Six Months On: How are the kūtai?
In February 2025, divers accompanied Ngāi Tai ki Tāmaki to return to our kūtai restoration sites at Te Pounui-o-Peretū (Ponui), Rotoroa, and the sites off the coast of Beachlands to see how the kūtai are settling in six months after deployment. While it’s still early days, this check-in gives us a first glimpse of how these kūtai are beginning to bed in.
Photos of Ngāi Tai ki Tāmaki and the divers at the 6-month check-in in February 2025.
So how are they doing?
Does it look promising? The short answer is there’s no big headline – but that’s okay. Kūtai restoration takes time, and this check-in is just one step on the journey. Like any new planting – whether it’s a native bush or a kūtai reef – it takes time for things to settle and grow. The kūtai are still finding their place, and while there are some signs of progress, we had tough diving conditions during the survey (visibility was poor), which made it harder to get consistent data.
In this type of survey, we monitor things like bed size and height, kūtai density and size, the number of empty paired shells (which tells us about mortality), and the presence of marine life and unwanted organisms.
Image of the kūtai upright and feeding at Rotoroa site. The red line is the transect along the length of the bed that the divers use to take measurements.
At the sites off Beachlands, we believe that kūtai numbers have dropped slightly – though it’s hard to tell if that reflects a real trend or just the natural ups and downs of the marine environment. Mortality is to be expected, especially early on. We saw an increase in empty paired shells at all sites, likely from natural losses rather than predators or storm damage.
Early survivability across sites appears to be in the ballpark of 75–85%, which is considered reasonable for this stage as the kūtai adjust to their new home.
As expected, it’s too soon to draw firm conclusions. The real test will come after 12 to 18 months, when the beds have had more time to settle and the patterns begin to reveal themselves.
Signs of Life
What’s especially heartening is the life starting to gather around the kūtai beds – especially at Rotoroa. Juvenile tāmure (snapper) and āhuruhuru (goatfish) were seen there, hinting that this site may already be acting as a nursery for young fish. Sponges and green algae are also appearing – great signs that the reef is beginning to support a wider web of life.
Photographs at the Rotoroa site of a sponge (left image) and āhuruhuru (goatfish) and red algae (right image).
At Te Pounui-o-Peretū, we saw some beautiful red algae. And while less diversity was spotted at the Beachlands sites, that may be more about the murky conditions on the day than an absence of marine life.
On the downside, we did find a few unwanted guests at Rotoroa – including Mediterranean fan worms, clubbed tunicates, wakame, and 11-armed starfish. The starfish weren’t present before deployment and may have been drawn to the new food offering. The good news is that no exotic caulerpa was found at any of the sites.
Testing the waters
This kūtai deployment aims to test site suitability. We placed 14 plots (about 2 tonnes of kūtai at each site) across a range of conditions in Ngāi Tai ki Tāmaki’s rohe moana to learn as much as we can. Over time, this will give us a strong foundation of knowledge to guide future restoration efforts.
Photos of Ngāi Tai ki Tāmaki on the kūtai deployment day in August 2024.
Kūtai are not just a species to monitor – they are taonga, with deep cultural and ecological significance. This mahi aligns with the values and aspirations of Ngāi Tai ki Tāmaki, and is grounded in shared kaitiakitanga. It’s a privilege to be part of this journey together, and we acknowledge the vision and leadership Ngāi Tai ki Tāmaki bring to this work.
What’s Next?
We’re due back in August 2025 for the 12-month survey. That’s when we expect to see more definitive trends – in kūtai growth, survival, and how these reefs are starting to interact with the ecosystems around them.
In the meantime, we’ll keep watching, learning, and sharing. And we’ll continue to hold this kaupapa with care – recognising that restoration is a long game, and that every kūtai, every site, and every relationship is part of a much bigger story.
Big mihi to the team that undertook this monitoring trip – Carina Sim Smith, Laurie Beamish, Pianina Kahui-McConnell, Shane Kelly, Ella Lis and Beau Masters.
Photo credits: Coast & Catchment and Katina Conomos.