The ecological impacts of modern global climate change are detectable in a wide variety of phenomena, ranging from shifts in species ranges to changes in community composition and human disease dynamics. So far, however, little attention has been given to temporal changes in spatial synchrony—the coincident change in abundance or value across the landscape—despite the importance of environmental synchrony as a driver of population trends and the central role of environmental variability in population rescue and extinction. Here we demonstrate that across North America, spatial synchrony of a significant proportion of 49 widespread North American wintering bird species has increased over the past 50 years—the period encompassing particularly intense anthropogenic effects in climate—paralleling significant increases in spatial synchrony of mean maximum air temperature. These results suggest the potential for increased spatial synchrony in environmental factors to be affecting a wide range of ecological phenomena. These eeffects are likely to vary, but for North American wildlife species, increased spatial synchrony driven by environmental factors may be the basis for a previously unrecognized threat to their long-term persistence in the form of more synchronized population dynamics reducing the potential for demographic rescue among interacting subpopulations.
Koenig, Walter D.; Liebhold, Andrew M. 2016. Temporally increasing spatial synchrony of North American temperature and bird populations. Nature Climate Change, Vol. 6(6): 4 pages.: 614-617.