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Establishing methods that allow for more focused management of wildlife under predator pressure may increase the efficiency of managing problematic predators. Non‐invasive dietary analysis and identification of conservation‐sensitive prey in the diet of 'culprit' predator individuals could help to facilitate this and is worthy of exploration. Recently on Phillip Island, Australia, Little Ravens Corvus mellori have emerged as a prominent predator on the clutches of burrow‐nesting Little Penguins Eudyptula minor. We tested the feasibility of using non‐invasive PCR approaches targeting the penguin mitochondrial 16S rRNA marker gene to establish whether penguin DNA could be detected in raven faecal samples, potentially enabling the identification of culprit ravens missed by extensive field observation. Using a metabarcoding approach, we examined the feasibility of non‐invasively establishing other dietary items via high‐throughput amplicon sequencing. We documented components of raven diet using the universal mitochondrial 16S rRNA, insect‐specific 'Chiar' 16S rRNA and plant ITS2. The assemblage of dietary items did not differ with raven culprit status (i.e. a raven previously observed preying upon penguin), sex or date. Penguin was detected in the diet of some individuals classified observationally as non‐culprits. Although some cases may conceivably have been false detections, other explanations include missed depredation events, consumption via scavenging or through secondary consumption (e.g. eating invertebrates that have consumed penguin). While this study found metabarcoding unreliable for unambiguous assigning of raven culprit status, at least as we implemented it, it may hold promise complementing observations if consumption via scavenging can be distinguished from direct depredation. [ABSTRACT FROM AUTHOR]

The article discusses the absence of the high-pathogenicity avian influenza (HPAI) H5N1 lineage 2.3.4.4b in Australia for the second consecutive year. The HPAI H5N1 has had a significant impact on the poultry industry and wildlife globally. While wild birds, particularly waterfowl, were initially thought to be responsible for the spread of HPAI, recent viral incursions suggest that seabirds are also involved. The absence of HPAI in Australia may be attributed to the absence of waterfowl species that migrate to the region and potential cross-protection from ancestral HPAI lineages in Asia. Continued surveillance is necessary to detect and respond to any potential incursions in the future. [Extracted from the article]

A native Australian corvid, Little Raven Corvus mellori, has emerged as a dominant and problematic predator of an ecologically and economically important seabird, the Little Penguin Eudyptula minor. In 2013, ravens successfully preyed upon clutches/broods of the burrow-nesting penguin, especially those in shallower, more accessible burrows. Individual raven size might mediate which ravens attack penguins; smaller ravens may be able to enter burrows more easily; alternatively, larger ravens may be more capable of overcoming penguin parental defence. Here, we consider the predator-prey interactions to assess whether associations with burrow characteristics persisted and examine whether raven size mediated propensity to prey upon penguin eggs. We compared data from the 2013 and 2015 penguin breeding seasons at Phillip Island (Victoria, Australia) for differences in clutch survival and burrow characteristics. We also examined raven morphometrics to determine if any physical differences existed between known burrow-predators (“culprits”) and other birds. During the 2013 breeding season, penguins suffered clutch losses of 61.1% compared with 33.9% in 2015. Burrow characteristics changed between seasons—most noticeably, burrows were deeper in 2015 and ravens no longer discriminated between burrow characteristics. Culprits were heavier and larger. While we could not eliminate inter-annual variability as a possible contributing factor, our results were consistent with rapid adaptation of prey and predator to intense emergent depredation. Penguins may now construct deeper burrows, and ravens evidently no longer select more vulnerable burrows. Larger ravens may be more capable of approaching and attacking penguin burrows. [ABSTRACT FROM AUTHOR]

If conservation depends on people, then community partnerships are the lynchpin to conservation success. The contribution of local knowledge, intellectual capital and volunteer labour not only saves project managers invaluable time and money, it fosters ownership and longevity into conservation initiatives well beyond their projected timeframe. Island communities are socially and culturally diverse and driven by a range of motivations. Hence, if we are to deliver conservation programs at scale, we need to better understand and embed these drivers into program design. We present four contemporary case studies on major populated islands in Australia where community collaborations are building the collective impact needed to underpin conservation success. They contain key learnings about community involvement, to help guide managers with future island planning and avoid some pitfalls. Conservation depends on people and community partnerships not only save time and money, but they also foster ownership and longevity of conservation initiatives well beyond their project timeframe. To engage island communities successfully in conservation efforts, we need to understand their motivations and embed these into program design. We present four case studies on major populated islands in Australia where community collaboration is building the collective impact needed for conservation success. They contain key learnings to help guide managers in future island planning. [ABSTRACT FROM AUTHOR]

