Succession in Bird and Plant Communities over a 24-Year Chronosequence of Mine Rehabilitation in the Australian Monsoon Tropics

Abstract

We compared the bird and woody plant communities of 2 to 24-year-old rehabilitation areas at Gove bauxite mine (20 km 2 ) in the seasonal tropics of northern Australia, where Alcan has maintained a consistent rehabilitation program since it began operation in 1974. Birds were censused every second month over 2 years in 30 widely separated 0.25-ha plots, representing five chronosequence stages. These were also compared with six (''off-mine'') plots adjacent to the mine, which represented the annually burnt open forest typical of the region. Short-lived Acacias dominated the early chronosequence stages, whereas eucalypts dominated in later stages. Mean avian species richness and abundance increased significantly along the chronosequence, with values for the oldest rehabilitation plots being very similar to those for the off-mine plots. However, analyses of similarity revealed that the bird communities of the oldest rehabilitation plots were distinct from those of the off-mine plots, indicating that succession in rehabilitation areas is not following a direct trajectory toward the native open forest surrounding the mine. Several hollownesting bird species were scarce or absent in the rehabilitation areas, probably reflecting the absence of older hollow-bearing trees. Many differences between the rehabilitation and the off-mine areas in vegetation structure, woody flora, and avifauna appear to be related to the exclusion of fire from the minesite. We recommend the initiation of experiments designed to assess the effects of fire on the biota but caution against the use of fires for the majority of rehabilitation areas.

Bird Functional Traits Respond to Forest Structure in Riparian Areas Undergoing Active Restoration

“…Bird assemblages can show large shifts in their composition according to the vegetation successional stage [22][23][24][25]. In accordance, descriptors related to forest structure such as vegetation height, total basal area or canopy depth can explain the richness and composition of bird species in restored sites [26].…”

“…Open restored sites have less trophic guilds, with predominance of granivorous species [33,34] that nest in the lower vegetation layer [33] and have low forest dependence [23,34]. As forests develop, functional group composition may change, with increasing abundances of forest-dependent and cavity-nesting species [23,33,34].…”

“…As forests develop, functional group composition may change, with increasing abundances of forest-dependent and cavity-nesting species [23,33,34]. For example, Santos-Júnior et al [28] found that the composition of bird functional groups in restored sites (<10 years) was similar to that of nearby small forest reference remnants but differed from that of a large forest reference site, likely due to greater environmental complexity and differential resource availability.…”

“…Intermediate stages of forest succession include birds from both open and forested sites, with dominance of generalist species [34]. The abundance of functional groups can vary widely among restored and reference sites even when they have similar levels of abundance and species richness [15,23,35]. However, few studies evaluated the responses of other habitat-related functional groups such as nesting habits and forest dependency.…”

Early Bird Assemblages under Different Subtropical Forest Restoration Strategies in Brazil: Passive, Nucleation and High Diversity Plantation

“…It is important to emphasize that in the dynamics of colonization, in some situations the bird assemblage converges rapidly to a structure similar to that of nearby forest fragments [65]. On other occasions the structure of the avian fauna may take different directions, with species adapted to the structure of the vegetation [12,66], generally influenced by the distance between forest fragments or by the change in the structure of the vegetation [23,67].…”