Not to be confused with a mouse, this is a bank vole. Mice have much longer tails and their ears are more prominent. Voles are normally well hidden, but when there is some easy food, especially in the winter, they can often be seen around bird feeders. When I saw these, there were several (at least two) bank voles running in and out of the undergrowth under the bird feeders. They move very quickly, but pause to grab some food.

The UK has three types of vole - the Bank Vole here, which lives in woodland, grassland and hedgerows, the Field Vole, which is more secretive and lives in the meadows, and the Water Vole, which as its name suggests, lives in and around water. Bank Voles and Fields voles are similar, but the bank vole has a proportionally longer tail.