Field experiments on the movements of Apodemus sylvaticus L. using trapping and tracking techniques.

The movements of Apodemus sylvaticus were studied by trapping, tracking and direct observations in a woodland of newly planted conifers. Apodemus lived in groups or "super-families" with a dominant male (23-28g) in control. The dominant of each superfamily patrolled its territory (up to 6.4 acres) exploring it sector by sector, or more generally. Unfamiliar objects were carefully examined and labelled by urination. One dominant appeared to know when a neighboring dominant was absent and might then extend his area of movement. The other Apodemus mostly remained within the territory of their accepted dominant. Groups of subordinates moved together to preferred feeding grounds within the general territory, but outside their own individual home sites. The female Apodemus maintained compact ranges (average 0.2 acres), using one group of runways for a time and then disregarding them for another group. Females moved to new sites when populations were low (April to July) but had overlapping ranges in late summer when populations were high. Small monopolized zones were established by pregnant females. Factors influencing behavior and population control are discussed. There was no evidence of a year of peak population for Apodemus from 1963-1966.