The Dales Rivers support fascinating ecosystems that rely on low nutrient watercourses in which to thrive. To understand these systems careful monitoring is required. The trust works in partnership with several other bodies including the Yorkshire Dales National Park Authority, Environment Agency and Natural England to survey the ecology of the rivers and understand how the populations of Brown Trout (Salmo trutta), macroinvertebrates such as mayfly and stonefly and other species within the ecosystems respond to land use and catchment processes. In order to improve river health and the ecosytesm they support the trust has targetted a number of issues that left unchecked would have negative effects on in-steam ecology.

Issue: Eutrophication, this leads to algal blooms and low oxygen levels in water courses and can change the ecology of upland rivers at its worse leading to severe fish kills.
Causes: the addition of phosphates from slurry, fertlisers and sewage treatment works.
Remedy: cathcment sensitive farming methods, tertiary treatment of sewage.

Issue: Fine sediment dleivery blocks up gravel beds reducing spawning success of fish species and habitat for macrioinvertebrates.
Cause: dranage and land management, stock access to river banks and intense rainfall.
Remedy: catchment sensitive farming methods, drain blocking.

Issue: rapid spate events and reduced summer base flows these both knock out spawning beds and gravel habitats and reduce available ahbitat in low flow conditions. This can then increase water temperature and exacerbate nutrient concentrations resulting in further eutrophication.
Cause: high density drianage and increased rainfall severity.
Remedy: block upland drains (grips), plant gills with native trees, contour planting and buffer strips.

Issue: Non-native species.
Signal crayfish (Pacifastacus leniusculus) have been introduced from the US and are decimating the native White Clawed Crayfish (Austropotamobius pallipes) by outcompeting them and as the vectors of crayfish plague that the native species has no immunity to.
Himalayan Balsam (Impatiens glandulifera) this plant is extremely invasive and spreads readily down river corridors. It grows on bank sides and shades out other species depleting native fauna. When it dies back it leaves bare soil underneathy which is susceptible to erosion which adds fine sediment to watercoarses.
Causes: transfers of species by Human intervention.
Remedy: increase biosecurity through national policy. Monitor and conserve native species and remove non-native species when possible.
It is this understanding of the ecology of the dales gained through monitoring that allows informed deceison making of restoration and conservation measures. The trust also follows advances in catchment management to ensure that we stay up to date. Work such as at Pont Bren that showed how contour planting can slow water movement across a landscape is now being transferred to dales catchments.
The trust recognises that the dales landscape has been shaped by farming for centuries. The myriad of uneven fields enclosed by lichen ridden grey limestone walls contain flower rich meadows and pastures. Livestock dominates farming in the upland dales with dairy herds, beef cattle and sheep grazing the hills and floodplains. It is these intricate details arising from land use combined with topography that have attracted tourists to the dales. Without farming the dales would be a poorer landscape.

The trust aims to work with farmers to further enhance the landscape and improve the biodiversity it contains. We recognise the importance of farming knowledge which stretches back generations and try to validate knowledge gained by remote sensing and modelling with farmers, gamekeepers and landowners who have detailed knowledge of the land they work.

The topography of the dales places controls on when and where a mode of land use becomes strongly connected to a water course and thus a possible diffuse pollution issue. On steep slopes that end at river banks slurry spreading is more likely to cause eutrophication of a water course. Heavy trampling by live stock is likely to become a source of sediment in rivers if there is a delivery pathway of surface flow connecting the source to a recipient stream.

By working with land managers it is possible to appreciate their knowledge and gain an understanding of the issues facing them in their day to day work. The trust creates these mutual relationships in the hope that farming and conservation of biodiversity are not mutually exclusive and in the hope that farming can remain viable for the foreseeable future.