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LOCH EISHORT HABITATS

This page has to be verbose (4 pp. A4) if I’m to describe and discuss properly the habitats in and around Loch Eishort and their circumstances as industrial development looms. Some habitats are widespread and found in many places, yet should never be considered so trivial as not to matter when damage or destruction threaten. Others are uncommon or rare and must be protected with all the vigour we can muster.

What is most noticeable about the south Skye lochs situation is that, when we began considering environmental vulnerability here, only a few fragments of biological information existed. It was then that we started to discover and realise just how special the place is, a biological treasure house set in the most magnificent of landscapes.

Who was supposed to find out, though? We soon discovered that SNH had begun a seabed survey of some sort, back in 2007 I think, but the weather deteriorated as they headed south along the Skye coast and the expedition was abandoned just as the research vessel approached Loch Scavaig from the west. The weather has been suitable so often since then, but the survey was never completed and knowledge about the south Skye lochs – as far as SNH were concerned – was pretty well zero.

When a bunch of us met SNH staff at an exhibition in Kyleakin during preparations for designating Marine Protected Areas, the Small Isles MPA in particular, we asked what they knew and told them what we knew. When assisting SNH with a seashore survey prior to work on the embankments along the Kyle to Strathcarron railway line I was instructed to look specifically for seagrass (Zostera marina) maerl (Phymatolithon calcareum) and crofter’s wig wrack (Ascophyllum nodosum ecad. Mackeii).

If we had not attended that exhibition, SNH would likely have overlooked south Skye as ‘unknown’, don't worry. Until we mentioned it, the SNH people had no idea at all that Loch Eishort had seagrass beds and were only vaguely aware that there might probably be maerl present – they knew not where. Their focus of attention seemed to be oysters (Ostrea edulis). I have no idea why they are considered so important while other species, which are much rarer might well be much more important. Perhaps it’s because they can identify oysters? Anyhow, they became very interested when we told them there were oysters in Loch Eishort, but we had to tell them where to look for them. This they did during the survey they at lasy decided was necessary. According to their blog they had a very good time doing it. It was also a very good survey.

Perhaps because of our insistence that biology in the south Skye lochs was of the highest quality SNH were persuaded they should at last have a proper look at the place. During June 2014 they launched a RIB with drop-down cameras and took photographic 'samples' all over Lochs Slapin and Eishort. The weather was fantastic for several days, so they were able to make a really good job of this survey and at last we had data from locations throughout the loch system. The results were even more interesting than we had hoped.

However, we should not get over confident, I’m afraid, that these data will do a lot to change SNH’s somewhat dismissive approach to habitats and biodiversity in the surveyors' deskbound colleagues' deliberations on fish farm applications. It would not be too cynical to imagine that the Scottish Government, determined as it is to increase farmed salmon production hugely in order to reach ambitious export objectives, has some influence on the content and ‘intensity’ of their advisors’ responses to applications. It is painfully obvious that SNH does little to stand in the way of fish farm development, an uncomfortable truth once quietly vouchsafed to me by one of their people. Instructions from above!

However, now the council's planning officers seem to be taking a tougher line on some of the environmental objections that should properly be forthcoming from SNH. One striking outcome of the latest bid from Hjaltland to place a fish farm in Loch Slapin was the planners’ decision that the Burrowed Mud habitat is a more important conservation issue than was the opinion of SNH; that is, the Highland Council overruled a decision made by their own advisor SNH. [See  below: “...we advise that the area ...".] Well done them. Incidentally, the council is also beginning to suggest that the fish farm companies should start considering a change of practice to closed containment. Once again, well done and thank you the Highland Council.

Burrowed Mud Even the sea bed where Hjaltland proposes to install fish farms in Loch Eishort has value and is not, as SNH has overtly judged, expendable. SNH may have published that judgement but I heartily disagree.

“...we advise that the area which is likely to be affected by this proposal would not be considered of regional or national importance.” – SNH, statutory consultant response to Loch Slapin planning application (Hjaltland Seafarms: 14/01467/FUL)

I do not claim that they are wrong and I am right, but of course, after informed analysis that might turn out to be the case.

The habitat in question does not sound particularly appealing, entitled Burrowed Mud with Sea Pens and Other Megafauna and given the code SS.SMu.CFiMu.SpnMeg. The sea pens are fascinating colonies of polyps, not entirely unlike corals, and the other megafauna includes some extraordinary worms and burrowing sea anemones and Nephrops norvegicus, AKA ‘scampi’, ‘langoustines’, or in the Highlands, ‘prawns’.

