Table 1. Diet composition (mean ± SE %) of caribou in northwest Alaska derived from microhistology of feces collected in 2012 that were corrected for digestibility (sensu Gustine et al., 2011).
| A. All Samples | |||||||
|---|---|---|---|---|---|---|---|
| Class | N | Shrub | Forbs | Gram | Lichen | Misc | Moss |
| Pregnant Cows | 81 | 7.7 (0.6) | 2.9 (0.5) | 6.1 (0.4) | 70.1 (1.7) | 0.0 (0.0) | 13.2 (1.0) |
| Non-Pregnant Cows | 34 | 6.0 (0.9) | 2.3 (0.7) | 4.5 (0.7) | 75.8 (2.7) | 0.1 (0.0) | 11.4 (1.5) |
| Bulls | 92 | 7.0 (0.6) | 1.5 (0.5) | 5.0 (0.4) | 75.9 (1.6) | 0.2 (0.0) | 10.5 (0.9) |
| B. Arctic caribou | |||||||
| Class | N | Shrub | Forbs | Gram | Lichen | Misc | Moss |
| Pregnant Cows | 75 | 8.2 (0.6) | 3.1 (0.7) | 6.3 (0.4) | 68.4 (1.8) | 0.0 (0.0) | 14.0 (1.0) |
| Non-Pregnant Cows | 28 | 6.8 (1.0) | 2.6 (0.7) | 5.2 (0.5) | 72.5 (2.9) | 0.1 (0.0) | 13.0 (1.7) |
| Bulls | 74 | 7.6 (0.7) | 1.7 (0.3) | 5.9 (0.5) | 72.8 (1.7) | 0.1 (0.0) | 11.9 (1.0) |
| C. Galena Mountain Herd caribou | |||||||
| Class | N | Shrub | Forbs | Gram | Lichen | Misc | Moss |
| Pregnant Cows | 6 | 2.1 (0.9) | 0.8 (0.5) | 3.3 (1.7) | 90.5 (2.2) | 0.1 (0.1) | 3.1 (1.5) |
| Non-Pregnant Cows | 6 | 2.2 (0.7) | 1.1 (1.0) | 1.0 (0.5) | 91.5 (4.6) | 0.3 (0.2) | 3.9 (2.5) |
| Bulls | 18 | 4.2 (0.5) | 0.4 (0.1) | 1.6 (0.4) | 88.8 (1.4) | 0.4 (0.1) | 4.7 (1.0) |
‘Gram’ is graminoids, which includes grasses and sedges. ‘Forbs’ includes Equisetum spp. ‘Misc’ is miscellaneous which is comprised mostly of items difficult to digest such as seeds and spruce needles.