Climatic factors impacting thermoregulatory behaviours of coastal and inland rattlesnakes

Abstract

Conspecific animals living in multiple habitats may utilize different behaviours to survive and thrive in their environments. The Pacific rattlesnake (Crotalus oreganus), a generalist pit viper species, lives in a myriad of habitat types. We hypothesized that populations inhabiting hot, inland habitats and those in cool, coastal habitats would exhibit different behavioural strategies, especially those related to thermoregulation. Additionally, we determined whether environmental factors could be used as predictors of certain behaviours. We recorded environmental and behavioural data while radio-tracking adult, male rattlesnakes from two inland sites and two coastal sites throughout their active season. We found significant differences in thermoregulatory behaviour, with coastal snakes found more frequently above ground and in an active state than inland snakes. Additionally, wind, cloud cover, and air temperature were significant predictors of several snake behaviours. These results suggest that rattlesnakes exhibit plasticity in thermoregulatory behaviour.