MEASURING RESILIENCE IN STOCHASTIC-SYSTEMS

This paper develops mathematical and statistical techniques for measur ing the resilience of inherently stochastic ecological systems. To cor respond to the deterministic idea of resilience measured by the return time to equilibrium following perturbation, resilience in stochastic systems is defined as the variability in population densities relative to environmentally driven variability in population growth rates. Sto chastic resilience defined in this way is calculated from a community matrix describing the average interaction strengths within and among s pecies. The procedure to calculate stochastic resilience is demonstrat ed on simulated data sets consisting of time series of population dens ities. The simplicity of the procedure makes it a potential tool for a pplication to a wide range of ecological communities.