Density‐dependent reproduction causes winter crashes in a common vole population

Abstract

Common voles in western France exhibit three‐year population cycles with winter crashes after large outbreaks. During the winter of 2011–2012, we monitored survival, reproduction, recruitment and population growth rate of common voles at different densities (from low to outbreak densities) in natura to better understand density dependence of demographic parameters. Between October and April, the number of animals decreased irrespective of initial density. However, the decline was more pronounced when October density was higher (loss of ≈54 % of individuals at low density and 95 % at high density). Using capture‐mark‐recapture models with Pradel's temporal symmetry approach, we found a negative effect of density on recruitment and reproduction. In contrast, density had a slightly positive effect on survival indicating that mortality did not drive the steeper declines in animal numbers at high density. We discuss these results in a population cycle framework, and suggest that crashes after outbreaks could reflect negative effects of density dependence on reproduction rather than changes in mortality rates.

Moving forward in circles: challenges and opportunities in modelling population cycles

“…; Pinot et al . ) or maternal effects (Inchausti & Ginzburg ) can promote cycling. Using a combination of models and data, Kendall et al .…”

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Population‐level manipulations of field vole densities induce subsequent changes in plant quality but no impacts on vole demography

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Patterns of multiannual changes in the spatial structure of a bank vole (Myodes glareolus) population in hornbeam-oak forest

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