Project Description

Adult salmon and steelhead migrating to their natal streams in tributaries of the Columbia River pass up to nine dams and their reservoirs, four each in the lower Columbia and Snake rivers and five in the mid Columbia River (see maps). Many of these fish are from stocks that are currently listed under the Endangered Species Act as a result of significant declines in their numbers over the last 100 years. Conservation efforts to recover Columbia River salmon stocks have focused on all life stages where potential improvements may be realized. Salmon and steelhead that migrated to the oceans as smolts and have successfully survived to feed, grow, and mature to adulthood in the ocean and then re-enter the Columbia River still face a potentially arduous journey to reach natal spawning streams. In this project, we use radiotelemetry to monitor and evaluate potential hazards for adult salmon and steelhead migrating through the Columbia River basin. Our main goal is to accurately characterize the migration behavior for these fish, identify potential problem areas in their passage, especially at dams and through reservoirs of the lower Columbia and Snake rivers, and evaluate methods to improve their migration and survival.

Fish used for these studies are primarily collected at Bonneville Dam, the first hydropower project most fish reach during their migration, about 235 km from the mouth of the Columbia River. They are then outfitted with radiotransmitters and transported about 10 km downstream from the dam for release. As these radio-tagged salmon and steelhead migrate upstream, they are monitored using a network of fixed-site radio receivers at dams, near the mouths of tributary rivers, and by mobile tracking by boat and truck. Additional information is gathered from tags returned from hatcheries, crews conducting spawning ground surveys, and from commercial and sport fisheries. Data accessible through this web site have been interpreted by project biologists, both for ease of use and because of the complexity of the receiver array and the database itself. Data have been summarized by placing codes on individual records, each code indicating a particular action (see Data Summary).

This project has been on-going since 1996. To date, we have tagged spring, summer, and fall chinook salmon and steelhead during multiple years and sockeye salmon during one year. We also have a companion project to evaluate the passage of Pacific lamprey in the lower Columbia River. Studies described here are primarily funded by the U. S. Army Corps of Engineers with assistance from the U. S. Geological Survey, Nation Marine Fisheries Service, Bonneville Power Administration, Bureau of Reclamation, and College of Natural Resources at the University of Idaho.

Project Personnel 1996-2004