An Ecophysiological Assessment of Extinction Risk from Climate Change of the lizard Barisia imbricata (Squamata: Anguidae).

Abstract Climate change is one of the most pressing challenges for ectotherms due to their dependence on environmental temperature. Extirpation of populations of lizards have already been reported, including endemic species occurring in the mountains of Central México. Here, we characterize the thermal ecology of a montane, viviparous lizard species, Barisia imbricata. In addition, we use thermal and physiological traits to predict the persistence of the species in face of climate change. We collected individuals from two populations at its lower and upper elevational limits, recorded field body temperature (Tb), operative environmental temperatures (Te), preferred body temperature (Tpref) and the thermal sensitivity of endurance. We calculated the hours of activity (ha) and hours of restriction (hr) using a mechanistic-ecophysiological model. We then applied a species distribution model that integrates core ecophysiological traits (Tb, Tpref, thermal performance breadth, optimal temperature for performance, critical thermal maximum and minimum) with climate variables to determine potential shifts in habitat occupancy. Finally, we used a mechanistic niche model that includes estimates of hr and ha to predict the probability of persistence of the species under three scenarios of climate change between now and by 2070. We found that B. imbricata has a broad performance breadth, which suggests it is a thermal generalist, and is capable of activity across a broad range of Te. The mechanistic-ecophysiological niche model predicts that B. imbricata faces serious distributional restrictions at low elevations, but populations at higher elevations should persist if the habitat remains intact.