Beta-phase gallium oxide (β -Ga2O3) is a promising semiconductor for high frequency, high temperature, and high voltage applications. In addition to the β -phase, numerous other polymorphs exist and understanding the competition between phases is critical to control practical devices. The phase formation sequence of Ga2O3, starting from amorphous thin films, was determined using lateral-gradient laser spike annealing at peak temperatures of 500–1400 °C on 400 μs to 10 ms timescales, with transformations characterized by optical microscopy, x-ray diffraction, and transmission electron microscopy (TEM). The resulting phase processing map showed the γ -phase, a defect-spinel structure, first nucleating under all annealing times for temperatures from 650 to 800 °C. The cross-sectional TEM at the onset of the γ -phase formation showed nucleation near the film center with no evidence of heterogeneous nucleation at the interfaces. For temperatures above 850 °C, the thermodynamically stable β -phase was observed. For anneals of 1–4 ms and temperatures below 1200 °C, small randomly oriented grains were observed. Large grains were observed for anneals below 1 ms and above 1200 °C, with anneals above 4 ms and 1200 °C resulting in textured films. The formation of the γ -phase prior to β -phase, coupled with the observed grain structure, suggests that the γ -phase is kinetically preferred during thermal annealing of amorphous films, with β -phase subsequently forming by nucleation at higher temperatures. The low surface energy of the γ -phase implied by these results suggests an explanation for the widely observed γ -phase inclusions in β -phase Ga2O3 films grown by a variety of synthesis methods. [ABSTRACT FROM AUTHOR]

Globally, predator aversion training has assisted naive prey species to learn to evade introduced predators, improving translocation success. Eastern barred bandicoots (Perameles gunnii ; hereafter 'bandicoot') are extinct on mainland Australia due to habitat loss and introduced predators, and are the focus of a long-term captive breeding and reintroduction program. Our trials showed that captive bandicoots failed to recognise cat (Felis catus) scents as belonging to a predator, suggesting prey naivety towards cats. We trialled five stimuli to elicit short-term fear behaviour in bandicoots. An automatic compressed air spray and automatic bin lid were most effective. We coupled these stimuli with cat urine during predator aversion training and presented them to bandicoots on three occasions. Bandicoots learnt to avoid the area containing cat urine, suggesting bandicoots are capable of learning new behaviours rapidly. Six trained and five untrained captive bandicoots where released onto Summerland Peninsular, Phillip Island (with cat densities at 1.1 cats/km2). Both had high survival and recapture rates 7 months after release. Training endangered species to avoid introduced predators could assist with long-term species recovery. Prey naivety to introduced predators can cause threatened species translocations to fail. Before a release to Summerland Peninsula, Phillip Island, Victoria, captive eastern barred bandicoots (Perameles gunnii) successfully underwent rapid predator aversion training to improve vigilance in the presence of feral cats (Felis catus). Following release, trained and untrained bandicoots had high survival rates. Our study demonstrates that bandicoots can learn predator avoidance behaviours quickly and are suitable for future training. We suggest translocation success of other endangered species could be improved by predator avoidance training. [ABSTRACT FROM AUTHOR]

