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Villacorta-Rath, C.

Publications and source records attributed to Villacorta-Rath, C..

2 recordsLinked to original sources

Finding dugongs through environmental DNA: a complementary tool for population surveillance

Detecting dugongs at low densities remains a major challenge for conservation monitoring, particularly in remote or turbid coastal habitats where conventional surveys are difficult. Environmental DNA (eDNA) offers a complementary approach, but robust species-specific tools are needed before it can be confidently applied to dugong surveillance. We developed and analytically validated a quantitative PCR TaqMan assay for detecting dugong (Dugong dugon) eDNA and evaluated its performance across controlled aquarium conditions in Australia and Abu Dhabi, and wild populations in northern Australia and the Arabian/Persian Gulf. The assay detected dugong eDNA in aquarium and field samples, with Sanger sequencing confirming amplification of dugong mitochondrial DNA from positive field detections. Our assay provides a robust and geographically transferable tool for targeted dugong eDNA detection, performing reliably across contrasting coastal environments and widely separated populations. This approach can strengthen local-scale surveillance of low-density or difficult-to-detect dugong populations.

genetics↗

Invasive terrestrial invertebrate detection in water and soil using a targeted eDNA approach

O_LITerrestrial invasive invertebrates can rapidly colonize new areas, causing detrimental effects on biodiversity, economy, and lifestyle. Targeted environmental DNA (eDNA) methods could constitute an early detection tool given their sensitivity to small numbers of individuals. C_LIO_LIWe hypothesized that terrestrial runoff would transport eDNA from the land into adjacent water bodies and used the invasive yellow crazy ant (Anoplolepis gracilipes) as a model species to test this hypothesis. We collected water samples from four waterbodies adjacent to infestations following rainfall events for eDNA analysis. We also collected soil samples from areas of known infestations and tested five eDNA extraction methods to determine their efficiency to extract eDNA from soil. C_LIO_LIWater samples resulted in positive yellow crazy ant eDNA amplification (20-100% field replicates across all sites), even at one site located 300 m away from where ants had been detected visually. Soil samples resulted in a high percentage of false negatives when sampled from ant transit areas than from nest entrances. C_LIO_LIUnpurified DNA extracts from soil also resulted in false negative detections, and only after applying a purification step of DNA extracts, we detected yellow crazy ant eDNA in 40-100% of field replicates across all methods and sites. C_LIO_LIThis is the first study to empirically show that eDNA from a terrestrial invertebrate can be successfully isolated and amplified from adjacent or downstream waterbodies. Our results indicate that eDNA has the potential to be a useful method for detecting terrestrial invertebrates from soil and water. C_LI

genetics↗