Habitat use, spatial ecology, and management of Southwestern Speckled Rattlesnakes (Crotalus pyrrhus) in the Tinajas Altas Mountains of Yuma County, Arizona
Grimsley-Padron, Ashley
Wildlife Contracts Branch Arizona Game and Fish Department
Phoenix, Arizona USA
Current address: Wildlife Management Division
Arkansas Game and Fish Commission
Springdale, Arkansas USA
Smith, Austin B.
Information Systems Branch
Arizona Game and Fish Department
Phoenix, Arizona USA
Current address: Haub School of Environment and Natural Resources
University of Wyoming
Laramie, Wyoming USA
Piest, Linden A
Region 4 Arizona Game and Fish Department
Yuma, Arizona USA
Ingraldi, Michael F.
Wildlife Contracts Branch
Arizona Game and Fish Department
Phoenix, Arizona USA
Jones, Thomas R.
Terrestrial Wildlife Branch
Arizona Game & Fish Department
Phoenix, Arizona USA
Illegal hunting and wildlife trafficking is a growing and prominent threat to species worldwide. An isolated population of Southwestern Speckled Rattlesnakes (Crotalus pyrrhus) occurs in the Tinajas Altas Mountains of Yuma County, Arizona, USA. Individuals in this population are sought after in the pet trade because of their unique white-cream coloration. The ecology of this population is not well understood. We used telemetry to study habitat use, home range size, and movement patterns of 19 C. pyrrhus in this population from October 2017 to May 2019. We calculated home ranges with both Minimum Convex Polygons and Kernel Density Estimates. We most often found snakes on slopes (65%) using boulders as their primary cover (57%). We commonly observed snakes using Elephant Tree (Bursera microphylla) and Catclaw Acacia (Senegalia greggii) as vegetation cover, with low visibility for most observations. We observed annual variation in use of habitat type and daily variation in both cover type and visibility. Minimum Convex Polygon Estimates ranged from 0.91–13.74 ha. We found no significant difference in movements, activity areas, or core areas between males and females or between a near-average and an unusually wet winter season. This study provides novel habitat and spatial ecological information for guiding the management and conservation practices of this distinct population of C. pyrrhus.