James Bullock (Centre for Ecology and Hydrology), 19 Oct. 2016:

Population spread and the velocity of climate change

Climate change is leading to shifts in the geographic locations over which species can persist. Projections of climate change can be characterised in terms of the rate of this shift in climate space - summarised as the velocity of climate change. Simple mathematical models, integrodifference equations, are a useful approach to combine knowledge of species' demography and dispersal and the resulting projection of a species' rate of population spread - the wavespeed - can be compared against the velocity of climate change. If the wavespeed is less than the climate velocity, the species may not be able to track climate change. While this calculation involves simplifying assumptions, the wavespeed vs climate velocity comparison gives a straightforward warning about which species may suffer most under climate change. In making such comparisons, we are interested in calculating wavespeed for a wide variety of species. Unfortunately, there are demography and dispersal data for very few species. We have therefore used approaches including data synthesis, mechanistic dispersal models and statistical creation of "virtual species" to provide a more complete picture of variation in spread rates and risks from climate change.