Burrowed Mud is not just gloopy goo on the sea floor, it’s a lot more than that. This mud is a complex habitat that supports an array of fascinating specialised creatures, some of them quite rare. The habitat itself is also relatively rare in Britain, mostly occurring in the sea lochs of the Western Highlands. It has been designated a UK Biodiversity Action Plan Priority Habitat and is considered by none other than SNH to be a Priority Marine Feature, so why do SNH consider that it can be sacrificed to degradation or destruction by the deposition of fish farm effluent (which is everything the caged salmon excrete)?

There is a striking coincidence between the geographical and environmental location of salmon farms in Britain and the Burrowed Mud habitat, noted not only by me, but also by the Scottish Aquaculture Research Forum. So when SNH and SEPA sanction the installation of net-cage salmon farms in practically every suitable inlet in the West Highlands it is concurrently allowing localised, probably also widespread, pollution of this entire rare habitat. Subtle ecological degradation effects will pass unnoticed by land-based humans, although they will be significant for communities of sea bed organisms. Once every patch of Burrowed Mud has its fish farm we will probably never know what degradation has occurred there because we have only superficial ecological information about the habitat in its original healthy state.

Pollution controls regulated by SEPA account for noticeable local effects (by-and-large accepting or overlooking them) and ignore implications from research that the impacts, of eutrophication in particular, are probably much more widespread than has been assumed over the years. Meanwhile, independent scientific research has tended not to focus on the subtler environmental impacts of fish farms. There has been, however, research into ecological effects of eutrophication in different situations with nutrient loads not of fish farm origin, that can be interpreted to imply grave unforeseen problems more distant from fish farms than is usually considered.

This is worrying. Our statutory controllers of fish farm activity, apparently with little or no reference to peer-reviewed research findings, take a remarkably lenient approach to fish farm activities that demonstrably pollute the sea and sea beds which lie in the submarine realm, mostly beyond detection by the general public.

Maerl Beds Maerl (Phymatolithon calcareum) is a small purple-red seaweed that accumulates calcium carbonate, building itself a hard, chalky skeleton. The live plant forms drifts on the sea bed to as deep as the blue-green light it need to photosynthesise will penetrate, while dead fragments wash up to form beautiful beaches of fine white gravel, commonly but erroneously known as ‘coral’.

The submarine live beds [SS.SMp.Mrl] are full of pores and cavities where a host of sea creatures build their homes, hence maerl is considered a habitat as well as a species. The beach deposits are also very porous so that they too accommodate a wide diversity of species. Both habitats are rare and worthy of careful conservation, so when fish farm effluent threatens, mitigation is essential. Scientific attention to the interaction of net-cage fish farms and maerl has been considerable, yet not comprehensive. Research has tended to concentrate on sedimentation impacts, which beneath cages is profound, total, and measurable to distances in excess of 100 m. Sedimentation stifles and kills sensitive organisms, i.e. the ones there before the fish farm arrived.

However, dissolved nutrients can travel far, albeit progressively diluted, and their concentrations increase as sources of them (e.g. fish farms) proliferate. Specific fish farm impacts have received less attention from independent researchers than from the regulatory authorities who are not independent of government pressure to facilitate the activities of industries that benefit economies. Indications from independent research into ecological impacts of eutrophication – nutrient loading – strongly indicate that detrimental changes will occur as concentrations of dissolved compounds of nitrogen and phosphorous increase, even subtly. N & P are, of course, major components of salmon faeces and acknowledged causes of highly undesirable eutrophication on land and in water.

These environmental impacts can be overlooked by hard pressed regulators under persuasive pressure from their political overseers rather than from an under informed, under engaged public. If, once informed, our opinion differs from that those who act on our behalf, we must rectify that imbalance by intensive lobbying. It has been intriguing to note how, as out knowledge and understanding of the salmon aquaculture issue improves, we are able to inform the fish farm regulators – and, to a certain extent, they are listening to us.

Sea Grass Beds Common seagrass or eelgrass (Zostera marina) [LS.LMp.LSgr] is a relatively rare flowering plant that is one of just a handful of species that live entirely in sea water, spending most of their time submerged. Being a green photosynthesising plant it is restricted to shallow water because light at the red end of the spectrum travels only a short distance down the water column before getting absorbed.

