Effect of egg concentration in an incubation channel on survival of chinook salmon fry

Eyed eggs of chinook salmon (Oncorhynchus tshawytscha) were planted in the Abernathy (Washington) incubation channel at concentrations of 7,180, 10,764, and 14,349 eggs/m² of gravel. Numbers of eggs planted were 200,000, 240,000, and 200,800, and survivals to the downstream migrant stage were 78.5, 85.0, and 79.1%, respectively; the differences were not statistically significant. The concentration of 14,349 eggs/m² is near the capacity of the channel. This stocking rate is 10 times that commonly recommended for artificial spawning channels. Egg concentration was apparently limited only by the physical capacity of the gravel.