Historic records testify that water voles were formerly a widespread species in Cornwall. The Victoria County Histories in 1906 record them as being “common in all suitable habitats throughout the county”. The Vincent Wildlife Trusts 1989-90 National Water Vole Survey recorded water voles at a single site on the River Bude although no latrines (piles of droppings developed as territorial markers) were found. The Environmental Records Centre for Cornwall and the Isles of Scilly has compiled a list of water vole records dating back to the 1960’s. These demonstrate a historic distribution which was countywide.
Water voles are Britain’s largest vole species. They are adapted to life in a water edge environment where their swimming ability allows them to both forage effectively amongst semi-emergent plant life and to avoid predators by “plopping” off the river bank and swimming away.
They typically live in burrow systems which they excavate in the banks or rivers, ditches, ponds or streams. In the future it is likely that water voles will only survive where populations are supported by active human intervention. This support will be to principally ensure the provision of suitable habitats and to control or eliminate predation by non-native North American Mink (Neovison vison). The reintroduction of water voles into habitats which are highly suitable and where strategic mink control on a catchment based or local level is practicable is therefore a recommended component of the species national conservation strategy.
The twenty two and a half acres of Bude Marsh is managed by Cornwall Council’s countryside department. A stated aim of the LNR management plan (2008 -2013) is to investigate the possibility of re-introducing water voles to the reserve. A mink survey – bridge checks for droppings or footprints and rafts to check wider distribution – was undertaken in the summer of 2012. No field signs of the species have been identified.
Bude Marsh and its surrounding river systems – the River Neet, River Strat and Bude Canal – provide a complexity of riparian habitat which is well capable of supporting a substantial water vole population. Large scale reintroductions of water voles are possible and the restored populations can be highly successful. The project began in 2013 with the release of captive bred juveniles. Its overall aim to restore a complete water vole breeding population over time and to maintain the whole catchment free of breeding mink. The only project of its type in Cornwall where water voles are now believed to be completely extinct.