Famously the dodo, then the American carrier pigeon. I don’t know how many species a year are driven to extinction by humankind, but there is another one coming. Despite great efforts over the last 50 years, despite international collaboration, despite increasingly sophisticated research and the raising of awareness of the plight of possibly the most important species on the planet, numbers of Atlantic salmon continue to freefall towards extinction.

While we know what some of the issues are, we need to find the missing pieces of the jigsaw urgently. We need to prove beyond doubt our theories and assumptions; and we need convincing analysis of scientific data to take to the national and international policy makers.

If you brought together all the dinner table conversations of fisher folk – anecdotal in the main, but informed by a lifetime of experience – there would be a colourful collection of strong opinions on this decline. It sometimes grates to listen to someone bang on about a blank week being absolutely the fault of a Japanese trawler scooping up the entire grilse run of three Scottish rivers in a oner without any reference to the wider context, habitat, climate etc. As guilty as anyone, I have pointed the finger at commercial forestry for years, banging on about the ecological black holes that are upland catchment plantations, but could I prove it scientifically? It seems glaringly obvious to me, but I must concede that this localised problem doesn’t explain declines where no commercial forestry is present.

Anecdotal opinion is almost entirely based on recent history. If you ask people when they think the most dramatic decline of salmon occurred, they generally think it was the 1960s to 1980s, but it still seemed there were enough to go around. We soak up the stories of great catches from our fathers and grandfathers, retired ghillies and their forebears, friends who knew the netsmen on the Tweed.

One such tale involves my friend who farms 10 miles upriver from Tweedmouth, who got a knock on the door at 2am from the netsmen, asking him to bring his tractor to pull up the net as it was so full of fish. On all rivers that held salmon you’d hear how every little feeder burn, as well as the main river, was full of hundreds, thousands of pairs of spawning fish, their gravel redds clear to see in late autumn. You would hear about great rafts of shoaling smolts making their way down to sea in April, the water’s surface sparkling with tens of thousands of juvenile salmon stretching the width of the river and hundreds of yards long for several weeks.    

So what happened? Well, the following is a collection of top suspects: the contributory factors that many of us believe are causing the decline of Atlantic salmon, whether that’s local to a particular river or internationally.

Commercial afforestation Along with the associated drainage, this has a profound negative ecological and geomorphological effect on many river systems in the UK, especially where sensitive upland catchments have been planted. Problems include: dramatic changes in river flows, increased run off, flash flooding, erosion, siltation, diffused pollution from eroding peat, removal of the smaller gravels and substrates vital for spawning, widening, shallowing, heating up and braiding of upland nursery habitats. Together, these reduce water retention for slow release from what used to be the great sponges in the headwaters – and result in roaring spates that last a few hours before dropping back to a black trickle of summer water.

Agriculture The chemical and fertiliser run-off from intense arable and livestock farming is well-documented. These practices pollute waterways with insecticides and herbicides, enriching them with nitrogen fertiliser, cause the depletion of insects and biomes, and allow drainage from farms and subsequent soil erosion to pour into our rivers, coating the riverbeds with filth, and creating blooms of blanket weed and algae that suffocate and deoxygenate the water.

Pollution and extraction We have all heard about the water companies dumping raw human sewage into our rivers. Even the clean stuff will have traces of medicines, cocaine, e-numbers, and other chemicals. You can add to this the billions of tonnes of plastics, diesel, salt from the roads,cement – the list of stuff that ends up in our rivers is endless. Then there is the extraction of water for farming, hydro and industrial use, further reducing the amount of water in our river systems – seriously, it is a wonder that any living thing remains in any river in Britain, or the rest of the world for that matter.

Aquaculture Salmon farming is locally devastating to the west coast of Scotland, with any wild smolts having to pass through curtains of sea lice and seabed pollution. Disease- ridden escapees looking to interbreed weaken the genetic integrity of the wild fish. While the rise of salmon farming in the early 1980s is labelled as the reason for the collapse of the west coast salmon and sea trout fishery, the practice of sea bed dredging for molluscs (scallops, razor clams, etc) since the removal of the coastal protected zone in the ‘80s has rendered thousands of acres of sea bed devoid of life, such as seaweed, shrimps, sand eels or krill. I assume that juvenile salmon need to feed heavily as soon as they hit the sea in order to sustain their journey to the feeding ground but a ploughed-up seabed isn’t going to be the fast food swim-thru it used to be. (See, I’m already honking on about something I know not much about!) The deadly combo of aquaculture and dredging must surely have been a total disaster for Scottish salmon.

