Populations of predators and their prey often show cyclic fluctuations in density, especially in northern latitudes. In many cases, the cycles of predator and prey are synchronous, and the search for mechanisms driving the cycles has been an abiding quest for ecologists. In some predator-prey pairs, the strength of the synchrony and the phase coupling of cycles vary geographically, and such variation allows ecologists to tease apart the underlying causes of the population cycles.
Haydon et al. model time-series data from Hudson Bay Company fur-trapping records for muskrat and their principal predator, mink, across Canada. The population dynamics of the two species show very similar geographical patterns, becoming increasingly coupled and synchronized from west to east. The causes of these patterns appear to be a combination of climate and topography, with the signature of the North Atlantic Oscillation more pronounced in eastern and central Canada than in the mountainous west. -- AMS
Proc. Natl. Acad. Sci. U.S.A., 10.1073/pnas.221275198.
