Spatial and temporal drivers of small mammal distributions in a semi-arid environment : the role of rainfall, vegetation and life-history

摘要: A key task in ecology is to understand the drivers of animal distributions. In arid and semi-arid environments, this challenging because populations show considerable spatial temporal variation. An effective approach such systems examine both broad-scale long-term data. We used investigate distribution small mammal species ‘mallee’ vegetation south-eastern Australia. First, we examined data collected at 280 sites across Murray Mallee region. generalized additive mixed models (GAMMs) four hypotheses concerning factors that influence individual scale: structure, floristic diversity, topography recent rainfall. Second, from a single conservation reserve (surveyed 1997 2012) responses rainfall over period spanning broad range climatic conditions, including record high 2011. Small distributions were strongly associated with structure patterns, but relative importance these was species-specific. The mallee ningaui Ningaui yvonneae, for example, largely determined by cover hummock grass; whereas occurrence western pygmy possum Cercartetus concinnus most above-average Further, combination provided valuable insights. Bolam's mouse Pseudomys bolami uncommon during survey, surveys showed it responds positively Conceptual developed mammals temperate central Australia, respectively, not, on their own, adequate account distributional patterns ecosystem. Species-specific variation different more effectively explained qualitative differences life-history attributes among species.