Picture this: you, mouth watering, have just loaded a delightful forkful of pink, flaky goodness, soon to be delivered to a grumbling stomach. You are stopped, however, by a rudely interrupting thought. Where has this salmon come from? What am I actually eating?
Unless you paid an awful lot for your salmon, it is likely to have come from a salmon farm and what you are eating is an imposter, a genetically warped substitute. The reason for this is that wild British Atlantic salmon stocks are freefalling, a population wasting away towards local extinction. If we’re not careful, we could see the last of these iconic fish in our rivers in our lifetimes, and that is a deeply worrying thought.
Why we care
You should care about wild Atlantic salmon. Even if you’re not an obsessed middle-aged flat cap wearer with a £5000 a year salmon fishing budget. Salmon have been of cultural importance to Britain for centuries, featuring in popular culture of all forms, from the literary works of Izaac Walton and Henry Williamson to film, television and poetry. It is a species that captures the imagination.
It is also a species of huge economic value. The Environment Agency for England and Wales found that anglers spent over £7 million in 2015 on salmon and sea trout fishing alone (1). In theory, this is an industry that can be sustainable, providing rural jobs and incentivising river conservation. In addition, there is growing evidence for the ecological importance of salmon for rivers as a keystone species – a species with a fundamental role in the functioning of an ecosystem. The impact of losing salmon on the health of our rivers is understudied and still relatively unknown.
Besides all this, it is an animal with an aura of natural mysticism. An iconic species that encapsulates the wild and immutable nature of the river. In a landscape that has been tamed and exploited for centuries, animals with this mystique are crucial for us to maintain our connection with the world we inhabit. For inspiring generations with that element of the unknown, the inexplicable, the flash of silver seen fleetingly and never again.
Sliding towards extinction
The unfortunate reality is that said flash of silver has already disappeared from much of its Southern range. Local extinctions have occurred across historical European fisheries and in Southern England, some UK extinctions have already begun.
Annual assessments of the status of salmon stocks from the ICES Working Group on North Atlantic Salmon (WGNAS) paint a picture of overall decline across the North Atlantic range, whilst the Environment agency described 88% of the principle English salmon rivers as having “at risk” or “probably at risk” salmon stocks (2).
The scale of environmental action undertaken to support salmon conservation is enormous. From reducing pollution to removing migration barriers, a huge amount of work has been done on rivers to provide adequate inland spawning habitats. The problem, however, is that even the most pristine freshwater ecosystems are still suffering declines, an issue that relates to the salmon’s extraordinary lifecycle.
Atlantic salmon are mostly diadromous, meaning they migrate between freshwater and saltwater environments. Salmon develop in freshwater streams and migrate to sea, growing larger than the river environment could ever facilitate, before invariably returning to the exact same stream to spawn. Remarkably, oceanic migrations have been found to reach distances of over 4000 kilometres (3). Along this extraordinary migration, salmon are facing a huge variety of threats across massive geographical ranges.
Threats, threats everywhere!
Recent scientific literature has attempted to evaluate the major threats to wild Atlantic salmon. In a study of particular problems for English stocks, across the range of stressors assessed, climate change and predation were highlighted as the most threatening (4). However, in a separate study, considering the entire North Atlantic range, the significance of climate change for salmon declines was questioned. This study’s findings concluded that unregulated fisheries exploitation at sea was likely the major cause of systematic, cross-continental declines (5). These papers were both published in the last two years, highlighting a central issue for salmon conservation: we still don’t really know what’s going on.
The resilience of the species to environmental pressures is dependent upon genetic variation within the population. This in itself is threatened. In part by the introduction of the imposter, the farmed Atlantic salmon – a genetically artificial mutant, which inevitably have found their way into the wild population. The threats are expanding, the resilience is declining, the species is disappearing.
The End of an Era
It is clear we are losing something special, a key component of this country’s natural heritage. The stats suggest that despite our best efforts, this decline isn’t letting up. The key to finding the solution is to fully understand the causes of the decline, a task that has proved incredibly difficult in the face of a great variety of threats, across a huge geographical scale. As we lose this iconic species, in our increasingly urbanised country, the image of the salmon is changing in the public psyche. Gone is the leaping bar of silver, defying the odds of the raging river, a symbol of the wild and the untamed. In its place is the Tuesday night special, the high-protein pink superfood, another case of the world warped to our tastes. So, next time you load that fork, spare a thought for the lost king of freshwater fish.
References
- Environment Agency (2018) A Survey of freshwater angling in England. Environment agency, Bristol.
- Environment Agency (2020) Salmonid and fisheries statistics for England and Wales 2019
- Bradbury IR, Lehnert SJ, Messmer A, Duffy SJ, Verspoor E, Kess T, Gilbey J, Wennevik V, Robertson M, Chaput G, Sheehan T. Range-wide genetic assignment confirms long-distance oceanic migration in Atlantic salmon over half a century. ICES Journal of Marine Science. 2021 Aug;78(4):1434-43.
- Gillson JP, Bašić T, Davison PI, Riley WD, Talks L, Walker AM, et al. A review of marine stressors impacting Atlantic salmon Salmo salar, with an assessment of the major threats to English stocks. Reviews in Fish Biology and Fisheries. 2022;32(3):879–919.
- 1. Dadswell M, Spares A, Reader J, Mclean M, Mcdermott T, Samways K, et al. The Decline and Impending Collapse of the Atlantic Salmon (Salmo salar) Population in the North Atlantic Ocean: A Review of Possible Causes. Reviews in Fisheries Science & Aquaculture. 2022;30(2):215–58.
The Quagga 