In a world where the climate is now rapidly changing many important ecological processes will be affected. A challenge to population ecology as a predictive science will be to develop reliable predictions for the ecological impacts of these expected changes in climate. This requires that other factors than environmental stochasticity affecting population fluctuations such as density dependence, age-structure variation and demographic stochasticity are properly estimated and modelled. Here we show by reviewing a large number of studies of climate influences on the dynamics of bird and mammal populations that some general patterns appear.
I show that climate variation generates specific footprints in the population dynamics of most species that will strongly affect the viability of many animal populations. The robustness and generality of these dynamical fingerprints are likely to be high because they are well supported by general conclusions from stochastic population theory. Because the characteristics of these climate-induced footprints show large inter-specific variation, some species with particular life history traits will be more sensitive to climate changes than others. For instance, species at the slow end of the slow-fast continuum of life history variation seem especially vulnerable. Similarly, species affected by ‘bottom-up’ trophic interactions show a stronger climate footprint than predator-limited species. Our analyses show that both local climate and large scale climate phenomenon such as the North Atlantic Oscillation (NAO) can induce a common footprint in the population fluctuations that can be visible over large geographical areas. However, the characteristics of this footprint in space are different from the spatial scaling of the underlying climate driver due to the other factors affecting the population fluctuations. These patterns show that stochastic population theory can have wide applicability for developing reliable predictions of the ecological impact of future changes in the climate.