Jodie Tiffany recently completed her PhD
Title of project: Investigating the Population Ecology of Cubozoan Jellyfish
Brief description of project:
Jellyfish of the Class Cubozoa have unique attributes such as complex eyes, great mobility and some have potent venom which can be lethal to humans. Envenomations from cubozoans and other stinging jellyfish can lead to a loss of tourism revenue. While the geographic ranges of cubozoan species are largely known, their population ecology has scarcely been studied.
The broad objective of this project is to use data on jellyfish behaviour and local currents to develop realistic models of population connectivity at spatial scales of hundreds of metres of tens of kilometers.
My research is focusing on two species: the relatively harmless Copula sivickisi and the potentially lethal Chironex fleckeri. Biophysical modelling will be used to investigate the spatial scale of cubozoan stocks and the source sink dynamics of cubozoan populations. Medusae cannot be treated as passive particles when modelled. Cubozoans possess balance sensory receptors and complex eyes. They are capable of perceiving and reacting to their surroundings. Many species, including C. fleckeri, are strong swimmers. Field observations and tank experiments will be conducted to quantify medusae swimming speed and behaviour. These data will be used to develop a behavioural model which will be coupled with a hydrodynamic model to generate the final biophysical model. Additionally, many cubozoan species are known to have patchy distributions at a fine spatial scale. Underwater video will be used to quantify abundance at an appropriately small scale. Finally, largely anecdotal evidence suggests that C. fleckeri polyps reside in estuaries during the dry season and metamorphose into medusae at the start of the wet season before moving into coastal waters. Statolith elemental chemistry will be used to test this long held paradigm.
Jodie has completed her PhD and is now a Post Doctoral Fellow working with Professor David Bellwood