The new Great Seagrass Survey, the first of its kind in the UK, is a collaboration between Scottish charity, Seawilding and the British Sub Aqua Club (BSAC). During its inaugural event in May 2023, a team of volunteers scuba dived, snorkelled and strolled the coastline, searching for evidence of seagrass and logging their results.

“The biggest surprise was how much seagrass was found. Most of the beds they discovered aren’t included in official records and could have been undiscovered for centuries so this is ground-breaking stuff,” said project organiser Katherine Knight, Science and Survey Officer at Seawilding.

Seagrass meadows have been described as the most valuable coastal and marine ecosystems on the planet. Despite their benefits, seagrass habitats are under threat from a variety of factors. It is estimated that beds have declined by an estimated 92% over the past 100 years within the UK as a result of physical disturbance and pollution issues. Worldwide, an area of seagrass the size of a football pitch (0.8 hectares) is being destroyed every 30 minutes.

As primary producers, however, seagrasses form diverse homes for a variety of the UK’s most important commercial and rare marine species, such as seahorses. Seagrass meadows have further been identified as crucial allies in the fight against climate change as they emit oxygen, and remove carbon and lock it in the sediment.

Thanks to the Great Seagrass Survey volunteers, a total of 96 beds were mapped around the country, from the Outer Hebrides to the Channel Islands.  Both of the two species of seagrass found in UK waters were recorded; Zostera noltei which can be found on the beach at low tide and Zostera marina which is found in shallow waters. The largest area mapped was 78 hectares by the Moray Ocean Community near Inverness.

“By knowing where seagrass is, more can be learnt about the threats it is facing as well as what is required to conserve it,” added Knight.

Volunteers were able to upload their discoveries onto the BSAC website where the information was then analysed, collated and shared by Seawilding with national databases making it accessible to scientists and policy makers.

“Seagrass is notoriously hard to restore once it is lost, so these new beds are incredibly valuable for both biodiversity and carbon capture,” said Danny Renton, CEO of Seawilding. “We hope that these patches of endangered and unmapped seagrass – and the ones that the survey will reveal in the future – can be the cornerstone of new restoration projects inspired and driven by coastal communities.”

The Great Seagrass Survey will be taking place again this year. To find out how to get involved click here.

For more from our Ocean Newsroom, click here.