Canadian Journal of Fisheries and Aquatic Sciences, Ahead of Print.
Conceptually, trophic niche overlap and species abundance can describe the strength and number of interspecific trophic interactions to determine the competitive impact on reintroduced species or other ecosystem changes. We use an example with young-of-year (YOY) Atlantic salmon (Salmo salar) reintroductions to determine whether trophic niche overlaps and abundances limit restoration success. Using seasonal stable isotopes and abundance estimates for invertivorous fishes in three Lake Ontario tributaries, we assessed community isotopic structure, trophic niche overlap, and the impact of the niche overlap by incorporating relative abundance. Brown trout (Salmo trutta) YOY could be a strong competitor with a high trophic niche overlap with Atlantic salmon YOY, but at lower abundances relative to Atlantic salmon there is minimal impact. Stream resident fish communities appeared to partition resources across seasons such that abundant species had low trophic niche overlap to minimize overall competition with Atlantic salmon YOY given available resources, indicating niche complementarity. Through joint consideration of trophic overlap and abundance using our conceptual model, the competitive impact of community composition on a reintroduced species could be assessed.

中文翻译：

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营养生态位的重叠和丰度揭示了种间相互作用对再引入鱼类的潜在影响

《加拿大渔业和水生科学杂志》，印刷前。
从概念上讲，营养位的重叠和物种丰富度可以描述种间营养相互作用的强度和数量，以确定对再引入物种或其他生态系统变化的竞争影响。我们以年少（YOY）的大西洋鲑（Salmo salar）重新引入为例，确定营养小生境是否重叠和丰度限制恢复成功。我们使用三个安大略湖支流的非连续性鱼类的季节性稳定同位素和丰度估算，通过纳入相对丰度来评估群落同位素结构，营养生态位重叠以及生态位重叠的影响。褐鳟（Salmo trutta）可能是强劲的竞争者，与大西洋鲑相比其营养位高，但与大西洋鲑相比，其丰度较低，影响很小。溪流常驻鱼类群落似乎跨季节分配资源，使得丰富的物种具有低营养位生态位重叠，从而在给定可用资源的情况下最大程度地减少了与大西洋鲑YOY的总体竞争，表明了生态位的互补性。通过使用我们的概念模型共同考虑营养重叠和丰度，可以评估群落组成对再引入物种的竞争影响。