This issue features an Invited Feature Article by L. Eslami-Andergoli, P. Dale, J. Knight and H. McCallum about early warning indicators of abrupt regime shifts (also called tipping points), with a focus on intertidal wetlands ecosystems. A number of early warning indicators of regime shifts are assessed, including slowing recovery rates from perturbation, increased autocorrelation and variance, changing skewness and self-organised patchiness. This Invited Feature Article reviews the methods, and their limitations, for detecting such tipping points and thus providing an early warning. A combined approach of careful ecosystem modelling, detailed temporal and spatial data from field investigation and long-term multi-variables monitoring data, and non-linear statistical techniques is required.

The Editor