Seagrass protection and recovery
Find out why seagrass is important, how to avoid damaging seagrass beds and how the Marine Management Organisation (MMO) supports seagrass protection and recovery in England.
About seagrass
Seagrass is a flowering plant that grows in shallow coastal waters. It can form underwater meadows that provide nursery and feeding habitat for fish, shellfish and other wildlife, including seahorses.
Healthy seagrass beds can also help stabilise sediment, reduce wave energy, improve water quality and store carbon.
Once found widespread across the UK, our seagrass beds have declined by over 40% since the 1930s. This is mainly due to coastal development, pollution and wasting disease, as well as physical disturbance.
Seagrass form beds, or meadows, in shallow coastal areas (intertidal and subtidal regions) where they receive plenty of light. They also prefer sheltered bays and lagoons protected from significant wave action.
There are two recognised species of seagrass in the UK:
Common eelgrass (Zostera marina)
Found in deeper water (intertidal to sublittoral region), in fully submerged conditions to about 10 meters deep, typically on sand, mud or course gravel. It is the largest British seagrass and forms dense beds, with trailing leaves up to 2 meters long.
Dwarf eelgrass (Zostera noltii)
Found closer to the shore (intertidal to shallow subtidal region) on fine sand and mud. It forms dense beds, with leaves up to 20cm long.
Both species grow horizontal stems (rhizomes) which spread under the substrate, rooting it firmly to the seabed. It also has air pockets (lacunae) in the veins of its leaves to help the seagrass blades float in an upright position in the water.
Watch this short clip to see what life can be found in a seagrass meadow: Seagrass video.
The value of the UK’s underwater meadows - Ecosystem services
Seagrass is one of the most valuable coastal ecosystems and provides a range of ecosystem services.
An ecosystem service is a way in which nature (natural capital) contributes to human existence, wellbeing and quality of life. Seagrass beds contribute to the maintenance of fish and shellfish populations providing stock for our seafood industry. This ecosystem service subsequently brings benefits to society, through food, nutrition and employment. Other ecosystem services include:
A safe and diverse habitat
As its name suggests when thriving, seagrass can form underwater meadows of swaying grass fronds, providing a safe habitat for a huge diversity of life, hiding juvenile fish, crustaceans and seahorses. Seagrass meadows are a nursery and feeding ground for fish and invertebrates improving biodiversity, increasing population density and supporting commercial fisheries.
Coastal protection
Seagrass beds provide an important service to coastal communities through coastal protection. The rhizomes stabilise sediment that helps prevent erosion. The leaves also slow down currents and absorb wave energy that buffers the impact of storms and waves. Seagrass also improves water quality, acting as a filter for low-levels of pollutants and nutrient runoff.
Carbon storage
Seagrass plays a significant role in global carbon storage and the potential mitigation of climate change. It is responsible for over 10% of the buried organic carbon in the ocean. When seagrass photosynthesises it takes carbon from the atmosphere and stores it in its leaves. When the plant dies, this carbon is buried and stored in the sediment.
Carbon is also captured in the form of organic material within the base of seagrass blades and locked in the sediment. This is known as ‘blue carbon’. The loss of seagrass beds leads to the loss of their carbon sink capacity, and potentially the release of carbon previously stored in their sediments.
Tourism and wellbeing
As seagrass meadows occur in shallow water or intertidal areas, they create tourism hot spots for wildlife watching and watersport enthusiasts such as swimmers and snorkelers.
Download the ReMEDIES seagrass infographic to learn more.
MMOs role
MMO assesses and manages the effects of marine non licensable activities on marine protected areas within 12 nautical miles of the English coast. This includes sites where seagrass is a protected feature.
Where evidence shows that management is needed, MMO can use proportionate measures including information and education, voluntary approaches and statutory measures.
Risks to seagrass
Seagrass is delicate and can be easily damaged by traditional moorings, and the dropping and weighing of boat anchors, which can drag along the seabed, expose the roots, leave large anchor scars, fragment the habitat and permanently damage the seagrass beds beyond recovery. It can be damaged by marine recreational activities such as launching of leisure boats, as well as other shore and water-based activities.
Excessive nutrient runoff into the sea from farms (agricultural fertilisers) and waste water from urban areas, can cause algae growth (eutrophication) and increase sediment in areas where seagrass is found. This can smother seagrass by reducing availability of light.
Increased ocean temperatures, ocean acidification and large storm events, as a result of climate change, also have a detrimental effect on seagrass.
Direct damage can result from dredging for coastal development.
