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The 2019–2020 megafires in southeastern Australia extensively burnt forests including fire‐sensitive rainforests. Assessments of species' responses typically consider differences in occupancy or density between burnt and unburnt forest, but here we focus on how these fires influenced roost selection by a rainforest‐dependent bat. We radio‐tracked golden‐tipped bats Phoniscus papuensis in fire grounds to investigate whether roost location or type was influenced by fire severity one‐year post‐fire. Overall, we tracked 19 bats for a total of 117 roost‐days. Bats roosted (including maternity colonies) in the suspended nests of yellow‐throated scrub‐wrens and brown gerygone, typically in gully rainforest. No bats were captured, or roosts located, where fire severity was high. In the burnt portion of the northern study area, P. papuensis displayed a significant preference for roosting in unburnt rainforest compared to its availability along adjacent gullies. Patches of rainforest burnt by low–moderate severity fire were ranked as second preference. In the burnt portion of the southern study area, most roosts were in rainforest mapped as burnt by low–moderate fire severity, however, no selection was evident relative to availability of rainforest and mapped fire severity. Actual roost locations in the southern study area revealed that 62% were in small pockets of unburnt rainforest, with burnt areas nearby. We recorded early breeding and signs of a second litter in late summer, suggesting a post‐fire resource pulse in their prey (spiders). A higher than usual reproductive output may assist in recovery, along with the bat's mobility to aid finding remaining pockets of unburnt or low severity burnt rainforest with suitable bird nests for roosting. However, recolonization of rainforest burnt by high severity fire will first require recovery of structural complexity, microclimate and the recolonization of host bird‐built nests. We recommend ongoing monitoring to assess the recovery of this specialist bat. [ABSTRACT FROM AUTHOR]

Nipah virus (NiV) and Hendra virus (HeV) are highly pathogenic zoonotic viruses of the genus Henipavirus, family Paramyxoviridae that cause severe disease outbreaks in humans and also can infect and cause lethal disease across a broad range of mammalian species. Another related Henipavirus has been very recently identified in China in febrile patients with pneumonia, the Langya virus (LayV) of probable animal origin in shrews. NiV and HeV were first identified as the causative agents of severe respiratory and encephalitic disease in the 1990s across Australia and Southern Asia with mortality rates reaching up to 90%. They are responsible for rare and sporadic outbreaks with no approved treatment modalities. NiV and HeV have wide cellular tropism that contributes to their high pathogenicity. From their natural hosts bats, different scenarios propitiate their spillover to pigs, horses, and humans. Henipavirus-associated respiratory disease arises from vasculitis and respiratory epithelial cell infection while the neuropathogenesis of Henipavirus infection is still not completely understood but appears to arise from dual mechanisms of vascular disease and direct parenchymal brain infection. This brief review offers an overview of direct and indirect mechanisms of HeV and NiV pathogenicity and their interaction with the human immune system, as well as the main viral strategies to subvert such responses. [ABSTRACT FROM AUTHOR]

Insectivorous bats make a significant contribution to mammalian diversity in central Australia, with 12 known extant species; however, little is known about their habitat preferences and how these interact with temporal patterns in their abundance and activity. Although most species forage widely and in a variety of habitats, we expected that woodlands associated with ephemeral rivers would constitute high-value habitat for bats because they provide tree hollows, suitable structural habitat for foraging, and canopies rich in invertebrate biomass. The aim of this research was to establish whether riparian woodlands were a focus of bat activity and to identify patterns in habitat use and whether these changed through time. We investigated the activity of bats in riparian woodlands and neighbouring vegetation over 2 years. Bat activity was higher in riparian woodland than in nearby vegetation, and this difference was most significant during a hot and dry summer. At the species level, body size and foraging guild were important factors explaining differences in activity, with larger 'open space' species more active in riparian woodland than adjacent habitat. In contrast, we did not detect significant differences in the activity of smaller vespertilionid species between habitats. Coinciding with patterns in invertebrate activity, bat activity was highest in summer and lowest in winter. Within river channels, canopy cover was important in explaining patterns in bat activity. There was also a significant location effect, with bat activity in some river systems much higher than in others. We propose that this is related to both regional variability in rainfall and productivity, in addition to topography. Our findings demonstrate the importance of riparian woodlands to bats in an arid environment, particularly during low-resource periods, and suggest that bats may be affected by future climate changes and degradation from fire impacts. Insectivorous bats make a significant contribution to mammalian diversity in central Australia, with 12 known extant species, yet little is known about their habitat preferences and how these interact with temporal patterns in their abundance and activity. We found that bat activity was higher in arid riparian woodland than in nearby vegetation, and this difference was most significant during a hot and dry summer. Our findings demonstrate the importance of riparian woodlands to bats in an arid environment, particularly during low-resource periods [ABSTRACT FROM AUTHOR]

