Tony Andrews, executive director of the Atlantic Salmon Trust, fears that if we continue on our current course the species may be doomed. He outlines a programme to save the Atlantic salmon.
Atlantic salmon is not only a valuable international resource, it has been at the heart of national cultures of countries in the North Atlantic region for at least 20,000 years. As has catching this most challenging, and often elusive creature. Use the classic salmon fly, after reading about a good number of the best vintage fly tying books. Or watch our video on how to catch a salmon for the best top tips.
The salmon carved in a Dordogne cave and the Glamis Stone testify to its spiritual importance. In Canada and Finnmark First Nation people still regard the salmon as sacred. The late poet laureate, Ted Hughes, celebrated the Atlantic salmon’s life cycle in elemental terms in his poem Salmon Eggs.
ATLANTIC SALMON: NATURE’S BAROMETER
The life cycle of the salmon gives it the status of a “barometer” species, providing detailed information about our environment. Few other fish species are protected by an international treaty organisation. The governments of the Atlantic salmon countries are signatories of NASCO (North Atlantic Salmon Conservation Organisation), of which the International Atlantic Salmon Research Board is a part. NASCO’s existence is a measure of how important the conservation of the wild Atlantic salmon is to the signatory governments. It also has 34 NGO members and access to the best fishery scientists.
Despite this, the wild Atlantic salmon’s future is uncertain. The species is in danger of extinction, perhaps not imminently or everywhere but at least in its southern range. Among the many possible causes for the Atlantic salmon’s decline the most threatening is climate change. The most obvious effect of which is ocean warming. Salmon are cold-water fish. Higher temperatures impact on their marine and freshwater habitats and reduce the abundance of their prey species. The key question is whether human intervention can mitigate the effects of climate change on salmon stocks at sea.
ATLANTIC SALMON UNDER THREAT
Concern regarding the decline of stocks of wild Atlantic salmon by more than 60% in 40 years prompted NASCO to launch the Salmon at Sea (SALSEA) project in 2008. The project’s goal, as explained by NASCO’s Dr Malcolm Windsor, is, “to increase understanding of how salmon use the ocean, where they go, how they utilise currents and the ocean’s food resources and what factors influence their migration and distribution at sea”. Since then, scientists from the North Atlantic salmon countries have made unprecedented efforts to ascertain “where, when and how are such high numbers of salmon dying at sea”.
The Salmon at Sea (SALSEA) project was launched in 2008.
Farther north, other European rivers are starting to record the effects of climate change. In some Pennine and Scottish river catchments, planting programmes have been implemented to protect juvenile salmon from high water temperatures caused by direct sunlight on shallow upland streams.
Studies of effects of drought conditions on salmon waiting in estuaries indicate that up to 50% may die from a range of causes, including high temperatures, predation, coastal netting, salmon farming, pollution and disruption to migrations caused by renewable energy projects. The problems caused by high summer temperatures are also affecting North American rivers such as the Mirimichi and the rivers of Maine, Quebec and Nova Scotia. Severe storms that affect the top layers of the pelagic zone of the ocean’s water column can change surface currents and throw migrations of post-smolt salmon off course.
The Atlantic salmon is an endangered species in the United States. Canadian rivers flowing into the Bay of Fundy historically had annual runs of more than 40,000 salmon, they now have fewer than 200. Portuguese rivers have lost nearly all their salmon, the rivers of Galicia and Asturias are on the edge, as are the rivers of southern France, despite heroic efforts by fishery managers. For example, soon the Allier, a tributary of the Loire, may be unable to sustain salmon; outgoing smolts and incoming adults have to negotiate more than 800 kilometres of the river’s main stem and for most of the year it is too hot for them to survive. As Dr Patrick Martin, the Loire’s head conservationist, commented recently, “The Loire salmon’s migration window is closing.” With that closure the opportunity for the fish to migrate is lost.
Oceanic and terrestrial warming is squeezing the salmon’s habitat at all stages of its life cycle in rivers and at sea.
3 MOST URGENT ISSUES FOR ATLANTIC SALMON
The most urgent issues, in the context of marine mortality and with salmon already extinct in more than 300 rivers, are:
The effects of salmon farming
With a global ratio of one wild Atlantic salmon to 200 farmed fish in open net cages “sharing” the same coastal waters, an uncompromising precautionary approach should apply in licensing such facilities. Parasites, genetic ingression, pollution and disease from salmon farms may affect wild salmon much farther away than the locality of the salmon farm.
Mixed stocks netting
This kills Atlantic salmon from unknown rivers of origin and continues despite international pressure to end it. In 2013, for example, one Scottish coastal net fishery killed 7,159 salmon and grilse, while the total number of salmon killed by nets in England and Wales was 24% above the average of the previous five years. Atlantic salmon swim with other pelagic fish, including mackerel and herring. Some salmon are being accidentally caught up in the nets of commercial trawlers. We need to know the extent of that “by-catch”, as well as where and when it takes place.
Climate change
This must be assessed, particularly in relation to ocean warming, bearing in mind the question, “Is extinction of the species inevitable?” If the answer is yes, what is the timescale? What, if anything, can be done to delay that inevitability? If the answer is no, can we find ways to give the wild salmon time and space for its natural resilience to kick in? There is evidence that salmon have survived massive geophysical and climatic changes, including at least two ice ages. What can be learnt from the historical and current life strategies of the species? Can we find ways of integrating our restoration efforts with that innate resilience?
