Assessing the reliability of eDNA as a tool for invasive non-native species and biodiversity monitoring in freshwater ecosystems

Dr Jo James¹, Dr Paul Stebbing¹, Miss Rachel Naden², Dr  Steph Bradbeer², Dr Ben Aston²

¹Apem Ltd, , United Kingdom, ²Yorkshire Water, , United Kingdom

With increasing global pressure to monitor Invasive and Non-Native Species (INNS) there is a demand to develop effective and efficient screening tools. Over recent years there has been growing interest in the use of environmental DNA (eDNA) as a means of species monitoring both to detect INNS and to carry out population biodiversity assessments using metabarcoding. However, as the application of eDNA in ecology is still relatively in its infancy there are few taxa for which eDNA is a regulator-approved detection method. Furthermore, the comparability between the results of eDNA surveys and those conducted using traditional methods is poorly understood. Here, we collected water samples from various lentic and lotic sites across Yorkshire, England that were tested for invasive signal crayfish (Pacifastacus leniusculus) using qPCR and metabarcoding (the results of which were compared). Metabarcoding assays for fish and invertebrates were also carried out on these samples. The results of the eDNA analyses were then compared to those of traditional surveys conducted in tandem, as well as to historic species distribution data where available. Overall, the comparability of the eDNA and traditional survey results varied between taxa being highly consistent for fish and signal crayfish but less so for the wider invertebrate community. This study provides baseline data, the type of which, is essential to build an evidence base for assessing the reliability of eDNA as a method for detecting species within freshwater ecosystems.

Biography:

Jo is a Principal Consultant at APEM specialising in  freshwater ecology. Since working at APEM Jo has managed several projects relating to Invasive and Non-Native Species (INNS) and the use of eDNA for INNS detection as well as for wider biodiversity monitoring. Prior to joining APEM Jo worked working at the National Fisheries Services in the Environment Agency (England) overseeing their molecular disease diagnostic laboratories. This followed on from her PhD which she completed at Cardiff University (Wales) investigating the impacts of invasive crayfish on freshwater ecosystems. As part of this Jo carried out molecular screening of several non-native crayfish species for the presence of the Aphanomyces astaci, the causative agent of crayfish plague.