Waiheakeans should be on the lookout for caulerpa and report any sightings outside of known incursions to MPI. This thick patch of caulerpa was found in Aotea Great Barrier. In the seas around Waiheke, it tends to be sparser. Photo Irene Middleton

“Whether we are marine users or kaimoana eaters or not – and I’m not – it’s not about us as individuals. It’s not about me. It’s about my grandchildren, your grandchildren. It’s greater than oneself.” Ngāti Pāoa’s Blair Anderson is speaking about the threat that invasive caulerpa seaweed poses to Aotearoa New Zealand’s environment, economy and way of life. 

The Pou Rāhui iwi collective, comprised of Ngāti Pāoa, Ngāti Hei, Ngāti Tamaterā  and Ngāi Tai ki Tāmaki, are proposing a ramped-up approach to combat the spread of caulerpa, described by experts as “the most serious marine biosecurity incursion in our lifetime”.

Caulerpa was first detected in Aotearoa New Zealand waters in 2021 at Aotea Great Barrier and has since spread to other locations, including Waiheke in 2023. Up until now, it had only been found in one location on Waiheke, Onetangi Bay. But Blair says the latest NIWA dive found patches of it at Hākaimangō/Owhanake. 

• Tessa King

Full story in this week’s Gulf News

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