Biodiversity monitoring is recognised as a key action for ecologically sustainable land use, but there are few examples of landscape programmes. We outline the first five years of biodiversity monitoring focusing on insectivorous bats in low rainfall, multiple‐use forests and woodlands of the Pilliga, Australia. Using ultrasonic sampling over multiple nights, both on‐ and off‐tracks, we identify annual trends in bat activity and occupancy and environmental covariates. Trends differed depending on whether occupancy or bat activity was the response variable. Site occupancy was almost 100% and remained stable and/or did not decline for most species nor diversity over the monitoring period, suggesting little variation in bat populations. In comparison, total activity was initially very high (567 passes night−1 on‐track) and then declined by up to 40% in the following three years, but then fully recovered in the fifth year. This general pattern was evident both on‐ and off‐tracks for most taxa, though activity was three times greater on‐ than off‐track, highlighting the importance of these distinct habitat features for bats. Multivariate state‐space (MARSS) models predicted, unexpectedly, that high winter rainfall prior to our surveys was negatively related to activity for many taxa. In contrast, disturbance from timber harvesting or fire had weak or no identifiable effects on trends in activity for most taxa. One exception was Chalinolobus picatus (threatened), whose occupancy off‐tracks was negatively related to the extent of recent (<5 years) fire and to harvesting, though at the landscape scale, occupancy remained stable. This result, together with patterns for other bat taxa, suggests that disturbance effects were short‐lived/dispersed and/or environmental mitigations were effective at maintaining bat populations at a landscape level. Annual monitoring highlighted annual variation in activity and its implications when setting a baseline for monitoring. We also discuss modifications to future monitoring effort, based on the existing five years of data. [ABSTRACT FROM AUTHOR]

In Australia, there are at least 50 000 derelict mines, many of which provide habitat for cave-roosting bats. Grating of derelict mines, be it horizontal (adits) or vertical (shafts) drives, is commonly undertaken to prevent human access, though longer-term responses of bats are largely unknown. We assessed the long-term (2–20 years) effects of grating on bats by documenting trends in emergence activity and bat abundance at grated and ungrated derelict mines and quantified behavioural responses of bats in autumn and winter. Emergence activity was dominated by the eastern horseshoe bat (Rhinolophus megaphyllus) with limited activity of other less manoeuvrable species. Both emergence activity and minimum colony size at horizontal adits were 8–9 times greater than at vertical shafts, with bats observed emerging from only 2 of 13 shafts. Emergence activity and minimum colony size were 7–10 times greater at adits with 'bat friendly' grating (horizontal bars with spacing >125 mm) than at other treatments (ungrated adits and adits with standard grating). In winter, there were 4–11 times more aborted exit attempts per bat at adits with 'bat friendly' grating compared with other treatments, which corresponded to greater emergence activity. Emergence activity and minimum colony size were not related to spacing between bars or time since grating, indicating rapid habituation by R. megaphyllus. However, circling at grates continued for many years and bentwing bats (Miniopterus spp.) made little use of these sites. Bat-friendly grates appear to be an effective management option for R. megaphyllus , but alternatives need to be trialled for other species. Derelict mines can provide habitat for cave-roosting bats but are often grated to prevent human access, with little known about the long-term responses of bats. We assessed the long-term effects of grating on bats and found that although there was rapid habituation to grated mines, altered flight behaviour was present decades after grating and there was little use of these sites by threatened species. This suggests that alternative management of derelict mines is required to conserve threatened bat roosting habitat. Photo by Leroy Gonsalves. [ABSTRACT FROM AUTHOR]

