Falmouth Seagrass: Restoring Cornwall’s Hidden Underwater Meadows

When most people think of underwater life, they picture colourful corals, darting fish, or dramatic kelp forests. Rarely does seagrass come to mind. Yet these hidden meadows, waving gently beneath the waves, are among the most important ecosystems on Earth, and right here in Cornwall, big plans are underway to restore them.

Seagrass is often called the “meadows of the oceans” or the “rainforest of the sea” because it supports biodiversity, absorbs carbon, and protects coastlines. But unlike tropical rainforests, seagrass meadows are almost invisible to the public eye, unless you go under seawater. Many people in Cornwall walk the beaches of the Fal and Helford estuaries without realising that just offshore lies a world of flowering plants, struggling quietly against anthropogenic/human pressures and climate change.

This blog dives into what seagrass is, why it matters, and how the Falmouth Seagrass Restoration Project aims to bring back life to degraded areas. It also looks at international lessons, especially from places like Seychelles, and what we can all do to support these efforts, whether as divers, students, or everyday beachgoers.

What is Seagrass? (And Why It Isn’t Just Seaweed)

Seagrasses are not algae. They are true flowering plants (angiosperms), more closely related to lilies than to kelp. Their scientific name in Cornwall is Zostera marina (commonly called common eelgrass). Unlike seaweeds, they have roots, rhizomes, and leaves. These roots anchor them into sandy or muddy substrates, while their rhizomes spread horizontally underground, allowing seagrass to form dense, interconnected meadows (Orth et al., 2006).

Globally, there are around 72 seagrass species across temperate and tropical waters (Green & Short, 2003). In the UK, the main species are Zostera marina (deep-water eelgrass) and Zostera noltii (dwarf eelgrass, found in intertidal zones). Other species include Posidonia oceanica in the Mediterranean, Thalassia testudinum in the Caribbean, and Thalassodendron ciliatum in the Indian Ocean (including Seychelles). Despite these differences, all seagrass species share vital ecosystem roles.

Comparative Taxonomy of Key Seagrass Species – link

Seagrass in the Ecosystem: Nurseries of the Sea

Seagrass meadows are biodiversity hotspots. They provide nursery grounds for fish, including commercial species like cod and pollack, and habitats for seahorses, pipefish, crabs, and invertebrates (Unsworth et al., 2019). Juvenile fish shelter among the leaves, avoiding predators, while invertebrates feed on detritus from decaying seagrass.

From an ecological perspective, seagrass is a primary producer. It photosynthesises, captures sunlight, and produces oxygen, but also contributes to the detrital food chain. Leaves die back seasonally, creating detritus that feeds decomposers, supporting higher trophic levels. Seagrass supports grazing and detrital pathways in this way, making it a cornerstone of coastal food webs (Duffy, 2006).

And let us not forget humans. Healthy seagrass beds underpin fisheries, stabilise sediments, improve water clarity, and store large amounts of carbon in their soils. This “blue carbon” function means they are natural allies in the fight against climate change.

Seagrass Physiology and Climate Change

Seagrasses are uniquely adapted to life under the sea. Their leaves contain air-filled spaces (aerenchyma) that help transport oxygen to the roots buried in sediment, where oxygen is scarce. They can withstand fluctuating salinity, tidal exposure, and sediment burial.

However, climate change is testing their limits. Rising sea temperatures stress photosynthesis, while stronger storms and sea-level rise increase sedimentation and physical disturbance. At the same time, nutrient enrichment from sewage and agricultural runoff causes algal blooms, which block light and smother seagrass beds (Waycott et al., 2009).

Adaptations exist: seagrasses can shift flowering times, change growth rates, or expand into new ranges as waters warm. However, these adaptations would be insufficient without human action to reduce pressures. Globally, seagrass meadows are declining at a rate of ~7% per year, similar to tropical rainforest loss (Waycott et al., 2009).

Threats: From Cornwall to the World

The pressures seagrass faces in Cornwall mirror those seen worldwide:

Physical disturbance: Anchors, boat moorings, and dredging uproot plants.

Pollution: Nutrient and chemical runoff reduce water clarity and cause algal blooms.

Climate change: Heatwaves, storms, sea-level rise.

Disease: The wasting disease (Labyrinthula zosterae) devastated Zostera in the 1930s.

