• Research helps continually improve safe passage for fish through the dams

    Jan 28, 2016: At least 17 intensively monitored watersheds in the Northwest are beginning to provide detailed scientific insight into how investments in river and stream restoration can most effectively boost fish populations, according to a paper published this month in Fisheries, the monthly journal of the American Fisheries Society.

    “This is the best method we have for understanding if restoration improves watershed scale productivity, how well it works, and how we can get better at it,” said Stephen Bennett, a research scientist at Utah State University and lead author of the paper that also includes authors from NOAA Fisheries and state fisheries agencies in California, Washington, Oregon, and Idaho.

    Northwest salmon and steelhead have long suffered from habitat loss and degradation, and restoring that habitat is a key strategy for rebuilding their populations. Climate, ocean conditions, natural variability and other factors also influence their abundance, however, making it difficult to identify and quantify the specific contributions of habitat restoration.

    Rivers and streams in IMWs are heavily outfitted with systems to track salmonids from fry to adults. Antennas buried in stream bottoms in some areas detect tiny electronic chips in fish each time they pass by, documenting how many use the restored habitat.

    With this rich data set, scientists can discern the benefits of restoration by comparing the numbers to separate “control” streams without restoration. In areas of Asotin Creek in Washington, for instance, scientists have documented a 250 percent increase in numbers of juvenile fish with restored habitat compared to those without.

    The new paper identifies the essential elements of intensively monitored watersheds, describes the challenges involved, and reports preliminary results from those already underway.
    For more information on IMWs and snapshots of results from individual IMWs, visit


    A creek in the Lemhi Subbasin, one of the Intensively Monitored Watersheds, where water transactions have added water for fish habitat.

  • Peer-reviewed research, funded by BPA, advances knowledge of fish protection

    Program based on best available science

    BPA, with funding from its electric utility customers, supports hundreds of projects to improve fish habitat, fish passage and fish health. All of the projects include some research or monitoring component to ensure they are achieving their intended biological objectives. BPA and its partners use the research findings to ensure programs are based on the best available science and to continually improve results for fish.Many of these researchers have published their findings in scholarly journals. Click on the link below to access a list of and links to some of the recent (since 2010) studies published in peer-reviewed journals that were funded in part or all by BPA. This research is helping to advance the state of the science of fish health and fish ecology.

    Peer Reviewed Research

    Recent journal articles on Columbia Basin fish  

    The Influence of Size at Release on Performance of Imnaha River Chinook Salmon Hatchery Smolts; Joseph Feldaus et al, North American Journal of Fisheries Management, March 2016

    Predation by Northern Pikeminnow and Tiger Muskellunge on Juvenile Salmonids in a High-Head Reservoir: Implications for Anadromous Fish Reintroductions; Mark Sorel et al, Transactions of the American Fisheries Society, April 2016

    Evaluation of Back-Calculated Size and Timing Estimates for Juvenile Chinook Salmon Using Otolith Structure and Chemistry; Andrew Claiborne et al, Transactions of the American Fisheries Society, April 2016