Roads can have significant impacts on wildlife populations by impeding movement, restricting access to resources and causing wildlife-vehicle collisions. In particular, wildlife-vehicle collisions represent a substantial conservation and social problem, and although mitigation measures are available, an increased understanding of the temporal and spatial patterns of animal movement around roads will enhance their effectiveness. We analysed GPS telemetry data from 47 swamp wallabies Wallabia bicolor on Phillip Island, south-east Australia, within patches of native vegetation dissected by roads. Our aims were to determine if (a) road crossing frequency was influenced by time period (day, night) or sex, (b) wallabies avoided roads, and if avoidance was influenced by time period or sex and (c) road crossing locations were associated with dense vegetation, and other habitat characteristics. We found that males crossed roads more often at night than during the day while females showed the opposite pattern. Further, wallabies avoided roads, with some evidence that avoidance increased at night (p = 0.07). The chance of a wallaby crossing roads with high speed limits (80-100 km h-1) increased with vegetation density during the day but not at night. In contrast, vegetation density had no influence on crossing locations along roads with lower (50-70 km h-1) speed limits during the day or night. Both vegetation density and vehicle speed may influence wallaby-vehicle collisions and suggest management strategies targeting these factors. Partial fencing guiding wallabies towards safer crossing locations, combined with other measures such as reduced speed limits and signage, could reduce collisions between vehicles and swamp wallabies on Phillip Island. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is considered a disease risk for many native Australian species. Feral cats are the key definitive host of T. gondii in Australia and therefore, investigating the epidemiology of T. gondii in cat populations is essential to understanding the risk posed to wildlife. Test sensitivity and specificity are poorly defined for diagnostic tests targeting T. gondii in cats and there is a need for validated techniques. This study focused on the feral cat population on Phillip Island, Victoria, Australia. We compared a novel real-time PCR (qPCR) protocol to the modified agglutination test (MAT) and used a Bayesian latent class modelling approach to assess the diagnostic parameters of each assay and estimate the true prevalence of T. gondii in feral cats. In addition, we performed multivariable logistic regression to determine risk factors associated with T. gondii infection in cats. Overall T. gondii prevalence by qPCR and MAT was 79.5% (95% confidence interval 72.6–85.0) and 91.8% (84.6–95.8), respectively. Bayesian modelling estimated the sensitivity and specificity of the MAT as 96.2% (95% credible interval 91.8–98.8) and 82.1% (64.9–93.6), and qPCR as 90.1% (83.6–95.5) and 96.0% (82.1–99.8), respectively. True prevalence of T. gondii infection in feral cats on Phillip Island was estimated as 90.3% (83.2–95.1). Multivariable logistic regression analysis indicated that T. gondii infection was positively associated with weight and this effect was modified by season. Cats trapped in winter had a high probability of infection, regardless of weight. The present study suggests qPCR applied to tissue is a highly sensitive, specific and logistically feasible tool for T. gondii testing in feral cat populations. Additionally, T. gondii infection is highly prevalent in feral cats on Phillip Island, which may have significant impacts on endemic and introduced marsupial populations. Image 1 • Extremely high prevalence of T. gondii infection in feral cats on Phillip Island. • Cats trapped in winter had a high probability of being infected with T. gondii. • Sensitivity and specificity of the MAT in cats estimated at 96.2% and 82.1%. • Sensitivity and specificity of T. gondii qPCR in cats estimated at 90.1% and 96.0%. [ABSTRACT FROM AUTHOR]

Digging mammals are often considered ecosystem engineers, as they affect important properties of soils and in turn nutrient exchange, vegetation dynamics and habitat quality. Returning such species, and their functions, to areas from where they have been extirpated could help restore degraded landscapes and is increasingly being trialled as a conservation tool. Studies examining the effects of digging mammals have largely been from arid and semi‐arid environments, with little known about their impacts and importance in mesic systems. To address this knowledge gap, we investigated the ecological role of a recently introduced population of eastern barred bandicoots (Perameles gunnii) on Churchill Island, Victoria, south‐eastern Australia, from which all digging mammals have been lost. We quantified the annual rate of soil turnover by estimating the number of foraging pits bandicoots created in 100‐m2 plots over a 24‐h period. Foraging pit counts could not be completed in each season, and the overall turnover estimate assumes that autumn/winter months represent turnover rates for the entire year; however, this is likely to fluctuate between seasons. Ten fresh and ten old pits were compared to paired undug control sites to quantify the effect soil disturbance had on soil hydrophobicity, moisture content and soil strength. Plots contained between zero and 64 new foraging pits each day. We estimated that an individual eastern barred bandicoot digs ~487 (95% CI = 416–526) small foraging pits per night, displacing ~13.15 kg (95% CI = 11.2–14.2 kg) of soil, equating to ~400 kg (95% CI = 341–431 kg) of soil in a winter month. Foraging pits were associated with decreased soil compaction and increased soil moisture along the foraging pit profile. Eastern barred bandicoots likely play an important role in ecosystems through their effects on soil, which adds to an increasing body of knowledge suggesting restoration of ecosystems, via the return of ecosystem engineers and their functions, holds much promise for conserving biodiversity and ecological function. [ABSTRACT FROM AUTHOR]

Animals access resources such as food and shelter, and acquiring these resources has varying risks and benefits, depending on the suitability of the landscape. Some animals change their patterns of resource selection in space and time to optimize the trade‐off between risks and benefits. We examine the circadian variation in resource selection of swamp wallabies (Wallabia bicolor) within a human‐modified landscape, an environment of varying suitability. We used GPS data from 48 swamp wallabies to compare the use of landscape features such as woodland and scrub, housing estates, farmland, coastal areas, wetlands, waterbodies, and roads to their availability using generalized linear mixed models. We investigated which features were selected by wallabies and determined whether the distance to different landscape features changed, depending on the time of the day. During the day, wallabies were more likely to be found within or near natural landscape features such as woodlands and scrub, wetlands, and coastal vegetation, while avoiding landscape features that may be perceived as more risky (roads, housing, waterbodies, and farmland), but those features were selected more at night. Finally, we mapped our results to predict habitat suitability for swamp wallabies in human‐modified landscapes. We showed that wallabies living in a human‐modified landscape selected different landscape features during day or night. Changing circadian patterns of resource selection might enhance the persistence of species in landscapes where resources are fragmented and disturbed. [ABSTRACT FROM AUTHOR]

