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There I was sitting, thumbing through the latest copy of Tanked Up and under the title of “Some fish farming can offer a sustainable, high welfare alternative to over-fished wild stocks. It’s OK to eat the following once in a while”: and there... at number 1 on the list was organically farmed salmon... well, disappointed, that is a word.

My initial reaction was to get onto the magazine website and launch into a diatribe, then I thought that maybe attention could
be drawn to the issue in other ways. As an ex-angler I know the impact that this ‘dirty industry’ has on native wild fish, but would most divers care that much? When you look at the impact, worldwide, of the shark-finning operations, well, divers get upset, but sharks are big, exciting and photogenic. Would people get so het up about salmon and sea trout in west coast rivers and, of course,
a few acres of sea-bed, decimated but in rarely dived sea lochs.

So firstly, why does salmon-farming have such an environmental impact? Well, in a word, filth, yup, crap, excreta, dung, shite, call it what you will if you put a large amount of fish together you get... a large amount of waste and where does this waste go? Let me tell you dear reader, directly under the cage onto the sea-bed, where, over time it
is chemically converted from toxic ammonia based products first to very toxic nitrites and then to not so toxic but as environmentally damaging nitrates. This chain of events is relatively simple and easy to understand, the ammonia based products and nitrates causing things that can move... to move and things that can’t move to die. Blunt, but true, then the nitrates encourage an algae explosion...

What else? Well with such a large mass
 of fish living in such close proximity the prevalence of disease and fish lice cannot be understated. There are millions, and I mean millions of these little devils and whilst the regular chemical dosing of the ‘organically farmed’ salmon keeps the levels acceptable on the farmed fish the immature smolts which need to swim past the cages to reach the sea are infested and quickly die.

The impact of salmon farming is well known and a major topic of conversation in Scottish angling circles, what will be done? Well, without the direct intervention of the Scottish Executive, nothing, not a jot!

Well, all of this is very interesting, but as I pointed out, not much interest to the majority of divers based on the area and the subjects. However, if we expand the topic to look at associated impacts and bring seals into the equation... ah, dear reader, I see that your interest is picking up.

The salmon farming industry has a virtual carte blanche to cull seals as it considers necessary and appropriate. So having removed the natural food source of these aquatic mammals due to the impact of their dirty industry and replaced it with local high concentrations of fish they then cull the seals which come around looking for food to replace their usual diet...

So you have seals which have quite happily lived in a balanced state with the various fishermen and anglers for years, all catching and taking mature salmon and sea trout which are returning to their native rivers to breed. That was a bit tongue in cheek as seals do get blamed when the catch goes down, but that’s just the way of things, I could digress into off-shore factors affecting the size and amount of salmon returning to spawn, but that is not really the reason for this note. The reason for the article is that salmon farmers, having removed the food source for the seals. then kill them...

What does this mean to divers? Firstly if we consider that the impact of salmon farming affects most salmon rivers that enter the sea on the North-West coast of Scotland and that seals travel up to 100km to forage, then this will lower the number of seals present on a huge swathe of UK waters. Additionally, seals learn. They will learn to associate humans with death, so will avoid humans. It used to be a bit of a joke around the Farne Islands that seals ‘could hear a rifle being cocked at 300 yards and be in the water before you could pull the trigger’.

All this means less seals and those remaining will not interact with divers, so the underwater meetings, so common on the Farne Islands will not be repeated on the West coast... certainly until long after the culling has stopped.

So, does salmon farming offer a sustainable, high welfare alternative to overfished wild stocks? That’s up to you to decide, my own thoughts are that it is not sustainable, there are certainly no welfare considerations for the environment and the wild stocks are seriously affected by the farming methodology. But this issue is between you and your own conscience... personally I will not support this industry and actively inform people on just how bad they are.

For additional, albeit angling based details on the impacts of salmon farming, I would suggest that you view a site run by Bruce Sandison, look, think and act.

Richard Wright

Well, as a chef I have one view, and as a diver I have a second. I tend to see both sides of the argument on matters such as this. I agree completely that fish farming (organic or otherwise) is very detrimental to the environment, however the fact remains, the oceans cannot support our current demand for fish on their own. Until such time as global fishing policy is changed, we rely on farmed fish to satisfy demand. Fish farming happens, and it isn’t going anywhere soon - but I do agree that we should not fuel this industry any more than we need to.

Andrew Maxwell

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