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Transient synchronization following invasion: revisiting Moran's model and a case study

Formally Refereed
Authors: Ottar N. Bjørnstad, Andrew M. Liebhold, Derek M. Johnson
Year: 2008
Type: Scientific Journal
Station: Northern Research Station
Source: Population Ecology. 50(4): 379-389.


Synchrony in forest insect outbreaks is important because the resulting regionalized outbreak dilutes the regulating effects of natural enemies, reduces the landscape's ability to buffer the disturbance, exacerbates the economic burden on individual stakeholders, and overwhelms the logistical abilities of managers to suppress populations and mitigate impacts. Understanding the process of synchronization of dynamics is therefore a crucial aspect of understanding outbreak dynamics. We studied the second-order log-linear (autoregressive) model to ask what patterns of synchronization across invasion fronts may be expected from Moran's model. Generally, we show that the time to synchronization in the log-linear model is a complex function of a number of parameters of which the overall strength of regulation, the strength of delayed statistical density dependence, and the relaxation time seem to be of particular importance. Interestingly, while environmental correlation is the crucial determinant of the magnitude of asymptotic synchrony, it does not appear to influence the transient process of synchronization.


Autoregressive model, Defoliation, Gypsy moth, Lymantria dispar, Moran effect, Spatiotemporal population dynamics, Transient dynamics


Bj rnstad, Ottar N.; Liebhold, Andrew M.; Johnson, Derek M. 2008. Transient synchronization following invasion: revisiting Moran's model and a case study. Population Ecology. 50(4): 379-389.