National award for scientist
A Tasmanian scientist has been honoured with a prestigious national award for helping to unlock the mystery of a deadly virus decimating the oyster industry.
Pacific Oyster Mortality Syndrome – or POMS as it is commonly called – is devastating.
POMS is a viral infection that causes oysters to suddenly fall asleep with their shells open. Now vulnerable to predators and other environmental hazards, they are often dead within the day.
The virus is deadly to oysters but harmless to oyster eaters.
When POMS hit Tasmania three summers ago some farmers lost 90% of their oysters in a matter of days.
However, optimism is slowly returning to the industry and the work of Tasmanian scientist, Dr Sarah Ugalde, is making a big contribution.
“It looks like we are finally having some headway with this terrible disease,” Dr Ugalde said.
“The oyster industry is just starting to recover.
“There is finally light at the end of the tunnel, although there is still a long way to go.”
While its effects are crystal clear, POMS itself remains a mystery: no-one knows what causes it, how it is spread, and most importantly how to stop it in its tracks.
Dr Ugalde - and the research team - from the Institute for Marine and Antarctic Studies (IMAS), is working to answer those questions.
For this work, Dr Ugalde has just been awarded the Vice Chancellors Award run by Universities Australia.
“I am very honoured to receive such an important award which supports the communication of critical research,” Dr Ugalde said.
The virus was first detected in France 11 years ago and arrived on Australia’s shores – near Sydney – in 2010.
In February 2016, without any warning, POMS turned up at Pittwater Lagoon in southern Tasmania. It quickly spread as far north as the east coast, infecting 60% of the state’s main growing areas along the way.
One of those hardest hit was second generation oyster farmer, Josh Poke, who owns the Estuarine Oyster Company at Pittwater.
“We lost one million dollars' worth of oysters in the space of just six weeks during that terrible summer,” Mr Poke said.
“That is almost one and a half million mature oysters.
“It was heart-breaking.”
Before the POMS outbreak Tasmania produced four million dozen oysters each year, with a farm gate value of $24 million.
“After POMS Tasmania’s oyster production went down by 45%,” Mr Poke added.
Since that 2016 outbreak, Dr Ugalde has been working closely with local oyster farmers like Josh Poke and conducting experiments in the field.
“Scientists need to understand how to farm, and farmers need to understand science,” she said.
As there is no cure for the virus which is carried by many small marine animals such as sea snails and mussels, Dr Ugalde’s work is focused on containing POMS through improved management practices.
“Eradication of POMS in the natural environment is not an option,” she said.
“The main thing we can do is learn how to manage it.
“Like any disease it takes a lot of time to figure out what works - and what doesn't.”
A key trigger for POMS appears to be oyster stress.
Dr Ugalde's research found oyster handling was one of the most important ways to reduce that stress and keep the oysters happy. Put simply, they need to be treated gently.
Timing is also crucial.
The POMS virus is activated in warm waters - above 18 degrees Celsius - and Dr Ugalde said oysters should never be moved when it is hot.
Oysters also need to be stocked at low densities, giving them plenty of space to grow.
“This research is helping farmers learn how to cultivate oysters in POMS-affected areas,” Dr Ugalde said.
“What they can do for the oysters. How they can de-activate this disease.”
Meantime, as Tasmania’s oyster industry wraps up its third season under the cloud of this deadly virus, it is clear that progress is being made.
Reflecting on the last few years, Sue Grau, from Oysters Tasmania, said: “This disease is still killing oysters and the industry is still recovering.
“However, the good news is we are adapting and changing and learning how to live with POMS.
“In the meantime, let’s not forget that Tasmanian oysters are the best in the world, and POMS does not affect human consumption.
“So, if there is one message we need to get out it is this: just keep eating our wonderful oysters.”
Image courtesy of Dr Sarah Ugalde
11 April 2018