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Context: Introduced predators pose a significant threat to biodiversity. Understanding how predators interact with other threats such as fire is crucial to developing effective conservation strategies. Aims: We investigated interactions between the greater bilby (Macrotis lagotis) and two introduced predators, the European red fox (Vulpes vulpes) and feral cat (Felis catus), in response to fire management in a remote part of the Tanami Desert, Australia. Methods: We used motion-sensor cameras and non-invasive genetic sampling to monitor bilbies and predators. We compared activity profiles to determine the level of temporal overlap among species, and used generalised linear modelling to assess the correlation between activity and average normalised difference vegetation index (NDVI; as a proxy for fire-associated environmental change). Finally, we used spatially explicit capture–recapture modelling to estimate cat and bilby densities before and after fire. Key results: Cat and bilby activity declined following fire, whereas fox activity increased (despite only a small proportion of the study area being burnt). Bilbies and foxes showed the greatest overlap in temporal activity (76%), followed by bilbies and cats (71%) and cats and foxes (68%). Bilbies and cats were more likely to be captured in areas with a lower NDVI, whereas foxes were more likely to be captured in areas with a higher NDVI. Bilby density declined significantly following fire, whereas cat density remained constant through time. Conclusions: Declines in bilby activity and density following fire may be attributed to emigration from the study area and/or increases in fox activity. Post-burn emigration could be due to wide scale destruction of important food resources. However, given much of the study area where bilbies were detected remained unburnt, it is more likely that observed declines are related to increases in fox activity and associated increases in predation pressure. Improved understanding may be gained by experimentally manipulating both fire and predator densities. Implications: Increases in fox activity following fire are likely to have devastating consequences for the local bilby population. It is thus vital that appropriate management activities are put in place to protect bilbies from foxes. This may be achieved through a combination of lethal control and indirect methods. Cats and foxes are a significant threat to bilbies, with their impacts likely to be worsened by fire. We used camera-traps and genetic sampling to investigate whether bilby–predator interactions changed in response to planned fire. We found a high level of overlap in activity among the three species, and a general decline in bilby and cat activity, and an increase in fox activity following fire. Our study indicated that broad-scale fire is likely to have negative consequences for bilby populations, most likely owing to an increase in fox predation pressure. Warlpiri : Minija manu pujumalu kalu-jana ngarni walpajirri kuja ka warlu-jangkalku karrimi (ngunjalparla/winingka). Ngulajangka yartiwajirli ka palka-mani kuna-wartirlki panu. Ngulajangka kanarlu-jana nyanyi kuyu-patu marnkurrpa minija, pujuma manu walpajirri yartiwajirla, wita-karri-karrirlki kalu nyinami walpajirri-watiji manu minija-watiji manu nganayiji pujumaju kalu panu nyinami nyampurla walyangkaju (ngurungkaju). Wiri-jarlu warluju ngulaju maju walpajirri-kiji. Pujumaju panu, punku walpajirri-kiji. The translation of this short summary from English to Warlpiri language was provided by Annette Patrick from the community of Lajamanu in the northern Tanami Desert. Warlpiri language is spoken by ~3000 of the Warlpiri people from the Tanami Desert, north-west of Alice Springs in central Australia. Photograph supplied by H.M. Geyle. This article belongs to the collection Indigenous and cross-cultural wildlife research in Australia. [ABSTRACT FROM AUTHOR]

