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reLAKSation no 1139

Sustainable growth: Fish Farming Experts reports from AquaNor that when opening the Scottish Pavilion, the Scottish Rural Affairs Secretary, Mairi Gougeon said that ‘Everyone here recognises how hugely important aquaculture is to Scotland s economy and that is why the Scottish Government will continue to support the sustainable growth of this vital industry.’

In my opinion, if the Scottish Government really recognises the importance of salmon farming to Scotland and wants to support and encourage sustainable growth, then the Rural Affairs Secretary will reopen the discussion on the impacts of sea lice on wild fish rather than force the imposition on the salmon industry of a rather meaningless and pointless sea lice risk framework which will do absolutely nothing to safeguard stocks of wild salmon and sea trout.

I have said this time and time again that if the wild fish sector really wants to protect wild salmon, they would be willing to continue to discuss this matter. Instead, they prefer to avoid any debate on issues such as those I raise in this issue of reLAKSation.

Scotland risks weakening the salmon farming sector and at the same time having no wild salmon left in Scottish rivers. There is still a chance to have a strong viable salmon farming sector as well as preserving stocks of wild salmon, but time is fast running out.


Eyes wide shut: The Marine Directorate has just published a blog entitled ‘How Scotland’s wild Atlantic salmon are faring’ in which they look at ‘some of the ‘scientific’ data that underpins the management of this remarkable fish’. This blog has been prompted by the latest consultation gradings. I have discussed in previous reLAKSation’s how the Marine Directorate has compared disparately sized stocks and treated then as equal, when they are clearly not. This provides a misleading picture of what is happening to wild salmon.

The blog continues in an equally confusing vein. It says that the larger rivers, which contain most of Scotland’s wild salmon tend to be in good conservation with 80% of Scottish salmon estimated to come from these rivers. Yet, the blog also says that declines in the number of salmon from areas of good conservation highlight the need for action to safeguard this iconic species. The blog appears to suggest that the majority of salmon are in good conservation status but also that they are not. The graph showing the decline of the number of Grade one stocks from 61 to 34 from 2017, even if they are not comparable, should be doing a lot more than ringing a few alarm bells. Sadly, the Government’s implementation plan will do nothing to safeguard wild salmon. In my opinion, this is because the real damage was done a long time ago.

The blog suggests a few reasons why salmon are in decline, including salmon farming, the only one of the suggestions to have a link to more detailed information. So far, the blog has received three comments, all of which suggest more needs to be done to control salmon farming, as if this is the solution. They repeat the same old anti-salmon farming nonsense as promoted by the whole wild fish sector. I was recently made aware of one critic on Twitter who continually criticises the salmon farming industry but posted the following photo. Why are so anglers happy to ignore the basic rules of conservation regarding salmon angling, but still blame everyone else when there are no fish left.

I am also reminded of one very vocal salmon farming critic who regularly makes a point of highlighting the river Strontian as an example of the damage salmon farming causes to a wild salmon river. The Strontian is a small spate river that empties into Loch Sunart. I have been recently looking again at Sunart in more detail because it is one of the eight proposed Wild Salmon Protection Zones that is of extra concern.

There is very little written about wild salmon and sea trout around Loch Sunart. The only river to receive Marine Directorate attention is the river Carnoch near the head of the loch. The Conservation gradings show that the recent catches amounted to just a handful of fish. There does not appear to be any record of catches from the nearby river Strontian, however Fish Lochaber says that although numbers have declined over recent decades, improving marine conditions and a restoration programme means that fish are returning to the river.

