Paul Hobson investigates the rewilding of one of Derbyshire’s most stunning dales
Perfection in nature is difficult to define. Nature is just what it is and because we are human and influenced by many factors, we end up with the phrase 'beauty is in the eye of the beholder.'
We don't all see the world around us with the same eyes yet we often agree when we are confronted with fantastic scenery - and Derbyshire has more than its fair share of this. Our limestone dales can be ranked among the world's best scenery. We each have our favourite but if we simply use visitor numbers as a measure then Dovedale (over a million visitors per year) stands shoulders higher than the rest.
What is it about this dale that we find so attractive? Well, it's not hard to define. With its bubbling, clear water bisecting a varied dale of steep cliffs and ash-wooded slopes, it really is stunning. It looks natural and pristine.
However, looks can be deceptive. The problem with rivers is that we rarely look under the surface. We see clear, tinkling water, an occasional trout rising in a pool and the odd dipper perched cockily mid-stream, and think that all is well in the natural world. It is hard to dispute this, but could it be better, perhaps even more natural?
When I visited Dovedale last summer and asked some of the walkers to describe what they loved about the dale there were many common factors: the river and its clear water, the steeply wooded sides and the wildlife. A few mentioned the weirs and how they were an integral part of the river. I asked if they thought they were natural and many did think they were artificial, although no-one had any idea what their effect might be on the river and its wildlife.
There are actually 177 weirs on the Dove. It is the most 'weired' river in the Peak District. They are all man-made with one purpose - to enhance fishing opportunities when the river was stocked with a range of species such as brown trout (our native), rainbow trout (American), Loch Leven trout and fontinalis trout (brook trout from America). Fish stocking on the Dove ended five years ago and the only trout now residing in the pristine waters are brown trout.
The weirs had a job to do that is no longer required. They are now seen with new eyes by a wide range of interest groups that include Leek and District Fly Fishing Association, the Wild Trout Trust, the National Peak District Park Authority, the Environment Agency, Natural England and the Dale's owners, The National Trust.
Removing many of the weirs will have a naturalising affect on the river, taking it back a few hundred years with the idea that this will benefit the wildlife but shouldn't erode its landscape value at all.
When a weir is added to a river the water behind the weir slows down and creates a pool of almost standing water. Instead of washing down the river towards the River Trent, sediment settles on the bed of the pool and suffocates many of the invertebrates and small fish. The natural invertebrates, such as stone fly, caddis fly and mayfly that live in quick-flowing, silvery rivers like the Dove require clean, sparkling water rich in oxygen. Slower water is lower in oxygen and warms more easily, which lowers the oxygen levels even further. The sediment coating the limestone bed behind the weir clogs the gills of invertebrates and suffocates the native weeds that should be wafting gently in the moving water.
We rarely see these creatures that live under the surface and what we can't see we don't worry about.
By removing many of the weirs, but not all, the river will flow faster, creating new microhabitats with greater biodiversity. This will then create better bends, redds (trout spawning shallows) and natural pools where the larger trout can lie up and be tempted by the flies of the fishermen. The increased number of invertebrates will provide more food for the trout and other fish, such as the delightful bullhead, as well as otters, and birds such as dippers, kingfishers and grey wagtails. Even woodland birds will capitalise when the mayfly hatch in spring.
It is a win-win situation. Scenically many walkers will hardly notice the difference and the weirs that are the most attractive and have a historical and cultural heritage value will be left for future generations to enjoy.
In the modern world of nature conservation we now talk about rewilding. The Dove weir removal project is exactly that, the creation of a more natural, self-maintained, resilient river, rich in wildlife.
I spent a day last summer working with a team removing a couple of the weirs. It was back-breaking work as each large limestone boulder had to be crow-barred out individually and lifted to the side. It was also great fun as volunteers from all the organisations took part.
Interpretation is now incredibly important and I valued and enjoyed many chats with walkers as we explained the reasons behind what looked like quite destructive work. Of course, within a few weeks no one would be any the wiser that there had once been a weir there. That is part of the beauty of the work.
Hopefully, the famous 17th-century fishermen Izaak Walton and Charles Cotton who so loved fishing the Dove would approve and find that the river is now much more in keeping with their world.
If you are interested in working to help the future of this and many other projects, contact Derbyshire Wildlife Trust www.derbyshirewildlifetrust.org.uk/volunteering-opportunities and the National Trust www.nationaltrust.org.uk/lists/volunteering-in-derbyshire who both run voluntary groups across the county.
