PINPOINT

Just leaving Cornwall after a week learning how to identify and tackle diffuse pollution of rivers using the PINPOINT method. Its the end of October and the weather has been impresive, hitting 18 to 20 degrees most days. Three of my fellow students spent their mornings swimming off the North coast. It wasn't for me, as much for the 5am starts as anything.

The course was run by the West Country Rivers Trust and the Association of Rivers Trusts. We were given a great insight into the work the West Country Rivers Trust have carried out down in Cornwall and Devon on finding win-win situations with landowners and farmers to reduce inputs of sediments and nutrients to rivers. This improves in-stream habitats and increases Salmon and Trout numbers. It also creates a deeper understanding between farming and conservation creating less polarised views.

It was good to see a variety of farms from high intensity dairy operations to low input extensive organic smallholdings. The contrast between the two was fascinating. We saw how dairy operations can concentrate nutrients over a small area of land whilst more extensive systems gave us a view into a nearly lost pastoral English landscape that provides a true habitat mosaic. What was even more intriguing was the mix of options between the two systems that helped tackle diffuse pollution. Simple measures such as fencing river banks, putting hard coverings around supplementary feeders, sub-soiling to reduce soil compaction and coppicing multi-stem river bank trees to reduce shading and increase ground cover all enhance riparian habitats and break the links between erosion sources and watercourses.

Its now the turn of myself and my fellow students and rivers trusts colleagues to roll out similar schemes around the country. Its only by working with agricultural communities that we will find ways to reduce diffuse pollution without impacting on farm incomes. Many of the options available will even save time and money.

Redmire falls

Its been a gusty start to the weekend with long spells of swirling rain interspersed with the brightest of autumn sun. The beech and ash trees are vivid yellows and deep coppers. You can follow the track of the wind as it passes and moves down the river bank by the falling leaves. In the strongest gusts it feels as though someone has picked up this pocket of the world and given it a good shaking. One moment the air is empty the next tumbling, spinning, leaves fill it up. The copper leaves twist and turn catching the sun so that they flash like polished bronze.

The river is slowly rising. Ive tried to cross it four times and each time its overtopped my wellies. I get halfway, even further, but am forced to turn back all four times. I got to the tight cataract of water where the river Ure is forced by an upward tilting ledge of limestone down into a bottleneck. This is where the fish will navigate upstream. Here I'm nearly at the far bank and can see that the beech trees are tapped directly into massive beds of grey limestone. Its hard to believe but their roots will force these rocks open, prise them apart so that they tumble into the river. It wont happen here for sometime I think but it will happen.

I have sat and waited here on numerous occasions but still not seen a fish jumping. Today this doesn't bother me because I'm fascinated by the movement of the leaves in the water as they get caught in the current or in eddies. The water by my feet is moving fast and right next to my foot a scour hole holds masses of leaves, they spin in tight circles caught by a twisting current. Its easy to see how pebbles caught in the same place would scrape out a circular pit. In other places leaves are caught against rocks or tangled in mosses. Below the ledge the deep pool is smothered in them. They are massing in rafts in the slower waters of the surface and underneath they move faster caught in the quickest part of the river. It looks like they are sliding beneath the surface leaves.

I sit and wait for an hour or so but nothing happens so I return to the bank and then wade through the shallow edges of the river watching a dipper drop from rocks into the water. It appears to be whirring round, its back causing a rise in the surface so that I can follow its tracks. Everything is spinning and twisting today.

There is a little stream that joins the river on the north bank. I follow it upstream and watch two more dippers, their wings blur as they fly rapidly upstream. Some of the gravel seems to be newly turned and I suspect Ive found a redd. It seems the perfect place, just enough current to replenish the oxygen levels, the gravel is the right size and this spot would only dry out in the deepest, hottest of droughts. I walk round it not wanting to compress the gravel. I think I'll see if I can electro-fish here next spring to see if I'm right.

The rivers are quiet.

I keep getting reports of fish movement upstream but I haven’t had the luck to spot anything yet. Since the records came in the rivers have dropped again. Even though there’s been a day of rain it has only just made the dizzy heights of light drizzle and the river is stubbornly refusing to respond. I went down to Aysgarth Falls late afternoon on Sunday but the water was so low nothing would have made the attempt. A heron and a few mallard ducks sat above the upper falls and that was about all. The electro-fishing kit is in store for the year and my sampling nets are only going to get another day or so. Things in the rivers seem quiet and there is just the spawning to come and then it will be a matter of waiting for spring before I can start serious river surveys again.

