Nursery intern Iestyn Comey details how fishing in seagrass meadows can be great to improve mental health and are vital nursery grounds for key fisheries species. Fishing is a hard thing to explain to someone who has never done it. There is no better feeling than the moment the line
Extreme heat can have a devastating effect on seagrass, but new research from Edith Cowan University (ECU) could shape how these vitally important marine ecosystems are managed and restored. In separate studies carried out on both the west and east coasts of Australia, researchers have investigated how seagrasses stand up
Accelerate Seagrass is a collaborative program being delivered by Climate Impact Partners, Deloitte, Project Seagrass, and the National Oceanography Centre which aims to support groundbreaking research into seagrass carbon sequestration and unlock long-term finance to save and reinstate vital seagrass meadows. Part of this programme of work involves collaborating with community groups across Scotland to develop knowledge
The Scottish Seagrass Collaborative, responds to Crown Estate Scotland’s Approach to Marine Enhancement Proposals: We write as marine scientists, restoration practitioners, and organisations working across Scotland’s coasts and seas, in response to Crown Estate Scotland’s Approach to Marine Enhancement Proposals. We welcome Crown Estate Scotland’s commitment to responsible stewardship of
Two weeks ago, I joined colleagues and collaborators at the Coastal Futures Conference at the Royal Geographical Society in London. The theme this year was ‘From Ambition to Action’, a sentiment that seems to be playing on repeat across the conferencing world with, with yet and seemingly as always, not
In this blog series, our Conservation Trainee Abi David explores some of the amazing creatures that call seagrass meadows their home. The shore crab, also known as the green crab, are contentious within the seagrass world. They have important ecological roles within their habitats, but their tendency towards destruction and
In Dale Bay, Pembrokeshire, a collaboration between local fishers and marine conservation charity Project Seagrass is showing positive results for both sustainable fishing and seagrass restoration. Dale Bay is the location of an ongoing seagrass restoration project, delivered by South Wales based charity Project Seagrass and overseen by the Dale
Grammy-nominated singer and Solent Seascape Project collaborate with Jeremy Irons and Angela Harding to celebrate and protect the region’s coastal habitats. The Solent Seascape Project, of which Project Seagrass is a partner, has launched Songs from the Solent, a new EP by Grammy-nominated singer and songwriter Richard Walters that uses music to spotlight the Solent’s threatened coastal habitats
Grace Cutler, one of our 2025-26 Project Seagrass interns, reflects on Rebekah Bajkó’s research, Coastal Roots: The History of Seagrass in Northern Ireland. Northern Irish Seagrass In November 2025, I attended the UK Seagrass Symposium, an exciting conference hosted every two years to highlight the current state of seagrass research
Current estimates of the global extent of seagrass range from between 160,000-266,000km. Such a high degree of uncertainty presents challenges for researchers and managers and their ability to make informed decisions which account for the changing status of seagrass ecosystems. Key to improving our understanding of seagrass presence and absence,
Nursery intern Iestyn Comey details how fishing in seagrass meadows can be great to improve mental health and are vital nursery grounds for key fisheries species. Fishing is a hard thing to explain to someone who has never done it. There is no better feeling than the moment the line tightens, the adrenaline kicks in, and you pull up your first fish, completely absorbed in something so simple and ancient. Recreational fishing remains one of the most widely enjoyed outdoor pastimes. (Karpiński and Skrzypczak, 2022). But for many people, it is more than just a hobby. It’s a way to reset. It’s one of the few moments when everything slows down and you can think completely immersed in nature. It can be social, or it can be just you and the rod. Either way, that time outdoors—surrounded by nature, waiting and focusing—has a powerful effect on mental health and wellbeing. Science is beginning to catch up with what anglers have long known. Image of typical fishing line, a true way to be one with nature More than a feeling: fishing and mental health Recent UK research involving over 1,700 recreational anglers found that people who fish regularly experience significantly better mental health outcomes than those who fish less often (Wilson et al., 2023). Regular anglers were: 17% less likely to report being diagnosed with depression, schizophrenia, less likely to experience suicidal thoughts, less likely to report harmful coping behaviours. Nearly 9 in 10 anglers also reported that relaxation and unwinding were key reasons they go fishing. This aligns with a growing body of evidence showing that spending time in “blue spaces”—coastlines, estuaries, rivers, and seas— is linked to improved psychological wellbeing (White et al., 2010; Gascon et al., 2017). Blue Mind theory, introduced by Wallace J. Nichols, provides a framework for understanding this effect, suggesting that the mental health benefits of fishing largely arise from immersion in water and aquatic environments, rather than the act of fishing itself. What makes this even more striking is that anglers, as a group, report higher than average levels of mental health challenges. In the same UK study, around 30% reported experiencing suicidal thoughts and over 23% reported having been diagnosed with depression suggesting that many people may actively turn to fishing for its mental health benefits. Every catch has a beginning There is another part of this story that we rarely see. Many fish we love to catch do not begin life in open water, rocky shorelines, or deep offshore. Instead, they begin somewhere more sheltered and hidden. In seagrass meadows. In the UK alone, seagrass meadows provide habitat for around 50 fish species and serve as crucial nursery grounds for juveniles, including cod, pollack, whiting, plaice, herring, and sea bass (Bertelli & Unsworth, 2014). Our new paper in BioScience highlights that this nursery function directly underpins the cultural ecosystem service of recreational fishing, demonstrating that healthy seagrass habitats are integral not only to sustaining fish populations but also to supporting the human experiences and wellbeing derived from angling. Data from Catchwise, a collaboration between Substance, Cefas, and the Angling Trust, further reinforces this