Cubozoan jellyfish are elusive by nature and as a result many challenges exist with respect to detection, which is of concern considering the threat they pose to humans. The polyps of the deadly Chironex fleckeri represent the longest-lived stage of jellyfish and are the source of medusa (adult form of Chironex fleckeri). However, there is almost no information available on the benthic polyp stages of this species.
This project will apply the innovative genetic technique, environmental DNA (eDNA) sampling to detect Chironex fleckeri polys in the waters off Mapoon in far norther Queensland. Should this technique prove successful it will remove the need to physically observe jellyfish in a location and will allow for quicker and increased detection. The study also allows for investigation into the ecology of the polyp life history stage of this jellyfish which currently, is almost unknown.
Further, oceanographic modelling, that incorporates the decay of eDNA, will provide greater knowledge of ‘DNA’ halos’ that signals proximity to targeted polyp beds and jellyfish aggregations.
The specific aims of this project are as follows;
1. Determine the rate of decay of eDNA for Chironex fleckeri medusa.
2. Demonstrate experimentally in the laboratory and field that we can detect the presence/absence and relative abundance of Chironex fleckeri medusae and polyps using eDNA.
3. Undertake oceanographic modelling of eDNA halos incorporating eDNA decay to determine dispersal distances of eDNA from point-sources (e.g. beds of polyps).
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