With an ability to pack in 1,000 individuals per square meter, Mediterranean fanworm makes it difficult for other species in the vicinity to survive. Imagine it doing that in some of our pristine dive spots. It filters large volumes of water, feeding on nutrients and plankton, including the larvae of our much loved recreational fish species. Large numbers attached to your hull could be costing you a whole heap more in fuel too.

This species is known to be in the following locations in Northland, Auckland, Coromandel (western side), Canterbury, Gisborne. If you find it outside this area, please report it.

Whangaroa Harbour, Opua, Whangārei Harbour, Hauraki Gulf including Waitematā Harbour and Firth of Thames, Port Fitzroy area and Wairahi Arm Aotea / Great Barrier Is, western side of Coromandel Peninsula and Square Top Island, Lyttelton Harbour.

This list is correct to the best of our knowledge at the time of publishing – for a full list of marine pest locations, please go to the Marine Biosecurity Porthole.

From the team at Clean Below? Good to Go – visit marinepests.nz to get everything you need to know about marine pests ID, boats, rules and more.