Bank and Land Erosion on Rivers – Natural or Aggravated?

Introduction

Agricultural practices have increased stream sediment load worldwide (Zimmerman et al., 2003; Naismith et al., 1996). Whilst fine sediment inputs to water courses can be a result of natural processes when the rates are enhanced they act as a pollutant (Waters 1995). In the UK much of the spatial and temporal variation in diffuse pollution is due to land management and there has long been concern that modern agricultural practice increases erosion rates and surface runoff (O’Connell et al., 2007). Soil cores have shown that sedimentation rapidly increases after woodland clearances. These increased rates of sediment delivery are especially noticeable when woodland has been cleared for conversion to agricultural usage suggesting that all UK river systems are prone to aggravated sedimentation. Following a rivers course through woodland into open farmland highlights the difference in erosion rates between land use types clearly showing the difference between natural and agriculturally enhanced sedimentation.

Process cascades and scale

Catchment scale studies of hydrology and processes reveal that hydrological response has been altered due to land use change; this has enhanced runoff response to rainfall events creating flashier systems (Bunn et al., 2010). As a consequence there is now a greater risk of fine sediment delivery. These changes in hydrological processes and sediment transfer rates are good examples of why shifts at the river scale should be viewed in the context of the wider catchment (Kondolf, 1995). Many hydrologists and ecologists now support large scale approaches and identify the catchment as the core unit for river management (Chorley, 1969; Newsom 1992; Burt and Pinay 2005). This shift in thinking has been driven by recognition that most degradation occurs as a cascade across large areas of the catchment which are often driven by catchment land use (Bond and Lake, 2003). Many temperate river catchments are now dominated by land use methods that enhance sediment transfers from land to streams due to vegetation conversion to pasture or the removal of riparian trees (Larsen and Ormerod, 2009). In such agriculturally-dominated catchments land management practices have been shown to alter soil surface roughness and subsequently the magnitude of erosion rates (Gilley et al., 2002). Associated impacts that are transferred to streams, due to enhanced surface flow and erosion rates, include the delivery of nutrients, pesticides, pathogens and heavy metals.

It is important to understand such effects in terms of a functioning (or malfunctioning) catchment that is subject to large-scale human influence. This is essential when aiming to identify the important impacts and contextualise these in terms of the landscape with all its processes and multiple impacts. Studies have helped uncover impacts from catchment scale management at the in-stream habitat scale and so highlight the process cascade from source to recipient stream. This shows how upstream management can place significant controls on river ecosystems through, for example, the delivery of sediments or changes in hydrological regimes. Such impacts transcend scale and move through catchments via pathways controlled by hydrological connectivity with negative impacts being noticeable at small-scale riffle habitats. Thus, understanding the cascades is essential for river managers.

Observing a single stream within a catchment may miss the pertinent information that a catchment approach captures by providing information on the relative condition of a river and its tributaries. Setting the incorrect spatial scale in which to explore systems can result in dubious findings. For example, Larsen et al. (2009) found that sedimentation of gravel beds was directly linked to eroding banks within 500m upstream. When they increased the scale of inquiry they discovered that bank erosion was negatively correlated with riparian and catchment woodland extent. Small-scale processes such as bank erosion place limiting factors on brown trout and it is now becoming increasingly accepted that such processes must be viewed in the context of upstream land use such as extent of riparian cover, stocking rates and woodland (Jutila et al., 2001; Lane, 2008; Larsen et al., 2009).

Land use impacts

Trimble and Mendel (1995) comment that cows can be important drivers of geomorphological change through trampling and poaching which expose soils and erode river banks. Theurer et al (1998) reinforce this when they argue that livestock farming results in bank erosion through poaching and subsequent deterioration of the grass sward, and thus root depth. Within upland rivers Theurer et al (1998, p.6) identified problems associated with enhanced delivery of fine sediments including, ‘accelerated stream bank degradation from livestock, major gullying of steep hillsides resulting from overgrazing by livestock and the introduction of grips.’

Soils are increasingly prone to erosion by livestock poaching and heavy machinery compaction which reduces infiltration (Marshall et al., 2009). This results in high rates of surface flow and increased Critical Source Areas and fine sediment delivery to streams. Sediment loss from agriculture is a cause for concern due to both on-farm practical and economic implications (Boardman et al., 2003) as well as the impacts sedimentation has on stream habitats and ecology (Owens et al., 2005; Theurer et al., 1998).