Semi‐arid and arid landscapes (dry‐lands) cover 41% of the Earth's land surface over five continents. These areas are home to 55% of mammal species. Bats have the second highest species richness among mammals, and, although many species are adapted to arid conditions, they are particularly sensitive in these habitats and require conservation priority.Information on bats in arid and semi‐arid landscapes is scattered, patchy and focused on small‐scale studies; therefore, we undertook a systematic review using the PRISMA protocol to identify the current knowledge status, detect knowledge gaps and propose future research priorities.We analysed 346 published articles and evaluated 40 topics within five topic categories (taxa studied, methodologies used, biology, ecology and conservation). The most commonly studied topic categories were ecology and biology. However, we found a gap in the topic category conservation (including topics such as conservation status and roost conservation). Our network analysis of topics within the categories showed that most ecology papers were focused on distribution, species richness and habitat use.When we analysed keywords, we found that phylogeny, taxonomy and distribution demonstrated relatively high presence. Moreover, comparison of the percentage of studies conducted in dry‐lands and the percentage of land surface area covered by dry‐lands in the continents revealed that dry‐lands in Africa and Australia were especially under‐represented. Our review shows that knowledge of bats in semi‐arid and arid landscapes is biased towards new records of the distribution of species, as well as covering systematic/taxonomic and morphological aspects of bat biology.We suggest that research on conservation measures and guidelines to protect the bat species found in semi‐arid and arid landscapes should be prioritised, together with the sharing of knowledge with local practitioners and the development of citizen science programmes. [ABSTRACT FROM AUTHOR]

Bat boxes are frequently used as conservation and habitat-offset measures, yet their effectiveness is equivocal, particularly in Australia. Boxes used in Australia are largely voluminous-type boxes with Chalinolobus gouldii (Gould's wattled bat) frequently dominating their use. We tested multichambered boxes comprising fissure-type cavities made from either plywood (~20 000 cm3) or woodcement (~7400 cm3). We investigated whether occupancy was influenced by box colour (white boxes facing morning sun versus black boxes facing afternoon sun), box material/size, chamber width (15 mm versus 20 mm) and box host (tree versus pole). Boxes were monitored over 1.8 years. Overall, 245 bat observations were recorded. Boxes were frequently used (15% of 1088 box checks) by Nyctophilus geoffroyi (lesser long-eared bat), a species uncommonly reported to use boxes, which used 50 of the 64 boxes (78%), including for maternity roosting (n = 6). In comparison, C. gouldii was rarely detected (1% of box checks). Two other species were also found in boxes at low frequencies. Modelling showed a preference by N. geoffroyi for black boxes, the larger plywood box and boxes installed on poles. Fissure-type boxes appear to meet the roost requirements of N. geoffroyi but not that of C. gouldii , the species principally detected in voluminous-type boxes and postulated to gain a competitive advantage. The black woodcement box was the second most frequently used design, demonstrating that this long-lasting box material can be a suitable alternative to the less durable plywood material. Given that just one species commonly used boxes, there is a need for further research on box designs. The frequent use of bat boxes as conservation and habitat-offset tools has outpaced the research required to implement bat box programs effectively. We tested narrow-chambered boxes. These boxes were attractive for Nyctophilus geoffroyi (lesser long-eared bat) but not for Chalinalobus gouldii (Gould's wattled bat), a species postulated to gain a competitive advantage where voluminous-type boxes are installed. N. geoffroyi showed a preference for warm boxes and the plywood box. Given that just one species commonly used the tested boxes, there is a need for further research on box designs. [ABSTRACT FROM AUTHOR]

