Research Program
PROJECT LEADER
PROJECT ID
2.21.005
BECRC PARTNERS
BMT
Climate Foundation
CSIRO
Huon Aquaculture
Southern Ocean Carbon Company
State Government of Tasmania
University of Queensland
UTAS
THIRD PARTY PARTICIPANTS
Deloitte Australia
START DATE
November 2022
END DATE
October 2024
DURATION
24 months
PROJECT IN BRIEF
The global seaweed market is valued currently at >US$6B annually and is growing rapidly, however in Australia the seaweed industry and associated product development is nascent. Several independent analyses have identified considerable opportunities for Australia in building a modern and sophisticated industry based on seaweed production at commercial scale and developing seaweed-based bioproducts.
This project seeks to develop technologies suitable for commercial scale offshore kelp production off southeast Tasmania in particular, but which could also be deployed in offshore environments elsewhere in Australia and New Zealand.
The project will review, design and trial offshore production systems for kelp mariculture, further select for kelp genotypes to cope with ocean warming, assess the performance and potential impact of the kelp production system, and use these empirical measures to model production, environmental impacts (positive and negative) and economic viability of kelp mariculture at commercial scales.
In parallel, we will review, assess and recommend changes to policy and regulatory frameworks to ensure unambiguous guidelines to achieve industry sustainability, environmental safeguards, and social licence. Project design reflects that industry development will require careful integration and coherence across all of these elements.
The overall goal is to develop, test and demonstrate technologies for offshore kelp mariculture that:
- are scalable,
- are economically viable,
- achieve positive environmental outcomes,
- attract strong social licence,
- and are supported by appropriate policy and regulatory frameworks.
Project Phases
The research project is designed in two phases. Phase I will focus on:
- engineering design, including modelling and testing of scale models (using facilities at AMC),
- in-water testing of a modular mariculture unit at a relatively sheltered site,
- extensive monitoring of the in-water trial,
- modelling to inform site selection for Phase II,
- analysis and development of a policy and regulatory framework to underpin seaweed mariculture in Tasmania,
- and economic analyses comprising an economic viability assessment and natural capital accounting evalution.
Phase II is not yet funded since whether it is sensible to proceed with Phase II depends heavily on the results from Phase I.
FREQUENTLY ASKED QUESTIONS
- A permit has been issued by the Department of Natural Resources and Environment Tasmania for deployment of in-water apparatus to conduct research on growing kelp at a site south of Blackmans Bay and north of the Tinderbox Reserve (please see map on point 2).
- The proposed site is in the Tinderbox region south of the Blackmans Bay Wastewater Treatment facility with special markers moved to the coordinates shown below and will remain in place for the duration of the project.
This proposed site has been selected following analysis of ocean characteristics in the region. There are two compelling reasons for selection of the site:
- It supports elevated nutrient levels associated with the Blackmans Bay Waste Treatment facility conducive to kelp growth and survival.
- This location is moderately exposed. Thus, while it is not subject to the rigours of offshore sites, it is open to sufficient swell for researchers to measure loads on the apparatus as a function of sea conditions and kelp growth.
- The corners of the area will be marked for navigation purposes in accordance with advice from MAST (Marine and Safety Tasmania) to show the area within which the infrastructure (aquaculture rings, underwater array of grow lines, and anchoring system) is deployed.
- While we have not sought to have access by vessels prohibited, in accordance with the State Government’s decision, mariners are advised that all vessels not directly involved in Scientific Research activities associated with the Kelp Research area are prohibited from entering inside the marked area while the research permit is in place. View the Notice to Mariners.
- The in-water research trial will use modified aquaculture rings for growing kelp.
- The research trial will use rings that do NOT support nets above or below water. Each ring will consist only of the floating ring and its anchors, and kelp will be grown on lines suspended from the rings. Rings have a handrail for safety. They will be anchored over sand in ~15 m water and the kelp grow lines will run parallel to the water surface at a depth of ~5 or 10 m. The role of the rings is purely to support the kelp lines, and no fish will be grown in the structures.
- The infrastructure deployed will include three small rings (18 m diam) and associated moorings. The large 54 m diam surface ring considered previously has now been replaced by an underwater array consisting of 60 m long grow lines at a depth of ~10 m.
- The rings will largely support giant kelp (Macrocystis pyrifera) grown on lines parallel to the water surface, which run from one side of the ring to the other.
- Wakame (Undaria pinnatifida) will also be grown on one of the small rings.
- Both species currently occur on the low-profile coastal reef adjacent to the proposed deployment site.
- Undaria will be harvested before it becomes reproductive. While this seaweed already grows along this coastline, it is not an endemic species. Harvesting in this way will prevent further Undaria growth in the area outside of the rings, both during and after the trial.
- This design will enable the project to test different kelp cultivars (i.e. different family lines), different grow-out and harvest strategies, and different types of grow-out lines.
Weather permitting, anchors will be deployed mid-June with out-planting of microsporophytes (baby kelp) immediately following.
- This infrastructure will be deployed in water for ~18 months to enable developing and testing systems for kelp deployment, monitoring and harvesting.
