Native oyster reefs once common say researchers

Stephane Pouvreau Two European flat oysters on a sandy seabed.Stephane Pouvreau
European flat oysters are now mainly found as scattered individuals say researchers

Researchers have discovered that reefs of native flat oysters once thrived along Europe's coastline.

A study by the University of Exeter and University of Edinburgh showed the reefs of European flat oysters were mostly destroyed more than 100 years ago by dredging and over-fishing.

In many places the Pacific oyster, also known as the rock oyster, has taken their place.

Researchers, who found evidence of former reefs from Norway to the Mediterranean, have called for more work to restore the flat oyster reefs.

Fishermen dredging for native oysters from a blue sailing boat on the River Fal.
Limited dredging for native oysters continues on the River Fal

Limited dredging of native oysters still exists on the River Fal in Cornwall, but according to the study, native flat oysters are now mostly found as scattered individuals.

Dr Ruth Thurstan, from the University of Exeter's team, based at Penryn in Cornwall, said native oyster reefs were an important habitat for other sealife and also filter water.

Restoration projects such as the Wild Oyster Project were under way across Europe which she said were "stepping stones to the return of these vital ecosystems on an international scale".

She said that few people in the UK would have have seen a native flat oyster.

"Oysters still exist in these waters but they’re scattered, and the reefs they built are gone," she said.

"We tend to think of our seafloor as a flat, muddy expanse, but in the past many locations were a three-dimensional landscape of complex living reefs – now completely lost from our collective memory."

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