The woodmouse is a characteristic rodent of deciduous woodland but it also lives on maritime sand-dunes. The population density of woodmice on sand-dunes is much lower than in woodland. Hue we test the hypothesis that this difference is due to the fact that woodland provides substantially more food than do sand-dunes. Our experimental approach was to provide supplementary food (wheat grain) to a sand-dune population for a period of 22 months and to compare demographic responses with a control population.
The supplemented population increased rapidly and reached a size 6–7 times that ofthe control population. The overall annual pattern of changes in density were similar in both populations with minimum numbers in late spring, maximum numbers in autumn and a loss of individuals over the winter. The woodmice receiving supplementary food bred earlier and for longer than did the control mice.