Fish Passage Monitoring- Build It and They Will Come: Measuring Success of Fish Passage Enhancements

Hydroelectric dams, irrigation diversions, flood control structures and altered habitats have contributed to ongoing issues associated with both upstream and downstream fish passage.  Past practices and developments were implemented without much regard for fish passage, connectivity, habitat alterations and efects on a larger ecosystem scale. Through development and implementation of state and federal laws protecting aquatic species and their habitats, fish passage is being restored, improved and enhanced at facilities all over the world for a variety of species.  Fish passage can be an essential element of a species life history or can provide advantages to certain life stages and species of aquatic organisms.  When passage is interrupted or lost, fish can be forced into less favorable habitats or denied the opportunity to reproduce at all. Understanding fish population needs, and fish species behavior are the basis for designing and implementing successful fish passage enhancements; but merely building a facility or fixing a project does not prove its effectiveness. Fish passage monitoring has taken many forms and is conducted sometimes to see what has worked, and how well it has worked.  A measure of success for fish passage is somewhat project and species specific to any given ecosystem and this session of AFS will examine past fish passage monitoring efforts and their results in meeting goals or objectives of passage.  Fish passage monitoring uses many tools from electronic tagging systems, mark-recapture studies and video monitoring systems that will be discussed in this symposium.  This symposium will expose the audience to extensive and intricate large-scale fish passage facilities that were built and tested, some with predetermined passage and survival criteria.