History of Loch Ryan. Location of the beds

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1 History of Loch Ryan The Loch Ryan Oyster Bed dates back to 1701, when King William III, granted a Royal Charter of the oyster bed to the Wallace family. The family live on the shores of the Loch, and the rights to the oysters bed have been in their family ever since. Tristan and David Hugh-Jones were asked by Ben and Malcolm Wallace in 1996, to come and help run the oyster bed, as they have experience of breeding and managing an oyster bed. Tristan and David have been growing oysters in Cork, Ireland since 1969, which is probably the only place in Europe that has successfully bred the Native Oyster. Location of the beds Loch Ryan is situated in South West Scotland, and the Loch itself is about 12Km long and 4Km wide. It is certainly one of Scotland s largest oyster beds. We fish the oysters from the sea bed, by dredging them, using our boats the Vital Spark and the Haematopus. The Vital Spark is fishing most days the weather allows, and she has a skipper, Rob and one crew, John. A typical day would be to leave Stranraer harbour, at the south of the loch where the boat is moored, and steam up to the main oyster area on the east side of the Loch, near to Lefnoll Point, circled in red. Here the bottom is harder, and the shells sit well on the seabed, and they can be harvested quite well.

2 The water movement on the east side of the Loch is much greater, and with this movement comes more food to help the oysters grow. We fish up everything on the bottom, and sift through the catch on the stern of the boat. (see photo below) We hand grade all the oysters on the boat into three grades depending on their weight. We are generally harvesting oysters between about 75g (No.4) and 150g (No.1) in size. Most days we are able to catch about 2,000 oysters, of these marketable oysters, but to find them we have to sift through 40,000 smaller ones that are too small. These oysters are the future of the bed, and they are densely re-laid into well marked beds. The benefit of relaying the oysters close together is that they are near to each other, so that in the summer months when they breed, there is much more chance that the male will be able to fertilise the female oysters eggs. Stock When we took over the running of the bed in 1996, a survey showed that the total population of oysters in the Loch was thought to be around 1 million oysters. Through some careful management, and harvesting only the very largest for the market, we have been able to relay plenty of oysters for future years. These oysters will grow, and also be brood stock for about another 5 years or so, until they are harvested. The oysters grow at a rate of about 11g per year, so the by the time you serve an oyster, it is about 8 years old, much slower growing than the Rock Oyster. Summer breeding programme We generally stop harvesting at the end of April or May, and allow the oysters to breed. As the water becomes warmer, the oysters put their energy into the production of eggs or sperm. This takes quite a few weeks until the gonad is fully developed, and when the water temperature is up to 18 degrees or so, the males spawn, releasing their sperm into the water. These then are filtered by the females, and are captured in the gills of the oyster, where the sperm fertilise the eggs. Each

3 oyster produces about a million larvae, and these are free swimming in the water, where they grow from about 1/4mm to 1/3mm in size, over a period of about 10 days. Naturally, during these days, the tide washes the larvae in and out, on every tide, but amazingly in Loch Ryan, some of the water is retained, and some larvae do survive and are able to settle on some shell on the sea bed. We have had successful breeding most years, but some years, especially the hotter ones, we do manage to get a very good crop. This is the only oyster bed in Scotland that is self-sufficient, and by harvesting the oysters slowly, and replacing the small oysters into beds, we hope to build a larger population, which will then breed more, producing more to sell. The Oysters The oysters have a thick shell, probably due to their slow growth, with a plump, almost crisp bite to them. They are salty, and have a nutty, real taste of the sea. Quality Awards Our efforts have been recognised by the Crown Estate, and in June 2013, we were Winners at the Scottish Marine Aquaculture Awards. In 2013, we were winners of Scotland s Best Native Oyster run by the Association of Scottish Shellfish Growers, and this year we have been shortlisted for the RSPB Nature of Scotland Marine Award. Tristan Hugh-Jones sits on the management committee of the Association of Scottish Shellfish Growers, and is the chairman of the mollusc committee of the Shellfish Association of Great Britain.

4 Distribution of our oysters We fish the oysters every day, and at the end of the day, the oysters are bagged up into mesh bags and stored on the foreshore. The oysters then harden off on the shore, and get used to being out of the water, on every tide, twice a day. This sort of teaches the oysters to be able to survive out of water better, which improves their shelf-life. Every week the oysters are packed into 25kg sacks and delivered overnight to our depot in West Sussex. Purification and Packing The oysters are unpacked and placed into our depuration tanks, for a minimum of 42 hours. We have built 8 state of the art, fully approved, depuration tanks, each of which can hold up to 6000 oysters. The seawater in the tanks is circulated under UV light every 15 minutes to sterilise the water. This is a very important part of the process, as it is at this stage that the oysters clean themselves by filtering the water, so purging their gut to

5 get rid of any unwanted bacteria. We often extend this time, to offer the oysters more chance to cleanse themselves. When all the tanks are running, we are pumping 100 tonnes of water through the tanks / hour. We test the oysters on a monthly basis and every test we have had since we started purifying oysters has been acceptable. Loch Ryan Water Quality The water in Loch Ryan is of a very good quality. We are monitored on a monthly basis by the Food Standards Agency, and the results are used to classify the water. We have Grade B waters from September to December and Grade A from January and April. All out test results for 2014 have been of a Grade A standard. We are audited by the SALSA scheme on a yearly basis, and passed our re-inspection in May 2014.

6 Ordering Oysters We are able to deliver oysters Monday Friday, and the order needs to be placed the day before. It is best to phone, but we also can take orders: Office and orders telephone: Office and orders Tristan s mobile: Tristan s tristan@oysters.co.uk Wigton Free Press, January 2012