Habitat degradation The inexorable development of rivers for navigation with locks and dams, dredging channels, and the straightening and modifying of natural channels had a hugely damaging impact on salmon numbers. The Kielder dam on the North Tyne, for example, chopped off 90% of the spawning grounds. Work is being done now to resuscitate this once great salmon river, although it is still a mere shadow of its former self.


Like many others, I always thought that the decline of Atlantic salmon was a post-industrial revolution problem, only affecting those rivers in industrial hubs. The Tyne river system was brought back from the brink twice in 100 years: spectacularly by the Salmon Fisheries Act of 1862 opening up the dams and obstructions in the main river and tributaries, which led to huge increases in numbers, and then again after a restocking programme was put in place after the Kielder dam was built in the late 1970s. But it is not self-sustaining, relying on its North Tyne hatchery. In fact looking back I hadn’t really considered beyond what I thought of as ‘salmon rivers’ – the likes of the Tweed and the Tay, and the smaller Esks, Naver, Helmsdale, etc. I rather thought that the Ouse, Thames, and Trent types were coarse fish rivers and always had been.
But here’s the bombshell.

In researching for this article, I came across a fascinating paper by several learned Europeans (Lenders, Chamuleau, Lauwerier, Leuven and Verbeck) about the rise of water power across Northern Europe and their theory that this led to the significant decline in the range and number of salmon from the early Middle Ages, around 900 AD!

The article related primarily to the Palaeo-Rhine basin which refers to the collective area into which, many moons ago, when Britain was connected to Europe, poured the Thames, Meuse, Seine, and Rhine rivers to form a serious salmon river flowing south through the Straits of Dover. One might need more than a Hardy Sintrix loaded up with a Mckenzie integrated shootin’ heed for that stream.

Their theory, based on research of salmon archaeological remains and historical documents, is that the decline of salmon started much earlier than we thought. From the turn of the 1st century, the use of water power mills saw a sharp increase of dams and water wheels up the lengths of many rivers. In William the Conqueror’s 1091 Doomsday Book, there were already nearly 6,000 water wheels listed. Dams and water wheels significantly alter the geomorphology of a river and as regards salmon, the dams reduce flow, create siltation, impede access to spawning grounds, and make exploitation of the salmon rather easier. Water power throughout Europe and Britain increased dramatically through the 13th, 14th,15th and 16th centuries, with some rivers having up to 10 dams and water wheels per kilometre. As methods of building dams and wheels improved so they became bigger, more numerous and more impassible for migratory fish. By the end of the Middle Ages, the paper suggests that salmon populations across northern Europe had fallen by 75%. By the end of the 18th century, affected rivers had lost 95% of their salmon.

One example to illustrate the decline was a Medieval salmon fishery at Montchaton in France. In the 14th century it took 350 to 400 salmon a year. By the end of the 15th century it was down to three or four a year! The price of salmon in Europe was very high by the mid-1700s because most of the fish were imported from Scottish and Norwegian rivers, which were faster flowing, more difficult to dam for power and still enjoying the annual silver harvest. The old story of apprentices’ contracts in London stating they were not to be fed salmon more than twice a week must have been in the Middle Ages rather than the 18th century, as by then the Thames had no salmon left either.

A rough estimate puts the population of Atlantic salmon in Roman times at between 100 million and 150 million. The river Rhine may have had runs of 10 million plus salmon every year, the Thames 500,000 to 1,000,000. As a pioneering and aggressive species, salmon will populate wherever they can and colonise that river until the maximum holding capacity is reached, but if it can’t head upriver to spawn it’s a sharp route to extinction. Between the year 1050 and 1900, salmon populations in the Rhine, Seine and Thames had declined by 99.9%. Basically, they were extinct.

So when we talk about the recent history of salmon decline we are actually looking at the decline of the last 5%. What we think of as the salmon rivers of today are the last faint bleep of the final life support system for Atlantic salmon.

