Oral Presentation Society of Environmental Toxicology and Chemistry Australasia 2023

Community-led passive eDNA monitoring in GBR waterways (#131)

Sarah Stephenson 1 , Sharon Hook 1 , Cindy Bessey 2 , Doug Bearham 2 , Michael Warne 3
  1. CSIRO, Battery Point, TASMANIA, Australia
  2. Environment, CSIRO, Perth, WA, Australia
  3. Reef Catchments Science Partnership, School of Earth and Environmental Sciences, University of Queensland, , Brisbane, Queensland, Australia

Multiple stressors such as sediments, nutrients, pesticides are causing concern for the health of the catchments of the Great Barrier Reef (GBR). A variety of monitoring approaches are required to assess the potential impact of these stressors. For this citizen science project we have engaged with community groups in North Queensland. Citizens such as Indigenous groups, farmers and other volunteers have chosen sites for water quality and biological analysis.

The main aim of the research is to test: what are the ecological and environmental conditions in healthy and impacted waterways and determine if there are any links between water quality and community structure. We also aim to determine if having citizen scientists deploy environmental DNA (eDNA) samplers is an effective way of monitoring habitats. The citizens provided a list of key species that were of community concern for the Wet Tropics and Mackay - Whitsundays regions. An eDNA approach was applied using metabarcoding to monitor the selected sites. From consultation with communities, broad markers for fish and crustacea were identified as the key eDNA assays to serve their priorities. For ease of sampling and safety of volunteers, novel, passive eDNA samplers were designed in-house and tested for efficacy of eDNA capture.

In parallel with water quality and sediment sampling, the volunteers deployed the passive eDNA samplers to identify community structure and the richness of the fish and crustacea upstream of each site. Sampling was repeated at three separate times - once prior the wet, once during the wet, and once post heavy rains had passed. The metabarcoded fish and crustacea eDNA community structure results will be delivered to the community groups along with the water quality data at each site to investigate potential correlations.