DIVERS have placed 20,000 native oysters in the sea in a bid to restore native reefs which were fished to extinction more than 100 years ago.

Last year saw oysters return to the Dornoch Firth for the first time in more than 100 years when researchers placed 300 from the UK’s only sizeable wild population in Loch Ryan on two sites in the by the Glenmorangie distillery in Tain.

The distillery wants to restore the long-lost oyster reefs to the Firth to work in tandem with a new digestion plant to purify the by-products created through the distillation process and keep the waters clean.

Now for the second phase of the project, they are aiming to recreate entire reefs which is the very first time this has been attempted anywhere in Europe.

The native oysters, all grown in the UK, were cleaned and checked for disease and will be regularly monitored.

If it is successful, numbers will be increased to 200,000 over three years and over five years.

The population will then be built up to four million, spread over 40 hectares, restoring the self-sustaining oyster reefs that existed in the Firth, until they were fished out in the 1800s.

An Independent Research Advisory Panel (IRAP) of leading European Marine scientists has also been created. Led by Professor John Baxter the panel will have oversight of the DEEP project.

Dr Bill Sanderson, Associate Professor of Marine Biodiversity at Heriot-Watt, said: “This is the first time anyone has tried to recreate a natural European oyster habitat in a protected area. Working closely with Glenmorangie, we hope to create an outstanding environment for marine life in the Firth – and act as a driving force behind other oyster regeneration work across Europe.”

Oysters were once plentiful all along the coastline until many species were overfished to near extinction.

But Scotland's native oyster beds and other shellfish habitats are being revived and are at the highest levels in nearly 200 years.

Four years ago live oysters were discovered in the Firth of Forth, more than 50 years after they were declared extinct in the area.

At its peak, the Firth of Forth oyster fishery produced more than 30 million oysters a year and even Charles Darwin went out with the boats from Newhaven while studying in Edinburgh.

Over-harvesting caused the fishery to collapse by 1920, and surveys of the Firth of Forth in 1957 reported that oysters were biologically extinct.

Hamish Torrie, Glenmorangie’s CSR Director, said: ‘We are very excited to move DEEP to its next stage and have been hugely encouraged by the enthusiastic support that our meticulous, research-led approach has received from a wide range of Scottish Government agencies and native oyster growers – it is a truly collaborative effort.

"We are all very proud that in our 175th year the Distillery has such a pioneering environmental project right on its doorstep.’ Thomas Moradpour, President and CEO of The Glenmorangie Company, said: “DEEP is a vital part of our vision for a fully sustainable business.

"Supported by Moët Hennessy Louis Vuitton and our partners, we’ll do all we can to champion this innovative project, soon to be showcased at our Open Weekend at The Glenmorangie Distillery.’