Liu Fei, Wang Jianwei, Liu Huanzhang
The Key Laboratory of Aquatic Biodiversity and Resource Conservation, Institute of Hydrobiology Chinese Academy of Science Wuhan Hubei Province China.
Ecol Evol. 2019 May 28;9(12):7227-7236. doi: 10.1002/ece3.5293. eCollection 2019 Jun.
Knowledge of food resource partitioning among sympatric fish species is crucial for understanding the potential mechanisms of species coexistence. Gudgeons (Teleostei: Cyprinidae: Gobioninae) often dominate fish assemblages in the upper Yangtze River. However, little research has been conducted on their trophic interactions. In this paper, seasonal diet and feeding strategy variations of four sympatric gudgeon species, , , and , were investigated by analysis of intestinal tract contents, aiming to explore whether food resource partitioning occurred among them. Fish specimens were collected during spring (April-May) and autumn (August-October) in 2010 in Hejiang, a free-flowing stretch of the upper Yangtze River. , and showed omnivorous feeding habits, while exhibited an obligate carnivore feeding habit. Diet overlap among the four studied species was high, especially in spring. However, changes in feeding strategies were observed in autumn. Specifically, and expanded their dietary niche breadth and consumed detritus, Sinopotamidae or Hydropsychidae as important complementary food resources. In contrast, and reduced their dietary niche breadth and became more specialized on mussels (). These results confirmed that sympatric fish species can coexist with high diet overlap, and food resource partitioning among these species may also fluctuate with the seasons.
了解同域分布鱼类物种间的食物资源分配情况对于理解物种共存的潜在机制至关重要。吻鮈（硬骨鱼纲：鲤科：鮈亚科）通常在上游长江的鱼类群落中占主导地位。然而，关于它们的营养相互作用的研究却很少。在本文中，通过对肠道内容物的分析，调查了四种同域分布的吻鮈物种，即[物种1]、[物种2]、[物种3]和[物种4]的季节性饮食和摄食策略变化，旨在探究它们之间是否存在食物资源分配。2010年春季（4月至5月）和秋季（8月至10月）在长江上游一段未筑坝的合江江段采集了鱼类标本。[物种1]、[物种2]和[物种3]表现出杂食性摄食习性，而[物种4]表现出专性肉食性摄食习性。在所研究的四个物种中，饮食重叠度很高，尤其是在春季。然而，在秋季观察到了摄食策略的变化。具体而言，[物种1]和[物种2]扩大了它们的饮食生态位宽度，并将碎屑、河蚬科或纹石蛾科作为重要的补充食物资源。相比之下，[物种3]和[物种4]缩小了它们的饮食生态位宽度，并变得更加专食贻贝（[贻贝学名]）。这些结果证实，同域分布的鱼类物种可以在高饮食重叠的情况下共存，并且这些物种之间的食物资源分配也可能随季节波动。
