Keeping fanworm out of Marlborough

Dive surveillance at Waikawa and Picton marinas has shown no sign of Mediterranean fanworm. Havelock Marina also received a clean bill of health.

The results boost confidence that Council’s biosecurity measures and monitoring have been effective in stopping this highly invasive marine pest.

However, a routine inspection in Waikawa Bay highlighted ongoing risks when divers found more than 200 fanworm on the keel of a boat that had arrived from Auckland. Most were juveniles, but two large individuals indicated the fanworm had been there for a while.

The vessel was fully wrapped - a proven-effective method for removing infestations - then hauled out for cleaning and antifouling.

Senior Biosecurity Officer Hayden Nott said the presence of a reproductive adult fanworm on the vessel increased the biosecurity risk for the mooring area.

“We are taking extra precautions by conducting surveys to ensure no new fanworm recruitment has occurred,” he said. “This incident reminded us that marine pest management is quite tricky because of the complexities of the marine environment.”

Council works closely with regional partners and Biosecurity New Zealand to prevent the spread of marine pests such as Mediterranean fanworm. Boaties are urged to keep their hulls clean and maintain antifouling to help protect the Sounds. If you notice anything unusual, contact the Council's Biosecurity team on 03 520 7400.