- Pearls in Peril
- PiP Projects
A simple technique to improve the quality of the river habitat for mussels and other species is stock exclusion fencing.
- Stock accessing the river for water can churn up the riverbanks (stock poaching). This can result in mud and silt to entering the river and ‘clogging’ up the riverbed. Clean riverbed substrate is particularly essential for juvenile freshwater mussels who live in the riverbed for the first few years of their lives. If there is too much silt lying on the riverbed there will be little, if any, oxygen available which means the mussels will be smothered.
- The stock poaching also de-stabilises banks causing more silt to enter the river and loss of land for the landowner.
- Compacted ground is another issue which can potentially increasing ‘run-off’ of excess soil and nutrients into the river.
- Stock can also directly damage mussels and churn up the riverbed by trampling.
Benefits of fencing
- Stock exclusion fencing is beneficial to both the river and the landowner.
- Creating a fenced buffer strip protects stock from being washed down the river or damaging themselves in the river.
- It stabilises the bank by allowing trees and vegetation to grow reducing the loss of land and the silt input to the river.
- Compaction is reduced by allowing water to more easily infiltrate the ground during spates and heavy rainfall as well as providing a buffer from the polluting impacts of potential ‘run-off’ from the fields.
- Buffer strips provide added benefits for biodiversity by providing food and shelter for many animals. Vegetated riverbanks also provide shade to the river keeping it cool which is essential for mussels and fish.
Fencing and Pearls in Peril
Landowners have been very supportive of stock fencing and the Pearls in Peril Project has fenced approx. 6 km of the main river and tributaries with generous buffer strips (5-15m). These buffer strips have all been planted with native trees. Alternative stock watering, such as water troughs has also been provided where necessary.
The River Ehen is a typical upland river prone to spates and flooding and as such line wire fencing was used rather than standard stock fencing. Using line wire fencing allows for debris to go through the wires rather than getting caught on stock fencing and weakening/breaking the fence. In addition, strainers were installed every 50m to ensure if the fence did break during a spate that only short sections would need to be repaired. This type of fencing has proven very successful in this catchment and has also been adopted by landowners in Scotland with some fantastic feedback from them. We used the specification drawn up by Natural England for riverside fencing. See attached document.
See some before and after photos below…