How to protect seagrass
If you use coastal waters where seagrass is present:
- Check available navigation and habitat information before anchoring
- Avoid anchoring on seagrass where it is safe to do so
- Use an advanced mooring system or ecomooring where one is available and suitable. Advanced mooring systems, sometimes called ecomoorings, are designed to reduce contact with the seabed compared with traditional moorings. The right system depends on local conditions and the vessel using it.
- Follow voluntary no anchor zones
- Avoid entering or leaving the water through intertidal seagrass beds where possible
- If you dive or snorkel in seagrass or a known seahorse location, follow MMOs seagrass and seahorse diving guidance. Avoid disturbing animals or damaging their habitat
Both species of seahorse native to the UK are protected by law. You may need a wildlife licence if you intend to carry out an activity that is likely to disturb seahorses or damage their habitat. [Understand and apply for marine wildlife licences]](https://www.gov.uk/guidance/understand-marine-wildlife-licences-and-report-an-incident)
Supporting seagrass recovery and restoration
Protecting existing seagrass and reducing the pressures that caused damage should be considered before restoration work begins. Depending on the site, this can include managing recreation, providing alternatives to anchoring, replacing traditional moorings, improving water quality and reducing impacts from development or fishing activity.
Consents and licences
Collecting seagrass or plants, depositing material, installing restoration equipment or carrying out other works may require a marine licence, wildlife licence or advice from Natural England.
It is an offence under section 140 of the Marine and Coastal Access Act 2009 to intentionally pick, collect, cut, uproot or destroy, any plant in a Marine Conservation Zone (MCZ) which is a protected feature of that MCZ. Natural England advise that anyone with plans to collect seagrass seeds or plants should liaise with Natural England on methods and suitable locations prior to this collection, to enable projects to progress swiftly without hindering recovery of designated seagrass beds and to avoid committing an offence.
Additionally, as a wild flowering plant, the removal or uprooting of seagrass plants is prohibited under Section 13(1)(b) under the Wildlife & Countryside Act 1981. Please seek advice from Natural England in this case.
MMO Marine Licence
It is your responsibility, as the applicant, to determine if you require a marine licence for activities in the marine environment: Do I need a marine licence? Please see our website for further information on the marine licensing process, timescales and any associated fees: Make a marine licence application.
MMO Wildlife Licence
Section 9 of the Wildlife and Countryside Act 1981 protects both species of seahorse native to the UK: spiny or long-snouted seahorse (Hippocampus guttulatus) and short snouted seahorse (Hippocampus hippocampus). You must have a wildlife licence if you are diving or snorkelling and intending to do something likely to disturb seahorses, or damage the habitat they live in. This could be diving in a known seahorse location, taking photographs, filming seahorses or removing seagrass.
Further advice on restoring seagrass:
- Restoration Handbooks published to give best practice advice on creating new estuarine and coastal habitats
- Seagrass Restoration Handbook - CaBA (catchmentbasedapproach.org)
- ReMEDIES Seagrass Cultivation & Restoration Best Practice Guide
Seagrass restoration - best practice case studies
ReMEDIES
ReMEDIES stands for Reducing and Mitigating Erosion and Disturbance Impacts Effecting the Seabed.
The LIFE Recreation ReMEDIES project focused on how sensitive seabed habitats are impacted by recreational activities and provides a number of case studies which demonstrate how varied management measures can be effective. It aimed to reduce recreational pressure, restore seagrass habitats and promote awareness.
The project installed advance mooring systems (AMS) to protect the seagrass, and implemented Voluntary No Anchor Zones (VNAZ) to manage access to seagrass beds. The Royal Yachting Association (RYA) Green Blue Project advises best practice for recreational boating providing the Green Guide to Anchoring and Moorings to help minimise disturbance, and identifying UK seagrass bed locations to inform boaters of where to be more vigilant when considering an anchor spot.
Active restoration was key to the ReMEDIES project. The Ocean Conservation Trust planted a total of eight hectares of seagrass meadows within two Special Areas of Conservation (SAC).
Ocean Conservation Trust
The Ocean Conservation Trust exists to protect and restore the ocean. Their vision is a world where the ocean is thriving, healthy, and sustainably protected for generations to come. The Ocean Conservation Trust’s Blue Meadows project is a holistic approach to seagrass protection, regeneration and restoration at scale.
The goal is to protect the seagrass we already have, and over the longer-term restore the seagrass we have lost. ‘Blue Meadows’ places local communities at the heart of its work through community engagement, enabling coastal communities to feel inspired and empowered to help protect their local seagrass meadows and equipping them with the resources to do so.
The Ocean Conservation Trust have developed an immersive experience, so everyone can explore the wonders of seagrass, no matter their age or where they live.