FOR thousands of years. native oysters thrived in the Dornoch Firth and, with little to disrupt their well-developed reef, they kept the calm waters crystal clear and played their part supporting other sea life.

But a 19th-century taste for their saline, silky flesh left them virtually extinct, with 13 million oysters distributed every year for more than a decade from Edinburgh harbours alone.

Now, an innovative project to restore long-lost oyster reefs back to the Firth has proved so successful it is being used as a blueprint for the restoration of oyster reefs across Europe. The example could see millions of native oysters return to European waters a century years after stocks were wiped out by overfishing.

Tomorrow (TUES), dozens of scientists, conservationists and oyster producers from across Europe will gather in Edinburgh at the second Native Oyster Restoration Alliance(NORA) to hear how various oyster restoration projects are now under way.

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Among the key projects it will examine is the Dornoch Environmental Enhancement Project (Deep), a joint initiative involving a team from Heriot-Watt University in Edinburgh, the Marine Conservation Society and distiller Glenmorangie, which has produced whisky in the area for 175 years.

The project saw divers place 300 laboratory cleaned oysters sourced from sustainable wild fisheries on the seabed in 2017. The oysters had been held behind a biosecurity firewall, and their shells scrubbed, sterilised and washed through using purified sea water before being selected.

Waste shell material was used last year to create the vital reef habitats required for the oysters to thrive and which had disintegrated after stocks were plundered for the nation’s dinner tables. A further 20,000 oysters were introduced to the site last year, with plans for 200,000 by 2021 and hopes they can help create a self-sustaining reef of four million oysters by 2025.

Once firmly established, the oyster population is expected to improve water quality, restore biodiversity and work hand in hand with Glenmorangie’s anaerobic digestion plant, helping to purify by-products created through the distillation process.

HeraldScotland:

The project, among the first of its kind in Europe, is now to be examined in detail with a view to including it in a blueprint for oyster reef restoration at sites in at least 15 European countries.

The plan could see native oysters thrive again in the waters around France, Germany, Sweden, Ireland, the Netherlands, Belgium, Italy and Croatia, as well as England and Wales.

Dr Bill Sanderson, Associate Professor of Marine Biodiversity at Heriot-Watt and Research Director at Deep, said: “We are developing a blueprint across European countries to establish what works and what doesn’t work. We have learned stuff along the way about how to restore reefs and there is bound to be more to learn.”

“There has been a groundswell of interest in restoring oyster reefs, and we are now establishing a baseline to work with. We tend to forget what natural systems looked like because we’ve not seen them ourselves.”

The Dornoch Firth is designated as an Area of Outstanding Natural Beauty, a Site of Special Scientific Interest, an internationally important Special Area of Conservation, and a Special Protection Area.

Glenmorangie’s anaerobic digestion plant, which opened in 2017, is designed to treat the distillery’s waste product and washing water, helping to reduce the chemical oxygen demand of the water released back into the Firth by 95 per cent. The established oyster reef is expected to take account of the other 5%.

The Dornoch oyster project is the forerunner among 17 reef restoration projects under way in Europe, many of which are said to have been inspired by the Scottish project’s success.

In some cases, oyster reefs are being developed with a view to supplying demand for fresh oysters from diners, raising the prospect of oysters returning to the dinner table as an everyday staple.

Oysters were once plentiful all along the coastline until many species were overfished to near extinction. At its height, hundreds of people were involved in fishing for oysters – the oyster bed in the Firth of Forth alone was 20 miles long by six miles wide, with harbours at Newhaven, Cockenzie and Port Seton hubs for oyster catches.

But stocks ran dry, and by the 1920s oysters – once enjoyed by people from all walks of life – were becoming a rarity. They were declared biologically extinct in the Firth of Forth in the late 1950s, while the few remaining stocks rose in price and became a food for the elite.

But Scotland’s native beds have been revived in recent years, with live oysters recently found in the Firth of Forth more than 50 years after they were declared extinct in the area.

Professor Henning von Nordheim, head of the marine conservation department in Germany’s Federal Conservation Agency BfN: “There is a real chance to restore large areas of our over-exploited marine ecosystems with native oysters, for the benefit of marine biodiversity and sea water purification all around Europe. We can learn a lot from each other at this g