Welcome to Oyster Health Sydney!
This comes to you from the Aquatic Animal Health team in the School of Veterinary Science at The University of Sydney. We are affiliated with The University of Sydney Marine Studies Institute, the Sydney Institute for Infectious Diseases and the Sydney Institute of Agriculture. We hope you enjoy this site, the opportunity it provides to view our research, and the means it gives you to offer advice, comments and suggestions to assist our research program.
We believe that healthy oysters are central to a sustainable oyster industry, the coastal community it supports and to healthy estuaries. But how do you assess health, and what factors determine whether a healthy batch of oysters will remain healthy in the presence of disease threats? How does the environment and Australia’s biosecurity system affect oysters? How can oysters be managed to minimise the risk of losses due to infectious diseases? Can we immunise oysters? Why not just breed for disease resistance? These are some of the questions we try to answer in our multidisciplinary research program.
We work closely with oyster growers and benefit from their great insight about the best methods for oyster farming. This knowledge includes many traditional practices to avoid common diseases. Unfortunately the emergence of new diseases has increased the risks of farming oysters and this is where science must step up to meet the challenge. Quick fixes do not exist, and those who promise them must eventually produce evidence.
The Australian oyster industry faces many challenges due to climate (fire, flood and climate change) and human-associated environmental conflicts (urban estuarine pollution, agricultural runoff). Superimposed are infectious diseases like Pacific Oyster Mortality Syndrome (POMS), which is caused by a marine herpesvirus and QX disease caused by a parasite. This blog will be focussed for some time on POMS. However, the principles we use in POMS research are directly applicable to QX.
Fundamental research on the life history of infectious disease (epidemiology, using tools of microbiology, virology, parasitology, immunology and pathology) should accompany applied research on approaches such as husbandry and genetic selection so that efforts are focussed and lead to measurable outcomes rather than anecdotes. Sadly, we know exponentially more about POMS, a disease that has been present in Australia only since 2010 than we know about QX disease, which has been present for more than 50 years, due to poor research leadership on the latter.
We communicate our findings in a variety of ways, including via this website. We ensure rigorous standards in research and ensure that our findings are publicly available for assessment by industry and the international scientific community. We aim to publish in scientific journals in a timely manner to encourage uptake and independent verification of our results in other settings – please look at “Scientific Publications”. We are accessible and meet with farmers, farming associations and media. We have produced Fact Sheets that may be useful in the face of a POMS disease outbreak, to assist with disinfection, prevention of mortalities in hatcheries, and to help reduce losses and salvage value when an outbreak occurs on farm – please look at NEW:POMS Fact Sheets.
Despite progress in the husbandry of oysters, and claims about improved genetics, it is currently impossible to restock a farm with spat in a POMS endemic area and be confident about their survival. Results from commercial trials in NSW in which POMS disease events were to be monitored closely in 2018 cannot be properly interpreted. For POMS, environmental conditions, specifically low water temperatures, do favour survival in some estuaries particularly those in the south and in Tasmania in most years, but climate change will remove this advantage over time.
The oyster industries require ongoing research and development for new innovations and future prosperity, but without leadership to define endemic disease research needs, and appropriate resourcing and supervision of suitably qualified research teams, the default position of biosecurity crisis management during disease flare ups will prevail.
Emeritus Professor Richard Whittington
University of Sydney,
Camden, NSW Australia
Last updated: November 2022