Category
Poster - Basic
Description
The Peaks of Otter Salamander, Plethodon hubrichti, resides within a 15km stretch of the Blue Ridge Mountains in central Virginia. It is classified as a species of special concern in the state of Virginia. The Eastern red-backed salamander, Plethodon cinereus, has a broad range which overlaps that of P. hubrichti. In regions of sympatry, the competitive interactions between the two species may potentially influence the stress levels of the Peaks of Otter salamander. Such stress is earmarked by the release of corticosterone (CORT) which is the primary glucocorticoid released by the hypothalamic-pituitary-interrenal (HPI) axis in amphibians. This research focuses on examining the extent to which P. hubrichti experiences stress due to competition with P. cinereus through analysis of CORT and the scaled mass index (SMI) collected from Peaks of Otter salamanders in both allopatric and sympatric regions. A noninvasive waterborne technique is used to collect both baseline and agitation CORT concentrations from P. hubrichti. The hormone samples are then extracted and plated on an enzyme-linked immunosorbent assay (ELISA) for analysis. It is hypothesized that the baseline CORT for salamanders in allopatric habitats will be lower than their sympatric counterparts. Further, an inability to mount a physiological response to an acute stressor, displayed by lower agitation values, may indicate salamanders under chronic stress. Chronically stressed salamanders would suffer from weaker immune systems, lower reproduction, and reduced responsiveness to additional stressors, which lead to poorer health. Preliminary results show higher CORT values in agitation samples than in baseline samples, suggesting a functional HPI axis and no indication of chronic stress. Moreover, preliminary SMI data indicates higher salamander condition in sympatric sites than in allopatric sites, corroborating the CORT data. Further research will be conducted to process and analyze the remaining hormone samples to assess the validity of our initial results.
Evaluating competition effects on CORT and body condition in Plethodon hubrichti.
Poster - Basic
The Peaks of Otter Salamander, Plethodon hubrichti, resides within a 15km stretch of the Blue Ridge Mountains in central Virginia. It is classified as a species of special concern in the state of Virginia. The Eastern red-backed salamander, Plethodon cinereus, has a broad range which overlaps that of P. hubrichti. In regions of sympatry, the competitive interactions between the two species may potentially influence the stress levels of the Peaks of Otter salamander. Such stress is earmarked by the release of corticosterone (CORT) which is the primary glucocorticoid released by the hypothalamic-pituitary-interrenal (HPI) axis in amphibians. This research focuses on examining the extent to which P. hubrichti experiences stress due to competition with P. cinereus through analysis of CORT and the scaled mass index (SMI) collected from Peaks of Otter salamanders in both allopatric and sympatric regions. A noninvasive waterborne technique is used to collect both baseline and agitation CORT concentrations from P. hubrichti. The hormone samples are then extracted and plated on an enzyme-linked immunosorbent assay (ELISA) for analysis. It is hypothesized that the baseline CORT for salamanders in allopatric habitats will be lower than their sympatric counterparts. Further, an inability to mount a physiological response to an acute stressor, displayed by lower agitation values, may indicate salamanders under chronic stress. Chronically stressed salamanders would suffer from weaker immune systems, lower reproduction, and reduced responsiveness to additional stressors, which lead to poorer health. Preliminary results show higher CORT values in agitation samples than in baseline samples, suggesting a functional HPI axis and no indication of chronic stress. Moreover, preliminary SMI data indicates higher salamander condition in sympatric sites than in allopatric sites, corroborating the CORT data. Further research will be conducted to process and analyze the remaining hormone samples to assess the validity of our initial results.
Comments
Undergraduate