Ecological impacts

Fine sediment delivery is a key concern in drainage basins affected by anthropogenic disturbance (Wood and Armitage, 1997). In recognition of this it has been argued that the more pernicious controls on population are not driven by competition but habitat quality, especially habitat patches that have been degraded by anthropogenic impacts (Klemetsen et al., 2003; Ormerod, 2003; Gosset et al., 2006). For example fine sediment accumulation in gravel spawning beds (Ojanguren and Brana, 2003) negatively impact brown trout survival rates.

The early life stages of brown trout have quite specific requirements. Egg development requires gravel and pebble substrate (16 to 64mm) with a minimum dissolved oxygen concentration of approximately 5mg/l, though this can be as high as 7mg/l depending on the developmental stage of the egg (Louhi et al., 2008). Any sustained dip below these requirements reduces survivorship. Such requirements carry over to the fry life stage. However, habitat heterogeneity can enhance survival of fry by providing refugia and increasing habitat availability for prey species including macroinvertebrates. High macroinvertebrate abundance and richness is positively correlated with medium to large substrates which provide stability, interstitial space for refuge, oxygen exchange, attachment sites for filter feeders and diverse microbial, algal and detritus food supply (Allan, 1995; Wood and Armitage, 1997).

Through deposition within the interstitial space fine sediment reduces intergravel flow and oxygen replenishment. Particle size <1mm can result in a film on the redd surface inhibiting fry emergence (Kondolf, 2000) whilst very fine sediment <0.125mm can block the micropore canals in the egg membrane thus reducing waste transfer (Lapointe et al., 2004; Grieg et al., 2005; Julien and Begereron, 2006). Larsen and Ormerod (2009) showed that fine sediment addition to riffle habitats increased macroinvertebrate drift density by 45% and propensity by 200%. Whilst benthic macroinvertebrate composition remained the same population density declined in treated reaches by 30 to 60% and the effects remained consistent between seasons and streams. In short the infiltration of fines reduces the porosity of gravel matrix surfaces which can then reduce salmonid egg survivorship, habitat availability, refugia and also increase macroinvertebrate drift response (Grieg et al., 2007). If management of river systems is to become more sustainable then it is the root causes of degradation that must be addressed.

Restoration

How different types of land cover modify soil structure, surface flow and propensity for erosion must be understood in order for restorative measures to be taken. Marshall et al. (2009) found that shelter belts of trees as young as ten years old significantly reduce overland flow through 1) the presence of trees and 2) the absence of sheep. Mature forests are known to reduce peak flows due to a number of processes including evaporation of canopy interception, transpiration and an increase in soil water storage capacity beneath trees (Robinson and Dupeyrat, 2005). In comparison, pasture land reduces interception and, due to both livestock trampling and heavy farm machinery, soil compaction occurs lowering soil water capacity. This inevitably increases runoff rates in comparison to woodland given the same topographical conditions (Marshall et al., 2009). Zimmerman et al., (2003) found that lethal concentrations of fine sediment on fish could be reduced by up to 98% due to alterations in land use including the installation of riparian buffer strips, conservation tillage and the encouragement of a permanent vegetation cover. These findings support the work carried out at the catchment scale at Pont Bren (Jackson et al., 2008).

In order to prevent the delivery of pollutants such as fine sediment, substantial changes in agriculture are being discussed (Krause et al., 2008). These changes involve breaking the connections between CSAs and the river or changing the land use method that creates the initial problem. Such measures that can be carried out at catchment or field scale include gill planting, grip blocking, buffer strip creation along riparian zones which delimit terrestrial and aquatic systems (McGlynn and Seibert, 2003), moving gateways from the downslope section of fields to areas where water is less likely to accumulate or completely changing the farming method in some fields or farms. All of these methods would be appropriate in upland UK catchments but farmers require advice and grant input in order to manage such change.


