In an article for Halloween, Grace Cutler, one of Project Seagrass’ Interns for the 2025-26 academic year, explores the frightening reality of continued seagrass loss as a result of anthropogenic activity and how this in turn threatens seagrass’ role in supporting people and planet. Werewolves are struck down by silver
Dr Richard Unsworth, Chief Scientific Officer at Project Seagrass, along with 35 other leading scientists from across the UK, responds to proposals from the UK government to make licensing for marine restoration more complex and costly. Dear Rt Hon Steve Reed OBE MP and team, This letter sets out our
 Hurricane Irma – one of the strongest on record to hit the Caribbean – recently scoured the islands leaving catastrophic damage in its wake. And just as we began to piece together the devastating and potentially long–term impacts of Irma, Hurricane Maria has now left another path of destruction.
In an article for Halloween, Grace Cutler, one of Project Seagrass’ Interns for the 2025-26 academic year, explores the frightening reality of continued seagrass loss as a result of anthropogenic activity and how this in turn threatens seagrass’ role in supporting people and planet. Werewolves are struck down by silver bullets, vampires are defeated with wooden stakes; the environment is protected by seagrass. While it may not be as dramatic, the narrative that aligns seagrass as the ultimate solution to combating the environmental crisis is popular. As someone studying this remarkable habitat, it’s easy to see why. The only marine flowering plant in the world, seagrass offers numerous ecological benefits, supporting both our planet and humanity. Despite this, we risk ignoring the crux of the issue by relying on these green solutions. We keep polluting. It is because we continue to pollute our environment, be it through greenhouse gases, plastic pollution, or general waste production, that the very things that help to prevent the environmental crisis, are dying. A Natural Water Filter? While seagrass may not clean water bodies, it increases particle deposition rates by slowing the speed of waves and allowing more time for particles to sink to the ocean floor. Particles can then become trapped in the seagrass meadow and are prevented from ending up elsewhere in waterways. This process has been shown to capture excess nutrients, waste products, and even pathogens. A study conducted in the greater Seattle Metropolitan Area showed that mussels placed in seagrass habitats had 65% less relative abundance of some pathogens when compared to mussels placed in habitats without seagrass. Yet, the most apparent threat to seagrass, identified by UK researchers, is water quality. Like most plant species, seagrass can function in polluted water quality up to a point or ‘threshold value’. Similar to how humans can eat a certain number of toffee apples until it becomes too much and we get a sugar crash. Once this threshold is exceeded, seagrass will decline and, in some severe instances, disappear from the environment entirely. One such instance can be seen in the Chinese province Hainan, where researchers found that a dissolved inorganic nitrogen concentration of 8μM or above will cause seagrass meadows to disappear. This is because an excess of nutrients in water bodies, like nitrogen, stimulates the production of algae which blooms on the surface of the water and prevents sunlight from reaching seagrass beds. Additionally, some nutrients like ammonium and sulphides can have direct negative effects on seagrass growth. Fortifying our Coastlines Imagine a castle that is under attack. If it is strong and maintained, the castle will be better at defending itself against intruders. However, the next time it is under attack, there are holes and weak points left in it from the previous battle. Over time, this castle falls into disrepair and becomes a ruin, leaving it unable to protect its inhabitants. Seagrass is similar. Its inhabitants are our coastlines. Coastlines today are facing threats on all fronts. Sea level rise, extreme storms, and erosion are just some of the problems they experience. With that said, some have considered using seagrass as a way of minimising the impact of storms causing erosion in these areas. Through their matted root systems, called rhizomes, seagrass meadows have been shown to improve the stability of sediments and reduce wave energy before it reaches the shore in some hydrodynamic systems. Yet, seagrass is also harmed by these storms. Meadows that are struck by intense physical disturbances can be uprooted or die back, initiating a positive feedback loop where meadows in decline are more vulnerable to disturbances. This means when the next storm hits, seagrass not only will be more susceptible to decline, but they are also less able to protect our coasts. What About Carbon? Carbon storage is a phrase often thrown around. It may be the key reason why people are interested in seagrass as an answer to climate change. With anxiety surrounding