EN
Population dynamics and spatial behaviour of the vole Clethrionomys glareolus (Schreber, 1780) and the yellow-necked mouse Apodemus flavicollis (Melchior, 1834) were studied for 7 years in woodland of Kampinos National Park, Poland. Mice were more mobile and less site-tenacious than voles. Annual peaks ranged from 9 to 104 voles and from 4 to 62 mice per ha. The highest densities of both species were preceded by winter breeding. The greatest movement range and the longest distance moved were observed in the years of low density, whereas in the high density year both species were least mobile and most site-tenacious. Intensive movements in the low density years led to early maturation, high turnover rates, and probably increased mortality. Low mobility and high site tenacity in the high density year enhanced population growth and suppressed maturation. Increasing density and cessation of breeding accounted for declining juvenile recruitment. Differences in movement patterns between years of low and high density were coupled with differences in the autumn age structure and winter mortality of both species.