New oyster on the horizon for Queensland

Queensland’s oyster industry has been struggling in recent years, with the traditional Sydney Rock oysters being killed off by disease.

Griffith Australian Rivers Institute’s Carmel McDougall is working on creating a sustainable solution. She has suggested replacing the Sydney Rock oyster, which is susceptible to QX disease, with a disease-resistant species called the Blacklip oyster.

QX disease causes Sydney Rock oysters to die in warmer weather, and has resulted in commercial losses worth millions of dollars. This new tropical species thrives in warm waters which could open up Queensland’s northern coastline for oyster farming, as opposed to just the south-east corner.

“The Blacklip doesn’t succumb to the same disease….so the interest is in looking at whether or not it survives in Queensland conditions,” McDougall said.

She also noted that the growth rate of the Blacklip oyster is significantly faster, which would appeal to farmers, who can reduce turnover times and distribute their products more quickly.

McDougall has a history of working with oysters and pearl development, and she plans to use her molecular genetics experience to develop a more widely available, edible oyster. Specifically, she aims to improve the survival rates of Blacklip oyster and work out exactly what distinguishes them from the Sydney Rock oyster.

“We are looking at the question by using genetics. We are trying to look at what genes are expressed differently [between] the Blacklip oyster and the Sydney Rock oyster at the stage where the Blacklip oyster is really dying off in the hatcheries,” she said.

The research will also take into account dietary variables such as the algae they are being fed, as well as environmental factors such as the temperature and the salinity, to establish how to increase numbers.

The experiment, which is part of an Advance Queensland Fellowship, began at the start of the spawning season in October. McDougall is working in association with Aquafarms Queensland on the first batch of Blacklip Oysters in Hervey Bay.

Although McDougall does not eat oysters herself, others have told her they are equally as delicious as the Sydney Rock oyster.

She explained: “Apparently there is no difference between the two, it is really well accepted by consumers and if you look at them, they essentially look the same except the shell just has a bit of a black margin around the outside of the shell.”

If the experiment is successful, the research could revolutionise aquaculture and help the dwindling oyster farm industry.

“Oysters are one of the most environmentally friendly species to farm, and if we can figure out how to produce the Blacklip efficiently in the hatchery this could be a massive boost for sustainable aquaculture in Queensland,” McDougall said.