Shellfish Conference
Mussel man of Devon
John Holmyard, managing director of Offshore Shellfish, is setting up the UK’s first large-scale offshore mussel farm, between three and six miles off the coast of south Devon.
The project is a realisation of his long-held ambition to scale up production of rope grown mussels to between 5,000-10,000 tonnes per year, in order to access volume markets. This had been impossible in a Scottish loch, where he successfully farmed for 20 years.
The first trial crop of mussels is now ready for harvest, but the process involved in reaching this milestone has been arduous.
For a start, there were so many questions to answer. Would there be a spatfall in the chosen location? Would the equipment weather storms? Would the mussels stay on the ropes in such a dynamic environment? Would there be enough working days at sea to make the project viable?
Undaunted, John started the process of seeking sites nine years ago, and received the final piece of paper that allows him to sell mussels at the end of October this year.
‘The initial challenge was getting a Crown Estate lease and a marine licence for our three sites,’ he said.
‘This was a lengthy process that stumbled along and involved us jumping through a lot of hoops. Because no one has undertaken anything on this scale before, there was no precedent for offshore licences, and every interested party was allowed to offer an opinion on our proposals. Which they did!’
Before beginning any development, John commissioned a detailed baseline survey, which no other shellfish farm has ever done, and followed this up with an extensive and ongoing monitoring programme, which will show what changes may be brought about by such a large scale development.
‘With permission in place, we then needed to get our waters classified as a shellfish harvesting area, but again there was no precedent for doing it six miles offshore.
‘It took a lot of negotiating to put a procedure in place, and in the meantime, we couldn’t even give mussels away.
‘However, following a rigorous testing process, the water was found to be Class A, making it the only mussel farm in England with such a classification.
‘Clean water is one of the bonuses of farming offshore, and it means we can sell straight off the harvesting boat, which is also our registered despatch centre,’ he said.
“Every interested party was allowed to o er an opinion on our proposals. Which they did!”
A further challenge was deciding what type of e uipment to use, and John travelled extensively, looking at systems in use around the world.
He was looking for something that was simple, robust, repairable and mechanised, and eventually turned to New ealand companies Fielder Marine for seabed-screw anchors, and Yuality E uipment for specialist mussel rope.
hnable to find the flotation necessary for the location, he designed it himself, and worked with Fusion Marine to turn it into reality.
The anchors are six metres long, and re uire a specialist drill to install them, but they are highly secure and have been proved through several severe storms.
We determined which type of rope suits our conditions best, and the floats do exactly what they were designed to do, which is to dampen the effects of large waves,’ he said.
With the trial e uipment in place and fingers crossed for a spatfall, John was delighted to find firstly that it settled in abundance, and secondly that it grew unexpectedly fast, with some reaching harvestable size within six months of settlement. This means that he can achieve a full cycle within a year.
Now he knows that the system works, John is busy building out the farm, which has permission for 790 headlines.
To do this, he needed a purpose built boat that would cope with the drilling operation and also act as the first harvesting vessel.
The new boat, built by Alnmaritec, was launched in May and named after John’s first granddaughter Alysée.
With the first year under his belt, John is confident that the new operation is headed in the right direction, but says there is still a long way to go.
For instance, the risks we face are the same as any other mussel farm it’s just that they are more acute when you are offshore,’ he said.
Paradoxically, one of the biggest challenges he faces is also the new farm’s biggest strength, and that is the impressive growth rate which compresses all the farm’s activities into very short time frames, and causes logistical challenges.
John is determined to make full use of the uni ue opportunity that has been created by the farm and to look at the wider possibilities beyond growing mussels. To this end, the company has just committed to supporting a PhD student at Plymouth hniversity, who will look at its wider socio-economic benefits..