Freshwater pearl mussels are extraordinary creatures that can live for over 100 years. They help keep rivers clean by filtering up to 50 litres of water a day, but sadly, they’re now critically endangered in Europe. In the Dee catchment, only a tiny population remains. No young mussels have been seen for years, due to poor water quality and loss of habitat.

This fragile population, one of the last remaining in Wales, is too small to recover on its own and requires captive rearing and release to help it survive in future. We’ve taken adult mussels to a special hatchery where they can breed safely, until they are ready to be released back into the river.

In preparation for when the young mussels return, we’ve restored a 300 metre section of the River Alwen at Llanfihangel Glyn Myfyr by creating a habitat rich in gravels, boulders and woody material to help them grow and thrive. They need clean, fast flowing water with a stable riverbed and plenty of structure such as stones and logs, which will provide pockets of protected habitat to shelter from high flows.

Working closely with the landowner, large woody material was fixed in the channel and 60 tonnes of gravel was placed at the upper end of the site ready for the winter flows to distribute it naturally downstream. In addition to the material placed in the channel, the whole section was fenced out with heavy duty panel fencing to prevent access to the river as its adjacent to a picnic and play area. The site is now ready for the reintroduction of freshwater pearl mussels in late spring or early summer this year.

By restoring these natural features, we’re giving the freshwater pearl mussel a fighting chance. This work doesn’t just help one species, it benefits the whole river ecosystem, making it healthier and more resilient for generations to come. You can listen to our Project Officers explaining the fascinating lifecycle of the pearl mussel here.

With many thanks to Llanfihangel Glyn Myfyr Community Council for their cooperation in delivering this project.

We have exciting news from the Afon Tryweryn! For the fourth year running, salmon have been seen spawning on the gravel that we’ve been regularly introducing in this section of the river as part of the project. You may remember us mentioning in our last newsletter that in the autumn we were introducing several hundred tonnes of gravel here, which is vital for fish spawning as it provides a clean, well-oxygenated environment to bury eggs and creates sheltered habitat for fry to develop safely. We’re delighted to see that these efforts are making a difference, and that salmon are indeed spawning in these areas.

This winter is the first time we’ve managed to capture drone footage of fish spawning here, but we didn’t want to get too close to avoid disturbing them so it may be tricky to spot clearly in the video. The light patches of gravel on the riverbed are the redds - the areas which have been disturbed by a hen (female) salmon as she creates a depression in the riverbed into which she will lay potentially several thousand eggs.

This is great news for the project, and shows how important it is to have the continuous introduction of gravel below a reservoir to ensure good quality spawning habitat.

Riverside corridors are very effective at excluding stock from poaching the banks and reducing sediment and nutrients from entering the Dee. The corridors act as buffer strips that protect the river as well as encouraging the riverside ecosystems to flourish.

This winter, a total of 2.6 kilometres of riverside corridor has been created in the upper catchment. This includes 1,000 metres of fencing extending from our previous work on the Afon Mynach, and the installation of a solar pump water system which will exclude all livestock from this section of river.

In addition to the Mynach work, a small un-named tributary which enters the Afon Tryweryn some 100 metres below the Mynach confluence has been completely fenced off. The landowner here will provide an alternative water supply to livestock in the surrounding fields. This type of small tributary is very important to the catchment as trout and sea trout use these areas to spawn. Fish up to 3lb have been seen spawning in this stream in the past!

The last section of fencing in the upper Dee this winter is a 500 metre stretch on the main river at Ty Isaf. This riverside corridor is a continuation of previous fencing we’ve completed here with other landowners, and we’re pleased to say that this now means the whole area upstream of Bodweni has been fenced all the way to Bala. This recent scheme also includes a solar powered watering system, and will exclude dairy cattle from entering the watercourse.

With thanks to all the landowners we’ve worked with in this area to achieve such an extensive length of continuous fencing in the upper catchment.

Having worked on the LIFE Dee River project as Land Management Officers for four years, we asked Tom and Ifor to summarise some of their highlights during the project and share a snapshot of their day to day roles, from farm yard improvements to culvert upgrades, and installing forestry crossings to creating natural bank stabilisation.

“Working as a Land Management Officer on the LIFE Dee River project gave me the chance to spend a lot of time out on the ground, working directly with farmers, foresters, and partner organisations across the Dee catchment. The role was varied and practical, combining site visits, problem-solving, and organising delivery, all with the shared aim of improving water quality and supporting more sustainable land management.

“Much of my time was spent identifying where small, targeted changes could make a real difference - whether that was improving farm infrastructure, reducing run-off into rivers, or upgrading forestry tracks to better manage water during heavy rainfall. It was a role that required flexibility, good communication, and an understanding of how environmental goals fit into day-to-day land management…”.