To investigate potential range shifts in a changing climate it is becoming increasingly common to develop models that account for demographic processes. Metapopulation models incorporate the spatial confi guration of occupied habitat (i.e. arrangement, size and quality), population demographics, and inter-patch dispersal making them suitable for investigating potential threats to small mammal range and abundance. However, the spatial scale (resolution) used to represent speciesenvironment dynamics may aff ect estimates of range shift and population resilience by failing to realistically represent the spatial confi guration of suitable habitat, including stepping stones and refugia. We aimed to determine whether relatively fi ne-scale environmental information infl uenced predictions of metapopulation persistence and range shift. Species distribution models were constructed for four small terrestrial mammals from southern Australia using environmental predictors measured at 0.1 ϫ 0.1 km (0.01 km 2 ) or 1.0 ϫ 1.0 km (1 km 2 ) resolution, and combined with demographic information to parameterise coupled niche-population models. Th ese models were used to simulate population dynamics projected over 40-yr under a stable and changing climate. Initial estimates of the area of available habitat were similar at both spatial scales. However, at the fi ne-scale, habitat confi guration comprised a greater number of patches (ca 12 times), that were more irregular in shape (ca 8 times the perimeter:area), and separated by a tenth of the distance than at the coarse-scale. While small patches were not more prone to extinction, populations generally declined at a higher rate and were associated with a lower expected minimum abundance. Despite increased species vulnerability at the fi ne-scale, greater range shifts were measured at the coarse-scale (for species illustrating a shift at both scales). Th ese results highlight the potential for range shifts and species vulnerability information to be misrepresented if advanced modelling techniques incorporating species demographics and dispersal inadequately represent the scale at which these processes occur.

The invasion of Pinus radiata from long-term established plantations is contributing to the degradation of fragmented and isolated remnants of native vegetation. Within the south-east of South Australia, the 20 vegetation communities that occur within 500 m of a plantation edge are at risk, including nine state threatened communities. To plan effective mitigation strategies, the current extent and distribution of P. radiata needs to be ascertained. High spatial resolution, multispectral QuickBird imagery and aerial photography were used to classify P. radiata within eucalypt and acacia woodlands, melaleuca shrubland, modified pasture and an Eucalyptus globulus plantation. Unsupervised classification of aerial photography gave the best result showing reasonable conformity with the observed distribution of P. radiata at the site scale. However, the 9.4 Ϯ 13.5 (SD) cover classified in the quadrats sampled for the accuracy assessment exceeded the 1.4 Ϯ 2.4 (SD) P. radiata cover determined from an independent dataset. Only 30.1 Ϯ 37.9% (SD) of trees within the quadrats and 9.40 Ϯ 13.49% (SD) of their foliage cover were classified. Trees detected by partial classification of canopy were positively correlated with both tree height and canopy diameter. Overall, the low detection rates were attributed to insufficient spectral resolution. Using higher resolution imagery, together with an object-based image analysis or combination of multispectral and airborne digital image classification, restricted to large emergent adult trees using LiDAR analysis, is likely to improve adult P. radiata detection accuracy.

In arid environments, grazing by exotic herbivores, including domestic livestock, can greatly influence native, small vertebrate assemblages. Whether the removal of livestock facilitates passive recovery of these assemblages depends on habitat condition and the species present. We explore changes in small mammal and reptile species richness, abundance, and composition in a degraded chenopod shrubland dominated by Acacia victoriae ssp. and open Acacia aneura (mulga) woodland destocked in 1976 and 1984, respectively. Data were obtained between 1997 and 2007, from two grazed and two ungrazed sites in each community. Species richness increased at a faster rate in ungrazed open A. aneura woodland, but did not differ significantly between ungrazed and grazed degraded chenopod shrubland. Subsequent analyses at a finer-scale detected disparate responses in richness and abundance for microhabitat. At this scale, a greater number of species-specific responses were also detected, including increased abundance of generalist species and decreased abundance of species requiring low cover. These results reiterate the potential for species-specific responses to livestock that are more apparent in particular microhabitats. Furthermore, this investigation provides evidence for the gradual passive recovery of small mammal and reptile assemblages in both communities, which is facilitated by the removal of livestock in open A. aneura woodland in fair condition, but not degraded chenopod shrubland in poor condition.

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