• Name: Common Eelgrass | Zostera marina
  • Size: 1.2 cm wide and may reach over 1 metre long
  • Life span: Eelgrass is a perennial plant (lives for more than two years), but it may grow as an annual (completing its life cycle within one growing season)  
  • Diet: Sunshine (being a plant it uses photosynthesis to produce food)
  • Reproduction: Seagrass reproduces vegetatively, i.e. by the growth of rhizome and also through seeds
  • When to see: Throughout the year (January to December)
  • Where to see: Sheltered bays and beaches i.e. Town Beach/Harbour, St Mary's | Higher Town Bay, St Martins | Carn Near, Tresco in Scilly.  (Help us with mapping by logging your finds via the Seagrass Spotter App!) 
  • Conservation status: ICUN Redlist | Least Concern.
  • Population Trend: Decreasing
  • Threats:  Human activity (i.e. dredging, trawling, anchoring/mooring boats), pollution, climate change (changes in weather patterns, changing sea temperatures). 
  • Fun Fact: Seagrass can absorb carbon up to 35x faster than Amazonian rainforest!

Description: Common Eelgrass is a flowering plant, not a seaweed (despite growing under the sea), and as the name suggests is grass-like in appearance; having green, long, ribbon-shaped leaves with rounded tips. 

The visible green ribbons grow from a creeping rhizome (mat-like roots that hold-fast) binding the fine gravel and sand beneath the leaves, allowing the formation of large underwater Eelgrass meadows in sheltered bays and inlets.

Eelgrass meadows (or beds) support a diverse range of other flora and fauna, acting as a nursery for fish and shellfish.

Globally, estimates suggest we lose an area of Seagrass around the same size as two football pitches every hour!

Want to know more?  Check out our blog "Scilly's Magical Meadows".


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With thanks to Paul Naylor for the Underwater Eelgrass bed image