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Managing fire to achieve hazard reduction while providing for biodiversity conservation is complex in fire-prone regions. This challenge is exacerbated by limited understanding of post-fire changes in habitat and fuel attributes over time-scales commensurate with their development, and a paucity of empirical research integrating the effects of fire on these attributes. We used a 110-year post-fire chronosequence to investigate temporal development in habitat resources used by fauna, and fuels for fire in semi-arid Mallee vegetation, south-eastern Australia. Fire-history mapping previously limited investigation to 35 years post-fire. The patterns of temporal change over 110 years for 13 variables, representing key attributes of habitat and fuel, were explored using nonlinear mixed models and data from 549 sites. Most habitat and fuel attributes exhibited changes in abundance and rate of development over extended periods, emphasizing the importance of documenting post-fire dynamics over long time-frames. Further, developmental patterns were mostly nonlinear, indicating that a shorter temporal perspective (e.g. 20-30 years post-fire) may obscure, or provide an inaccurate understanding of, long-term changes. There were striking differences in the post-fire dynamics of some habitat and fuel attributes. Leaf litter and spinifex grass Triodia scariosa, which function as both habitat and fuel, increased rapidly after fire followed by a plateau or slow decline after 20-30 years. In contrast, live tree stems were not predicted to develop hollows until 40 years, after which time the density of live hollow-bearing stems, an important habitat feature, increased steadily. Synthesis and applications. Fire affects the development and abundance of resources over substantially longer periods than can be examined using fire-mapping based on satellite imagery. Our results demonstrate that post-fire changes in mallee vegetation influence fire hazard and faunal habitat in different ways. Critically, the cover/abundance of most primary fuel sources did not increase substantially beyond around 30 years post-fire; whereas important habitat attributes changed in ways that affect faunal occurrence for over a century. Fire management must explicitly acknowledge the potential for fire to affect fauna and fuel differently, and for these effects to operate over time-frames that may extend well beyond current understanding. [ABSTRACT FROM AUTHOR]

Abstract: Tree hollows are a critical, yet potentially limiting habitat resource for many animal species. Fire influences hollow availability, and the associated indirect effects on fauna can threaten the persistence of hollow-dependent species in fire-prone systems. We investigated the influence of two temporal aspects of fire regimes (time-since-fire, inter-fire interval) on hollow occurrence in a semi-arid, fire-prone region in south-eastern Australia. Empirical data on the characteristics of hollow-bearing eucalypt stems and fire-history attributes were compiled for 581 study sites. Mixed models were used to examine the relative influence of time-since-fire and inter-fire interval on hollow occurrence. Time-since-fire and inter-fire interval both affected the probability of hollow occurrence, but in different ways. Time-since-fire influenced the occurrence of hollows in live and dead stems. As time-since-fire increased, so too did the probability of live and dead stems containing hollows. Live stems did not provide hollows before 40years post-fire, while the probability of dead stems containing hollows peaked at 50–60years. Inter-fire interval influenced the availability of hollows in dead stems. Longer inter-fire intervals resulted in an increased density of dead hollow-bearing stems. In this region, hollow-dependent fauna will benefit from increased fire-free periods, both in terms of individual fire events and the intervals between repeated fires. These results highlight the complex way in which fire affects the availability of faunal habitat resources, and the extended time periods over which such influences operate. Understanding the effects of fire regimes on slow-developing habitat resources over long time-frames is imperative for sound ecological fire management. [Copyright &y& Elsevier]