Predicting mammal responses to pyrodiversity: From microbats to macropods

Abstract

Fire has shaped Australia's diverse mammal fauna for millennia. However, ongoing changes to fire regimes threaten native mammal populations, and a significant conservation challenge is to understand and promote desirable forms of pyrodiversity (variation in fire regimes). A way forward is to quantify how different aspects of pyrodiversity influence whole mammal assemblages and produce dynamic maps of species distributions to inform conservation. We aimed to determine and map how spatial and temporal variation in fire regimes correlates with a diverse mammal assemblage comprising macropods, microbats, rodents, small marsupials and a monotreme. We built species distribution models for 17 species against fire, climate and environmental covariates in fire-prone woodlands of semi-arid Australia. Spatial measures of fire included the area, diversity and configuration of landscape elements, and temporal measures included time since fire and fire frequency. Native mammals showed a variety of responses to pyrodiversity. Microbats were more likely to occur as time since fire increased, whereas rodents were correlated with recently burned areas. Small dasyurid marsupials were correlated with the area of older post-fire age-classes, while western grey kangaroo occurrence was positively associated with high diversity of post-fire ages. Our new approach, using predictive models to map mammal distributions in relation to spatial and temporal variation in fire regimes, provides outputs that managers can use to improve conservation planning. This enables the positive and negative effects of fire to be better understood and will assist in achieving desirable forms of pyrodiversity that meet the needs of whole mammal assemblages.