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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]

Reintroductions of threatened species can fail due to a lack of site fidelity and dispersal of individuals away from the release site. Delayed‐release techniques are commonly used in reintroduction programmes to acclimatise animals to novel sites to improve site fidelity and survival following release. However, some studies have found negative or little effect of initial containment on post‐release outcomes, suggesting that the benefits of a delayed release may be species‐specific or dependent on the methods used. The western quoll (Dasyurus geoffroii) is a 900–1300 g carnivorous marsupial that has previously been found to travel long distances after release, potentially contributing to reintroduction failure. We investigated the effect of immediate versus delayed release on the survival, site fidelity and breeding success of western quolls reintroduced to the Ikara‐Flinders Ranges National Park in South Australia. Delayed‐release animals were confined to individual 10 × 10 m outdoor release pens and provided with supplementary food and water for ten days prior to release. Immediate‐release animals were released without any additional assistance provided. Monitoring of 39 radio‐collared quolls for three months after release failed to detect a difference in survival probability between release treatments. There was also no evidence to suggest that the success or timing of breeding differed between immediate‐ and delayed‐released quolls. However, a delayed release did significantly improve site fidelity. On average, delayed‐release quolls remained within a linear distance of 1.6 km (SE = 0.348, 95% CI = 0.98–2.39) of their release site over three months, compared to 3.26 km (SE = 0.36, 95% CI = 2.57–4.03) for immediate‐released animals. In unbounded release sites, delayed releases may assist with keeping western quolls within predator‐controlled release areas. Results from this study may be used to guide future reintroductions of this threatened species. [ABSTRACT FROM AUTHOR]

An important component of reintroduction is acclimatization to the release site. Movement parameters and breeding are common metrics used to infer the end of the acclimatization period, but the time taken to locate preferred food items is another important measure. We studied the diet of a reintroduced population of brushtail possums Trichosurus vulpecula in semi-arid South Australia over a 12 month period, investigating changes over time as well as the general diet. We used next-generation DNA sequencing to determine the contents of 253 scat samples, after creating a local plant reference library. Vegetation surveys were conducted monthly to account for availability. Dietary diversity and richness decreased significantly with time since release after availability was accounted for. We used Jacob's Index to assess selectivity; just 13.4% of available plant genera were significantly preferred overall, relative to availability. The mean proportion of preferred plant genera contained within individual samples increased significantly with time since release, but the frequency of occurrence of preferred plants did not. Five genera (Eucalyptus, Petalostylis, Maireana, Zygophyllum and Callitris) were present in more than half of samples. There was no difference in dietary preferences between sexes (Pianka overlap = 0.73). Our results suggest that acclimatization periods may be longer than those estimated via reproduction, changes in mass and movement parameters, but that under suitable conditions a changeable diet should not negatively affect reintroduction outcomes. Reintroduction projects should aim to extend post-release monitoring beyond the dietary acclimatization period and, for dry climates, diet should be monitored through a drought period. [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]

Sex determination of individuals is often required for ecological and behavioural studies but is difficult to carry out in the field for species that are only slightly dimorphic. To address this issue, researchers may use a variety of methods that rely solely on morphological measurements for sex determination. There are two main groups of morphological methods; (1) based on discriminant analysis, and (2) based on resolving mixed-modal distributions. Here, we use one method from each of the two groups to sex the slightly dimorphic New Holland Honeyeater, Phylidonyris novaehollandiae, in South Australia, and we compare results of the two methods in relation to a genetic standard. We found that performance of both methods was comparable, but varied between populations. We also found regional differences in the best discriminating variables for morphological sex determination. This regional variation in performance of methods indicates that a single method for morphological sex determination cannot be applied across regions, even within species; furthermore, average morphological trait values should be reviewed across years given the possible role of selection or drift to influence phenotype. We suggest that when accurate sex discrimination is important, an alternate, reliable method, such as anatomical or genetic identification, should be favoured above morphological methods. [ABSTRACT FROM AUTHOR]

Describes the habitats and feeding sites used by ten species of honeyeaters in the Mount Lofty Ranges near Adelaide, South Australia. Influence of beak shape and size on the feeding habits of the honeyeaters; Reasons behind the distribution of same-genus species in different habitats; Role of species habitat overlapping on the formation of a guild of species which are very similar in their overall ecology.

Discusses the disruption of bird-plant pollination systems in Southern Australia. Impact of vegetation clearance on bird-plant pollination systems; Bird-pollinated plants affected by the introduction of the European honeybee in the 1820s; Revegetation programs promoted; Implications for other bird-plant systems in other parts of Australia.