- This is a research trial designed to test seaweed species for potential off-shore (deep ocean) farming. Once the trial is completed all apparatus will be removed from the site. There is no intention to continue project activity in the area beyond this trial.
- The project team is rolling out a comprehensive stakeholder and community consultation process.
- This includes initiating contact with the local Aboriginal community groups and a range of key interest groups and stakeholders through one-on-one briefings, open community sessions, briefings to stakeholder groups and associations, and through social media.
- We will consider recommendations put to the project team, noting that essential requirements of the site for deployment of the rings include limited (i.e. moderate) exposure and elevated nitrate levels, which limits location options for the trial.
- We acknowledge that maritime navigation and safety are critical considerations in our research site placement, and that understanding and avoiding maritime navigational corridors in different weather conditions is critical for safety at sea.
- Amenity and viewscapes are also important considerations for consultation. We emphasise that the rings are low profile, i.e. they have a much smaller profile than the typical polar circle pens used for a finfish operation.
- Noise of operations and light pollution are other important considerations. The research operation does not have the same vessel transit frequency, or agri-husbandry needs, or infrastructure set up as a finfish operation. There are no platforms supporting the rings, no engines are required on the apparatus, and the only lighting will be any required navigational markers.
- Once the deployment is completed, 2-3 crews will visit the site in small aluminium vessels (~8 m length) on average every 3 months to make various measurements in monitoring. Each monitoring visit may take several days to complete.
No. This is a Research Project is funded by the Blue Economy CRC and the nine Project Partners: BMT, Climate Foundation, CSIRO, Huon Aquaculture, Southern Ocean Carbon Company, Tasmanian Government, University of Queensland, Deloitte, and UTAS (IMAS and the Australian Maritime College).
- We will develop and lodge with the Tasmanian Government a gear register and also mark the floating gear used for the trial. We do not anticipate any marine debris but we will be fully responsible for retrieving any debris, should it occur.
- We know that an alternative source of nitrogen to underpin high production rates of kelp is ammonia released from finfish farms.
- Recent work by the IMAS team has shown that kelp grown alongside finfish pens can achieve >800% improvements in production over identical genotypes grown nearby without an augmented nutrient source but otherwise under identical conditions.
- The project will continue to assess growing kelp alongside finfish aquaculture activities.
- We will assess the economic feasibility of growing kelps alongside finfish pens that provide a ready source of nutrient.
- This research will demonstrate the economic viability or non-viability of this approach for cultivating seaweed.
- While there is broad interest in growing kelp offshore at commercial scale in SE Australia, and some specific interest in the possibility of growing kelp in association with finfish pens, there is a gap in engineering and farm-process solutions to (i) provide appropriate and cost-effective mariculture infrastructure and systems, and (ii) in the absence of fish pens, to solve the issue of sufficient nutrient supply to ensure high production rates in an environmentally sustainable manner.
- The main beneficiaries of the output of Phase I will be the industry partners and diverse scientific team engaged on the project. We further anticipate that the results will be studied carefully by a much wider audience including other participants in the Blue Economy CRC and others interested in seaweed production offshore.
- The development of a scalable natural capital valuation model based on the data obtained through this project will translate to many other environmentally focussed projects around Australia (e.g. spanning habitat restoration, blue carbon, biodiversity improvement, and climate mitigation), facilitating ongoing investment in this kind of activity for social, economic, and environmental benefit.
- There are opportunities for students to be involved in the research.
- For example, students may be involved in analysis of the role of kelp epiphytic microbiome in nitrogen dynamics.
- It is intended that a masters or honours level student may be recruited to the zooplankton monitoring depending on initial results, and/or to monitoring of kelps on reefs adjacent to the in-water apparatus and monitoring of seabirds, mammals, and fishes.
- An existing BECRC PhD student will work on aspects of economic assessment and engineering design in Phase I of this project.
Project Updates
November 2024 Progress Update – Successful Giant Kelp harvest
This week the project team successfully harvested 3.6 tonnes of Macrocystis from the Tinderbox kelp lease. This major phase 1 project milestone comes just 6 months after the initial outplating of microscopic kelp on 18m diameter rings and 60m growlines to review, design and trial offshore production systems for kelp mariculture and test the viability of kelp mariculture at commercial scales. The team harvested 48m out of a total of 360m grow line with the average plant size ranging from 1.6m to a maximum length of 3.4m in just 6 months.
As project lead, Professor Jeff Wright states,
“The growth achieved after only 6 months at the Tinderbox site is impressive and it is likely production will be higher at other sites. We now have routine optimised hatchery and grow-out methods for Macrocystis which provides great opportunities for growing Macrocystis in other projects and contexts such as in deeper offshore environments.”
June 2024 Progress Update
Hatchery processes are well worked out and techniques are readily scalable for commercial purposes. Wakame has proven to be a model kelp species for mariculture. It is relatively easy to maintain in culture, fertilise, out-plant and grow in the ocean. In some areas it can grow rapidly without added nutrient.
