Increasing human population size and mobility have accelerated the translocation of nonnative species globally, which has become a major threat to conservation of biodiversity and ecosystem services. Introduced species can disrupt species interactions of the recipient ecosystem, triggering system‐wide events, and amplify or dampen effects of existing pressures. We show how two pervasive intercontinental invasive consumers in North American lakes, dreissenids (filter‐feeding mussels) and Bythotrephes (carnivorous zooplankton), nonlinearly modify consumer–resource dynamics and undermine management interventions to rebuild cold‐water predatory fish biomass. Synthesizing 30 yr (1986–2015) of lake‐wide monitoring data with a dynamic mass‐balance food‐web model (consisting of 61 species and trophic groups), we reconstructed historical food‐web dynamics of Lake Simcoe, a large, temperate lake in Ontario, Canada that has shifted from a turbid to clear‐water state. We then analyzed patterns of biomass fluctuations of three recreationally harvested, ecologically connected populations; lake trout (Salvelinus namaycush, a piscivore), lake whitefish (Coregonus clupeaformis, a benthivore), and cisco (C. artedi, a planktivore) before and after the invasions by testing hypotheses on their delayed recoveries under management interventions–predator manipulations (fishery removal and stocking) and nutrient (phosphorus) load reduction. Analyses suggest that fishery harvest primarily regulated early recovery trajectories of the piscivore and planktivore, weakening top‐down control prior to the establishment of the invasive consumers. By contrast, the benthivore biomass patterns were shaped, in part, by the invasive mussels (via diet shift), independently of management actions. Although improved water quality (with reduced hypoxia in deeper water) and, in turn, higher macrophyte production are projected to expand the predation refuge for young fish, intensified planktivory (by Bythotrephes) and herbivory (by dreissenids) have triggered shifts in community composition (from pelagic to demersal dominance). These system‐wide shifts, in turn, have substantially diminished ecosystem productivity, thereby shrinking fishery yields. Novel consumers can rewire food webs, disrupt energy flows, and suppress predator recoveries, underscoring the need to account for altered ecological reality when sustainably managing fishery resources in invaded ecosystems.

中文翻译：

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生物入侵后对渔业生态系统动力学的转移营养控制。

人口规模的增加和流动性的增加，加速了全球外来物种的迁移，这已成为保护生物多样性和生态系统服务的主要威胁。引进的物种可能会破坏受体生态系统的物种相互作用，引发全系统事件，并放大或减弱现有压力的影响。我们展示了北美湖泊中两个普遍存在的洲际侵入性消费者，地雷类（滤食贻贝）和比索菲斯（食肉性浮游动物），非线性地改变了消费者-资源的动态，破坏了管理措施来重建冷水掠食性鱼类生物量。利用动态质量平衡食物网模型（由61个物种和营养类组成）对30年（1986-2015年）的全湖监测数据进行了综合，我们重建了温带大湖Simcoe的历史食物网动态。在加拿大的安大略省，已经从浑浊的州转变为清水州。然后，我们分析了三个休闲采集的，生态相关的种群的生物量波动模式；鳟鱼（Salvelinus namaycush，食肉动物），白鲑湖（Coregonus clupeaformis，底栖动物）和思科（C. artedi，在入侵之前和之后，通过在管理干预措施（捕食者操纵（捕捞和放养）和养分（磷）负荷减少）下检验其延迟恢复的假设来检验入侵。分析表明，渔业捕捞主要调节食草动物和浮游动物的早期恢复轨迹，削弱了在建立侵入性消费者之前的自上而下的控制。相比之下，底栖动物的生物量模式部分地由侵入贻贝（通过饮食转变）形成，与管理行为无关。尽管改善了水质（减少了深层缺氧的程度），进而提高了大型植物的生长，预计将扩大幼鱼的捕食避难所，但浮游动物的数量会增加（by Bythotrephes））和草食性动物（由纤毛虫引起）触发了群落组成的转变（从上层到上层优势）。反过来，这些全系统的转变大大降低了生态系统的生产力，从而降低了渔业产量。新型消费者可以重新连接食物网，破坏能量流并抑制捕食者的恢复，从而强调了在可持续管理入侵的生态系统中的渔业资源时，必须考虑到生态现实的变化。