Effective ecosystem-based management requires estimates of abundance and population trends of species of interest. Trend analyses are often limited due to sparse or short-term abundance estimates for populations that can be logistically difficult to monitor over time. Therefore it is critical to assess regularly the quality of the metrics in long-term monitoring programs. For a monitoring program to provide meaningful data and remain relevant, it needs to incorporate technological improvements and the changing requirements of stakeholders, while maintaining the integrity of the data. In this paper we critically examine the monitoring program for the Australian fur seal (AFS) Arctocephalus pusillus doriferus as an example of an ad-hoc monitoring program that was co-ordinated across multiple stakeholders as a range-wide census of live pups in the Austral summers of 2002, 2007 and 2013. This 5-yearly census, combined with historic counts at individual sites, successfully tracked increasing population trends as signs of population recovery up to 2007. The 2013 census identified the first reduction in AFS pup numbers (14,248 live pups, -4.2% change per annum since 2007), however we have limited information to understand this change. We analyse the trends at breeding colonies and perform a power analysis to critically examine the reliability of those trends. We then assess the gaps in the monitoring program and discuss how we may transition this surveillance style program to an adaptive monitoring program than can evolve over time and achieve its goals. The census results are used for ecosystem-based modelling for fisheries management and emergency response planning. The ultimate goal for this program is to obtain the data we need with minimal cost, effort and impact on the fur seals. In conclusion we identify the importance of power analyses for interpreting trends, the value of regularly assessing long-term monitoring programs and proper design so that adaptive monitoring principles can be applied. [ABSTRACT FROM AUTHOR]

The availability of low-cost wildlife trackers increases the capacity to collect valuable ecological data when research budgets are limited. We converted a commercially available global positioning system (GPS) product into a low-cost tracking device that sends data via the mobile phone network, and assessed its performance under varying conditions. We established a stationary test, deploying devices along a continuum from open urban areas to topographically and structurally complex forested sites. We tested three features of the device: (a) the GPS, by measuring fix success rate, fix precision and horizontal dilution of precision (HDOP), (b) remote download capacity via the mobile phone network and (c) battery drain. Measures of GPS performance demonstrated high fix success rates and precision. HDOP values were influenced by habitat type and topographical position, but generally remained very low, giving an acceptable degree of error for most applications in wildlife research. Devices experienced delayed data transmission at sites with less phone reception, and faster battery drain at sites with denser vegetation. We recorded device malfunctions in 8.2% of the 110 sampling locations, but these were not associated with habitat type or topography. Our device was effective under a wide range of conditions, and the development process we used provides guidance to other researchers aiming to develop cost-effective wildlife trackers. Reducing the financial and labour costs of acquiring high-quality movement data will improve the capacity to increase sample size in animal movement studies. [ABSTRACT FROM AUTHOR]

Egg predation is a major cause of reproductive failure among birds, and can compromise the viability of affected populations. Some egg predators aggregate near colonially breeding birds to exploit the seasonal increase of prey resources. We investigated spatial and temporal variations in the abundance of an egg predator (little raven C orvus mellori; Corvidae) to identify whether ravens aggregate spatially or temporally to coincide with any of three potential prey species: burrow-nesting little penguin ( E udyptula minor; Spheniscidae), short-tailed shearwater ( A rdenna tenuirostris; Procellariidae), and surface-nesting silver gull ( C hroicocephalus novaehollandiae; Laridae). We derived spatially explicit density estimates of little ravens using distance sampling along line transects throughout a calendar year, which encompassed little penguin, short-tailed shearwater and silver gull breeding and non-breeding seasons. High raven abundance coincided temporally with penguin and gull egg laying periods but not with that of shearwaters. The spatial distribution of raven density corresponded with the little penguin colony but not with shearwater or gull colonies. Thus, the presence of little penguin eggs in burrows correlated strongly with little raven activity, and this implies that little ravens may have learnt to exploit the plentiful subsurface food resource of little penguin eggs. Corvid management may be required to maintain the viability of this socially and economically important penguin colony. [ABSTRACT FROM AUTHOR]