Australia's 81 bat species play vital ecological and economic roles via suppression of insect pests and maintenance of native forests through pollination and seed dispersal. Bats also host a wide diversity of coronaviruses globally, including several viral species that are closely related to SARS-CoV-2 and other emergent human respiratory coronaviruses. Although there are hundreds of studies of bat coronaviruses globally, there are only three studies of bat coronaviruses in Australian bat species, and no systematic studies of drivers of shedding. These limited studies have identified two betacoronaviruses and seven alphacoronaviruses, but less than half of Australian species are included in these studies and further research is therefore needed. There is no current evidence of spillover of coronaviruses from bats to humans in Australia, either directly or indirectly via intermediate hosts. The limited available data are inadequate to determine whether this lack of evidence indicates that spillover does not occur or occurs but is undetected. Conversely, multiple international agencies have flagged the potential transmission of human coronaviruses (including SARS CoV-2) from humans to bats, and the consequent threat to bat conservation and human health. Australia has a long history of bat research across a broad range of ecological and associated disciplines, as well as expertise in viral spillover from bats. This strong foundation is an ideal platform for developing integrative approaches to understanding bat health and sustainable protection of human health. [ABSTRACT FROM AUTHOR]

Bat boxes are often used as a conservation tool in human-disturbed landscapes across Australia; however, to assess their effectiveness we need to understand the factors influencing their occupancy by insectivorous bats. We investigated roost selection by Gould's wattled bat (Chalinolobus gouldii) using 76 bat boxes, comprising six designs, across three sites in suburban Melbourne, Australia. We conducted monthly surveys for a year and recorded the physical characteristics of each box. Five species of bats were recorded but Gould's wattled bats dominated box occupancy year-round at all three sites. Group sizes ranged from 1 to 58 individuals, with maternity colonies forming over summer. There was little consistency in the use of selection criteria by Gould's wattled bats when choosing a bat box as a day roost, with considerable variability across sites and seasons, highlighting the flexibility in roost site selection by this widespread, adaptable species. Our findings show that bat boxes can be an effective tool for providing supplementary roosts for Gould's wattled bats in urbanised landscapes. However, little is known about the impact on the whole bat community, especially disturbance-sensitive taxa, of artificially increasing roosting resources for common species. [ABSTRACT FROM AUTHOR]

Fire is notably becoming more intense, frequent and widespread due to climate change. In northern Australia, inappropriate fire regimes have been implicated in mammal declines, yet nothing is known about how different aspects of fire regimes affect bats in this region. This study aimed to determine how fire intensity, associated with seasonality, affects insectivorous bats on a local scale. An experimental M BACI approach was used on five site replicates across Cape York Peninsula, where ultrasonic detectors were used to determine the activity of insectivorous bats in response to low intensity burns (LIBs) and high intensity burns (HIBs) on a local scale. Total bat activity increased due to LIBs, but showed no response to HIBs. Activity of edge-open guild bats also increased due to LIBs but decreased in response to HIBs. Activity of open guild bats was unaffected by LIBs, but exhibited a strong positive response to HIBs. Activity of closed guild bats showed no response to fire, or fire intensity. Responses were likely derived from changes in habitat structure and prey availability. Given that each bat guild responded differently to each fire intensity, this lends support to the 'pyrodiversity begets biodiversity' concept, which is currently the basis for many fire management practices for conservation in northern Australia. [ABSTRACT FROM AUTHOR]

