Life in the Slow Lane: Stress Responses in Plethodontid Salamanders

Abstract

Abstract Plethodontid salamanders are specialized for a low-energy lifestyle, offering an interesting model for studying vertebrate stress responses. Furthermore, in an increasingly changing environment, it is important to understand how plethodontid salamanders respond to a variety of different stressors. Here, I review findings from my research group on the impact of various stressors on behavior and physiology in three species of plethodontid salamanders. A robust response to putative stressors was a decrease in locomotory activity, which was found after exposure to handling, predator kairomones, and acidic environments. The change in locomotory activity was not related to changes in corticosterone (CORT), a glucocorticoid hormone (GC) considered to be a hallmark of the vertebrate stress response. The uncoupling of CORT from stress-induced behavior might relate to the fact that decreased locomotory activity is not energetically costly, while CORT is a metabolic hormone that functions to mobilize glucos...