While resource selection varies according to the scale and context of study, gathering data representative of multiple scales and contexts can be challenging especially when a species is small, elusive and threatened. We explored resource selection in a small, nocturnal, threatened species, the greater bilby, Macrotis lagotis , to test (1) which resources best predict bilby occupancy, and (2) whether responses are sex specific and/or vary over time. We tracked 20 bilbies and examined within home range resource selection over multiple seasons in a large (110 ha) fenced sanctuary in temperate Australia. We tested a set of plausible models for bilby resource selection, and found that food biomass (terrestrial and subterranean invertebrates and subterranean plants) and soil textures (% sand, clay and silt) best predicted bilby resource selection for all sampling periods. Selection was also sex specific: female resource use, relative to males, was more closely linked to the location of high-quality resources (invertebrate biomass). Bilby selection for roads was independent of season but varied over time with males selecting for areas closer to roads when plants increased in density off roads. Our findings demonstrate the importance of considering resource selection over multiple contexts and highlight a method to collect such data on a difficult to study, threatened species. Collecting such data is critical to understanding the habitat required by species. • We studied multiyear habitat selection by a small nocturnal marsupial. • Resource selection was sex specific and varied over time. • Females were more selective of high-quality resources. • A snapshot habitat selection study is often inadequate for conserving species. • Reintroductions can fill key knowledge gaps for data-deficient threatened species. [ABSTRACT FROM AUTHOR]

A novel Eimeria sp. from a captive‐bred bilby (Macrotis lagotis Reid, 1837) has been identified in Western Australia. The bilby was bred at the Kanyana Wildlife Rehabilitation Centre, Perth, as part of the National Bilby Recovery Plan. Oocysts (n = 31) irregular blunt ellipsoidal, 17–18 × 11–12 (17.2 × 11.3); length/width (L/W) ratio 1.4–1.5 (1.5). Wall bi‐layered, 0.8–1.0 (0.9) thick, outer layer smooth, c.2/3 of total thickness. Micropyle barely discernible. Oocyst residuum is absent, but 2–3 small polar granules are present. Sporocysts (n = 31) ovoidal, 7–8 × 5–6 (7.8 × 5.7); L/W ratio 1.3–1.4 (1.4). Stieda, sub‐Stieda and para‐Stieda bodies absent or indiscernible; sporocyst residuum present, usually as an irregular body consisting of numerous granules that appear to be membrane‐bound or sometimes diffuse among sporozoites. Sporozoites vermiform with a robust refractile body. Further molecular characterization was conducted on the sporulated oocysts. At the 18S locus, it sat in a large clade of the phylogenetic tree with two isolates of Eimeria angustus from quendas (Isoodon obesulus Shaw, 1797) and the Choleoeimeria spp. It shared the highest identity with E. angustus (KU248093) at 98.84%; at the COI gene locus, it was unique and most closely related to Choleoeimeria taggarti, which is hosted by another species of marsupial, the yellow‐footed antechinus (Antechinus flavipes flavipes), with 90.58% genetic similarity. Based on morphological and molecular data, this isolate is a new species and named as Choleoeimeria yangi n. sp. [ABSTRACT FROM AUTHOR]

Abstract A novel Eimeria sp. from a captive‐bred bilby (Macrotis lagotis Reid, 1837) has been identified in Western Australia. The bilby was bred at the Kanyana Wildlife Rehabilitation Centre, Perth, as part of the National Bilby Recovery Plan. Oocysts (n = 31) irregular blunt ellipsoidal, 17–18 × 11–12 (17.2 × 11.3); length/width (L/W) ratio 1.4–1.5 (1.5). Wall bi‐layered, 0.8–1.0 (0.9) thick, outer layer smooth, c.2/3 of total thickness. Micropyle barely discernible. Oocyst residuum is absent, but 2–3 small polar granules are present. Sporocysts (n = 31) ovoidal, 7–8 × 5–6 (7.8 × 5.7); L/W ratio 1.3–1.4 (1.4). Stieda, sub‐Stieda and para‐Stieda bodies absent or indiscernible; sporocyst residuum present, usually as an irregular body consisting of numerous granules that appear to be membrane‐bound or sometimes diffuse among sporozoites. Sporozoites vermiform with a robust refractile body. Further molecular characterization was conducted on the sporulated oocysts. At the 18S locus, it sat in a large clade of the phylogenetic tree with two isolates of Eimeria angustus from quendas (Isoodon obesulus Shaw, 1797) and the Choleoeimeria spp. It shared the highest identity with E. angustus (KU248093) at 98.84%; at the COI gene locus, it was unique and most closely related to Choleoeimeria taggarti, which is hosted by another species of marsupial, the yellow‐footed antechinus (Antechinus flavipes flavipes), with 90.58% genetic similarity. Based on morphological and molecular data, this isolate is a new species and named as Choleoeimeria yangi n. sp.

