Native Oyster Restoration

Tuesday 19th July 2016

Major milestone in ENORI project - More than 25,000 mature native oysters have been reintroduced to an Essex estuary by the Essex Native Oyster Restoration Initiative (ENORI) - in an attempt to restore a nationally important breeding population that once supported hundreds of fishermen.

ENORI is a joint venture between Essex Wildlife Trust, Blackwater Oysterman’s Association, Zoological Society of London (ZSL), Blue Marine Foundation, Cambridge University, The Nature Conservancy, River Roach Oyster Company, Colchester Oyster Fishery, CEFAS, Natural England, the Environment Agency, and the Kent and Essex Inshore Fisheries Authority (KEIFCA).

The event is a milestone for ENORI and a significant step towards the restoration of Britain’s native oyster beds. Populations of the European Native, or Colchester Oyster (Ostrea edulis) are estimated to have been reduced by more than 95 per cent due to historic over-harvesting, disease, competition from invasive species and predators.

Oyster beds used to be an important structural and ecological component of Britain’s bays and estuaries, fuelling waterside economies for centuries and forming a ubiquitous part of our coastal culture. The popular shellfish are known as ‘ecosystem engineers’ because they facilitate the wider conditions for nature to thrive – stabilising shorelines, filtering water and providing vital food and habitat for coastal wildlife.

Essex Wildlife Trust staff, with the support of 30 volunteers, individually marked 2,500 of the oysters so they can track their progress, before they were relaid in the Blackwater, Crouch, Roach and Colne Marine Conservation Zone (MCZ). The MCZ was designated by the government three years ago, following survey work by Essex Wildlife Trust, the Blackwater Oysterman’s Association and University of Essex, with the conservation objective to recover the native oyster and native oyster beds.

Essex Wildlife Trust’s Living Seas Co-ordinator, Sarah Allison, said: “The Native Oyster is one of the UK’s rarest and most precious marine animals. Intrinsically linked to Essex, any loss of this iconic species would be felt far and wide, so it is great to be working on this ground-breaking project, which will hopefully begin the reversal of the oyster’s decline, with so many different partners.”

Mersea oysterman Allan Bird said: “The oyster industry in West Mersea, which is the home of the native oyster in the UK, is pleased to work with Essex Wildlife Trust, Natural England, ZSL and KEIFCA and wish to thank everybody involved in the project. Our long history of oyster culture stands a good chance of being rejuvenated through this exciting venture.”

ZSL Conservation Programme Manager Alison Debney said: “Starting this brood stock of native oysters marks real progress in the recovery of one of Britain’s most valued and historically important marine species. Oyster beds have suffered from poor breeding success over the past few years, with this enhancement we are hoping to kick start the population again and pave the way for future restoration efforts and investment.

“Dredging is prohibited in the area for the next few years and will hopefully continue to be until oyster stocks are sufficiently recovered to begin sustainable harvesting.”

The ENORI project has been supported by Selfridges through its Project Ocean campaign, while the long term monitoring of the oysters will be supported by volunteer dive network Seasearch.