During the past two years that the SAGB Shellfish Promotion Project has been running, we have focussed on both the wild capture and aquaculture sectors. Innovation features highly in both areas and where we have seen great strides in sustainability and environmental responsibility. However, with pressures mounting on wild capture species and especially with mobile gear in the UK scallop fisheries, new avenues are being sought within aquaculture to establish consistent ways of producing quality, sustainable products that can supplement the wild landings. Oysters are obviously well-established in this regard, closely followed by mussels, but on the West Coast of Scotland, an ambitious and innovative practice is being carried out in the nutritionally rich and crystal clear waters of Loch Fyne.
New SAGB member, Jamie Macmillan, of Loch Fyne Langoustines, traditionally trawled for Nephrops norvegicus around the islands of the West and Hebridean coast and spotted an opportunity to take over an existing site in Loch Fyne at Tarbert, where pioneering work on farming Queen scallops (Aequipecten opercularis) had been carried out there on a small but viable and well-researched scale, taking two years to produce Queen scallops from first catching the seed or ‘spat’ to successfully harvesting the product grading and dispatching.
Recently, SAGB project consultant Mike Warner visited Jamie at Loch Fyne Sea Farms to see first hand, exactly how this remarkable bivalve could achieve much in terms of producing an ultra low-carbon alternative to the seasonal dredged and trawled queen scallop fisheries around the UK.
The farm itself, located to the North and South of Tarbert Harbour, to the uninitiated appears relatively insignificant in its physical impact on the Loch with the bulk of the farm’s infrastructure below the water with just the headline buoys and markers that delineate its boundaries. The two sites are geared accordingly to the capture of seed and then the growing on of the young stock which takes approximately two years. As we head out of Tarbert Harbour and pass the mackerel anglers on the pier, it’s only a relatively short steam to get to either of the farm’s two sites.
With the pressure on wild stocks coming into sharp focus and the perceived environmental impact of mobile gear, especially in traditionally fished areas such as the Isle of Man, the need for a sustainable solution could not have come at a better time and never more so in Western Scottish waters where a combination of MPA’s, gear limitation, NGO pressure and crew shortages has resulted in a potentially catastrophic depletion of the local fishing industry, and the accompanying knock-on socio economic effects. Could environmentally-responsible and sustainable aquaculture revitalise these ailing communities?
As we pull alongside the first headline buoy on the catching site, we’re in approximately 40 metres of water and not a dissimilar distance from the rocky shoreline of the Loch. The grapnel is thrown, the buoy hauled abroad and the revealed headline attached to the boat’s gunwale. The catching nets hanging off the headline (a bit like lengths of net curtain) are covered in a gritty slime where the spat fall from the spawning parent fish has attached itself. This seed will then grow on to the size of a fingernail before being detached and transferred to ‘Pearl’ nets for the next stage of their development.
Having inspected the seed catchers, we move to the Pearl nets on another part of the site. These pyramidal-shaped cages are suspended one above the other on a mainline, which again is attached to the headline. The juvenile scallops are transferred to them and then reside in there for approximately 8-9 months before they are again moved into the final stage; the ‘Lantern’ nets where they complete their growth for a further 18 months, before being harvested.
It’s obvious upon hauling the pearl nets, that not only the scallops thrive under these conditions and an entire juvenile ecosystem is emerging on the submarine infrastructure of the farm. Urchins, prawns, skeleton shrimps, juvenile brown crab, marine worms, seaweed and other molluscs are there in abundance on the nets. It’s obvious that the farm is also a host nursery area for so many other species and the fact that many filter feeders are involved, is a huge positive too for the water quality of the Loch.
We then steam the short distance to the final stage ropes, where the ‘Lantern’ nets are secured. As the scallops mature and put on weight they are continually graded on a monthly basis to ensure a correct stocking density, so optimum growth rates can be achieved. As the weight of the nets increase, more buoyage is added to compensate and to stop the gear descending to the sea bed thus putting it at risk of bottom dwelling predators such as starfish. After 2 – 2.5, years the queenies are then harvested. The process involves the craning of the long and by now, bulky, sea-squirt covered nets aboard the work boat, cleaning off the detritus first with a power washer. Once on the sorting table, the net is unlaced and its contents shaken out ready for cleaning and grading into commercial sizes, with any undersized fish (less than 40mm) being returned to the nets to grow on.
It’s a fascinating process and one that produces a wild protein product with zero artificial inputs and with a very low carbon footprint. The environment is not harmed in the process and in fact, more accurately, enhanced through the establishment of different species within and beyond the scope of the farm, attracting other commercial fish and shellfish species to what essentially develops into a protected area.
The proof of the pudding is of course, always in the eating and for any discerning seafood lover, there absolutely is no finer taste than a freshly shucked Scottish Queen scallop, eaten raw, only minutes out of the water. Saline yes but overwhelmingly sweet and to a seafood purist they are the ultimate hit. Less is more with these delicious creatures and with a ready and developing market in the UK as well as abroad, the sustainability of operations like this could go a long way to satisfying that demand, enhancing the environment and hopefully protecting the heritage of our often beleaguered coastal communities.
