Aquaculture news

Flat oyster
31 May 2017

Flat oyster parasite found at Stewart Island

Cawthron Institute scientists are well-placed to respond to the discovery of Bonamia ostreae at oyster farms on Stewart Island.

Bonamia ostreae is a parasite that poses substantial threat to flat oysters, and this afternoon the Ministry of Primary Industries (MPI) confirmed they have detected it at two Stewart Island farms.

Cawthron Institute Aquaculture Group Manager, Dr Serean Adams explained the need for research in this area. Dr Adams said, “Bonamia ostreae was discovered at the top of the South Island two years ago and has now been found at Stewart Island farms.

“We know European flat oysters have been impacted by this pathogen, and indications from overseas research suggests selective breeding for resilience is possible. Much of our current knowledge is based on the experiences of countries with related oyster species.

“There’s a need for targeted research on the New Zealand species and we hope to work with Government agencies and industry on this.”

New Zealand flat oysters

Cawthron has a wealth of relevant experience; having successfully bred herpes resilient Pacific oysters following the 2010 ostreid herpes (OsHV-1) virus outbreak.

“With our background in shellfish health and selective breeding, the Cawthron Aquaculture Group is well-placed to respond to the Bonamia ostreae parasite.

“The ostreid herpes virus almost wiped out New Zealand’s Pacific oyster stocks in 2010 so our team worked fast to breed strong, virus resilient families. Now in 2017, the New Zealand Pacific oyster industry is thriving,” Dr Adams said.

Cawthron’s Aquaculture Group is currently working on a research strategy document for the New Zealand flat oyster aquaculture industry, as part of the Ministry of Business, Innovation and Employment (MBIE) cultured shellfish programme.

They operate a purpose-built aquaculture research facility in Nelson known as the Cawthron Aquaculture Park, the largest of its kind in the Southern Hemisphere.

Cawthron Institute recognises the vigilance of the MPI’s surveillance programme and their efforts to limit further Bonamia ostreae spread.