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Critical thermal maxima of coho salmon ( Oncorhynchus kisutch ) fry under field and laboratory acclimation regimes

John T. Konecki·Carol Ann Woody·Thomas P. Quinn
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Abstract

Juvenile coho salmon ( Oncorhynchus kisutch ) from three populations in Washington State were captured in the field and tested for critical thermal maximum (CTM). Tolerances varied among the populations (mean CTMs were 28.21, 29.13, and 29.23 °C) and exceeded published data from some laboratory tests. The population from a relatively cool stream had a lower CTM than the two populations from warmer streams. However, after the salmon had been in the laboratory for 3 months under constant, common temperature regimes, the CTMs no longer differed, indicating that the population-specific differences resulted from different acclimation regimes rather than from genetic adaptation.

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John T. Konecki, Carol Ann Woody, Thomas P. Quinn. 1995. Critical thermal maxima of coho salmon ( Oncorhynchus kisutch ) fry under field and laboratory acclimation regimes. https://doi.org/10.1139/z95-117

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