When a species' last strong foothold occurs on Country, empowering Indigenous-led actions under the collaborative management of culturally significant species is key to species persistence. We examine how Indigenous Australians are using Indigenous knowledge to save the greater bilby, a highly valued species to Indigenous and non-Indigenous Australians. [ABSTRACT FROM AUTHOR]

Microchip-reading devices provide an inexpensive and efficient means of passively detecting and monitoring wildlife reintroductions, particularly where intensive methods such as trapping and radio-tracking may be difficult or pose risk to animal welfare. We trialled the use of microchip-reading antennas for post-release monitoring of the survival of bilbies (Macrotis lagotis) for a reintroduction in south-west Queensland. The antennas detected 76% of the released captive-born bilbies (all microchipped) and 30% of the microchipped wild-born bilbies during the study period. Overall, the microchip-reading antennas greatly improved the rate of detection for bilbies in the enclosure compared to cage trapping alone. Of the 42 bilbies that were microchipped and had the potential to be recaptured in traps or detected on microchip readers, 33 were recorded from the combined approaches, with 20 bilbies recaptured in traps and 29 bilbies detected on the microchip readers. Antenna location/placement should be carefully considered in the context of the target species' home range size as it may affect the probability of animals encountering the antenna. Here we demonstrate the ability to use these microchip-reading antennas to passively monitor post-release survival in a remote location, just one of many potential applications for these devices in wildlife management and conservation. Microchip-reading devices can be used to collect data on animal movements, behaviour and survival. We combined the use of microchip-reading antennas with more traditional trapping methods to monitor the survival of greater bilbies (Macrotis lagotis) after their reintroduction to a fenced exclosure in remote south-west Queensland. Microchip-reading antennas greatly improved the chances of detecting both captive- and wild-born bilbies, which are typically considered a 'trap-shy' species. These antennas are relatively inexpensive with a wide range of potential applications in wildlife management and conservation. Photograph by Cassandra Arkinstall/Save the Bilby Fund. [ABSTRACT FROM AUTHOR]

Remnant natural populations of greater bilbies (Macrotis lagotis) are confined to the Australian arid zone where bilbies construct and shelter in multiple burrows within their home range. We investigated burrow use behaviour of bilbies in a translocated population in temperate southern Australia to determine if behaviour differed in this climatic zone. Over a 12 month period, 43 adult bilbies at Venus Bay Conservation Park were spool-and-line tracked to 118 burrows. Active burrow density was 0.55 per ha, and bilbies at the site used multiple burrows (up to 13 for males and 8 for females) and regularly moved between diurnal burrows. Male bilbies had significantly larger burrow ranges (10.2 ± 5.8 ha, MCP100, mean ± s.d.) than females (2.6 ± 1.8 ha), and were similar in size to those recorded in an arid zone population. Males' burrow ranges tended to overlap with the burrow range of multiple other males and females. The density of burrows in the current study suggests that bilby burrows were likely to have been a common landscape feature within the southern parts of the species range prior to their local extinction. Further research is needed to determine the impact of the loss of bilby burrows from southern Australia on other burrow commensal species. We describe burrow use behaviour in greater bilbies exposed to a temperate climate for the first time using a translocated population in southern South Australia. Bilbies in our study used multiple burrows within their home range, regularly moved between diurnal burrows and male bilbies had larger burrow ranges with more overlap than did females. Burrow density was 2.75–5.0 times the density of bilbies at the site, indicating that burrows were likely a common landscape feature in areas where bilbies were once in high density. Photograph by Karleah Berris. [ABSTRACT FROM AUTHOR]