connection. Many of the species most frequently caught by recreational fishers in the UK, overlap with species that depend on seagrass during early life stages, showing the practical importance of protecting and restoring these habitats. Across the world, countless marine species rely on seagrass meadows for feeding grounds or during their earliest, most vulnerable stages of life. (James and Whitfield, 2022). Seagrass changes that equation. Its dense leaves slow water movement, trap nutrients, and create a three-dimensional maze that offers both shelter and rich feeding grounds. seagrass meadows support higher fish abundance, faster growth, and higher survival rates than bare sand (Whitfield, 2016). Even if the fish we catch eventually migrate far from the coast into deeper seas, estuaries, or rivers their survival often depended on those first months spent among seagrasses. Catshark in seagrass, Helford, Cornwall, UK Credit: Shannon Moran / Ocean Image Bank So why am I telling you this? The connection is simple: Fewer Seagrass meadows and fewer juvenile fish survive. Fewer fish and poorer catches. Poorer catches and fewer opportunities for people to access one of the most natural, affordable, and culturally accepted forms of mental wellbeing support available. Yet seagrass meadows are declining globally, and much of this loss is driven by human activity. In the UK, declining water quality is one of the biggest drivers. Runoff from agriculture carries excess nutrients in marine ecosystems fuelling algal blooms that block sunlight and as a result prevent seagrass from photosynthesising (Lee, Park and Kim, 2007). Physical disturbance is another key issue, particularly from commercial fishing and boating activity. Bottom trawling can tear up seagrass beds; while anchoring and mooring chains can scar and fragment them. Damage to these habitats ultimately reduces the productivity of the fisheries they support (Unsworth et al., 2017). Seagrass, Isles of Scilly, Cornwall, UK. Credit: Michiel Vos / Ocean Image Bank Protecting the places that protect our wellbeing As recreational fishers, we are connected to seagrass whether we realise it or not. If we want future generations to feel that same tug on the line and that same clearing of the mind, then protecting seagrass is not optional. Supporting seagrass restoration and conservation helps protect: Healthy fish populations, The future of recreational fishing And our own mental wellbeing. To get involved, visit Volunteer – Project Seagrass. References Bertelli, C.M. and Unsworth, R.K.F. 2014. Protecting the hand that feeds us: Seagrass (Zostera marina) serves as commercial juvenile fish habitat. Marine Pollution Bulletin 83(2), pp. 425–429. doi: https://doi.org/10.1016/j.marpolbul.2013.08.011. Gascon, M., Zijlema, W., Vert, C., White, M.P. and Nieuwenhuijsen, M.J. 2017. Outdoor blue spaces, human health and well-being: A systematic review of quantitative studies. International Journal of Hygiene and Environmental Health 220(8), pp. 1207–1221. doi: https://doi.org/10.1016/j.ijheh.2017.08.004. James, N.C. and Whitfield, A.K. 2022. The role of macroalgae as nursery areas for fish species within coastal seascapes. Cambridge Prisms: Coastal Futures 1.
Extreme heat can have a devastating effect on seagrass, but new research from Edith Cowan University (ECU) could shape how these vitally important marine ecosystems are managed and restored. In separate studies carried out on both the west and east coasts of Australia, researchers have investigated how seagrasses stand up to marine heat waves and prolonged ocean warming. Executive Dean of ECU’s School of Science, Professor Marnie Campbell, conducted the research during her time at Central Queensland University. She noted that insights into how different intertidal species respond to elevated water temperatures are critical for informing future seagrass management. “The outcomes demonstrate that the way we protect and restore seagrass will need to change as the climate warms,” Professor Campbell said. Ph.D. candidate Nicole Said from ECU’s Center for Marine Ecosystem Research said that not all seagrass species faced the same climate risk, with her research findings on Western Australian seagrass ecosystems indicating that subtidal seagrass meadows could be restored with more heat-resistant populations of the same species. “By identifying and sourcing heat-tolerant populations—sometimes just kilometers away—we can translate this knowledge into on-the-ground action, incorporating resilient populations into restoration to create climate-ready meadows,” Ms. Said explained. West coast Ms. Said is lead author of the study “Seagrasses are most vulnerable to marine heat waves in tropical zones: local‐scale and broad climatic zone variation in thermal tolerances,” which looked at six species along the Western Australian coast, spanning broad thermal gradients from temperate to tropical climates. The study is published in the journal New Phytologist. “Western Australia is an ideal setting for studying seagrass thermal tolerances, and there is a critical need for this data due to WA being a global hotspot for marine climate impacts,” Ms. Said explained. “We can use this information to look at which species might be vulnerable during future marine heat waves, and which ones we should focus our conservation value on.” The study revealed that seagrasses are most vulnerable to marine heat waves in tropical zones. It also showed that climate risk varied across seagrass species, with a 10-degree Celsius difference in thermal optima, and even neighboring populations showed different heat tolerances. “Some populations are better equipped to deal with the heat, and in some cases, the tough ones might be growing next door,” Ms. Said explained. “This shows that not all species face the same level of risk from climate change, and a one-size-fits-all approach is not appropriate for management of thermally vulnerable seagrass species.” The findings could also benefit restoration of seagrass meadows that have already suffered from thermal warming and marine heat wave events. “We can use this information to help build climate-ready meadows, by migrating plants or seeds from more heat-resistant populations into thermally vulnerable areas.” East coast Professor Campbell’s study “Varying vulnerabilities: Seagrass species under threat from prolonged ocean warming” is a paper published in Limnology and Oceanography that examined the impacts of elevated water temperatures on five intertidal species in Gladstone, Queensland, with a focus on improving seagrass restoration. “This study offers an understanding of how climate change might impact these seagrasses, whose ecological functions are not easily replaced