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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]

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]