A life in oysters
The path to achieving of the biggest native oyster restoration projects has not been easy, as Nicki Holmyard reports.
David Hugh-Jones, of Rossmore Oysters, gave a fascinating talk at the Shellfish Association of Great Britain (SAGB) annual conference this year, in the members’ slot. He truly is a survivor of the oyster industry and gave me permission to use his story.
David’s interest in native oysters (Ostrea edulis) started in the mid-1960s, when he worked for the agricultural side of Shell. Excited by the potential of growing this species, he started his research and was pointed towards the MAFF (Ministry of Agriculture, Fisheries and Food, as it then was) shellfish laboratory in Burnham-on-Crouch, Essex.
There, he learned that most of the native oysters in England’s east coast rivers had died in the big freeze of 1963. He was also disconcerted to hear that severe winters had occurred on average, every 14 years before then.
David and Tristan, Rossmore Oysters
“I thought that was about the time needed for such a very slow-growing crop to just about break-even!” he says.
Seeking warmer waters, David headed west to Cornwall, where his plans stalled when he discovered that the Fal Estuary was a public fishery, and the Helford River was owned by the Duchy of Cornwall.
The was a solution, however, as David explains: “Then the penny dropped, there was still Ireland – a lot further west.
“I gave notice to Shell, learnt to dive, bought the gear, made myself a wetsuit, and left for Ireland in a van I could put a mattress in, which had I bought for 12 pounds 10 shillings!”
David received welcome advice from the Department of Fisheries and the Irish Sea Fisheries Board (BIM) and set off around the coast to find a suitable place to farm, donning snorkelling gear to investigate the seabed.
Ponds at Rossmore
“When I swam in the North Channel in Cork, which was about one metre deep at low water, the bottom was thick with old oyster shell, and there were three oyster middens dating back thousands of years on the shore. This had to be the site,” he says.
David struck lucky when he met Eric Edwards, BIM Fisheries Development Officer, on secondment from MAFF in Burnham. Eric was later to become Chief Executive of the Shellfish Association of Great Britain (SAGB).
“He gave me a job for the summer on the Galway oyster bed and a very welcome salary of £5 a week. I learnt a lot there!” David says.
But how to restore his own oyster bed? It wasn’t possible to find enough mature oysters to seed it, and unlawful to remove small oysters from any public fishery in England, Scotland or Ireland.
Spawning tanks had to be the answer
David had come across the pre-war work of Dr HA Cole on using the mussel-cleansing tanks, at the Fisheries Experiment Station Conway, as spatting tanks for native oysters. He also read up on the post-war work of Peter Walne, which paved the way for commercial oyster hatcheries, such as John Bayes’ pioneering Seasalter Hatchery at Whitstable.
He says: “My gut feeling was that hatcheries were not the answer for our native oyster, but I went to see both scientists. Peter Walne thought I would be taking a retrograde step by using spatting tanks, but Dr Cole, by then the Chief Fisheries Scientist for MAFF in Whitehall, told me he didn’t see why ponds shouldn’t work on a commercial scale and suggested making use of butyl rubber liners, as concrete would be expensive.
David and Bridget Hugh-Jones
“A few years later, I was pleased to take him a basket of pond-produced oysters, and he took me out to supper to celebrate!”
David also visited Yerseke, the centre of oyster-production in the Oosterschelde in the Netherlands. He met Professor Korringa, whose 1941 250-page publication was the acknowledged bible on the biology and farming of the flat oyster.
“He had records from 1870 to 1946 of sales, broodstock numbers left on the beds, water temperatures in July above the critical 19°C and, of most significance, the resulting spatfall on tiles and mussel shell. This was the blueprint I needed to develop a natural fishery and comparing the volume of the Oosterschelde to the North Channel, I reckoned I was going to need six million broodstock to get the old bed reproducing successfully again!” David says.
By early 1970, he had acquired an Oyster Fishery Order in the North Channel, which gave him oyster-farming rights for no rent and in perpetuity. He built a pond to breed oysters in and persuaded Paddy O’Keeffe, Editor of the Irish Farmers Journal, to back him with Irish farmers’ money and to become Chairman of the company.
“Paddy was a great support, and if ever I had to ask him if he knew anyone in a particular ministry, he would invariably ask: “Would the minister do?”
Wife Bridget came on the scene in 1970, and David had to persuade her that oysters came first. Any thoughts of luxury living were out!
“I spent six years examining water from the pond with a microscope, before we were able to develop 21 more ponds to undertake proper experiments, which involved buying a small island and shifting 100,000 tonnes of earth,” he says.
Spat after four months in the sea
Ten years later, a diving survey of the beds by Cork University found 13 million oysters aged one year and older, which was more than twice the number David thought might be needed to get natural recruitment in his channel.
However, despite the oysters growing well, there was no sign of them spawning. The reason turned out to be persistent high levels of TBT (tributyltin) from anti-fouling paint in the sediments of Cork Harbour.
The next catastrophe came in the form of a deadly infection caused by the protozoan parasite Bonamia ostreae. David had inadvertently introduced this by buying oysters from the north-west of Ireland to boost sales and relaying any left unsold.
“Unknown to me, they contained oysters illegally imported from France, where Bonamia was rife, but the result was that we lost 98% of all the oysters on our densely stocked beds,” he said.
David with oyster shells
“We hired another boat and were landing 400 baskets a day to rescue just eight baskets of live oysters to sell. We were devastated but couldn’t just give up!”
David knew that his company was the only one in Europe able to breed native oysters in any quantity, and specifically, from oysters where both parents had survived past their third-year spawning, which is when Bonamia kills them.
“If there was any chance that resistance to this infection could be bred into them, we had to go for it,” he said.
David had just enough broodstock for four ponds for the first two years but was back to the full 21 ponds for the second generation. After two generations, he had more oysters to sell than ever before. There were still losses, but the oysters were lasting longer, and he was soon able to breed from five-year-olds.
Rupert and Tristan, Rossmore Oysters
“What remarkable resilience our native oyster has, given a bit of help! We are now on to our ninth generation and fingers crossed, I think we dare to say that Bonamia is no longer a problem for us,” he said.
TBT levels in the local sediments have now sunk to a low-enough level to enable O. edulis oyster larvae to survive in the North Channel again, and David hopes that in a few more years, sons Tristan and Rupert may be able to claim the restoration of a native oyster bed in Europe.
The family have also looked after the native oyster fishery in Loch Ryan, Scotland, for the past 28 years, in partnership with the Wallace family, which was granted rights to the fishery in 1701.
David says the outlook is good: “A survey last year estimated a healthy stock of 23 million oysters in the loch, which is great news for the future of this fishery.”
