The Greenwave Aotearoa team, Ryan Marchington of EnviroStrat (left), aquaculture operator Lucas Evans of Premium Seas, and University of Waikato's Peter Randrup. Photo / Alison Smith
The Greenwave Aotearoa team, Ryan Marchington of EnviroStrat (left), aquaculture operator Lucas Evans of Premium Seas, and University of Waikato's Peter Randrup. Photo / Alison Smith
The first commercial planting of a native red New Zealand seaweed has been achieved off Tīkapa Moana Hauraki Gulf in the Coromandel.
Fertile seedlings of Gigartina (Sarcothalia) atropurpurea have been grown on to twine attached around ropes in a seaweed growing trial site near mussel farms off the Coromandel coast.
The trial was permitted by Greenwave Aotearoa, a three-year regenerative ocean farming pilot, co-funded by the Ministry for Primary Industries Sustainable Food and Fibre Futures Fund and New Zealand-based end-to-end natural resource sector adviser, project developer and investor, EnviroStrat.
Greenwave Aotearoa project manager Rebecca Barclay-Cameron said the goal was to set up a New Zealand seaweed farming industry that allowed farmers to be small business owners.
“To do that, we are trying to establish an economically viable seed-to-sale seaweed industry.”
As Greenwave shared in its last update on the cultivation of Gigartina, it’s a slow tender process to get to the hatching stage.
“So reaching this milestone of being the first to get them out-planted is a really exciting moment for us,” Barclay-Cameron said.
Gigartina atropurpurea is a beautiful red seaweed with a leafy blade that grows in rock, cobbles and shell areas of sheltered sites through to open coasts.
It grows in the North Island, northern South Island and Chatham Islands.
Getting the species growing from seed stock sourced under permit in the Hauraki Gulf involved collaboration by staff from EnviroStrat as project initiators and managers, the University of Waikato assisting in research and Premium Seas providing the operations support.
Ryan Marchington, of Greenwave Aotearoa, prepares the first planting out of the native New Zealand seaweed Gigartina grown from a commercial hatchery. Photo / Alison Smith
All were on board for the release of the baby Gigartina seedlings into the ocean.
Peter Randrup, from the University of Waikato, said the seaweed provided opportunities for some sectors.
“This seaweed is rubbery so it’s got some quite interesting carrageenans and thickeners in it, which means it’s got some potential in food ingredients and cosmetics as well.”
Randrup said the seedlings looked promising so far.
University of Waikato's Peter Randrup (left) and Greenwave Aotearoa/EnviroStrat's Ryan Marchington in the Coromandel laboratory where different native seaweeds are being hatched. Photo / Alison Smith
“These guys are about two months old and growing at a reasonable pace for a seaweed and they’re looking really good.”
The seaweed growing industry is in its infancy in New Zealand and has a small but dedicated number of established businesses using native species for products, such as food ingredients and bio-stimulants for soil and animals.
Barclay-Cameron said seaweed was an “incredible species” and the regenerative ocean farming model used by Greenwave Aotearoa required zero inputs.
Gigartina on twine. Photo / Alison Smith
“You use seaweed as a foundation crop and then you can add a shellfish species like mussels or oysters, and when they grow they’re removing nitrates and phosphates from the water.
“Seaweed creates an environment for more species to come, shelter and grow so it actually increases fish populations as well.”
Seaweed source tissue was collected under permit in May this year and was dried (desiccated) and rehydrated in seawater in the small Greenwave Aotearoa commercial laboratory on the Coromandel.
Only a small amount is required for the process.
Stress-induced reproduction can be a natural response of plants to ensure their survival.
The desiccation process is used to stress the cells of the seaweed source material to release their spores.
EnviroStrat will support Greenwave Aotearoa to further drive the seaweed sector in New Zealand with training and support for seaweed farmers, and product innovations to create a value chain in coastal communities.
