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Australia's arid shrublands have been impacted by a variety of threatening processes since European settlement, and changes to ecosystem structure and function have been observed at multiple levels. The lack of recruitment and regeneration of the perennial shrub and tree layer in these communities has implications for many shrubland birds, including species of conservation concern such as the Chestnut‐rumped Thornbill (Acanthiza uropygialis: Acanthizidae). We documented foraging behaviour and habitat selection of the Chestnut‐rumped Thornbill at the Arid Recovery Reserve in South Australia and surveyed vegetation characteristics within the Reserve and in an adjacent pastoral property. We found that Chestnut‐rumped Thornbills preferentially use certain plant species: Callitris glaucophylla, Acacia aneura, Acacia ligulata and Acacia tetragonophylla, and that these species were significantly less abundant at our study sites outside the Reserve than inside. Major differences in the structure and composition of the vegetation inside and outside the Reserve suggest that changes in habitat structure and composition occurring in the broader landscape (outside the fenced area) decrease the suitability of arid shrubland habitat for the Chestnut‐rumped Thornbill and may contribute to their absence in unprotected areas. Our study indicates that deterioration of the perennial shrub layer could have significant consequences for the persistence of the Chestnut‐rumped Thornbill in arid rangelands. Our findings highlight the importance of rangeland management and restoration of Australia's arid shrublands in preventing declines of the Chestnut‐rumped Thornbill and other insectivorous birds. [ABSTRACT FROM AUTHOR]

In South Australia, Swamps of the Fleurieu Peninsula are critically endangered due to past vegetation clearance and changes in hydrology, but still contain a high diversity of threatened plant species. This vegetation community provides habitat for 82 threatened ground‐stratum plant species, including the nationally critically endangered subshrub Hibbertia tenuis which is endemic to these swamps. With infrequent burning, native ferns and taller shrubs outcompete these species. We conducted glasshouse trials to determine the potential of fire to regenerate threatened and other swamp plant species. Soil samples from eight swamps were used in germination trials with half of each sample treated with heat plus smoke, and half left untreated. Samples were spread onto trays (n = 188), and seedling emergence was recorded for twelve months. Emergence was dominated by native species (2649 seedlings m−2) compared to exotics (675 seedlings m−2). In total, 48 native and 25 introduced species germinated, with 21% of germinated native species absent from the above‐ground vegetation. The dominant native fern Gleichenia microphylla did not emerge from any soil samples, indicating that recovery likely lags behind that of ground‐strata species, giving them time to establish and set seed before being outcompeted. Thirty‐four rare or threatened species germinated, including five species absent from above‐ground vegetation. Of all native species that emerged, only five were confined to heat plus smoke treatments, suggesting most species will regenerate without fire if overstorey competition is reduced. However, seedling emergence of native shrubs/subshrubs more than doubled with the fire treatment. Of particular importance, H. tenuis showed an 18‐fold increase in germination when treated with heat plus smoke. This study supports the utility of ecological burns as a management tool to regenerate threatened plant species in long‐undisturbed peaty heathlands on permanent swamps. [ABSTRACT FROM AUTHOR]

When native herbivores are enclosed in fenced reserves without predators or dispersal options then overgrazing can occur, leading to damage to vegetation and co‐occurring fauna species. One‐way gates that allow medium‐sized herbivores to exit fenced reserves may be an effective management tool to address overabundance or facilitate population expansion. We tested the use of one‐way gates to facilitate the movement of the reintroduced burrowing bettong (Bettongia lesueur) from inside to outside a fenced reserve in arid South Australia. One‐way gates were installed in the exterior fence of the reserve and assessed using remote motion‐sensor cameras. The influence of gate position (dune, swale or corner) and provision of food were assessed in relation to gate visits and exits. Animals were trapped inside and outside the gates to determine any population bias in gate exits. Baited gates recorded significantly more exits than unbaited gates and dune gates had higher exit rates than interdunal swale gates. When gates were unbaited, those installed in corners of the reserve showed significantly higher visitation by bettongs and a non‐significant trend towards more exits compared to gates placed in straight sections of fence along dunes or swales. There was no sex or age bias of burrowing bettongs using the gates and bettongs travelled between 75 m and 1535 m from their warrens to use the gates. No non‐target species gained access to the reserve through the one‐way gates and only two non‐target animals used the gates to exit the reserve confirming gate specificity for bettongs. During the same period, 96 burrowing bettongs exited the reserve through the one‐way gates. One‐way gates may be a management strategy for facilitating passive movement of medium‐sized herbivores outside of fenced reserves for the purposes of reducing overpopulation or facilitating population expansion outside reserves. [ABSTRACT FROM AUTHOR]