Influence of Physical Stress, Sex, and Body Size on Metabolic Rates of Ozark Zigzag Salamanders, Plethodon Angusticlavius


Kyle M. Shull

Date of Graduation

Fall 2007


Master of Science in Biology



Committee Chair

Alicia Mathis


Ozark zigzag salamanders (Plethodon angusticlavius) are exposed to a variety of stressors, each eliciting a combination of behavioral and physiological responses. One response is an increase in oxygen consumption rate. Individuals were physically stressed to simulate a predatory attack, and oxygen consumption was measured following stress using a constant respirometry apparatus. For large salamanders (SVL ≥ 32 mm), stressed individuals had higher metabolic rates, but there was no significant effect of sex or significant interaction between sex and treatment. For small salamanders (SVL < 32 mm), there was no significant effect of treatment; sample sizes of males were too small to allow for tests of sex effects for small salamanders. The lack of treatment effect for small salamanders was unexpected because previous experiments with a related species showed stronger responses to stress by smaller salamanders than by larger salamanders. While other factors such as temperature, reproductive state in females, and body surface area for cutaneous respiration may have affected the results, it is most likely that the salamander's activity during the simulated attack caused the increase in oxygen consumption. Further testing is needed to distinguish if the response is a result of predation stress or simply an increase in physical activity.


oxygen compution, metabolic rate, Plethodon angusticlavius, red-backed salamander, stress

Subject Categories



© Kyle M. Shull