Boaties and marine farmers around the Peninsula are urged to take extra care after recent discoveries of the marine pest fan worm (Sabella) in Coromandel Harbour.

This warning - which includes all vessels sailing, anchoring and mooring in the area, as well as marine farms – comes as Waikato Regional Council is ramping up funding to tackle marine pests.

A recreational boat which is heavily fouled with Mediterranean fanworm. The marine pest has recently been discovered in the Coromandel Harbour. Photo: H. Lass/Bay of Plenty Regional Council.

The regional council and Ministry for Primary Industries have been working together to eliminate the fan worm since it was first discovered in the harbour in 2013.

This first outbreak involved two infested barges from Auckland and was managed successfully in a joint operation. Ongoing monitoring was put in place.

WRC pest animals team leader Brett Bailey says the new finds highlight the importance of boaties and marine farmers to be vigilant and keep their equipment clean to avoid spreading this pest.

'It can grow prolifically, forming dense colonies, crowding out other marine life in harbours and potentially impacting aquaculture in the area.

'One of the best ways to stop the spread of fan worm is for boaties to have their moored boat hulls cleaned and have fresh anti-fouling paint applied regularly.

Brett adds: 'These actions will help stop fan worm getting a foothold in our region and protect our marine farms.”

Sabella was first reported in New Zealand in Lyttelton back in 2008, followed by another find in Auckland in 2009.

The species is well-established in Auckland, which is of concern as there is regular vessel movement between there and the Coromandel.

Monitoring for fan worm undertaken since the 2013 operation in Coromandel Harbour has involved divers inspecting moorings, the seafloor, vessels, mussel farms and structures .

Generally, only small, localised colonies of fan worms have been found and these have been removed immediately. But this autumn, monitoring picked up increased signs of the pest.

Six heavily fouled vessels in the harbour had Sabella on their hulls, while four fan worms were found at Hannafords Jetty.

All were immediately removed. More recently, it was reported there may be Sabella within a marine farm in the harbour. Closer checks are to be carried out.

'We ask that boaties and marine farmers work with us to help identify where any further fan worms are.”

As part of the WRC's recently approved Long Term Plan, $235,000 in funding will be provided in the next financial year to increase monitoring and management of marine pests in Coromandel Harbour and the wider Firth of Thames, with $185,000 a year thereafter.

For more information on fan worm, including photos, visit the Ministry for Primary Industries website at: www.biosecurity.govt.nz/pests/mediterranean-fanworm

If you have seen this pest, or spot any other unusual looking marine animal, report it to the MPI's pest and diseases hotline on 0800-809-966 or call the Waikato Regional Council on 0800-800-401.