once lost,” Professor Campbell said. “Seagrasses are a critically important ecosystem that provides food, shelter and nursery areas for a wide variety of marine life, so with changing climate, it is at risk in different ways. We wanted to understand how these species react when temperatures reach dangerous extremes, which is becoming more common with climate change.” Professor Campbell said they found intertidal pools where the water was more than 40 degrees for weeks on end. “The tide would go out, and the seagrass would be left high and dry, quite often in little, tiny pockets of water which would reach massive temperatures,” Professor Campbell said. “To restore or manage the species, you have to look at the distinct thermal thresholds of the different species—you can’t treat them all as one. “This knowledge helps us to decide which species to plant where—including the best substrate and water depth; so we can restore these ecosystems more effectively.” Professor Campbell said the species she studied were commonly found in Australia and other parts of the world, with the outcomes leading to global impact. “There were two species that were really good candidates for future-proofing restoration in regions that are warming up,” Professor Campbell said. “Two were highly vulnerable and will require more protection from heat stress, or if you’re going to restore them, you need to find micro-climates that are cooler for them—for example, if they are in the sub-tropics, you would look at temperate areas to restore them.” More information: This article is republished from PHYS.ORG and provided by the Edith Cowan University. Nicole Said et al, Seagrasses are most vulnerable to marine heatwaves in tropical zones: local‐scale and broad climatic zone variation in thermal tolerances, New Phytologist (2025). DOI: 10.1111/nph.70742 Marnie L. Campbell et al, Varying vulnerabilities: Seagrass species under threat from prolonged ocean warming, Limnology and Oceanography (2025). DOI: 10.1002/lno.70156
Accelerate Seagrass is a collaborative program being delivered by Climate Impact Partners, Deloitte, Project Seagrass, and the National Oceanography Centre which aims to support groundbreaking research into seagrass carbon sequestration and unlock long-term finance to save and reinstate vital seagrass meadows. Part of this programme of work involves collaborating with community groups across Scotland to develop knowledge of historic and current seagrass meadows and the threats facing Scottish seagrass today In this blog, our interns Ewan Garvey and Jasper Brown explain the process of site selection at Project Seagrass. Site selection is a process that allows Project Seagrass to identify locations where experimental work or restoration is most likely to succeed. It involves the analysis of existing information, suitability models, and field data. As seagrass meadows are complex ecosystems, these steps are necessary to ascertain the most suitable site for a work package to take place at. 1. Existing Information Often, the first aspect is creating a database of all information surrounding seagrass in the area, including: current and past research, intertidal maps, local knowledge and satellite images. Key information is gathered from: SeagrassSpotter – for recent presence of seagrass as well as species, area cover and sediment type. Historical records – often from local surveys carried out by councils and fisheries. This is used to try quantify the meadow recession or growth. ⁽¹⁾ By collecting this information, we validate the presence of seagrass at sites of interest, and begin to understand potential issues. A screenshot of Seagrass Spotter includes spotter points used in Buent Island survey 2. Habitat Suitability Modelling Habitat suitability modelling is used to compare the characteristics of viable sites. It uses data such as: Temperature, Bathymetry, Salinity, Light availability. The model is created through the use of software like MaxEnt, by inputting many datasets to quantify the likelihood of seagrass presence/ the ability of the environment to sustain seagrass. ⁽²⁾ Limitations: HSMs are only as good as the data they are based on Marine habitats often have very little data on them This means it’s only a small piece of a larger picture 3. Field Data collection and analysis In addition to the collection and modelling of existing data, we visit field sites to gather baseline monitoring data. Typically, we collect data on: the presence of seagrass, the health of the seagrass, reproductive state, and the local environment – such as sediment type. These datasets are collected through sediment and core samples as well as seagrass blade lengths and abundance counts. Common Difficulties: Land access – some sites can be quite remote, therefore making field surveys difficult. Permissions from both governing bodies and landowners. Ensuring the work doesn’t interfere with other projects on the land. 4. Selection By combining these data, the project lead, along with other experienced ecologists, can assess the suitability of each site for the proposed work package. Project Seagrass is currently working on a numerical system for grading the suitability of sites, to make site selection decisions more transparent. Once the most suitable sites are selected, Project Seagrass can begin to formally seek permissions from governing bodies and landowners. 5. Future Developments Site selection, just like seagrass science, is continuously evolving as new methods, theories and techniques are developed and tested. This means that the models used are constantly changing to produce more accurate and reliable results. Current Site Selection Research: LUSI scores allow the impacts of land on marine environments to be quantified. ⁽³⁾ Use of multiple models such as MaxEnt, cross validation, and threshold probability for model validation has been shown to produce more effective outputs. ⁽²⁾ A Habitat suitability model used for work in Burnt Island, Scotland References Thurstan, R.H., McClenachan, L., Crowder, L.B., Drew, J.A., Kittinger, J.N., Levin, P.S., Roberts, C.M. and Pandolfi, J.M. (2015). Filling historical data gaps to foster solutions in marine conservation. Ocean & Coastal Management, 115, pp.31–40. doi:https://doi.org/10.1016/j.ocecoaman.2015.04.019 Bertelli, C.M., Stokes, H.J., Bull, J.C. and K.F. Unsworth, R. (2022). The use of habitat suitability modelling for seagrass: A review. Frontiers in Marine Science, 9. doi:https://doi.org/10.3389/fmars.2022.997831. Flo, E., Garcés, E. and Camp, J. (2019). Land Uses Simplified Index (LUSI): Determining Land Pressures and Their Link With Coastal Eutrophication. Frontiers in Marine Science, 6. doi:https://doi.org/10.3389/fmars.2019.00018..