our warming planet on the rise, this isn’t unprecedented. However, seagrass may not be quite the antidote we think it is. Recent evidence has shown that following disturbances, carbon stored in the soil of meadows may be re-released into their environment as carbon dioxide. Such disturbances can range from direct physical effects, such as dredging and construction work, or indirect global threats stimulated by climate change. A 2011 marine heat wave struck the West-coast of Australia, causing the reported loss of over 1000 km2 of seagrass in Shark Bay. Another instance of mass seagrass loss occurred in the Gulf of Mexico, where two seagrass species (Halodule wrightii and Syringodium filiform) disappeared following sea level rise in 2014. Without seagrass, the carbon stored in these soils is easily remineralised and released back into the environment. What’s Next? Thankfully, the main factor contributing to seagrass decline appears to be anthropogenic impacts such as dredging, overfishing, and agricultural runoff. This means that with changes in how we do things, we can stop the death of seagrass. However, this means seagrass mustn’t be painted as a plaster to patch up the pollution of the planet. To help seagrass, we must reduce pollution, reduce nutrient runoff, protect seagrass so it can protect us! References Ranking the risk of CO2 emissions from seagrass soil carbon stocks under global change threats Extreme climate events lower resilience of foundation seagrass at edge of biogeographical range Too hot to handle: Unprecedented seagrass death driven by marine heatwave in a World Heritage Area Rapid sea level rise causes loss of seagrass meadows Seagrass ecosystems as green urban infrastructure to mediate human pathogens in seafood Toxic effects of increased sediment nutrient and organic matter loading on the seagrass Zostera noltii Losses and recovery of organic carbon from a seagrass ecosystem following disturbance Continual migration of patches within a Massachusetts seagrass meadow limits carbon accretion and storage Mediterranean seagrasses provide essential coastal protection under climate change
Dr Richard Unsworth, Chief Scientific Officer at Project Seagrass, along with 35 other leading scientists from across the UK, responds to proposals from the UK government to make licensing for marine restoration more complex and costly. Dear Rt Hon Steve Reed OBE MP and team, This letter sets out our response as leading scientists, practitioners, and NGOs to the DEFRA consultation “Marine licences: changes to fees, exemptions and self-service licences”. We believe the proposed increases in fees and restrictions for marine licences will seriously undermine restoration efforts, making an already difficult activity even more challenging and, in many cases, unviable. The current licensing system for marine restoration is already unjust and fundamentally at odds with the UK Government’s national and international commitments. To introduce additional fees, administrative burdens, and restrictions at this time is, quite frankly, perverse. We specifically oppose: Any increase in fees for marine restoration licences. The urgent need is to remove fees entirely, not add to them. Further restrictions and additional charges on marine restoration projects larger than 5 hectares (we need marine restoration exemptions from this). Evidence clearly shows that scaling up restoration delivers greater resilience and enhanced ecosystem service (natural capital) benefits compared with small, fragmented projects. We specifically request: Practitioners need DEFRA to create a simplified, consistent, cost-free, and science-based licensing system for marine and coastal conservation. Currently, licensing is one of the most significant barriers to restoring the health of the UK’s seas. We see these proposed changes under the consultation as a missed opportunity to create such a system. The urgency could not be greater. Our climate and natural systems are breaking down, and the ocean is in crisis. In each of the last three summers (2023–2025), UK seas have endured unprecedented marine heatwaves. Never before has there been such a critical need for healthy coastal ecosystems that can bolster resilience, buffer climate impacts, and support food security. Yet our habitats have been decimated and continue to decline with DEFRA’s own assessment concluding that the UK marine environment is failing on 13 out of 15 indicators. Marine restoration is not optional; it is essential for our collective future. Restoring and conserving ocean habitats is also a legal obligation. The UK is a signatory to the Kunming–Montreal Global Biodiversity Framework and, under the Environment Act 2021, has binding targets for nature recovery. These commitments require all public bodies, including seabed owners to conserve and enhance biodiversity. The UK has already missed the Aichi Biodiversity Targets, largely due to regulatory barriers of the very kind now being proposed. Repeating these mistakes