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Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought.

Climate change is altering fire regimes globally, leading to an increased incidence of large and severe wildfires, including gigafires (>100,000 ha), that homogenise landscapes. Despite this, our understanding of how large, severe wildfires affect biodiversity at the landscape scale remains limited.We investigated the impact of a gigafire that occurred during the unprecedented 2019–20 Australian 'Black Summer' on terrestrial fauna. We selected 24 study landscapes, each 0.785 km2 in size, that represented a gradient in the extent of high severity fire, unburnt vegetation, and the diversity of fire severity classes ('pyrodiversity'). We used wildlife cameras to survey biodiversity across each landscape and quantified species activity, community and functional diversity, and predator–prey network metrics. We used Bayesian mixed‐effects models to assess the influence of fire‐induced landscape properties on these measures.Most native species showed resilience to the 2019–20 wildfires, displaying few relationships with fire‐induced properties of landscapes, including the extent of high severity fire, unburnt vegetation, or pyrodiversity.Community and functional diversity and measures of predator–prey networks were also largely unaffected by fire‐induced landscape properties, although landscapes with a greater proportion of high severity fire had higher abundance and richness of introduced animal species.Synthesis and applications: Despite prevailing narratives of widespread ecological destruction following the 2019–20 wildfires, our findings suggest widespread resilience, potentially facilitated by evolutionary adaptations of animals to fire. Interventions aimed at helping such species recover may not be necessary and could instead focus on the subset of species that are vulnerable to severe fire. While mixed‐severity fires are often advocated to promote biodiversity through pyrodiversity, our results suggest that such management efforts might not be necessary in our study region. Given that severe fire favours introduced animal species, invasive species management could focus on large, severely burnt areas. [ABSTRACT FROM AUTHOR]

Motivation: Terrestrial predators play key roles in cycling nutrients, as well as limiting prey populations, and shaping the behaviour of their prey. Prehistoric, historic and ongoing declines of the world's predators have reshaped terrestrial ecosystems and are a topic of conservation concern. However, the availability of ecologically relevant predator functional traits is limited, hampering efforts to understand macroecological changes in this ecologically important functional group. Here, we present CarniTraits, a comprehensive open‐access functional trait database of all late Quaternary (~130,000 ybp) terrestrial mammalian predators (149 species, ≥1 kg body mass, ≥50% vertebrate meat consumption). Main Types of Variables Contained: Mammalian terrestrial predator functional traits including body mass, diet, scavenging, locomotion, cooperative hunting, hunting habitat, hunting method, bone consumption, temporal activity patterns, brain mass and encephalisation quotient. Spatial Location and Grain: Global. Time Period and Grain: Late Quaternary (the last ~130,000 years). Major Taxa and Level of Measurement: All late Quaternary terrestrial mammalian predators (149 species, ≥1 kg body mass, ≥50% vertebrate meat consumption). Software Format: csv. [ABSTRACT FROM AUTHOR]

Males of the endangered northern quoll (Dasyurus hallucatus) are facultatively semelparous, often dying following their first breeding season. This is often driven by high breeding costs: males travel and mate extensively in breeding season, resulting in reduced body condition. Annual post‐breeding survival rates for male northern quolls have been recorded between 0% and 12.5% across their range in northern Australia. We highlight an observed 50% survival rate of male northern quolls (3 of 6) living into their second year in a Pilbara mining landscape. High male survival here may be attributed to above average rainfall in the landscape and reduced breeding opportunities, due to low female abundance—likely driven by large amounts of unfavourable mining land. This likely led to lower hormonal stress associated with breeding for males, as well as increased resource availability. Given northern quoll population persistence is highly dependent on breeding success, high survival of male northern quolls may inadvertently stabilize populations if they can breed again in a second year, though this is yet to be observed in the Pilbara region. Nevertheless, semelparity of male northern quolls likely varies with environmental and demographic factors, demonstrating that northern quoll populations may be resilient to disturbance in an unpredictable semi‐arid environment. [ABSTRACT FROM AUTHOR]

Water scarcity, a challenge expected to worsen with climate change, significantly hinders native plant community restoration. Enhancing seed‐based restoration requires methods to increase the water availability for seeds and seedlings. Surfactants and superabsorbent polymers (SAPs) can improve soil water‐holding capacity and infiltration, but their use in seed enhancements remains underexplored. We investigated whether pellets containing surfactants or SAPs could improve seedling emergence of two native species (Rytidosperma caespitosum and Chrysocephalum apiculatum) common in temperate grasslands in south‐eastern Australia under different watering treatments. We used a randomized block design with five watering treatments to simulate predicted changes in precipitation for south‐eastern Australia: ambient, two reducing overall water volume, and two reducing watering frequency while increasing watering volume to maintain ambient treatment water volume. We explored four enhanced pellets (two containing surfactants and two containing SAPs) and non‐pelleted seeds. Our results showed that watering events with larger volumes but reduced frequency increased seedling emergence. Under these conditions, block co‐polymer surfactants further increased seedling emergence of C. apiculatum, while synthetic SAP pellets promoted emergence of R. caespitosum. Block co‐polymer surfactants decreased R. caespitosum emergence, and both SAPs reduced C. apiculatum emergence under reduced watering frequency. A 50% reduction in overall water volume significantly reduced seedling emergence for both species, regardless of seed enhancement. These findings suggest that surfactants and SAP pellets can improve the success of seed‐based restoration under ambient conditions and when rainfall events are larger in volume but reduced in frequency, but not when the overall volume of rainfall is reduced. [ABSTRACT FROM AUTHOR]

