After some surveying on the mainstem with Duncan Ferguson I was taken on a conducted tour of habitat works underway on the Dulnain and Achnahannet Burn. Starting in the Dulnain we had a look at a large field with an unfenced river frontage extending to 1400m. It is regularly used for overwintering cattle and the banks have suffered as a result.
Cattle need to drink a lot each day and the damage to fragile riverbanks by these heavy animals results in a lot of silt entering the river.
Further downstream the damage to the bank structure was obvious with riverbank alder trees undermined and roots exposed.
The solution for this sort of damage is stock proof fencing and it was pleasing to hear that the entire riverbank will be fenced in an extension to the Achnahannet Burn works. The fencing on the burn itself is progressing very well. The fence is of high quality and a generous buffer strip implemented.
A short distance downstream an over widened bend in the burn would be a good site for monitoring changes to the burn following fencing.
Below the road the fencing is complete.
The habitat within the fenced areas should improve with more bankside cover and reduced silt input. However the impacts of damaged habitat can extend well downstream with silt and cattle manure causing enrichment and smothering spawning gravels and sensitive species such as stoneflies and freshwater pearl mussels. In total over 6.2km of fencing is going to be erected under this project. A nice contribution to improved habitat both within the Dulnain and beyond.
It was clear that there was a high proportion of silt and sand in bed of the burn. The input if such material should decline after fencing. Consequently this looks like an area where some practical habitat works to loosen the gravel in preparation for spawning may be worthwhile. This sort of activity is normally done in late summer so if anyone is interested in assisting with gravel cleaning please let me know.