Over the last seventy years, the average annual catch of salmon from the whole of the Loch Sunart Fishery District amounts to about 23 fish a year. Interestingly, catches jumped to around eighty fish in the early 1970’s and again in the late 1980’s. These catches are well above average but following the second peak, catches have declined, in line with much of the west coast, but as this decline coincided with the arrival of salmon farming, then critics have argued that salmon farming is the cause of all the problems of salmon and sea trout on Scotland’s west coast. In his book Rivers and Lochs of Scotland – An Angler’s Complete Guide, the late Bruce Sandison, who was an ardent critic of salmon farming, wrote about the Carnoch river “greatly reduced numbers of salmon and sea trout compared to days past caused by sea lice infestation from the plethora of factory salmon farms which now litter Loch Sunart.”. Regarding sea trout he cross references entries for Loch Shiel and Loch Eilt.

About these lochs he writes that “This once famous sea trout fishery has been ruined in recent years because of fish farm sea lice attack on wild salmonids. In the more recent past upwards of 1000 sea trout were taken each season but because of the collapse of West Highland Sea trout stocks caused by sea lice infestation from factory salmon farms, this system now struggles to produce 7 fish per season.”

In 1987, a paper given at a symposium held at the Scottish Marine Biological Association included the following graph of sea trout catches from these fisheries for the time prior to the arrival of salmon farming:

A more recent guide to the catches from the local fishery district shows the decline continues in line with declines on the west coast and elsewhere, these lochs, although nearby, are not connected to Loch Sunart. There was one small farm nearby, which like in Loch Ewe is blamed for wiping out a whole sea trout fishery, even though the collapse occurred before the farm was even established.

Unfortunately, most of most vocal critics have little qualification to make any judgement on the causes of wild salmon declines other than the fact that they can put two and two together and make five. To them, and to many of the wild fish sector, the presence of salmon farming is so blindingly obvious as the cause of the declines that there is no need to look for any other possible reasons. Yet since the arrival of salmon farming to Loch Sunart in 1985, 604 salmon have been caught and killed by netting, with 101 killed as late as 2014, 29 years after the arrival of salmon farming. (For comparison, anglers have killed 517 fish over the same time period).  More significantly, in the period 1972 to 1982, a total of 5,657 salmon were caught and killed by the nets and this is from a loch system with an average rod catch of just 23 fish. This is a huge loss from the breeding population and it’s no wonder that the stock has collapsed. It is also worth noting that whilst 5,657 salmon are reported as having been killed, the record is full of massive gaps when either fishing never took place, or the fish catch was never reported. It is unclear which it is.

The same pattern has been repeated in other west coast sea lochs and whilst the angling sector campaigned long and hard for the closure of nets because netting was catching and killing the fish anglers wanted to catch and kill, there has never been a real analysis of the impacts of netting on the most fragile of Scottish salmon stocks.

The latest analysis of conservation grades already sends out a clear message that the killing of any wild salmon should be made illegal, but the angling lobby has always seen the protection of the fisheries as being more important than the fish so 2024 will not be the year that salmon conservation takes precedence.


Interpretation: This year the Marine Directorate published a summary document of salmon and sea trout catches. This followed on from a similar document the year previously. However, in 2020, salmon and sea trout statistics were published as two separate documents rather than just the one. These documents have evolved over the years but one of the biggest changes occurred in 2013 when the documents were significantly edited. In 2012, the statistics document included a section titled ‘Interpretation’. In 2013 this section was missing.

Given that the Marine Directorate has just published its blog on how wild salmon are faring, historic interpretation of the state of the salmon now makes interesting reading. I have copies of the 2011 and 2012 documents, and both provide almost an identical interpretation with one exception. This is in reference to net catches which in 2011 were said to be less than 10% of those taken in the past and have remained at this level for the last decade whilst rod catches have continued to increase (although they had peaked the year before). A year later, the document stated that net catches are now around 5% or less of those taken in the past and have remained at this level for the past decade, whilst annual rod catches have continued to increase.

This is puzzling, how can net catches remained at 10% for the last decade in one document whereas the other one says they have remained at 5% for the same last decade?

However, the biggest puzzle is that both documents state that ‘Observations of salmon numbers at Marine Scotland monitoring sites suggest that overall marine survival of Scottish salmon has now stabilised or is increasing’.