The Scottish Seagrass Collaborative, responds to Crown Estate Scotland’s Approach to Marine Enhancement Proposals: We write as marine scientists, restoration practitioners, and organisations working across Scotland’s coasts and seas, in response to Crown Estate Scotland’s Approach to Marine Enhancement Proposals. We welcome Crown Estate Scotland’s commitment to responsible stewardship of the seabed and its recognition that marine enhancement activities—such as seagrass meadow and native oyster restoration—deliver important public benefits. We also recognise the intention behind the Non-Commercial Enhancement Licence to provide a light-touch mechanism to support this work. However, we are concerned that the approach, as currently set out, risks creating unintended barriers to marine science, restoration, and climate action in Scotland—particularly through the inclusion of low-impact scientific surveys and sediment sampling (such as coring) within licensable activities. We ask: a zero-cost exemption for non-commercial, not-for-profit restoration activities to incentivise biodiversity positive activities rather than impose barriers and work collaboratively in consultation with the research and restoration community to develop all current and future guidance. Why sediment sampling matters Sediment coring and similar sampling methods are essential scientific tools. They are used to: identify and map habitats that store “blue carbon”; measure how much carbon is currently stored, and how much could be restored; design effective and well-targeted restoration projects; monitor whether restoration is successful over time; meet Scotland’s national and international obligations on climate and biodiversity reporting. These activities are temporary, small-scale, and reversible. A typical sediment core affects an area measured in centimetres, not metres, and causes negligible environmental impact. Treating this type of research in the same way as seabed occupation, construction, or extractive use risks undermining proportionality and evidence-based decision-making. Risks to restoration and blue carbon science Scotland is recognised internationally for leadership in marine nature-based solutions and blue carbon research. Yet marine carbon cannot be measured or verified without physical sampling of seabed sediments. Requiring licences, fees, and extended approval timelines for this work risks: creating significant barriers to non-commercial marine restoration at a time when policy and science point toward the need for rapid development and scale-up. Applying fees and additional bureaucracy to generative, public-benefit restoration is counterproductive and misaligned with national biodiversity and climate goals. Marine habitat restoration is non-commercial, non-extractive, and enhances seabed value delivering public benefits (blue carbon, fish nurseries, nutrient remediation) that exceed licence costs. slowing down urgently needed research at a time when climate and biodiversity action must accelerate. Non-Commercial Marine Habitat Restoration in Scotland is currently driven by small non-profit eNGOs and community-led projects that struggle for funding. For example, the charity Seawilding is trialing seagrass and native oyster restoration methodologies in multiple sites in Argyll and Wester Ross. Along with others, the charity is developing the science, the know-how, and the methodologies to allow restoration at scale. The existing licensing regime and cost is already burdensome. To pile on more poses an existential threat to Seawilding and this essential work. creating barriers to delivering the Scottish Biodiversity Strategy to 2045 and the Marine and Coastal Restoration Plan. The proposed charges are counter to the Strategy & Plan, which encourages active restoration by community-based organisations and advocates streamlining and simplifying the process. In addition, the charges will create additional barriers to achieving targets in the Scottish Biodiversity Strategy to 2045 and the upcoming Natural Environment Scotland bill. Recent work by a panel of expert restoration researchers and practitioners highlighted that adding licensing costs and complexity makes small-scale restoration increasingly unfeasible and favours large developers without restoration expertise. Read more here. making publicly funded research harder to deliver within fixed budgets and timelines. discouraging foundational science before any future natural capital markets are even considered. adding bureaucracy where policy intent is to enable, not constrain, restoration. While the policy excludes natural capital markets, the paradox is that the research needed to responsibly inform any future policy on blue carbon is now harder to carry out. All public bodies, including seabed owners, have duties to support biodiversity recovery and climate action. Those goals cannot be met without access to the seabed for scientific research. Our request We respectfully ask Crown Estate Scotland to: Explicitly exempt low-impact, non-commercial scientific sampling (including sediment coring) carried out for research, restoration design, monitoring, and blue carbon assessment from licensing requirements; or Introduce a clear, fast-tracked, cost-free notification or consent process for these activities, separate from enhancement or occupation licences; and Work collaboratively with the research and restoration community to develop guidance that recognises the essential role of scientific sampling in delivering national biodiversity, climate, and nature-recovery objectives. Closing We strongly support Crown Estate Scotland’s ambition to be a responsible and proactive steward of the seabed. We believe this ambition will be best realised by ensuring that essential scientific research is enabled rather than hindered. Applying fees and additional bureaucracy to low-impact, public-benefit restoration science risks creating significant unintended barriers at a critical moment for Scotland’s seas. We ask for the Crown Estate to incentivise biodiversity positive activities rather than impose barriers such as this licensing and fee. Letter endorsed by: Action West Climavore Loch Dail an Inbhire croft Heriot Watt University Moray Ocean Community Open Seas Project Seagrass Scotland’s Rural College Seawilding Shark and Skate Scotland Solway Firth Partnership University of Edinburgh University of Glasgow
