Dr Michael Stat1, Mr Jarrod Gunn, Dr Dave Harasti1, Dr Victoria Cole1
1University of Newcastle, Callghan, Australia
The spatial ecology of eDNA in aquatic environments has implications for interpreting the distribution of species. Estuaries can support a variety of habitats that provide shelter and food for different taxa, yet the hydrodynamics and tidal flow in these systems presents challenges to resolving the habitat preference of any given species. To investigate whether there is spatial structure in eDNA sampled from a highly dynamic intertidal estuary, we characterised the fish assemblages identified in water collected from a range of habitats in Port Stephens. Water was collected at high tide from oyster, seagrass, mangrove, and sediment sites, as well as from a recently restored oyster reef, and metabarcoding of 12S and 16S amplicons used to infer the fish present. We also sampled fish diversity using mini BRUVs, to enable a comparison and to evaluate the effectiveness of eDNA in detecting the fish present. A significantly higher number of fish was detected using eDNA than BRUVs, some of which can be explained by the transport of eDNA in water throughout the estuary. However, when filtering the eDNA datasets for fish that were frequently detected (in 3 or more of the 6 replicates at a site), significant differences in richness and composition can be resolved between habitats. Our results suggest that depending on how eDNA datasets are filtered, information on fish biodiversity present in the estuary as well as those associated with distinct habitats is achievable.
Biography:
Dr Michael Stat is a lecturer at the University of Newcastle where he leads an Environmental genomics lab. Michael is a molecular ecologist that has worked on coral reef symbiosis and adaptation for over 15 years, and more recently on using eDNA to understand patterns of biodiversity and the interaction of species. Michael has a variety of current projects that utilise eDNA to understand the ecology of organisms and the structure of marine and terrestrial biota, changes to biodiversity due to impacts, as well towards understanding the feeding ecology of species.