Of sheep and rain: large-scale population dynamics of the red kangaroo

摘要: 1. We analysed time-series data from populations of red kangaroos (Macropus rufus, Desmarest) inhabiting four areas in the pastoral zone South Australia. formulated a set priori models to disentangle relative effects covariates: rainfall, harvesting, intraspecific competition, and domestic herbivores, on kangaroo population-growth rate. 2. The statistical framework allowed for spatial variation growth-rate parameters, response covariates, environmental variability, as well spatially correlated error terms due shared environment. 3. most parsimonious model included all covariates but no area-specific parameter values, suggesting that densities respond same way across areas. 4. temporal dynamics were correlated, even after taking into account potentially synchronizing effect harvesting herbivores. 5. Counter-intuitively, we found positive rather than negative herbivore density rate kangaroos. hypothesize this is caused by sheep cattle acting surrogate resource availability beyond rainfall. 6. Even though our system studied, must conclude approximating resources surrogates such rainfall more difficult previously thought. This an important message studies consumer-resource systems highlights need be explicit about population processes when analysing patterns.