Exploring the intersection of behavior and physiology in Crotalus viridis across their range through biologging

Hanscom, Ryan J.

rhanscom6545@sdsu.edu

Department of Biology

San Diego State University

San Diego, California USA

Department of Evolution, Ecology, and Organismal Biology

University of California

Riverside, California USA

Department of Natural Sciences

University of South Carolina Beaufort

Beaufort, South Carolina USA

Hill, Jessica L.

Sukumaran, Jeet

Department of Biology

San Diego State University

San Diego, California USA

Higham, Timothy E.

Department of Evolution, Ecology, and Organismal Biology

University of California

Riverside, California USA

Clark, Rulon W.

Department of Biology

San Diego State University

San Diego, California USA

Ectotherms, which make up the vast majority of terrestrial animal biodiversity, are particularly susceptible to shifts in climate and temperature regimes because temperature directly influences their physiological processes, as well as their locomotion, activity patterns, and behavioral strategies. In many cases, physiological constraints directly inform behavioral choices, making the interplay between physiology and behavior crucial for understanding how ectotherms navigate the challenges of fluctuating thermal environments. Here, we integrated behavioral and physiological data in free-ranging rattlesnakes to understand how distinct thermal environments shape the physiological mechanisms driving behavioral strategies. To do this, we studied three populations of prairie rattlesnakes (Crotalus viridis) across a latitudinal gradient using an integrated biologging approach to continuously monitor temperature and movement patterns through accelerometry and temperature loggers. We found that movement rates in the southern population were restricted to a narrow temperature range, whereas the northern population exhibited movement across a broader range of temperatures, suggesting reduced thermal constraints on activity. These findings highlight the utility of using novel biologging technologies to understand how local thermal environments shape the relationship between physiology and behavior in ectotherms.