Table S1. Test statistics (with * indicating a significant difference at an alpha level of 0.05) of differences among carbon (δ13C)andnitrogen (δ15N) isotope values among prey species (excluding vegetation) sampled in the traditional territory of the Taku River Tlingit First Nation in northwestern British Columbia, Canada, 2009-2010. Three statistical tests are reported: 1) Welch’s two sided t-test (t), 2) two-sided Wilcoxon rank sum test with continuity correction (W), and 3) multiple analysis of variance (F).

Nitrogen / Carbon / Manova
Species 1 / Species 2 / t / W / t / W / F
Caribou / Moose / 5.51 / * / 276 / * / 14.43 / * / 299 / * / 126.84 / *
Caribou / Beaver / 0.83 / 58 / 1.60 / 69 / 5.58 / *
Caribou / Mtn goat / 3.41 / * / 118 / * / 6.20 / * / 136 / * / 24.19 / *
Caribou / Stone's sheep / 1.36 / 79 / -0.05 / 56 / 0.36
Caribou / Least chipmunk / 0.42 / 58 / 3.07 / * / 82 / * / 10.20 / *
Caribou / Showshoe hare / 7.62 / * / 249 / * / 18.78 / * / 253 / * / 260.63 / *
Caribou / Vole / -6.06 / * / 3 / * / 2.17 / 91 / * / 25.48 / *
Moose / Beaver / -1.21 / 16 / -1.77 / 8 / * / 7.44 / *
Moose / Mtn goat / -4.00 / * / 9 / * / -3.34 / * / 7 / * / 17.20 / *
Moose / Stone's sheep / -4.01 / * / 4 / * / -9.37 / * / 0 / * / 62.58 / *
Moose / Least chipmunk / -1.79 / 9 / -2.28 / 4 / * / 6.77 / *
Moose / Showshoe hare / 3.20 / * / 115 / * / 6.65 / * / 143 / * / 52.92 / *
Moose / Vole / -9.26 / * / 0 / * / -3.94 / * / 0 / * / 71.64 / *
Beaver / Mtn goat / 0.23 / 12 / 0.53 / 14 / 0.24
Beaver / Stone's sheep / -0.27 / 8 / -1.56 / 5 / 1.32
Beaver / Least chipmunk / -0.34 / 6 / 0.28 / 9.5 / 0.10
Beaver / Snowshoe hare / 2.40 / 38 / * / 3.78 / * / 44 / * / 25.97 / *
Beaver / Vole / -4.42 / * / 0 / * / -0.37 / 8 / 9.15 / *
Mtn goat / Stone's sheep / -1.61 / 7 / -4.89 / * / 1 / * / 10.52 / *
Mtn goat / Least chipmunk / -0.74 / 8 / -0.33 / 11 / 0.41
Mtn goat / Snowshoe hare / 6.75 / * / 66 / * / 8.17 / * / 66 / * / 75.95 / *
Mtn goat / Vole / -8.19 / * / 0 / * / -1.58 / 8 / 46.65 / *
Stone's sheep / Least chipmunk / -0.18 / 9 / 2.84 / * / 18 / 11.53 / *
Stone's sheep / Snowshoe hare / 6.34 / * / 55 / * / 13.65 / * / 55 / * / 123.76 / *
Stone's sheep / Vole / -6.86 / * / 0 / * / 1.96 / 21 / 72.33 / *
Least chipmunk / Snowshoe hare / 3.06 / * / 41 / * / 5.36 / * / 44 / * / 24.99 / *
Least chipmunk / Vole / -4.27 / * / 0 / * / -0.92 / 5 / 18.59 / *
Snowshoe hare / Vole / -10.54 / * / 0 / * / -7.33 / * / 0 / * / 94.78 / *

Table S2. Means and SD of carbon and nitrogen isotopes from all species sampled in the traditional territory of the Taku River Tlingit First Nation in northwestern British Columbia, Canada, 2009-2010.

Trophic level / Species / n / C / C SD / N / N SD
Predator / Black bear middle / 10 / -23.5 / 0.8 / 5.3 / 0.3
Predator / Black bear root / 9 / -23.8 / 0.5 / 4.4 / 0.5
Predator / Black bear tip / 11 / -23.6 / 0.6 / 5.5 / 0.5
Predator / Grey wolf middle / 12 / -22.2 / 0.6 / 6.2 / 0.4
Predator / Grey wolf root / 11 / -22.4 / 0.5 / 6.1 / 0.3
Predator / Grey wolf tip / 12 / -22.2 / 0.5 / 6.3 / 0.4
Predator / Grizzly bear middle / 14 / -23.4 / 0.9 / 5.6 / 0.9
Predator / Grizzly bear root / 14 / -23.4 / 0.8 / 5.4 / 0.8
Predator / Grizzly bear tip / 16 / -23.5 / 0.7 / 5.4 / 0.7
Prey / Beaver / 4 / -24.3 / 1.2 / 2.8 / 1.3
Prey / Caribou / 23 / -23.4 / 0.4 / 3.4 / 0.9
Prey / Least Chipmunk / 4 / -24.5 / 0.7 / 3.1 / 1.2
Prey / Moose / 13 / -25.4 / 0.4 / 2.0 / 0.5
Prey / Mountain goat / 6 / -24.7 / 0.5 / 2.7 / 0.2
Prey / Snowshoe hare / 11 / -26.7 / 0.5 / 1.2 / 0.7
Prey / Stone's sheep / 5 / -23.3 / 0.4 / 3.0 / 0.4
Prey / Vole / 5 / -24.1 / 0.7 / 6.3 / 1.0
Vegetation / Arrow-leaved balsamroot / 4 / -27.5 / 0.8 / 1.9 / 1.6
Vegetation / Blueberry / 4 / -28.3 / 1.1 / 0.9 / 1.1
Vegetation / Clover / 4 / -27.6 / 1.5 / -1.5 / 0.7
Vegetation / Cow parsnip / 4 / -27.1 / 0.3 / -0.7 / 1.1
Vegetation / Crowberry / 4 / -26.1 / 0.3 / -1.3 / 0.8
Vegetation / Dandelion / 4 / -29.9 / 0.9 / -0.2 / 2.6
Vegetation / Fescue spp. / 4 / -26.9 / 0.9 / -1.8 / 1.4
Vegetation / Horsetail / 4 / -28.1 / 1.1 / 2.4 / 1.5
Vegetation / Kinnickinnick / 4 / -27.0 / 1.1 / -2.3 / 1.2
Vegetation / Lupine spp. / 4 / -27.4 / 2.8 / -1.0 / 1.1
Vegetation / Rose / 4 / -25.1 / 1.8 / 1.9 / 2.6
Vegetation / Sedges / 4 / -27.8 / 1.1 / 2.5 / 0.9
Vegetation / Soapberry / 4 / -26.6 / 1.2 / -0.3 / 1.1

Figure S1. Results of the replicate analysis. Relationship between selected mammalian guard hair samples and their replicate values of carbon (δ13C; a)andnitrogen (δ15N; b) isotope values collected non-invasively from grey wolves (Canis lupus), black bears (Ursusamericanus), grizzly bears (U. arctos) and their prey in the traditional territory of the Taku River Tlingit First Nation in northwestern British Columbia, Canada, 2009-2010.

Figure S2. Mean (with SD bars in black) prey carbon (δ13C)andnitrogen (δ15N) isotope values from tissue samples (guard hair for mammals and above ground tissue for plants), and observed predator isotope values for middle summer corrected for fractionation (with black circles) from the traditional territory of the Taku River Tlingit First Nation in northwestern British Columbia, Canada, 2009-2010.