Graduation Year
2022
Document Type
Thesis
Degree
M.S.
Degree Name
Master of Science (M.S.)
Degree Granting Department
Biology (Integrative Biology)
Major Professor
Alison Gainsbury, Ph.D.
Committee Member
Carlos Santamaria, Ph.D.
Committee Member
Michelle Green, Ph.D.
Keywords
Florida ecosystems, monitoring, surveys, threatened species
Abstract
1. Accurate information about species range declines is the cornerstone of effective conservation when habitat loss drives biodiversity loss. The Eastern Indigo snake (Drymarchon couperi) is an apex predator in Florida and, like many other native Florida species, is threatened by widespread habitat destruction. Environmental DNA (eDNA) monitoring of this elusive snake would provide a low-risk and low-cost approach to expand our knowledge of the species’ range and distribution.
2. We designed and tested an eDNA assay that can detect the presence of Eastern Indigo snake from soil samples of their natural habitat. This assay was tested in vitro and in situ and used to analyze the degradation of eDNA between soil seeded with and without feces over time under different temperature and humidity scenarios.
3. We successfully amplified the Indigo snake Cytochrome B gene at concentrations as low as 0.003ng/µL and detected it in 2 of 30 in situ field soil samples. No eDNA was detected in the temporary pond samples (n = 20). After seeding soil with feces (n = 11), Indigo snake eDNA was detectable for 10 days (9% of samples). From the soil removed from snake enclosures (n = 30), DNA was also detectable for 10 days (3% of samples). Temperature and humidity had no effect on the degradation of eDNA in this experiment.
4. Synthesis and applications: Conservation and management of the Indigo snake can be bolstered by the addition of eDNA presence monitoring. Soil-based eDNA may enable and/or improve monitoring of many terrestrial species, providing concrete information about species range changes due to multiple anthropogenic stressors.
Scholar Commons Citation
Galbraith, Emily K., "Design and assessment of a novel eDNA survey method for the Eastern Indigo Snake (Drymarchon couperi)" (2022). USF Tampa Graduate Theses and Dissertations.
https://digitalcommons.usf.edu/etd/10385
