Teresa J. Eyre

Testing landscape metrics as indicators of habitat loss and fragmentation in continuous eucalypt forests (Queensland, Australia)

Landscape metrics are widely applied in landscape ecology to quantify landscape structure. However, many are poorly tested and require rigorous validation if they are to serve as reliable indicators of habitat loss and frag-mentation, such as Montreal Process Indicator 1.1e. We apply a landscape ecology theory, supported by explor-atory and confirmatory statistical techniques, to empirically test landscape metrics for reporting Montreal Process Indicator 1.1e in continuous dry eucalypt forests of sub-tropical Queensland, Australia. Target biota examined included: the Yellow-bellied Glider (Petaurus australis); the diversity of nectar and sap feeding glider species including P. australis, the Sugar Glider P. breviceps, the Squirrel Glider P. norfolcensis, and the Feathertail GliderAcrobates pygmaeus; six diurnal forest birds species; total diurnal bird species diversity; and the density of nec-tar-feeding diurnal bird species. Two scales of influence were considered: the stand-scale (2 ha), and a series of radial landscape extents (500 m –2 km;78–1250 ha) surrounding each fauna transect. For all biota, stand-scale structural and compositional attributes were found to be more influential than landscape metrics. For the Yellow-belliedGlider, the proportion of trace habitats with a residual element of old spotted-gum/ironbark eucalypt trees was a significant landscape metric at the 2 km landscape extent. This is a measure of habitat loss rather than habitat fragmentation. For the diversity of nectar and sap feeding glider species, the proportion of trace habitats with a high coefficient of variation in patch size at the 750 m extent was a significant landscape metric. None of the landscape metrics tested was important for diurnal forest birds. We conclude that no single landscape metricadequately captures the response of the region’s forest biota per se. This poses a major challenge to regional reporting of Montreal Process Indicator 1.1e, fragmentation of forest types.

Measure it to better manage it: a biodiversity monitoring framework for the Australian rangelands

The need for broad-scale, long-term biodiversity monitoring to support evidence-based policy and management in the Australian rangelands is clear and pressing but, despite protracted discussion of this need, there has been little progress towards implementation. To prompt real progress, we propose a framework of spatially hierarchical and complementary components that together use a combination of direct and indirect measures of biodiversity and drivers: • Targeted monitoring; involving localised field-based monitoring of target species, addressing specific management questions. • Surveillance monitoring; involving broad-scale, field-based sampling of multi-taxa and a set of habitat and condition attributes. • Landscape-scale monitoring; providing regional to national-scale intelligence on habitat quality and trends in threats to or drivers of biodiversity, with data obtained using systematic ground-based and remote methods. The framework aims to provide information on the response of biodiversity to rangeland management that is relevant to regional, state and national jurisdictions. We believe the characteristics of the proposed framework address many of the pitfalls that often stall biodiversity monitoring in Australia. These characteristics include: clarification of the desired outcomes and management requirements; a strong collaborative partnership that oversees the administration of the framework and ensures long-term commitment; a conceptual model that guides clear and relevant question-setting; careful design and analysis aimed at addressing the set questions; timely and relevant communication and reporting; and, regular data analysis and review, providing an adaptive mechanism for the framework to evolve and remain relevant. The proposed framework can be incrementally implemented at a moderate cost, relative to current total expenditure in natural resource management in the Australian rangelands.