References

Allan J., 1995. Stream Ecology: structure and function of running waters. Chapman and Hall, London.
Boardman J., Poesen J., Evans R., 2003, Socio-economic factors in soil erosion and conservation. Environmental Science and Policy, 6.
Bond N., Lake P., 2003, Local habitat restoration in streams: constraints on the effectiveness of restoration for stream biota. Ecological Management and Restoration, 4.
Bunn S., Abal E., Smith M., Choy S., FellowsC., Harch B., Kennard M., Sheldon F., 2010, Integration of science and monitoring of river ecosystem health to guide investments in catchment protection and rehabilitation, Freshwater Biology, 55.
Burt T. Pinnay G. 2005. Linking hydrology and biogeochemistry in complex landscapes. Progress in Physical geography, 29, 3.
Chorley R., 1969, Water, earth and man: a synthesis of hydrology, geomorphology and socio-economic geography. London : Methuen.
Gilley J., Risse L., Eghball B., 2002, Managing runoff following manure application. Journal of Soil and Water Conservation, 57.
Gosset C., Rives J., Labonne J., 2006, Effect of habitat fragmentation on spawning migration of brown trout (Salmo trutta L.). Ecology of Freshwater Fish, 15.
Grieg S., Sear D., Carling P., 2007, A review of factors influencing the availability of dissolved oxygen to incubating salmonid embryos. Hydrological Processes, 21.
Heathwaite L., Quinn P., Hewett C., 2005, Modelling and managing critical source areas of diffuse pollution from agricultural land using flow connectivity simulation. Journal of Hydrology, 304.
Jackson B., Weater H., McIntyre N., Francis O., Frogbrook Z., Marshall M., Reynolds B., Solloway I., 2008, Upscaling runoff from hillslope to catchment scale: a case study in an upland Welsh catchment. BHS 10th National Hydrology Symposium, Exeter
Julien H., Begereron N., 2006, Effect of fine sediment infiltration during the incubation period on Atlantic salmon (Salmo salar) embryo survival. Hydrobiologia, 563.
Jutila, E., Ahvonen, A. & Julkunen, M. 2001. Instream and catchment characteristics affecting the occurrence and population density of brown trout (Salmo trutta L.) in forest brooks of a boreal basin. Fisheries Management and Ecology, 8.
Klemetsen A., Amundsen P-A., Dempson J., Jonsson B., Jonsson N, O’Connell M., Mortensen E., 2003, Atlantic salmon Salmo salar L., brown trout Salmo trutta L., and Arctic charr Salvelinus alpines L.: a review of aspects of their life histories. Ecology of Freshwater Fish, 12.
Kondolf M., 1995, Five elements for effective stream restoration. Restoration Ecology, Vol. 3.
Kondolf G., 2000, Some suggested guidelines for geomorphic aspects of anadromous salmonid habitat restoration proposals. Restoration Ecology, 8.
Krause S., Jacobs J., Voss A., Bronstert A., Zehe E., 2008, Assessing the impact of changes in landuse and management practices on the diffuse pollution and retention of nitrate in a riparian floodplain. Science of the Total Environment, 389.
Lane S., Reid S., Tayefi V., Yu D., Hardy R., 2008, Reconceptualising coarse sediment delivery problems in rivers as catchment-scale and diffuse. Geomorphology, 98.
Lapointe M., Bergeron N., Berube F., Pouliot M-A., Johnston P.,2004, Interactive effects of substrate sand and silt contents, red-scale hydraulic gradients and interstitial velocities on egg-to-emergence survival of Atlantic salmon (Salmo salar). Canadian Journal of Fisheries and Aquatic Sciences 61.
Larsen S., Ormerod S, 2009, Low-level effects of inert sediments on temperate stream invertebrates. Freshwater Biology.
Larsen S., Vaughan I., Ormerod S, 2009, Scale dependent effects of fine sediment on temperate headwater invertebrates. Freshwater Biology, 54.
Louhi P., Maki-Petays A., Erkinaro J., 2008, Spawning habitat of Atlantic salmon and brown trout: general criteria and intergravel factors. River Research and Applications, 24.
Marshall M., Francis O., Frogbrook Z., Jackson B., McIntyre N., Reynolds B, Solloway I., Wheater H., Chell J., 2009, The impact of upland land management on flooding: results from an improved pasture hillslope. Hydrological processes, 23.
McGlynn, B., and Seibert J., 2003 , Distributed assessment of contributing area and riparian buffering along stream networks, Water Resources Research, Vol. 39
Naismith I., Wyatt R., Gulson J. and Mainstone C. 1996. The impact of land use on salmonids, a study of the River Torridge catchment. Report No. 30 to the National Rivers Authority
Newson M., 1992 Geomorphic thresholds in Gravel-bed rivers – refinement for an era of environmental change, in Billi, P Hey, RD, Thorne, CR & Tacconi, P (Eds) Dynamics of gravel-bed Rivers, J.Wiley & Sons, Chichester, UK, 3 – 20.

