Annual salmon count shows record low numbers of fish for a second consecutive year
The annual counting and tagging of juvenile wild Atlantic salmon on the River Frome in Dorset has shown a dramatic decline in numbers of fish being captured for a second year in succession, indicating a worrying downward trend which is reflected across the UK and Europe.
Since 2002, the Game & Wildlife Conservation Trust’s (GWCT) has spent four weeks in late summer catching, weighing, measuring and microchipping the juvenile salmon, known as parr, that have hatched in this 35-mile long south of England chalk stream during winter and spring.
The aim every year is to tag 10,000 salmon parr – but this summer, the Fish Research team only managed to scrape together 3,226 salmon parr. This is another record low after they only managed to find 4,593 last year.
GWCT’s Senior Research Assistant Will Beaumont is leading the fieldwork, which took place between 22 August and 17 September. He says: “Last year was the worst we’ve ever had, but this year has been catastrophic.
“This follows on from yet another year where we have seen a new record low number of adults returning from sea to spawn, confirming the continued steep decline of salmon in our rivers.”
Numbers of wild Atlantic salmon have crashed by some 80% over the past 40 years. Rivers which had tens of thousands of salmon in the 1980s now only have a few hundred in them. They are now classified as endangered in the UK and on the IUCN Red list along with other threatened species like elephants, pandas and polar bears.
In a bid try to identify what is causing the decline, and what can be done to reverse it, the GWCT’s Fisheries Research department has been studying the health and lifecycle of this iconic species since 1973 – and has been PIT tagging salmon since 2002. This means the GWCT has data going back more than 50 years, making the Frome monitoring programme one of the longest running and most comprehensive of its kind in Europe.
Working with farmers on a landscape and catchment-wide scale is key if we want to improve the health of the river and reverse the decline in salmon. This is something the GWCT has been pioneering for the past decade through farmer clusters and, more recently the Environmental Farmers Group (EFG).
Dylan Roberts, Head of Fisheries at GWCT, says: “This decline is alarming, and if it continues salmon could disappear from our UK rivers in the next 30 years. It is also sadly reflective of what’s happening in other rivers in the UK and more widely in Europe. Almost all salmon rivers in England and Wales are classified as at risk by the Government bodies.
“The issues for salmon are many and complex. They are facing much tougher conditions in the marine environment, where global warming and concerns over bycatch are posing serious threats. But if we are able to improve conditions in our rivers, and make sure they can grow fitter, larger and stronger and reproduce in greater numbers, they will stand a better chance, once they migrate to sea, of returning in larger numbers.
“My team has seen first-hand the changes to the physical nature of the river Frome. In recent years, we have seen a huge increase in the growth of algae between spring and autumn which smothers the riverbed, shades and then reduces the growth of plants like water crowfoot, which are crucial habitats for juvenile salmon and the insects upon which they feed. We’ve also seen increases in the quantity of sediment, which is mud running from the riverbanks and ploughed fields into the river where it smothers and suffocates salmon eggs.
“Excessive algae also reduces the amount of oxygen available to fish in rivers at night and especially during the warmer months, this can stress, reduce the growth of and even kill fish. The algae grows excessively due to high levels of nutrients - nitrate and phosphate which are released into rivers from sewage, septic tank discharges and running off agricultural land.
“To create a better future for salmon, we need to tackle these issues together and at scale. To date, projects have been too small and patchy - mainly due to a lack of funding and bureaucratic challenges around farming and conservation - to make the changes needed.
“There are a number of other organisations striving to do good things on rivers and we don’t want to be another group doing our own thing. We need to work collaboratively with everyone in the sector, from councils, government bodies and NGO’s like the Wildlife Trusts and the Farming and Wildlife Advisory Group.”
Ian Baggs is a dairy farmer based along the banks of the Frome near Wareham. His herd grazes the water meadows and fields near the river.
He says: “I believe farmers are custodians of the land and we have an obligation to do the right thing. It’s about securing the long-term sustainability of farming and the future of generations to come.
“For decades we used to grow maize on this field above the river, where the land slopes down towards it. We have now changed that, instead we’ve planted deep rooted grass and now graze the cows on it. This stops the problem of run off and helps improve the river, reducing the amount of silt reaching it.
“We also keep cattle moving to fresh pastures every few days, to allow the environment to recover quicker.”
“I’m happy to look at doing more, in fact I want to do more, and I’m always looking at ways of improving the health of the river, but like many I need adequate financial support and expert guidance. That’s why farmer clusters, EFG and the science based advice of the GWCT is vital.”
GWCT recognises that the UK will not meet environmental challenges such as river pollution and species recovery without this collaborative relationship with farmers, who manage 72% of the land. This is why the trust developed the Farmer Cluster concept in 2012, facilitating groups of contiguous landholders to work together to save threatened species in their local area.
In 2022 the Trust supported the launch of the farmer led cooperative Environmental Farmers Group (EFG) which acts as an umbrella group for farmer clusters and individual farms looking to access funding for habitat improvement and emissions reduction projects. It currently represents 541 farmers over an area of 341,404 hectares with groups in the South East, South West, Midlands and Yorkshire providing a blueprint mechanism for helping deliver national targets on net zero, biodiversity recovery and clean rivers.
Colin Smart, from the Environmental Farmers Group Dorset, says: “We are planning to develop a catchment conservation plan for the Frome with advice and input from GWCT fisheries. As part of that we are surveying the length of the River Frome to build a picture of where we can make improvements.
“With a sufficient blend of investment from both the private and public sector, the catchment plan has the potential to reverse the catastrophic decline of salmon in the Frome, which is an indication of the poor health of the entire river system.
“Farmers do care about the environment and can make a real difference but also need to produce food and make a living. They need adequate compensation to put the right measures in place.”
The GWCT’s salmon monitoring work forms part of a ‘Core Salmon Rivers’ research programme in partnership with the Atlantic Salmon Trust and the Missing Salmon Alliance.
Clare Scott, facilitator for The Devil and Chesel Farmer Cluster in Dorset on behalf of FWAG South West (FWAGSW), says: “As facilitators, FWAGSW ensures that farmers have access to industry expertise and best practice guidance. Working together promotes group discussion and provides opportunities to share ideas and learning.”
Salmonid electrofishing and parr tagging – how it is done
Every August/September the GWCT Fish Research Centre team set out to capture and tag 10,000 juvenile salmon and 3,000 brown trout.
Fisheries scientists, volunteers and students make up two teams of six or seven and head out daily for four weeks to cover most of the River Frome, fishing sections at a time. The tagging work is undertaken in a mobile riverbank laboratory.
At least three people get in the river and walk upstream in waders with a metal loop (called an anode) which is moved through the water to create a slight electric current in the water to slow the fish’s movement to be able to capture them.
The fish are then put in a bucket and handed over to the lab team on the riverbank to be weighed, measured, anesthetised and tagged with microchips - PIT tags (passive integrated transponder) which is what a vet will use in cats and dogs. A few scales are also taken to help age and undertake genetic analysis on the fish.
After recovering in a bucket of oxygenated water the fish are returned unharmed to the same 100m section of the river from where they were caught.