Fishery managers have had difficulty estimating the Columbia sockeye run and this year predicted the count at Bonneville Dam would be 125,000 fish. But 30,374 sockeye passed through on 23 June, the most in a single day since the dam was built in 1938. Two days later the estimate for the year doubled, to 250,000 sockeye. On Saturday, the run exceeded this estimate and reached 329,579 fish. Before dams were built on the Columbia and Snake rivers, sockeye run estimates reached 3 million fish. The run almost died after the dams came in and then, with much help, have now started a comeback.
The size of this summer's run is causing a stir up and down the river. Native Americans are selling more fish earlier, and the run is open to sport fishermen from the mouth of the Columbia to the Oregon/Washington border.
Experts point to many reasons for increasing runs, among them improvements to dams and hatchery practices, better tributary habitat and increased smolt releases. But the primary reasons, scientists say, are Court-ordered increased spills from dams in the spring, when smolts migrate downstream, and improved conditions in the ocean where salmon spend two to four years growing up.
source: Fishlink Sublegals