Methods of calculating wildlife entanglement rates are not standardised between studies and often ignore the influence of observer effort, confounding comparisons. From 1997–2013 we identified 359 entangled Australian fur seals at Seal Rocks, south-eastern Australia. Most entanglement materials originated from commercial fisheries; most frequently entangling pups and juveniles. Using Generalized Additive Mixed Models, which incorporated observer effort and survey frequency, we identified that entanglements were observed more frequently amongst pups from July to October as they approached weaning. Neither the decline in regional fishing intensity nor changing seal population size influenced the incidence of entanglements. Using the models, we estimated that 302 (95% CI = 182–510) entangled seals were at Seal Rocks each year, equivalent to 1.0% (CI = 0.6–1.7%) of the site population. This study highlights the influence of observer effort and the value of long-term datasets for determining the drivers of marine debris entanglements. [ABSTRACT FROM AUTHOR]

Context. Egg depredation is a major cause of reproductive failure among birds and can drive population declines. In this study we investigate predatory behaviour of a corvid (little raven; Corvus mellori) that has only recently emerged, leading to widespread and intense depredation of eggs of a burrow-nesting seabird (little penguin; Eudyptula minor). Aims. The main objective of this study was to measure the rate of penguin egg depredation by ravens to determine potential threat severity. We also examined whether penguin burrow characteristics were associated with the risk of egg depredation. Ravens generally employ two modes of predatory behaviour when attacking penguin nests; thus we examined whether burrow characteristics were associated with these modes of attack. Methods. Remote-sensing cameras were deployed on penguin burrows to determine egg predation rates. Burrow measurements, including burrow entrance and tunnel characteristics, were measured at the time of camera deployment. Key results. Overall, clutches in 61% of monitored burrows (n = 203) were depredated by ravens, the only predator detected by camera traps. Analysis of burrow characteristics revealed two distinct types of burrows, only one of which was associated with egg depredation by ravens. Clutches depredated by ravens had burrows with wider and higher entrances, thinner soil or vegetation layer above the egg chamber, shorter and curved tunnels and greater areas of bare ground and whitewash near entrances. In addition, 86% were covered by bower spinach (Tetragonia implexicoma), through which ravens could excavate. Ravens used two modes to access the eggs: they attacked through the entrance (25% of burrow attacks, n = 124); or dug a hole through the burrow roof (75% of attacks, n = 124). Burrows that were subject to attack through the entrance had significantly shorter tunnels than burrows accessed through the roof. Conclusions. The high rates of clutch loss recorded here highlight the need for population viability analysis of penguins to assess the effect of egg predation on population growth rates. Implications. The subterranean foraging niche of a corvid described here may have implications for burrow-nesting species worldwide because many corvid populations are increasing, and they exhibit great capacity to adopt new foraging strategies to exploit novel prey. [ABSTRACT FROM AUTHOR]

(SnSe)1.2TiSe2 was found to self-assemble from a precursor containing modulated layers of Sn-Se and Ti-Se over a surprisingly large range of layer thicknesses and compositions. The constituent lattices form an alternating layer superstructure with rotational disorder present between the layers. This compound was found to have the highest Seebeck coefficient measured for analogous TiX2 containing misfit layered compounds to date, suggesting potential for low-temperature thermoelectric applications. Electrical characterization suggests that electrons transferred from SnSe to TiSe2 are responsible for the higher carrier concentration observed relative to bulk TiSe2. The transfer of charge from one constituent to the other may provide a mechanism for doping layered dichalcogenides for various applications without negatively affecting carrier mobility. [ABSTRACT FROM AUTHOR]

Context. Predator-control aims to reduce an impact on prey species, but efficacy of long-term control is rarely assessed and the reductions achieved are rarely quantified. Aims. We evaluated the changing efficacy of a 58-year-long campaign against red foxes (Vulpes vulpes) on Phillip Island, a 100-km[sup 2] inhabited island connected to the Australian mainland via a bridge. The campaign aimed to eliminate the impact of foxes on ground-nesting birds, particularly little penguins (Eudyptula minor). Methods. We monitored the success rate of each fox-control technique employed, the level of effort invested if available, demographics of killed foxes, the numbers of penguins killed by foxes and penguin population size. Key results. The campaign began as a bounty system that ran for 30 years and was ineffective. It transitioned into a coordinated, although localised, control program from 1980 to 2005 that invested considerable effort, but relied on subjective assessments of success. Early during the control period, baiting was abandoned for less effective methods that were thought to pose fewer risks, were more enjoyable and produced carcasses, a tangible result. Control was aided by a high level of public awareness, by restricted fox immigration, and by a clear, achievable and measurable target, namely, to prevent little penguin predation by foxes. Carcasses did prove valuable for research, revealing the genetic structure and shifts in fox demographics. The failure of the program was evident after scientific evaluation of fox population size and ongoing fox impacts. In 2006, the campaign evolved into an eradication attempt, adopting regular island-wide baiting, and since then, has achieved effective knock-down of foxes and negligible predation on penguins. Conclusions. Effective predator control was achieved only after employing a dedicated team and implementing broad-scale baiting. Abandoning widespread baiting potentially delayed effective control for 25 years. Furthermore, both predator and prey populations should be monitored concurrently because the relationship between predator abundance and impact on prey species is not necessarily density dependent. Implications. Critical to adopting the best management strategy is evaluating the efficacy of different methods independently of personal and public biases and having personnel dedicated solely to the task. [ABSTRACT FROM AUTHOR]