Two weeks ago, I joined colleagues and collaborators at the Coastal Futures Conference at the Royal Geographical Society in London. The theme this year was ‘From Ambition to Action’, a sentiment that seems to be playing on repeat across the conferencing world with, with yet and seemingly as always, not enough action. But once again, this auditorium was full of people who care deeply and are pulling in the same direction. There was also an energy to the conversations—a shared sense that 2026 must be a year of action. In a world that often feels heavy, that collective intent felt genuinely hopeful. A clear theme threaded through the Coastal Futures sessions: action through collaboration. Joined voices carry further than fragmented ones. When our messaging is connected and our skills pooled, we create a far more powerful vehicle for change. The positivity and willingness to collaborate on display suggest that the moment is ripe—if we choose to seize it. There is, after all, only one sea. We can divide it on maps and draw lines across it, but it remains one interconnected system, another sentiment that was articulately woven throughout the conference. It belongs to all of us and to no one. With the knowledge and capacity, we now have, we also share responsibility—for protecting the sea and, in doing so, protecting ourselves. That responsibility is sharpened by the evidence. The Office for Environmental Protection reminded us that data continues to point to the biodiversity and habitat decline in the UK. The failure to meet Good Environmental Status targets by 2020 is not a footnote; it’s a warning. The OEP’s work—Improving Nature at Sea—is vital in holding government to account for commitments and targets that should underpin a healthy marine ecosystem. Evidence driving action in Wales including seagrass Talk from Huw Irranca-Davies MS: Deputy First Minister and Cabinet Secretary for Climate Change and Rural Affairs Language matters too. A shift has moved us from “limiting climate change” to “limiting the impacts of climate change.” That may be pragmatic, but it risks normalising loss. Many of the pressures on the sea are invisible; that invisibility is part of the problem. Our job—as scientists, practitioners, and communicators—is to make those pressures visible and to bring people with us on the journey from understanding to caring, and from caring to acting. One message that resonated strongly: lack of data cannot be an excuse for inaction. We know enough to act now for ocean recovery. Yet policy choices still too often permit destruction—sometimes even licensing it—through so-called compensatory measures. The framing of “wider compensation measures” from Defra risks enabling loss in one place to be offset by something entirely different elsewhere. This is not recovery; it’s displacement. We should be asking harder questions. Why are we still bowing to what large corporates and developers want—or will accept—when we are on a deep dive toward environmental collapse? Environmental stability and recovery must be the absolute priority if we are to continue to live well on this planet. Allowing any commercial interests to dictate the marine conservation agenda, or to profit from recovery after driving degradation, is a path we should challenge. That is why purpose matters. Project Seagrass is not-for-profit, but for people and for the planet. The work is about recovery that is ecological, social, and lasting—not transactional. As we look ahead—to questions about how restoration and monitoring feed into delivery routes, how nature portals are designed, where data comes from, and how progress is tracked—I’m hopeful. The conversations at Coastal Futures showed a community ready to move from words to work. If we keep our voices joined, our priorities clear, and our actions bold, this really can be the time we change course for the better. Ministerial Address by Emma Hardy MP – Minister for Water and Flooding
In this blog series, our Conservation Trainee Abi David explores some of the amazing creatures that call seagrass meadows their home. The shore crab, also known as the green crab, are contentious within the seagrass world. They have important ecological roles within their habitats, but their tendency towards destruction and invading habitats has led to them becoming a problematic species. The green crab is a species of variety. They live in shallow marine and estuarine habitats, generally preferring sheltered environments with muddy or sandy sediments. Adults can tolerate a broad spectrum of salinities – between 4 to 52 parts per thousand – and temperatures – from 0 to 30°C. However, this differs between populations, with some being more tolerant than others to change. There is also a wide range of colour variations within the species. Individuals can be green, brown, grey or red and this is largely dependent on local environmental conditions but does also have a slight genetic component. For instance, red-coloured individuals have been linked with delayed moulting and a tendency to have thicker carapace and increased aggression. However, they are less tolerant of environmental stress as a result of a higher metabolic demand compared to green individuals. Crabs have a hard exoskeleton called a carapace. Once or twice a year they will moult their carapace, usually at night. Each moult will increase the body size by 20-33%. The process starts with the crab absorbing calcium carbonate from the old skeleton. Enzymes then break down tissue connections to the old shell as muscles and tissues start secreting a new, softer shell. Absorbing seawater helps the crab puff up like a balloon, cracking the old shell and allowing the crab to climb out. It takes a few weeks for the new shell to harden. In the meantime, the crab continues to fill its tissues with seawater whilst the new shell is soft, ensuring there is plenty of room for growth. Juveniles can moult up to 10 times within their first year if conditions are good, but after reaching maturity will generally only moult once a year. Seagrass with a Green Shore crab (Carcinus maenas), Isles of Scilly, Cornwall, UK Credit Michiel Vos Ocean Image Bank Like a lot of species, green crabs can be affected by parasites. One of the most common parasites they become infected with is the crab hacker barnacle Sacculina carcini. When crabs are at their most delicate after moult, the barnacle can infect its host