Table 2 Comparisons of observed thermal metrics to the thermal metrics derived from 100 random-walk migration path simulations for Western Rattlesnakes in British Columbia. Using thermal landscape maps, both observed thermal metrics and those of the simulated migrations were derived from the average incident solar radiation along the migration path for each migration category (Outgoing, Initial and Late stages). Forest snakes utilized forested habitats as the destination for their migration, while Open-Habitat snakes remained in sparsely-treed or open grasslands throughout the active season. Means are reported ±1 standard deviation, unless otherwise stated
From: Rattlesnake migrations and the implications of thermal landscapes
Comparison | Group | Outgoing Migration | Initial Stage | Late Stage |
|---|---|---|---|---|
A. Proportion of snakes occurring in the upper half of the distribution of the simulated migration paths | Forest snakes | 13/15 | 11/15 | 14/15 |
Open–Habitat snakes | 8/15 | 5/15 | 8/15 | |
|  | χ21 = 3.9, P = 0.046 | χ21 = 4.8, P = 0.028 | χ21 = 6.1, P = 0.013 | |
B. Average percentile scores of migration path values within values derived from the simulated migration paths | Forest snakes | 76.6 ± 25.4 | 68.5 ± 28.7 | 79.3 ± 18.8 |
Open–Habitat snakes | 51.1 ± 22.0 | 43.7 ± 18.0 | 50.2 ± 26.1 | |
|  | t27 = 2.95, P = 0.006 | t21 = 3.03, P = 0.006 | t28 = 3.46, P = 0.002 | |
C. Average probabilities (as determined by z-test scores) of migration path values as tested against a distribution of values derived from the simulated migration paths | Forest snakes | 0.24 ± 0.28 | 0.29 ± 0.26 | 0.25 ± 0.26 |
Open–Habitat snakes | 0.54 ± 0.30 | 0.68 ± 0.20 | 0.55 ± 0.27 | |
|  | t28 = −2.66, P = 0.013 | t26 = −4.65, P < 0.001 | t28 = −3.17, P = 0.004 |