Broad scaling region in a spatial ecological system

The ubiquity of scale-free patterns in ecological systems has raised the possibility that these systems operate near criticality. Critical phenomena (CP) require the tuning of parameters and typically exhibit a narrow scaling region in which power laws hold. Here we show that an individual-based predator-prey model exhibits scaling properties similar to CP, generated by a percolation-like transition but with a broader scaling region. There are no drastic changes in ecological quantities across this critical point and species coexist broadly in parameter space. The implications of these findings for the stability of ecological systems “near” criticality is discussed. © 2003 Wiley Periodicals, Inc.