Insights into the food habits of predators are essential for maintaining healthy predator populations and the functioning of ecosystems. Stomach content and stable isotope analyses were used to investigate the foraging habits of an apex predator, the Indo-Pacific bottlenose dolphin (Tursiops aduncus) in south-western Australia. A total of 2,594 prey items from 26 families were identified from the stomachs of 10 deceased stranded dolphins. Fish otoliths from stomach contents were used to identify fish to family or species level. Ninety-three percent of identified stomach contents were perciforme fishes, however, perciformes comprised only 30% of the catch during prey sampling. Gobiidae species, small fish generally <100 mm in total length, were the most prevalent family identified in dolphin stomachs, accounting for 82% of identified prey, yet Gobiidae accounted for 12.7% of the catch during prey sampling. For stable isotope analyses, tissue samples from 14 free-ranging dolphins were analyzed for nitrogen (δ¹⁵N) and carbon (δ¹³C) ratios. From stable isotope analyses and boat-based dolphin photo-identification surveys (n = 339, 2007–2011), results indicated niche differentiation between coastal and inshore (bay and estuarine habitat) dolphins. Carbon signatures showed that coastal dolphins had a more pelagic diet compared to a benthic diet observed in the inshore dolphins. Whereas, nitrogen signatures of inshore dolphins showed higher nitrogen levels than coastal dolphins, likely attributed to feeding on enriched prey typical of estuarian environments. Overall, these results indicated that bottlenose dolphins in the study area were selective foragers and that their foraging is specialized by the habitats most frequently used.

洞察捕食者的饮食习惯对于维持健康的捕食者种群和生态系统的功能至关重要。胃内容物和稳定的同位素分析被用来调查一种尖牙捕食者印度-太平洋宽吻海豚（Tursiops aduncus）的觅食习性）在澳大利亚西南部。从10只死去的搁浅海豚的胃中鉴定出来自26个家庭的总共2,594个猎物。胃内容物中的鱼耳石被用来识别鱼类的家族或物种水平。识别出的胃内容物中有百分之九十三是鲈鱼，但是在捕食者中，鲈鱼只占捕获量的30％。在海豚胃中发现的最普遍的科目是戈壁科物种，通常总长度小于100毫米，占所发现猎物的82％，而在猎物采样期间，戈壁科占捕获量的12.7％。对于稳定同位素分析，从14自由测距海豚组织分析样品的氮（δ ¹⁵ N）和碳（δ ¹³C）比率。通过稳定的同位素分析和基于船的海豚照片鉴定调查（n = 339，2007–2011），结果表明沿海和近海（海湾和河口栖息地）海豚之间的生态位差异。碳特征表明，与在近海海豚中观察到的底栖食物相比，沿海海豚的食物中上层食物含量更高。相比之下，近海海豚的氮签名显示出比沿海海豚更高的氮含量，这很可能是由于以河口环境中典型的丰富猎物为食。总体而言，这些结果表明，研究区的宽吻海豚是选择性觅食者，它们的觅食是最常用的栖息地的专门化。