Restoring habitat for water voles

London Borough of Richmond upon Thames has been working with London Borough of Hounslow, FORCE and Pevensey Road Green Gym Rangers to improve the habitat in the Little Park and Pevensey Road Nature Reserve reach. This stretch of the River Crane has a somewhat remote, wildnerness feel to it, and up unti 2018 was home to a small population of water voles (Arvicola amphibius).  Water voles were historically commmon on the Crane but in recent times a combination of predation by the American Mink (Neogale vison) and habitat degradation has led to their disappearance.  The Crane Restoration and Engagement for Water Voles (CREW) project is seeking to re-establish some water vole colonies by drawing on funding from multiple sources and utilising local volunteers to help deliver the habitat enhancement works.   

As part of the enhancement effort, about 20 wooden deflectors have been installed in the channel by ‘hinging’ trees and fixing logs in the river. The deflectors disrupt the uniform flow of water in the artificially straightened channel, creating areas of faster and slower flow which over time will lead to the creation of natural features such as meanders, riffles, pools and sediment bars. These features provide space for aquatic vegetation to thrive, for fish sapwning and ultimately places for water voles to live.    

Along the banks the selective removal of vegetation has improved light penetration to both the woodland floor and to the water, reducing shading to allow a greater variety of planty and insect species to flourish. The project team has also reconnected some ditches in a glade at Little Park to the river, allowing for wet woodland formation, plus the creation of additonal flood strorage and areas of off line refuge for fish and water voles.  

The video below shows the various elements of the enhancement works: 

The plan for the next phase of the CREW project is to extend the works downstream through neighbouring Crane Park as far as Hospital Bridge Road. Water vole habitat enhancements have though already been delivered at Crane Park Island nature reserve by London Wildlife Trust, the Crane Park Island Volunteers and LBRuT. Here the ditches have been de-silted, scrub has been cleared and trees trimmed back.        

All the habitat enhancement works delivered to date will support the release of water voles in 2024.  Watch this space for more information on this.