WTT Blog

This is the view from my office window. Of late, I have been lucky to see across the valley. When it has been sufficiently clear there has been a stark message staring me in the face. So, what’s wrong in this image? OK, it’s not a great image but then it was taken in blowing rain. The field (centre shot) has a similar slope / exposure as those surrounding it yet it is the only one veined with rivulets of water. It is also the only one under permanent livestock grazing as compared to the fields on either side through which stock is rotated regularly. The result is a reduced crop plant height, root structure (and probably diversity), and more compacted soils leading to serious (visible) overland flow during times of heavy rain. At the bottom of that field is a tributary of the River Aire; little wonder that the Aire is often occupying the full width of its floodplain (below).

The UK landscape is a mosaic primarily of agriculture interspersed with woodland, grassland, urban enclaves and veined with river networks and wetlands. We should all realise by now that this pattern in the landscape has a marked effect on 'ecosystem goods and services', the natural benefits that the environment provides to us, and particularly those associated with freshwater. How we use (or abuse) the land, i.e. influence the landscape pattern, and the downstream consequences to water quality are a focus of the current consultation on diffuse pollution to which WTT has already responded (and I encourage you to do so too).    

A new study of an urbanising but predominantly agricultural landscape in the US draws upon data from 100 Wisconsin sub-watersheds and has important implications for managing and restoring landscapes to enhance surface water quality, groundwater quality, and groundwater supply. The study considered the landscape pattern in terms of composition (the type and amount of particular patches) and its configuration (the layout of those patches); and while both appear to have some bearing upon freshwater services, the composition had a stronger influence on water quality and supply. 

Man-made barriers, obstacles, call them what you will, are commonplace along our waterways as we have (typically) in the past tried to harness or control the flow of water for our own use. Some of these installations were incredibly insensitive to the local and more widely spread ecology and physical processes in rivers and streams, not just the fish that might want free passage both up and downstream at all life stages, and in all seasons.

I recently spent an afternoon with Mike Forty, a PhD student registered at Durham University, and based with the Ribble Rivers Trust. His work, using telemetry to assess the efficiency with which fish can pass obstacles, has been enlightening, and some of the statistics he can rattle off are mind-boggling. His work was featured in the presentation that Jack Spees (Director of RRT) gave at our recent WTT Gathering and captured on video here. For example, the low cost baffle system that was installed on a previously almost impassable weir on Swanside Beck (picture to right) can now be ascended in 23 seconds (according to one sea trout), and several resident brown trout have been up and down it numerous times!

Eastburn Beck is a tributary of the River Aire in Yorkshire. It is typical of a northern freestone stream / river that has had a chequered history with industrialisation, and as a consequence, it has lost some of its vitality to the constraints of walled banks and a host of weirs. The walls keep long sections straightened and have allowed housing to develop on what would have been a far more sinuous, meandering floodplain. The weirs interrupt the natural progression of pool-riffle sequences and have choked the supply of gravels downstream.

The result is a series of impounded shallow sections with uniform depth, flow, and substrate on the bed, and little in the way of cover within stream. While some of the overly wide, shallow sections with plenty of jutting stones creating small pockets of turbulence provide excellent habitat for juvenile trout (and is also favoured by the local pair of dippers), there is a distinct lack of spawning, fry and adult holding habitat.

The first National Crayfish Conference to be organized in five years was held at Giggleswick School, almost on my doorstep. As I have supervised three PhD, and countless MSc and BSc student projects on invasive crayfish species during my 10 years at Queen Mary University of London, it seemed sensible to attend. I was granted time to do so on the WTT’s behalf since white clawed crayfish, the species we consider indigenous, and brown trout can both be considered flagship or sentinel species; that is their abundance / population health can tell us something about the quality of the ecosystem in which they reside. There are also other parallels of course, more of which below.