No more exotic caulerpa found at Leigh Harbour
Great news for residents of Leigh and Omaha. Since the discovery of a small clump of exotic caulerpa seaweed in Leigh Harbour / Omaha Cove this winter during Auckland Council’s routine dive surveillance, no more has been found in the harbour.
The finding was near the prized Cape Rodney-Okakari Point Marine Reserve (Goat Island)
The initial one-square-metre patch was controlled and removed by University of Auckland Leigh Laboratory divers, with no re-growth evident. Intensive searching was completed in October.
Exotic caulerpa was first found in New Zealand in July 2021 at Aotea Great Barrier Island. It has since been confirmed at Ahuahu Great Mercury Island, Te Rāwhiti Inlet in Northland, Kawau Island, Waiheke Island, Mokohinau Islands, Rakino Island, and Fantail Bay, Coromandel Peninsula.
A record of exotic caulerpa surveillance can be viewed here
While the complete and permanent removal of exotic caulerpa from New Zealand is not considered feasible with the current tools and the scale of the infestation, future efforts may include suppression (reducing density to lower the risk of spread) and eliminating it from specific sites
This is a first and great example of how local elimination can be achieved at a small scale. And how important regular surveillance is, to find these pests early enough to take action before it spreads.
This short video captures the journey of the people of Aotea Great Barrier Island, who are learning to live with exotic Caulerpa