"Overall, this study indicates that exposure to water temperatures up to 16.58C will not have deleterious effects on survival or growth from egg to emergence if temperatures decline at a rate of 0.28C/d or more after spawning. Although fall Chinook salmon survived low initial dissolved oxygen levels, the delay in emergence could have significant long-term effects on their survival. Thus, an exemption to the state water quality standards for temperature—but not oxygen—may be warranted for the portions of the Snake River where fall Chinook salmon spawn."
"Our results showed that the mortality of fall Chinook salmon embryos exposed to variable temperature and oxygen conditions was not affected by dissolved oxygen levels as low as 4 mg O2/L over a range of temperatures from 158C to 16.58C. Embryo mortality increased markedly at initial incubation temperatures of178C or more. There was a rapid decline in survival between 16.58C and 178C and no significant difference in survival at temperatures up to 16.58C. This upper thermal tolerance is similar to that reported in other studies that have used a declining thermal regime to evaluate survival in salmon embryos".
"Overall, this study indicates that exposure to water temperatures up to 16.58C will not have deleterious effects on survival or growth from egg to emergence if temperatures decline at a rate of 0.28C/d or more after spawning. Although fall Chinook salmon survived low initial dissolved oxygen levels, the delay in emergence could have significant long-term effects on their survival. Thus, an exemption to the state water quality standards for temperature—but not oxygen—may be warranted for the portions of the Snake River where fall Chinook salmon spawn."
"Our results showed that the mortality of fall Chinook salmon embryos exposed to variable temperature and oxygen conditions was not affected by dissolved oxygen levels as low as 4 mg O2/L over a range of temperatures from 158C to 16.58C. Embryo mortality increased markedly at initial incubation temperatures of178C or more. There was a rapid decline in survival between 16.58C and 178C and no significant difference in survival at temperatures up to 16.58C. This upper thermal tolerance is similar to that reported in other studies that have used a declining thermal regime to evaluate survival in salmon embryos".