Search

Summary: This paper describes advances made to aerial surveys of macropods in New South Wales and Queensland. Regular aerial surveys of macropods across large areas of Australia's arid and semi‐arid rangelands were established as a response to concerns for the species' conservation. They became integral to the harvest management of the four macropod species – Eastern Grey Kangaroo (Macropus giganteus), Western Grey Kangaroo (M. fuliginosus), Red Kangaroo (Osphranter rufus) and Common Wallaroo (O. robustus). Harvest quotas are set as a proportion of population size, requiring absolute estimates of abundance. Counts were made in strip transects from fixed‐wing aircraft, but required correction for animals that are missed. In New South Wales and Queensland, counts are now made using line transect sampling, providing survey‐specific correction. Helicopters are used in more rugged and timbered areas and where Common Wallaroo can be more frequently found and harvested. Mark‐recapture distance sampling is used in more open country that can be surveyed using fixed‐wing aircraft and improves the accuracy of density estimates by accounting for animals missed on the transect line. Macropod populations are likely to be surveyed in the future by airborne imagery and by drones, but the technology needs further development. Spatial models could usefully provide small‐scale density estimates and address non‐random sampling. [ABSTRACT FROM AUTHOR]

Summary: Protecting native biodiversity is a difficult prospect in extremely modified landscapes, especially where high‐impact exotic species are widespread. Using new data and a review of the literature, this paper comments on the use of livestock grazing to manage the invasive and highly combustible pasture grass species, Buffel Grass (Cenchrus ciliaris) and thereby help conserve fire‐sensitive Brigalow (Acacia harpophylla) vegetation in reserves in Queensland, Australia. We cite evidence that shows that grazing is a potentially useful management tool in such cases and its use can be compatible with the protection of both fire‐sensitive vegetation and other native plant species within the understorey. However, there are limitations in implementing grazing within conservation reserves including the lack of a clear understanding of the influence of grazing on biodiversity and resource condition. Importantly, we highlight secondary invasion by the exotic grass Indian Couch (Bothriochloa pertusa) as a key emerging threat that may undermine the biodiversity benefits gained by grazing in reserves. Grazing can be a useful tool for conservation management in particular scenarios, but the associated risks demand accompanying monitoring and reporting of positive and negative impacts to ensure the fundamental aim of biodiversity protection is being achieved. [ABSTRACT FROM AUTHOR]