A disease known as Bonamia ostreae has been found in wild Bluff oysters for the first time in an area of Foveaux Strait.
Biosecurity New Zealand says the three infected oysters were discovered in a sample site in the south-western area of the Strait as part of a routine surveillance programme. No infection was found in the other five sample sites.
The wild oyster industry is currently in the middle of this year’s harvest season, but commercial operators can continue fishing with a likely ‘no take’ zone in the affected area.
No other monitored sites have been affected at this stage.
Biosecurity manager Cath Duthie says “commercial Bluff oyster fishers have not reported any sign of the disease and we’ve not detected it in five years of six-monthly surveillance sampling in the area”.
Bonamia ostreae is not considered a food safety risk and fresh, good quality Bluff oysters are still safe to eat. But left unmanaged, the parasite can significantly reduce the population over time.
Biosecurity New Zealand has been running an extensive programme to keep the disease out of the wild oyster population.
Bonamia ostreae was first discovered in the Marlborough Sounds in 2015 and two years later in flat oysters in Big Glory Bay on Stewart Island.