Zostera is rare because populations have recovered in Britain only partially following a worldwide blight attack in the early 1930s before which it was much more widespread. One of its main favoured growing media is maerl gravel, so maerl and sea grass beds are usually the same thing.

The south Skye lochs have significant areas of maerl in both Loch Slapin, from Glasnakille to Kilmarie and between Suisnish and Camas Malag, and Loch Eishort at Tarskavaig, adjacent to Eilean Gaineamhach Boreraig and, of course, around the wonderful, accessible ‘coral islands’ north-east of Ord. We know of seagrass beds at Tarskavaig and Ord and in addition we have found washed-up shoots and leaves of seagrass on beaches far from there, indicating that other sites have yet to be found.

Independent research reports strongly indicate that sediments from fish farms can severely affect maerl and increased nutrient levels can cause the retreat and even demise of seagrass. We must not stint in our efforts to persuade SEPA and SNH that there are habitats in Loch Eishort worthy of their attention and conservation.

Boulders A fourth UK Priority habitat is found in places all around the margins of the lochs: Intertidal Boulder Beds, on the low shore covered with saw wrack Fucus serratus [LR.MLR.BF.Fser.Bo] and farther out in the kelp zone [IR.MIR.KR.Ldig.Bo]. Sometimes the boulders are embedded in the sand where conditions become anoxic and inhospitable to anything other than anaerobic bacteria. Elsewhere, their undersides remain open or boulders are piled on top of one another and the cavities there are full of fascinating invertebrates. When we turn the boulders to have a look (carefully replacing them as found when finished) this is where we find the rarest of crabs and fishes, sea squirts and worms.

The Rocky Shore Bedrock is the foundation of a major marine habitat all around the south Skye lochs. If we follow it down from the high water mark we see changes in the occurence of seaweeds and animals, all zoned according to length of time spent out of the water (alternatively, submerged) between the tides. I won’t name them all here, but if interested you can identify them for yourself using my User-Friendly Seashore Guide and Highland Seashores for All. Ecological studies take a lot of time and effort than basic identifications, but a lot can be learnt from them that might be relevant in fish farm debates.

When visiting two particular rocky shores to find out what the shore was like adjacent to proposed fish farm sites off Stac Suisnish and below the cliffs between Tokavaig and Tarskavaig, I have been struck by their supreme qualities. The water draining off the rocks and in the rockpools is unbelievably clear and the seashore life there impressively diverse and conspicuously healthy. Comparison with other places visited and studied – for instance, Millport, location of one of the world’s most famous marine biology stations – leaves one deeply impressed by the sheer quality of south Skye’s seashore biology. Sorry, Millport can’t hold a candle to it and Robin Hood’s Bay (where there was once a marine research establishment) is not even in the competition.

Thoughts Certainly the Highland coast has cleaner water than in much of the rest of the UK and clean waters abound here. That’s what the fish farm companies are looking for, not to care for it but for ruthless exploitation. Their captive salmon will not thrive in even slightly polluted water. That’s why some fish farms disappear after a few years, having ‘deposited’ on their own doorstep and turned the 'pristine' waters about which they boast in PR unpristine. SNH dismisses fish farm impacts on Burrowed Mud as trivial and, therefore, allowable. It will have to think twice before taking a similar attitude towards maerl and seagrass beds, both of which are in their remit for protection when development threatens. However, the apparently widespread or commonplace rocky shore habitat has no designation or conservation status and will likely be dismissed as ordinary and, therefore, dispensable.

I was once inspired by an article by Richard Mabey in which he made a case for conserving the ordinary. The rocky shore might be considered an ordinary habitat and we must robustly contradict all judgements that dismiss it as dispensable when economic needs are pressing. Our entire planet is under pressure to accommodate industry, and natural places are deteriorating or disappearing altogether at an alarming rate. I will not present the arguments here, but I suggest that before long we will regret losing natural habitats and biodiversity. No, ‘losing’ is the wrong word because it implies that we have a passive role in their disappearance. We are actively causing habitat losses and so we must accept the responsibility or oblige those who are causing the natural world to deteriorate to take theirs (hold their feet to the fire). Polluting fish farms are incompatible with places like Loch Eishort and it is up to us, the public, to say so in the presence of those who consider themselves to be in charge. Loch Eishort has visible scars (from fosrestry and wild fire) if you know where to look. Submarine scars will be less obvious until they fester in the form of, for instance, toxic algal blooms. To a certain degree, we can predict such deterioration and simply must not permit it.

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