O'Connell, E., Ewen, J., O'Donnell, G. and Quinn, P. 2007, Is there a link between agricultural land-use management and flooding? Hydrology and Earth System Sciences, Vol. 11
Ojanguren A. and Brana F. 2003. Thermal dependence of embryonic growth and development in brown trout, Journal of Fish Biology 62, 580-590.
Oremrod S., Marshall E., Kerby G., and Rushton S., 2003, Meeting the ecological challenges of agricultural change, Journal of Applied Ecology, 40.
Owens P., Deeks L., Wood G., Betson M., Lord EE., Davison P., 2005, Variations in the depth distribution of phosphorus in soil profiles and implications for model-based catchment-scale predictions of phosphorus delivery to surface waters. Journal of Hydrology, 350.
Robinson, M., and Dupeyrat, A. 2005. Effects of commercial forest felling on streamflow regimes at Plynlimon. Hydrological Processes, Vol. 19
Theurer F., Harrod T. and Theurer M. 1998. Sedimentation and Salmonids in England and Wales, Environment Agency.
Trimble S., Mendel A., 1995, The cow as a geomorphic agent – a critical review. Geomorphology, 13.
Waters T. 1995. Sediment in streams: sources, biological effects, and control. American Fisheries Society Monograph 7.
Wood P., Armitage P., 1997, Biological effects of fine sediment in the lotic environment. Environmental Management, 21.
Zimmerman J., Vondracek B., and Westra J. 2003. Agricultural Land Use Effects on Sediment Loading and Fish Assemblages in Two Minnesota (USA) Watersheds, Environmental Management, Vol. 33.

YDRT 2011 Auction

Don't miss out...download the 2011 YDRT auction form at:

http://www.yorkshiredalesriverstrust.org.uk/YDRT%20Auctions.pdf

Further details below...and weekly updates to be posted here.

YOKSHIRE DALES RIVERS TRUST, POSTAL & EMAIL AUCTION 2011

YOKSHIRE DALES RIVERS TRUST
POSTAL & EMAIL AUCTION 2011

WHAT IS THE YORKSHIRE DALES RIVERS TRUST?

· Founded in 2004 the Yorkshire Dales Rivers Trust is a registered charity dedicated to river catchment management of the rivers Wharfe, Nidd, Ure and Swale being the major tributaries of the Yorkshire Ouse.

· Is an affiliated member of the national Association of Rivers Trusts and has only one paid employee. All other administration and work is conducted by volunteer trustees.

· YDRT has established very rewarding working relationships with landowners and managers, government and non-government conservation organisations with similar objectives, but is an independent charity totally reliant on funding from its subscribing associate members and grants from award making agencies.

AN INTRODUCTORY NOTE
From the chairman

YDRT held a postal auction for the first time last year and raised just over £1,000
from eleven lots generously donated by trust members. This year we would like to
build on that modest success and, with 23 attractive lots, it is hoped that we shall be able to at least double the return. This auction is very important to YDRT as a charity at this time – please bid generously. In addition to posting hard copies of the auction catalogue to all YDRT members, it is hoped that a wider public may also be attracted through making the catalogue available on our website: http://www.yorkshiredalesriverstrust.org.uk/YDRT%20Auctions.pdf - it may also be
downloaded as a document in portable document format (pdf) readily circulated to any
of your friends or acquaintances that you think may be interested in bidding.
On behalf of YDRT I would like to thank all the donors of lots for their very kind
support and generosity.

John Shillcock
Chairman

AN AUCTION TO BE CONDUCTED BY POSTAL OR EMAIL BID FOR THE BENEFIT OF THE YORKSHIRE DALES RIVERS TRUST BIDDERS PLEASE FOLLOW THIS GUIDANCE & CONDITIONS OF SALE CAREFULLY

Submission of bids:

Please submit bids by post or email to:
Yorkshire Dales Rivers Trust
East Farmhouse
Langthorne
BEDALE DL8 1PQ

nickbuck@lccweb.co.uk

The auction will commence Thursday 17th March 2011 and no further bids will be accepted after 10 am on Thursday, 14th April 2011.

· Please ensure that your name, address and telephone number are forwarded with the bid. A convenient form for postal bids is provided as below.

· AUCTION DAY – bids will be processed on Thursday, 14th April 2011. Every effort will be made to inform the successful bidders in writing during the following week. It is regretted that that YDRT cannot undertake to inform unsuccessful bidders.