Plenty to do in the meantime so boredom won’t be a factor. Down to Cornwall next week to learn about a farm survey method called PINPOINT that the river trusts and Natural England have organised. This aims to help identify where the sources of diffuse pollution on a farm are. It should help farmers meet the requirements of the Water Framework Directive, may even save some money. Then there are lots of farm surveys to carry out before I take three weeks leave. The plan is to lock myself away on Islay and get on with writing up the project I’ve been working on for the past three years. I’m hoping it will be miserable forcing me to sit in and get on with it...it would be just my luck for unseasonal sun!

Change and restoration

Upland rivers are fascinating places that possess a raw quality. Full of rapid change, violent spates to low flows in quick time, they pose challenges to people and nature. It is this rapidity of change that keeps them alive, keeps people drawn to them and puts their ecosystems on a knife edge of existence. One severe flood, drought, landslip or pollution event can alter their ecology for years. And when a natural system flips between threshold states dragging it back to its original condition is complex and challenging, beset with frustrating feedbacks and full of unexpected consequences. The new science of restoration ecology has discovered this time and again. What has appeared to be an obvious intervention can force a natural system to skew off towards some other state not accounted for during intervention planning. This has resulted in more measured approaches to reverse interference and has revealed that ecology does not exist in easily flipped parallel states but occurs in complex dimensions of interacting multivariate factors that we can never fully understand.

But not fully understanding something does not mean that we cannot understand it enough. Beneath the aesthetics of these places lie scale upon scale of interacting processes within and between both the living and non-living components of a system that create forever fluctuating conditions. However, even though they fluctuate, under prevailing conditions they are always pulled back towards some unknown average. In order to understand enough we need to simplify these interactions down to basic assumptions that explain them in as much detail that is required in order to predict the outcome of an intervention. This is not a magical process and can only come from experimentation both in laboratories and natural systems. And we are beginning to understand enough though it would be arrogant to suggest that we will never make mistakes during restoration efforts, but with restoration ecology it is the mistakes that guide learning.

The biggest experiment (and probably mistake) we are undertaking is one we have not planned but has come as a consequence of modern economies and lifestyles. An article published in 2007 in Global Change Biology by Durance and Ormerord showed that upland stream macro-invertebrate assemblages may decline by 21% for every degree centigrade rise in water temperature. This is of concern to freshwater ecologists as after primary production these are the most important components of upland river systems. What we have learned in recent years is that such a change would be difficult to reverse and as future temperatures are forecast to increase for sometime it may be that these upland river systems are destined to become shadows of their present selves.

The intricacies of the dales

The little intricate waterfalls of the dales are the hidden gems of this land. Everyone knows the big famous ones like Aysgarth and Hardraw (both of which have had visits by Kevin Costner) but tucked away on some of the small high altitude streams are jewels of waterfalls that are rarely visited. Some of these are virtually dry but surge into life once the clouds burst. These ephemeral places contain ecology trained by evolution to cope with constant change.

Walks over the hills brings a natural closeness with the land. You can become lost in the scales here. One moment watching pipits swarm across coarse grass swards to pick at tiny beetles the next taking in wide vistas or your vision being tunnelled down a far winding dale. Hills like Ingleborough and Pen-y-ghent always seem to break into the skyline. Their obvious stepped tops revealing millions of years of strata, borne from scales we can barely grasp.

Heading over the top from Ballowfields the sound of water rushing beneath scree piles highlights that you are walking over limestone. The rock is taken into solution by acidic rain and streams drop underground forming caves and caverns from the tiniest of sink holes that swallow water with a giants thirst.

The water here doesnt behave as expected. Below the summit of Addleborough, a brooding hill that decieves its low altitude, is a waterfall dry for most of the year. Water is swallowed from the stream above and as you walk over the land you can hear it bubbling and gurgling beneath the surface like a hungry stomach. And at the lower reaches of the redundant waterfall it re-emerges from two places before combining back into one of the best trout spawning streams of Wensleydale.

And if you walk the other way, towards Addleborough top, calcareous flushes clear and potable emerge from the ground. Just metres from their source they mix with dark peaty streams and then for a short distance two different waters flow side by side till they become mixed, their pH and chemistry settling somewhere between the two.

In many ways water has shaped this land. Over 300 million years ago coral reefs grew in tropical waters and their remnants now form the majority of rock in the dales. Then huge columns of frozen water scraped the land forming u-shaped valleys that are the prominent feature of the landscape. After this liquid water ran over the surface of these scraped clean valleys cutting narrow V's in the land and dissolving the rock to form the caves and caverns that form underground mosaics like fungal hyphae. This isn't a perfect timeline of the processes but the idea of how these places were formed is there.


