Were there once annual salmon runs of 30 million fish in the Columbia River Basin?
Response: A two-year review of historic salmon numbers by the Northwest Power and Conservation Council examined all estimates on record and concluded that run sizes ranged from 10 to 16 million fish prior to development. This figure is widely accepted and cited in the literature as the most accurate figure. However, the analysis notes that run sizes have always fluctuated widely, depending on river and ocean conditions. One method for calculating historic run sizes was the calculation of an estimated run size based on the assumption that fish wheels caught a certain percentage of the run. Using this method, one early estimate came up with a figure of about 35 million fish. The Council’s analysis found that the figure was not credible because assumptions of the number of fish caught in fish wheels was unrealistic.
