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Love Oysters? Eating them helps the environment

Posted on: 17th December 2019

Love Oysters? Eating them helps the environment
If you love oysters we are lucky in Cornwall to have an abundance of choice for you! Cornwall is home to the worlds last remaining sail and oar powered, native oyster fishery and Truro river or Fal oysters are world renowed for their quality and sustainability and increasingly they are being appreciated this side of the channel despite many years of export to France.  Meet the oysterman Timmy Vinnicombe here.
We also have sucessful oyster farms in both the Helford River (native oyster) and the Camel Estuary (pacific oysters). Both produce high quality farmed and purified oysters for the local and international market.
The new kid on the block however also has a big potential...
In the last five years wild Pacific oysters (sometimes called 'rock oysters') have been rapidly taking over Cornwall's estuaries and bays.  The good news is they are exactly the same species as farmed oysters and they are delicious. 
Not only that, but by eating them you are helping us control this non-native species which is threatening our local marine wildlife. 
Pacific oysters were first introduced to Britain in 1926 and were brought into the UK to be farmed in the 1960's. At that time government scientists stated that this species would be ideal for aquaculture as, although they would grow well here, sea temperatures at that time were not high enough to allow the oysters themselves to reproduce. Since then we have witnessed the effects of climate change and in many parts of the UK including Cornwall wild populations of oysters have now become established. 
Unlike the native oyster (Ostrea edulis) which lives below low water, Pacifics tend to live on the shore and often attach to hard surfaces, rocky reefs, harbour walls, pontoons etc.  Each adult oyster can release up to 200 million tiny larvae each summer, which settle as spat and then rapidly grow. Eventually they are able to take hold on softer intertidal areas by growing on small stones and then attaching to each other. The oyster reefs created are razor sharp and they result in the loss of estuarine sand and mud flats, a very important and productive habitat that is vital as a feeding ground for wading birds and for important commercial fish stocks such as bass and bream.  
The scale of the invasion witnessed is incredible as has been documented by research by Cornwall Wildlife Trust, and Natural England.  Eventually as has already happened in other areas of Europe these oysters could spread to the subtidal where they are likely to out compete our native flat oysters.
Like all oysters, wild Pacific oysters have to be properly purified before they can be eaten, and they can only be harvested legally from designated shellfish waters. They tend to be larger and more irregular in shape than farmed oysters and they are full of meat. 
Cornwall Good Seafood Guide are actively promoting the use of feral pacific oysters, they are on our Recommended list, so why not give them a try?
Find out about our local oysters here:
Native oysters 
Pacific oysters 
Supporters of Cornwall Good Seafood Guide who sell oysters;
Rock Shellfish, Porthilly Farm, Rock - suppliers of farmed Pacific oysters from the Camel Estuary.
Wild Harbour Fish Company, Hayle - suppliers of depurated wild Pacific oysters from the Fal 
Wing of St Mawes- suppliers of Fal Oysters
Fal Oyster ltd supplier of Fal Oysters and wild Pacific oysters
Cornish Shellfish Company - suppliers of depurated wild Pacific oysters and Fal oysters 
Sailors Creek Shellfish company - suppliers of wild Fal oysters
Chef Guy Owen, with CGSG Matt Slater at the Fal Oyster Festival 2019 serving up fresh, wild Pacific oysters. Photo by Ellie Stones 

Cornwall Good Seafood Guide is underpinned by the Marine Conservation Society (MCS) Good Fish Guide. The first UK consumer guide to sustainable seafood. For more information visit

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