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Abstract Termite mounds are keystone structures in African savannas, affecting multiple ecosystem processes. Despite the large size of termite mounds having the potential to modify conditions around them, patterns of mound‐induced ecosystem effects have been assumed to be isotropic, with little attention given to how effects might vary around mounds. We measured soil nitrogen content, grass species composition, and mammalian grazing on and off termite mounds in the four cardinal directions, and across wet and dry seasons at three savanna sites varying in mean annual rainfall in South Africa's Kruger National Park. Evidence of directional effects (anisotropy) on ecosystem properties around termite mounds varied with site. Grass species composition differed between north‐ and south‐facing slopes at the two drier sites where mounds were taller. However, differences in grazing extent and soil nitrogen content around mounds were only present at the intermediate rainfall site where mammalian herbivore biomass was highest, and mounds were of medium height. Our results suggest that termite mound effects display significant variation with direction, but that the emergence of directional effects is context dependent. Our results further suggest that such context‐dependent directional effects can lead to positive feedback loops between termites, abiotic conditions, and mammalian herbivores.

The Endangered dhole Cuon alpinus is a medium-sized canid that was historically distributed widely across East, Central, South and Southeast Asia. In Nepal, following heavy persecution during the 1970s and 1980s, the species was locally extirpated across large parts of the country. After decades of near absence, the dhole is reportedly showing signs of recovery in various areas of Nepal. We carried out three surveys using camera traps (resulting in a total of 6,550 camera-trap days), reviewed literature and interviewed herders and conservation practitioners (40 interviews) to determine the historical and current distribution of dholes in the country, and the species’ current status. Our camera traps recorded five images of dholes, and the literature review and interview survey provided further insights into the historical and current presence of dholes in Nepal. The combined findings suggest dholes have recolonized many areas where they had been locally extirpated, such as the Annapurna Conservation Area in central Nepal and the Tinjure–Milke–Jaljale forests in the eastern part of the country. Although these returns are encouraging, challenges remain for dhole recolonization, including conflict with livestock herders, human hunting of wild ungulates affecting the species’ prey base, increasing infrastructure development in forested areas, and diseases.

Abstract Passive acoustic recorders have emerged as powerful tools for ecological monitoring. However, effective monitoring is not simply an act of recording sounds. To have meaning for conservation and management, acoustic monitoring needs to be properly planned and analyzed to yield high quality information. Here, we provide a set of considerations for the design of an effective acoustic monitoring program. We argue that such a program, has the following attributes: (1) has established appropriate partnerships with landowners, Traditional Owners, researchers, or other relevant stakeholders, (2) is based on clear objectives and questions, (3) is explicit in its target sound signals, (4) has considered in‐field sensor placement for a range of factors, including experimental design, statistical power, background noise, and potential impacts on human privacy and animal disturbance, (5) has a justified recording schedule and periodicity, (6) has methods to process sound data in line with objectives, and (7) has protocols for permanent data storage and access. Acoustic monitoring is increasingly used in large‐scale programs and will be important in addressing global biodiversity targets and new biodiversity markets. It is critical that new monitoring programs are designed to effectively and efficiently capture data that address pertinent and emerging issues in conservation.

Termite mounds are keystone structures in African savannas, affecting multiple ecosystem processes. Despite the large size of termite mounds having the potential to modify conditions around them, patterns of mound‐induced ecosystem effects have been assumed to be isotropic, with little attention given to how effects might vary around mounds. We measured soil nitrogen content, grass species composition, and mammalian grazing on and off termite mounds in the four cardinal directions, and across wet and dry seasons at three savanna sites varying in mean annual rainfall in South Africa's Kruger National Park. Evidence of directional effects (anisotropy) on ecosystem properties around termite mounds varied with site. Grass species composition differed between north‐ and south‐facing slopes at the two drier sites where mounds were taller. However, differences in grazing extent and soil nitrogen content around mounds were only present at the intermediate rainfall site where mammalian herbivore biomass was highest, and mounds were of medium height. Our results suggest that termite mound effects display significant variation with direction, but that the emergence of directional effects is context dependent. Our results further suggest that such context‐dependent directional effects can lead to positive feedback loops between termites, abiotic conditions, and mammalian herbivores. [ABSTRACT FROM AUTHOR]

