Table 2. Sexual variation in whisker δ¹³C and δ¹⁵N values at each age-class.

Age-class	Male (‰)	Female (‰)	AIC		ωAIC
			~1	~Sex	~1	~Sex
δ13C
Age 0	−22.2 ± 1.3	−21.0 ± 0.8	151.3	147.6	0.14	0.86
Age 1	−21.3 ± 1.5	−19.8 ± 0.9	259.6	254.5	0.07	0.93
Age 2	−21.2 ± 1.3	−19.6 ± 0.9	193.6	187.2	0.04	0.96
Age 3	−20.9 ± 1.0	−19.2 ± 0.7	227.3	215.5	0.01	0.99
Age 4	−21.7 ± 0.8	−18.8 ± 0.4	190.5	163.7	0.01	0.99
Adult	−21.2 ± 1.5	−18.9 ± 0.4	308.0	299.1	0.01	0.99
δ15N
Age 0	9.0 ± 0.9	10.2 ± 0.4	78.8	71.6	0.03	0.97
Age 1	9.6 ± 0.8	10.3 ± 0.4	198.5	195.6	0.19	0.81
Age 2	10.1 ± 0.7	10.2 ± 0.4	174.5	176.4	0.73	0.27
Age 3	10.6 ± 0.6	10.4 ± 0.4	203.6	204.5	0.61	0.39
Age 4	10.2 ± 0.7	10.5 ± 0.3	238.4	238.6	0.53	0.47
Adult	11.0 ± 1.1	10.6 ± 0.4	299.8	300.5	0.58	0.42

The effect of sex on δ¹³C and δ¹⁵N values was tested for each age-class using mixed effect models to account for the repeated measurements for each individual (random effect) and the time-correlation of the data (auto-correlation coefficient). The most parsimonious models have been chosen according to their relative Akaike weight and are indicated in bold.