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In many parts of the world, livestock production and biodiversity conservation are important land uses of native grasslands in agricultural landscapes. Approaches to managing grasslands typically differ between production farms and conservation areas as they have different goals. Such differences may have consequent effects on the spatial and temporal habitat suitability for grassland fauna. In semi-arid grasslands of south-eastern Australia, the critically endangered Plains-wanderer (Pedionomus torquatus) is a grassland habitat-specialist bird that can occur on land managed for livestock production and conservation, but it is unclear if, and when, habitat suitability is affected in each land-use type. Here, we investigate how land-use type (livestock production, conservation) and rainfall (preceding accumulated rainfall) affect habitat suitability for the Plains-wanderer using 11 years of bird occurrence and remotely sensed habitat structure data. We found habitat suitability for the Plains-wanderer was driven by an interaction between land use and rainfall, with conservation areas supporting larger areas of preferred habitat structure during dry periods but less during wet periods. By contrast, Plains-wanderers were more likely to occur on livestock production farms during wet periods. We speculate this is because higher grazing pressure on livestock production farms was able to limit biomass accumulation and, hence, maintain more areas of preferred habitat structure. Our findings show that land used for livestock production can complement conservation areas by providing preferred habitat for the Plains-wanderer during climatic periods that promote grass growth. Furthermore, we highlight that land use and climate are important temporal drivers of grassland dynamics, and approaches to biodiversity conservation should consider how patterns of habitat suitability may shift across landscapes over time. Strategic, landscape-scale planning and effective agri-environmental initiatives will be critical to the future of grassland birds such as the Plains-wanderer.

Our understanding of the habitat needs of grassland fauna is often incomplete because of their cryptic behaviour. This presents a barrier to identifying important habitat attributes, whether these change at different spatial scales, and how this informs management decisions. Here, we use a critically endangered bird, the Plains-wanderer (Pedionomus torquatus, Pedionomidae), as an exemplar of the challenge of managing grasslands for cryptic species. Until now, almost all ecological knowledge of Plains-wanderers has come from the detection of nocturnally roosting individuals and habitat assessments at fine-scales that indicate open swards are preferred habitat. We GPS-tracked 13 adult Plains-wanderers to better understand diurnal habitat utilization in native grasslands of south-eastern Australia. Using these data, we assessed whether Plains-wanderers select for different habitat attributes during the day and night, and whether this varied according to spatial scale. At the fine-scale (< 1 ha), daytime foraging occurred in denser swards than those of nocturnal roosting sites. At the patch-scale (1–50 ha), Plains-wanderers selected for denser vegetation, with higher grass and lichen cover, whilst avoiding areas where structure was impacted by a high exotic plant cover. Plains-wanderers did not select habitat based on grassland type at the landscape-scale (>100 ha). We demonstrate that Plains-wanderers require grasslands with both open and denser swards to support foraging and roosting. In doing so, we address the biases associated with habitat assessments based on roost-only locations and extend known habitat associations critical to the successful management of the species. Our findings highlight that a precautionary approach to the classification of habitat requirements is warranted when uncertainty around habitat use of cryptic grassland fauna exists.

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