Seagrass protection and recovery

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:

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.

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.