Interactions between European rabbits and native marsupials in the absence of terrestrial predators

Abstract

AbstractEuropean rabbits (Oryctolagus cuniculus) are ubiquitous across Australia and have the ability to influence native species directly and indirectly. Despite this, limited research focuses on interspecific interactions between rabbits and native mammals. We aimed to determine how site occupancy, detection probability, and temporal activity periods of native mammals changed in response to the presence or absence of rabbits. We monitored three native mammal species using 85 camera traps in a systematic grid at Mt Rothwell Conservation and Research Reserve (Victoria, Australia), a predator‐barrier fenced reserve with two distinct sections—an area with rabbits and an area without. Bettongs (rufous Aepyprymnus rufescens and eastern Bettongia gaimardi), eastern barred bandicoots (Perameles gunni), and southern brown bandicoots (Isoodon obesulus) had a naïve site occupancy of 71%, 42%, and 24%, respectively. Site occupancy for both bandicoot species decreased in areas with more clumping grass with eastern barred bandicoot occupancy increasing with leaf litter cover, and southern brown bandicoots with vegetation height. Rabbit presence did not influence site occupancy of any species. Species detection probabilities were generally positively associated with open vegetation and rabbit presence, except for southern brown bandicoots which were more detectable without rabbits. Both bandicoot species shifted their peak activity periods in the absence of rabbits having an earlier, and more defined activity peak. Our results demonstrate that the presence of rabbits in the absence of invasive predators may not influence the site occupancy of co‐occurring native mammals, however, could influence the behaviour of smaller co‐occurring mammals, either directly or indirectly.