Habitat improvements

Indian Balsam removal

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Indian balsam on the Rye in 2009 before clearance started

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The Rye 2013 almost completely clear of Indian balsam – allowing native plants to flourish

Indian Balsam is an annual invasive plant which is not indigenous. Its growth chokes the river and causes a number of problems. It has the ability to shoot its seeds many metres and when in the water, the seeds flow downstream. The Wye banks have been invaded in many areas and the local plants choked out. We started a project in 2010 to remove the indian Balsam before it seeds, starting at the rear of Wycombe Fire Station where it first appears.  The river is now almost free of Balsam as far along as Kingsmead, but there are always seeds around and ‘mop up’ operations are done every year by volunteers during June and July.
Read a comprehensive report about activity since 2010 Action taken to control Indian Balsam

                                                                                 River Flow modification

The following is an exract from a report by Stuart Keable, Fisheries Officer, Lower Thames catchment

Why Weirs on the Wye represent Barriers to Fish

The River Wye is only 10 miles long but has lots of weirs and other obstacles along its course.  Many of these are relics of water mills dating back to the industrial revolution and beyond.  Many act as a barrier to the movement of fish up and down the river. At the downstream end a weir severs the natural link between the Wye and the River Thames into which it runs.

Traditional solutions to fish passage problems at weirs and dams have normally been purpose-built to provide favourable hydraulic conditions for fish swimming in the upstream direction. Typical solutions include bypass channels, Larinier fish passes, brush passes and pool traverse passes. Such fish passes can be expensive to build, especially when added to an existing structure.

In response to the need for an alternative, a three-year research project into low cost modifications to some weirs to improve fish passage was undertaken.  This led to the development of ‘low cost baffles’ which can be bolted on to existing structures to facilitate fish passage.  Where the weirs concerned are gauging weirs (i.e. used by the Environment Agency to gauge river levels for flood alerts) these baffles can be attached without any impacts on flow gauging. The basic requirement of the baffles is to slow the water velocity over the weir by creating friction between the water and the weir.  A diagonal slot provides a path for the fish to climb the weir to the next stretch of river.

Low Cost Baffles are a cheap and easily installed fish ladder for sloping weirs

Two sites on the River Wye have benefitted from the installation of these simple fish ladders in 2016.

Hedsor Gauging Station (Bourne End)
Hedsor gauging station is located on the River Wye in Bourne End. It is a concrete gauging weir owned by the Environment Agency which cannot be easily removed or replaced.  This site is located below a bridge and is therefore difficult to view.  The baffles were installed in January 2016.

Dukes Meadow / Furlong Road Crump Weir
The crump weir (non-gauging) is located at the rear of Dukes Meadow off Millboard Road in Bourne End on the River Wye. The improvements were funded by the Environment Agency in support of their commitment to achieve good ecological status for the River Wye under the Water Framework Directive:

Which fish do we find on the Wye?  Good numbers but poor diversity.
The Environment Agency recently conducted a fish survey on the River Wye.  The results were interesting with only 2 species of fish being recorded at 2 different sites, one at Cores End and the other at Boundary Park.  We believe this is largely due to the ‘fragmentation’ of the river.  Basically it is broken into small sections which do not exchange fish because the fish cannot travel past the many weirs along its length.  The only fish capable of doing this are the native brown trout (Salmo trutta) which are widespread along the river.

Stuart Keable, Fisheries Officer with Brown Trout

 Brown trout are doing well in the chalk rich waters of The River Wye

If the many weirs along the Wye could be made passable to fish then we would expect many more species to be commonplace on the river.  Fish such as roach, chub, dace, gudgeon and even barbel, perch and pike would all do well in the chalk rich waters of the stream.

Chub, dace and perch should all be more widespread on the Wye.
We would also see the return to the river of the sea trout.  These are brown trout that decide to run out to sea and then return to spawn in the river of their birth.  With greater opportunity to travel freely up and downstream these beautiful fish will return to the river once more to live, as they did hundreds of years ago.

Riverfly monitoring

Riverflies live most of their lives as larvae on the bed of rivers and still waters. Together with freshwater invertebrates, they are at the heart of the freshwater ecosystem: a vital link in the aquatic food chain. Riverfly populations are affected by many factors, predominately water quality. This makes them powerful biological indicators for monitoring water quality. Regular monitoring provides vital analytical data.

Sampling the river

Revive the Wye volunteers are already monitoring 3 sites on the Wye and one of its back-streams. We want to recruit and train more volunteers so that we can regularly monitor more sites. If you are interested please contact us.

 

Sampling the river

Sampling the river

This photo was taken during one of the regular monthly riverfly monitoring tasks on Desborough Recreation Ground. It shows one of the volunteers who has been trained, about to sweep the riverbed for a sample to examine.

Results of sampling

Results of sampling

Most samples include at least one, and often several Bullheads, which seem to be quite content when caught, as they have a plentiful supply of riverfly larvae in the sampling tray, which they feast on whilst the identification task is in progress.

Restocking of the Rye Dyke

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At the invitation of the Rye Dyke Angling Club, Environment Agency Fisheries Officers carried out an electrofishing and seine netting survey on the Rye Dyke in November 2012, The results of the survey revealed a number of good sized carp (+/-20lb), with silver fish and other species sadly lacking. The EA is working with the angling club to help rebuild a sustainable fishery there. As part of this plan, the Rye Dyke was restocked in November 2013 with 5,000 Roach and 1,000 Tench from the EA’s Fish Farm at Calverton.

Next  Education and awareness

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