Appendix Table S1. Results of the glmm model of the effects of predator drivers. This includes the dispersion parameters of the model, the variance of the random intercepts and the estimates, z-values, and p-values of mustelid abundance (tracks/100km). Dispersion Parameters Random Effects Year Grid Fixed Effects (Intercept) MustelidAbundance Pearson’s ChiSquare 1917 Variance 0.30 0.11 Estimate -1.81 1.28 ratio 0.82 Std. Dev. 0.55 0.33 Std. Error 0.19 0.28 df 2332 p 1 z value -9.6 4.5 P 0 6.19E-06 Table S2. Results of the glmm model of the effects of energetic drivers. This includes the dispersion parameters of the model, the variance of the random intercepts and the estimates, z-values, and p-values of the 3-day coldest temperatures during lactation (ColdestTa), previous year’s cone index (ConeIndex), litter size, whether the individuals were food supplemented (FoodSup), and the interactions between resources (ConeIndex and FoodSup) and litter size or coldestTa. Dispersion Parameters Random Effects Year Grid Fixed Effects (Intercept) ColdestTa ConeIndex LitterSize FoodSup ColdestTa:ConeIndex ConeIndex:LitterSize ColdestTa:FoodSup LiterSize:FoodSup Pearson’s ChiSquare 1899 Variance 0.68 0.08 Estimate -1.92 -1.79 -0.67 0.38 -0.09 -0.15 -0.39 3.00 -0.59 ratio 0.82 Std. Dev. 0.82 0.28 Std. Error 0.23 0.94 0.30 0.14 0.23 1.53 0.25 1.63 0.26 df 2325 p 1 z value -8.5 -1.9 -2.2 2.7 -0.4 -0.1 -1.6 1.8 -2.3 P 0 0.05 0.03 0.008 0.69 0.92 0.11 0.07 0.03 Table S3. Results of the glmm model of the effects of fitness drivers. This includes the dispersion parameters of the model, the variance of the random intercepts and the estimates, z-values, and p-values of juvenile overwinter survival, and maternal age. Dispersion Parameters Pearson’s Chi- Ratio df p Square Random Effects Year Grid Fixed Effects (Intercept) OverwinterSurvival MaternalAge 1910 Variance 0.56 0.10 Estimate -2.01 1.14 0.33 0.82 Std. Dev. 0.75 0.33 Std. Error 0.22 0.36 0.12 2332 1 z value -9.3 3.1 2.8 p 0 0.002 0.004 Table S4. Results of the glmm model of the effects of relative energetic and fitness drivers. This includes the dispersion parameters of the model, the variance of the random intercepts and the estimates, z-values, and p-values of the 3-day coldest temperatures during lactation (ColdestTa), previous year’s cone index (ConeIndex), litter size, maternal age, juvenile overwinter survival, mustelid abundance, and whether the individuals were food supplemented (FoodSup), and the interactions between energetics (ConeIndex or FoodSup, and litter size or coldestTa) and fitness (overwinter survival). Dispersion Parameters Random Effects Year Grid Fixed Effects (Intercept) ColdestTa ConeIndex OverwinterSurvival LitterSize FoodSup MustelidAbundance MaternalAge ColdestTa:ConeIndex ColdestTa:OverwinterSurvival ConeIndex:OverwinterSurvival ConeIndex:LitterSize OverwinterSurvival:LitterSize OverwinterSurival:FoodSup LitterSize:FoodSup ColdestTa:ConeIndex:OverwinterSurvival ConeIndex:OverwinterSurvival:LitterSize OverwinterSurival:LitterSize:FoodSup Pearson’s Chi-Square 1891 Variance 0.11 0.07 Estimate -1.68 -0.07 -0.34 0.30 0.44 -0.24 1.06 0.27 -0.03 0.07 1.38 -0.38 0.14 0.53 -0.86 -0.29 0.75 0.76 ratio 0.82 Std. Dev. 0.34 0.26 Std. Error 0.17 0.03 024 0.27 0.16 0.23 0.22 0.12 0.05 0.06 0.56 0.27 0.35 0.38 0.29 0.15 0.81 0.57 df 2316 p 1 z value -10.1 -2.4 -1.4 1.1 2.7 -1.0 4.6 2.2 -0.6 1.2 2.5 -1.4 0.4 1.4 -3.0 -2.0 0.9 1.3 P 0 0.01 0.16 0.26 0.007 0.30 <0.0001 0.03 0.56 0.23 0.01 0.16 0.69 0.17 0.003 0.04 0.35 0.18