WATERSHED WATCH: COMBINING EDNA AND COMMUNITY SCIENCE TO MONITOR AQUATIC SPECIES OF CONCERN

Climate change, habitat fragmentation, and human movement are increasing the spread of invasive species, harming biodiversity, ecosystem services, and public health. Traditional biodiversity monitoring is expensive, slow, and limited in coverage, leading to incomplete data. Here, we developed molecular tools- using environmental DNA (eDNA) technologies- to record the presence of invasive zoonotic mosquitoes in Ontario and Quebec regions of Canada and compare its diversity to traditional trapping methods. We tested six eDNA sampling methods at three locations across 30 freshwater waterbodies to identify protocols suitable for community scientists. All sampling methods recovered detectable mosquito eDNA, with passive eDNA samplers (PeDS) achieving the highest detection rate at 85%. Salt-preserved water samples (SALT) and traditional on-site filtration followed at 62% detection rate. SALT yielded the highest eDNA concentration per unit of water volume. The location of sampling (inlet, outlet, shoreline) within each water had no significant differences in detection rates. Community scientists successfully deployed PEDS and SALT, showing their high applicability. Our approach combines emerging eDNA technology and community science, enabling non-invasive, scalable monitoring of low-biomass organisms like mosquitoes. It can be used in volunteer lake monitoring programs to expand biodiversity knowledge and track species of concern, including invasive and rare taxa, offering a valuable tool for freshwater ecosystem surveillance.

Presentation Preference: Standard Oral (12 Minutes)

Primary Presenter: Genevieve D'Avignon, Université de Sherbrooke (genevieve.davignon@usherbrooke.ca)

Authors:

Geneviève D'Avignon, Université de Sherbrooke, Groupe de recherche interuniversitaire en limnologie (GRIL)  (genevieve.davignon@usherbrooke.ca)

Madeleine Aucoin, McGill University  (madeleine.aucoin@mail.mcgill.ca)

Hélène Pfister, Concordia University, Groupe de recherche interuniversitaire en limnologie (GRIL)  (helene.pfister@concordia.ca)

Asher Woodhead, Concordia University  (asher.woodhead@concordia.ca)

Irene Gregory-Eaves, McGill University  (irene.gregory-eaves@mcgill.ca)

David Walsh, Concordia University  (david.walsh@concordia.ca)

Antoinette Ludwig, Agence de la santé publique du Canada, Laboratoire National de Microbiologie  (antoinette.ludwig@phac-aspc.gc.ca)

Yannick Huot, Université de Sherbrooke  (Yannick.Huot@usherbrooke.ca)