Data from: Interpreting and predicting the spread of invasive wild pigs

The eruption of invasive wild pigs (IWPs) Sus scrofa throughout the world exemplifies the need to understand the influences of exotic and non-native species expansions. In particular, the continental USA is precariously threatened by a rapid expansion of IWPs, and a better understanding of the rate and process of spread can inform strategies that will limit the expansion. We developed a spatially and temporally dynamic model to examine three decades (1982–2012) of IWP expansion, and predict the spread of IWPs throughout the continental USA, relative to where IWPs previously inhabited. We used the model to predict where IWPs are likely to invade next. The average rate of northward expansion increased from 6.5 to 12.6 km per year, suggesting most counties in the continental USA could be inhabited within the next 3–5 decades. The spread of IWPs was primarily associated with expansion into areas with similar environmental characteristics as their previous range, with the exception of spreading into colder regions. We identified that climate change may assist spread into northern regions by generating milder winters with less snow. Otherwise, the spread of IWPs was not dependent on agriculture, precipitation, or biodiversity at the county level. The model correctly predicted 86% of counties that were invaded during 2012, and those predictions indicate that large portions of the USA are in immediate danger of invasion. Synthesis and applications. Anti-invasion efforts should focus along the boundaries of current occupied range to stop natural expansion, and anti-invasion policies should focus on stopping anthropogenic transport and release of invasive wild pigs (IWPs). Our results demonstrate the utility of a spatio-temporal examination to inform strategies for limiting the spread of IWPs.全球范围内入侵性野猪（Invasive Wild Pigs, IWPs，学名*Sus scrofa*）的入侵暴发现象，凸显了深入探究外来非本土物种扩张影响的迫切需求。其中，美国本土正面临入侵性野猪快速扩张带来的严峻威胁，明晰其扩散速率与过程，可为制定遏制扩张的防控策略提供科学依据。 本研究构建了时空动态模型，以1982年至2012年共30年的入侵性野猪扩张观测数据为基础，结合其既往栖息分布，模拟并预测了美国本土范围内的入侵性野猪扩散趋势，并进一步预判了下一波潜在入侵区域。 研究结果显示，入侵性野猪北向扩张的平均速率从每年6.5公里提升至12.6公里，这意味着未来30至50年内，美国本土绝大多数县或将被入侵野猪占据。其扩散主要倾向于选择与既往栖息环境特征相似的区域，但向寒冷地区的扩散属于例外。本研究证实，气候变化或通过造就更温和的冬季、减少积雪覆盖，助力野猪向北部区域扩张。除此之外，在县级尺度下，野猪的扩散与农业发展、降水条件或生物多样性并无显著关联。该模型对2012年新增入侵县的预测准确率达86%，预测结果显示美国大片区域正面临即时的入侵风险。 综合与应用。入侵防控工作应聚焦于当前已占据区域的边界地带，以阻断其自然扩散；而防控政策则应着力遏制人为运输与释放入侵性野猪的行为。本研究结果证实，时空动态分析可为限制入侵性野猪扩散的防控策略提供有效支撑。