– It is completely tragic. There is a great danger to the wild salmon population in Namsen. That’s what Jenny Kjestveit Domås says, landowner, shareholder and board member of Norske Lakseelver. She is talking about the new report from the Norwegian Institute for Natural Research (NINA) and the Marine Research Institute (HI). They have looked at genetic changes in 250 salmon populations. Together, these represent 95 percent of all wild salmon in Norway. The data material consists of salmon caught in the rivers, after escaped farmed salmon have been weeded out. Major genetic changes have been found in 31 per cent of the stocks. – The consequences for wild salmon are that crossbreeding with farmed salmon makes them less adaptable to nature. We have done several experiments and found that the offspring of farmed salmon generally survive worse. That’s what Kjetil Hindar, senior researcher at NINA, says. – We have also seen that they change characteristics – they grow faster in fresh water and enter the sea younger. And they grow faster in the sea and return to the rivers younger. Its whole life goes a little faster, and it returns to the rivers as a slightly smaller salmon than the wild salmon. The salmon stocks are divided into four levels of condition. Graphics: Monica Ruano, NINA “Queen of Salmon Rivers” Moderate to large genetic changes have now been detected in 98 salmon stocks. This corresponds to 39 per cent of all stocks – an increase from 32 per cent from the first classification in 2016. Among the watercourses that have been given a worse status since the previous classification, we find Namsen, one of Norway’s largest salmon stocks. The “queen of salmon rivers”, as Namsen is called, has suffered the worst condition: Very bad. – And this has been going on for a long time, so this is something we have been concerned about and said about for a long time. Now we see that it has had consequences, says Domås. Domås is disappointed that Namsen has gone from orange to red level since 2016. Photo: Eivind Aabakken / news Lærdalselva, Stjørdalselva and Repparfjordelva have also been downgraded to very poor condition. – What could that mean? – It has been documented that wild salmon with farming genes have poorer survival. In the long term, and already, it will lead to a reduction in the stock. – And once you’ve got the farming genes in, it will be carried on, so it’s difficult to clean it up. About the calculations When the Quality Standard for wild stocks of Atlantic salmon was established, the Norwegian Institute for Natural Research (NINA) and the Institute of Marine Research (HI) in mission to calculate the extent to which escaped farmed salmon have crossed into wild salmon populations. In 2016, 125 salmon stocks were classified with regard to genetic crossing of farmed salmon with wild salmon. Three subsequent reports have classified 175, 225 and 239 wild salmon stocks respectively, including all National salmon rivers. Want closed facilities Domås believes that the only solution to be sure that farmed salmon do not escape is to get them into closed facilities. – Then you will also get rid of the problem with lice. Kjetil Hindar in NINA also thinks so. According to him, if the wild salmon is to have a future, farming must be based on closed technology. – The wild salmon has many other threats. The fact that it is genetically less adapted contributes to making the situation even worse. Over time, this will lead to fewer salmon. – And for all these rivers that have large incomes from salmon fishing, this means poorer and poorer incomes. In all the waterways that end up in red, you have to expect restrictions on fishing. Moderate to large genetic changes have now been detected in 39 per cent of all salmon populations. Photo: Knut-Sverre Horn Some improvements In 32.8 per cent of the rivers no genetic changes have been observed. There are weak genetic changes in 28 per cent of the populations, while moderate genetic changes have been detected in 8.4 per cent. The clearest improvement has been found in Eastern and Southern Norway, in areas without, or with little, salmon farming. Large watercourses such as Numedalslågen and Skiensvassdraget are now in very good or good condition. The 54 waterways that are defined as National salmon waterways have a slightly worse status than the other stocks. Here, moderate to large genetic changes have been detected in 44 per cent of the salmon rivers.
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Major genetic changes in one of three wild salmon populations – news Trøndelag – Local news, TV and radio
