Sub‐lethal temperature thresholds indicate acclimation and physiological limits in brook trout Salvelinus fontinalis

• DOI: 10.1111/jfb.14411
• Publication Date: 2020-05-24T06:44:40Z
• Authors: Scott M. Morrison; Theresa E. Mackey; Travis Durhack; Jennifer D. Jeffrey; Lilian M. Wiens; Neil J. Mochnacz; Caleb T. Hasler; Eva C. Enders; Jason R. Treberg; Ken M. Jeffries
• Keywords: Fontinalis

Abstract The upper thermal tolerance of brook trout Salvelinus fontinalis was estimated using critical maxima (CT max ) experiments on fish acclimated to temperatures that span the species' range (5–25°C). CT increased with acclimation temperature but plateaued in 20, 23 and 25°C. Plasma lactate highest, hepato‐somatic index ( I H lowest at 25°C, which suggests additional metabolic costs those temperatures. results suggest there is a sub‐lethal threshold between 20 23°C, beyond experience reduced physiological performance.