Aim Extreme climatic events and large wildfires are predicted to increase as the world's climate warms. Understanding how they shape species’ distributions will be critical for conserving biodiversity. We used a 7‐year dataset of mammals collected during and after south‐east Australia's Millennium Drought to assess the roles of fire history, climatic extremes and their interactions in shaping mammal distributions. Location Grampians National Park, south‐eastern Australia. Methods We surveyed mammals at 36 sites along a ~50‐year post‐fire chronosequence in each of the 7 years. We modelled ten mammal species in relation to fire history, productivity and recent rainfall. Next, we examined the consistency of species’ fire response curves across each of three climatic phases relating to the Millennium Drought. Finally, we identified the optimal distribution of fire ages for small and medium‐sized mammal conservation in each of the three climatic phases. Results The majority of species were influenced by fire history, and all native species were negatively associated with recently burned vegetation. Seven of ten species responded positively to the end of the Millennium Drought, but six of these declined quickly thereafter. Species’ responses to fire history differed depending on the climatic conditions. However, the optimal distribution of fire‐age classes consistently emphasized the importance of older age classes, regardless of climatic phase. This distribution is in stark contrast to the current distribution of fire ages across the study region. Main conclusions Mammals in the study region face an uncertain future. The negative impact of drought, the short‐lived nature of post‐drought recovery and, now, the possibility of a new drought beginning forewarn of further declines. The stark contrast between the optimal and current fire‐age distributions means that reducing the incidence of further fires is critical to enhance the capacity of native mammal communities to weather an increasingly turbulent climate.

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Fire can promote biodiversity, but changing patterns of fire threaten species worldwide. While scientific literature often describes ‘‘inappropriate fire regimes’’ as a significant threat to biodiversity, less attention has been paid to the characteristics that make a fire regime inappropriate. We go beyond this generic description and synthesize how inappropriate fire regimes contribute to declines of animal populations using threatened mammals as a case study. We developed a demographic framework for classifying mechanisms by which fire regimes cause population decline and applied the framework in a systematic review to identify fire characteristics and interacting threats associated with population declines in Australian threatened land mammals (n = 99). Inappropriate fire regimes threaten 88% of Australian threatened land mammals. Our review indicates that intense, large, and frequent fires are the primary cause of fire‐related population declines, particularly through their influence on survival rates. However, several species are threatened by a lack of fire, and there is considerable uncertainty in the evidence base for fire‐related declines. Climate change and predation are documented or predicted to interact with fire to exacerbate mammalian declines. This demographic framework will help target conservation actions globally and will be enhanced by empirical studies of animal survival, movement, and reproduction.

Planned burning generates different types of pyrodiversity, however, experimental tests of how alternative spatial patterns of burning influence animal communities remain rare. Field tests are needed to understand the mechanisms through which spatial variation in planned fire affects fauna, and how fire can be applied to benefit biodiversity. We tested five hypotheses of how fire‐driven variation in habitat composition and configuration affects fauna at fine scales. Small mammal, reptile and invasive predator activity was monitored at 12 burnt and eight unburnt sites through the year following a large, planned burn in semi‐arid ‘mallee’ woodlands of southern Australia. We explored measures of burnt or unburnt habitat (‘habitat status’); amount of unburnt vegetation (‘habitat amount’); interspersion of burnt and unburnt patches (‘habitat complementation’); distance to external or internal unburnt vegetation (‘habitat connectivity’); and unburnt patch size and local vegetation cover (‘habitat refuge’). Generalized linear models were used to test the influence of each variable on capture rates of three small mammal and 11 reptile species; activity of the introduced red fox (Vulpes vulpes); and species richness of native animals. We found strong support for the habitat status hypothesis and moderate support for four hypotheses relating to spatial patterns of fire. Reptile assemblages varied between burnt and unburnt sites, and relationships were identified between abundance of one or more reptile species and each measure of spatial variation. Reptile species richness was higher at unburnt sites and at sites with more unburnt vegetation in the surrounding area. Sites that were less connected to unburnt vegetation had fewer reptile species. Mammals did not have clear relationships with fine‐scale fire patterns. Synthesis and applications. Application of planned fire to promote biodiversity is globally important. We show that retaining unburnt areas and well‐connected habitat refuges is important for reptile diversity. We also found that several species of small mammals and reptiles appear resilient to the fine‐scale patterns of planned fire experienced in this study, despite activity of introduced predators. The diversity of animals can remain relatively high in areas subject to planned fire, provided that internal and external habitat refuges are retained.

Small mammals are commonly surveyed using live trapping but the influence of weather conditions on trap success is largely unknown. This information is required to design and implement more effective field surveys and monitoring. We tested the influence of weather and moon phase on capture rates of small mammals in the Murray Mallee region of semi-arid Australia. We used extensive pitfall trapping data collected at 267 sites, totalling 54492 trap-nights. We built regression models to explore the relationship between the capture rates of five species and daily meteorological conditions, and across families of mammals, including dasyurids, burramyids and rodents. A relationship common to several taxa was the positive influence of high winds (>20km h−1) on capture rates. We also identified differences between taxa, with warmer overnight temperatures increasing capture rates of mallee ningaui but decreasing those of Bolam’s mouse. This makes it difficult to determine a single set of ‘optimal’ meteorological conditions for surveying the entire community but points to conditions favourable to individual species and groups. We recommend that surveys undertaken in warmer months encompass a variety of meteorological conditions to increase capture rates and provide a representative sample of the small mammal community present in a landscape.