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Roost selection and diet are fundamentally important to bats and can vary geographically and with habitat. The greater broad-nosed bat (Scoteanax rueppellii) is infrequently captured and poorly known, meaning appropriate conservation actions are difficult to determine. To assess variation across different habitats, we collected faecal samples for dietary analysis and radio-tracked individuals to identify roost trees at four different sites across New South Wales, Australia. Analysis of droppings verified beetles as the main prey in each study area except one dominated by mangroves, and confirmed for the first time carnivory in wild-caught individuals from the presence of hair from other bat species in its droppings. Very large, hollow trees were used as maternity roosts, being typically larger than neighbouring trees. Roosting habitat varied from wet sclerophyll forest in gullies to old-growth mangroves, and tree species used as roosts also varied. Colony size at maternity roosts was often 50–100 bats and fidelity to the maternity roost varied, with some being switched almost daily and others occupied for at least several days. One maternity roost was re-used 2 years later. Both the importance of beetles in the diet and roosts located in more productive landscapes suggest coastal plains and foothills may represent key habitat. Understanding a species' ecology across different geographic regions provides a sound basis for improving its conservation. Greater broad-nosed bats were captured and radio-tracked in different regions to describe roosts used and diet. Beetles were the main prey in each study area except one dominated by mangroves, and for the first time carnivory in wild-caught individuals was documented. Very large, hollow trees were used as maternity roosts, but vegetation associations and tree species varied. [ABSTRACT FROM AUTHOR]

Aim: Mega‐fires are predicted to increase with climate change. Australia experienced the largest ever documented forest fires in 2019–2020, but the response of most taxa remains poorly known. We used acoustic arrays to estimate impact of the mega‐fires on the density of an iconic marsupial. Location: North‐east New South Wales, Australia. Time period: Pre‐fire density estimated in 2018–2019 and post‐fire density in 2019–2020. Major taxa studied: Koala, Phascolarctos cinereus. Methods: We estimated male density before and after fires using large acoustic arrays and spatial count models. Acoustic arrays sampled three timber production forests with a gradient in fire severity and three unburnt controls in national parks. Results: Koalas were temporarily extirpated where high fire severity dominated the landscape, but some localized recovery was evident after 1 year. Where moderate severity fire dominated, density was reduced by about 50% within 1 year, but koalas were widespread throughout the burnt area. In our third area dominated by low severity fire, no impact was detected as pre‐ and post‐fire uncertainty intervals overlapped. Control sites surveyed at similar times showed little change in density between years. There was no relationship between pyrodiversity and koala density. Within arrays broadly dominated by moderate or high severity fire, density 1 year after fire was lower in burnt patches of both low and high severity fire. Regionally, 9.8% of landscape samples (2 km × 2 km) in koala habitat were dominated by high fire severity, while a further 6.1% were dominated by moderate fire severity, suggesting c. 13% decline in koala density. Main conclusions: A substantial impact of high severity fire was confirmed. Severe impacts were localized across the landscape, recovery had begun within a year and resilience was evident where low severity fire dominated. However, more frequent fires in the future will compound koala losses. [ABSTRACT FROM AUTHOR]

The compatibility of forestry and koala conservation is a controversial issue. We used a BACIPS design to assess change in koala density after selective harvesting with regulations to protect environmental values. We also assessed additional sites heavily harvested 5–10 years previously, now dominated by young regeneration. We used replicate arrays of acoustic sensors and spatial count modelling of male bellowing to estimate male koala density over 3600 ha. Paired sites in nearby National Parks served as controls. Naïve occupancy was close to 100% before and after harvesting, indicating koalas were widespread across all arrays. Average density was higher than expected for forests in NSW, varying between arrays from 0.03–0.08 males ha−1. There was no significant effect of selective harvesting on density and little change evident between years. Density 5–10 years after previous heavy harvesting was equivalent to controls, with one harvested array supporting the second highest density in the study. Within arrays, density was similar between areas mapped as selectively harvested or excluded from harvest. Density was also high in young regeneration 5–10 years after heavy harvesting. We conclude that native forestry regulations provided sufficient habitat for koalas to maintain their density, both immediately after selective harvesting and 5–10 years after heavy harvesting. [ABSTRACT FROM AUTHOR]

