W. Nicholas Beer
Columbia Basin Research
School of Aquatic and Fishery Sciences
University of Washington
Box 358218
Seattle, Washington 98195
Prepared for:
U.S. Department of Energy
Bonneville Power Administration
Environment, Fish and Wildlife
P.O. Box 3621
Portland, OR 97283-3621
March 2009
Abstract
Preseason predictions of run size and migration timing are modified by inseason conditions and passage observations to monitor the run size and migration timing of spring Chinook salmon (Oncorhynchus tshawytscha) at Bonneville Dam on the Columbia River. As the season progresses, patterns in the arrival of the fish dictate modification of the size and timing parameters. The preseason prediction is based on a model that uses environmental conditions and genetics. The latest data within a year is then used in up to five different ways to update that preseason prediction.