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We study the stability and synchronization of predator-prey
populations subjected to noise. The system is described by patches
of local populations coupled by migration and predation over a
neighborhood. When a single patch is considered, random
perturbations tend to destabilize the populations, leading to
extinction. If the number of patches is small, stabilization in
the presence of noise is maintained at the expense of
synchronization. As the number of patches increases, both the
stability and the synchrony among patches increase. However, a
residual asynchrony, large compared with the noise amplitude, seems
to persist even in the limit of infinite number of patches.
Therefore, the mechanism of stabilization by asynchrony recently
proposed by R. Abta et. al, combining noise, diffusion
and nonlinearities, seems to be more general than first
proposed.