Six seaweed species could put NZ on the map

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Researchers have highlighted six species of rimurimu/seaweed which could form the backbone of our untapped blue economy. They range from the taonga species karengo, to green algae. The researchers say cultivating New Zealand's seaweeds could also help improve marine ecosystems, but there is still a lot of uncertainty around the possible negative effects of mass-scale seaweed farming.

Organisation/s: Sustainable Seas National Science Challenge

Funder: Sustainable Seas National Science Challenge

Media release

From: Sustainable Seas National Science Challenge

SIX RIMURIMU/SEAWEED SPECIES COULD PUT AOTEAROA NEW ZEALAND ON THE MAP

Rimurimu/seaweed should be a natural contributor to Aotearoa New Zealand’s blue economy because there is a wealth of diversity of rimurimu/seaweed species growing along our coastlines.

Although recent research shows our country could gain huge benefits, the seaweed sector is still in its infancy as New Zealand currently only harvests wild seaweed.

According to two new reports released by the Sustainable Seas National Science Challenge, developing aquaculture farms using an ecosystem-based management (EBM) approach and with
co-ordination between industry, iwi/hapū and regulators could grow Aotearoa New Zealand’s seaweed sector safely, significantly and effectively.

The Species characteristics and Te Tiriti o Waitangi considerations report, has reviewed six seaweed species groups identified for commercial development: karengo, Asparagopsis, agarophytes, lamanarians, fucoids and green algae.

“Our species are generally underdeveloped in regard to their commercial potential and there is an opportunity to produce and sell seaweed products that are different from those in other parts of the world,” explains Serean Adams, project leader of Building a seaweed sector.

But targeting high-value markets requires specific information on each species. “Current knowledge of seaweed species is mostly focused on their ecology. Information about the biology and how to cultivate the species is sparse and scattered through scientific literature. This makes it difficult for those interested in developing a seaweed sector to access.”

That’s why the research suggests one approach may be to build from our already existing bio stimulant and fertiliser market. These markets could then be used as a platform to move into higher value products. For example, extracts as functional foods, food ingredients and health supplements or cosmeceuticals.

The report helps highlight the cultural importance of seaweed species to Māori and to support the role of Māori kaitiaki rights in the emerging seaweed sector.

“Māori have a particularly unique whakapapa relationship with flora and fauna and we need to acknowledge and respect that in the process of developing this sector,” says Andy Elliot, Research and Business Development Manager from Wakatū Incorporation, a whānau-owned organisation involved in seaweed research. “For example, karengo is considered a taonga.”

Practical experience in growing, processing and marketing seaweeds and seaweed products in Aotearoa New Zealand is limited. This could be an opportunity for iwi/hapū to be supported to create sustainable seaweed businesses founded on their vision and values.

The other report, Environmental effects of seaweed wild-harvest and aquaculture, recognises why an EBM framework is vital. There may also be potential for seaweed farming to improve ecosystems because seaweed can help with nutrient removal, shoreline protection, regenerative opportunities, and offers the potential for carbon sequestration.

However, this report shows that many of the benefits (and risks) are site and scale specific, and there is associated uncertainty as a result.

“No matter what species are chosen, the development of commercially-viable farming systems is probably the most pressing hurdle to overcome,” explains Dr Adams. “This can be best achieved through leveraging overseas expertise, and by ensuring that knowledge generated through Aotearoa New Zealand research is publicly accessible. This enables farmers to ‘give it a go’ using approaches that are appropriate for the Aotearoa New Zealand situation.”

The time is right for Aotearoa New Zealand to take advantage of this growing industry and expand our budding seaweed sector by using the suitability of our environment for seaweed aquaculture.

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Multimedia:

  • Map showing areas ecologically suitable for seaweed aquaculture
    Map showing areas ecologically suitable for seaweed aquaculture

    FIGURE Map showing areas ecologically suitable for seaweed aquaculture CREDIT adapted by Revell Design for the Sustainable Seas Challenge with permission from Froelich et al (2019)

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    Attribution: Adapted by Revell Design with permission from Froelich et al (2019)

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  • Carbon cycle within seaweed farms
    Carbon cycle within seaweed farms

    INFOGRAPHIC - Carbon cycle within seaweed farms CREDIT Sustainable Seas Challenge, Revell Design

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  • Possible ecosystem services and negative environmental effects
    Possible ecosystem services and negative environmental effects

    INFOGRAPHIC - Possible ecosystem services and negative environmental effects associated with seaweed aquaculture in coastal environments CREDIT Sustainable Seas Challenge, Revell Design

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  • Carpophilum spp, Macrocystis pyrifera, Landsburgia spp, Ecklonia radiata
    Carpophilum spp, Macrocystis pyrifera, Landsburgia spp, Ecklonia radiata

    Kaikoura - Carpophilum spp, Macrocystis pyrifera, Landsburgia spp, Ecklonia radiata CREDIT NIWA, Leigh Tait

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    Attribution: NIWA, Leigh Tait

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  • Floating Macrocystis pyrifera
    Floating Macrocystis pyrifera

    Kaikoura - floating Macrocystis pyrifera CREDIT NIWA, Leigh Tait

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    Attribution: NIWA, Leigh Tait

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