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A manipulative thermal challenge protocol for adult salmonids in remote field settings

Daniel S. Donnelly·Vanessa R. von Biela·Stephen D. McCormick·Sarah M. Laske·Michael P. Carey·Shannon C. Waters-Dynes·Lizabeth Bowen·Randy J Brown·Sean Larson·Christian E. Zimmerman
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Abstract

Manipulative experiments provide stronger evidence for identifying cause-and-effect relationships than correlative studies, but protocols for implementing temperature manipulations are lacking for large species in remote settings. We developed an experimental protocol for holding adult Chinook salmon ( Oncorhynchus tshawytscha ) and exposing them to elevated temperature treatments. The goal of the experimental protocol was to validate heat stress biomarkers by increasing river water temperature from ambient (~14°C) to a treatment temperature of 18°C or 21°C and then maintain the treatment temperature over 4 hours within a range of ±1.0°C. Our protocol resulted in a mean rate of temperature rise of 3.71°C h-1 (SD = 1.31) to treatment temperatures and mean holding temperatures of 18.0°C (SD = 0.2) and 21.0°C (SD = 0.2) in the low- and high-heat treatments, respectively. Our work demonstrated that manipulative experiments with large, mobile study species can be successfully developed in remote locations to examine thermal stress.

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Daniel S. Donnelly, Vanessa R. von Biela, Stephen D. McCormick, Sarah M. Laske, Michael P. Carey, Shannon C. Waters-Dynes, Lizabeth Bowen, Randy J Brown, Sean Larson, Christian E. Zimmerman. 2020-09-14. A manipulative thermal challenge protocol for adult salmonids in remote field settings. https://doi.org/10.1093/conphys%2Fcoaa074

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