by injecting a chitin needle into the host and crawling inside the main body cavity of the crab. Once attached, it spreads tendrils inside the host crab, taking over the stomach, intestines, and nervous system to allow the parasite to absorb nutrients and control the hosts behaviour. The parasite will lay eggs on the crabs body and due to the parasites control over crab behaviours, the crab will protect these eggs like they are its own. At this point you may be thinking – that’s pretty grim, but what is cool is the infection effectively castrates male crab hosts and causes them to develop female characteristics and if for whatever reason the parasite is removed from the host, female crabs tend to regenerate their ovaries, but for males, permanent sex change occurs and ovarian tissue develops. As a result of their tolerance to a wide range of conditions, shore crabs are incredibly invasive – even being listed as one of the top 100 invasive species, a list dedicated to the worlds most harmful invasive species that can seriously impact ecosystems. The species is native to the North-East Atlantic and Baltic sea but has colonised areas of Australia, South Africa, South America and both coasts of North America. Global shipping routes are the main cause of this spread. As microscopic larvae, the crabs get caught up in ship ballasts and are transported around the globe. They can also spread due to sea planes, packing materials like seaweeds used to ship live marine organisms and inside bivalves that are moved for aquaculture. What is the link between green crabs and seagrass? Up until now you may have been thinking ‘green crabs are just going about their business, what’s wrong with that?’ but people trying to restore seagrass may disagree with you. There are anecdotal stories from restoration teams and scientists who have been out planting seagrass shoots only to spot a crab scuttling along behind them and pulling out the freshly planted seagrass shoots. Studies have found crabs can damage seagrass when they dig about in the sediment for clams and other invertebrates as this process of bioturbation exposes and uproots shoots. At our nursery in Laugharne, we have spotted seagrass leaves that appear to have been snipped or ripped out by crabs, and seeds mysteriously disappearing after being planted. However, these problems tend to be most prevalent where they are invasive and there are low numbers of predators. In habitats where they are native and numbers are under control – destructive behaviours have a reduced impact and are just a natural part of the ecosystem. Like any creature, crabs have an important niche within their natural habitats. As a generalist feeder, they scavenge and eat dead creatures and detritus on the sea floor that otherwise would rot and cause nutrient build up, which can potentially lead to disease. By eating a wide variety of prey, they help keep populations under control. However, where green crab are invasive or numbers are too high, this can become detrimental. Seagrass meadows are home to a lot of the species crabs will eat, so act as an all-day buffet. Additionally, young crabs are more vulnerable to predation and seek refuge amongst seagrass, with leaves providing cover from birds and fish swimming around above. In areas where they are invasive and populations are too high, it is becoming a popular solution for people to eat them. In New England for example, invasive crab populations are high. In 2019 ‘The Green Crab Cookbook’ was released where each recipe
In Dale Bay, Pembrokeshire, a collaboration between local fishers and marine conservation charity Project Seagrass is showing positive results for both sustainable fishing and seagrass restoration. Dale Bay is the location of an ongoing seagrass restoration project, delivered by South Wales based charity Project Seagrass and overseen by the Dale Seagrass Stakeholder group (a group made up of local individuals across different sectors). The project began as a way to boost the natural seagrass meadow in the bay, trialling new techniques and raising awareness of the importance of seagrass for local biodiversity, water quality, and fish populations. Mark from Lilly May Fishing has worked with Project Seagrass from the start of the project to assist in site selection and deploying monitoring equipment. As the project has progressed, Mark noticed he was sometimes tearing up seagrass as he lifted his pots up to retrieve crab and lobster. In response to this, Mark designed a raised shellfish pot with short mesh legs to lift the gear just off the seabed. Made by local boat builders Robust Boats, the pots were deployed over the last two seasons with catch monitored over that time. Early results are positive showing that the new pot design is effective for storing crab catch, with some tweaks required for lobsters, whilst also reducing mud build-up and reducing the impact on the seagrass. Mark reported: “Overall, [it has] worked very well in seagrass – I would recommend using them as storage pots in shallow water where seagrass is as it’s very low impact on the grass with the mesh legs compared to steel bar bottoms” Project Seagrass is continuing to plant seagrass in Dale Bay alongside carrying out regular monitoring to determine seagrass recovery and resilience. It will be interesting to see how the natural meadow responds to the reduced impact from shellfish pots over time. Seagrass caught in pots (credit Mark Gainfort) Seagrass growing in Dale Bay, Pembrokeshire. Beyond Dale Across South & West Wales, fishers, anglers, spearfishers, aquaculture workers, and seafood gatherers have been taking part in a survey to share their local knowledge about seagrass and fishing areas. This information is helping identify the best sites for future seagrass restoration work. Full results will be released in the New Year, but early insights already show just how valuable local experience is in guiding conservation. If you’d like to take part, the survey is open until 31st January link here: https://t.ly/gxUSx What’s next? Project Seagrass will also be hosting a series of events in the New Year to celebrate sustainable local seafood and the amazing role seagrass plays in healthy seas. This work is made possible thanks to funding from the Nature Networks Programme which is being delivered by the National Lottery Heritage Fund on behalf of Welsh Government, and Rebel Restoration.
