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Notes: Abstract  We explored the key issues that are most likely to influence any set of guiding principles for developing biodiversity monitoring programmes in Australia's rangelands. We defined the Australian rangelands and came up with an overview of their climate extremes, land-use pressures and biodiversity loss, and then focussed on issues underpinning the design phase of any monitoring programme. Using Noss's 1990 framework of compositional, structural and functional attributes of biodiversity and its new revisions by others, we showed how the elusive, abstract concept of biodiversity can be used to identify many measurable attributes that can form a minimum and necessary set of indicators for any biodiversity monitoring task. We then described the steps in the monitoring process, with a particular focus on the reasons for monitoring biodiversity as they strongly influence the selection of indicators. We concluded by compiling a table of key issues as background information for developing guiding principles (Table 4). The list is by no means an exhaustive list for the design phase but it does indicate that considerable attention needs to be given to this phase when developing monitoring programmes. We have intentionally not addressed the equally important issues associated with the planning and delivery phases of developing a monitoring programme, as Wallace et al. and Watson and Novelly cover these in their papers in the present issue of Austral Ecology.

Notes: Abstract  The thermal ecology and structural habitat use of two closely related sympatric lizards, Carlia vivax (de Vis) and Lygisaurus foliorum de Vis, were examined in an open sclerophyll forest in subtropical Australia. Comparable mean body temperatures (Tb) and habitat temperatures (Thab) at the point of capture were recorded for both species. However, sex-related differences in the thermal variables for C. vivax, with females displaying higher temperatures than males, resulted in some significant differences in Tb and Thab between the species. Variation in Tb and Thab within and between species was unrelated to time of capture. The difference in Thab within C. vivax suggested that females were selecting warmer thermal environments than males. Both C. vivax and L. foliorum used most structural features of their habitat randomly as indicated by a similarity in canopy, shrub, ground, log and litter cover and litter depth between habitat surveys and random surveys. However, C. vivax displayed a preference for ground vegetation (height 〈1 m) and litter cover with significantly higher cover recorded where these lizards were captured compared with random surveys. There was no effect of sex on structural habitat used by either species. Thus, the warmer thermal environments selected by female C. vivax may differ from those selected by males in sun/shade patterns or additional habitat features not measured in the present study. Significant associations between specific habitat features and Tb matched broad habitat descriptions for C. vivax and L. foliorum. This suggests that thermal considerations have direct interactions with the structural habitat preferences of these species. The significant association between Tb and ground cover for C. vivax corresponded with the non-random use of ground cover by this species, whereas L. foliorum utilized all structural features randomly, despite an association between Tb and litter cover. The relative abundance or scarcity of individual structural habitat features may influence whether an association between those features and Tb is reflected in non-random patterns of habitat use.