The Effect of Supplementary Food on a Population of Wood Mice (Apodemus sylvaticus)

Previous work at Oxford has shown that the amount of natural food available to wood mice (Apodemus sylvaticus (L.)) influences their quality and survival. Smyth (1966) showed that breeding in winter often followed a good acorn crop, and Watts (1970) demonstrated that the provision of food for a field population could advance the start of the breeding season by at least 2-3 weeks. Populations of Apodemus are known to exhibit a high density over winter which declines over summer and then increases through the autumn (e.g. Miller 1958; Bergstedt 1965; Crawley 1970). Watts (1969) analysed these changes over a period of 18 years from trapping records in one area of woodland and concluded the following.