Warm winter puts stocks of salmon at their lowest ebb
SALMON stocks have fallen to record lows in British rivers because of a warmer winter, experts believe.
The Game & Wildlife Conservation Trust said the number of juvenile salmon leaving the Frome river in Dorset for their feeding grounds in the North Atlantic in 2017 was half the 10-year average and the lowest number ever recorded.
Nearly 10,000 young salmon – or smolts – usually leave the Frome in the spring but this year only around 4,300 were counted.
Poor numbers of salmon from the 2015-16 spawning season has been observed in many rivers across England and Wales, suggesting it could be a national, rather than a local, phenomenon.
Dr Rasmus Lauridsen, head of fisheries research for GWCT, said: “The number of young salmon leaving our rivers has a direct effect on the number of adults returning to spawn.
“With adult numbers already at an all-time low, this is worrying data for an iconic and economically important species.”
Experts believe that unseasonably warm weather in the early part of the winter in 2015-16, when the adult salmon were laying their eggs, caused fewer fish to survive.
As a result of the low numbers of smolts in 2017, it is expected that fewer adults will return to the Frome in 2018 and 2019, after they have spent between 12 months and two years at sea.
Falling numbers of the fish are likely to cause supply problems and inevitably push up prices.
Dr Lauridsen added: “This is a stark reminder of the importance of the freshwater stage of the salmon life cycle and its potential to affect stocks in subsequent years.”