Effects of external and intrinsic factors on home range size in reed vole populations

Effect patterns of external and interior factors on home range size for reed voles Microtus fortis were measured using 2× 2× 2 factorial experiment design under the field enclosure. Results showed that average home range size for male reed voles was larger than that for females significantly. There was a significant positive correlation between home range size and body mass for males, but the home range size for females was not related to their body mass. Home range size for male and female reed moles were both related to population number negatively. There were no consistent trends in the effects of external factors on home range size of male and female reed voles. After the effects of population minimum number of known alive and body mass on home range size of males were considered, the effects of food on home rang size of males were still significant while the independent and interactive effects of predation and interspecific competition or 3 factors were all not significant. The independent effects of food, predation and interactive effects of three factors on home range size of females were all significant while interactive effects of food and interspecific competition were marginally significant, but independent effects of interspecific competition, interactive effects of food and predation were all not significant after the effects of population minimum number of known alive were considered. The results supported hypothesis that there were independent and interactive effects of external factors of population such as food, predation and interspecific competition and interior factors such as population numbers and body mass on home ranges of the voles.