would be indefensible. The benefits of a streamlined licensing system are profound. It would enhance our capacity to tackle the climate and biodiversity crises, strengthen coastal resilience, and improve national food security. International examples demonstrate that simplified frameworks accelerate recovery and generate long-term ecological and social benefits. At conferences such as ReMeMaRe, UKSS, and the Seascape Conference, frustration with England’s current licensing regime has been a recurring theme. The system is widely regarded as unpredictable, inconsistent, costly, and burdensome, treating restoration projects as if they damage rather than enhance the marine environment. This not only delays urgent work but risks deterring vital investment in ocean recovery. The state of our marine environment illustrates the scale of the problem: estuaries are degraded, mudflats retreating, saltmarshes fragmented, and most seagrass meadows lost. Remaining habitats are scarce and highly vulnerable to climate change. Immediate reform is essential. Wales and Scotland are already moving in the right direction. Dialogue and regulatory reforms are creating enabling environments for restoration. England must now do the same. Without urgent change, regulation will remain a barrier to the large-scale environmental renewal that is desperately needed. We no longer have healthy ecosystems to use as restoration baselines. Historic habitats such as oyster reefs have vanished, while global heating accelerates ecological change. Restoration must therefore look forward, building climate-resilient ecosystems that reflect future needs rather than only past states. To do so, we need a legal and regulatory framework that supports ambition. The Kunming–Montreal Framework and the Environment Act 2021 require bold action, but these targets cannot be met without enabling legislation. In addition to the consequences of further restrictions on marine restoration for biodiversity, we also believe these restrictions place further restrictions upon our ability to reach Net Zero, and therefore see this as an issue not only for DEFRA but also for DESNZ. We therefore call on the Government to act swiftly to reform the licensing system for marine and coastal restoration. This is a practical and achievable step that would deliver immediate benefits for biodiversity, climate resilience, and food security. As scientists and practitioners at the forefront of UK marine research and restoration, we would welcome the opportunity to meet with you and your team to discuss solutions and pathways for progress. Yours sincerely, Dr Richard Unsworth FRSB, FHEA Associate Professor (Swansea University), Chief Scientific Officer (Project Seagrass) Signed on behalf of the following: Prof Martin J Attrill, Professor of Marine Ecology, University of Plymouth Dr Dan Barrios-O’Neill, Head of Marine Conservation, Cornwall Wildlife Trust Prof Michael Chadwick, King’s College London Sarah Chatfield, Nature Recovery Partnership Manager, Chichester Harbour Conservancy Dr Leanne Cullen-Unsworth, Chief Executive, Project Seagrass Dr Aline da Silva Cerqueira, Sussex Bay & King’s College London Dr Tim Ferrero, Senior Specialist – Hampshire & Isle of Wight Wildlife Trust Zia Fikardos, Marine Policy Officer, Royal Society for the Protection of Birds (RSPB) Angus Garbutt, Principal Scientist, UK Centre for Ecology & Hydrology Chris Graham, Head of Ocean Regeneration, Marine Conservation Society Tom Godfrey, Founder, Earth Change Dr Ian Hendy, Coastal Ecologist, Senior Lecturer, University of Portsmouth Chloë James, Seagrass Project Officer, Cornwall Wildlife Trust Prof Chris Laing, University of Exeter Dr Sally Little, Nottingham Trent University Louise MacCallum, Solent Seascape Project Manager, Blue Marine Foundation Niall McGrath, CEO, Robocean Ltd. Anouska Mendzil, Senior Science Officer, Project Seagrass & Swansea University Nigel Mortimer, Estuaries Officer, South Devon National Landscape Estuaries Partnership Dr Simon J. Pittman, School of Geography
 Hurricane Irma – one of the strongest on record to hit the Caribbean – recently scoured the islands leaving catastrophic damage in its wake. And just as we began to piece together the devastating and potentially long–term impacts of Irma, Hurricane Maria has now left another path of destruction. Puerto Rico, the British dependency of the Turks and Caicos, and many other Caribbean islands have suffered what have been described as “apocalyptic conditions”. When the world talks of the tragic and devastating consequences of severe hurricanes, the focus tends to be on the land, and the people who live in affected communities. Indeed, nearly 30 people have been reported killed, while Puerto Rico Resident Commissioner Jenniffer Gonzalez has said that the hurricane has set the country back by “20 to 30 years”. We see images of toppled trees, torn off roofs and severe flooding. But marine environments can be also badly affected by hurricanes, with potential long-term effects. The