Wildlife management aims and ecological processes: A case study of kangaroos

Abstract

Wildlife management can be for conservation, sustainable utilization, and pest control. This study describes broad-scale patterns in the annual population growth rate (r) in 2 large mammals that are the focus of wildlife management, namely the western gray (Macropus fuliginosus) and the red kangaroo (M. rufus). The study also aims to determine the processes that generate the patterns, in particular weather and harvesting. The mean annual population growth rates were not different from zero (r-0) consistent with no long-term trends and the stated kangaroo management aims of conservation and sustainable utilization. The frequency distributions of r were broadly consistent with the published data for several other small and large mammals. Western gray kangaroo population dynamics were weakly related to prior rainfall (and the prior Southern Oscillation Index, SOI) and harvesting. Population dynamics of red kangaroos were most related (ω1-=-0.53, R2-=-0.16) to the prior SOI, and to a lesser extent to prior rainfall and harvesting however the relationships were weak. Hence, the management aims were achieved but the ecological processes behind them describing the effects of weather and harvesting are unclear at the large landscape scale.