Executive Summary
The Intensively Monitored Watershed (IMW) program has been funded by the Salmon Recover Funding Board (SRFB) since June 2003 to evaluate the efficacy of habitat restoration in increasing salmon production. The basic premise of the IMW program is that the complex relationships controlling salmon response to habitat conditions can best be understood by concentrating monitoring and research efforts at a few locations. Focusing efforts on a relatively few locations enables enough data on physical and biological attributes of a system to be collected to develop a comprehensive understanding of the factors affecting salmon production in freshwater. This report describes work completed in FY2006 and outlines restoration and research plans for FY 2007.
There are three sets of IMW sites (complexes) in western Washington focusing on coho salmon and steelhead trout and the Skagit River estuary focusing on ocean-type chinook (Figure 1). Planned restoration projects will be complete in the Strait of Juan de Fuca (SJF) complex by fall 2006. Mark-recapture studies using permanent PIT tag readers in the SJF indicate that a substantial proportion of the juvenile coho salmon migrate to salt water in the fall rather than the typical March-June spring migration. Fall migrants were significantly smaller when tagged suggesting that they have been competitively displaced from the available habitat.
Coho production in three of the Hood Canal streams reached record highs, 160, 182, and 693% of the long-term average, in Stavis, Seabeck, and Little Anderson Creek, while Big Beef production was slightly above the average. The extraordinary increase in production in Little Anderson Creek, also observed in preliminary data from 2006, coincides with a culvert replacement on Anderson Hill Road in 2003 which removed a partial barrier to upstream fish migration.
Efforts in the Lower Columbia complex continue to focus on extending and improving the database of pre-restoration data. Restoration is planned to begin in 2009. The Lower Columbia Fish Recovery Board and the Cowlitz County Conservation District will develop a restoration plan for these basins, based on the approved recovery plan. This will form the basis for implementing restoration projects.
We have worked with the Skagit River System Cooperative and the Northwest Fisheries Science Center to integrate and expand their existing monitoring to address questions specific to the effects of estuary restoration on juvenile chinook growth and survival.
A study plan detailing the entire IMW program was delivered to the Independent Science Panel in April, 2006. It is currently under review and will be revised as needed based on this review.