Most conservation efforts concentrate on rivers. Salmon have been categorised as freshwater fish with a marine migratory phase. As a result, most resources are spent on restoring riparian habitats and studying the freshwater phase of the species’ life cycle. More needs to be known about its life at sea. Already, in Canada, Ireland, Norway and Scotland, new tracking technologies are deployed to determine where it goes and where obstacles to migration exist.
3 STRATEGIES TO SAVE THE ATLANTIC SALMON
If the Atlantic salmon smolt heads to the water off West Greenland to feed what are their chances of survival and return?
A “big picture” strategy encompassing the whole life of the salmon is badly needed. Recent advances in freshwater fisheries management must continue because each river catchment is unique, as are the populations that comprise its stock. Their survival depends on genetic diversity. Atlantic salmon countries must plan on a larger scale than hitherto on the following bases:
- Continuing to improve freshwater productivity through river catchment, ecosystem-based assessment, monitoring and actions.
- Using a precautionary approach to demand proof that new engineering projects along the coasts and in the ocean do not harm the en-vironment. Issues such as by-catch, renewable energy, poaching, salmon farming, coastal and drift netting and pollution are a starting point.
- Mapping migration routes and attributing populations to regions and even individual rivers should enable scientists to predict future abundance or otherwise. Appropriate management action can then be taken in real time, as already happens to some extent in Ireland, Canada and Norway.
The “big picture” strategy requires a new international effort and level of cooperation. Large amounts of private sector money from the salmon countries of the North Atlantic region will be needed to pay for research and monitoring at sea. The process of mapping out safe migration “corridors” and, through NASCO, negotiating international agreements to protect salmon at sea, must follow.
DO RECENT CATCHES TELL THE WHOLE STORY?
Fishing for Atlantic salmon. Will this scene become extinct? Rod catches are down.
Rod catches in many fisheries of the North Atlantic countries have been among the lowest ever recorded. In some rivers in North America, Iceland, Norway, Ireland and the UK, rod catches in 2014 were lower than the five-year average. The main exception was Russia’s Kola Peninsula, especially Barents Sea rivers, where both the numbers and quality of salmon are holding up well.
But, do rod catches provide reliable data for stock assessment? The situation is more complex than might at first appear. For example, in 2014 spring salmon, returning to some Scottish and Irish rivers after two or more years feeding at sea, were caught in reasonable numbers and were in excellent condition. Ireland’s River Slaney, for example, had its best spring returns for 30 years, with most fish in prime condition and weighing 12lb to 15lb. A similar spring season was enjoyed by rods on some Scottish east coast rivers. Nearly all these fish were caught and released, while coastal netting was delayed until April.
Later in 2014 low-water and high-temperature conditions in many North Atlantic rivers did not favour high rod catches. Grilse returns in European salmon countries were, at best, variable, in some cases virtually non-existent. There is also evidence that extreme flooding in the wake of Hurricane Bertha reduced juvenile density considerably in some Scottish upper catchment tributaries.
Some freshwater fishery managers are saying that little can be done to improve the situation at sea, so efforts should be stepped up to improve freshwater productivity. However, while that view is understandable, it does not address the fact that more than 90% of wild Atlantic salmon are dying at sea, whereas only 40 years ago the figure was more like 65%.
If the number of smolts that survive to become adults could be increased by only 2% or 3%, there would be significant difference to the quantity of adult fish in our rivers.
3 PROJECTS TO BRING BACK MORE ATLANTIC SALMON
Three projects to bring back more salmon to our rivers are listed below. Funds are urgently needed to implement them. We cannot predict the increase of returning salmon but we can state that these projects are a practical starting point, with more projects to follow as knowledge of migrations improves.
By-catch
This innovative eDNA pilot project addresses the issue of accidental by-catch by pelagic trawlers. By employing forensic methods routinely used at scenes of crime it can determine whether salmon DNA is present in body fluids on the decks or nets of the giant pelagic trawlers. Our concern is the likelihood that post- smolt migrations, relatively densely packed within coastal currents, may be inadvertently caught up in huge purse-seine nets. It is conceivable that the entire migration of a small river could be wiped out by pelagic trawlers.
Coastal waters
There is a high risk of smolt mortality in the days after they enter the sea, which may cause huge variations in adult return rates. Research is urgently required to establish where and how smolts die in the coastal zone. If we can identify the extent of the loss and the causes we can develop remedial actions. Return adults are also at risk in estuaries, where it is thought that up to 50% may die in adverse conditions.
Migration corridors
Establishing protected migration corridors for salmon between their native river estuaries and their feeding grounds requires a co-ordinated international effort. In the longer term this approach may prove to be the most effective way to bring more salmon back to their native rivers.
The effects of losing the salmon would be a disaster. Recent surveys in Canada, Scotland and England show that the wild Atlantic salmon is often central to rural economies. Salmon fishing tourism provides income and jobs for remote communities and gives them a strong sense of identity.
As food, driver of rural tourism, angler’s quarry or cultural icon, the existence and value of the wild Atlantic salmon has never been fully appreciated. To allow its demise would be a human catastrophe. Continuing as we are is not an option.