SPATIAL-BEHAVIOR AND POPULATION-DYNAMICS OF WOODLAND RODENTS

Population dynamics and spatial behaviour of the vole Clethrionomys gl areolus (Schreber, 1780) and the yellow-necked mouse Apodemus flavicol lis (Melchior, 1834) were studied for 7 years in woodland of Kampinos National Park, Poland. Mice were more mobile and less site-tenacious t han voles. Annual peaks ranged from 9 to 104 voles and from 4 to 62 mi ce per ha. The highest densities of both species were preceded by wint er breeding. The greatest movement range and the longest distance move d were observed in the years of low density, whereas in the high densi ty year both species were least mobile and most site-tenacious. Intens ive movements in the low density years led to early maturation, high t urnover 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 a ccounted for declining juvenile recruitment. Differences in movement p atterns between years of low and high density were coupled with differ ences in the autumn age structure and winter mortality of both species .