10 Jun 2017

Oyster cull won't stop parasite, says farmer

7:43 am on 10 June 2017

Culling farmed oysters in Stewart Island may appease people but won't get rid of a deadly parasite, one of the affected farmers says.

Flat oysters

Photo: Cawthron Institute

The Ministry for Primary Industries is ordering a cull of farmed oysters on the island to try to stop the spread of bonamia ostreae to wild stocks.

The parasite, lethal to the shellfish, was found on two oyster frams in Big Glory Bay a fortnight ago and there are fears it might spread to the nearby wild oyster population in Foveaux Strait.

The Bluff oyster industry has been pushing for a complete cull, saying it is the only possible way of stopping the infection from reaching Foveaux Strait.

But oyster farmer Rodney Clark said both wild and farmed flat oysters would have to be removed to eliminate the parasite.

Mr Clark said cull might appease people but it wouldn't be effective.

"Any measure you take sounds like a great measure but the reality is, [the parasite] is there. Have they any idea of the billions of litres of water that will have carried this parasite out of Big Glory Bay?"

Mr Clark said both wild and farmed flat oysters would have to be removed to eliminate the parasite. There were hundreds of thousands of flat oysters along the coastline, and removing them all would take years.

He said the decision to cull all of the area's flat oyster stock could mean the end of his 14-year-old business.

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