Using eDNA metabarcoding to understand the effect of fire on the diet of small mammals in a woodland ecosystem

Abstract

Food acquisition is a fundamental process that drives animal distribution and abundance, influencing how species respond to changing environments. Disturbances such as fire create significant shifts in available dietary resources, yet, for many species, we lack basic information about what they eat, let alone how they respond to a changing resource base. In order to create effective management strategies, faunal conservation in flammable landscapes requires a greater understanding of what animals eat and how this change following a fire. What animals eat in postfire environments has received little attention due to the time-consuming methodologies and low-resolution identification of food taxa. Recently, molecular techniques have been developed to identify food DNA in scats, making it possible to identify animal diets with enhanced resolution. The primary aim of this study was to utilize eDNA metabarcoding to obtain an improved understanding of the diet of three native Australian small mammal species: yellow-footed antechinus (Antechinus flavipes), heath mouse (Pseudomys shortridgei), and bush rat (Rattus fuscipes). Specifically, we sought to understand the difference in the overall diet of the three species and how diet changed over time after fire. Yellow-footed antechinus diets mostly consisted of moths, and plants belonging to myrtles and legume families while bush rats consumed legumes, myrtles, rushes, and beetles. Heath mouse diet was dominated by rushes. All three species shifted their diets over time after fire, with most pronounced shifts in the bush rats and least for heath mice. Identifying critical food resources for native animals will allow conservation managers to consider the effect of fire management actions on these resources and help conserve the species that use them.

An experimental design for obtaining DNA of a target species and its diet from a single non‐invasive genetic protocol

“…This has led to molecular scatology studies that have focused on the diet of target wildlife species (e.g. Anderson et al., 2018 ; Berman & Inbar, 2022 ; Henger et al., 2022 ; Jorns et al., 2020 ; Khalatbari et al., 2022 ; King & Schoenecker, 2019 ; Klure et al., 2022 ; McLennan et al., 2022 ; Mitchell et al., 2022 ; Nelms et al., 2019 ; O'Rourke et al., 2021 ; Roffler et al., 2021 ; Wanniarachchi et al., 2022 ). In parallel, other molecular scatology studies continue to focus on the behaviour, gene flow and space‐use patterns of the target species itself (e.g.…”

The role of grass-tree Xanthorrhoea semiplana (Asphodelaceae) canopies in temperature regulation and waterproofing for ground-dwelling wildlife

“…A large amount of evidence highlights their use as food (e.g. Wanniarachchi et al 2022 for some small mammal species) and shelter by many invertebrate and vertebrate species. In a review with a focus on two Queensland species, Borsboom (2005) determined that this evidence concerned over 315 invertebrate species and nearly 100 vertebrate species.…”