The timing and nature of floristic and structural changes to vegetation were documented during secondary succession in wet forests in the Victorian Central Highlands from 3 to > 100 years after severe disturbance by timber-harvesting or wildfire. A chronosequence of five forest age-classes was employed. Vegetation surveys were conducted in two 15 × 50 m sampling quadrats in each of 12 replicate sites in each forest age-class between April 2000 and June 2001. Frequencies of occurrence of 67 floristic variables (plant taxa, other vegetation elements and litter components) were used to distinguish among plant communities in the different forest age-classes. Structural comparisons were made among the age-classes using species richness, floristic variability (i.e. spatial heterogeneity), trunk diameter and stem density of Mountain Ash Eucalyptus regnans F.Muell. and heights of forest strata. Most patterns of change showed a clear unidirectional trend from the youngest to the oldest age-class. Much of the floristic change occurred within a few decades of disturbance, but some of the structural changes continued throughout succession. Vegetation changes were generally attributable to natural succession, but a few differences between young forests that regenerated after timber-harvesting and older forests that originated after wildfire were likely to be due to the different disturbance histories. The pattern of vegetation change during secondary succession in forests after severe disturbance can influence the pattern of forest use by birds. The findings of this study thus formed the foundation of an examination of the community and behavioural responses of diurnal birds to secondary succession.

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Some bird species cannot persist during early secondary succession after natural or anthropogenic disturbance of Australian Mountain Ash ( Eucalyptus regnans) forest, whilst others remain abundant throughout regeneration. To conserve bird species diversity optimally in such forests, we need to know, inter alia, exactly why the latter species can persist after disturbance. Using a chronosequence approach, we documented four facets of foraging in a suite of these persistent species effectively covering 100 years of succession in E. regnans forest disturbed by wildfire or timber harvesting, namely the foraging strata, locations, substrates and behaviours used. Most species showed plasticity in their use of foraging strata and locations during succession, but four exhibited some limited stereotypy in these facets. In contrast, use of foraging substrates and behaviours was largely invariant within species during secondary succession. We suggest that switching foraging strata and locations was probably critical to persistence of most of these bird species during secondary succession, given the marked variation in structural and floristic variables that characterises this regeneration process. Some plasticity in foraging behaviour repertoire and substrate use was probably possible, but not beneficial. Although some resident bird species’ populations were severely reduced by disturbance in these forests, a substantial subset of species was sufficiently flexible in choosing foraging microhabitats to persist throughout secondary succession at pre-disturbance abundances.

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