Post-fire trajectories of forest habitat structure depend on fire regime and environmental context

Fire is a key disturbance in forests around the globe. Fire shapes the structure in forests that provide essential habitat for wildlife. The post fire recovery of forests have often been characterised as a function of time since fire, overlooking the influence of additional fire characteristics, and post-fire environmental conditions. This knowledge is vital to support wildlife conservation under rapidly changing fire regimes arising from climatic extremes. In this study, we model the effects of fire severity, minimum fire intervals, and environmental context on the trajectory of wildlife habitat using structural data from 401 sclerophyll forest sites across 29 wildfires. Fire variables were included in the best supported models for all but graminoid cover. Fire severity strongly influenced post-fire trajectories of shrub cover, basal area of dead trees, tree density, and canopy cover. Within the top models, time since fire independently shaped four structures, with litter depth and shrub cover associated with positive recovery, while canopy cover and basal area of dead trees exhibited non-linear declines. However, most habitat structures were best explained by two- and three-way interactions among time since fire, fire regime attributes, and environmental conditions, highlighting the complexity of recovery dynamics in these forests. These findings demonstrate that time since fire alone is insufficient to model forest recovery and suggest that management decisions based on fire characteristics and environmental gradients will support more practical conservation actions.