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Diverse species assemblages theoretically partition along multiple resource axes to maintain niche separation between all species. Temporal partitioning has received less attention than spatial or dietary partitioning but may facilitate niche separation when species overlap along other resource axes. We conducted a broad‐scale acoustic study of the diverse and heterogeneous Great Smoky Mountains National Park in the Appalachian Mountains. Between 2015 and 2016, we deployed acoustic bat detectors at 50 sites (for a total of 322 survey nights). We examined spatiotemporal patterns of bat activity (by phonic group: Low, Mid, and Myotis) to test the hypothesis that bats partition both space and time. Myotis and Low bats were the most spatially and temporally dissimilar, while Mid bats were more general in their resource use. Low bats were active in early successional openings or low‐elevation forests, near water, and early in the evening. Mid bats were similarly active in all land cover classes, regardless of distance from water, throughout the night. Myotis avoided early successional openings and were active in forested land cover classes, near water, and throughout the night. Myotis and Mid bats did not alter their spatial activity patterns from 2015 to 2016, while Low bats did. We observed disparate temporal activity peaks between phonic groups that varied between years and by land cover class. The temporal separation between phonic groups relaxed from 2015 to 2016, possibly related to changes in the relative abundance of bats or changes in insect abundance or diversity. Temporal separation was more pronounced in the land cover classes that saw greater overall bat activity. These findings support the hypothesis that niche separation in diverse assemblages may occur along multiple resource axes and adds to the growing body of evidence that bats partition their temporal activity. [ABSTRACT FROM AUTHOR]

Context: Fire transforms, fragments and sometimes maintains forests, creating mosaics of burned and unburned patches. Highly mobile animals respond to resources in the landscape at a variety of spatial scales, yet we know little about their landscape-scale relationships with fire. Objectives: We aimed to identify drivers of bat richness in a landscape mosaic of forested and burned areas while identifying spatial scales at which bat richness was most strongly related to extent, configuration, and diversity measures of landscape-level habitat. Methods: We used multi-species hierarchical occupancy modelling to relate bat richness to landscape variables at 10 spatial scales, based on acoustic data collected in the Sierra Nevada, United States. We also assessed redundancy among landscape variable type (extent, configuration, and diversity) and between focal patch types (forested and burned). Results: Bat richness was positively associated with heterogenous landscapes, shown by positive associations with pyrodiversity, extent and mean area of burned patches, burned and forested edge density and patch density and relationships were generally consistent across scales. Extent of forest cover and burned areas were highly correlated, but configuration and diversity of these patch types diverged. Conclusions: Bat communities of our study area appear to be largely resilient to wildfire and adapted to more heterogenous forests and shorter-interval fire regimes that likely predominated before the fire suppression era. [ABSTRACT FROM AUTHOR]

Wildfires are increasing in incidence and severity across coniferous forests of the western United States, leading to changes in forest structure and wildlife habitats. Knowledge of how species respond to fire‐driven habitat changes in these landscapes is limited and generally disconnected from our understanding of adaptations that underpin responses to fire.We aimed to investigate drivers of occupancy of a diverse bat community in a fire‐altered landscape, while identifying functional traits that underpinned these relationships.We recorded bats acoustically at 83 sites (n = 249 recording nights) across the Plumas National Forest in the northern Sierra Nevada over 3 summers (2015–2017). We investigated relationships between fire regime, physiographic variables, forest structure and probability of bat occupancy for nine frequently detected species. We used fourth‐corner regression and RLQ analysis to identify ecomorphological traits driving species–environment relationships across 17 bat species. Traits included body mass; call frequency, bandwidth, and duration; and foraging strategy based on vegetation structure (open, edge, or clutter).Relationships between bat traits and fire regime were underpinned by adaptations to diverse forest structure. Bats with traits adapting them to foraging in open habitats, including emitting longer duration and narrow bandwidth calls, were associated with higher severity and more frequent fires, whereas bats with traits consistent with clutter tolerance were negatively associated with fire frequency and burn severity. Relationships between edge‐adapted bat species and fire were variable and may be influenced by prey preference or habitat configuration at a landscape scale.Predicted increases in fire frequency and severity in western US coniferous forests are likely to shift dominance in the bat community to open‐adapted species and those able to exploit postfire resource pulses (aquatic insects, beetles, and snags). Managing for pyrodiversity within the western United States is likely important for maintaining bat community diversity, as well as diversity of other biotic communities. [ABSTRACT FROM AUTHOR]

