Assessing Potential Freshwater Habitat Productivity for Anadromous Salmonids in the Columbia River Basin

Restoration of salmon habitat in the Columbia River basin over the last several decades is one the most costly restoration activities in history, yet our understanding of the results of these actions is limited. In an effort to understand where habitat restoration may be most effective, we have evaluated different scenarios of potential juvenile abundance for spring Chinook in both historically accessible and extant habitats throughout the Columbia River basin. Our analysis sums the maximum expected potential salmon abundance in small (<8 m bankfull width) and large tributaries throughout the system using two models predicting habitat type in each stream size. Estimated small stream habitats are pools and riffles; while larger stream habitats are separated into main channel, side channel, and off channel areas. Habitat specific midsummer juvenile salmon abundance data collected throughout the basin provide an estimate of the maximum expected fish density for each habitat type. This analysis provides an estimate of maximum potential salmon production that can be incorporated into life cycle modeling and recovery planning efforts throughout the basin.