Table 2. Descriptive statistics for data used to build models to predict grizzly bear density in interior North America.
| Variable | Occupied areas | Unoccupied areas | ||||||||
|
SD | Min | Max | n |
|
SD | Min | Max | n | |
| Population size | 92 | 96 | 15 | 765 | 76 | 0 | 0 | 0 | 0 | 14 |
| Study area size (km2) | 5110 | 4297 | 789 | 22875 | 76 | 6358 | 1629 | 3913 | 8959 | 14 |
| Barren (% of study area) | 6.7 | 8.6 | 0.0 | 34.6 | 76 | 1.7 | 2.1 | 0.1 | 6.7 | 14 |
| Density (barren area removed) | 23.0 | 15.1 | 2.5 | 64.6 | 76 | 0.0 | 0.0 | 0.0 | 0.0 | 14 |
| CL relative (% of density) | 1.0 | 0.5 | 0.1 | 1.9 | 76 | 0.8 | 0.3 | 0.5 | 1.0 | 14 |
| Human-caused mortality (%) | 3.7 | 3.9 | 0.0 | 20.1 | 76 | 01 | 0.0 | 0 | 0 | 14 |
| Annual precipitation (cm) | 84 | 40 | 16 | 199 | 76 | 52 | 7 | 43 | 68 | 14 |
| NDVI | 116 | 15 | 77 | 137 | 76 | 129 | 5 | 115 | 136 | 14 |
| AET | 296 | 104 | 97 | 443 | 76 | 342 | 60 | 228 | 440 | 14 |
| Average annual temperature | −4.0 | 5.0 | −17 | 3.7 | 76 | 0.9 | 3.1 | −5.0 | 4.7 | 14 |
| Ruggedness | 3.9 | 1.4 | 1.0 | 6.0 | 76 | 2.2 | 1.3 | 1.0 | 4.2 | 14 |
| Trees (>25% per pixel) | 48.1 | 34.7 | 0.0 | 99.5 | 76 | 69.7 | 30.0 | 8.4 | 99.7 | 14 |
| Herb-shrub (>50% per pixel) | 57.6 | 28.1 | 3.1 | 99.1 | 76 | 50.6 | 28.4 | 6.8 | 94.0 | 14 |
| Salmon (% of diet) | 1.0 | 3.0 | 0.0 | 14.0 | 76 | 1.5 | 3.6 | 0.0 | 10.2 | 14 |
| Kokanee (% of diet) | 0.7 | 3.5 | 0.0 | 26.0 | 76 | 0.6 | 1.5 | 0.0 | 5.1 | 14 |
| Meat (% of diet) | 25.1 | 15.5 | 0.0 | 58.2 | 76 | 29.3 | 13.9 | 12.5 | 48.1 | 14 |
| Human density (humans/km2) | 0.9 | 1.7 | 0.0 | 8.4 | 76 | 4.3 | 5.6 | 0.0 | 21.4 | 14 |
| Livestock density (animals/km2) | 1.7 | 5.5 | 0.0 | 39.4 | 76 | 11.5 | 16.9 | 0.0 | 53.2 | 14 |
Appendix S1 for detailed description of GIS derived variables. See Table S1 in
1 The kill rate in unoccupied areas was zero, but we used the mean rate of 3.7 for occupied areas during analysis so that these areas did not bias the distribution for this variable.