Case Study: River Clun Recovery Project
The River Clun is a Natura 2000 site and one of only three rivers in England designated as a European Special Area of Conservation (SAC) for its freshwater pearl mussel interest. In recent decades the population has experienced a dramatic drop in numbers due to habitat loss and declines in water quality. Our project is funded for four years by WREN, Woodland Trust and Severn Rivers Trust and is working in partnership with landowners, volunteers and agencies to raise awareness of the issues contributing to decline and to fund conservation measures not available via conventional schemes. Our project has a catchment wide remit, but is also working at two sites to enhance habitat for future translocation of adult pearl mussels from parts of the catchment not likely to recover in the short-term.
What was done
The River Clun and its tributaries amount to over 280km of flowing water in a catchment area of c. 27,000 ha. Land management is varied with areas of afforestation and pasturelands in the uplands, to intensive agriculture in the lowlands. The River Clun is no longer pristine and in recent decades pearl mussel habitat has declined to such an extent that pearl mussels are now functionally extinct. There a many reasons for this, but the loss of riparian cover and suppressed regeneration of riverbanks, elevated levels of nutrients, accelerated erosion, sedimentation of river gravels, excessively high flows and extended periods of low base flows are major factors. Therefore our project is working to reconnect highly fragmented riparian habitats. In the first year of our project we have erected stock proof fencing to encourage natural regeneration of riverbanks and to reduce accelerated erosion. The project has coppiced diseased and neglected alder trees to prevent toppling and to encourage their regeneration.
Nature has been given a hand through volunteer and contract tree planting, in time this will help to re-establish the cover and riparian habitat necessary to sustain pearl mussels. Because we have excluded livestock from the river, alternative watering has been provided through a combination of solar powered pasture pumps, piped water and constructed drinking bays. Farm tracks have also been a focus of our project. Following, rainfall degraded tracks become both sources and pathways transporting sediment and nutrients to the River Clun. We have worked with farmers to upgrade problem tracks so they are no longer a conduit for agricultural runoff. Because agricultural runoff is a problem in the catchment, our project is systematically surveying and mapping the highway drainage network in the Clun catchment.
Highway drains have been identified a key conduit by which runoff is conveyed to our rivers and streams. We have identified a number of “Red Flag” sites considered to have a disproportionate impact on the River Clun, and in the course of our project (and partners’ projects) we will be putting measures to address this. Due to the scale of the issues affecting the River Clun SAC and its population of pearl mussels we can only hope to address these issues by working in partnership with other agencies. The River Clun Recovery Project integrates well with Natural England’s Countryside Stewardship Scheme (and predecessor schemes) to pick up those farms not currently benefiting from funded projects. We are also working with the Environment Agencies’ ‘Un-muddying the Waters’ Project in the Clun, which is seeking to address Water Framework Directive (WFD) related issues.
Although the project is driven by the unfavourable condition of the Clun SAC, and because the pearl mussel itself requires very high standards of habitat and water quality we are delivering for other habitats and species also. The project is working beyond the riparian corridor to benefit a range of wildlife in the Clun Catchment.
- Riparian habitat restoration/creation: 7.06ha equivalent to 6.728 linear km 2,200 riparian trees planted.
- Runoff mitigation work: Track/gateway restoration and culvert improvement works = 118m or 0.036ha
- Invasive species control: Volunteer Himalayan balsam management on the River Kemp: = 0.156ha
- Our volunteer effort has been significant, amounting to over 900 hours of volunteer effort. Working with the Severn Trees Trust, Shropshire Wild Team, Farmers, and environmental professionals we have been able to plant new riparian woodlands, tackle Himalayan balsam outbreaks, construct tracks and watercourse crossings and survey 1/3rd of highway drainage network in the Clun catchment.
- This year, we have liaised with 23 Farms, and capital works have been agreed for 18, with works commenced or completed at 11 sites.
The issues affecting the decline of the pearl mussel in the River Clun are complex to understand and challenging to address. We have only been able to achieve what we have done to date due years of investment from Project Officers working in the Clun Catchment and by building on the goodwill generated by previous project work in the Catchment (which includes HLF funded Blue Remembered Hills Project and the SITA funded Clun Pearl Mussel project). This effort has been recognised by the farming community who work closely with our project to put in significant levels of in-kind support. We are also supported by our project partners through the Clun Pearl Mussel Steering Group which works at a policy and strategy level to guide our work. As the Clun is the focus of much on the ground activity we also have the Clun Field Officers Group, which allows us to coordinate our activities and share best practice.
Shropshire AONB Partnership
- Project Web pages: http://www.shropshirehillsaonb.co.uk/aonb-partnership/rivers/
- River Clun Nutrient Management Plan: https://www.gov.uk/government/publications/nutrient-management-plan-river-clun
- Protected freshwater pearl mussel sites in the UK: http://jncc.defra.gov.uk/protectedsites/sacselection/species.asp?FeatureIntCode=S1029
Quote from project manager:
“Working in the Clun is challenging and having completed year one of the project I feel we have delivered a big “tick in the box”. Getting off on the right foot is important and have no doubt we are on track to deliver a successful project”. – Mike Kelly, Natural Environment Officer
Key search words: River Clun SAC, WFD, Freshwater Pearl Mussel, Riparian, Pathways, Nutrient, Sediment, Partnership, WREN, Habitat Restoration
Photo Credits: New Riparian Woodland on the River Clun, River Clun Recovery Project, Abcott Manor – Shropshire Hills AONB