Kelp Gardeners

What is the project all about? The Kelp Gardeners are setting out to pilot an approach to reversing the occurrence of urchin barrens habitat in the Hauraki Gulf Marine Park and beyond.

If we can establish on a small scale that the approach of human intervention to control urchin populations leads to the regeneration of seaweed habitat, larger-scale projects that would naturally follow have the potential to make a big positive contribution to the health of shallow sub-tidal rocky reef marine ecosystems with the Hauraki Gulf.

What form will it take? The project is a limited area pilot of controlling urchin populations to reverse the phenomena known as urchin barrens. We aim to establish that this approach will promote the regeneration of seaweed and kelp habitat in the Hauraki Gulf.

The scientific basis for our project will be overseen by Dr Tim Haggitt and collaborators from the University of Auckland.

How will it work? Simply put, humans will replace the actions of the currently-absent natural predators of urchins — such as mature snapper and rock lobster. A team of volunteer divers and snorkelers will regularly visit the pilot sites located near Enclosure Bay and Palm Beach on Waiheke Island, and remove the urchins there, to reduce their numbers down to levels that would potentially represent a more balanced marine environment.

How will we reduce the urchin numbers? By picking them up and moving them out of range of the experiment sites, or by taking them ashore and giving them as food to the local marae and other organisations on the island that run community meal services and community kitchens.

How many urchins will the project take? Volunteer divers will stick to the daily catch limit of 50 urchins per person, which should achieve our aims over the limited area of our pilot sites. (Subsequent projects run over a wider scale would need to apply for exemptions to the daily catch limits, but this is beyond the scope of our current project).

What else is involved? Hand in hand with this conservation work is the work of telling the story to the island community, our stakeholders, and other interested communities around the Hauraki Gulf. So while some of our work will be in the water working with urchins, some of it will be on social media, some will be in mainstream media, and some will involve getting out into our communities and telling the many stories of the state of our Hauraki Gulf and what we all can be doing about it.

Would you like to get involved? Visit

Pin It on Pinterest