Ornamentation of parents poses a high risk for offspring because it reduces cryptic nest defence. Over a century ago, Wallace proposed that sexual dichromatism enhances crypsis of open-nesting females although subsequent studies found that dichromatism per se is not necessarily adaptive. We tested whether reduced female ornamentation in a sexually dichromatic species reduces the risk of clutch depredation and leads to adaptive parental roles in the red-capped plover Charadrius ruficapillus, a species with biparental incubation. Males had significantly brighter and redder head coloration than females. During daytime, when visually foraging predators are active, colour-matched model males incurred a higher risk of clutch depredation than females, whereas at night there was no difference in depredation risk between sexes. In turn, red-capped plovers maintained a strongly diurnal/nocturnal division of parental care during incubation, with males attending the nest largely at night when visual predators were inactive and females incubating during the day. We found support for Wallace's conclusion that reduced female ornamentation provides a selective advantage when reproductive success is threatened by visually foraging predators. We conclude that predators may alter their prey's parental care patterns and therefore may affect parental cooperation during care.

Sampling of environmental DNA (eDNA) and high‐throughput sequencing is emerging as an effective biodiversity assessment method in aquatic systems and may have utility for biodiversity inventory in terrestrial environments. Rock pools (gnammas) on granite inselbergs support a rich community of aquatic organisms and are culturally important to Indigenous peoples worldwide. However, the application of eDNA to survey rock pool biodiversity are undocumented. In a collaborative study with traditional owners, we explore the application of eDNA metabarcoding and traditional sampling methods to document and compare species richness and composition of eukaryotes from 15 rock pools (pits and pans) on granite inselbergs in southeastern Australia. We detected 116 taxonomic units, 81 assignments from eDNA sequencing and 35 species (23 rotifers and 12 microcrustaceans) using microscopic analysis. eDNA detected a broad range of taxa not previously documented from rock pools in Australia, although significantly more zooplankton (rotifers and microcrustaceans) were detected under a microscope, including several rare species and two undescribed species of rotifer. Brachionus calyciflorus and B. angularis were the only rotifer species assigned to species level through eDNA sequencing and were detected using both methods. We found no significant difference in mean species richness between rock pool types; however, species composition differed significantly between pits and pans. This study highlights the value of using eDNA to document biodiversity of ephemeral aquatic habitats in terrestrial ecosystems but reveals the general lack of reference sequence data for microorganisms, underscoring the value of using traditional sampling and taxonomic assignment methods. [ABSTRACT FROM AUTHOR]

Ecosystem engineers modify their environment and influence the availability of resources for other organisms. Burrowing species, a subset of allogenic engineers, are gaining recognition as ecological facilitators. Burrows created by these species provide habitat for a diverse array of other organisms. Following disturbances, burrows could also serve as ecological refuges, thereby enhancing ecological resistance to disturbance events. We explored the ecological role of Common Wombat (Vombatus ursinus) burrows using camera traps in forests of southeastern Australia. We compared animal activity at paired sites with and without burrows, from the same fire severity class and habitat. We examined how animal activity at Common Wombat burrows was affected by the 2019–20 Black Summer bushfires in Australia. We predicted that burrows would serve as hotspots for animal activity and as refuges in burned areas. The activity of several species including Bush Rat (Rattus fuscipes), Agile Antechinus (Antechinus agilis), Lace Monitor (Varanus varius), Painted Button-quail (Turnix varius), and Grey Shrike-thrush (Colluricincla harmonica) increased at sites where Common Wombat burrows were present, while other species avoided burrows. Species that were more active at burrows tended to be smaller mammal and bird species that are vulnerable to predation, whereas species that avoided burrows tended to be larger mammals that might compete with Common Wombat for resources. Species composition differed between sites with and without burrows, and burrow sites had higher native mammal species richness. The association of several species with burrows persisted or strengthened in areas that burned during the 2019–20 Black Summer bushfires, suggesting that Common Wombat burrows may act as ecological refuges for animals following severe wildfire. Our findings have relevance for understanding how animals survive, persist, and recover following extreme wildfire events. [ABSTRACT FROM AUTHOR]

