Common eelgrass

Common eelgrass

Scientific name: Zostera marina
This seagrass species is a kind of flowering plant that lives beneath the sea, providing an important habitat for many rare and wonderful species.

Species information


Leaf: Usually 20-50cm long

Conservation status

Seagrass beds are Priority Habitat under the UK Post-2010 Biodiversity Framework and a Feature of Conservation Importance for which Marine Conservation Zones can be designated. They are on the OSPAR List of Threatened and/or Declining Species and Habitats (declining in Region II – North Sea and Region III – Celtic Sea, and threatened in Region V – Wider Atlantic).

When to see

January to December


Common eelgrass is a plant species (not a seaweed) that lives on the very low shore down to 10m deep and can form dense seagrass meadows. These meadows form important underwater habitats in shallow seas, providing shelter for many species, including seahorses and pipefish. They also provide important nursery habitats for small fish, cuttlefish, shellfish and rays. Seagrass beds grow on sandy seabeds in very shallow waters - as they need good levels of light to photosynthesise. They grow in sheltered areas, such as estuaries, bays and inlets. Seagrass is an important food source for many overwintering birds such as geese. Common Eelgrass gets its name from its long, eel-like leaves.

How to identify

Unmistakeable - an underwater grass-like plant, with long thin green leaves. Sometimes found washed ashore after storms.


A wide but patchy distribution around the UK.

Did you know?

Seagrass is one of very few true plants that live in the sea. (Seaweed is a type of algae, not a plant!) eelgrass is a flowering plant - producing numerous flowers and ultimately producing seeds. They also have a Rhizome - a type of underground root system that allows new plants to grow vegetatively.

How people can help

Protecting fragile seagrass beds from damaging activities is needed to ensure the habitat itself and the species that rely on it are safeguarded for the future. The designation of Marine Protected Areas is proven to benefit vulnerable seabed habitats and species when damaging activities are prohibited. The Wildlife Trusts are campaigning for the designation of Marine Conservation Zones to protect seagrass beds and other seabed habitats. You can support our campaign by becoming a Friend of Marine Conservation Zones at All around the UK, Wildlife Trusts are working with sea users, researchers, politicians and local people towards a vision of Living Seas where marine wildlife thrives. Do your bit for Living Seas by supporting your local Wildlife Trust or check out our Action pages.