• Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust
  • Community of Arran Seabed Trust

The monk and the fish farm. John Campbell

John Campbell offers this considered review of monitoring data contained in a recent Freedom of Information disclosure. The Monk and the Fish makes sense of two years of correspondence and reporting related to the operation of The Scottish Salmon Company's fish farm in Lamlash Bay.


I wonder what Saint Molaise or Molios in today’s parlance, who is reputed to have once lived as a hermit on the Holy island in Lamlash Bay, would have thought about a salmon fish farm named after him and located in the bay. Maybe he would have praised its aims to feed the masses or maybe he would have questioned its need knowing that on his doorstep fish would have been plentiful in the surrounding coastal waters at the time.




Today of course we have the fish farm and little or no fish in the surrounding seas, which doesn’t make sense in terms of ecological diversity. The NTZ in Lamlash Bay is a start to address this imbalance and it is important to grasp this opportunity for the bay to provide a focus for recovery of the marine environment.




Outdated philosophy

COAST keeps an eye on the fish farm to ensure that those responsible for its operation keep its possible impact on the waters of the bay within its existing licence parameters for the foreseeable future. SEPA has already turned down an application to expand the site beyond its present licence requirements because the site appears to be operating very close to or perhaps even exceeding the assimilation capacity. The dilute and disperse approach adopted here for disposing of environmentally significant contaminants is incidentally a pollution disposal philosophy commonly practiced in the 1970’s and earlier which has largely been rejected today as an acceptable means of contaminant disposal on land.

So what is happening at The Scottish Salmon Company’s (TSSC) operation at St Molios and how do we know?  At least it is not truckloads of dead fish that has been the case in the past!  The answer is that SEPA has provided COAST with information in response to a ‘freedom of information’ request and the collection does provide a very interesting window on what is going on.

Summarising the means by which marine fish farms are regulated in Scotland, each farm project is subject to a renewable CAR licence, Water Environment (Controlled Activities)(Scotland) Regulations 2011, which is granted by SEPA on the basis that the sponsor can demonstrate that under certain constraining conditions such as scale of operation the site will provide the necessary assimilation capacity. This is measured by applying a standard mathematical model of dispersion and deposition of waste sediment called AutoDEPOMOD and drawing a conceptual curtain in the waters surrounding the site beyond which certain limits of contamination must not be exceeded.


Important to consider 'site specifics'

No one site is the same with differences in tidal flow, sea bed topography etc all of which provides the basis for the modelling exercise so it is not surprising that each site has its own dispersion characteristics and therefore its own restrictions in scale in order that it can achieve the desired limits. SEPA’s regulatory involvement extends to limits to quantities of fish stocked (biomass) and hence quantities of food to be used and also to limits to amounts of medicines and other chemicals applied.  SEPA also specifies the way regulated parameters are monitored and results reported.

The Scottish Pollutant Release Inventory (SPRI) are available for reference by any interested party.


The reported results for St Molios reproduced here by permission of SEPA provide an impression of the scale of quantities used which would not be dissimilar from any other moderately sized operation.  All quantities are reported in kilograms.




















Emamectin B






Organic carbon






Nitrogen content






Phosphorus  cont.
























*<rt refers to results that are below the reporting threshold established by the regulator as part of the site licence.


These reported data do not tell us much in themselves unless compared and contrasted with figures from similar operations elsewhere. Data are available for other TSSC sites and relevant comparative information is available for a number of operations in nearby Loch Fyne. Converted to tonnage quantities by dividing by 1000 shows that up to 200 tonnes food and faeces are discharged to the bay each year as well as an astonishing 2 tonnes or more of copper.  Copper is added to keep the cage structures clean in the same way that antifouling compounds are deployed to keep ships hulls clean with in some cases well known catastrophic impact.  We will have to wait until August to see the 2010 figures.


A revealing "data diary"

We have been provided as requested with something akin to a diary in terms of correspondence exchanged between the company and SEPA spanning a period over the last two years. In essence there are three strands of information. The first is all about the monitoring protocol, which was last formalised in 2009 along with the licence but which was revised in response to a TSSC request in terms of both the benthic survey approach and reporting of in-feed treatment residues.  Sampling transects along the line of tidal direction are confirmed and grid references for sampling locations are specified.

The second strand is an exchange of views between TSSC’s predecessor Lighthouse Caledonia, its regional operations staff, and SEPA concerning the overall performance of St Molios. SEPA acting on its own seabed condition report classified the results under their performance assessment scheme as a significant breach and rated its performance as ‘poor’. A management plan was called for along with a warning of the possibility of tightening biomass and stocking density limits to tackle the problem of accumulations of organic matter in sediments and resultant impact on invertebrate fauna.  In the event by July 2010 SEPA’s position was that changes in cage design and reduction in biomass stock were proportionate and licence changes were deferred. The site had been approved before the introduction of dispersion modelling as the basis for site specific regulation and this omission needed now to be corrected.  After a considerable fallow period at the site over this last winter it is apparent from observation that the site resumed production in March.

The third strand consists of a rather esoteric exchange of views between the present owner and SEPA over who was responsible and when for exceeding environmental quality standard (EQS) for emamectin in sediments following its use in in-feed dosing to address actual (or anticipated) sea lice infestation. The company’s environmental manager is clear that it is TSSC and Lighthouse Caledonia’s predecessor company, Marine Harvest, which is likely to be the offender. Records are said to be opaque or deficient but breaches are believed to have occurred in amounts and frequencies of use exceeding agreed maximum treatment quantity (MTQ).  The corporate memory here seems surprisingly deficient !  However it is claimed that levels are on the way down to more acceptable levels. SEPA weighs in at this stage to report that on the contrary their own independent survey work on site indicated low levels back in August of 2009 well within the EQS but that by the following year limits were being exceeded.

The fact is that TSSC has had no option but to address concerns raised by the regulator about assimilation capacity at this site and to offer a reduction in proposed stocking levels for the next cycle of production reducing output by 10%. The company has also replaced square cages by circular cages, adopted a larger footprint within the licensed operational area and is said to have installed underwater cameras to improve feed management.  COAST will continue to monitor performance now that there is much more information that can be made available which has relevance to the environmental condition of the bay as a whole.

John M Campbell
26 April 2011

COAST Vacancy

Director – Operations and Development
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