A new survey of the mussel beds conducted by Kura Paul-Burke and her team in December 2024, has revealed that there are 45 million mussels growing across an area of 11 ha in the western Ōhiwa Harbour. The incredible increase in kuku, or green-lipped mussels, confirms Ōhiwa Harbour as the most successful mussel restoration effort across the country. The latest survey also showed that kuku are now beginning to grow up: 60 per cent are babies, 24 per cent teenagers, and 16 per cent adults. Back in July 2023 90 per cent of the mussel population were babies. The mussel bed size had also increased from 3.5 hectares in July 2023 to 11 hectares in December 2024. This exciting and hopeful discovery showed that prioritising mātauranga Māori alongside marine science, had managed to restore mussel numbers from a drop to only 80,000 in 2019 across the whole harbour, and appeared to reverse the decline.
‘The news of the 45 million mussels on the seafloor in Ōhiwa Harbour is what we have been working together with Kura and her team for all these years. It is brilliant news – for Ngāti Awa and the surrounding communities’ said Charlie Bluett, Customary Fisheries Manager, Te Rūnanga o Ngāti Awa. Kura Paul-Burke commented that ‘the work in Ōhiwa harbour is tangible evidence of mātauranga Māori as an important body of scientific knowledge. Its pragmatic methods and quantifiable results are helping to solve contemporary environmental problems. The growing mussel bed reflects the growing leadership and success of iwi-led shellfish restoration’.
The project continues to receive support from the Bay of Plenty Regional Council, Te Rūnanga o Ngāti Awa and the seven partners of the Ōhiwa Harbour Implementation Forum. Toi Iti, Bay of Plenty Regional Councillor and Chair of the Ōhiwa Harbour Implementation Forum pointed out: “Ensuring the mussels can continue to thrive is paramount. We are proud to have supported the mussel restoration project from the beginning’.
Three of the four mussel beds in Ōhiwa Harbour had disappeared in the last 13 years, affecting the ability of the harbour to function as a healthy ecosystem and mahinga kai (food basket) for local communities. The main reason for the mussel decline was an overabundance of predatory pātangaroa (sea stars) who were eating the mussels out of existence. A trial removing pātangaroa in 2020 resulted in the mussel population beginning to recover.
A section 186A temporary two-year harvesting closure has been installed by Te Rūnanga o Ngāti Awa and the Ministry of Fisheries over the mussel bed in the western Ōhiwa Harbour. It is hoped the rāhui will allow time for the new mussel bed to stabilise and continue to grow.
