Modelling connectivity around Oyster Leases in southeast Tasmania

Supervisory Team:

  • Primary supervisor: Dr Scott Hadley – IMAS Taroona
  • Co-supervisor: Dr Alison Turnball – IMAS Taroona
  • Additional supervisors: Ed Forbes – NRET Hobart

Brief project description:

Oyster leases in Tasmania are tightly regulated based on monitoring of water quality. Reported spills from Sewerage Treatment Plants (STP’s) for example, are monitored closely and a conservative approach is adopted in terms of risk of interaction with nearby oyster farms. However, local hydrodynamics play fundamental role in the transport of contaminants into the leases from source locations. Understanding the relative risk around an oyster lease from potential spills in a system can be examined using particle tracking models which are underpinned by hydrodynamic models of the receiving environment. Model output can be analyzed using metrics that establish connectivity.

CONNIE is a particle tracking model available via a web interface. Complex behaviour can be parameterized in CONNIE to simulate different types of particles and scenarios over extended intra/inter annual time scales can be run to look at seasonal/annual variability in particle trajectory. This information can be post-processed to incorporate connectivity metrics to provide a risk-based assessment of interaction between oyster leases and sources of contamination in the region. Connectivity metrics that are suitable for this type of decision-making, are well described in the literature.

This project will involve reviewing potential threats to oyster leases based on connectivity to sources of contamination. A model of connectivity around 1-3 oysters leases in southeast Tasmania will be developed in CONNIE and a risk based analysis used to assist in lease management.

Skills students will develop during this research project:

  • Developing conceptual models and then appropriate mathematical models to represent interactions in a coastal environment.
  • Connectivity modelling.
  • Understanding a client driven need, communicating with the client to ensure the need is correctly understood, and reporting back to the client on the outcome
  • Communicating the model outputs in an easy to understand method
Authorised by the Executive Director, Institute for Marine and Antarctic Studies
June 27, 2022