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1 Polish Journal of Ecology

1 2000

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Regional differences in dynamics of bank vole populations in Europe

Hansson L., Jędrzejewska B., Jędrzejewski W.

Polish Journal of Ecology

2000

Vol. 48, Suppl.

163-177

Fluctuation patterns of bank vole populations were reviewed for central and north-western Europe. Many fairly stable populations occur in central and western Europe while clearly cyclic populations, with an interval of 3-4 year between peaks, are typical for northern Fennoscandia. There is a transition zone around 60 stopni N. In forests in central Europe dominated by oak, and less so by beech and lime, bank vole populations demonstrate outbreak dynamics with peaks at 6-9 year intervals, related to mast seeding. Both cyclic and outbreak populations show pronounced annual variations in reproduction and survival. Community conditions are described for these types of populations and annual variations in food supply are denoted. Isolated (island) populations are characterised by generally high densities and high adult survival. Factors that have been suggested to explain the various dynamics differ: predation and food for cyclic performance, food alone for outbreaks and social factors within circumscribed populations.