Data for: Generalist invasion in a complex lake food web

Invasive species constitute a threat not only to native populations but also to the structure and functioning of entire food webs. Despite being considered as a global problem, only a small number of studies have quantitatively predicted the food web‐level consequences of invasions. Here, we use an allometric trophic network model parameterized using empirical data on species body masses and feeding interactions to predict the effects of a possible invasion of Amur sleeper (Perccottus glenii), on a well‐studied lake ecosystem. We show that the modeled establishment of Amur sleeper decreased the biomasses of top predator fishes by about 10%–19%. These reductions were largely explained by increased larval competition for food and Amur sleeper predation on fish larvae. In contrast, biomasses of less valued fish of lower trophic positions increased by about 0.5%–9% owing to reduced predation pressure by top piscivores. The predicted impact of Amur sleeper establishment on the biomasses of native fish species vastly exceeded the impacts of current‐day fishing pressures.

外来入侵物种不仅对本土种群构成威胁，还会损害整个食物网的结构与生态功能。尽管入侵物种问题已被视为全球性议题，但目前仅有少量研究从定量角度预测了入侵事件对食物网尺度的影响。本研究借助基于物种体重与取食相互作用实测数据完成参数化的异速生长营养网络模型（allometric trophic network model），针对一处已被广泛研究的湖泊生态系统，预测葛氏鲈塘鳢（Amur sleeper, Perccottus glenii）的潜在入侵所带来的生态效应。研究结果显示，模拟的葛氏鲈塘鳢定殖过程会使顶级掠食性鱼类的生物量下降约10%~19%，该降幅主要源于两方面因素：一是鱼类幼体间的食物竞争加剧，二是葛氏鲈塘鳢对鱼类幼体的捕食压力提升。与之相对，由于顶级食鱼性鱼类的捕食压力降低，营养层级较低、经济价值欠佳的鱼类生物量提升了约0.5%~9%。葛氏鲈塘鳢定殖对本土鱼类生物量的预测影响，远超当前渔业捕捞活动所带来的生态效应。