· A starting price is stated against each lot and may be considered as a reserve price and the lowest that will be accepted for any lot. Where a guide price is provided this is the price which was obtained for the lot last year, or has been suggested as the “reasonable market value” by the donor. Auction participants may place “commission bids” similar to those accepted at a live auction. For example if a participant makes a bid of £100 for a lot with a starting price of £25 and there are no other bids for the lot, that bidder will secure the lot for £25. If bid of £30 is made by another bidder the “commission bid” will be secured at £35. The bids for all lots will be periodically updated on this blog to allow you to monitor bids and increase your offer should you wish.

· Yorkshire Dales Rivers Trust retains the right to refuse a bid even if it is the highest offered for a lot.

· The description of lots is based on information provided in good faith by the donors. Neither the YDRT nor the relevant donor can be held responsible for errors of description. If the donor of a lot is, for any reason, unable to make available the fishing offer YDRT shall refund the purchase price to the winning bidder, but shall have no liability for any consequent costs, loss or damages.

Notes for successful bidders

· Successful bidders will be notified by post. Once notified, please pay promptly by cheque payable to Yorkshire Dales Rivers Trust. If payment is not received in a reasonable time (two weeks) YDRT will phone the successful bidder, but reserves the right to offer the lot to the next highest bidder.

· Once payment is made the successful bidder will be advised of the donor’s contact details or be sent the prize awarded. In the case of sporting or dining lots, please contact the donor(s), as early as possible to arrange dates that are mutually acceptable. The donor may then also be able to advise when, for example, fishing is likely to be at its best or to offer some flexibility. All lots are to be taken during the 2011 season.

· In the case of fishing please ensure that you have established this contact to be advised of the limits of the water and the permissible angling methods BEFORE beginning to fish.

· Lots in this auction have been generously given by the donors for the benefit of Yorkshire Dales River Trust. They may not be resold or awarded as prizes for competitions without the permission of the donor and of YDRT.

· If anglers have fished outside the United Kingdom, please remember the continuing need to ensure that tackle, waders and equipment are thoroughly cleaned and disinfected before fishing to avoid the risk of introduction of Gyrodactylus salaris.

Auction Lots
Yorkshire Fishing

Lot 1 (Donated by A Roberts Esq.)

A day’s flyfishing for trout on the Kilnsey Angling Club water on the R Wharfe. This is an opportunity to fish the water of this prestigious club, one of the oldest in the country. A visitor ticket for the day during 2011 season with the conditions detailed will be issued to the successful bidder.
Guide price £25 (Starting price £25)

Lot 2 (Donated by the York and District Amalgamation of Anglers)

A Yearbook of the York DAA for the year 2011. The Yearbook is a permit valid from 1st January 2011 until 31st December 2011 which allows the holder to fish all the waters under York DAA control. This includes thirty stretches of prime Yorkshire river fishing on the Yorkshire Ouse, Derwent, Nidd, Foss, Rye and Seven; Pocklington and Selby canals; 11 miles of fishing on the Aire and Calder Canal and eight stillwaters, each with its own individual character. Also included is a permit to fish Laybourne Lakes at Hessay which is only usually available on payment of an additional fee.
Guide price £75 (Starting price £25)

Lot 3 (Donated by Sir Timothy Kitson)

Two days’ fishing on the R Ure for two rods on the 600 metre single bank beat (left bank) above Ulshaw Bridge. (Any legitimate angling method may be used. All salmon to be returned). Dates to be agreed with the donor. The donor has also generously included three bottles of wine from his personal cellar with this lot.
Guide price £200 (Starting price £50)

Lot 4 (Donated by Jervaulx Fly Fishers)

A day’s trout and grayling fishing for two persons on the Jervaulx Fly Fishers waters at Jervaulx, nr Masham. The fishery has 2 miles of the right bank of the R Ure and three small lakes with parking close to the fishing.
(Starting price £25)

Lot 5 (Donated by David Henderson)

A day’s fly casting instruction at Raygill Fishery, Lothersdale (stocked with Gold, Blue, Rainbow and Brown Trout) will be given by David Henderson (member of the Game Angling Instructors’ Association) at a mutually agreeable date during 2011. Alternatively a day’s instruction on the R Wharfe may be arranged entailing the purchase of a £30 Bolton Abbey permit.
Guide price £120 (Starting price £75)

Lot 6 (Donated by AJS Flyfishers)

Two days’ flyfishing for trout and grayling on the River Nidd near Knaresborough for two rods. Fishing will be in the Nidd gorge area at Scotton. The dates to be agreed with the Club Secretary who will explain the detailed water limits.
Guide price £150 (Starting price £100)

Lot 7 (Donated by Lord Bolton)

A day’s salmon fishing the R Ure on the Thoresby Beat of Bolton Castle Estate water near Leyburn. All salmon and seatrout to be returned to assist the conservation and species recovery programme. During the 2010 season this beat yielded nineteen salmon.
(Starting price £50)

Lot 8 (Donated by T Wheelwright Esq.)

