Winter behavior of rattlesnakes at Indio Mountains Research Station, Hudspeth County, Texas

Mata-Silva, Vicente

vmata@utep.edu

Department of Biological Sciences

University of Texas at El Paso

El Paso, Texas USA

Da Cunha, Oceane

Rocha, Arturo

DeSantis, Dominic L.

Department of Biological and Environmental Sciences

Georgia College and State University

Milledgeville, Georgia USA

Rattlesnakes spend a considerable amount of time below the surface during the winter period (the inactive period) at both high elevations and high latitudes. Therefore, our goal for this study is to determine the characteristics of their overwintering sites, which are critical for their survival in the Chihuahuan Desert of the Trans-Pecos region. Herein, we present overwintering data from individuals of Western Diamond-backed Rattlesnakes (Crotalus atrox), Rock Rattlesnakes (C. lepidus), and Eastern Black-tailed Rattlesnakes (C. molossus) from Indio Mountains Research Station (IMRS), located in far west Texas. These individuals were monitored during different winters since 2007 to present with radio telemetry. Until now, our data showed that snakes overwinter singly and their winter shelters are located inside their home ranges. Most snakes of C. atrox and C. ornatus selected west facing slopes, and most individuals of C. lepidus selected southeast facing slopes. A PCA analysis showed that the winter shelters of C. lepidus and C. ornatus are more similar when compared to those selected by C. atrox. In general, all three species spent five months (November-March) overwintering at IMRS, and on average, C. lepidus lost 8.5%, C. ornatus 15.9%, and C. atrox 26.9% of their body mass. The ongoing gathering of data will allow us for a more in-depth analysis and identify possible patterns regarding their overwintering behavior with respect to sex, age classes, body temperature, and underground activity on this region of the Chihuahuan Desert, which experiences relatively mild winters.