2006-2009 Multi-year Summary Report for Bonneville Power Administration

The findings of the BPA project from 2006 to 2009 have been compared and summarized.  Highlights include: 

  1. Repeatedly over the entire study, no difference in delayed mortality was found between hatchery-origin spring Chinook from the Snake River (8 dams to transit) and the Yakima River (4 dams).
  2. Barged and freely migrating Chinook revealed no evidence of differential-delayed mortality; this does not support the hypothesis that stress from transportation results in a reduction in survival.
  3. Survival rates in freshwater and coastal ocean are equivalent. Read the report here.