The graph of salmon numbers returning to Scottish coasts as well as the graph of catch data would suggest that the interpretation of the state of salmon in 2011/12 was completely misplaced. Even at that time, it was apparent that all the measures of salmon abundance were headed in just one direction. It is therefore not surprising that interpretation of the data was dropped from these documents.


Sea Trout: the comparable sea trout documents also include an interpretation which was also removed in subsequent years. The sea trout statistics at that time included an assessment of regional catches which also makes interesting reading. The document states that

“Analysing the catch data at finer geographical scales reveals differences among regions in the relative strength of 2012 catches compared to available historical data. Annual reported rod catch (retained and released) for each region was ranked over the time series from 1952 to the present (1=lowest, 61=highest). Thus, a rank value of 1 would indicate that the catch for that year was the lowest recorded in the time series for that region, while a value of 61 would indicate a region’s highest recorded catch.”

The two images are for 2011 and 2012. The 2011 image shows that catches of sea trout are poor all along the west coast, not just in the salmon farming areas. Catches are also very low in the northeast and the east, where there are no salmon farms. Catches of sea trout fell in parts of the west in 2012 but increased in others. What is clear is that declines in sea trout catches in the salmon farming areas are not unique and that similar declines have occurred in parts of Scotland where salmon farming is not present. Unfortunately, the interpretation provided does not include any explanation for the differences. The only reason given is that fish may not be reproducing as much as they used to.

However, if one listens to the angling sector, salmon farming is the main problem for Scottish sea trout. Clearly, it is not.


More sea trout: Although Sea trout are not the main feature of the SEPA risk assessed framework consultation, they repeatedly appear in my research for the response to the second part of the consultation. Much of the earlier work on sentinel cages took place at the Shieldaig Field Station located on Scotland’s west coast.

According to the Scottish Government website, the Shieldaig Field Station was established because:

“Concerns regarding declining sea trout populations on the West Coast of Scotland in the late 1980s and early 1990s led Scottish Government to set up a long-term monitoring programme on the River Shieldaig in Wester Ross during the mid-1990s.”

The following graph shows the decline of sea trout numbers caught by all methods from 1952 onwards. The data is from the Scottish Government database.

I would ask what changes in west coast sea trout catches during the 1980s and 1990s prompted the need to establish a Field Station because the graph shows a consistent decline in catches since 1952, thirty years before salmon farming became firmly established on the west coast.

I would suggest that the motivation for the Shieldaig Field Station came not from any solid data but simply because anglers had been complaining about salmon farming ever since its inception. The Scottish Government websites states

“The role of salmon farms, and in particular sea lice, on the observed declines of sea trout has been the subject of considerable controversy.” Of course, there was considerable controversy just because neither the Scottish Government nor the angling sector could provide any firm evidence to support their claims against salmon farming.

The website continues that “The work programme at the Shieldaig site was therefore designed to provide data to investigate potential links between lice, farms and sea trout.” The aim was to provide the evidence to support the angler’s claims. The reality is that up to present, they have failed to do so.

I would argue that this is why there is so much reluctance to talk to people like me because there is no evidence to support the claims.

Interestingly, I recently acquired a copy of a paper from the early days of sea lice research, the abstract of which states: “Mortality of heavily infested fish was directly observed”. This is an interesting aspect of sea lice infestation because the general view is that fish that have died of sea lice infestation are rarely seen or reported. I am still in pursuit of clarification so will not identify the paper just now, but I have been in touch with two of the three authors and asked if these mortalities were a one off, whether they occurred in more than one river system and for more than one year. I have also asked if photographs were taken of the dead fish in situ. Both responses to date say that they don’t have that data or photographs but that someone else might,

Given the importance of such data, it does seem odd that information, whether written or photographic, appears to be elusive. This is the problem with sea lice research. A lot of claims are made, but very little real supporting evidence is ever provided.