What percentage of salmon that cross Lower granite survive to Idaho hatcheries? Not counting harvested fish. Just a % number that will survive the journey


Natural mortality (excluding harvest) for salmon between Lower Granite Dam and hatchery facilites varies by facility and year but typically is not more than 5%. So if  there were no harvest in Idaho and 10,000 hatchery fish crossed Lower Granite Dam 9,500 or more would make it back to hatcheries. Some portion of the 5% that do not make it back to hatcheries die or are eaten by predators during their upstream migration and others stray into other streams and spawn naturally.

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Friday, July 6, 2012 - 9:47 AM MDT