force of hurricane winds, and the resultant tides and waves are so strong that both plants and animals are ripped from the sea floor leaving lifeless rubble and sediment behind. Hurricanes have a washing machine effect: they mix up coastal sediments with knock-on effects for marine life. Suspended matter left floating in the water column limits the amount of sunlight that reaches marine habitats and so reduces growth and recovery. Meanwhile in shallow coastal environments, debris, sewage and run-off continue to flow in to the sea long after the hurricane has passed. Human dependency on the sea  The fishery for Queen Conch (Strombus gigas) is a major source of income to many around the Caribbean. The devastation of coastal environments, particularly seagrass meadows, can also result in long-term losses of the benefits that humans receive from them, such as fisheries support or coastal protection. Damage to these ecosystem services consequently impacts human well-being, because people can no longer rely on them for their livelihood and food supply. Some of the most severely affected areas of the recent hurricanes in the Caribbean – Florida, Turks and Caicos, Puerto Rico, Cuba and the British Virgin Islands – all house extensive seagrass meadows. These shallow water marine habitats support valuable lobster fisheries, as well as shrimp, conch, and finfish fisheries. Seagrass also stabilises sediments and protects the white sand beaches that attract so many tourists to the region. Previous hurricanes, cyclones, and typhoons (weather events which are essentially the same but have different names depending on where the storm happens) across the globe have shown the severe negative effects they can have on these vital seagrass meadows. The seagrass plants are ripped up or buried under sediments, leading to their suffocation. The extensive associated murky water leads to widespread loss of seagrass, as was seen in the years that followed hurricane Katrina hitting the US. Initial indications from the Everglades in Florida show that seagrass destruction in the wake of Irma is extensive, with large piles already being washed far onshore. This should ring alarm bells for Caribbean fisheries, as hurricanes Katrina and Rita led to losses in the seafood industry that reached billions of dollars. The Caribbean spiny lobster fishery business alone is worth more than US$450m, and directly employs 50,000 people. Healthy seagrass provides the best fishing grounds with the greatest revenue, and the recent hurricanes have the potential to decimate this. Environmental impact But this is not just about money. Seagrass loss also threatens marine biodiversity and the health of charismatic species. After a severe cyclone in Australia in 2011, turtles and dugong starved due to the damaged meadows. In addition, seagrass is a marine powerhouse, which stores vast amounts of carbon in meadow sediments. When the seagrass is removed, this carbon is released back into the environment.  Caribbean spiny lobsters depend on clams they find in seagrass. Hurricanes have always been a part of life in tropical seas. The destruction they cause and their recovery have been observed throughout human history. What is alarming now, however, is the apparent increased frequency and intensity. The already poor state of the Caribbean marine environment restricts the ability of habitats such as seagrass meadows and coral reefs to recover from the effects of severe storms. Poor water quality and over-fishing, for example, promotes the overgrowth of algae, preventing recovery. With repeated hurricanes occurring over time periods that are insufficient for recovery to occur, this will only get worse. The severity of hurricanes Irma and Maria are a wake up call. We need a fundamental shift in how marine environments are protected to enable long-term sustainability for the food and income they provide. Many locations in the Caribbean, for example Puerto Rico, have ineffective marine protection rules and so destructive practices continue unchecked, meaning that when a disaster does occur, the environment is unable to recover. Although local actions against climate change are difficult to achieve, it is possible to manage river catchments to improve water quality, and focus on small scale immediate actions, such as implementation of marine protected areas to limit immediate and direct damage to coastal resources. Coordinated small scale actions will ultimately help enhance the resilience of the Caribbean Sea, and make sure that the environment can better recover from any future extreme events. Richard K.F. Unsworth, Research Officer (Marine Ecology), Swansea University; Benjamin L. Jones, Research Assistant at the Sustainable Places Research Institute, Cardiff University; Leanne Cullen-Unsworth, Research Fellow, Cardiff University, and Lina Mtwana Nordlund, Researcher in coastal environmental sciences, Stockholm University This article was originally published on The Conversation. Read the original article.
