The Hauraki Gulf / Tīkpapa Moana / Te Moananui ā Toi has long been a vital marine ecosystem, once teeming with vast beds of green-lipped mussels (kūtai) and diverse marine life. But decades of destructive fishing practices, land-based runoff, and population growth have taken their toll. Add in climate change, marine heatwaves, acidifying waters, and frequent storms, and the Gulf is facing serious threats.
Today, the Revive Our Gulf project is working tirelessly to crack the code for restoring soft-sediment kūtai beds at scale, aiming to restore the mauri of this significant water body. This ambitious effort, in partnership with Ngāti Manuhiri Settlement Trust, highlights the ecological and cultural importance of kūtai while bringing together communities and fostering collective action.
Below the surface
Revive Our Gulf’s mission is to re-mussel the Hauraki Gulf, focusing on the pivotal role kūtai play in enhancing water quality, supporting marine biodiversity, and bolstering climate resilience. By filtering sediments, nutrients, metals, and contaminants, kūtai contribute significantly to cleaner and healthier waters. Their reefs provide essential structures on the seafloor, promoting a diverse marine ecosystem and offering protection against storm surges.
At the turn of the 20th century, the Gulf’s inner regions were covered with over 600km² of kūtai beds—equivalent to 80,000 rugby fields. However, extensive dredging for mussels began in 1910, and by the mid-1960s, the fishery had collapsed. Despite over six decades passing, natural recovery has not occurred. Today, the Revive Our Gulf project aims to reverse this decline through a series of strategic deployments and restoration initiatives to build knowledge on how to restore these vital habitats, at scale.
Whakatō Kūtai: A partnership with Ngāti Manuhiri
The latest deployment, conducted in partnership with the Ngāti Manuhiri Settlement Trust, is a testament to the collaborative spirit driving this project. This is the second such deployment, building on the substantial kūtai reefs created in 2022 near Moturekareka and Motuketekete Islands. These initial efforts have provided valuable insights, with kūtai at Moturekareka showing promising growth, while those at Motuketekete faced challenges due to sedimentation and deployment methods.
This year, 100 tonnes of adult kūtai (approximately 7 million kūtai!) have been sourced from a Coromandel Mussel Farm and placed in Motuora and Martins Bay. Guided by Ngāti Manuhiri’s extensive knowledge of their rohe and detailed ecological surveys, the project will examine conditions for kūtai survival and growth. Additionally, the maramataka (Māori lunar calendar) has been used to select optimal deployment times.
Kotahitanga: The heart of the kaupapa
One of the most inspiring aspects of this kaupapa is how it unites people. It’s not just an ecological restoration project but a collective movement driven by a shared desire to heal and protect the moana for future generations. The kaupapa is ambitious, reflecting the urgent need to address Te Moananui ā Toi’s degraded state.
Restoration begins with people. He tangata. He tangata. He tangata. Developing trust and sharing knowledge are crucial steps. This season, the focus has been on strengthening connections and knowledge across the Revive Our Gulf whānau. From site selection discussions to engaging with the mussel farmers and observing the kūtai harvest process, every step has been collaborative.
The recent deployment saw seamless coordination, with four boats working together on the water, ensuring safety and pride in the kaupapa. This collective effort lays a solid foundation for restoration.
Looking ahead
Over the next 2-3 years, and particularly in the next six months, the kūtai will be closely monitored to assess their survival and impact on the ecosystem. This period will provide answers to critical questions and inevitably raise new ones, driving further research and refinement of restoration techniques.
Sharing this journey with funding partners, government officials, and other stakeholders has been a highlight. Hosting guests on the water and discussing the kaupapa in situ has provided invaluable opportunities to deepen understanding and support for the project.
The Revive Our Gulf project is a collaborative effort involving the Mussel Reef Restoration Trust, the University of Auckland Institute of Marine Science, The Nature Conservancy Aotearoa New Zealand, and iwi, hapū, and whānau. With three Tangata Whenua partners – Ngāti Manuhiri Settlement Trust, Ngāti Whātua Ōrākei, and Ngāi Tai ki Tāmaki – the project leverages both scientific expertise and mātauranga Māori to create conditions for large-scale restoration.
The Challenge Fund, spearheaded by The Nature Conservancy, has been pivotal in fundraising efforts, with Foundation North matching donations dollar for dollar. So far, $1 million has been raised towards this work, with the goal of raising an additional $1 million by March 2025.
For more information on how to support the restoration efforts and contribute to the health of the Gulf, please get in touch with us.
Big mihi to the photographers: Shaun Lee, Ben Sarten, Will Proser