The Wood Mouse is one of the UK's most common mammals. I think she was after the sweet chestnuts that had been swept up from the lawn.
Mouse is welcome to forage in the compost bin, she is not a nuisance there as she would be inside one of my beehives. Mice are secretive little creatures, and they need to be because they are important food for owls, foxes and other wild creatures. Predation from domestic cats is a problem for them too.
More information :
http://www.wildaboutgardens.org.uk/wildlife/mammals/mouse.aspx
http://www.recyclenow.com/reduce/home-composting