A day’s flyfishing for trout and grayling on Gouthwaite Reservoir, Nidderdale for two rods and an evening meal for two at the Sportsman’s Arms, Wath, Pateley Bridge. Alternatively a single rod may take two separate days on agreement with the donor, but the meal is to be taken by two persons on the same evening. The date/s to be agreed with the donor.
Guide price £100 (Starting price £50)

Lot 9 (Donated by Ian Burdon Esq.)

A day’s fishing for salmon and trout on the R Ure for two rods and afternoon tea at the Jervaulx Abbey Tea Rooms. This Jervaulx Estate water is for the single, right bank and extends downstream for 2.5 miles from Harker Beck to Kilgram Bridge. The date and details of the water will be provided by the donor.
Guide price £150 (Starting price £50)

Lot 10 (Donated by Tom Ramsden Esq.)

A guided walk round Hackfall, the beautiful and impressive gorge below Grewelthorpe, followed by and evenings fly fishing on the R Ure for one or two rods.
(Starting price £25)

Lot 11 (Donated by James Harrison-Topham Esq.)

Two days trout fishing on the R Cover (or one day for two rods) to be taken in the 2011 season. This is a great opportunity to fish for wild brown trout and has to be taken when the water is in the right condition. Prior arrangements to be made with the donor who will notify keeper, farming tenant and explain the limits of the fishing.
Guide price £75(Starting price £25)

Lot 12 (Donated by Stuart Hopper Esq.)

A days fishing on the R Tees on Darlington Fly Fishers Club water near Barnard Castle around the “meeting of the waters” at the confluence of the rivers Greta and Tees. The river here holds brown trout, grayling and the occasional salmon and sea trout and a picnic lunch will be provided on a date by arrangement.
(Starting price £25)

Lot 13 (Donated by Adrian Thornton-Berry Esq.)

A day’s fly fishing for salmon for two rods on the R Ure on the Swinithwaite Estate water during September/October 2011. All salmon to be returned to the river.
(Starting price £50)

Lot 14 (Donated by R Bourne-Arton Esq.)

A day’s flyfishing for salmon and seatrout on the Tanfield Estate water, West Tanfield, Ripon. All salmon to be returned; two fresh seatrout may be killed. The date and details of the water will be provided by the donor.
Guide price £100 (Starting price £50)

Lot 15 (Donated by Ian Long Esq.)

A day’s still water fly fishing for rainbow trout on the Nderit Fishing Lake, Skeeby, Richmond for two rods. Two fish may be retained by each rod and the owner advises that the lake fishes well earlier in the season.
Guide price £50 (Starting price £25)

Lot 16 (Donated by Nidderdale Angling Club)

A week’s (seven days) fishing for two rods for brown trout and grayling on the Nidderdale Angling Clubs waters on the River Nidd and Scarr House Reservoir. This fishing is in the heart of the Nidderdale AONB with excellent accommodation and ready access to the Yorkshire Dales National Park. Details of the fishing will be made available by the Secretary of the Nidderdale AC.
(Starting price £50)

Lot 17 (Donated by A Lawson Esq.)

A day’s fly fishing for one rod on the Appletreewick Barden and Burnsall AC water on the R Wharfe and a bar lunch or evening meal at the New Inn, Appletreewick.
(Starting price £30)

Lot 18 (Donated by the Eden Rivers Trust)

A book of ten tokens for the Eden Rivers Trust “Go wild” angling passport scheme valued at £25; and an unframed map of the River Eden Salmon Pools. Bidders are advised to refer to www.edenriverstrust.org.uk to obtain the details of the passport scheme for fishing on 28 challenging wild trout beats on the River Eden system.
Guide price £50 (Starting price £25)


Other attractive lots

Lot 19 (Donated by R C Compton Esq.)

