In partnership with Ngāti Whātua Ōrākei, the Revive Our Gulf project is working to establish kūtai beds and improve the health and mauri / life essence of  Ōkahu Bay. 

For Ngāti Whātua Ōrākei (hapū), this project forms part of a long-term, intergenerational environmental restoration kaupapa / project.  This includes re-planting of the whenua / land and improving the health of the Waitematā.  For the hapū, this is rooted in a need to re-establish kaitiakitanga / guardianship and the physical and spiritual connection to the whenua / land and rohe moana / sea, after a sorry history of gradual land confiscation and desecration.

Only two generations ago, Ōkahu Bay was the blue pantry or pātaka kai of the hapū, with plentiful shellfish and an ocean that was said to be ‘red with snapper’.    By establishing kūtai beds in the Waitematā it is hoped that one day the hapū can return to the traditional cultural practices of kohinga kai / food gathering from their tribal waters.   This has great cultural significance for mana whenua as providing kai / food  for manuhiri / guests is an important aspect of manaakitanga / hospitality and caring for guests.

The current project builds upon work spearheaded by the late Richelle Kahui-McConnell, working closely with Ngāti Whātua Ōrākei whānau and two generations of the Tamaariki whānau—Tamaiti and his daughters Moana and Donna Tamaariki.  Working with the scientific community and early Revive Our Gulf volunteers, this group conducted a number of projects looking at feasibility of kūtai beds in the bay.  As Moana Tamaariki-Pohe, a long-term kaitiaki and advocate for the bay describes it, the goal is to create a bay that ‘smells different, tastes different, looks different, feels different.’ 

“Waters fit to swim in at all times, with thriving marine eco-systems that provide sustainable kaimoana resource for the Ngāti Whātua Ōrākei community who have a strong daily presence in and on the bay as users and kaitiaki”

Ngāti Whātua Ōrākei long-term ecological restoration plan (Kahui-McConnell 2012)

Projects included a small pilot kūtai drop in 2014 and a pylon kūtai ‘wrap’ to attract spat in 2017.  Also instrumental to improving the health of the bay was lobbying Auckland Council to seek the removal of 154 boat moorings from the bay in 2019.  The removal of the boats reduced pollution from anti-fouling hull coatings and opened the bay up for safer recreational use such as waka ama (outrigger canoeing).   The foundational work on kūtai restoration, and clearing the bay of boats, now allows for this next phase.

The plan is to establish a number of 10 tonne kūtai beds. Initially six beds will be established, with each bed around 10m x 10m and containing approx. 700,000 adult green-lipped kūtai.  Three beds will be placed on a shell base and three beds on bare sediment, allowing us to compare survival in these two environments.  

Ōkahu bay experimental design
In the current phase of the project six 10 tonne kūtai beds (that’s approx 700,000 kūtai per bed!) will be established in Ōkahu bay out by the breakwater pylons. Three of the beds will be on shell and three on sediment. Rimurimu / kelp will also be cultivated as part of the project. Graphic: Shaun Lee

We will be tracking a number of metrics including:  

  • survival and growth of the kūtai (on shell vs. sediment)
  • the size and density of the beds
  • the appearance of any new kūtai (recruitment)
  • the presence of other species including crustaceans, worms, oysters, sea squirts, juvenile fish and predators such as starfish.

Our hope is that the kūtai beds will thrive, and that we start to see increased biodiversity within 6–12 months. All going well, the plan is to expand the site to include four additional 10 tonnes beds in 2022. We aim to use this as a flagship project and a working model for other kūtai restoration projects across the Hauraki Gulf / Tīkapa Moana / Te Moanaui-ā-Toi.

There is much to learn about how we can create healthy, self-sustaining reef habitats at scale and Ōkahu Bay will be a ‘living laboratory’ helping us to develop a winning formula for kūtai restoration.  

The Ōkahu Bay project page

About the Revive Our Gulf project