Growth of giant kelp is very sensitive to light levels and temperature. In inshore waters where turbidity is higher, it is necessary to ‘out-plant’ at shallow depths (3-4 m) and lower grow lines to greater depths as the kelp develops. Out-planting at 8-9 m in a ‘set and forget’ process may be satisfactory for offshore sites. Waters affected by surface tannin layers are unsuitable for growing giant kelp due to reduced light levels.
The 2023-24 summer heatwave (water temperatures rose to 20-21 deg C) killed all out-planted giant kelp at the Tinderbox and Tower Bay sites. The same family lines, planted at the same time, showed much better survivorship at the Huon Aquaculture lease in Storm Bay despite that temperatures reached these same levels and that seed lines were deployed at 10-12 m. Consistent with results elsewhere, this shows clearly that the negative impacts of warming can be offset to some extent by providing higher levels of nitrogen, i.e. avoiding nutrient stress.
Limiting mariculture of giant kelp to 8-9 months each year to avoid the warm summer period may be the most sensible approach until selective breeding can identify cultivars that are more tolerant of warm water. This approach should still realise high biomass yield providing nutrient concentrations are adequate. It is clear that giant kelp mariculture in SE Australian waters will require an enhanced nutrient environment.
It is clear that mariculture of giant kelp will require a means to enhance nutrient (nitrogen) availability. Two approaches are being considered to access nitrogen in deeper waters. Depth-cycling is when the kelp are dropped to depth at night to uptake the nitrogen available in deeper waters, and then brought back to the surface at dawn to photosynthesise during the day. A prototype depth-cycling system has been developed by one of the project partners and trialled successfully in the Philippines. Further engineering development is required before this system is ready for trials in Tasmania. The second approach is to pump the relatively nitrogen rich water from depth to the kelp growing at the surface.
A major element of the project has been to examine the regulatory framework and policy settings in Tasmania in the context of seaweed mariculture. It is clear that the current legislative framework in Tasmania is appropriate for seaweed mariculture, however the project will make a number of recommendations to strengthen policy and ensure a rigorous science-based process for industry development.
June 2023 Progress Update
Microscopic kelp planting – how does it work?
Kelp Mariculture project – infrastructure deployment and baby kelp planting
Phase II – Planting of baby kelp
Phase I – Infrastructure Deployment
This month will be initiating next steps with the deployment of the required infrastructure followed by the planting of baby kelp this week in the research zone in Tinderbox.
Project infrastructure includes three small rings (18m diam) and associated moorings plus an underwater array consisting of 60m long grow lines at a depth of ~10m.
The corners of the area will be marked for navigation purposes in accordance with advice from Marine and Safety Tasmania and clearly visible signage will be installed on the infrastructure.
The planting of microsporophytes (baby kelp) will follow this coming weekend.
The project team will capture onsite footage and interviews throughout deployment which will be shared on the project page and our social networks.
2023 PARTICIPANTS WORKSHOP PROJECT UPDATE
May 2023 Progress Update
Under the Living Marine Resources Management Act 1995, Section 14: Scientific Research Permit, this project has been granted a permit for the purpose of scientific research to
- develop, test and demonstrate a production system for offshore marine plant mariculture; and
- deploy both submerged and floating marine farming longline equipment and supporting infrastructure, within a designated Permit Area, for the purpose of trialling the cultivation of out-planted Macrocystis pyrifera (giant kelp) and Undaria pinnatifida (wakame) sporophytes onto rope grow-lines to assess the potential for scalable offshore mariculture in Tasmania.
The final design of infrastructure to be deployed at the Tinderbox site differs to that proposed initially in that the large 54 m diameter floating ring will not be used, and instead will be replaced by a subsurface array of grow-lines at a depth of ~10 m.
March 2023 Progress Update
As of the end of March 2023, the completed permit application has now been submitted, following a draft permit application submitted to DNRET for feedback in October 2022 and communication and consultation with a diverse range of stakeholders, including: the Dept Natural Resources and Environment Tasmania, Tas Parks and Wildlife, Kingborough Council, Blackmans Bay Community Association, Residents of Tinderbox and Blackmans Bay, Kingston Beach Sailing Club, ABC morning radio 936 Tasmania, Marine and Safety Tasmania, Tasmanian Seafood Industry Council, TARFish, Tasmanian Aboriginal Centre and a presentation on the project was given at the International Seaweed Symposium.
The hatchery system is now fully operational, and cultures and spools have been prepared ready for culturing of microsporophytes on seed lines. This will commence only once the permit is awarded, and once it is known when the in-water grow lines will be ready to receive the seed strings.
New appointments to the project team include Dr Victor Shelamoff and Eva Smid to the hatchery / monitoring effort based at IMAS, and Dr Eric Gubesch to the engineering team at AMC.
Project lead Prof Craig Johnson states, “I’m pleased to see that in this early planning phase there has been strong communication and interaction across the engineering, bio- and physico-chemical monitoring, and economic assessment teams, facilitated in part by regular meetings of theme leaders. The project has now been outlined to a broad range of stakeholders, and interest in the research has been strong, with encouraging positive feedback”.
