RAPID: Contrasting Ecological Gradients Before and After Dam Removal

19世纪，在五大湖地区建造了数千座小型水坝。这些水坝上下游的生态群落变得很不一样。出于对公共安全的考虑，现在需要拆除许多水坝，并开辟一条可以改变生态相互作用的移民走廊。 该项目的重点是最近在威斯康星州布里格斯维尔附近的大泉溪大坝和水库拆除。 上游社区包含了一个典型的冷水鱼组合为主的溪鳟鱼，刺鱼，杜父鱼和溪chubs。 大坝以下的河段主要是典型的温水组合--大嘴鲈鱼、蓝鳃鱼、黄鲈鱼和白色吸盘。 监测水温，鱼类群落结构和食物网结构的季节性变化将测试两个问题提出的替代结果：1。 寒冷的海水会取代温暖的海水中的鱼类， 向下游扩展的水组合？2. 大坝的拆除是否会让大型捕食者（鲈鱼）和竞争对手（吸盘）入侵上游，从而减少和取代冷水鱼群落？威斯康星州计划在本十年内拆除400多座小水坝。 公众对结果的兴趣总是很高的。 研究结果将对类似大坝拆除后的生态变化提供指导和展望。 这个项目将提供支持，以研究生加上四个本科小时工。 它也将作为一个示范网站的鱼类类（48名学生）在威斯康星大学麦迪逊分校的生态。

Thousands of small mill dams were constructed in the Great Lakes region during the 1800's. The ecological communities above and below these dams become quite different. Public safety concerns now require removal of many dams and open a migration corridor that can change ecological interactions. This project focuses on a recent dam and reservoir removal in Big Spring Creek near Briggsville, Wisconsin. The upstream community contains a typical cold water fish assemblage dominated by brook trout, sticklebacks, sculpins and creek chubs. The reach below the dam is dominated by a typical warm water assemblage--largemouth bass, bluegill, yellow perch and white suckers. Monitoring seasonal changes in water temperature, fish community structure and food web structure will test the alternative outcomes posed in two questions:1. Will the colder water displace the warm water fishes and allow the cold water assemblage to expand downstream?2. Will the dam removal allow upstream invasion by large predators (bass) and competitors (suckers) that can reduce and displace the coldwater fish community?More that 400 small dams are scheduled for removal in Wisconsin during the current decade. Public interest in outcomes is always high. Results of this study will offer guidance and expectation of the ecological changes that result from similar dam removals. This project will provide support to a graduate student plus four undergraduate hourly employees. It will also serve as a demonstration site for the Ecology of Fishes class (48 students) at UW-Madison.