Abstract Male frog advertisement calls are species‐specific vocalizations used to attract females for breeding. However, it is possible for environmental or biological sounds to overlap these calls in both frequency and duration resulting in signal confusion, influencing female decision and/or location abilities. It is therefore important for vocal species competing for the same acoustic space to partition their calls either spatially or temporally (via call alternation or suppression). However, frog species previously isolated from each other may not have developed appropriate adaptive behaviors, resulting in acoustic competition. This study applied rhythm analysis to track changes in calling behavior, namely changes in calling frequency (as in beats per second), of the wallum sedgefrog and the eastern sedgefrog when vocalizing alone versus in the presence of each other to assess potential acoustic competition. Our main findings demonstrated that both species significantly altered their calling behavior when exposed to each other. While we expected the increased calling activity of one species to inhibit the activity of the other to avoid signal confusion, we instead found that both species greatly increased the beat frequency of their calls when calling in the presence of each other. We also found evidence of beat frequency development in the wallum sedgefrog whereby there was always a strong initial increase in call frequency in reaction to the first vocal interruption by the eastern sedgefrog. These results support the hypothesis that the eastern sedgefrog and the wallum sedgefrog are in competition for the acoustic space in habitats where they occur together. This highlights a new threat to the vulnerable wallum sedgefrog species and may serve to inform future management practices. Using rhythm analyses to track changes in acoustic behavior can help inform on important population dynamics such as health, trajectory, and response to management, and therefore be of great benefit to the conservation of vocal species.

Many bird species in Australia require tree hollows for breeding. However, assessing the benefits of urban nest boxes to native birds requires frequent monitoring that allows to assess nesting success. To better understand the benefits of nest boxes for native birds, we examined the impact of local habitat characteristics, invasive species (common myna, Acridotheres tristis), and native mammalian predators on urban nest box use and nesting success of native birds. We installed 216 nest boxes across nine locations in southeastern Australia (S.E. Queensland and northern New South Wales) in both long-invaded sites (invaded before 1970) and more recently invaded sites (after 1990). We monitored all boxes weekly over two breeding seasons. We recorded seven bird species and three mammal species using the nest boxes. Weekly box occupancy by all species averaged 8% of all boxes, with the species most frequently recorded in the nest boxes being the common brushtail possum (Trichosurus vulpecula), a native cavity user and nest predator. We recorded 137 nesting attempts in the boxes across all bird species. The most frequent nesting species were the invasive alien common mynas (72 nesting attempts). We recorded an average nesting failure rate of 53.3% for all bird species. We did not record any common mynas evicting other nesting birds, and found that several native species used the same box after the common myna completed its nesting. We recorded native possums in 92% of the boxes, and possum occupancy of boxes per site was negatively correlated with bird nesting success (p = 0.021). These results suggest that when boxes are accessible to invasive species and native predators, they are unlikely to significantly improve nesting opportunities for native birds. To ensure efficient use of limited conservation resources, nest boxes should be designed to target species of high conservation importance and limit other species of both predators and competitors.

High‐pressure and high‐temperature experiments were conducted to simulate melting of a hybrid cumulate lunar mantle. The experimental results show that intermediate to high‐Ti lunar pyroclastic glasses (>6 wt% TiO2) can be produced by partial melting of lunar cumulates. High‐Ti basalts are generated when the ilmenite/clinopyroxene ratios in the lunar mantle cumulates are between 1/1 and 4/1, depending on the degree of melting. The presence of an urKREEP component in the mantle cumulate strongly influences Al2O3/CaO of the melts. The experiments provide strong evidence for the model that the compositional diversity of lunar basalts is a consequence of a gravitational overturn of the lunar interior after the lunar magma ocean had solidified. Ilmenite/clinopyroxene in the cumulate mantle, which generates high‐Ti melts at partial melting, do not comprise the ratios in ilmenite‐bearing cumulates (IBC), which crystallized after ∼90% solidification of the lunar magma ocean and indicate local accumulation of ilmenite in the overturned lunar mantle. However, to fully match the natural composition of the most primitive lunar samples, secondary processes such as assimilation are still required. Plain Language Summary: The basalt samples, which were returned from the Earth's Moon by astronauts during sample return missions, are chemically different from terrestrial basalts. Whilst terrestrial basalts usually contain less than 1 wt% of TiO2, the lunar rocks can contain more than >6 wt% of TiO2. The origin of these extraordinarily high TiO2 contents has long been debated, and hence we conducted experiments at high pressures and temperatures to simulate melting of a heterogeneous lunar mantle. Our experimental results imply that the lunar high‐Ti basalts can be produced by melting of a heterogeneous lunar mantle that contains high amounts of Ti‐rich minerals, such as ilmenite or similar Fe and Ti‐rich oxides, and silicate minerals, such as olivine, orthopyroxene, and clinopyroxenes. Our results support the hypothesis that the stratification of the lunar mantle after it had solidified was not preserved, suggesting a high dgree of heterogeneity within the mantle. Besides Ti, other major elements of our melts do not completely match the natural samples. This can be accounted for by interaction with the host rocks during the ascent of the magmas. Key Points: High‐Ti lunar basalts can be produced experimentally by a simple melting process of a hybrid lunar cumulate mantle with nonmodal ilmenite/clinopyroxeneThe entire chemical spectrum of most primitive lunar basalts requires additional processes such as reactive ascent and assimilationThe process of partially melting a heterogeneous lunar mantle also yields melts with similarities to low‐Ti, high‐Al lunar mare basalts [ABSTRACT FROM AUTHOR]

