Achievement

Regime shifts are abrupt reorganizations of ecological systems and the society that depends on them. Anticipating and predicting regime shifts has been elusive, but recent progress has been forthcoming in experimental systems by monitoring statistical indicators. We developed theoretical justification for a statistical indicator of a regime shift--extinction--based on a dynamical population model. We used both methods to warn of the transcritical bifurcation in long-term declining populations of bobwhite quail in an intensifying agricultural region. Our results corroborate the findings of microcosm experiments and are the first to detect the transcritical bifurcation in a wild population.