Climatic drivers and ecological impacts of a rapid range expansion by non-native smallmouth bass

Smallmouth bass (Micropterus dolomieu) are a globally introduced fish species that have experienced widespread range expansions in recent decades and which can have deleterious effects on native fish communities. Rapidly assessing their expansions will aid conservation and management actions geared towards controlling their spread and mitigating their impacts. Smallmouth bass have recently experienced a rapid upstream expansion in a Great Plains river (Laramie River, Wyoming, USA), which provided an opportunity to evaluate the drivers and impacts of this expansion by using a modified before-after, control-impact (BACI) design. Our objectives were to test whether climatic drivers (temperature, precipitation, flow) were related to this range expansion and subsequent effects of the expansion on native fish communities. Smallmouth bass population size in Grayrocks Reservoir increased following a climatically extreme wet year, with statistically extreme amounts of spring-time and June precip...小口黑鲈（Micropterus dolomieu）是一种全球引种的鱼类，近数十年来其分布范围已广泛扩张，且可对本土鱼类群落产生有害影响。快速评估其扩张动态，将有助于制定旨在管控其扩散、缓解其危害的保护与管理措施。近期，小口黑鲈在美国怀俄明州拉勒米河（北美大平原境内的一条河流）中出现了快速的上游扩张事件，这为我们采用改进型前后对照-控制影响（before-after, control-impact, BACI）实验设计评估该扩张的驱动因素与影响提供了契机。本研究的目标为检验气候驱动因子（水温、降水量、径流量）是否与该分布扩张事件，以及扩张后对本土鱼类群落产生的后续效应存在相关性。格雷罗克水库（Grayrocks Reservoir）的小口黑鲈种群数量在经历极端多雨年份后出现增长，春季及6月降水量达到统计学意义上的极端水平……