The ecological role of canids in arid Australia is unresolved. Some argue they play a role regulating populations of herbivores and introduced mesopredators such as feral cats (Felis catus) and foxes (Vulpes vulpes). However, evidence also suggests they pose a threat to native species populations. The aims of this study were to determine the extent of canid predation on the bilby population at Astrebla Downs National Park, Queensland, to improve our understanding of the ecological role that canids serve in the park and to determine whether seasonal changes in the canid diet can be used to predict if and when management should intervene. Canid scats (n = 723) were collected over seven years and their content examined. The percentage of bilby remains in the canid scats varied from 13 to 85% (mean = 43%) and was 20-100% by volume. In total, 23 vertebrate species were identified in canid scats. The percentage of cat remains was 0-44% (mean = 11%), peaking in 2013 during a cat plague and coinciding with canids actively hunting cats. Fox remains were not detected in dog scats. These results indicate that canids had a varied diet and at times threatened the bilby population at Astrebla. [ABSTRACT FROM AUTHOR]

Captive breeding and translocation, whereby selected individuals are used to supplement or re‐establish failing populations, are powerful tools for conserving threatened fauna. These tools, however, are rarely successful at establishing self‐sustaining populations that can survive without ongoing human assistance. The maintenance of genetic diversity and demographic security in captivity, or following wildlife translocation events, is important for improving the long‐term effectiveness of threatened species recovery efforts around the world. Routine population monitoring using hypervariable genetic markers represents a promising technique for evaluating the effect of established management practices on population structure and genetic diversity across various spatial and temporal scales. In this study, we employed a data set of 1,068 single nucleotide polymorphisms to conduct a comprehensive survey of population structure and genetic diversity in greater bilbies (Macrotis lagotis) held at 13 zoos and wildlife sanctuaries across Australia between August 1996 and December 2016. We observed significant genetic structuring across the study sites, consistent with the limited exchange of animals between independently managed facilities. The majority of variation, however, still occurred at the level of individual bilbies (75%, P < 0.001). We also uncovered evidence for an ongoing loss of genetic diversity in some conservation‐fenced populations, despite a slight excess of heterozygosity across the sampling sites as a whole. Maintaining the genetic health of bilbies in captivity or following translocation will therefore require stakeholders to focus on reducing individual mortality, and maintaining genetic connectivity across all existing populations through the regular exchange of selected individuals. As such, admixture is expected to play an increasingly important role in future conservation programs. © 2019 The Authors. Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. We evaluated the effect of different management strategies on the retention of genetic diversity in captive and fenced predator‐free bilby populations. Recurrent, low‐level immigration over a number of generations was the most successful strategy for introducing novel genetic variation into recently established colonies, successfully offsetting many of the issues associated with small population sizes (e.g., inbreeding and genetic drift). [ABSTRACT FROM AUTHOR]

Peramelemorphians (bandicoots and bilbies) are a unique and diverse group of digging Australasian marsupials, but their behavioral neurology and neuroanatomy is poorly known. Here, we have used Magnetic Resonance Imaging (MRI) to study the brains of three peramelemorphians: two bandicoots (Perameles nasuta and Isoodon obesulus) and the bilby (Macrotis lagotis), which is endangered. These brains had been stored in formaldehyde solution for more than 80 years and one of our goals was to demonstrate the feasibilty of extracting detailed comparative neuroanatomical information from the long-term preserved brains of rare, endangered, and extinct animals. High resolution anatomical and Diffusion Tensor Imaging was performed using a 9.4-T Bruker BioSpec 94/20 Avance III MRI system (Bruker, Ettlingen, Germany) located at the UNSW in Sydney. We were able to differentiate areal and laminar topography within isocortical areas (primary somatosensory – S1; and visual - V1, V2), as well as subdivisions within olfactory and limbic allocortical regions (cingulate, hippocampal). Resolution of subcortical structures was sufficient to differentiate α and β segments within the visual nucleus of the thalamus. We identified several previously unrecognized longitudinal association fiber systems as well as a rich array of sensory thalamocortical connections. Dense fiber pathways were observed to S1 and in the midbrain auditory pathways (mainly the lateral lemniscus, but also the brachium of the inferior colliculus). Our findings demonstrate the feasibility of using this sort of imaging of archived brains to analyze the neuroanatomy of rare and evolutionarily significant species and to relate these findings to the behavioral neurology of those species. [ABSTRACT FROM AUTHOR]

