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ABSTRACT The Indo‐Pacific lionfish,Pterois volitans,is an invasive species in the western Atlantic. Since its introduction to Florida in the early 1980s, populations have surged with lionfish now found from North Carolina to Venezuela. As their range expands, these generalist predators threaten native fauna, and while they are primarily a marine species, their tolerance for low salinity conditions may allow them to expand into sensitive estuarine habitats undetected. Traditional approaches for tracking invasive species such as direct observation or trapping are impractical over large spatial scales, making environmental DNA (eDNA) an attractive alternative. Molecular assays, such as those employing quantitative polymerase chain reaction (qPCR), amplify low copy number DNA fragments in environmental samples and are increasingly employed as a complement to traditional methods for the detection of invasive species. Currently, there is one published PCR assay for the detection of lionfish eDNA. However, the specificity of this assay is unverified, and the critical performance parameters limit of detection (LOD) and limit of quantification (LOQ) have not been established. Here we evaluate the efficacy of this assay and show that it is likely to result in false negatives in the western Atlantic. As an alternative, we developed a new TaqMan probe‐based qPCR assay that is species‐specific forP. volitansand highly sensitive with a LOD of 12 copies per reaction and a LOQ of 598 copies per reaction. While our assay does not amplify the closely relatedP. miles, which was also introduced in the western Atlantic, the low prevalence of this species in the invasive population means our assay is effective for most monitoring purposes. We conclude that our assay is a robust method for the detection of lionfish and can be employed in any habitat, offering new opportunities for controlling the spread of invasive lionfish. 

Transmissible spongiform encephalopathy, or prion disease, poses a serious threat to wildlife; however, the susceptibility of apex predators is still being assessed. We investigated variation in the prion protein gene in Florida panthers (Puma concolor coryi) and found that admixture from Central American pumas probably introduced a novel, albeit benign, prion allele. 

Soil carbon (C) storage is a globally important ecosystem service with the potential to contribute to climate change mitigation. Wetlands are heavily researched hot spots for soil C storage. Despite the growing number of wetland soil C inventories, most studies focus only on total C quantification; there is limited application of methods that evaluate differences in C stability and vulnerability to mineralization within the C pool. Permanganate oxidizable C (POXC) is a well-established soil health indicator in agriculture shown to be sensitive to changing conditions or management regimes and may prove equally informative in wetland studies. This research quantified POXC in six diverse wetland soils that differed greatly in organic matter content and spanned both freshwater and saltwater habitats, then evaluated the relationship between POXC and basic soil C properties, microbial indicators, and physical and chemical fractionation metrics. Results showed POXC averaged ∼ 37 times greater in wetlands than upland agricultural soils, but was less robust in differentiating between individual wetlands than total C or organic matter content. Rather, the ratio of POXC to soil organic C may be a more informative metric for evaluating the proportion of slightly processed C in wetland soils. Significant correlations were found between POXC and almost all other soil properties measured, suggesting POXC could be a rapid, reliable, and economical proxy for other analyses. Overall, POXC shows potential for providing novel information about wetland soil C stability, but requires additional research to improve interpretability. Applying POXC analysis in time series data collection and before-after-control impact experiments may be particularly informative for wetland management.