One year on: rapid assessment of fauna and red fox diet after the 2019–20 mega-fires in the Blue Mountains, New South Wales

Abstract

Australia’s 2019–20 mega-fires burnt 79% of the Greater Blue Mountains World Heritage Area, prompting an urgent need for rapid on-ground post-fire assessments of flora and fauna to aid in post-fire recovery. This project aimed to determine spatial patterns in populations and assemblages of vertebrates, vertebrate temporal activity, and the diet of the invasive Red Fox Vulpes vulpes, across burnt and unburnt sites. Using remote camera traps we surveyed 12 unburnt and 10 burnt sites approximately 12 months after the fires. We detected 41 species (11 mammals, 28 birds and 2 reptiles), with different species composition, but similar vertebrate species richness across both unburnt and burnt sites. The relative abundance of the Eastern Grey Kangaroo Macropus giganteus, Common Wombat Vombatus ursinus and Australian Magpie Gymnorhina tibicen was higher in burnt sites, while small mammals (< 500 g) had higher relative abundance at unburnt sites. There was no difference in the relative abundance of the Superb Lyrebird Menura novaehollandiae across burnt and unburnt sites, and although 11 species of bird were only detected at unburnt sites, the numbers were too low for reliable estimates of differences. Red Fox scat analysis (n=23) revealed that invertebrates and plant material were the dominant prey items in both burnt and unburnt sites, but medium-sized mammals increased in Red Fox diets in burnt sites, and reptiles were consumed disproportionately more by Red Foxes in burnt compared to unburnt sites. Although the short-term nature of this study and low scat sample size limited detailed insights, our rapid survey was an effective tool to gain preliminary data on species responses to the 2019–20 megafires in the Blue Mountains and contribute to a baseline for understanding species recovery.