季，这两个河口的季节差异最大，夏季捕食的捕食者种类更多，而在皮尔-哈维（Peel-Harvey）的小型双壳类和双壳类壳以及天鹅罐头中的多壳类和其他甲壳类动物，在冬天被大量消耗。本研究将皮尔-哈维河口的夏季饮食与20年前的夏季饮食进行了比较，并记录了底栖大型无脊椎动物动物群的变化。目前，螃蟹消耗的热量较小，即高毛猎物，即多毛et，小的双壳类和硬骨鱼类，取而代之的是摄取比以前更大比例的钙质物质。饮食组成的这种明显变化与皮尔-哈维河口底栖大型无脊椎动物的变化平行。总体而言，猎物的可用性似乎是影响捕食者时空差异的主要因素。armatus 这三个沿海系统的饮食。