Uncovering correlates of decline and critical refuges for a threatened terrestrial mammal.

Globally, the geographic ranges of numerous species are contracting. Identifying spatiotemporal patterns of threat impact can illuminate why species decline in some parts of their range but persist in others. We developed a correlative approach to identify species' response thresholds and locate ecological refuge areas associated with persistence to inform conservation planning and management. We integrated changes in realized niche characteristics for a threatened Australian mammal, the brush-tailed rock-wallaby (Petrogale penicillata), with the distributions of threatening processes and environmental features to identify predictors of extirpation and persistence. We used occurrence records to construct historical (2004 or before) and contemporary (2005-2022) species distribution models. We then determined differences in niche characteristics between areas of extirpation and persistence. We applied generalized additive mixed models to determine species-specific thresholds for extirpation, which we used to identify ecological refuges. Across the two periods, brush-tailed rock-wallaby habitat declined by 75%, resulting in realized niche shifts. Extirpations occurred where habitat distance to water increased, and red fox (Vulpes vulpes) densities and feral goat (Capra hircus) habitat suitability were relatively high. Relatively high topographic ruggedness and high minimum temperatures were associated with persistence. Species persistence was also positively correlated with increasing dingo (Canis familiaris) habitat suitability, and inappropriate fire regimes (e.g., more frequent fires than expected for a vegetation group), both of which have been suggested as threats to the species. Specific refuge locations were identified in southeastern Queensland and northern New South Wales. Our findings highlight the importance of quantitative species-specific threat assessments to prevent misguided conclusions from cross-taxa threat generalizations. As spatial data become increasingly accessible, our novel approach will provide practitioners with evidence on which to base fine-scale investigations. Our approach can be applied to other species undergoing range contractions.