Table 2.

Test statistics from linear mixed effects models testing for differences in δ¹³C and δ¹⁵N among species within habitats.

Habitat/isotope	Likelihood ratio test statistics			Marginal R2	Conditional R2
	F	df	P
River upstream
δ13C	2.09	4, 58.8	0.094	0.09	0.41
δ15N	33.93	4, 50.8	< 0.001	0.69	0.79
River downstream
δ13C	5.81	5, 96.12	< 0.001	0.16	0.44
δ15N	9.77	5, 96.39	< 0.001	0.31	0.41
Reservoir
δ13C	50.13	4, 135.26	< 0.001	0.54	0.61
δ15N	15.54	4, 122.04	< 0.001	0.26	0.28

Mixed effects models included a random effect of month.