Restoring Aotearoa New Zealand's Seagrass Meadows

Cawthron Institute is leading a multi-year research programme, Restore the Meadows, to pioneer seagrass restoration techniques for Aotearoa New Zealand. We are working with mana whenua, philanthropic foundations, businesses, government, industry, and environmental groups. Our goal is to support biodiversity, improve water quality, and help mitigate climate change.

What we’ve achieved

During the first three years of the project, our research focused on understanding seagrass reproduction and restoration site selection. We investigated:

When and where seagrass flowering occurs
How to collect and process seeds
How to store and germinate seeds
How to identify suitable restoration sites
How to successfully transplant adult plants

This work culminated in the creation of a blueprint for seed-based seagrass restoration – a critical foundation for large-scale recovery of seagrass meadows across Aotearoa.

What’s next

The current phase of the programme is moving from seeds to plants. We are now trialling techniques for:

Growing seagrass seedlings in nursery conditions
Establishing seagrass in the wild through direct seed sowing of seeds and planting seedlings

These efforts are essential steps toward large-scale, sustainable restoration of seagrass ecosystems.

Funders

Clare Foundation, OneFortyOne Limited, Port Nelson, Friends of Nelson Haven and Tasman Bay, University of Waikato, Nelson City Council.

Previous funding: Westpac NZ Government Innovation Fund, the Simplicity Foundation, Catalyst Fund, Ngā Pae o te Māramatanga and Cawthron Institute Trust Board.

Collaborators: University of Waikato (Joanne Ellis, Hazel Needham), Deakin University (Craig Sherman), Central Queensland University (Emma Jackson) and University of Auckland (Conrad Pilditch), Tasman Bay Guardians, Love Rimurimu.

We also want to thank mana whenua for supporting our research.

Why seagrass matters

Seagrass is a marine flowering plant with long green leaves and underground rhizomes that anchor it against tides and currents. In Aotearoa, our single species, Nanzostera muelleri, grows in estuaries, harbours, and coastal meadows – and has recently been shown to commonly flower and produce seeds.

Seagrass meadows are vital ecosystems. They:

Improve water quality
Provide habitat and food for fisheries
Support coastal resilience and biodiversity
Store carbon and help mitigate climate change

Yet, around the world and here in Aotearoa, seagrass is in decline due to human activities.

Get involved

We are looking to partner with organisations and investors who want to support this innovative restoration work. Please contact us for more information about funding and sponsorship opportunities.

Stay connected by signing up for our Restore the Meadows newsletter. In our quarterly updates, we’ll share project progress and ways you can help restore seagrass in Aotearoa.

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Seagrass flowers with protruding stigma (used to catch pollen for fertilisation).

Representatives of the project’s partner organisations at Nelson Haven in July 2022. From left: Allanagh Rivers – General Manager of Infrastructure and Environment at Port Nelson, Kylie Reeves – Communications Manager at OneFortyOne Ltd, Brent Guild – Executive General Manager at OneFortyOne Ltd, Dana Clark – Team Leader Restoration Ecology at Cawthron Institute, Hugh Morrison – Chief Executive Officer at Port Nelson, and Volker Kuntzsch – Chief Executive Officer at Cawthron Institute.