Invasive rodent species have established on 80% of the world's islands causing significant damage to island environments. Insular ecosystems support proportionally more biodiversity than comparative mainland areas, highlighting them as critical for global biodiversity conservation. Few techniques currently exist to adequately detect, with high confidence, species that are trap-adverse such as the black rat, Rattus rattus, in high conservation priority areas where multiple non-target species persist. This study investigates the effectiveness of camera trapping for monitoring invasive rodents in high conservation areas, and the influence of habitat features and density of colonial-nesting seabirds on rodent relative activity levels to provide insights into their potential impacts. A total of 276 camera sites were established and left in situ for 8 days. Identified species were recorded in discrete 15 min intervals, referred to as ‘events’. In total, 19 804 events were recorded. From these, 31 species were identified comprising 25 native species and six introduced. Two introduced rodent species were detected: the black rat (90% of sites), and house mouse Mus musculus (56% of sites). Rodent activity of both black rats and house mice were positively associated with the structural density of habitats. Density of seabird burrows was not strongly associated with relative activity levels of rodents, yet rodents were still present in these areas. Camera trapping enabled a large number of rodents to be detected with confidence in site-specific absences and high resolution to quantify relative activity levels. This method enables detection of multiple species simultaneously with low impact (for both target and non-target individuals); an ideal strategy for monitoring trap-adverse invasive rodents in high conservation areas. [ABSTRACT FROM AUTHOR]

Body size is often associated with a dietary divergence within taxonomically related groups so that large animals are often folivorous, while smaller species shift progressively towards omnivory or carnivory. This trend may be influenced by allometric constrains which result in relatively high energetic requirements, but low gut capacities in small animals, compared to their large counterparts. The common brushtail possum ( Trichosurus vulpecula, Phalangeridae) has six subspecies ranging widely in weight (1-4 kg). They are not strictly folivorous, but supplement their diet with more nutritious, non-foliar foods. We predicted that T. vulpecula subspecies diverged in diet in association with body size, with smaller subspecies consuming higher proportions of non-foliar foods. We assessed this with a review and a meta-analysis of previous Australian studies. We also investigated the previously unquantified diet of T. v. hypoleucus at three sites in the northern jarrah forest of Western Australia. Results from the meta-analysis and the review supported our prediction. However, the large variability in the data highlighted their limitations and those of the techniques commonly used to quantify the diet of T. vulpecula. Nonetheless, small subspecies of T. vulpecula appear to consume higher proportions of non-foliar foods. These results should encourage further research into the body size/diet relationship within T. vulpecula and other possum species. Results from the dietary study of T. v. hypoleucus emphasized their omnivorous diet, which was dominated by foliage and flowers and smaller proportions of invertebrates, seeds and fruits. The common brushtail possum is seldom an exclusive arboreal folivore, but rather ranges from folivory to omnivory. [ABSTRACT FROM AUTHOR]

The koomal (Trichosurus vulpecula hypoleucus) is a declining subspecies ('near-threatened'), residing largely within the Western Australian jarrah forest, a forest managed for both conservation and for forestry (roughly half is available for logging). Information on the spatial dynamics of koomal is essential to evaluating whether logging prescriptions provide adequate protection for this threatened species. Here we describe the home range and territoriality of koomal, as well as the characteristics and use of their den trees, at multiple sites within the jarrah forest. We also compare the characteristics of den trees used by koomal against logging prescriptions and previous models that estimate availability of den trees. Results suggested that koomal home ranges varied between sites and sexes, with males having the larger home ranges. Koomal also maintained exclusive core territories, probably to protect their den trees from same-sex individuals. Den trees used by koomal had similar characteristics to those outlined in logging prescriptions, but also included two additional characteristics that may improve the retention of trees suitable for koomal: den trees were preferentially of marri (Corymbia calophylla) and wandoo (Eucalyptus wandoo) species, and had some level of canopy connectivity. Overall, findings from this study should help future evaluations of the effectiveness of logging prescriptions in providing adequate den availability for koomal. We provide information on the spatial ecology of koomal (Trichosurus vulpecula hypoleucus) in the jarrah forest, along with an evaluation of models estimating den availability, and estimates of their hollow tree requirements at varying population densities. This information should aid future evaluations of whether logging prescriptions provide sufficient hollow trees for koomal. [ABSTRACT FROM AUTHOR]

