Fluctuations in an island bank vole population in the light of the study on its organization

A long therm study on the demography of an island population of the bank vole, Clethrionomys glareolus (Schreber, 1780), provided a deeper insight into the mechanisms underlying number fluctuations, also reproduction rate and survival of different components of the population structure. Among these processes only reproduction was regulated, which stabilized population numbers during the breeding season. Survival, being subject to random factors (except for particularly low population densities), was a destabilizing process leading to number fluctuations.