Grammy-nominated singer and Solent Seascape Project collaborate with Jeremy Irons and Angela Harding to celebrate and protect the region’s coastal habitats. The Solent Seascape Project, of which Project Seagrass is a partner, has launched Songs from the Solent, a new EP by Grammy-nominated singer and songwriter Richard Walters that uses music to spotlight the Solent’s threatened coastal habitats and the communities connected to them. Created during Richard’s Artist Residency with the project, the album is inspired by the Solent’s local community as well as the saltmarshes, seagrass meadows, oyster reefs, and seabird sites the project is working to restore and protect – habitats that lock away carbon, protect shorelines, and underpin marine life. Available to stream and download now, the album features eight original songs influenced by the sounds of the seascape and voices of the Solent, with proceeds helping towards vital restoration of these threatened habitats. “I hope the songs I’ve written shine a light on parts of the coastline it’s easy to overlook, I hope they make people think about this seascape and why we must give it our care and attention, and I really hope it inspires people to spend time exploring the area,” Richard said. Local stories, international voices The album brings together a rich tapestry of local Solent talent, including painters, choirs, and musicians, alongside internationally acclaimed contributors. Oscar-winning actor Jeremy Irons, who was born on the shores of the Solent at Cowes on the Isle of Wight, lends his distinctive voice to Lanterns Part 1; Isle of Wight artist Trudie Wilson lists the paints made of natural pigments she uses in the song Wight Paint; and members of Big Notes Choir from Chichester sing on Salt Forests, inspired by the tiny wonders of saltmarsh worlds. Richard said, “To be awarded this residency has been a real gift, an excuse to get out there and dig a little deeper, to meet the people that play their part in Solent communities, to tell their stories and give voice to the silent elements in need of our support. The work the Solent Seascape Project does is remarkable and I’m very happy to play a small part in amplifying their message.” To gain inspiration for the songs, Richard met with local groups and communities to find out what makes the Solent and its habitats special to them. It saw him chatting with sea swimmers at Hayling Island and heading to the top of Spinnaker Tower in Portsmouth. Their responses have been woven together with field recordings gathered at sites the project is working to restore. Adding a visual dimension to the release, renowned linocut artist Angela Harding has created a bespoke map of the Solent. The map highlights the locations that inspired each song and features on the Solent Seascape Project’s website, allowing listeners to connect the music directly with the places that shaped it. “It has been a great delight to work on this special map of the Solent Seascape Project for Richard Walters. It is loosely based on an old sea chart — with wild winds pushing the terns to their rafts, and Richard sailing out to sea in a small boat, cat and guitar, dodging sea monsters as he goes. I hope it is a map to be enjoyed and raise awareness of the important conservation work being done by the Solent Seascape Project,” said Angela. A seascape in recovery The Solent Seascape Project is a five year, multi-million-pound partnership of 10 organisations led by Blue Marine Foundation, working to protect, restore, and reconnect key habitats – saltmarsh, seagrass, seabird nesting sites and native oyster reefs – across the Solent. Through music, Songs from the Solent aims to raise awareness of the environmental challenges facing these habitats while building a deeper, emotional bond between people and place. Solent Project Manager, Louise MacCallum said, “The Songs from the Solent have given me the opportunity to look at this beautiful seascape we are working to restore through such a wonderful new artistic lens. I feel excited for new members of the Solent community to discover the work we are doing through the power of music.” The songs area available to download and stream on Spotify, Apple Music, Amazon Music and Bandcamp, with a live performance taking place at the Square Tower in Portsmouth on 11 February. Tickets for the performance will be free and are available from Friday (16 Jan). The Solent Seascape Project is supported by East Head Impact and the Endangered Landscapes & Seascapes Programme (ELSP), managed by the Cambridge Conservation Initiative and funded by Arcadia. Find out more about the Solent Seascape Project at www.solentseascape.com
Grace Cutler, one of our 2025-26 Project Seagrass interns, reflects on Rebekah Bajkó’s research, Coastal Roots: The History of Seagrass in Northern Ireland. Northern Irish Seagrass In November 2025, I attended the UK Seagrass Symposium, an exciting conference hosted every two years to highlight the current state of seagrass research within the UK. It was an incredible event that inspired hope and determination, alongside furthering my own caffeine addiction. However, there was one talk in particular, delivered on the first day, that stuck with me for the remainder of the conference, delivered by the researcher Rebekah Bajkó. It was during the ‘Anthropogenic pressure and Environmental drivers of seagrass decline’ segment where Bajkó explored the history of seagrass in Northern Ireland. Here, they highlighted a critical issue that had been wriggling at the back of my mind since my journey into seagrass research began. Where is all the Northern Irish Seagrass? A History of Seagrass It turns out, seagrass has been on our doorstep for a long time. The first record of the common eelgrass (Zostera marina) date back to the 18th century where it grew in such abundance, beaches were described as having a ‘greenish tinge’, carpeting the likes of Belfast Lough with grassy gold. And it’s not just seagrass researchers that view it this way. A letter from a man known as A. MacDougall wrote to the Chief Secretary, William lamb, in 1829, inquiring after a patent for the manufacturing of Seagrass (who intended to use it as mattress stuffing). It wasn’t just humans that sort after these meadows. Brent geese (Branta bernicla), which are known for travelling to Strangford Lough, would feed on the eelgrass across the country. The coastlines also used to contain small populations of Hippocampus hippocampus, the short-snouted seahorse, which still remains as a symbol of Belfast on the city’s crest (Belfast City Hall, n.c). Their appearance in our waters coincide with the period of time when seagrass meadows were at their healthiest. There comes a sense of pride with having such interesting species and habitats next to our homes. Much to my own surprise, my home village (Dundrum, Co. Down) was the first-time dwarf eelgrass (Zostera Noltii) was discovered in Northern Ireland, in 1914. Dundrum, Northern Ireland, Photo taken by Grace Cutler Yet, despite their abundance and importance for life in Northern Ireland, in the late 19th century, seagrasses began to decline. Much like the rest of the UK, it is believed with increasing anthropogenic stressors, such as land-use change and nutrient input, seagrass became less resilient. This left it open to the seagrass wasting disease. The lack of seagrass in Northern Ireland has since been felt by those living on coastlines since its initial decline. Particularly, in Belfast, without the wave attenuation seagrass provided, waves break on beaches causing rapid degradations of its shorelines. Furthermore, the loss of seagrass has been felt by birders, who noticed a decline in avian species, and called for an investigation during the early stage of seagrass decline. What is Left? Since the 1940s, there has been a small recovery seen in seagrass species. Although seagrass has completely disappeared from Belfast Lough it remains in Strangford Lough and is dotted throughout the country. Records of seagrass (1794-1994) layered with the extent of seagrass in 2023 across the Northern Irish coast. Map lines show study areas and not necessarily national boundaries (Bajkó, R., Millar, R., & Smyth, D., 2025) So why is there so little seagrass along Northern Irish coastlines? Currently, there are no active restoration programmes aiming to restore seagrass in Northern Ireland. Belfast Lough has not seen seagrass for over 60 years and is unlikely to in its current state. Strangford Lough on the other hand has great potential for recovery and has already experienced natural recovery of Zostera marina and has the largest extent of Zostera noltii across the whole island. Seagrass researchers like Rebekah Bajkó and Heidi McIlvenny (a PhD student who focuses on assessing the sediment organic stocks in Northern Irish seagrass meadows) are beginning this conversation. If you are interested in any of the information mentioned here, I highly recommend reading Bajkó’s, original paper which goes into much greater detail on this subject. Yet, more attention needs to be brought to Northern Ireland so we can see substantial increases in seagrass meadows. Until then, they may forever remain our forgotten meadows. References Bajkó, R., Millar, R., & Smyth, D. (2025). “Coastal roots: the history of seagrass in Northern Ireland.” Journal of the Marine Biological Association of the United Kingdom, 105, Article e63. https://doi.org/10.1017/S0025315425100106. Belfast City Hall (no date). “History of Belfast city hall.” Available at: https://www.belfastcity.gov.uk/things-to-do/city-hall/history-of-belfast-city-hall. (Accessed: 8 January 2026)
Current estimates of the global extent of seagrass range from between 160,000-266,000km. Such a high degree of uncertainty presents challenges for researchers and managers and their ability to make informed decisions which account for the changing status of seagrass ecosystems. Key to improving our understanding of seagrass presence and absence, identified as one of the six Global Challenges facing effective seagrass conservation, is the collection and integration of interoperable data on seagrass extent. A new paper published in Bioscience from members of the Coordinated Global Research Assessment of Seagrass Systems working group outlines how the Seagrass Essential Ocean Variable can help us to address this challenge. This paper was co-written by members of our Project Seagrass team. Achieving our goals for seagrass conservation requires reliable information on the status and trends of seagrasses and the organisms that associate with them, yet seagrass variables measured and the methods for doing so vary widely across projects and organisations, presenting challenges for comparisons across studies. This new paper provides a global framework for seagrass monitoring as an Essential Ocean Variable of the Global Ocean Observing System, key to aligning seagrass researchers and managers around a common approach to seagrass monitoring. Implementing these guidelines will support the collection of more comparable, compatible, and combinable seagrass data. The Seagrass Essential Ocean Variable contains three priority measurements to maximise compatibility across data sets: Seagrass percentage cover Seagrass species composition (the identify and relative abundances of seagrass species in an area) Seagrass areal extent (the horizontal extent of seagrass at the meadow of seascape scale These three priority measurements collectively have been identified to provide the most useful assessment of seagrass status and change at landscape scales, addressing most scientific, management, and policy needs and targets. The Essential Ocean Variable also includes further supporting variables relating to biological and environment factors. Seagrass monitoring using SeagrassSpotter At Project Seagrass we’re well placed to contribute to this global process with our OpenAccess SeagrassSpotter.org platform collecting georeferenced data on seagrass percentage cover and species composition. In 2026 we will also be launching a complementary app called SeagrassTracker which will help scientists report, share, and archive data on seagrass spatial extent. These platforms are all linked to the Global Ocean Observing System. Key to the Seagrass Essential Ocean Variable is a commitment to collaborate. If utilised across widely, the EOV will support the creation of a growing resource of seagrass data that is maximally compatible and supports more reliable local research and better-informed management.
