THE EFFECTS OF WILDFIRES ON PREDATION RISK, PERCH SELECTION, AND BACKGROUND-MATCHING IN WESTERN FENCE LIZARDS

Fires are a naturally occurring phenomenon, driving a range of behavioral, reproductive, and morphological adaptations in wildlife. However, we are now living in a new geological epoch—the Pyrocene—characterized by human-induced extreme fire behavior. This shift results in a need to understand how animals survive and adapt in post-fire environments. In this study, we investigated the following questions: (1) Does predation risk increase in burned habitats after a fire? (2) How does dorsal darkness morphology vary between burned and unburned habitats? and (3) Do animals select perches that enhance their background-matching in post-fire environments? We used the Western Fence Lizard (Sceloporus occidentalis) for this work, studying populations in and around the perimeter of the Fairview Fire, which burned over 11,000 ha in 2022. Using artificial clay models of lizards, we found that predation risk was higher in burned habitats compared to unburned habitats. Furthermore, we found that lizard dorsal darkness was not greater in burned sites compared to unburned sites. Instead, substrate darkness had a greater impact on lizard dorsal darkness across all habitats with lizards appearing darker on burned perches compared to unburned ones. However, lizards preferred to perch on unburned wood within burned sites, leading to an average dorsal darkness comparable to lizards in unburned sites. Interestingly, lizards’ background matching increased with substrate darkness, implying they are most camouflaged against burned substrates, but they do not prefer to use these substrates. Overall, our results show that despite higher predation risk, lizards do not exhibit strong behavioral shifts to use perches that enhance camouflage in recently burned habitats, suggesting there may be complex trade-offs affecting their behavioral decisions. Our findings provide valuable insights into the behaviors of animals in post-fire landscapes and add to the urgent need to understand the consequences wildfires have on animal behavior.