The oriental river shrimp (Macrobrachium nipponense), an exotic species, has been well adapted and dispersed in Iranian freshwater ecosystems. The feeding ecology and trophic level of this species in the Anzali Wetland, southwestern Caspian Sea, was investigated by both a traditional method and the carbon and nitrogen stable isotope technique. The highest feeding index (FI) was seen in mollusca at 35.9%, followed by detritus at 31.3%. While no significant differences were observed in the preference of food items among different seasons. A Bayesian mixing model was used to estimate the contributions of the stomach contents to the isotopic signature of M. nipponense. According to mixing model results, M. nipponense obtain food from gastropod, fish, shrimp (as cannibalism), insecta, other crustacea, aquatic plants, worms, zooplankton, and unrecognizable content (as detritus) with 30.6%, 16.8%, 12.7%, 5.2%, 4.3%, 3.5%, 0.6%, 0.3%, and 25.9%, respectively. M. nipponense showed a high δ¹⁵N and its trophic level (TL = 3.38) was at the top of the Anzali Wetland food web, close to commercially important fish species such as pike, Esox Lucius. Being at this trophic level, this shrimp is expected to possess high nutritional quality for human consumption.

东方河虾（Macrobrachium nipponense）是一种外来物种，已经很好地适应并散布在伊朗的淡水生态系统中。通过传统方法和碳氮稳定同位素技术研究了该物种在里海西南部安扎里湿地的摄食生态学和营养水平。软体动物的最高进食指数（FI）为35.9％，其次是碎屑，为31.3％。虽然在不同季节之间对食物的偏好没有观察到显着差异。贝叶斯混合模型用于胃内容物的贡献估计到的同位素特征日本沼虾。根据混合模型结果，M。nipponense从腹足动物，鱼类，虾类（食人动物），昆虫，其他甲壳纲，水生植物，蠕虫，浮游动物和不可识别的成分（如碎屑）中获取食物，其比例分别为30.6％，16.8％，12.7％，5.2％，4.3％，3.5％ ，0.6％，0.3％和25.9％。日本沼虾显示出高的δ ¹⁵ N和它的营养水平（TL = 3.38）是在湿地安扎食物网的顶部，靠近重要商业价值的鱼类如狗鱼，白斑狗鱼。由于处于这种营养水平，预计该虾具有高营养品质，可供人类食用。