Aim Mapping the geographic distribution of non-native aquatic species is a critically important precursor to understanding the anthropogenic and environmental factors that drive freshwater biological invasions. Such efforts are often limited to local scales and/or to single species, due to the challenges of data acquisition at larger scales. Here, we map the distribution of non-native freshwater species richness across the continental United States and investigate the role of human activity in driving macro-scale patterns of aquatic invasion. Location The continental United States. Methods We assembled maps of non-native aquatic species richness by compiling occurrence data on exotic animal and plant species from publicly accessible databases. Using a dasymetric model of human population density and a spatially explicit model of recreational freshwater fishing demand, we analysed the effect of these metrics of human influence on the degree of invasion at the watershed scale, while controlling for spatial and sampling bias. We also assessed the effects that a temporal mismatch between occurrence data (collected since 1815) and cross-sectional predictors (developed using 2010 data) may have on model fit. Results Non-native aquatic species richness exhibits a highly patchy distribution, with hotspots in the Northeast, Great Lakes, Florida, and human population centres on the Pacific coast. These richness patterns are correlated with population density, but are much more strongly predicted by patterns of recreational fishing demand. These relationships are strengthened by temporal matching of datasets and are robust to corrections for sampling effort. Main conclusions Distributions of aquatic non-native species across the continental US are better predicted by freshwater recreational fishing than by human population density. This suggests that observed patterns are driven by a mechanistic link between recreational activity and aquatic non-native species richness and are not merely the outcome of sampling bias associated with human population density.

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休闲淡水捕捞推动大陆范围内的非本地水生物种丰富度模式

目的 绘制非本地水生物种的地理分布图是了解驱动淡水生物入侵的人为和环境因素的关键前兆。由于更大规模数据采集的挑战，此类努力通常仅限于局部规模和/或单一物种。在这里，我们绘制了美国大陆非本地淡水物种丰富度的分布图，并调查了人类活动在推动水生入侵宏观模式中的作用。位置 美国大陆。方法 我们通过从可公开访问的数据库中汇编外来动植物物种的出现数据来组装非本地水生物种丰富度的地图。使用人口密度的 dasymetric 模型和休闲淡水捕鱼需求的空间显式模型，我们分析了这些人类影响指标对流域范围内入侵程度的影响，同时控制了空间和采样偏差。我们还评估了发生数据（自 1815 年以来收集）和横截面预测变量（使用 2010 年数据开发）之间的时间不匹配可能对模型拟合的影响。结果 非本土水生物种丰富度呈现出高度零散分布，热点分布在东北部、五大湖区、佛罗里达州，人口集中在太平洋沿岸。这些丰富度模式与人口密度相关，但更能通过休闲捕鱼需求模式来预测。这些关系通过数据集的时间匹配得到加强，并且对采样工作的校正具有鲁棒性。主要结论 淡水休闲捕鱼比人口密度更能预测美国大陆水生非本地物种的分布。这表明观察到的模式是由娱乐活动和水生非本地物种丰富度之间的机械联系驱动的，而不仅仅是与人口密度相关的抽样偏差的结果。