Sockeye Fry Entering Lake Washington from the Cedar River


Natural production of sockeye fry from the Cedar River is highly variable due to the high variability of the number of sockeye spawning in the river, predation, and variable natural conditions. The extremely low natural production of sockeye fry in 1996 was due to low returns and low survival cause by high flows. In the Cedar River flows above 2,000 cubic feet per second (cfs) have been identified to result in scour (movement of the river bed), which results in the loss of salmon eggs. Natural production has ranged from 0.7 million fry (1996) to 38.7 million fry (2001). Hatchery production has also been highly variable. This is due to highly variable numbers of adult sockeye returning to the Cedar River, and difficulties in collecting adult sockeye for the hatchery. The current hatchery production goal is 34 million fry. Hatchery production is also limited by a goal to limit hatchery influences.


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