Shellfish sector must increase mussel mass

A new study suggesting ways in which Scottish mussel growers can step up their production levels has been published today.

The study was commissioned by the Association of Scottish Shellfish Growers (ASSG) and Crown Estate Scotland in a bid to identify if collaborative investment, for example in vessels, harvesting equipment and infrastructure, might contribute to the growth of shellfish operations in Scotland.

Sorting mussels at the SSMG headquarters in Bellshill.

While Shetland’s mussel industry, which accounts for 74 per cent of Scottish mussel production, may be continuing to grow, farmers consulted as part of the study also suggested that the factors that have contributed to the growth of Shetland’s mussel sector – namely good growing conditions and supporting infrastructure plus council & community support – are absent or weaker in Scottish mainland sites.

The report, which was carried out by Poseidon Aquatic Resource Management Ltd, also notes that: “Many of the constraints identified point to the benefit of public-sector assistance in (a) providing the planning & exploratory groundwork to remove some of the regulatory and biological uncertainties of site development and (b) reducing capital costs/risk through financial instruments and facilitating more collaborative working.”

The report has received an enthusiastic response from stakeholders in the shellfish sector.

Crown Estate Scotland Aquaculture Operations manager, Alex Adrian, said: “The Shellfish Critical Mass Modelling study provides useful guidance for planners and other authorities on what might be needed to support the growth of shellfish farming in Scotland. It explores economic viability thresholds for the industry, and will be useful to prospective developers and existing businesses hoping to expand.

“A better understanding of economic drivers and challenges of a viable shellfish industry and how this translates into the nature of businesses and developments is vital if Scotland is to realise the undoubted potential of this sector.”

“A second element of the work,” he continued, “was to explore what measures may encourage growth of the sector, including how local communities might be involved so that they have a stake in developments and are involved in their delivery, such as through employment or service supply.”

A model for success

The study included the development of a financial model which indicates that only marginal gross earnings are achieved from mussel farms producing 150 tonnes or less, yet only 27.5% of Scottish mussel sites currently produce more than 200 tonnes.

The shellfish industry in Shetland accounts for 74 percent of Scotland's total mussel production volume.

The report states: “This might explain why mussel production on the Scottish mainland, which has stagnated at 1500-2500 tonnes per year for the last 15 years, may be a consequence of the sites not achieving the scale required to be viable stand-alone enterprises. Significant capital investment is needed to increase in scale, which can also be a barrier to growth.

“The growth of mussel production throughout Scotland will require increased scales of production. This can be achieved through the re-structuring of existing licenced sites (not necessarily increasing total licenced tonnage within a loch) to establish farm units that are viable.”

Spat collection conundrum

Interestingly the study suggested that, for larger scale operators at least, it makes more economic sense to buy in their entire stock of seed mussels rather than attempting to collect part of this share themselves.

“For small scale operations,” the report concludes, “spat collection is cheaper than buying in all the spat required. At larger scales this speculative approach is counter-productive. If spat settlement is not as expected, a top-up with bought-in wild spat is needed and the comparative benefit of spat collection is quickly lost.”

The report also suggests that the establishment of a commercial-scale spat hatchery could help to underpin the growth of the industry, although the authors admit that the economic and technical feasibility of such a hatchery was still unknown in Scotland, with Shetland’s pilot hatchery project still at too early a stage to fully assess.

Informed by the industry

Dr Nick Lake, CEO of the ASSG, was positive about the report, stating: “Our members offered first-hand production and business information to inform and provide detailed considerations as to how joint working could benefit both individual businesses and the wider community. The ASSG continues to promote the expansion of shellfish cultivation in Scotland as a highly sustainable and economically beneficial activity within some of the most remote Scottish locations.

“In order for the sector to continue to develop it is important that the wider business interests are recognised and planned for within the overall management framework for Scottish aquaculture. The ASSG looks forward to continued joint working with Crown Estate Scotland to ensure benefits are realised for both individuals and the wider Scottish economy.”