A Family Season Ticket to Newby Hall and Gardens, Ripon admitting up to two adults and three children from Easter to October 2011. This most generous offer will allow the successful purchaser to make periodic visits to see the gardens and house a various time during the summer.
Guide price £44 (Starting price £30)

Lot 20 (Donated by Michael Fox, The Buck Inn, Thornton Watlass

A hearty Sunday lunch (£25 voucher) for two at the Buck Inn, Thornton Watlass, nr Bedale. The landlord will be pleased to advise when there is a home cricket match to watch after dining.
(Starting price £25.00)

Lot 21 (Donated by the Ripon Spa Hotel)

A three course Sunday Lunch for 4 persons (to the value of £61.80) to be taken before the end July 2011. This generous offer excludes Bank Holidays and some other days such as Mothers’ and Fathers’ Days.
(Starting price £50)

Lot 22 (Donated by the Ripon Spa Hotel)

Croquet Sundowner for up to 4 persons to be taken April to October 2011. An introduction to the game or a fun evening for more experienced players. Enjoy a croquet game, tuition with England Ranked Players, and Pimms and Canapes.
(Starting price £25)

Lot 23 (Donated by the Yorkshire Agricultural Society)

A voucher for a Family Day Ticket (admitting two adults and two/three children) to the Great Yorkshire Show to be held in Harrogate on 12th to 14th July 2011.
Guide price £58 (Starting price £40)


Notes. By convention the description of river banks as left or right is when facing
downstream. Successful bidders are reminded that an EA rod licence is required
before fishing in England.


YORKSHIRE DALES RIVERS TRUST
Postal and email Auction 2011
Postal Bid Form: Postal bids are to be sent to Yorkshire Dales Rivers Trust, East Farmhouse, Langthorne, Bedale, North Yorkshire. DL8 1PQ
(email nickbuck@lccweb.co.uk )
to arrive before 10.00 am on Thursday, 14 April 2011.

I have read the guidance and conditions of sale in the Yorkshire Dales River Trusts 2011 Auction Catalogue and make the following bids in accordance with these.

Name ………………………………………………………………
Signature …………………………………………………………….
Address and post code …………………………………………………………
Telephone number ………………………………… Email address …………………………………….
Lot number Maximum bid (£)
Successful bidders will be notified by post during the week after the auction has
closed. Payment is to be made by cheque payable to Yorkshire Dales Rivers Trust. On
receipt of payment the contact details of the donors will be provided.

The Yorkshire Dales Rivers Trust
Registered in England as a company limited by guarantee No 5220147
and as Charity No 1107918

Ecology of rivers

The ecology of a river changes as you move downstream. The river continuum concept describes this. Rivers ecosystems were once seen as discrete entities. An ecosystem in the middle reaches was different and seperate from ecosystems up and downstream. Now the river is seen as a continuum with gradual changes as you move downstream. All ecosystems within a river are linked to those above and below. This could be through the spiralling of nutrients as they move with the current and cycle through the ecosystem or through the movement of energy and nutrients as fish and other taxa migrate upstream.

Whilst this shift in ecosystem type is seen as a continuum if we chose an ecosystem from the lower reaches of a system and compared it to one from the upland headwater sections they would appear as discrete and unconnected. For example the number and type of collectors would be completely different with the lower reaches being composed of species that can tolerate low dissolved oxygen levels. Shredders and grazers would be absent from the lower reaches but very apparent in the upland river system.

The movement of matter from the upland system to the lower system connects the two. And salmon or trout may connect matter whenthey smolt to migrate coastal zones and headwater streams. These long range migratory species transport nutrients between different sections of a river. Observing these changes is fascinating, trying to understand them as part of a continuum is complex. But rivers are the result of numerous intercating processes that link apaprently discrete sections and draw nutrients in from land based ecosystems. Conversely rivers deposit nutrients onto the land whenever they flood and indirectly transfer nutrents through species such as bats, herons and kingfishers. A river is never isolated, it is a response to processes on the land and is connected along its course and to the floodplain both in time and space. Rivers connect land, freshwater and sea.

Species found in the dales rivers

Some of the species found in the upland rivers of the Yorkshire Dales.