Forests on private land have a wide range of uses that span activities such as recreation, primary production and nature conservation. Traditionally, it has been difficult for researchers to access private land to undertake systematic surveys. We used mini‐acoustic sensors (Audiomoth) mailed via the postal service to overcome landholder concerns about researchers accessing private property, with a focus on properties used for private native forestry.We surveyed koalas, an iconic threatened marsupial, in north‐east New South Wales, Australia using passive acoustics, with repeat surveys over consecutive nights to account for imperfect detection in an occupancy modelling framework.Over 3 years, we surveyed 128 sites and recorded 2,560 male bellows. Detection probability over seven nights was high (>0.79), but varied substantially between years, due to use of different sensors, housings and weather conditions. After accounting for detection probability, modelling revealed that koalas commonly occupied private native forests of the study region (probability of occupancy = 0.58 ± 0.08).Occupancy was modelled against several covariates and it varied with the landscape extent of sealed roads (₋ve), NDVI (₋ve) and a habitat suitability model (+ve, but minor). There was no support for occupancy in private forests to be related to a range of other factors including extent of surrounding cleared land, timber harvesting history, fire and other measured habitat features.Synthesis and applications. We conclude that mini‐acoustic recorders mailed to landholders were a highly effective method for assessing koala occupancy, after accounting for variable detection, and the approach could be deployed more widely for a range of species. Private native forests in partly cleared landscapes are commonly occupied by koalas, highlighting that this tenure is crucial for koala conservation and that practices seeking to balance conservation and production should be encouraged. In addition to sensitive habitat management in private forests, sealed road density is a major threat needing to be addressed. [ABSTRACT FROM AUTHOR]

The need to develop effective management strategies for insectivorous bat populations requires an understanding of factors influencing habitat use. Availability of pest prey, such as mosquitoes is likely to be one such factor. To assess whether this is the case, we radio-tracked Vespadelus vulturnus Thomas (little forest bat), a predator of Aedes vigilax Skuse (saltmarsh mosquito), in saltmarsh and adjacent coastal swamp forest during periods of high and low Ae. vigilax abundance. When mosquito abundance in structurally-open saltmarsh was similar to the more cluttered coastal swamp forest, use of saltmarsh by V. vulturnus was disproportionately greater than its availability, with saltmarsh selected preferentially for foraging. However, at times of low Ae. vigilax abundance in saltmarsh, use of saltmarsh by V. vulturnus was reduced and all habitats were used in proportion to availability in the study area. This is the first radio-tracking study to demonstrate a shift in foraging range by an insectivorous bat species correlated with fluctuations in the distribution and abundance of a particular prey resource. The shift in foraging range by V. vulturnus, corresponding with a spatio-temporal variation in abundance of Ae. vigilax highlights the importance of mosquitoes as a dietary item. Broadscale pest control of Ae. vigilax may have ecological implications for the diet and habitat use of V. vulturnus. An adaptive management approach is proposed, whereby careful monitoring of insectivorous bat populations is recommended before and after any application of broadscale mosquito control measures. We also suggest a precautionary approach is taken such that broadscale control of mosquitoes avoids the lactation period of bats, a time when their energetic demands are greatest and when there is reduced risk of contracting mosquito-borne diseases transmitted by Ae. vigilax.

Schemes designed to make farming landscapes less hostile to wildlife have been questioned because target taxa do not always respond in the expected manner. Microbats are often overlooked in this process, yet persist in agricultural landscapes and exert top-down control of crop pests. We investigated the relationship between microbats and measures commonly incorporated into agri-environment schemes, to derive management recommendations for their ongoing conservation. We used acoustic detectors to quantify bat species richness, activity, and feeding in 32 linear remnants and adjacent fields across an agricultural region of New South Wales, Australia. Nocturnal arthropods were simultaneously trapped using black-light traps. We recorded 91,969 bat calls, 17,277 of which could be attributed to one of the 13 taxa recorded, and 491 calls contained feeding buzzes. The linear remnants supported higher bat activity than the fields, but species richness and feeding activity did not significantly differ. We trapped a mean 87.6 g (±17.6 g SE) of arthropods per night, but found no differences in biomass between land uses. Wider linear remnants with intact native vegetation supported more bat species, as did those adjacent to unsealed, as opposed to sealed roads. Fields of unimproved native pastures, with more retained scattered trees and associated hollows and logs, supported the greatest bat species richness and activity. We conclude that the juxtaposition of linear remnants of intact vegetation and scattered trees in fields, coupled with less-intensive land uses such as unimproved pastures will benefit bat communities in agricultural landscapes, and should be incorporated into agri-environment schemes. In contrast, sealed roads may act as a deterrent. The "wildlife friendly farming" vs "land sparing" debate has so far primarily focussed on birds, but here we have found evidence that the integration of both approaches could particularly benefit bats.