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First kelp seedlings planted out in NZ ocean farming pilot

Updated: Dec 20, 2022

The GreenwaveNZ pilot has planted out its first hatchery raised Ecklonia radiata seedlings. Photo: Photo Scott Sinton

Golden kelp, native to Australia and New Zealand, is the focus of ocean trials being undertaken by GreenWaveNZ.

Hatchery-reared seedlings of Ecklonia radiata, also known as golden kelp or common kelp in Australia, have been planted out to sea off New Zealand's North Island, marking an important milestone in its regenerative ocean farming pilot project.

The 3-year pilot is led by natural resource sector project developer EnviroStrat, which has been collaborating with US-based GreenWave since 2019 to adapt its successful regenerative ocean farming model for New Zealand.

GreenWaveNZ has received $5 million in funding for the pilot, including $2 million from the New Zealand Ministry for Primary Industries. EnviroStrat, impact investors and local philanthropists have contributed an additional $3 million to help pave the way for a sustainable seaweed aquaculture industry in New Zealand.

Collaborating partners include Māori iwis Ngāti Pūkenga and Ngāi Tai ki Tāmaki, seaweed product developer Premium Seas, the Universities of Waikato and Auckland and seaweed processor AgriSea.

The pilot is focused on creating an economically viable seed-to-harvest model for seaweed farming in New Zealand, as well as establishing a sustainable, functioning supply chain, opening up new opportunities to tap into the US$14 billion global seaweed market.

Propagation and farming of Ecklonia radiata are also being investigated in Australia, with research in the NSW, South Australia, Tasmania and Victoria.

EnviroStrat CEO Dr Nigel Bradly says the outplanting of hatchery-grown seaweed is a significant step for the project. It will provide essential information to underpin the commercial realities of seaweed productivity in New Zealand.

The pilot is taking place on three existing consented aquaculture farm sites in the Hauraki Gulf, supported by hatcheries in the Coromandel and Bay of Plenty. Two of the farm sites are actively farming mussels; the third has been approved for mussels but is not yet actively growing them. A fourth site to grow out the seaweed is also being considered.

There is significant interest in seaweed farming from New Zealand mussel and oyster farmers who are keen to adopt practical ways to diversify their farming operations.

Bradly says growing seaweeds and shellfish such as oysters and mussels together creates regenerative ocean farming systems, while leveraging existing skills and aquaculture experience for positive social and environmental impact while enabling profitable business.

But while there is a lot of seaweed farming knowledge to draw from internationally, he says there is no experience or understanding of how to farm New Zealand’s local species.

“The contribution of the wider team’s skills and expertise enables us to blend operational, science and commercial experience, to ensure that commercial seaweed farming will be a part of New Zealand’s blue economy future.”

GreenWave co-founder and co-executive director Bren Smith says it is exciting to see more than three years of thoughtful planning and partnership development in New Zealand shift into action.

"In addition to advancing the economic and environmental goals of coastal communities in New Zealand, bringing these lessons back to the broader ocean farming industry will be a catalyst for communities around the globe searching for solutions to make a living on a living planet,” Smith says.

Seaweed pilot partners

Working with iwi is at the heart of the pilot. Ngāti Pūkenga and Ngāi Tai ki Tāmaki are providing consented water space in the Hauraki Gulf.

Lucas Evans, CEO of Premium Seas, is facilitating access to water space, managing the Coromandel hatchery and providing oversight for the farming operations while gaining efficiencies along the way.

University of Waikato researchers Dr Marie Magnusson and Dr Rebecca Lawton are overseeing the research and trial design. Professor Andrew Jeffs at the University of Auckland is leading monitoring to establish the biodiversity impacts of co-locating mussels and seaweed farming.

Scientists from the University of Waikato collected local wild Ecklonia material from rocky reefs near the pilot sites. The reproductive tissue was cut, cleaned and processed to release microscopic spores.

The spores, contained in a concentrated solution at a hatchery at the university’s Tauranga campus were then added to aquaria containing spools of seed string and grown for 40-60 days to become seedlings. These seed strings are de-spooled onto grow ropes and outplanted from a barge.

AgriSea is contributing its post-harvest processing, production and market expertise, and it will purchase the biomass produced for use in its existing product range of biostimulants, bee nutrition, animal health supplements and hydrogels.

The pilot project will conclude in 2024 and, if successful, Bradly says the next step will be to scale up production trials to other parts of New Zealand to increase the footprint of seaweed farming.

A barge was used to put out seaweed seedlings onto mussel farms off New Zealand's North Island. Photo Scott Sinton

More information: Envirosrat, New Zealand

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