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A new study examining integrated multi-trophic aquaculture (IMTA) in Bantry Bay, Ireland, has found direct nutrient transfer from farmed salmon to cultivated kelp, demonstrating measurable ecological connectivity between the two species.

The research focused on a system in which a kelp farm was positioned approximately 200 meters from a salmon farm that resumed production in mid-2023 after a four-year hiatus. Scientists investigated whether dissolved nutrients released from salmon operations could be transported by marine currents and subsequently absorbed by kelp grown nearby.

To assess this interaction, researchers used a hydrodynamic model known as the Regional Ocean Modeling System (ROMS). The model simulated how nitrogen released from salmon cages dispersed throughout Bantry Bay, accounting for water movement and temperature conditions. Results showed that marine currents transported nutrients from the salmon site directly to the kelp cultivation area.

The Bantry Bay kelp site consists of 17 cultivation lines, each measuring 110 meters, and is designed for high biomass production. The study evaluated nutrient dynamics alongside broader environmental indicators, including biodiversity, carbon dioxide sequestration potential, and the system’s capacity to buffer ocean acidification.

Findings confirmed that nitrogen originating from salmon farming activities was taken up by the adjacent kelp crop. This direct nutrient transfer supports the principles of IMTA, in which waste outputs from one species become resource inputs for another. In this case, dissolved nutrients released by salmon provided a growth input for kelp.

The researchers highlighted that such integrated systems may enhance overall environmental performance by recycling nutrients within the marine environment. In addition to nutrient uptake, the demonstration project explored the potential for kelp cultivation to contribute to biodiversity improvements and carbon capture while operating alongside finfish aquaculture.

The Bantry Bay trial provides modeled and site-based evidence that spatially coordinated salmon and seaweed farming can function as a connected biological system. By confirming nutrient transfer across a 200-meter distance, the study offers data-driven insight into how IMTA designs may be optimized in open-water conditions.

Regenerative sea farming in Wales has been given a significant boost following approval to expand operations after a breakthrough in kelp-derived biostimulants. Câr-y-Môr, the community-owned seaweed and shellfish farming business based in Pembrokeshire, has received the green light to extend its marine licence, allowing it to increase the size of its sea farms.

The expansion will see the company’s total farmed area grow to eight hectares. This includes two hectares at Carn ar Wig and three hectares at Porthlysgi, which will join the existing three-hectare site at St Justinian’s. The approval coincides with the opening of Câr-y-Môr’s new Sied-y-Môr facility, located a few miles inland. The site is home to Wales’ first dedicated seaweed biorefinery and represents a key milestone in the organisation’s development.

The expansion follows progress in the development of kelp-derived biostimulants, which are natural substances used to enhance plant growth and resilience. The innovation is seen as having major potential to support sustainable intensification in agriculture, particularly as the sector adapts to climate change. By processing locally grown seaweed into high-value agricultural inputs, the business aims to create new revenue streams while supporting environmentally sustainable practices.

Regenerative sea farming is promoted as a restorative approach that requires no fresh water, fertiliser, feed or land. It is also recognised for its ability to sequester carbon and nitrogen, provide storm surge protection, rebuild marine ecosystems and supply organic produce. Supporters argue that the model can deliver environmental, social and economic benefits simultaneously.

The vision for regenerative sea farming in Wales has been described as highly achievable, with relatively low barriers to entry for new operators. With appropriate consents, access to a small area of sea, a vessel and initial capital investment, new farms could be established within a year. Proponents believe the sector has the potential to make a substantial contribution to coastal communities, supporting job creation and strengthening the local economy.

The latest licence approval and biostimulant breakthrough mark an important step forward in positioning Wales as a leader in regenerative ocean farming and sustainable marine innovation.

Researchers from The University of Adelaide have demonstrated that a naturally derived compound from seaweed can significantly reduce methane emissions in beef cattle raised in extensive grazing systems. The findings show methane reductions of up to 77 per cent without harming calves, marking a notable step forward in efforts to curb livestock-related greenhouse gas emissions.

The study focused on supplementing cattle diets with a seaweed-derived compound under real-world grazing conditions. Unlike previous controlled feedlot trials, this research evaluated the additive in extensive systems more representative of commercial beef production. The results confirmed substantial methane reductions, even when the compound was administered at slightly lower concentrations than in earlier experiments that achieved higher emissions cuts.

Importantly, researchers found no adverse effects on calves, addressing concerns about potential impacts on animal health and development. The study contributes to a growing body of evidence supporting seaweed-based feed additives as a viable methane mitigation strategy for the beef industry.

However, the trial also identified areas requiring further investigation. Animals receiving the supplement consumed less feed and experienced slower weight gain compared to those not given the additive. Researchers noted that the reasons for reduced feed intake and slower growth remain unclear and warrant additional study to optimise dosage and ensure productivity is maintained.

Methane produced by cattle is a significant contributor to agricultural greenhouse gas emissions. As global attention intensifies on climate change mitigation, practical solutions for reducing emissions in large-scale grazing systems are increasingly important. The University of Adelaide team’s findings suggest that seaweed-derived compounds could offer a scalable option for lowering methane output in beef production, provided that performance impacts are better understood and managed.

The research adds to ongoing efforts to balance environmental sustainability with the economic viability of livestock operations, highlighting both the promise and the practical considerations of adopting methane-reducing feed technologies in commercial beef systems.

Founded in the Netherlands, Zeefier is an innovative company developing textile dyes made from seaweed. By replacing petrol‑based chemistry with a renewable ocean resource, Zeefier offers an alternative that enables textiles to remain biodegradable. Zeefier is expanding its solution for dye houses worldwide with help from the EU's BlueInvest program.

For the second year in a row, a coalition of mariculture interests has hired the McKinley Research Group and the Pacific Shellfish Institute to compile data and research about the state of Alaska’s mariculture industry.

The 45-day comment period is open through May 28, 2026. We will also host two public scoping meetings to gather input.

The Alaska Fisheries Development Foundation (AFDF), a Juneau, Alaska, U.S.A.-based nonprofit, announced it will sponsor a new round of research and development projects with funding from the Alaska Mariculture Cluster (AMC).