SoNaRR 2025: Coastal margins

The coastal margins ecosystem consists of the habitats around the coastline of Wales. The three most extensive habitats are sand dunes, saltmarsh, and sea cliffs. Others are saline or coastal lagoons and shingle.

Key messages

• Coastal habitats provide unique biodiversity and valuable services, including flood defence, blue carbon, recreation, and health. These services could be developed as nature-based solutions for the people and economy of Wales through habitat restoration and enhancement.
• Habitat loss and fragmentation, poor condition and loss of biodiversity are affecting coastal habitats. The main causes include non-sustainable agricultural management, invasive non-native species and air and water pollution.
• Climate change will lead to increasing pressures including sea level rise and higher rates of erosion. Some habitats are naturally able to roll-back inland, responding to change, but in many cases the coastal habitats are hemmed in by other land use.
• Recent work on sand dunes demonstrated successful landscape scale restoration of dune systems across Wales. We now need restoration programmes for saltmarsh and sea cliff habitats which will benefit biodiversity and increase resilience, carbon sequestration and natural flood alleviation.
• Many pressures, including climate change and water quality, require a strategic and multi-faceted approach to improve ecosystem resilience. Key opportunities include land use planning, tackling multiple sources of pollution and maximising outcomes from the Sustainable Farming Scheme.
  
  

Assessment of SMNR

This coastal margins assessment is one of eight ecosystem and three natural resource assessments that inform the overall SoNaRR2025 report. It builds on the findings of SoNaRR2020, drawing together updated evidence from subject experts, national datasets, and collaborative projects such as Sands of LIFE and Dynamic Dunescapes. This assessment is closely linked to the marine and enclosed farmland ecosystem assessments.

The assessment is structured around four interlinked aims that guide Wales’s progress toward the sustainable management of natural resources (SMNR), helping to communicate the relationship between the environment, well-being, and the economy.

Aim 1: Stocks of natural resources are safeguarded and enhanced

Biodiversity in coastal margin ecosystems is declining, with several species now extinct in Wales, including the Oysterplant and Belted beauty moth. Many species are restricted to single localities or specific habitats, such as the Large mason bee and Foxtail stonewort. Others, like Shore dock and Fen orchid, are in unfavourable condition due to habitat degradation. Invasive Non-Native Species (INNS), pests, and diseases continue to impact native biodiversity. Despite eradication efforts under projects like Sands of LIFE, INNS remain widespread, with climate change likely to exacerbate these impacts. Meanwhile, diseases such as Myxomatosis, Rabbit Haemorrhagic Disease and Avian Influenza have caused population declines in rabbits (important for the maintenance of sand dune habitats) and seabirds.

Air, water, and soil pollution also threaten coastal margins. Nitrogen deposition exceeds safe levels in dunes, sea cliffs and saltmarsh, which can alter vegetation and reduce habitat quality. Water pollution from nutrients, contaminants, and marine litter persists, with saltmarshes and lagoons being particularly vulnerable. Historic landfill sites near the coast pose ongoing risks with rising sea levels. Soil pollution trends are deteriorating, and climate-related changes—like increased storminess and sea level rise—are expected to intensify these pressures. Projects such as Sands of LIFE, Dynamic Dunescapes, Connecting the Coast and Tir a Môr Llŷn have gone some way to restore habitats and improve species conditions, demonstrating positive steps toward safeguarding natural resources within the coastal margins ecosystem.

Aim 2: Ecosystems are Resilient to Expected and Unforeseen Change

Coastal margin ecosystems show medium resilience overall, but pressures are causing deterioration in diversity, extent, condition, and connectivity. Diversity is declining in sand dunes, saltmarshes, and sea cliffs due to over and under-grazing, stabilisation, and pollution. Coastal lagoons face species loss and community shifts. While some habitats benefit from active management, others lack sufficient intervention. Future resilience is uncertain, with climate change, tourism, and invasive species posing ongoing threats. The new Sustainable Farming Scheme may offer improvements, but confidence remains low.

Extent is generally stable but has deteriorated historically due to development, erosion, and historic afforestation. Sea level rise and coastal squeeze threaten future habitat loss, especially for saltmarshes and dunes. Condition is assessed as low across all habitats, with pollution, over grazing and under-grazing and vegetation succession contributing to poor condition. Connectivity is also low, with fragmentation from agriculture and development. Restoration projects have improved local connectivity, but future trends suggest further deterioration without sustained action. Projects like Sands of LIFE, Dynamic Dunescapes and Connecting the Coast have enhanced resilience through targeted habitat restoration and improved land management.

Aim 3: Healthy Places for people, protected from environmental risk

Coastal margin ecosystems provide vital services that protect human health. Saltmarshes and dunes reduce flood risk and store carbon, helping mitigate climate change. Welsh saltmarshes sequester over 7,700 tonnes of carbon annually. These habitats also filter air pollutants, removing 850,000 kg in 2023, and purify water by absorbing nutrients and heavy metals. Pollination services from dunes and saltmarshes support crop production and biodiversity. Waste remediation and water purification further enhance environmental quality and reduce treatment costs.

These ecosystems also support health improvement through recreation and cultural services. There were over 21 million visits to coastal margins in 2021/22, generating £70 million in health benefits. Projects like Sands of LIFE contribute £26 million annually to local economies and support hundreds of jobs. Coastal areas offer spiritual and educational value, with saltmarshes and sand dunes inspiring art and research. Despite socio-economic deprivation in some coastal towns, the physical environment remains a source of well-being. Initiatives like CoastSnap and shoreline adaptation planning are engaging communities and improving access to nature-based solutions.

