Table 1. Mean isotope ratios and generalized isotope endpoints, corrected for trophic fractionation, that we used to calculate diet proportions for grizzly bears.
Data for salmon and plants for δ13C and δ15N are taken from Mowat and Heard (2006); endpoints for δ34S and generalized meat are derived from data from this study.
| Food class | δ13C | Δδ13C | SD | δ15N | Δδ15N | SD | n1 | δ34S | Δδ34S | SD | n |
|---|---|---|---|---|---|---|---|---|---|---|---|
| North Coast generalized meat | -24.8 | -22.8 | 1 | 2.5 | 6.5 | 1 | 107 | 0.6 | 1.6 | 4.52 | 31 |
| Generalized anadromous salmon | -19.9 | -18.9 | 1 | 12.5 | 15.2 | 1 | 338 | 19.1 | 15.3 | 0.5 | 21 |
| Generalized plant baseline | -26.6 | -24.6 | 2 | -2.8 | 2.8 | 3 | 200 | -2.03 | -0.4 | 4.2 | 44 |
1This sample size applies to both carbon and nitrogen.
2This is the mean of the SD for moose, goat and marmot.
3This is the mean for all bear samples where δ15N < 3.7.