Fishy health checks in Shropshire

Our fish monitoring programme is now in full swing and our people have been undertaking lots of electric fishing surveys. On Wednesday 18th June we surveyed the River Onny near Onibury in Shropshire.

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Using electric current we surveyed 100m of the River Onny and caught:

127 juvenile Salmon

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18 Brown Trout

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3 Grayling

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2 large eels

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We measured all the fish and removed 3 scales from each salmon and trout in order for them to aged by our Brampton Laboratory.

This is a fantastic result! We counted salmon redds (nests) on this same stretch in October and November last year and saw salmon spawning, redds and dead kelts (fish that have died from exhaustion after spawning).

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The large numbers we caught shows the river in a great health and that not all the redds got washed away by the winter floods.

Staff from the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) joined us and took 30 salmon parr away to check if they have a parasite, Gyrodactylus salaris.

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It is a category one notifiable disease. The parasite has decimated rivers in Norway and CEFAS check each catchment in the UK every 5 years. Luckily no parasites have been found in our rivers to date.

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Measuring progress on the Horsbere Brook

Our fishery folk have been out on the Horsebere Brook in Gloucester undertaking an electro-fishing survey as part of our Fisheries and Biodiversity investigation programme. This was following work at Brockworth, between Mill Lane and the A46, to help address some of the issues that affect habitat quality and wildlife in the brook.

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The project manager, Cathy Beeching also invited members of the community and three Brook Wardens were able to attend.

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The brook is classified as poor overall for fish, under the Water Framework Directive, due to a lack of some fish species you’d expect to find such as bullhead and brown trout. This is partly because the shape of the river, and its banks, has been changed from their natural state over the years. Channel straightening, man-made banks, tipped rubbish and rubble have all reduced space for water and wildlife. Although the Horsebere Brook is a naturally active and changing watercourse, erosion and siltation has been exacerbated by water running quickly off neighbouring hard urban areas.

At the three survey locations, some eels, perch and roach fry were caught.

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Even two brown trout were found upstream of the habitat restoration site, showing a welcome improvement in fish species.

What were the Improvement Works?

As part of the Environment Agency led improvement works last summer we restored two cut off meanders. This lengthened the brook and created more habitat. One meander bypassed a section of concrete channel, which had scoured out a deep drop in the river bed and blocked fish movement.

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We also worked with Severn Trent Water to replace two failed and unsightly Storm Water Outfalls. The headwalls, which form the pipe outlet, were set a little further back from the bank, and constructed with more natural materials, to help them blend into the environment and reduce the speed of water entering the brook. At the same time the opportunity was taken to scoop out the river bank to restore a natural profile and wetland edge, and improve views and access to the brook, including more space for water in high flows.

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These interventions complemented an ongoing programme of improvements by the local community, with the Parish Council and Severn Vale Housing and Tewkesbury Borough Council, to stop fly tipping, and enhance the brook.

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We hope that all the volunteers who have planted trees, picked litter, maintained paths and made brushwood bundles for the restoration works will welcome the improving diversity of wildlife in this important urban brook.

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