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Aim: Climatic extremes and fire affect ecosystems across the globe, yet our understanding of how species are influenced by the interaction of these broadscale ecological drivers is poorly understood. Using a ten‐year dataset, we tested how extreme drought and rainfall interacted with time since fire (TSF) to shape bird species' distributions. Location: Semi‐arid mallee woodlands of south‐eastern Australia. Methods: We quantified the effects of climatic extremes on bird species' occurrence, species richness and incidence at 180 sites across three climatic periods—an El Niño‐associated drought (the "Big Dry"), immediately after La Niña drought‐breaking rainfall ("Big Wet") and three years following the La Niña event ("Post‐Big Wet"). We then compared species' responses with TSF across the three climatic periods using a chronosequence of sites from 1 to 117 years post‐fire. Results: La Niña rainfall had sustained impacts on species' occurrence. Over half of species increased significantly during the Big Wet. Despite three intervening years of below‐average rainfall, three quarters of these species remained comparably high, Post‐Big Wet. By contrast, less than half of threatened and declining species benefited from high rainfall. Responses of species to TSF were found to differ contingent on climatic conditions: almost twice as many species responded to TSF during the Big Wet and almost three times as many Post‐Big Wet, compared with the Big Dry. Across climatic periods, a majority of species showed preference for mid to older post‐fire vegetation. Main conclusions: Variation in responses to TSF is likely due to the effect of climatic variation on resources. We suggest that, at sites of different post‐fire age, interactions between TSF and climate may differentially influence both the availability and longevity of resources. Given climatic extremes are predicted to become increasingly severe with climate change, accounting for their influence on fauna–fire dynamics will require careful management of fire. [ABSTRACT FROM AUTHOR]

Aim A common assumption in fire ecology and management is that landscapes with a greater diversity of fire-ages will support a greater diversity of animal species (i.e. 'pyrodiversity begets biodiversity'). This assumption is based on the idea that landscapes with a more diverse fire history provide a greater array of post-fire habitats, leading to a greater number of species within the landscape. We assessed the hypothesis that pyrodiversity begets biodiversity by enhancing community differentiation (β diversity), resulting in increased landscape-scale richness (γ-diversity). We used reptiles as a case-study. Location The Mallee region of south-eastern Australia. Methods We used a study design in which 'whole' fire mosaics (12.6 km2) were the unit of replication. Study landscapes ( n = 28) were selected to represent a gradient in the diversity and extent of fire-age classes. We surveyed reptiles by using pitfall traps at 10 sites within each landscape (280 sites in total). Reptile data were used to characterize reptile assemblages at the landscape-scale in three ways: alpha (average within-site diversity), beta (between-site diversity) and gamma diversity (total diversity). Results The diversity of fire-age classes had little influence on the alpha, beta or gamma diversity of reptile assemblages. The properties of fire mosaics that most influenced assemblages were the extent of structurally important fire-age classes. The extent of long-unburned vegetation increased beta diversity but reduced alpha diversity of the total reptile assemblage, essentially cancelling each other out at the landscape scale. Main conclusions This study highlights the importance of considering multiple measures of diversity when exploring the influence of landscape properties on biodiversity, as 'null' results at the landscape scale (gamma diversity) can result from contrasting patterns in alpha and beta diversity. Using fire to create habitat mosaics, at the scale of this study, is unlikely to enhance the status of reptiles in the region. [ABSTRACT FROM AUTHOR]