Oyster farming contributes almost $100 million to the Australian economy each year and is especially important in NSW, where it represents 30 per cent of all seafood production.
The predominantly family-owned industry is, however, constantly endangered by outbreaks of devastating and unpredictable oyster disease events.
In the past 20 years, disease has led to mass oyster death and, ultimately, the closure of harvesting regions across NSW and Tasmania, costing the industry many millions of dollars.
Now, funding from an Australian Research Council (ARC) linkage grant brings together scientists from the University of Technology Sydney (UTS), the University of NSW (UNSW) and the NSW Department of Primary Industries (NSW DPI) with the aim of giving the Australian oyster industry unprecedented capacity to forecast disease outbreaks.
Associate Professor Justin Seymour, an ARC future fellow in the UTS Climate Change Cluster (C3), and Dr Maurizio Labbate, from the UTS ithree institute, will lead the collaboration to identify the main ecological and environmental drivers of NSW oyster disease outbreaks.
“The causes of oyster disease are complex. Although water temperature, rainfall, pollution, algal blooms and shifts in oyster microbiome are potential catalysts for outbreaks, a clear understanding of what causes oyster disease remains elusive,” Associate Professor Seymour says.
“Consequently, we can’t make predictions about future disease outbreaks and that makes it difficult to manage infections and develop mitigation strategies,” he says.
The research team will use new tools to highlight connections in the data for a better understanding of the relationships between disease and environmental factors. The approach has been applied in the human health and microbial ecology disciplines, but this is the first time it has been used to investigate aquaculture disease.
Pacific oysters, the dominant species harvested in Australia and highly susceptible to Pacific Oyster Mortality Syndrome (POMS), will be distributed across the Georges and Hawkesbury rivers, where oyster disease events have occurred, and in Port Stephens, which has remained disease-free. By taking advantage of existing NSW DPI research activities, the project will measure temporal patterns in the two estuaries.
“Rather than being stimulated by a single factor, oyster infections such as POMS are triggered by a complex suite of interacting processes,” Dr Labbate says.
“The project will rely on both network analysis and species distribution models to describe the biotic and abiotic conditions that are likely to trigger a disease event. This information will then be used to create a predictive model that can forecast when an oyster disease outbreak is likely to occur,” he says.
The project was awarded $570,000 of ARC funding over four years, together with almost $430,000 from Ausgem (Australian Centre for Genomic Epidemiological Microbiology), a partnership between the NSW DPI Elizabeth Macarthur Agricultural Institute and the ithree institute.
“The linkage project is an example of how Ausgem has helped to bring together and support an expert team of scientists with the combined skills to reveal the key mechanisms behind oyster disease outbreaks,” says Professor Steven Djordjevic, ithree institute professor of infectious disease and senior ithree Ausgem leader.
NSW DPI oyster health expert Dr Cheryl Jenkins says the DPI has a responsibility to ensure aquaculture develops in a productive, sustainable and biosecure manner.
“This research will allow NSW DPI to inform growers when and why diseases are likely to occur and to use this information to provide advice on how to better manage stocks to avoid disease outbreaks. We hope this research will safeguard the future of a primary industry that is the cornerstone of many coastal communities,” she says.
Other members of the team include UNSW microbial ecologist Dr Mark Brown and NSW DPI oyster ecologist Dr Wayne O’Connor.