Glen Prozen river restoration will help to boost fish numbers

The Esk Rivers & Fisheries Trust (ERFT) carried out the research of behalf of Forestry and Land Scotland (FLS).

In order to set a baseline against which to measure success, FLS commissioned EFRT to determine the current state of juvenile freshwater fish and invertebrate populations - their food source.

There were few barriers to fish movement and while in-stream habitat and water quality was found to generally good, low fish numbers were thought to reflect a lack of nutrients and invertebrates.

FLS Environment Forester Gareth Ventress said: “This highlights and reinforces the importance and value of our river and burn restoration work in Glen Prosen.

"It will provide environmental benefits for fish in Glen Prosen and, by supporting larger populations of juvenile fish, potentially the wider River South Esk catchment.

“The baseline data will serve as a benchmark for comparing fish and invertebrate populations against future results following changes to how the land across Glen Prosen is managed.

“We recently completed putting up almost 14km of fencing to exclude deer and rabbits from sections of the riverbank to protect young broadleaved trees, supported by the Nature Restoration Fund (NRF).

"The NFR funding will also support extensive planting of over 14,000 native trees along the river and tributaries along the glen next year.”

Dr Craig MacIntyre from the Esk Rivers & Fisheries Trust, said that the work being carried out on the Prosen Water could be crucial in helping to boost fish numbers, with a knock-on effect throughout the river’s catchment area.

He said: “The Prosen Water is an important tributary of the River South Esk in Angus – classified as a Special Area of Conservation for Atlantic salmon.

“With a decrease in Atlantic salmon numbers in the River South Esk over the years, land management measures that improve fish habitat in Glen Prosen could play a key role in protecting and improving the wild salmon and sea trout populations further down river and across the catchment.

“It is good to see FLS already adopting and working on our recommendations and we look forward to seeing the results in future.”

Planting or regenerating riparian broadleaved trees to provide additional shade and lower water temperature was also recommended, to further improve the chances of successful breeding.

The fallen leaves will also provide nutrients to support mayfly larvae and other water invertebrates – the main food source of the juvenile Atlantic salmon and trout.

The Scottish Government’s Nature Restoration Fund is managed by national agency NatureScot as part of the £1,401,907 grant for the ‘Restoring the River South Esk: An nature-rich and climate resilient catchment’ project, which was awarded in 2024.

Forestry and Land Scotland (FLS) manages forests and land owned by Scottish Ministers to support and enable economically sustainable forestry; conserve and enhance the environment; deliver benefits for people and nature and support Scottish Ministers in their stewardship of Scotland's national forests and land.