The Role of Seaweed in NZ’s National Aquaculture Strategy
In September of this year, Aotearoa’s Minister of Fisheries, Hon Stuart Nash, announced the publication of New Zealand Government Aquaculture Strategy while attending the NZ Aquaculture Conference in Blenheim. This document lays out a strategic vision for growing the aquaculture sector in NZ five-fold, from its current revenues of $600M, up to $3B by 2035.
At the same time, there is a strong focus on environmental sustainability, and the need for a growing (and export-led) aquaculture sector to align with and represent Brand New Zealand – sustainable, healthy, and high-value.
This is certainly an ambitious and significant vision, and will have far reaching impacts across the sector and wider society.
But what does it mean for the prospects of macroalgae / seaweeds to be a significant contributor to the economic and environmental goals?
The answer is not explicit in this Strategy document, although some hints are given. Seaweeds are mentioned for their potential impact towards these sustainability outcomes:
their ability to buffer ocean acidification,
to provide ecosystem services and
to store carbon.
It’s also acknowledged that the objective of a higher-value, productive sector may be reached in part through tapping into algae as a source of “super-food”. Aside from these short mentions, the interested reader will need to dig deeper into a “nesting doll” of background materials that inform this aquaculture strategy to clarify how seaweed might play a role in the future of NZ’s aquaculture sector.
National Environmental Strategy
Like most documents of this type, the Aquaculture Strategy is long on goals, objectives and vision, yet short on details of concrete actions that will be needed to achieve those goals. That’s not a criticism - it’s simply the nature of developing and communicating strategy. However, just a couple of months before the release of this strategy, the government also revealed details for the preparation of a National Environmental Standard: Marine Aquaculture (NES), which although not yet complete, will be a key instrument by which the Strategy will be put into action in the short term.
The middle-doll in the nesting set, the NES, is a product of a process begun in 2017 under the last government and that included an open public consultation through 2017-18.
A significant aim of this process has been to address a coming wave of marine farm consent renewals. Over half of NZ’s 1200+ aquaculture operations have permits that will expire by the beginning of 2025, the end of their 20-year term that began with modifications to the Resource Management Act in 2004. To drive certainty and consistency across the industry the NES seeks to establish a nation-wide, standardized approach to permit renewals.
Among such proposed modifications as allowing species changes, and nationally consistent requirements for biosecurity management, the NES will require best-practice environmental assessments to be applied when considering replacement consent applications. These assessments will be at the discretion of the consenting regional council, and will be informed by a previously compiled, thorough review of the environmental impacts of aquaculture, performed by NIWA and the Cawthron Institute in 2013
“…aquaculture will lead in environmental practices across the value chain; be strong and protected from external risks of pests, disease and climate change; and work in collaboration with Māori and communities to realise meaningful jobs, wellbeing and prosperity.”
- Hon Stuart Nash, Minister of Fisheries
Image by Photo by Cameron Raynes via FreeImages
Ecological Effects of Aquaculture
And within this literature review, the innermost nesting doll, we finally find the most direct clues as to the government’s view of role of seaweed in NZ’s Aquaculture Strategy. In examining the ecological impacts of fin-fish and shellfish aquaculture, the potentially synergistic and beneficial role of “lower-trophic level” species such as sea-cucumbers and seaweed is highlighted. Marine farmers are encouraged to consider Integrated Multi-trophic Aquaculture (IMTA) to manage ecological effects of their practices, especially in regard to dissolved nutrient wastes from farmed finfish, and the natural ability of seaweed to absorb those potential pollutants out of the water column. Seaweed are clearly seen as potential mitigators of aquaculture impacts.
The ecological impacts of farming seaweed itself are also discussed in this literature review, and noted to be of much lower concern than those from finfish or shellfish. Due to a lack of practical experience, there are open questions on possible negative interactions with marine mammals and sea birds, through entanglement, habitat modifications etc. Nutrient depletion is another potential risk noted, in situations where seaweed farms are scaled too large for natural water flushing to be able to replenish nutrients. Notably also, biosecurity concerns were highlighted around the cultivation of Undaria, a non-native invasive species that is, ironically, the only seaweed discussed in detail as a cultivation target.
What does this mean for seaweed aquaculture in Aotearoa?
Although the Aquaculture Strategy barely mentions seaweed, it is clear that co-culturing macro-algae with established aquaculture species in an IMTA-approach is one of the most important ways that incumbent operators can improve the ecological impacts of their operations. With over 600 consent renewals due to be submitted in the next four years under the new NES, operators are going to have to demonstrate to their regional councils that they are across the best practices and innovations needed for aquaculture in Aotearoa to live up to the Brand New Zealand aspiration articulated in the Government’s Aquaculture Strategy. If even only a fraction of these renewals include seaweed as a tool for diversification and remediation, it’s clear that this new regulatory framework could be a significant driver of scale for seaweed aquaculture in Aotearoa.
Business as unusual
The Aquaculture Strategy and NES articulate a vision and tool-set that is firmly based on business as usual. The current “big three” products of salmon, oysters and mussels dominate the discussion and future vision. Yes, there is room for improvement and development of these three product lines (i.e. new cultivation systems, selective breeding, higher-value extracts and products etc), but very little is put forward in the way of diversification out of the big three by introducing novel species and a broader range of products and services that could be derived from them.
The biggest lack of vision or imagination in these government documents is to imply that seaweed’s main utility is only in cleaning up the mess of other species being farmed, and even then only by growing a non-native invasive species. There are numerous species of native macro-algae with demonstrated utility and value, and a growing tool-set of downstream applications and markets to which farmed seaweed could be directed. A critical mass of researchers, entrepreneurs, and investors are already moving forward on building an alga-culture sector in New Zealand, even if the Government’s Aquaculture Strategy only tangentially acknowledges that potential.
The good thing is that the government intends to publish an annual implementation plan that will lay out the key actions to be taken each year by relevant agencies. As seaweed in NZ moves from strength to strength, these annual plans will provide an opportunity to adjust the strategic priorities going forward to reflect the true potential of seaweed to be a key component of
an ecologically and socially regenerative
aquaculture industry in Aotearoa.