What factors govern the rate of spread of an invasive species? Assessing the importance of dispersal and selection in range expansion

在这个项目中，数学模型和遗传分析结合实验和实地调查，以更好地预测入侵铁杉绵蚜（Adelges tsugae， HWA）在美国东部的传播。这种森林害虫杀死东部铁杉，并造成经济和生态破坏。遗传标记将用于鉴定不同的HWA无性系，每个无性系将测量其传播率，群体增长率和耐寒性。这些信息将与报告入侵种群遗传结构的调查数据结合使用，以建立一个数学模型，研究在寒冷冬季条件下生存的分散和选择在推动HWA范围扩大中的作用。这项研究将大大增加对入侵物种如何在景观中传播的理解。铁杉在经济和文化上都很重要，它们的消失引起了从林业官员到当地居民的广泛关注。了解HWA如何以及为什么在整个景观中传播，将有助于确定最容易感染的地点，以便有针对性地进行控制。这项工作还提高了科学家和资源管理者预测地理范围边界移动的能力，以应对全球变暖可能导致的气候变化。

In this project, mathematical modeling and genetic analysis are combined with experiments and field surveys to better predict the spread of the invasive hemlock woolly adelgid, Adelges tsugae (HWA), across the eastern United States. This forest pest kills eastern hemlock trees and has caused both economic and ecological damage. Genetic markers will be used to identify distinct HWA clonal lines that will each have its spread rate, population growth rate, and cold tolerance measured. This information will be used in combination with survey data reporting the genetic structure of the invasive populations to develop a mathematical model examining the role of dispersal and selection for surviving cold winter conditions in driving the range expansion of HWA.This research will substantially increase the understanding of how invasive species spread across landscapes. Hemlocks have both economic and cultural importance, and their loss concerns groups ranging from forestry officials to local citizens. Understanding how and why HWA spreads throughout the landscape will allow the identification of locations most at risk for infestation for targeted control efforts. This work also increases the ability of scientists and resource managers to anticipate the movement of geographic range boundaries in response to the changing climatic regimes likely to occur as a consequence of global warming.