Phlogopite and K‐richterite constitute important carrier phases for H and F in Earth's lithosphere and mantle. The relative importance depends on their stabilities at high pressure and temperature, which in turn depends on bulk composition. Most previous experimental studies focused on the thermal stability of phlogopite and K‐richterite were conducted using simplified chemical compositions. Here, partial melting experiments on metasomatized and carbonated, OH ± F‐bearing near‐natural peridotite were performed at high pressures (2 and 5 GPa) and temperatures (1,100–1,350°C) to assess the thermal stability of F‐free versus F‐bearing phlogopite and K‐richterite. Experimental results demonstrate that the thermal stability of F‐bearing phlogopite is increased by >55°C/wt.% F, relative to F‐free phlogopite, whereas K‐richterite is absent in all experiments with significant degrees of melting (>2%). The thermal stability of phlogopite containing several wt.% F exceeds continental and oceanic geotherms within the upper 150 km. Fluorine‐rich phlogopite would therefore be stable in virtually all of the continental lithosphere, only to be decomposed during large, regional melting events such as continental break‐up, thereby acting as a major long‐term sink for F and/or H. This could even be the case for the oceanic asthenosphere, depending on the oceanic geotherm of the area of interest. Plain Language Summary: Phlogopite and K‐richterite are important minerals for the fluorine and hydrogen cycles of the Earth's interior. The effects of fluorine on the thermal stability of phlogopite and K‐richterite was studied using a suite of high pressure, high temperature experiments, mimicking partial melting in Earth's upper mantle and lower crust. The experimental results show that F dramatically enhances the stability of phlogopite, implying phlogopite can retain F and H up to greater depths in the Earth than previously assumed. Fluorine does not significantly affect the thermal stability of K‐richterite. Given that F is more compatible in phlogopite compared to H, our results show that phlogopite becomes increasingly more stable through time as F is preferentially incorporated over OH during fluid alteration at high temperatures. Fluorine‐rich phlogopite may only be decomposed during large, regional melting events, such as continental break‐up, thereby acting as a long‐term carrier of F and to a lesser extent OH in the Earth's lower crust and/or upper mantle. Key Points: Partial melting experiments on metasomatized peridotite were performed to assess the thermal stability of F‐bearing phlogopite and K‐richteriteThe thermal stability of phlogopite containing several wt.% F exceeds continental and oceanic geotherms within the upper 150 kmF‐rich phlogopite would be stable in virtually all continental lithosphere, thereby acting as a major long‐term sink for F and/or H [ABSTRACT FROM AUTHOR]

Abstract The acid frogs of eastern Australia are a highly specialized group of threatened species endemic to acidic coastal wetlands of southern Queensland and New South Wales. The distribution of these species overlaps with areas of increasing development where land‐use intensification poses a significant threat. Successful conservation of these species requires that areas of high conservation value for acid frogs are properly identified and protected, particularly in south‐east Queensland which supports important populations of all four acid frog species: Litoria olongburensis, Litoria freycineti, Crinia tinnula, and the Queensland‐endemic Litoria cooloolensis. Species distribution modeling using rigorously vetted species occurrence data was used to identify areas of potential acid frog habitat with >89% predictive power for all species. Key predictor variables for acid frog species occurrence included: soil sandiness, vegetation, presence and/or type of wetland, and soil clay content. All species' predicted distributions occurred primarily in coastal regions, overlapping with densely human‐populated areas. Our modeling and analysis of species' distributions highlight local government areas where protection of wallum habitat is most important for the conservation of acid frogs, as well as areas of higher conservation value providing habitat for multiple acid frog species.