MARINE scientists are working overtime to identify a mystery illness that has decimated Port Stephens Pacific oyster crops.
Millions of Pacific oysters have died suddenly over the past two months. Almost all of a batch of a million juvenile Pacific oysters imported from Tasmania by fourth generation grower Geoff Diemar died recently.
"It doesn't seem to matter if they are imported from interstate, produced at a local hatchery or are wild catch," he said. "The ones that seem to be surviving best are the wild catch but it depends on where they are in the port."
Pacific oysters are not sold from the port during summer. The disease does not appear to have affected other marine species, including the native Sydney rock oyster.
A NSW Food Authority spokeswoman said testing had shown there were no human health implications regarding water quality or the consumption of seafood from the area.
"Oysters, fish and other seafood remain safe to eat," she said.
"The authority recommends people to always thoroughly cook any recreationally caught seafood."
The Department of Primary Industries is also working with the Environment Protection Authority on the investigation.
Pacific oysters first appeared in Port Stephens in 1985 and have been grown legally in the port since 1989. The Pacific oyster industry employs dozens of growers and is worth about $5 million per annum.
A meeting between government agencies and growers is expected to be held when analytical test results come back in the next fortnight.