Populations of feral house mice ( Mus domesticus L.) in Australia undergo multiannual fluctuations in density, and these outbreaks may be partly driven by some change in behavioural self-regulation. In other vertebrate populations with multiannual fluctuations, changes in kin structure have been proposed as a causal mechanism for changes in spacing behaviour, which consequently result in density fluctuations. We tested the predictions of two alternative conceptual models based on kin selection in a population of house mice during such an outbreak. Both published models ( ; ) propose that the level of relatedness between interacting individuals affects their behavioural response and that this changes with population density, though the nature of this relationship differs between the two models. Neither of the models was consistent with all observed changes in relatedness between interacting female mice; however, our results suggested that changes in kin structure still have potential for explaining why mouse outbreaks begin. Therefore, we have developed a variant of one of these conceptual models suggesting that the maintenance of female kin groups through the preceding winter significantly improves recruitment during the subsequent breeding season, and is therefore necessary for mouse outbreaks. We provide six testable predictions to falsify this hypothesis. [ABSTRACT FROM AUTHOR]

Beta-phase gallium oxide (β -Ga2O3) is a promising semiconductor for high frequency, high temperature, and high voltage applications. In addition to the β -phase, numerous other polymorphs exist and understanding the competition between phases is critical to control practical devices. The phase formation sequence of Ga2O3, starting from amorphous thin films, was determined using lateral-gradient laser spike annealing at peak temperatures of 500–1400 °C on 400 μs to 10 ms timescales, with transformations characterized by optical microscopy, x-ray diffraction, and transmission electron microscopy (TEM). The resulting phase processing map showed the γ -phase, a defect-spinel structure, first nucleating under all annealing times for temperatures from 650 to 800 °C. The cross-sectional TEM at the onset of the γ -phase formation showed nucleation near the film center with no evidence of heterogeneous nucleation at the interfaces. For temperatures above 850 °C, the thermodynamically stable β -phase was observed. For anneals of 1–4 ms and temperatures below 1200 °C, small randomly oriented grains were observed. Large grains were observed for anneals below 1 ms and above 1200 °C, with anneals above 4 ms and 1200 °C resulting in textured films. The formation of the γ -phase prior to β -phase, coupled with the observed grain structure, suggests that the γ -phase is kinetically preferred during thermal annealing of amorphous films, with β -phase subsequently forming by nucleation at higher temperatures. The low surface energy of the γ -phase implied by these results suggests an explanation for the widely observed γ -phase inclusions in β -phase Ga2O3 films grown by a variety of synthesis methods. [ABSTRACT FROM AUTHOR]

(SnSe)1.2TiSe2 was found to self-assemble from a precursor containing modulated layers of Sn-Se and Ti-Se over a surprisingly large range of layer thicknesses and compositions. The constituent lattices form an alternating layer superstructure with rotational disorder present between the layers. This compound was found to have the highest Seebeck coefficient measured for analogous TiX2 containing misfit layered compounds to date, suggesting potential for low-temperature thermoelectric applications. Electrical characterization suggests that electrons transferred from SnSe to TiSe2 are responsible for the higher carrier concentration observed relative to bulk TiSe2. The transfer of charge from one constituent to the other may provide a mechanism for doping layered dichalcogenides for various applications without negatively affecting carrier mobility. [ABSTRACT FROM AUTHOR]

Thin films of the new title intergrowth compound consisting of a bilayer of SnSe and TiSe2 trilayer are prepared by self-assembly from a precursor containing modulated layers of Sn-Se and Ti-Se, which is synthesized by deposition of elemental layers (annealing at 350 °C). [ABSTRACT FROM AUTHOR]

Autonomous experimentation enabled by artificial intelligence offers a new paradigm for accelerating scientific discovery. Nonequilibrium materials synthesis is emblematic of complex, resource-intensive experimentation whose acceleration would be a watershed for materials discovery. We demonstrate accelerated exploration of metastable materials through hierarchical autonomous experimentation governed by the Scientific Autonomous Reasoning Agent (SARA). SARA integrates robotic materials synthesis using lateral gradient laser spike annealing and optical characterization along with a hierarchy of AI methods to map out processing phase diagrams. Efficient exploration of the multidimensional parameter space is achieved with nested active learning cycles built upon advanced machine learning models that incorporate the underlying physics of the experiments and end-to-end uncertainty quantification. We demonstrate SARA’s performance by autonomously mapping synthesis phase boundaries for the Bi 2 O 3 system, leading to orders-of-magnitude acceleration in the establishment of a synthesis phase diagram that includes conditions for stabilizing δ-Bi 2 O 3 at room temperature, a critical development for electrochemical technologies.