In Cornwall, one of the biggest threats comes from anchoring. Boats dropping anchor can rip out large clumps of seagrass. That is why No Anchor Zones, marked by buoys, have been established in the Fal & Helford Special Area of Conservation (SAC). These voluntary zones encourage responsible boating without restricting access.

The Falmouth Seagrass Restoration Project

In 2025, Cornwall Council and partners launched an ambitious project to restore seagrass in the Fal & Helford SAC. Here are the highlights:

Scale: Restore 10 hectares of seagrass over three years.

Techniques: Use the innovative OCToPUS seeding device (developed by the Ocean Conservation Trust) and transplant cultivated adult seagrass grown in hessian pillows.

Monitoring: Detailed baseline surveys, seed collection, and ecological monitoring to measure biodiversity, carbon storage, and success rates.

Community involvement: Citizen science programmes, seagrass monitoring, and outreach campaigns to ensure local buy-in.

Protection: Work alongside voluntary No Anchor Zones to reduce disturbance.

As the organisers put it:

“This two-pronged approach is great for restoring seagrass habitats at scale, with this project setting an ambitious goal to restore 10 hectares of seagrass over the next three years.” (Falmouth Seagrass Project, 2025)

It is a bold plan; it could act as a model for restoration across the UK.

Seychelles: Lessons from Island States Protecting Seagrass

Seychelles, an archipelago nation in the Indian Ocean, leads on several fronts that Cornwall might learn from or collaborate with. Their approach shows how restoration, mapping, policy, community engagement, and blue carbon strategies can come together.

Here are a few of their standout achievements:

Mapping & Carbon Assessment

Seychelles has nearly mapped all its seagrass meadows and quantified how much carbon they store. The Seychelles Seagrass Mapping and Carbon Assessment Project (SeyCCAT, Pew, University of Oxford, etc.) is field-validating maps and sampling sediments to understand carbon stocks (SeyCCAT).
Similar efforts are underway in Cornwall: the University of Exeter and partners are assessing blue carbon potential in local seagrass and seaweed habitats (Blue Carbon Cornwall; Exeter University news).

Partnerships & Innovation

NGOs, the government, and international science teams support collaboration in Seychelles. In Cornwall, projects like South West Water’s initiative ask whether seagrass can come back (South West Water).

National Policy & Protection

Seychelles has committed in its Nationally Determined Contribution (NDC) under the Paris Agreement to protect 100% of its seagrass by 2030. It has also developed a Marine Spatial Plan and enforceable protections across large parts of its waters (Pew Charitable Trusts).
Cornwall and the wider UK might mirror this ambition through frameworks like the Wildlife Trusts Strategy 2030, the Cornwall Wildlife Trust Strategy 2030 PDF, and national goals such as the UK’s 30by30 target.

Community & Local Knowledge

Seychelles integrates local stakeholders, including fishermen, by identifying species, naming them in Creole, and involving them directly in management. This approach builds respect, awareness, and ownership (Dugong & Seagrass Hub).
Cornwall also has strong community engagement through the Cornwall Wildlife Trust’s seagrass restoration work and broader frameworks such as the Marine Nature Recovery Framework. Divers and ocean advocates are also invited to participate through global efforts (PADI Seagrass Restoration).

Comparing Cornwall & Seychelles: What Cornwall Can Share

Potential collaboration ideas:

Joint research projects comparing carbon sequestration rates in temperate Zostera marina meadows (Cornwall) vs tropical/subtropical species (Seychelles).

Exchange of good practice on boating regulation (e.g. how Seychelles enforces marine spatial plans, voluntary vs legal anchor zones) and public outreach materials.

Shared toolkits / open data for mapping and remote sensing.

Dive-based citizen science exchanges: divers from Cornwall visiting Seychelles or vice versa to share sampling & monitoring techniques.

Volunteering and Diving Into Conservation

Currently, there are no direct volunteering roles while funding and permits are secured. However, the project team encourages people to:

Join the Falmouth Marine Conservation Group

Sign up for the Fal & Helford SAC newsletter

During the webinar, a diver asked how they could help. The reply: You must be an SSI or PADI Advanced Open Water Diver with your equipment.

As I work toward that level, I am reminded that diving is not just an adventure but a conservation skill. Every speciality course and dive I log brings me closer to contributing meaningfully to the field. Combining science, conservation, and diving feels like building a bridge between personal passion and global need. Diving gives me peace and calm, yet it also demands responsibility. To play my part, I need to master buoyancy control, because poor control can harm the seabed I hope to protect.

