Where development may affect water voles or their habitats, consideration should be given to the following courses of action:
Planning the development to avoid water vole habitats
This is the preferred course of action. As water voles confine most of their activities to within a few metres of water it may be possible to leave undeveloped areas around ponds or wildlife corridors along ditches or streams. These corridors have an additional important function of linking together water vole populations and are recognised as a useful contribution to nature conservation.
Exclusion or translocation from development areas?
Recent evidence suggests that excluding water voles from development sites by the "displacement method" (see Water Vole Conservation Handbook), is unlikely to be effective in many situations. Until further evidence becomes available, displacement is no longer generally recommended by Scottish Natural Heritage. It may still be applicable in certain situations, but evidence would be required in such cases to support the approach. Trapping and translocation is regarded as the better option. Best practice guidance on this method is available in The Water Vole Mitigation Handbook but note that retaining trapped animals over-winter in captivity should only be considered where no other option is available.
A licence from Scottish Natural Heritage will be required.
Development can sometimes provide opportunities for habitat enhancement by restoring degraded habitats and encouraging the return of a greater range of wildlife. For water voles, the restoration of vegetated bankside corridors to link fragmented populations could help to reverse local population declines or improve the viability of small populations. An ecological appraisal should identify such opportunities for positive works. Wherever possible, favourable management for water voles should be promoted through the adoption of a habitat management plan.
In addition to measures designed to protect and enhance the quality of the existing riparian habitat, the creation of new wetland habitat in the form of new SUDS ponds, extra lengths of waterway or even the manipulation of the flow regime to create better conditions for water voles can be all be highly beneficial in the right circumstances. As water voles occupy linear territories, maximising the sinuosity of a narrow watercourse, by creating a series of tight meanders instead of a short straight canalised section creates a considerable amount of extra vole habitat which can support a much higher vole population. In some cases, a short section of fast-flowing narrow burn in otherwise ideal water vole habitat could be slowed-down with the construction of a small weir to form pools or areas of slow-flowing water that are of more benefit to the voles.
Further detail on some of the above can be found in the Water Vole Conservation Handbook (3rd edition).
Any works that are likely to damage a water vole burrow or disturb a water vole within it will require a licence from Scottish Natural Heritage. A licence to disturb water voles may be required for any works proposed within 10m of an active water vole burrow, even if no physical damage to the burrow or its immediate vicinity (i.e the riparian strip 5 metres in from the water's edge) will occur. See Licensing for further information.
Last updated on Thursday 8th September 2016 at 10:19 AM. Click here to comment on this page