Itchen Navigation - Flora and Fauna

Flora and Fauna

The Itchen Navigation supports a rich flora and fauna, and one benefit of the 5-year grant-funded restoration project has been the regular monitoring and publishing of reports to document this. Annual reports on the populations of birds, bats, otters, water voles and butterflies, damselflies and dragonflies have been produced, with occasional reports on other aspects, while the Environment Agency has produces fisheries reports. As part of the project, a number of engineering works have been carried out to stabilise the banks, and trees have been cut back to reduce the amount of shade and encourage the growth of marginal vegetation. In the case of the water vole survey, this had concentrated on the sections where work has been carried out, whereas the butterfly, damselfly and dragonfly survey has tended to cover the whole navigation. Vegetated berms containing marginal plants have been placed along the banks. The project has tried to avoid the installation of revetments, as the vertical faces prevent wildlife accessing the banks, but where a revetment is necessary to combat erosion, it has been built of oak and a berm placed in front of it to soften the edge.

In recognition of the fact that many people use the towpath to exercise their dogs, dog dips have been installed at Allbrook and Shawford. These provide easy access into the water for dogs, and owners are encouraged to only allow dogs to swim at these locations, to conserve the bank in other places. The water vole surveys have followed the best practice described in the Water Vole Conservation Handbook (2006), and have also recorded evidence of otter, brown rat and American mink populations. While carrying out the work, the surveyors have also counted sightings of kingfisher, heron, moorhen and coot. The bat survey recorded common pipistrelle, soprano pipistrelle, Daubenton's, noctule and serotine bats in 2011. Bat boxes have been erected near Allbrook, and there was some evidence that they were being used. The 2009 fisheries survey recorded large numbers of young Atlantic salmon in the lower river, but although fish weirs have been provided, wild parr were not recorded near Winchester. Above there, a large population of brown trout thrives. Eels were monitored for the first time in 2009, when their distribution was found to be variable.