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Mycophagous bioturbators provide ecosystem services that can be important for the resilience and restoration of ecosystems. Among the Australian mammals, mycophagy is most prevalent within the Potoroidae (bettongs and potoroos). However, proportionally more species of Potoroidae are either recently extinct or currently threatened than any other mammalian family in Australia, and they are among the least studied. The critically endangered woylie, or brush-tailed bettong ( Bettongia penicillata ), is a mycophagous, ground dwelling ‘ecosystem engineer’ that was one of Australia’s most abundant and widely distributed potoroids prior to European settlement. After substantial range contraction, however, the remaining indigenous populations are now restricted to eucalypt forests in south-western Australia. Using an experimental approach, we investigated the population responses of the woylie to timber harvesting in these forests. Nine treatments, including varying logging intensities and unharvested controls, were applied at 22 sites. The abundance of the woylie in the harvested areas, in unharvested stands between logged areas, and in extensive unharvested stands outside the harvest management area were compared using a replicated before-after-control-impact (BACI) repeated measures design and capture-mark-recapture modelling. A total of 5860 captures of 815 individuals were recorded during 35 trapping sessions over 16 years (one year preceding, two years during, and 13 years after disturbance). Capture rate was a good index of abundance for this species and woylie abundance, survivorship and recruitment were not adversely affected by silvicultural practices in the jarrah ( Eucalyptus marginata ) forest. On the contrary, the harvested areas may have afforded some localised protection when an unrelated, species-wide decline began three years after harvesting disturbance ended; woylie numbers declined by up to 77% and 95% in harvested and unharvested areas, respectively. Thus the nature and spatial extent of the timber harvesting regimes investigated in this study were not a major threatening process for this species. However, ongoing monitoring and evaluation are necessary to ensure that timber harvesting activities remain benign in the face of a changing climate, possible increased mortality from introduced predators, disease, and further declines in the abundance of this critically endangered marsupial. [ABSTRACT FROM AUTHOR]

Populations of threatened animals are increasingly preserved within predator-free havens, where populations tend to grow rapidly, resource competition increases, and traits relevant to avoiding predation may be selected against. We examine this phenomenon using a ten-year longitudinal dataset on a threatened Australian mammal; the woylie (Bettongia penicillata ogilbyi). Behavioural and morphological data were collected during routine monitoring of a havened woylie population and an adjacent wild population where predators occur, from which six traits relating to predator escape were extracted. Paired comparisons revealed that havened woylies were less likely to show injuries from excessive agitation in traps, were less likely to eject pouch young, and had shorter approach distances compared to woylies outside the haven, suggesting a dampened antipredator response. Further, body mass and relative leg length declined over time in the havened population, compared with no change outside of the haven, suggesting selection in the haven against body size. Population density affected body size and agitation in traps differently in havened and non-havened populations, indicating an interaction between resource competition and relaxed selection that likely hastens the loss of anti-predator traits. Our study offers a mechanistic understanding of the loss of anti-predator responses in havens, which is essential for guiding how populations could be managed to better realise their potential for recovering threatened fauna. [ABSTRACT FROM AUTHOR]