Hibernating male lizards (Eremias argus) cleverly respond to insecticide exposure and warming temperatures: survival rate and physical condition cannot coexist

Abstract

Climate change and agricultural-chemicals are two major interacting threats to reptile populations. Similarly, hibernation is a huge challenge for reptiles, affecting their survival rate and reproduction. In this study, the effects of bifenthrin and heat on the hibernation of lizards were explored. Male Eremias argus (a native Chinese lizard) were exposed to environmental concentrations of bifenthrin (0.5 mg·kg⁻¹ and 5.0 mg·kg⁻¹) and different temperatures (5 °C and 8 °C) for 12 weeks during hibernation. Behavior, physical parameters, physiological, and biochemical indicators, metabolomics and lipidomics were measured to study the overwintering strategies of lizards under different stresses. The results indicate that bifenthrin induces oxidative stress and disrupts nitrogen metabolism, where metabolomic and lipidomic analyses revealed that bifenthrin exposure disrupts energy homeostasis and elevates disease susceptibility in these lizards. Lizards can change their hibernation depth by regulating testosterone levels in their bodies when hibernating in warmer temperatures. Frequently awakened lizards consume excessive energy, leading to poor physical condition, while deep hibernating lizards activate total antioxidant capacity to resist stress. Future climate warming and pesticide exposure will increases reptiles mortality during hibernation, compromising individual survival and population sustainability.