Microbats perform important ecological services in agro-ecosystems, but several species are globally threatened by loss of roosting and breeding habitats. The successful conservation of bats in agricultural land requires adequate knowledge of their ecology. Using ultrasonic recorders, we studied the activity of insectivorous bats in areas of macadamia production in eastern Australia at two spatial scales: across woodland-orchard transects at the local scale and across three levels of fragmentation at the landscape scale. At the local scale, activity patterns of 'clutter' and 'edge' specialists were consistently higher in woodland patches, gradually decreasing towards isolated orchards, where only a few 'open' specialists were active. At the landscape scale, bat community activity was affected by the level of fragmentation, partly because three of the most recorded taxa ( Austronomus australis, Saccolaimus flaviventris and Miniopterus australis) had their highest activity in less-fragmented areas. A distance-based model explained 24% of the bat community activity based on a combination of six environmental variables. Canonical correspondence analysis showed that a number of bat taxa were associated with open areas of macadamia, whereas other taxa were associated with increasing values of landscape composition, and arthropod and water availability. In addition, total bat activity was highly correlated with foraging rate. These results suggest that most bat taxa were influenced by proximity to woodland and the degree of fragmentation, and only few taxa were able to exploit isolated orchards. Environmental factors that promote bat activity could be exploited to strengthen conservation efforts. Preserving remnant woodland and promoting habitat heterogeneity will benefit several bat species. In particular, the foraging activity of 'edge' specialists could be fostered by increasing landscape connectivity and maintaining unobstructed water bodies near macadamia orchards. Considering that bats forage as they navigate these areas, conservation efforts could also bring benefits to farmers through pest-reduction services. [ABSTRACT FROM AUTHOR]

Habitat modelling and predictive mapping are important tools for conservation planning, particularly for lesser known species such as many insectivorous bats. However, the scale at which modelling is undertaken can affect the predictive accuracy and restrict the use of the model at different scales. We assessed the validity of existing regional-scale habitat models at a local-scale and contrasted the habitat use of two morphologically similar species with differing conservation status (Mormopterus norfolkensis and Mormopterus species 2). We used negative binomial generalised linear models created from indices of activity and environmental variables collected from systematic acoustic surveys. We found that habitat type (based on vegetation community) best explained activity of both species, which were more active in floodplain areas, with most foraging activity recorded in the freshwater wetland habitat type. The threatened M. norfolkensis avoided urban areas, which contrasts with M. species 2 which occurred frequently in urban bushland. We found that the broad habitat types predicted from local-scale models were generally consistent with those from regional-scale models. However, threshold-dependent accuracy measures indicated a poor fit and we advise caution be applied when using the regional models at a fine scale, particularly when the consequences of false negatives or positives are severe. Additionally, our study illustrates that habitat type classifications can be important predictors and we suggest they are more practical for conservation than complex combinations of raw variables, as they are easily communicated to land managers. [ABSTRACT FROM AUTHOR]

Australian bat lyssavirus (ABLV) was first described in 1996 and has been regularly detected in Australian bats since that time. While the virus does not cause population level impacts in bats and has minimal impacts on domestic animals, it does pose a public health risk. For this reason, bats are monitored for ABLV and a national dataset is collated and maintained by Wildlife Health Australia. The 2010–2016 dataset was analysed using logistic regression and time-series analysis to identify predictors of infection status in bats and the factors associated with human exposure to bats. In common with previous passive surveillance studies, we found that little red flying-foxes (Pteropus scapulatus) are more likely than other species to be infected with ABLV. In the four Australian mainland species of flying-fox, there are seasonal differences in infection risk that may be associated with reproductive cycles, with summer and autumn the seasons of greatest risk. The risk of human contact was also seasonal, with lower risk in winter. In line with other studies, we found that the circumstances in which the bat is encountered, such as exhibiting abnormal behaviour or being grounded, are risk factors for ABLV infection and human contact and should continue be key components of public health messaging. We also found evidence of biased recording of some types of information, which made interpretation of some findings more challenging. Strengthening of "One Health" linkages between public health and animal health services at the operational level could help overcome these biases in future, and greater harmonisation nationally would increase the value of the dataset. [ABSTRACT FROM AUTHOR]