• Biodiversity Action Plan
  • View the BAP
  • BAP Partners
  • Contact the BAP
  • General Action Plans
  • Habitats
  • Species
    • Otter
    • Water Vole
  • Progress and Reports

Water Vole (Arvicola terrestris)

Species Description

The water vole is a small semi-aquatic mammal that uses a wide range of fresh-water habitats. Important habitats for water voles within Northamptonshire include rivers, streams, ditches, ponds, canals, marshes, reedbeds, fens, gravel pits, lakes and reservoirs. The water vole is mainly herbivorous, feeding on grasses, sedges and rushes, with the predominant food being the common reed. Water voles excavate burrows in the riparian zone, with entrances usually being just above or below the water level, and sometimes on the top of the bank. The water vole has suffered a serious decline across Britain in recent years, and although the decline in Northamptonshire has been lower than the national average, this species is of critical concern.

Water Voles are thought to remain in only a few isolated pockets in Northamptonshire. The only remaining colony that could be described as a stronghold exists on the northern edge of Wellingborough, but the persistence of this requires more recent confirmation. Other sporadic sightings have occurred in the past 5 years, which suggests that a few scattered individuals may still be surviving elsewhere.

Current UK Status and Trends

On average 11.21% of sites across Britain were positive in 1996-98, representing a loss of 69.63% occupied sites since 1989/90.

Estimated Current Northants Resource

26% of surveyed sites in the Anglian region contained water voles in 1996-98, representing a loss of 58.82% over 8 years. Occasional new records occur, but old records become unreliable.

Progress Towards BAP Targets 2002-2007

Swanspool Brook designated as a County Wildlife Site because of the presence of water voles.

Lead Partner

The Wildlife Trust

Main Issues and Threats

• Predation by American mink (Mustela vison).
• Destruction of burrows and bank-side habitat by insensitive dredging and re-profiling methods.
• Reduction in suitable bank-side habitat caused by inappropriate management (poaching by stock, overgrazing, intensive mowing etc) or loss to development.
• Non-specific pest control procedures accidentally affecting water voles or misidentification of water voles as brown rats resulting in targeted pest control.
• Isolation of small populations causing reduced mobility and low genetic diversity.

General Strategy

• Promote suitable management of riparian habitat, funded primarily through the Countryside Stewardship Scheme (Advice can be provided by The Wildlife Trust, RNRP or FWAG).
• Suitable management involves retaining a patchwork of vegetation along banks, with cut and uncut sections. Vegetation should only be cut on one bank per year, and only between October and March. Riparian buffer strips should be created, with no grazing, cultivation or spraying within 6 m of the watercourse.
• Refer to best management practices when undertaking any engineering or habitat work.
• Habitat restoration across farmland at the catchment scale to include wetland creation, sympathetic ditch management, and use of riparian buffer strips.
• Creation of corridors of suitable habitat adjacent to existing colonies to enable populations to increase in size and range.
• Strategic mink control based on key site conservation.
• The specific target areas are Swanspool Brook between Wellingborough and Mears Ashby, Barnwell Brook through Barnwell, and RAF Croughton near Brackley.

Associated BAP Habitats

• Eutrophic Standing Waters
• Ponds
• Reedbed
• Rivers and Streams

Specific Management Required for Associated Habitats