WTT Blog - Tagged with BACI

Connectivity is a recurrent theme of my blog posts. Last year I wrote about plans for notching some of the redundant low mill weirs on a tributary of the River Aire, local to me. Those plans will come to fruition in the next few weeks as Pete Turner (Environment Agency) and I have had our bespoke environmental permit consented to progress the works, so I’ll report back to show you how the channel is evolving. I also wrote about making connections and how Mike Forty’s PhD research with Ribble Rivers Trust had thrown up some really interesting results, especially regarding the importance of free movement for precocious parr; the published work is available here.

To communicate the worth of habitat restoration work (in supporting the Ecosystem Service approach & Natural Capital principles) to the wider public and to potential future funders, and thus maintain, increase and maximise the potential impact, there is an urgent need for some simple and accessible assessments that a broad audience can appreciate. I have proposed to use the concept of the food web in this context because: a) the knock-on effects of habitat degradation translate into food web alterations very quickly; and b) the food web is recognised by a broad swathe of society (and from a very early age). Hence, measures of food webs can be used as an engagement & educational tool that will increase the understanding and value of restoration projects, as well as a tangible and effective measure for funding applications.

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.