Assessing the impact of the black summer fires on Kangaroo Island threatened invertebrates: towards rapid habitat assessments for informing targeted post-fire surveys

Abstract

The black summer fires of 2019–2020 burnt almost half of Kangaroo Island (KI), impacting large areas of high-quality native vegetation supporting many rare, endemic and/or undescribed invertebrate species. In the aftermath there was a need to survey for a range of species with few prior records and variable amounts of biological information. Therefore, a project was undertaken to perform Rapid Habitat Assessments (RHAs) for 13 priority KI invertebrate species, followed by species-specific surveys. RHAs are a method employed to quickly assess the presence/absence of key habitat features required by various taxa at a given site. Here, we used RHAs to assess the habitat of the 13 priority KI species and to prioritise a number of sites for species-specific surveys. Published data, expert knowledge and our own experience with the taxa, were used to define habitat features important to each taxon to target survey effort. Eight of the 13 priority taxa were located during surveys, within the burn scar or adjacent intact vegetation, revealing range extensions for five species. Species varied in susceptibility to fire and there is significant concern regarding the conservation status of limited-range KI endemics Moggridgea rainbowi KI micro-trapdoor spider, Zephyrarchaea austini KI assassin spider, and Psacadonotus insulanus KI robust fan-winged katydid. Given predictions of increasing climatic volatility, there is a need for methods to assess multiple species with differing life histories and limited associated data that quickly and accurately prioritise habitats for surveys.