Brown Trout



Brown Trout Fry



Bullhead





Stone Loach





White Clawed Crayfish





Cased Caddis Fly



Minnows

Fish passes

Many of the Yorkshire rivers have endured an industrial past that reduced their biological diversity. There are stories that during the industrial revolution the Aire was so heavily polluted on its course through Leeds that it's surface could be set on fire. Thankfully recent years has seen a more enlightened attitude and our rivers have see steady improvements, with some unhelpful dips after pollution events. There are still historic headaches that river managers have to tackle. All the Yorkshire rivers are dotted with weirs built to service the old mills. Whilst these have become a part of the aesthetic nature of riverscapes they pose problems for migratory species including lamprey, eels, salmon and trout that have to navigate their way upstream against barrier after barrier that impedes their rout. In low flows the fish can become trapped behind the smaller weirs. In some locations on the Wharfe, such as at Otley, the weirs effectively stop upstream migration of fish and have drastically altered the food webs of the upstream river system.



The Yorkshire Dales Rivers Trust have recently worked in partnership with the Environment Agency to develop a fish pass with photographic recording equipment at Boston Spa, on the river Wharfe. The pass is now up and running and it is hoped it will enable safe upstream migration for salmon, trout, eels and lamprey. The camera equipment will record each fish that navigates the pass to supply important data on fish movement. Ideally we would aim to provide all the significant unnatural barriers with similar passes but the cost is prohibitive so development of fish passes has to be very selective. In the meantime each fish pass is one more battle won to help improve the river ecosystem.

River restoration

This is an exciting time to be involved in river ecology. Not only is river restoration becoming more research focused but the river itself is now seen as a system directly connected to landscapes by numerous processes and feedbacks. These riverscapes are constantly interacting with landscapes through hydrological connectivity and interspecies relationships meaning that the river is an integral component of the wider ecology of a catchment. More than this the morphology, ecology and quality of a river is governed by processes that work at catchment scales. For example in the headwaters of a stream it is the hydrological flow paths emerging at the upper reaches of the landscape that govern instream flow rates, discharge, sediment and nutrient delivery, river morphology and finally in-stream ecosystems.

In the past this lack of spatial context has often resulted in restoration that fails due to rivers not being viewed as am emergent response of the catchment. Tackling eroding river banks is a case in point. Management and restoration has often focused on the immediate surroundings of the issue, such as putting in place buffer strips, shoring up or reprofiling the bank. This is despite eroding banks being a symptom of upstream processes such as soil compaction, drainage or deforestation which all increase the speed at which water reaches the channel network and thus the erosive power of a river.

Now that these connections are being made river restoration is becoming process orientated and thus more likely to be succesful. Whilst this is exciting it also poses numerous difficulties. One such issue is that working on one location can result in the need to work with multiple land owners (as the focus shifts to upstream processes) some of whom are more receptive then others. This requires skills that go beyond knowledge of river systems into social science and negotiation and may require teams of multi-disciplinary practitioners in order to develop plans and inform land managers. Where such teams are in place river restoration is becoming more succesful and populations of indicator species such as salmon and trout are becoming re-established.

Winter in the Yorkshire Dales

Winter has hit the dales in a way it hasnt for decades. The riverscapes are surrounded in white that glistens in the low winter sun. Sheep huddle together behind walls waiting for deliveries of food that arrives by tractor which, despite their traction, also slip across the surface. The rivers are running low as all the precipitation is stored in snow and ice, the freezing nights keeping water locked up.

Cars have deep coverings of snow and roads look like gorges as the ploughs scrape them free of snow leaving steep edges on either side. The forecast suggests we have at least two more weeks of this and with drifts already reaching above head height the next days promise impresive sights.



The thaw is held up by the sub zero temperatures dipping to -8 in the dales and colder still the further north one travels. When this huge store of water eventually flows the rivers are set to rise substantially. The worst case scenario for those living in towns downstream of here is a rapid temperature rise coupled with rain. Such conditions will undoubtedly lead to flooding, and misery, for many.

Research into land management suggests that compacted soils and extensive drainage exacerbates flooding by shifting water rapidly from land to river resulting in sharp spikes in the hydrograph. The key to the next few years, as we move towards the prescriptions of the EU Water Framework Directive, is to understand how land management effects water and more importantly identify methods for improving conditions whilst making sure upland farmers do not lose income. This is an exciting time for freshwater ecology as local scale perspectives are stretched to the catchment scale which provides many of the controlling factors on river ecology and quality.

The incredible thing is that the whole country is white, smothered in deep drifts and layers of weeks of snow. Satelite photos from NASA display this strange image of the UK. It looks like not only Yorkshire rivers are at risk. In the meantime the landscape looks fantastic and we all hope the thaw occurs in a slow, steady manner.

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!

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.