Effects of extra food on Peromyscus and Clethrionomys populations in the southern Yukon
Gilbert BS and Krebs CJ. 1981. Effects of extra food on Peromyscus and Clethrionomys populations in the southern Yukon. Oecologia. 51(3):326-331
Summary: If food supply limits density in rodent populations, the addition of supplemental food ought to increase population size. From May to September we added food on two hectare areas of white spruce forest in the southern Yukon. In 1977, we used oats with no measurable impact. In 1978 and 1979 we used sunflower seeds and doubled or tripled the population densities of Peromyscus maniculatus and Clethrionomys rutilus. Supplemental feeding with sunflower seeds increased juvenile survival. The breeding season ended at the same time on experimental and control areas, and the onset of maturity in juveniles was not affected by feeding. Survival of adult rodents was not improved by feeding. Immigration into sunflower seed areas was very high, and was the major factor producing the increase in population density. Body weight was not changed by feeding. Food supply is thus one factor limiting population density in these subarctic small mammals, but we do not know why supplemental food produces no more than a two to three-fold effect on densities.
- Type
- Journal Article
- Authors
- Gilbert, B; Krebs, C
- Units
- CAKN , DENA , YUCH , WRST
- Keywords
- body weight, Canada, Density, Diets, Foods, Growth, Kluane National Park, Mammals, Mice, Population Ecology, Small Mammals, Subarctic, Survival, Voles