Then around 1958 the Danes and Greenlanders discovered that the multi sea winter salmon all head for the north- west of Greenland for their feeding grounds. The relatively sustainable Greenlandic fishing of a few thousand fish a year to feed increased to 650,000 salmon netted per annum by the early 1960s. This raid went on for a number of years and it took huge negotiation from the UK, Europe, US and Scandinavia to get the Danes to agree to significantly reduce their quotas. It took another 20 years to reduce the exploitation by our own drift net fishery.

This exploitation of salmon at sea coincided with the advent of monofilament netting. This could be deployed by trawlers for literally miles at a time. The reported north-east England catches went from 10,000 a year to 60,000 and more likely double that including fraudulent non-reported catch.

We still do not know the effects of illegal off-shore trawling. 


Through the tireless work of organisations such as the Atlantic Salmon Trust (AST) and North Atlantic Salmon Conservation Organisation, individuals such as Ori Vigfusson from Iceland, and the understanding and help of the Danes, the Greenland fishery has been largely reduced, the Scottish and Irish drift net fisheries have been bought out, and the river nets on the Spey, Tay, Montrose Basin and Tweed are closed. Just the coastal T nets remain, for sea trout only, and just for a couple of months. About 95% of rod caught salmon are returned and each and every fish is vital.

The sad thing is that there would have been enough salmon if the smaller coastal fishing communities had been left to continue their work responsibly and sustainably.

But work is being done. Our rivers are getting a bit cleaner, and the obstacles to free passage upstream to the spawning grounds have been removed steadily. The catastrophic planting, draining, polluting and overgrazing is slowly being reversed. Tweed Forum is doing amazing work on the re-meandering of straightened streams, slowing the flow, restoring upland peatland and floodplain, and planting native woodland.

More work is needed on spawning habitat, especially where increased water flows have removed the suitable gravel widened the channels for predators. A huge amount of shading and cooling through appropriate planting needs to happen urgently, especially in the overheated riffles of the upper reaches. The effects of climate change on the upland catchments of river systems of Caithness and Sutherland are predicted, in their current state, to be unable to sustain juvenile salmonids by 2050.

Occasionally there is good news. Last year, a salmon parr was found in the middle of Sheffield in the river Don. Two years ago, someone caught a salmon near Paris on the Seine. The Roma in Norway is recovering in style from a parasitic worm called Gyrodactilus Salaris, the entire river having been sterilised three times in the last 20 years. There are still some modest runs in the north and north-east coast of Scotland, even capacity of breeding fish in some rivers – but just when you think there is a ray of sunshine yet another disease will hit a river: red vent, red belly or Ulcerative dermal necrosis (UDN).

Today, the numbers of Atlantic salmon in the UK and north- west Europe are barely one or two per cent of what they were when the Roman legionnaires nicknamed the fish Salar the Leaper. Salmon are extinct in most European rivers and the runs of salmon on even the best managed rivers in Scotland seem to be getting less and less, missing years of grilse runs, with non-existent spring runs in perfect conditions. What is happening to them?

Here’s a sobering thought: there are more cultured salmon in Mowi’s four closed aquaculture tanks (a welcome development we hope) than there are wild salmon left on the planet. The tracking project carried out by the AST seems to show that 50% of juvenile salmon never make it to the sea. Why? Lack of food, lack of biomass, something altered in the riverbed, pH balance, winters too warm and spring too cold? Piece by piece we will build the jigsaw: is it man’s exploitation, is it predators, mackerel, seals, sea birds? Is it food, is it temperature, is it climate change and ocean currents, is it windfarms interfering with the salmon’s navigation. The answers for UK salmon lie somewhere between the top of our rivers and the feeding grounds off Greenland and the Faroes and we must find answers.

If one pans out to a continental view, away from local catchments and river systems and recognise that we have lost 95-99.9% of the entire Atlantic salmon population across Europe it is clear that there is an ever smaller biomass from which a larger and larger proportional bite is taken at every stage. A million or two fish is probably way below the critical mass needed to sustain or grow numbers. As a golden and irreplaceable resource that has sustained us for food and sport for centuries, we must succeed in building up the species internationally across their whole historical range, as far as possible, and not just hope that a few cold clean rivers can act as a fragile life support for a desperately threatened species.