National Water Vole Database and Mapping Project PART 1: PROJECT REPORT 2006-2015 Catherine McGuire and Deborah Whitfield December 2017

Executive Summary The National Water Vole Database and Mapping Project was established in January 2008 with the aim of collating and mapping available water vole data to:

• Assess population and distribution trends;
• Create a geographic information system (GIS) for water voles to support conservation measures and enable more strategic working at local, regional and national levels.
• Report against national BAP targets.

The project has collected water vole and mink data every year from volunteers, Local Environmental Records Centres (LERCs), the People’s Trust for Endangered Species (PTES), The Wildlife Trusts (TWT) and other suppliers in England, Wales and Scotland. Data is ‘cleaned’ and analysed using a methodology devised by Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust (BBOWT) to produce three tiers of mapping: alert, local key areas, and regional key areas. The aim of the alert and key areas maps is to identify the areas known to support water vole populations. A project report has been produced each year since 2009, using records from the previous five years (from 1st January of the first year to 31st December of the fourth year e.g. 1st January 2007 to 31st December 2011). This report presents an analysis of all water vole data from the last 10 years. Key Findings The most recent five-year reporting period (2011 to 2015) shows a slight increase in distribution on the previous five-year reporting period (2010 to 2014) and some successful conservation activity. Nevertheless, analysis of the full data set over the last 10 years has revealed that water vole distribution has declined. Click here to download the report