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Updated: May 13, 2026
06:01
Cortisol Extraction from Sturgeon Fin and Jawbone Matrices
Published on: September 10, 2019
Pond acidification may explain differences in corticosterone among salamander populations
David L Chambers1, Jeremy M Wojdak, Pang Du
1Department of Biological Sciences, , Virginia Tech, Blacksburg, VA 24061, USA
Physiological and Biochemical Zoology : PBZ
|February 26, 2013
Summary
Environmental factors like pH and nitrate impact the stress hormone corticosterone in Jefferson salamander larvae. Understanding these physiological tolerances aids in predicting species distribution changes due to environmental stressors.
Area of Science:
- Ecology
- Environmental Science
- Physiology
Background:
- Physiological tolerances are crucial for species distribution and abundance.
- The hormonal stress response, involving glucocorticoids, is a conserved vertebrate mechanism for coping with environmental stressors.
Purpose of the Study:
- To assess baseline and stress-induced corticosterone concentrations in Jefferson's salamander larvae across natural populations.
- To investigate the relationship between environmental pond parameters and corticosterone levels.
- To experimentally determine the effect of pH on corticosterone concentrations.
Main Methods:
- Field survey of eight natural breeding populations of Ambystoma jeffersonianum, measuring baseline and acute stress-induced corticosterone.
- Analysis of environmental pond parameters (pH, nitrate, temperature).
- Outdoor mesocosm experiment manipulating pH to assess corticosterone response.
Main Results:
- Significant differences in baseline and stress-induced corticosterone concentrations were found among ponds.
- Baseline and stress-induced corticosterone were negatively related to pH and positively related to nitrate.
- Elevated baseline corticosterone was observed in larvae exposed to low pH treatments (5-5.8).
Conclusions:
- Environmental factors, particularly pH and nitrate, influence the physiological stress response in Jefferson's salamanders.
- Combined field and experimental approaches are effective for understanding environmental impacts on species.
- This research provides insights into predicting species distribution shifts under environmental change.
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