Rapid change in anti‐predator behaviour of a threatened marsupial after thousands of years of isolation from predators

Abstract

AbstractPrey naivety occurs when an animal does not recognize or is unable to respond effectively to the threat of a predator. Many animals lose their anti‐predator responses if they become isolated from predators, becoming vulnerable to increased predation rates if released into areas where native or introduced predators are present. In situ exposure to introduced predators is a technique that has been shown to improve anti‐predator traits in burrowing bettongs (Bettongia lesueur) and greater bilbies (Macrotis lagotis) and is associated with greater survival in bilbies. However, little is known about how in situ exposure to native predators can address the issue of prey naivety. This study investigated whether Shark Bay bandicoots (Perameles bougainville) from a remnant island population isolated from all mammalian predators for several thousand years could improve their anti‐predator behaviour after living with a native predator, the western quoll (Dasyurus geoffroii). We compared the vigilance and wariness behaviour, and nest site attributes of bandicoot populations living with and without native quolls at the Arid Recovery Reserve in South Australia. We found that after 6 years of quoll exposure, quoll‐exposed bandicoots had significantly larger flight initiation distances and spent more time engaged in vigilance behaviours at feed trays compared to control bandicoots. Quoll‐exposed bandicoots also selected nests with increased vegetation cover, preferring nests with both understory and overstory shrub cover present. The results of this study indicate that in situ exposure to native predators can improve vigilance and wariness behaviours in Shark Bay bandicoots over relatively short time frames. Exposing threatened species to native predators may assist with preparing them for life outside fenced safe havens.