A race to save Atlantic salmon from extinction is heating up.
A massive research project in the Highlands will ultimately shape policy aimed at reversing a trend and increasing stocks.
Scientists and river managers work together knowing that salmon numbers are barely a quarter of those recorded just 40 years ago.
Experts classify the emblematic species among the great barometers of nature, to measure the health of an entire ecosystem.
Scientists and river managers are midway through the third and final year of a research project to determine why salmon stocks have fallen by perhaps 75% since the 1980s.
Project designer Dr Angus Lothian said: “It’s a complex set of reasons, not just any.
“It’s not just predation, it’s not just water extraction. It’s not just about barriers to migration. It’s all of this and more really being brought under control by climate change.
“Everything just goes in the wrong direction for the salmon.”
A team effort is plunging deeper than ever into a crisis that the Missing Salmon Alliance says has seen salmon stocks drop from eight or ten million 40 years ago to possibly two million.
The focus is on the migration from the river to the ocean, and vice versa. Early results suggest that half of the smolts – young salmon – are now ‘missing’ as they swim down the river.
Scientists visit traps in the Highland River every day to take scale samples from fish and tag them with tiny, surgically inserted acoustic transmitters.
The beacons are then detected by receivers placed along the river during their migration and the receivers holding the data will be recovered in June and July.
Roger Knight of the Spey Fishery Board said: “The situation is really very worrying.
“Climate change projections point to the very low water conditions we had in 2018, when we saw Spey fall to its lowest level since the 1976 drought.
“This situation is expected to happen every two years by 2050, unless we do something now.”
Simply put, salmon need cold, clean water. If the current trend is not reversed, the Missing Salmon Alliance of frontline organizations predicts that Atlantic salmon will disappear from our waters within 20 to 30 years.
Asked what the public can do to help, Mark Bilsby of the Atlantic Salmon Trust said: ‘It is recognized that salmon are truly in crisis and this is the first step in a recovery plan. We need to take these steps, but we need proof. There is no point in showing up with an opinion.
“However, we have seen a big movement in people over the past few years.
“They recognize the value of iconic species such as salmon and how they are an important part of our landscape and the biodiversity around us.”