Macroecological patterns of rodent population dynamics shaped by
bioclimatic gradients
Abstract
Long-term studies of cyclic rodent populations have contributed
fundamentally to the development of population ecology. Previous
research has shown macroecological patterns of population dynamics in
relation to latitude, but without disentangling the role of underlying
ecological and climate drivers. We collected 26 rodent time-series from
the tundra biome and assessed how population dynamics characteristics of
the most prevalent species varied with latitude and environmental
variables. While we could not find a relationship between latitude and
population cycle peak interval, other characteristics of population
dynamics had latitudinal patterns. The environmental predictor variables
provided insight into causes of these patterns, as i) increased
proportion of optimal habitat in the landscape led to higher population
cycle amplitudes in all species and ii) mid-winter climate variability
had negative impacts on cycle amplitude in Norwegian lemmings and
grey-sided voles. These results indicate that biome-scale climate and
landscape change can be expected to have profound impacts on rodent
population cycles and that the macro-ecology of such functionally
important tundra ecosystem characteristics is likely to be subjected to
transient dynamics.