Several months have passed since Nethrton burn on the Doon was polluted with slurry when a valve and back up safety valve broke on a tank near the burn. This burn has long been a concern of ours as its been under producing for at least 10 years that we know of .We’ve identified livestock access issues and asked SEPA to investigate problems on several occasions. The image below illustrates the problems we found in 2012/13 that were reported yet when SEPA attended, they couldn’t find any issues.
A report by the Doon’s head bailiff in 1859 (or thereabouts) named this as one of the most important spawning tributaries in the catchment. When comparing that statement to today’s performance and condition, the burn is unrecognisable to what it must have been back then. The Doon lacks spawning tributaries, particularly in the lower and middle river so those that do exist should be important and maintained in a useable condition.
This year, the slurry release occurred and SEPA were again in attendance. After ecologists inspected and then later revisited the burn, we have been informed that the burn has recovered. There were no fish killed by the incident apparently. The landowner has been cautioned, instructed to have his tanks inspected by a qualified engineer and SEPA will send a further team of specialists to look at agricultural practices that may impact the watercourse or water quality. We await any information on that but thought we should undertake a fish assessment this season to see how the current fish stocks are performing.
A couple of weeks ago, we surveyed upstream of the farm (and slurry pollution) and found the burn to be severely impacted by livestock which has led to large areas of the burn being affected by silt and fine sediment. Water quality issues exist as a result. There were no salmon in the upper reaches but a low density of trout that gives some hope that improvement can be achieved with appropriate changes to land use. We are not against livestock or dairy farming but they must be done sensitively and with respect for the wider environment and in particular the watercourses that can easily be destroyed through unfetter livestock access. The habitat throughout the burn has great potential but needs considerable effort if salmon and trout are to spawn successfully and reach their full potential.
We found a small weir (in poor condition) that may prevent salmon migrating to the upper reaches and will seek to remove this next year with assistance from the Board and permission from SEPA. In reality, I’ve no doubt this stops all salmon migrating upstream but we haven’t performed a Sniffer Barrier assessment on it and therefore can’t say so with any certainty but that is my opinion. This should be addressed asap.
Yesterday we managed to survey the lower burn in an area that was affected by the slurry release. Surprisingly we did find a very small number of juvenile salmon and trout. However, in the area surveyed, there were clear indications that the burn has and still suffers from long term and severe siltation arising from livestock grazing pressures. Since the pollution incident, livestock appear to have been excluded from water margins effectively and the adjacent land in the lower reaches is well vegetated for the first time in years however there are still signs that livestock poaching has been an issue if one cares to look. Just walking the ground reveals the poaching by cattle hooves and anyone experienced in surveying should be able to identify this. Currently, despite the stock exclusion, the bed of the burn remains heavily silted and spawning substrates are in poor condition. We have to hope there is no return to the old practices of over winter grazing through the wooodland and water margins.
The situation should improve with continued livestock exclusion from the lower burn however it will also require the same in the upper reaches too otherwise fine sediment inputs will drift downstream impacting the whole burn. Interestingly and worryingly, the Board through the Trust previously offered assistance with fencing that was rejected on several occasions. We will suggest a meeting between the Board and Landowner to discuss how this burn can be improved. ART believe the DSFB has every right to expect the landowner addresses these issues either with their support or not. We can only hope that SEPA agree and use their leverage as the Regulator to ensure this happens. The Diffuse Pollution Initiative appears to be failing as these type of livestock issues are not uncommon across Ayrshire and we would have hope that they were a thing of the past by now.
After surveying the burn yesterday, we took the opportunity to remove a blockage in the lower reaches that threatened to prevent migratory species passing. This does require further effort with a chainsaw and pinch bars. We didn’t have tools with us yesterday or it would have been done but hand work cleared a route through. We will attend to this asap.