Nature
River Mel Restoration Group
After a number of years of decline, the number of brown trout in the River Mel is on the increase. During the early months of this year more people are reporting that they have seen trout in both the Melbourn and Meldreth stretches of the river. So what has led to this increase? Trout breed in the winter months and in order to spawn successfully need fast flowing water and clean, well-oxygenated gravel in which to lay their eggs. Their decline can be traced in some part to historic dredging activities on the river. The Mel, along with many other streams in East Anglia, was dredged to make it wider and deeper, so as to accommodate flood flows and, in the case of Melbourn and Meldreth, to supply water to a series of water-driven corn-mills. Unfortunately, the dredging activities also removed much of the natural gravel bed of the river, while the wider deeper channel led to slow flows and the deposition of silt. By the time the Group started work in 2006 only a couple of short stretches of suitable gravel habitat remained. In short, much of the Mel no longer provided a habitat conducive to the life cycle of the brown trout. In order to encourage trout back to the river it was vital to provide a habitat that would support their breeding cycle. To this end, the Group created three artificial gravel shallows, called ‘riffles’, on a stretch of the river in Meldreth. This was not for the faint-hearted since we had zero experience when it came to riffle-building.
Fortunately we found experts willing to help us. The first riffle was installed under the watchful eye of the Ecology officer, while riffles two and three were installed with experts from the Environment Agency and the River Restoration centre respectively, both of whom brought a team of people out to help us as part of their corporate ‘away-day’ schemes. Each riffle took approximately 10 tonnes of specially sourced gravel, which was barrowed from the roadside, and along the riverside path by a team of hardy RMRG volunteers. It seems that the hard work has paid off. Water samples taken last summer by members of the River Restoration Centre showed that the riffles were teeming with the invertebrate species that provide a food source for young trout, and we hope that the increased sightings of larger trout means that the Mel is once again able to sustain a thriving population of wild trout. Working Party Dates: Saturday 18th June – Meldreth Saturday 2nd July – Melbourn Saturday 23rd July – Meldreth Saturday 13th August – Melbourn Saturday 3rd September – Meldreth All working parties meet at 9.15am for a 9.30am start and we endeavour to finish by about 12.30pm. In Melbourn we meet at the Pavilion on the Recreation Field and in Meldreth at 14 Flambards Close. For further information, please contact info@rivermel.com or telephone Maureen Brierley on 01763 262752.
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www.melbourncambridge.co.uk
