Wild Salmon

Lord Pearson of Rannoch Excerpts

Tuesday 14th May 2019 Grand Committee

[Lord Pearson of Rannoch (UKIP)]

My Lords, I have listened to the debate so far, upon which I congratulate the noble Earl of Shrewsbury. However, I have not heard mentioned what I feel may be another cause of the salmon’s decline in Scotland.

Before the clearances some 200 years ago, the highland economy depended largely on cattle, with very few sheep and deer but an abundance of fish and other wildlife by today’s standards. Sheep replaced the cattle and did very well on the rich ground they left behind. Deer started to increase because the men were no longer there to kill them. Most of the highland catchment areas were gradually taken over by sheep and deer, which prefer the short, nutritious grasses, while cattle eat the longer grass, particularly purple moor-grass—molinia caerulea—which otherwise grows tall and shuts out the light, forming an unhealthy mat when it dies back each autumn. It lives naturally in wettish ground but gradually colonises drier ground, which should carry heather, berries and many other plants, if it is allowed to. It grows quickly and establishes itself in a couple of years after large-scale muirburn, smothering much of what was there before. Cattle then turn it into rich manure—much richer than the droppings of sheep and deer—letting in the light for the benefit of other plants and breaking up the unhealthy molinia mat with their hooves. Earthworms and other insects do well under cowpats, even on acid soil such as ours, whereas they can hardly live under the meagre droppings of sheep and deer.

Some years ago, we ran an experiment, putting cattle back into the catchment area of an old spawning stream. The molinia reduced from 52% cover in 1993 to 13% cover by 2005. The effect on the water quality was less obvious, but there were signs of improvement by the time the experiment ceased in 2009. We are now planning to start another, much longer one, perhaps for 25 years, looking particularly for any increase in the food available for alevins when they finish their yolk.

I should add that our experiments take place in the head waters of the Tay, on Rannoch Moor, which consists of deep peat sitting on granite. Only 60 years ago there were still quite a few salmon; they are now almost extinct. I suppose that spawning streams that run off richer mineral-based rock may not have been so affected by the absence of cattle in their catchment areas, but by the other factors that noble Lords are mentioning. We gave a major conference on our first experiment in 2008. I would be happy to send the Minister the resulting brochure, in case anyone in his department is interested in looking into whether this could be yet another factor in the decline of such a noble fish.