Climate change, warming seas and pollution all factors affecting population of Atlantic salmon across rivers in the UK
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Atlantic salmon stocks in England are at an all-time low, according to a new report from the Environment Agency and the Centre for Environment.
The 2023 Atlantic Salmon Stock Assessment shows that four out of 42 rivers experienced a decline from 2022. Forty years ago, 1.4 million salmon returned to UK rivers each year. Today, this figure sits at below 466,000.
Ninety per cent of principal salmon rivers in England are now classified as either ‘at risk’ or ‘probably at risk’, following a similar trend to countries including Ireland, Iceland, Sweden and Canada.
The dip in numbers of the species – known as an ‘indictor species’ by scientists since it can be used to track the health and cleanliness of marine and freshwater ecosystems – is a sign that improvement is drastically needed to improve their environments.
Reasons for their decline are extensive, from agricultural pollution, chemical runoff from industries to roads that degrade habitats and sedimentation. Climate change, and the warming sea it brings along, are also another factor.
‘These results demonstrate the urgency with which we need to address the many pressures on freshwater ecosystems at a strategic scale,’ said Chief Executive of The Rivers Trust Mark Lloyd. ‘What we know is that salmon need access to cold, clean water and a suitable habitat to complete their lifecycle.’
‘There is a pressing need to increase dramatically the scale of work going on to remove barriers to fish migration, reduce pollution from agriculture, sewage, roads and mines, and to restore natural features and flows. These magnificent fish are in danger of becoming extinct on many of our rivers where they were once abundant, which would be a disastrous legacy to leave the next generation.’
Tackling salmon decline
Although the wider picture of salmon stock shows an overall decline, improvements on individual rivers in the UK have been reported.
Projects to tackle declining salmon levels have been completed by the Environment Agency, including building the largest fish pass in the UK near Nottingham. This allowed wild fish to reach the River Trent catchment, leading to an increased number of salmon and an improvement in water quality. Another project – ‘Unlocking the Severn’ – meant salmon could easily reach spawning grounds by improving weirs, which can otherwise block migration routes.
