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Gaia Meigs-Friend

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Bullseye snakehead, Channa marulius, was first detected in 2000 in the southern Florida town of Tamarac and has been expanding its geographic range. Environmental DNA (eDNA) analysis is a newly-developed technique used to non-invasively detect cryptic or low-density species, or those that are logistically difficult to study. Genetic material shed into the environment through tissue and body fluids is concentrated from water samples and analyzed for the presence of target species eDNA. To help delineate bullseye snakehead’s geographic range, we developed and validated a species-specific eDNA assay for both quantitative and droplet digital PCR (ddPCR). We then used ddPCR to assess 16 locations in southeast Florida...
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Environmental DNA (eDNA) detection is a rapidly expanding technique used to non-invasively detect cryptic, low density, or logistically difficult-to-study species, such as imperiled manatees. Genetic material shed into the environment through tissue and body fluids is concentrated from water samples and analyzed for the presence of targeted eDNA. To help delineate manatee habitat ranges, high use areas, and seasonal population changes, a cytochrome-b quantitative PCR and state-of-the-art droplet digital PCR (ddPCR) eDNA assay was developed for the three extant and vulnerable manatee species: both subspecies of the West Indian manatee (Florida and Antillean), the African manatee and Amazonian manatee. Occurrence...
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Environmental DNA water samples were collected in the Greater Everglades Ecosystem between May 20-22, 2019 and analyzed to estimate Burmese python (Python bivittatus) occurrence. Twenty-eight sites were sampled in the Greater Everglades Ecosystem, with 5 field replicate samples per site, for a total of 140 water samples collected. Python eDNA was detected at 25 of the 28 sampling sites using Droplet Digital PCR amplification. Data either are not available or have limited availability owing to sensitivity concerns. Contact the Wetland and Aquatic Research Center for more information.
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Data files for manuscript "Improving eDNA yield and inhibitor reduction through increased water volumes and modified multi-filter isolation techniques". These include the results of different treatments for inhibitor removal from a water sample and DNA yield quantities from such tests. Environmental DNA (eDNA) methods detect genetic material that is shed into the environment through skin cells and excrement by plants and animals. These methods are increasingly being applied to detect imperiled and invasive species for range assessment and occurrence estimates. To improve the recovery and detection of eDNA, we tested and optimized three basic protocols to 1) assess whether eDNA concentration increase in a linear...
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Environmental DNA (eDNA) detection of invasive species can be used to delimit occupied ranges and estimate probabilities to inform management decisions. Environmental DNA is shed into the environment through skin cells and bodily fluids and can be detected in water samples collected from lakes, rivers, and swamps. In south Florida, invasive Burmese pythons occupy much of the Greater Everglades in mostly inaccessible habitat and are credited with causing severe declines of native species’ populations. Detection of Burmese pythons by traditional methods, such as trapping and visual searching, have been largely ineffective, making eDNA a superior method for differentiating invaded habitat. We adapted a quantitative...
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