Solid-state reaction kinetics on atomic length scales have not been heavily investigated due to the long times, high reaction temperatures, and small reaction volumes at interfaces in solid-state reactions. All of these conditions present significant analytical challenges in following reaction pathways. Herein we use in situ and ex situ X-ray diffraction, in situ X-ray reflectivity, high-angle annular dark field scanning transmission electron microscopy, and energy-dispersive X-ray spectroscopy to investigate the mechanistic pathways for the formation of a layered (Pb 0.5 Sn 0.5 Se) 1+δ (TiSe 2 ) m heterostructure, where m is the varying number of TiSe 2 layers in the repeating structure. Thin film precursors were vapor deposited as elemental-modulated layers into an artificial superlattice with Pb and Sn in independent layers, creating a repeating unit with twice the size of the final structure. At low temperatures, the precursor undergoes only a crystallization event to form an intermediate (SnSe 2 ) 1+γ (TiSe 2 ) m (PbSe) 1+δ (TiSe 2 ) m superstructure. At higher temperatures, this superstructure transforms into a (Pb 0.5 Sn 0.5 Se) 1+δ (TiSe 2 ) m alloyed structure. The rate of decay of superlattice reflections of the (SnSe 2 ) 1+γ (TiSe 2 ) m (PbSe) 1+δ (TiSe 2 ) m superstructure was used as the indicator of the progress of the reaction. We show that increasing the number of TiSe 2 layers does not decrease the rate at which the SnSe 2 and PbSe layers alloy, suggesting that at these temperatures it is reduction of the SnSe 2 to SnSe and Se that is rate limiting in the formation of the alloy and not the associated diffusion of Sn and Pb through the TiSe 2 layers.

Single- and few-layer metal chalcogenide compounds are of significant interest due to structural changes and emergent electronic properties on reducing dimensionality from three to two dimensions. To explore dimensionality effects in SnSe, a series of [(SnSe) 1+δ ] m TiSe 2 intergrowth structures with increasing SnSe layer thickness (m = 1-4) were prepared from designed thin-film precursors. In-plane diffraction patterns indicated that significant structural changes occurred in the basal plane of the SnSe constituent as m is increased. Scanning transmission electron microscopy cross-sectional images of the m = 1 compound indicate long-range coherence between layers, whereas the m ≥ 2 compounds show extensive rotational disorder between the constituent layers. For m ≥ 2, the images of the SnSe constituent contain a variety of stacking sequences of SnSe bilayers. Density functional theory calculations suggest that the formation energy is similar for several different SnSe stacking sequences. The compounds show unexpected transport properties as m is increased, including the first p-type behavior observed in (MSe) m (TiSe 2 ) n compounds. The resistivity of the m ≥ 2 compounds is larger than for m = 1, with m = 2 being the largest. At room temperature, the Hall coefficient is positive for m = 1 and negative for m = 2-4. The Hall coefficient of the m = 2 compound changes sign as temperature is decreased. The room-temperature Seebeck coefficient, however, switches from negative to positive at m = 3. These properties are incompatible with single band transport indicating that the compounds are not simple composites.

Targeted heterostructures containing intergrown two dimensional (2D) layers of 3 different constituent layers, SnSe2, PbSe and TiSe2, were prepared by controlling the composition and sequence of elemental bilayers within a designed precursor. Varying the structure of the precursor enabled the number of structural units of each constituent and the sequence of crystalline 2D layers to be precisely controlled. The stacking of the 2D layers, their structures, and the segregation of the elements between them were determined using X-ray diffraction and electron microscopy techniques, with the observed sequence of the 2D layers consistent with the targeted intergrowth. This ability to prepare targeted heterostructures is critical, since the number of possible configurations in the final compound increases rapidly as the number of constituents increases, from almost 60 000 with two constituents to over 130 million with three constituents and to over 35 billion with four constituents for 20 or fewer distinct layers in the unit cell. This general route for synthesizing specific multiple component heterostructures will accelerate the feedback loop in this growing research area, permitting theorists to assume specific structures in the search for enhanced properties and providing experimentalists with crystallographically aligned samples to test these predictions.