CTMax of wild juvenile salmon exposed to diel cycles: (A) 16–21°C (control group); or multi-day thermal stress (closed symbols; 60–120 h) of (B) 18–27°C; (C) 20–27°C; (D) 22–27°C. Data are presented as mean ± SEM (n = 5–10). Open symbols (t = 24 h) represent pre-thermal stress sampling time points and were secondarily used to assess the effect of ‘trial’. Asterisks indicate significant differences among treatments (P < 0.05).