Why Seagrass Matters to Communities

Seagrass restoration is not just about saving plants. It is about protecting livelihoods, fisheries, and coastlines. It is about ensuring our children inherit oceans that still teem with life.

In Cornwall, restored meadows could support local fisheries, enhance eco-tourism, and improve coastal resilience. On a global scale, seagrass conservation is part of achieving climate goals. If we protect and restore these meadows, we safeguard not only biodiversity but also our own future.

How You Can Make a Difference

Be mindful at the beach: Avoid trampling intertidal eelgrass (Z. noltii) and anchor responsibly if boating.

Join local groups: Support organisations like the Falmouth Marine Conservation Group in Cornwall, but local to you.

Stay informed: Subscribe to the Fal & Helford SAC newsletter; whether you are a Cornish resident or not, you can still stay informed.

Raise awareness: Share blogs, photos, and facts about seagrass. The more people know, the more they care.

Support restoration projects through donations, citizen science, or spreading the word.

Divers: Train up! Conservation diving requires skills and safety; the ocean needs prepared and trained divers.

To Conclude: Restoring Hidden Meadows

Seagrass might not grab headlines like coral reefs or mangroves, but without it, our coasts and oceans would be poorer, less resilient, and less alive.

The Falmouth Seagrass Restoration Project is more than just a local effort; it is part of a global movement to restore ecosystems we have long neglected. Cornwall has both the need and the opportunity. Lessons from places like Seychelles show what is possible when science, policy, protection, and community unite.

Protecting these underwater meadows is protecting ourselves. When you walk along the Fal, Helford, or any Cornish beach, take a moment to imagine the world just below the surface: a green, swaying meadow, sheltering life, storing carbon, and reminding us that the future of the ocean depends on what we do today.

References

Duffy, J. E. (2006). Biodiversity and the functioning of seagrass ecosystems. Marine Ecology Progress Series, 311, 233–250. https://doi.org/10.3354/meps311233

Falmouth Seagrass Project (2025). Let’s Talk Cornwall – Falmouth Seagrass Restoration. Available at: https://letstalk.cornwall.gov.uk/falmouthseagrass

Green, E. P., & Short, F. T. (2003). World Atlas of Seagrasses. University of California Press.. Available at https://environmentalunit.com/Documentation/04%20Resources%20at%20Risk/World%20Seagrass%20atlas.pdf

Lee, C. B., et al. (2023). Mapping the national seagrass extent in Seychelles using satellite imagery. Remote Sensing, 15(18), 4500. https://doi.org/10.3390/rs15184500

Orth, R. J., et al. (2006). A global crisis for seagrass ecosystems. BioScience, 56(12), 987–996. https://doi.org/10.1641/0006-3568(2006)56[987:AGCFSE]2.0.CO;2

Pew Charitable Trusts (2023). To protect its valuable seagrass, Seychelles leverages partnerships. Available at: https://www.pew.org/en/research-and-analysis/articles/2023/10/10/to-protect-its-valuable-seagrass-seychelles-leverages-partnerships

Project Seagrass. (n.d.). ProjectSeagrass.org. Available at: https://www.projectseagrass.org/

SeyCCAT (2024). Seychelles Seagrass Mapping and Carbon Assessment Project. Available at: https://seyccat.org/seychelles-seagrass-mapping-and-carbon-assessment

The Nature Conservancy (2023). Seychelles Nature Bonds – Marine Spatial Planning. Available at: https://www.nature.org/en-us/what-we-do/our-insights/perspectives/seychelles-nature-bonds-msp

Unsworth, R. K. F., et al. (2019). Global challenges for seagrass conservation. Ambio, 48, 801-815. https://doi.org/10.1007/s13280-018-1115-y

Waycott, M., et al. (2009). Accelerating loss of seagrasses across the globe threatens coastal ecosystems. Proceedings of the National Academy of Sciences, 106(30), 12377-12381. https://doi.org/10.1073/pnas.0905620106

Wildlife Trusts (2023). Strategy 2030. Available at: https://www.wildlifetrusts.org/strategy-2030

Cornwall Wildlife Trust (2024). Strategy 2030. Available at: https://www.cornwallwildlifetrust.org.uk/sites/default/files/2024-03/CWT-Strategy-2030-WEB_0.pdf

UK Government (2023). Criteria for 30by30 on land in England. Available at: https://www.gov.uk/government/publications/criteria-for-30by30-on-land-in-england/30by30-on-land