Mr Scott Morrissey1, Prof Dean Jerry1, Prof Michael Kingsford1
1College of Science and Engineering, James Cook University, Townsville, Australia
Biography:
Scott is a PhD candidate with the Reef and Ocean Ecology Laboratory group at James Cook University in Townsville, North Queensland. His PhD has focused on the assessment and implementation of eDNA as an ecological survey tool to enhance detection and further understanding of deadly box jellyfish.
Abstract:
Chironex fleckeri is considered the most dangerous species of box jellyfish, posing considerable threats to both human health and commercial enterprise. Environmental DNA (eDNA) has emerged as a powerful and cost-effective tool for detecting this elusive jellyfish, overcoming challenges due to their elusive nature, transparency, and spatial and temporal variability. Furthermore, eDNA has shown considerable promise as an ecological survey tool, enabling the detection of benthic life-history stages and providing insights into the population stock structure of this taxa. However, understanding of eDNA transport in dynamic marine environments remains limited and this knowledge is crucial for enhancing sampling efforts and interpretation of C. fleckeri detections.
As a result, we utilised biophysical models, integrating C. fleckeri eDNA decay rates, to simulate the transport and dispersal patterns of eDNA under various conditions. This was undertaken for an open coastal bay where ecological and eDNA sampling data exists for C. fleckeri. With these models, we aimed to understand the following. 1) eDNA transport within and outside of the bay, 2) the influence of differing wind and tidal conditions upon eDNA transport, and 3) how modelled transport compares to empirical field measurements. The findings provided key insights into the spatial extent of C. fleckeri eDNA and how environmental forcings influence eDNA transport. This understanding is essential for refining eDNA sampling strategies, improving detection reliability, and enhancing the utility of eDNA as an ecological survey and management tool for problematic jellyfish. Additionally, these findings underscore the importance of considering local environmental conditions in eDNA studies.