Integrating novel and traditional field technologies to quantify the activity cycles, behavior, and spatial ecology of a California species of special concern, Crotalus ruber

McAndrews, Emma C.

Department of Biology

San Diego State University

San Diego, California USA

emcandrews9826@sdsu.edu

Lemm, Jeffrey M.

Conservation Science and Wildlife Health

San Diego Zoo Wildlife Alliance

Escondido, California USA

Hanscom, Ryan J.

Department of Biology

San Diego State University

San Diego, California USA

The Red Diamond Rattlesnake, Crotalus ruber, is a large-bodied pitviper species with a restricted range in the United States. C. ruber is listed by the state of California as a "Species of Special Concern" due to heavy anthropogenic development of its preferred habitat in the coastal region of its range, the California Coastal Sage Scrub. Despite conservation concerns, little is known about this species' behavior compared to other rattlesnake species. Due to its behaviorally cryptic nature and the rugged terrain it inhabits, direct behavioral observations are often not feasible. Therefore, we implemented a combination of traditional radio telemetry tracking and animal-borne accelerometry biologging to understand previously inaccessible details of this species' activity and behavior. Over the course of two years, we radio-tracked a total of 26 C. ruber individuals (14 male, 12 female), including six individuals tracked consecutively across the two-year period. We opportunistically attached accelerometer biologging units to a total of 24 individuals across both years (14 male, 10 female). We recorded over ten thousand hours of acceleration data and five hundred hours of companion video footage of snakes in natural habitats (primarily through fixed videography). Using the data from our combined monitoring methods, we describe utilization distributions, site fidelity, overwintering patterns, activity cycles, and other unique behavioral observations of this at-risk and secretive species.