Understanding the processes shaping responses of native species to environmental perturbations, such as the introduction of non-native species, will allow us to better manage such impacts. The imported Red Fire Ant, Solenopsis invicta, invaded the United States ∼70 years ago and co-occurs with Fence Lizards (Sceloporus undulatus) in portions of their range. Lizards from fire ant-invaded populations have longer hind limbs which more effectively remove ants and increase survival following fire ant attack. Prior research on this system suggests that this difference in relative hind limb length (RHL) is fixed at birth; however, RHL is a plastic trait in other lizard species and could help Fence Lizards survive. Lizards from invaded sites are more likely to climb when attacked by fire ants or when stressed (i.e., have elevated levels of corticosterone) than are lizards from uninvaded sites. We tested for climbing-induced plasticity in RHL by manipulating whether or not Fence Lizards had to climb raised platforms to bask. This testing revealed that increased climbing did not affect RHL at maturity (34 weeks of age) or hind limb growth rates. This result was unaffected by initial limb length, differential survival, source population, or ambient or body temperature of the lizards, suggesting that the amount of climbing does not plastically affect the RHL of S. undulatus.