Marine Microbes Must Anchor Europe’s Ocean Policy, Microbiology Society Urges

Marine microorganisms have long been the invisible engines of the ocean, quietly performing the chemical and biological work that keeps the seas, and indeed the planet, habitable. Now, one of the world’s leading microbiology societies is demanding that these microscopic powerhouses be given a central place in European ocean legislation. Applied Microbiology International, or AMI, has submitted a formal response to the European Commission’s consultation on the proposed EU Ocean Act, arguing that the health of the ocean cannot be understood, measured or protected without putting marine microbes at the very heart of policy. The response, prepared with input from members of the society’s Ocean Sustainability Advisory Group, draws on the expertise of international microbiologists working across the fields of marine ecology, biogeochemistry, genomics and applied biotechnology.

The submission took an unusual and deliberately democratic form. Rather than speaking with a single voice, AMI combined a survey reflecting the majority view of participating members with a detailed supporting document that sets out the scientific case for greater recognition of marine microorganisms in European ocean policy. The society’s central message is unambiguous: marine microbes must be explicitly recognised as fundamental components of ocean ecosystems, and their needs and contributions must be considered across biodiversity conservation, ecosystem management, ocean-climate policy and the assessment of overall marine health. In other words, an ocean act that only protects what can be seen with the naked eye is, in the view of these scientists, an act that protects only a fraction of what matters.

The scientific rationale for this position is compelling. Microorganisms, including phytoplankton, bacteria, archaea and viruses, drive many of the biological and chemical processes that regulate the ocean. They are responsible for recycling around half of global primary production, a staggering figure that underscores just how much of the planet’s carbon and nutrient throughput depends on organisms too small to see. Through the biological carbon pump, phytoplankton fix carbon dioxide at the surface and export it to the deep sea, while the microbial carbon pump converts dissolved organic matter into long-lived reservoirs that can keep carbon out of the atmosphere for centuries. Microbes also orchestrate the cycling of nitrogen, phosphorus and iron, elements that determine how productive marine food webs can be and how much carbon the ocean can ultimately sequester.

The urgency of this agenda is growing as the ocean changes. As marine waters warm, acidify and lose oxygen, microbial communities are being pushed into conditions they have not experienced on human timescales. Because microbes reproduce quickly and respond rapidly to shifting temperatures, pH levels and nutrient supplies, changes in their community composition and metabolic function often precede visible changes in larger organisms and habitats. Understanding how these communities respond to ocean warming, acidification and deoxygenation will therefore be increasingly important for predicting future shifts in ecosystem function, for anticipating how climate regulation services may weaken, and for designing interventions that support microbial processes capable of buffering environmental stress rather than amplifying it.

Beyond free-living microbes, AMI’s response draws attention to the intimate partnerships between microorganisms and larger marine life. Corals, sponges, seagrasses and fish all exist in close association with complex microbial communities that can influence nutrition, disease resistance and resilience to environmental stress. The coral microbiome, for example, can determine whether a reef survives a bleaching event, while the microbial partners of seagrasses are essential for nutrient uptake in the sediments that anchor these meadows. AMI argues that recognising these host-associated microbiomes could materially strengthen conservation and restoration efforts, by ensuring that the microscopic processes underpinning ecosystem health are not overlooked when protected areas are designated, when species are translocated, or when damaged habitats are actively restored.

There is also a powerful economic argument embedded in the society’s submission. Marine microbial communities represent a largely unexplored reservoir of genetic and biochemical diversity, a living library of molecules shaped by billions of years of evolution in some of the most extreme environments on Earth. Potential applications range from novel medicines and industrial enzymes to new biomaterials and biotechnological processes, with microbial enzymes from cold-adapted and pressure-tolerant species already finding uses in industry and research. AMI stresses that protecting marine microbial biodiversity is therefore not only an environmental priority but also an investment in future innovation, feeding directly into the ambitions of the European blue bioeconomy and the continent’s broader strategy for sustainable growth grounded in living resources.

Translating this science into law, AMI offers a series of concrete recommendations. First, the society calls for strengthening the definition and assessment of Good Environmental Status, the benchmark against which European seas are measured, so that it explicitly considers microbial diversity, community composition, functional diversity and the ecosystem services that microbes provide. Second, the submission urges that host-associated microbiomes be formally recognised wherever they are important to the health and resilience of protected species, habitats and ecosystems. These changes would mean that monitoring programmes, conservation targets and restoration criteria under the Ocean Act would no longer treat microbes as an afterthought but as measurable, reportable components of environmental quality in their own right.

The response also argues that an ecosystem-based approach to ocean management must move beyond a focus on visible organisms and iconic habitats. Microorganisms drive the processes that make marine ecosystems possible, including nutrient cycling, carbon sequestration, primary productivity and decomposition. Their rapid responses to environmental change could provide early-warning indicators of ecosystem condition and recovery, offering policymakers near-real-time signals of stress long before fish stocks decline or habitats collapse. Incorporating microbial indicators into routine monitoring would give regulators a finer-grained, more responsive picture of ocean health, and could reveal whether management measures are actually working at the functional level where the ocean’s essential chemistry is performed.

By bringing together the expertise and perspectives of its global membership, AMI is advocating for an Ocean Act that recognises the full biological complexity of marine ecosystems and puts microbiology firmly within Europe’s vision for a healthy, resilient and sustainable ocean. The society, the oldest microbiology society in the United Kingdom with more than half of its members based outside the country, publishes The Microbiologist magazine and three internationally recognised journals in partnership with Oxford University Press, and it frames this intervention as part of its wider mission to amplify the collective influence of applied microbiologists in evidence-based decision making. The consultation response makes clear that the microbes drifting in every litre of seawater are not a footnote to ocean policy; they are its scientific foundation, and the legislation that will govern European seas for decades should say so explicitly.

Subject of Research: The role of marine microorganisms in European ocean policy and the proposed EU Ocean Act

Article Title: AMI calls for marine microbes to be at the heart of Europe’s future ocean policy

Article References: AMI calls for marine microbes to be at the heart of Europe’s future ocean policy. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: marine microbes, EU Ocean Act, Applied Microbiology International, ocean policy, microbial carbon pump, Good Environmental Status, blue bioeconomy, host-associated microbiomes, ocean acidification, biodiversity conservation, ecosystem monitoring, phytoplankton