Seasonal variation in the faecal microbiome and diet of yellow-footed rock-wallabies (Petrogale xanthopus xanthopus) in two different habitat types in South Australia

The importance of the faecal microbiome for the conservation of threatened species is becoming recognised as an influential factor, especially in the face of climate change induced environmental disturbances. The yellow-footed rock-wallaby (YFRW; Petrogale xanthopus xanthopus) is a marsupial macropodid endemic to the semi-arid regions of South Australia, New South Wales and Queensland, and is currently classified as Vulnerable (EPBC Classification). This study aimed to determine current faecal microbial diversity and its association with diet within two South Australian YFRW populations. DNA sequencing targeting the 16S rRNA gene revealed that location was the greatest driver of faecal microbial richness, evenness and composition (P < 0.01), with season and the interaction of location x season also statistically significant (P < 0.01). The main phyla identified throughout were the Firmicutes and Bacteroidota, representing over 80% of total ASV diversity. Diet varied between individuals throughout, but each study site showed a preference for Acacia species at opposing times of the year. There appeared to be a slight increase in the proportion of Firmicutes during the times when Acacia was consumed at a high proportion, although a greater sample size is needed to support or refute this. Further research and continued monitoring is required to understand the function of these microbes, and specifically for microbes which allow the animal to persist within the semi-arid region of Australia; a region thought to be heavily impacted by climate change.