Marine experts have expressed delight over positive signs that thousands of oysters released into the Firth of Forth are settling in well to their new environment.

Heriot-Watt University, one of a group of organisations involved in a project to reintroduce European flat oysters to the estuary, recently led monitoring sessions with divers and underwater camera equipment to check on their status.

Oysters have been absent from the Firth of Forth for nearly 100 years and so far those reintroduced to the area through the Restoration Forth project have had an 85% survival rate.

Around 30,000 oysters have been released into the estuary since September last year, with monitoring taking place at four restoration sites to track their progress.

Edinburgh Shoreline, Fife Coast and Countryside Trust, the Marine Conservation Society, Project Seagrass and the WWF are among the numerous organisations involved in the project.

Crab ans oysters on the seabed
The oysters were reintroduced last year (Heriot Watt Dive Team/PA)

Bill Sanderson, professor of marine biodiversity at Heriot-Watt, said: “From its inception, Restoration Forth has taken careful steps to find the best places to restore oysters to the Firth of Forth.

“We are delighted that their high survival so far reflects the painstaking efforts we have made to support this initiative.”

Naomi Kennon, a Heriot-Watt research associate for the project, said: “We have worked with hundreds of people from around the Forth to clean and move oysters to their new home.

“Working with the volunteers, over the next year we hope to see these oysters continue to thrive and to start to enhance the biodiversity on the seabed.

“Our project will not only bring back a native species lost to overfishing in the 1800s, but also the ecosystem services those animals bring with them.

“Oysters enhance water quality through filter feeding, store carbon and enhance biodiversity by creating a complex habitat providing homes and shelter for countless other organisms.”

Two women on a boat throwing oysters into the sea
Around 30,000 oysters have been released in the area since September 2023 (Maverick photo agency/PA)

Anna Inman, shellfish engagement officer at the Marine Conservation Society, said: “The community support for oyster restoration has been incredible.

“We truly appreciate all the hard work that has gone into bringing oysters back to the Firth of Forth.

“This achievement is a testament to the dedication of all the volunteers who have generously given their time.

“The project not only aims to revive marine life but also highlights the cultural heritage of oysters and emphasises our collective responsibility to restore and protect our seas for future generations.”

Naomi Arnold, Restoration Forth project manager from WWF Scotland, said: “We’re delighted by the early signs of success.

“This is down to the hard work of not only the staff involved, but the hundreds of volunteers who have turned out in all weathers to help us prepare the oysters for deployment, and to physically put them in the water.

“This is a key milestone in our project, with this success and the amount we have learned, things are looking very positive for future restoration in the area.”