Table 1.

Quantitative summary of the response of trout and charr populations to a 3 and 7°C increases in their thermal environment (see text for details). Statistical analysis used a one-way ANOVA for three different thermal regimes with 222 d.f. in the error term. The reported magnitude of the effect was determined by calculating effect size (Cohen 1988)—the difference in the estimated means divided by a pooled estimate of the standard error. Positive values for effect size indicate increasing population size; negative values indicate a decreasing population size.

	trout	ferox trout	charr	piscivorous charr
F	4.45	71.76	26.71	18.07
p	0.013	9.15 × 10−25	4.02 × 10−11	5.37 × 10−8
effect size 0–3°C increase	−0.30	−0.96	0.82	−0.47
effect size 0–7°C increase	−0.45	−1.95	1.28	−1.06