Publication
Invasive terrestrial invertebrate detection in water and soil using a targeted eDNA approach
Publisher:
Cold Spring Harbor Laboratory
Date:
05-12-2022
DOI:
10.1101/2022.11.29.518289
Abstract: Terrestrial invasive invertebrates can rapidly colonize new areas, causing detrimental effects on bio ersity, economy, and lifestyle. Targeted environmental DNA (eDNA) methods could constitute an early detection tool given their sensitivity to small numbers of in iduals. We 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 s les from four waterbodies adjacent to infestations following rainfall events for eDNA analysis. We also collected soil s les from areas of known infestations and tested five eDNA extraction methods to determine their efficiency to extract eDNA from soil. Water s les resulted in positive yellow crazy ant eDNA lification (20–100% field replicates across all sites), even at one site located 300 m away from where ants had been detected visually. Soil s les resulted in a high percentage of false negatives when s led from ant transit areas than from nest entrances. Unpurified 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. This is the first study to empirically show that eDNA from a terrestrial invertebrate can be successfully isolated and lified 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.