In the last few thousand years people cultivated the land and our signals can be seen all over the floodplains and down to the Humber estuary. A soil core of these plains shows that the rate of sediment movement increased massively after we cleared the original vegetation. It shows that we can have bigger impacts on the land then we suppose. But it is this patchwork of fields delineated by dry stone walls created by farming that is one of the biggest draws to the dales, and rightly so.

Modelling at the catchment scale

Understanding how water moves across the land and what chemicals and sediments it delivers to rivers is vital to the understanding of river ecology. The rivers trust movement has played a key role in recent years by helping to decipher how catchment processes control river morphology and how morphology and water quality affect ecology.

Excessive fine sediment in upland rivers degrades river habitats by clogging up the spaces between the gravel. This reduces egg survival of Salmon and Trout and changes the macroinvertebrate communities by favouring organisms such as Chironimidae worms over Stonefly and Mayfly.

A number of rivers trusts including the Yorkshire Dales Rivers Trust have been using a modelling tool developed by Durham and Lancaster universities called SCIMAP (Sensitive Catchment Integrated Modelling and Analysis Platform). This provides detail on where fine sediment is likely to be delivered to a watercourse based on slope, landcover and its associated erosion risk and rainfall.

SCIMAP outputs show the average risk for in-stream fine sediment in any catchment being modelled with a number of risk classes either side of the average ranging from high risk (red) to low risk (green). Underneath this output is a second output in grey that highlights the land parcels of a catchment most likely to be the source of the sediment. From this it is easy to locate the red 'streams' and then look up stream for the most likely locations that are delivering the sediment. Some ground truthing is then necessary but once the risk has been established it is possible to enter negotiations for changing land management to methods that can reduce these inputs. Simple measures such as buffer strips or contour planting of trees slows surface run off allowing sediment to settle out before the water reaches a watercourse.

This has the benefit of reducing the degradation of rivers and streams and allows species composition to restore itself back to the natural community of the river type. It is these simple habitat measures, developed through catchment scale thinking, that will restore habitats to something like their potential. This kind of large scale thinking is constantly developing which makes working as part of a rivers trust an exciting and rewarding vocation.

Raydale and Semer Water catchment project

Work in Raydale has been going well with Deborah Millward leading a fantastic catchment project. This small valley has it all, forestry, dairy, beef, sheep, moors, nature reserves, one of only two glacial lakes in Yorkshire, a good number of gills and streams and one of Englands shortest rivers, the Bain. The dale has an active farming community that contain knowledge stemming from generations of land management.

As with all land in the UK there are pressures and conflicts for space which has resulted in a number of issues that the Raydale project has been trying to address. First there is the threat of a changing climate that seems to be resulting in heavier downpours and rapid flows of water. This is compounded by artificially drained moors which allow water to flush through the catchment with greater speed then would naturally occur. Fleet moss, one of the moors at the head of the dale, is severely eroded and hagged and has delivered tonnes of sediment to the river network resulting in habitat degradation for fish and riverflies. Moving downstream it appears that gills and stream banks are eroding with stock access to rivers exacerbating this in a few places.

With leadership from Deborah and the local community a good number of actions have taken place that will help reduce land management risk to rivers. This has included fencing off river banks, planting gills with native trees and restoring a gravel bed stream that has been running over a historic right of way back to its natural course. Further action will include the devlopment of a small hydro-electric scheme which may provide a future income for Raydale and help them establish their own charity to support the community and land managers in future years.

Over the next few years it is expected that the open drains on the moors will be blocked and heather restoration will be carried out. Lower down the dale catchment sensitive farming methods are being championed to ensure that farmers can achieve an income whilst also preserving the beauty and ecology of the dale and its streams.

October rain

After a September with little rainfall October 6th finally brought a decent spell of wet. The rivers responded rapidly swelling up and turing peaty auburn for the first time in weeks. By the time it cleared the Wharfe and Ure where racing and gathering pace. After a dry night they began to drop back and it seemed a good time to look for fish jumping. I headed down to Redmire falls armed with camera and a little hope. A Dipper was sat on a rock beneath Apedale beck and a Heron stood in the shallow edges at the far bank. It reluctantly took to the air, slow wingbeats just managing to get it out the water and away. I headed over the limestone 'steps' and down to the first set of falls. Getting my feet wet I found a good place to sit and I waited there, legs dangling against a mossy boulder, for a couple of hours till dusk set in but nothing stirred, not even a noticeable rise in the pool beneath the falls.

On the way home I stopped at Ballowfields to see if any big trout had moved into the stream there. Too high and fast to see anything. It cant be long now before the fish head up this way so I plan to maintain the vigil in the spare time I get. In the meantime plenty of mapping and writing to be getting on with.