Context: Fire regimes are changing with ongoing climate change, which is leading to an increase in fire frequency and severity. Australia's Black Summer wildfires burned >12 million hectares in 2019–2020, affecting numerous threatened animal species. One of the species predicted to be most impacted was the threatened southern greater glider, an arboreal, hollow-dependent folivore, endemic to eastern Australia's eucalypt forests. Aims: This study aimed to assess how the 2019–2020 wildfires affected greater glider abundance and the resources they depend on in Woomargama National Park, New South Wales, Australia. Methods: We categorised 32 sites into four fire severity treatments with eight sites for each treatment: unburned (continuous unburned vegetation); refuges (unburned patches within the fire's perimeter); low-moderate severity; and high severity. We carried out two spotlight surveys per site using the double-observer method, beginning 21 months after the fires. We also conducted vegetation assessments on the same transects. To analyse the data, we used Generalised Linear Models to compare habitat differences based on fire severity, and N-mixture models to model greater glider detectability and abundance in relation to habitat and fire severity. Key results: We found that fire severity depleted several habitat variables including canopy cover and the number of potentially hollow-bearing trees, a resource that greater gliders rely on. Greater glider abundance also decreased in all burn categories, with the greatest decline experienced in areas burned at high severity. We also found that greater glider abundance was much lower in fire refuges than unburned habitat outside of the fire zone. Conclusions: Greater glider declines following severe wildfire can be at least partly attributed to the level of vegetation loss and the associated loss of key habitat resources. The contribution of direct mortality to population declines remains unknown. Implications: Greater glider conservation will rely heavily on protecting expansive unburned areas of suitable habitat and maintaining hollow-bearing trees. This study aimed to assess the impact of the 2019–2020 wildfires on the abundance of the southern greater glider in Woomargama National Park, New South Wales, Australia. Our results indicated that southern greater glider populations were lower in areas that burned during the fires, as well as in small, unburned refuges. These declines were linked to the loss of critical resources, such as an intact canopy and hollow-bearing trees. Photograph by Mikayla Green. [ABSTRACT FROM AUTHOR]

Despite being a central aspect of a species' ecology and having important conservation implications, the use of fine‐scale habitat features (microhabitats), and how they vary over time, are poorly known for most species. In this study, we leveraged 522 relocations of radio‐tracked mallee tree dragons (Amphibolurus norrisi) and painted dragons (Ctenophorus pictus) to investigate the effect of environmental and individual variables on microhabitat use. Mallee tree dragons were more likely to use trees on hot days and in the middle of the day (the hottest time of day), whereas shrub use was more likely on cool days and in the mornings. Painted dragons were more likely to use shrubs and grass trees on warmer days and during the middle of the day, whereas burrows were used during cooler days and in the mornings and afternoons. We expect these patterns represent animals moving from refuge resources, occupied during unsuitable thermal conditions, to microhabitats offering basking, foraging and social opportunities during periods of thermal optimum. Additionally, we found evidence of an ontogenetic shift, with larger mallee tree dragons favouring tree use and higher perches, suggesting a transition from shrub to tree use with age. Our findings underscore the need for diverse microhabitats to accommodate the thermoregulatory and ontogenetic requirements of lizards. These insights can inform conservation and habitat restoration efforts, ensuring the provision of essential microhabitats to support species persistence. [ABSTRACT FROM AUTHOR]

Context: Freshwater ecosystems rank among the most threatened environments on Earth. Monitoring aquatic and semi-aquatic species is vital to informing conservation of freshwater ecosystems. However, many semi-aquatic mammals can be difficult to detect with conventional survey methods. Aims: We aimed to identify the most effective survey method for detecting an Australian semi-aquatic mammal, the rakali (Hydromys chrysogaster). Methods: We compared rakali detection rates among camera-trapping, live-trapping and visual surveys, and tested the influence of camera angle, trap proximity to water and time of survey, across the Yanco Creek system in southern New South Wales. Key results: Nocturnal spotlight surveys were the most effective method for detecting rakali, with most observations occurring while individuals were foraging or swimming in the water. Camera traps facing a floating platform and cage traps mounted on floating platforms performed better than those deployed on land. Downward-facing camera traps detected rakali three times more often than did forward-facing cameras. Trapping rakali was unreliable, with the species detected at fewer than half of the sites where presence was confirmed via visual observation and camera traps. For species absence to be determined with 95% confidence, 2–4 weeks of nightly trapping is required, compared with six nights of visual surveys or 12 nights for a platform-facing camera. Morning visual surveys were largely ineffective because of predominantly nocturnal rakali activity and difficulty in detecting signs in creek environments. Conclusions: The likelihood of detecting rakali can be maximised through the use of nightly spotlighting and deployment of baited camera traps focussed on platforms or natural resting areas within a water body. Implications: Understanding the effectiveness of each method is essential for developing species-appropriate protocols for population monitoring. Our findings present suitable options to be further explored among the 100-plus small (<1 kg) semi-aquatic mammals worldwide that share similar behaviours and characteristics to the rakali, many of which are threatened or data deficient. Cryptic semi-aquatic mammals present a particular challenge to monitor because of their unique lifestyles. We aimed to identify the most effective methods to detect the seldom-studied rakali, a native Australian semi-aquatic mammal; spotlighting and camera traps placed over water provided the greatest detection probabilities. We present a novel method to monitor rakali, which has the potential to improve the detection and conservation of other small semi-aquatic mammals. Photograph by Emmalie Sanders. [ABSTRACT FROM AUTHOR]