Aim 4: Contributing to a Regenerative Economy, Achieving Sustainable Levels of Production and Consumption

Coastal margin ecosystems support economic resilience through natural flood protection, water purification, and high-value agricultural products. Saltmarshes protect 2,000 ha of farmland and reduce nutrient pollution. Grazing on saltmarshes and dunes produces premium meat, while rare livestock breeds and plant seeds contribute valuable genetic resources. Sustainable agriculture, when appropriately managed, enhances biodiversity and carbon sequestration. However, overgrazing and historic afforestation continue to degrade habitats, and future trends depend on effective implementation of schemes like the new Sustainable Farming Scheme.

Tourism and recreation offer economic opportunities but also pose pressures through trampling and littering. Coastal development and flood defence infrastructure contribute to habitat loss and fragmentation. Nature-based solutions, such as saltmarsh restoration, offer co-benefits for climate adaptation and ecosystem regeneration. Projects like Ffermio Bro and Pembrokeshire Heathland Beef demonstrate how collaborative farming can support biodiversity and community engagement. With 42 million recreational visits annually, sustainable tourism has the potential to fund ecosystem restoration and build resilience, if managed responsibly.

Key changes since SoNaRR2020

Since SoNaRR 2020, new evidence from vegetation mapping of shingle, selected sand dunes, and saltmarshes has improved our knowledge base supporting coastal habitat management. These new data are improving understanding of erosion and accretion dynamics and informing future management. A new report on coastal squeeze has modelled its extent around the Welsh coast, alongside additional reports examining climate change impacts on coastal habitats.

The Nature Networks Programme, launched in 2021, has delivered targeted habitat management on statutory sites, improving the condition and connectivity of protected areas and supporting more resilient ecological networks. Invasive Non-Native Species control has also been strengthened, particularly on sand dune sites, through the Sands of LIFE AfterLIFE project and Nature Networks funding. Despite these positive developments, nitrogen and ammonia deposition pressures remain critically high, posing an ongoing threat to coastal margin habitats. The Sustainable Farming Scheme, launching in 2026, offers a promising opportunity to bring more coastal habitats into positive management.

Read the full assessment of the Coastal margins ecosystem in our State of Natural Resources Report 2025.

Underlying evidence

In writing our assessments and to better identify opportunities for action we have gathered evidence that helps us understand these key aspects:

• the drivers of change and pressures on coastal margins in Wales.
• the ecosystem resilience of coastal margins in Wales.
• the benefits, or services, we get from coastal margins and how changes in the state of coastal margins impact on well-being.

Access the detailed evidence through our SoNaRR 2025 Evidence portal.

View full screen version

Evidence needs

A wide range of evidence needs has been identified to support the sustainable management of Wales’s coastal margins. These include updated data on the extent and condition of key habitats such as sand dunes, saltmarshes, sea cliffs, shingle, and lagoons, along with improved understanding of habitat change and resilience. Climate change impacts are a major concern, with evidence needed on habitat rollback, sediment budgets, and the effects of changing temperature and rainfall patterns on coastal systems.

Further research is required to understand the ecosystem services provided by coastal margins, including the role of saltmarshes in supporting fish populations, flood protection, and nature-based solutions. The impact of human pressures such as agriculture and recreation also requires further investigation. Restoration and connectivity opportunities should be identified to reverse habitat fragmentation. Finally, long-term impacts of chemical and nutrient pollution on coastal ecosystems remain a critical evidence gap, particularly in relation to saltmarsh.

Read SoNaRR 2025 Evidence needs.

Key evidence sources

Explore some of the evidence we have used to inform our assessment:

• SoNaRR 2020 Coastal Margins Assessment
• Condition assessments for Welsh European marine sites
• First Habitats Regulations 9A Report for Wales 2025
• Flood and Coastal Erosion Risk Maps (naturalresources.wales)
• Marine Climate Change Impact Partnership science reviews
• NRW Marine and Coastal Evidence Reports 
• Sands of LIFE Project
• People and Nature Survey for Wales
• UK Natural Capital Accounts
  
  

Case studies

Connecting the Coast project

Pembrokeshire Coastal Park's 'Connecting the Coast' project funded by the Nature Networks was a land management scheme which offers funding for the creation and maintenance of wildlife habitats along Pembrokeshire’s coastline. The project provides payments for capital works for management of coastal grasslands and heathlands but also includes other habitats such as neutral grasslands in the vicinity of the coast.

Connecting the coast - Landscapes Wales

Tir a Môr

The ‘Tir a Môr Llŷn’ project undertook and delivered a programme of land management interventions to improve the connectivity and resilience of the coastal strip on Pen Llŷn. This included changes in grazing regimes to enable plants to flower and set seed and introducing fencing and a water supply to enable cattle to graze the coastal slope.  The Tir a Môr scheme, offered payments for outcomes for habitats and species, much of this was within habitats on the coastal slopes. The 3 farms in the scheme all showed nature positive improvements and informing numerous stakeholders on the scope and potential of payments for outcomes projects.

Tir a Môr | Pen Llŷn a’r Sarnau

Sands of LIFE and Dynamic Dunescapes projects

The Sands of LIFE and Dynamic Dunescapes projects continued until 2024. These projects continue to provide benefit to the coastal margin ecosystems (sand dunes particularly). Habitat has been restored by creating dynamic conditions via mechanical means, removing scrub, tackling INNS, installing or enhancing grazing infrastructure, felling conifers and creating early successional habitat.

Natural Resources Wales / Sands of LIFE

Dynamic Dunescapes