Context. Multi-use management of global forests has seen even-aged, high-stem density regrowth represent >50% of the world's forest cover. Large areas of river red gum (Eucalyptus camaldulensis) forests have declined in ecological condition. Thinning has been promoted as a tool to reduce competition in dense, young stands of E. camaldulensis regrowth, yet responses of forest structure and fauna to large-scale thinning are largely unclear. Aims. To establish a before-after-control-impact experiment to assess responses of forest structure and fauna to large-scale (compartment-level; ~440 ha) silvicultural thinning. Methods. We measured immediate (<2 yrs) responses of forest structural components (living, dead and hollow-bearing stem densities, coarse woody debris (CWD) density and volumes and ground cover) and components of biodiversity (bats, birds, volant insects and non-volant mammals) before and after thinning within five control and three impact compartments. Key results. Thinning reduced stem density by approximately two-thirds and was associated with a substantial increase in activity and richness of bats and a change in bat species composition. There was no change in richness for birds and non-volant mammals, nor insect biomass in relation to thinning. However, thinning affected composition of non-volant mammals, with the common brushtail possum (Trichosurus vulpecula) and red fox (Vulpes vulpes) less active postthinning at impact plots relative to control plots. Thinning reduced the density of dead stems, though these were predominantly small (~13 cm diameter at breast height over bark, or dbhob) and mostly lacked hollows. Hollowbearing tree density was not affected by thinning. Although thinning increased CWD densities, volume of CWD did not change, indicating that thinning contributed small-sized CWD. Thinning did not affect densities of hollow- and fissure-bearing CWD or ground cover, which was low (<7%) in control and impact plots. There were no other negative effects on biodiversity detected. Conclusions. Short-term fauna responses to thinning were generally neutral or positive. Implications. Ongoing monitoring is required to detect long-term changes that may result from colonisation or altered breeding success after thinning. We recommend that some unthinned stands should be retained throughout the landscape to provide a mosaic forest structure suitable for a diverse fauna. [ABSTRACT FROM AUTHOR]

Over half of the world's forests are secondary regrowth and support considerable biodiversity. Thinning of these forests is a widespread management practice that can affect forest species, including echolocating bats and their prey., We compared total activity of 11 bat taxa, foraging activity of six bat guilds and biomass of 11 insect orders across four forest thinning categories in managed remnant eucalypt forests in south-eastern Australia: unthinned regrowth, forest thinned recently (0-4 years) and in the medium term (5-10 years) and reference (mature open forest). Thinning had been carried out at large (˜350 ha) spatial scales., Total bat activity was 60% less and foraging activity was 80% less in unthinned regrowth, compared to reference sites, but activity levels were similar among thinned and reference sites. Insect biomass was greatest in unthinned sites, and while bat activity was related to prey biomass, this relationship was weak in unthinned sites. Together, this suggests that forest structure was more important than prey availability or time since thinning in influencing bat activity patterns., Synthesizing our findings with the broader literature on bats and thinning, we found support for a clutter threshold of 1100 stems ha−1, above which bat activity was markedly lower, across two continents (the USA and Australia) and four broad vegetation types (eucalypt, conifer, deciduous and mixed forests)., While elsewhere bats with adaptive traits for open habitats generally respond positively to thinning, in our study, species with traits consistent with clutter tolerance (high call frequency and low wing aspect ratio) had lowest activity levels (up to 22 times) in unthinned regrowth compared to all other forest types., Synthesis and applications. Widespread dense regrowth forest can restrict movement and foraging of bats, even those adapted to clutter. We recommend thinning dense regrowth or plantations to below 1100 stems ha−1 when targeting bat foraging habitat, but effects of thinning on roost habitat and other forest biota require further investigation. [ABSTRACT FROM AUTHOR]

Coastal lagoons provide key habitat for a wide range of biota but are often degraded by intense urbanization pressures. Insectivorous bats use these highly productive ecosystems and are likely to be impacted by their decline in quality. We compared bat activity and richness and invertebrate biomass and richness across a gradient of lagoon quality (9 lagoons) in the Greater Sydney region, Australia to determine the extent to which bats and their prey were impacted by lagoon degradation. Bats were more diverse and 19 times more active at higher quality lagoons. The trawling bat, Myotis macropus , was absent from all low quality lagoons, but these lagoons were used by other species such as Miniopterus schreibersii oceanensis . Invertebrate richness and biomass did not differ significantly across lagoon quality. We examined potential mechanisms of insectivorous bat decline at degraded lagoons by measuring toxic metal concentrations in bat fur, invertebrates and sediment. Lead and zinc were detected at environmentally significant levels in the sediments of lower quality lagoons. Furthermore, lead concentrations were 6 times the lowest observable adverse effects level for small mammals in the hair of one individual M. macropus . The present study demonstrates that coastal lagoons support a rich bat community, but ongoing development and pollution of these habitats is likely to negatively impact on insectivorous bat species, especially trawling species. [ABSTRACT FROM AUTHOR]