Freshwater pearl mussel project

This project is funded by Eryri Nature Partnerships in partnership with Parc Cenedlaethol Eryri and Welsh Government.

Learn more about freshwater pearl mussels and why they are so unique.

Freshwater pearl mussels in the afon eden

the project goals.

  1. Improve fish and pearl mussel habitats by adding spawning materials, completing the riparian buffer zone, and protecting riverbank biodiversity.

  2. Partner with local groups and schools to raise awareness about Afon Eden's SAC/SSSI species through training on river surveys, biosecurity, pearl mussels, and otter holt building.

  3. Improve access by replacing stiles with footpath access and gates to enhance public access while protecting the environment.

  4. Educate the general public with guided walks and install information panels to highlight the conservation efforts and key species benefiting from the project.

The Afon Eden, a Special Area of Conservation and Site of Special Scientific Interest, is home to one of the UK’s most endangered species, the freshwater pearl mussel (Margaritifera margaritifera). These mussels, are crucial for maintaining river health, filtering water and supporting biodiversity. However, their populations have dramatically declined due to habitat loss, pollution, and changes in river flow. The mussels’ survival is tightly linked to salmon and trout populations, another declining species. Work is taking place to restore habitat and create a thriving Afon Eden.

protecting our endangered species

Over the years the Afon Eden has faced several issues that threaten its ecological health and the habitat of the freshwater pearl mussel.

  1. Habitat and Spawning Ground Loss: There is a shortage of suitable habitats and clean, gravel-rich spawning grounds for species like salmon, otters, and freshwater pearl mussels. Land use changes and environmental degradation further reduce these critical areas, hindering wildlife reproduction and survival.

  2. Climate Change: The river is increasingly impacted by droughts and flooding, which disrupt natural flows and degrade habitats, affecting species that rely on stable river conditions.

  3. Livestock Issues: Livestock accessing the river causes poaching and water quality issues, leading to erosion and nutrient pollution.

  4. Sewage Pollution: Untreated or poorly treated sewage entering the river contributes to nutrient enrichment, degrading water quality and further harming sensitive species and habitats.

  5. Invasive Species: Invasive plants like pondweed outcompete native species, disrupting the river's ecological balance and affecting biodiversity.

  6. Sedimentation: High sediment runoff from agricultural ditches and erosion reduces water quality and smothers vital habitats.

  7. Riparian Buffer Zones: The absence of riparian buffer zones allowed pollutants, including sewage and agricultural runoff, to enter the river more easily, exacerbating water quality issues and habitat loss.

issues facing freshwater pearl mussels

community

The success of our freshwater pearl mussel conservation efforts depends on the active involvement of the community. Local residents, educators, and students play a vital role in monitoring, restoring habitats, and gathering data for the project. By participating, the community not only helps protect this endangered species and its ecosystem but also takes ownership of sustainable solutions to safeguard the health of their local river. Through collaboration, we can ensure the survival of the freshwater pearl mussel and the biodiversity it supports.

Volunteers conducting a sweep net survey on the Afon Eden
Volunteers on planting trees on the afon eden
Ysgol Bro Hedd Wyn pupils on a site visit
Volunteers surveying for deep peat

education


As part of this project the North Wales Rivers Trust have been working closely with local schools to provide educational workshops and site visits to learn about the critically endangered freshwater pearl mussel and the importance of protecting our freshwater ecosystems.

We have been actively working with the local school to educate students about the life cycle of the freshwater pearl mussel through the creation of a storybook. This engaging project enhances their understanding of this endangered species while fostering a deeper connection to their local environment and encourages creative thinking.

In addition to the storybook, we offer the opportunity for pupils to attend site visits where they can participate in activities like bug house building and invertebrate sampling.

Through these initiatives, we aim to empower the next generation to take an active role in safeguarding their local waterways and the biodiversity they support.

“This project has been invaluable for enhancing local ecosystems and biodiversity. By improving habitats along the Afon Eden, we’ve not only helped the freshwater pearl mussels but also fostered healthier conditions for all riverine species.”

— Dr Liam Whitmore , Lead River Habitat Officer

work so far…

phase one

reintroducing gravels and boulders

To improve the riverbed's natural structure, we have reintroduced over 60 boulders and added 100 tonnes of river-washed gravels. These actions are designed to create viable spawning habitats for local fish species, supporting the overall health of the ecosystem.

Livestock management

We have implemented fencing measures to exclude cattle and sheep from a 2.5-kilometer stretch of the riverbank. Additionally, we have installed solar-powered pumps, hardstanding areas, and troughs, providing alternative drinking sources for livestock and further protecting the river from potential contamination.

Riparian buffer zone

We have established a 10-meter wide riparian corridor that is already enhancing habitat diversity. This initiative includes the planting of over 1,000 native trees along the corridor, which will play a crucial role in stabilising riverbanks, improving biodiversity, and providing essential shade for the Afon Eden as temperatures rise.

Working with ysgol bro hedd wyn

We have collaborated with students to create an educational storybook that explains the life cycle of the freshwater pearl mussel. Additionally, we conducted site visits where pupils built bug houses and participated in an invertebrate survey, enhancing their hands-on learning experience.

Phase 2

Tree planting

Our tree planting initiative, which includes the pollarding of established willow trees, is set to create bank stabilisation and improve wet woodland habitat. These trees will provide nutrients for invertebrates and cover for fish, contributing to a balanced ecosystem in the face of climate change.

Community monitoring

Extensive surveying of the site has been conducted including both aquatic and terrestrial invertebrates, habitat, peat and monthly water quality testing.

Establishing a wildlife walk

We are working to establish a wildlife walk, designed to allow visitors to explore this beautiful site and appreciate the increasing biodiversity. This scenic trail offers an opportunity to witness firsthand the restoration efforts that are revitalizing the ecosystem and fostering a thriving environment for wildlife.

Check back soon for more updates!