American shad Alosa sapidissima are non-native anadromous clupeids that have become extremely abundant in the Columbia River during the last 70 years, with adult counts at Bonneville Dam being as high as 5 million fish during recent years.  American shad adults, perhaps over 20 million, enter the lower Columbia River during April-June for spawning.  Juveniles outmigrate in vast numbers primarily during July through early winter, and evidence suggests that many overwinter in the estuary.  However, there is very little known about their potential positive or negative impacts on the aquatic community.  

The goal of this project is to provide credible lines of argument regarding whether shad provide positive benefits or are detrimental to efforts to restore Columbia River fisheries.  This project will provide information on the role that juvenile and adult shad play as competitors for forage, as forage themselves, and as potential vectors of disease that may influence the productivity of salmonid populations.  While little is known about American shad in the Columbia River, this project will build upon extensive research from the east coast of North America where efforts to restore American shad runs to rivers have been underway for decades.  

The project includes coordinated activities to address three objectives; 1) shad as potential competitors of juvenile salmon for forage, 2) the role that shad play as prey for juvenile salmon (a potential positive effect) and as prey supporting growth of native and introduced predators of juvenile salmon (a potential negative effect), and 3) the role that shad may play as vectors of disease that poses a potential threat to the restoration of salmonid populations.  Field, laboratory, and modeling tasks will begin in 2007 and will continue through 2009.  Field sampling activities will require fish collection permits from the states of Oregon and Washington, and sampling done at juvenile collection facilities at dams will require coordination and approval from the Army Corps of Engineers.  The project proponents will consult with NOAA Fisheries staff regarding the need for permitting under the Endangered Species Act.