Ecosystem engineers are species that have a role in creating and maintaining certain habitat traits that are important for other species. Burrowing species do this by creating subterranean refugia from predation and thermal extremes, but also providing foraging opportunities through soil movement and by increasing local landscape heterogeneity. In this study, we used camera traps to monitor the burrows of greater bilbies (Macrotis lagotis), a vulnerable Australian marsupial, in an area subject to frequent disturbance by fire. We tested the hypothesis that bilby burrows provide refuge for other species and therefore their presence increases biodiversity. In total, 45 taxa – 22 bird, 16 reptile and 7 mammal taxa – were recorded interacting with 127 burrows across 7 sites. Species richness was greater at burrows compared with vegetation away from burrows, while abundance was no different. There was no difference in species assemblage for bilby burrows that were actively maintained by bilbies compared with abandoned burrows, although there was more activity at bilby maintained burrows. A wildfire allowed us to test the ad hoc hypothesis that the use of bilby burrows was greater when vegetation cover was removed by fire. We recorded significant differences in species assemblage interacting with burrows after fire, although overall species richness and abundance did not change. The response of individual species was variable; for example, burrows provide a refuge for smaller species (such as mice and small reptiles), and may therefore protect them from the effects of fire. Where they persist, bilbies provide an important ecosystem engineering service, as their burrows support a broad range of species. Further reduction in the distribution of the bilby is therefore likely to have a flow‐on effect on biodiversity, impacting species that use their burrows for refuge. [ABSTRACT FROM AUTHOR]

A male bilby (Macrotis lagotis) was presented to the Murdoch University Veterinary Anatomical Pathology Service following humane destruction due to severe lethargy. The bilby was emaciated with a focal ulcerated skin lesion on the dorsal tail base. Multifocal to coalescing foci of pyogranulomatous and often necrotizing inflammation was present within multiple organs, including the tail wound, adrenal glands, kidneys, lungs, brain, testes, lymph nodes, heart, liver, spleen and salivary glands. Admixed were abundant intrahistiocytic and extracellular pleomorphic yeast (round, oval and cigar-shaped) up to 6 μm diameter, often with a thin clear halo and occasional narrow-based budding. The diagnosis of disseminated sporotrichosis was confirmed via culture and sequencing of the internal transcribed spacer region of the causative agent, Sporothrix schenckii sensu lato. The route of entry of infection was considered most likely to have been via cutaneous inoculation of the tail base wound. To the authors' knowledge, this report describes the first known case of sporotrichosis in a native Australian animal. [ABSTRACT FROM AUTHOR]

The recognition of sign such as tracks, scats, diggings or burrows is widely used to detect rare or elusive species. We describe the type of sign that can be used to confirm the presence of the greater bilby (Macrotis lagotis) in comparison with sign that should be used only to flag potential presence. Clear track imprints of the front and hind feet, diggings at the base of plants to extract root-dwelling larvae, and scats commonly found at diggings can be used individually, or in combination, to verify presence, whereas track gait pattern, diggings in the open, and burrows should be used to flag potential bilby activity but not to verify presence. A protocol to assess potential activity and verify bilby presence is provided. We provide advice on the application of a plot-based technique to systematically search for sign and produce data for the estimation of regional occupancy. Digging and burrow activity can be readily detected from the air but systematic ground-based assessment to determine the rate of false-presence and false-absence needs to accompany aerial survey. The approach to estimate survey effort to assert bilby absence is also described. [ABSTRACT FROM AUTHOR]

A traditional design-reliant estimate of abundance is calculated by multiplying a density estimate obtained from transects to reflect the size of the study area. This type of estimate tells nothing about the nature of a species' distribution between the samples. In contrast, model-based inference can better estimate abundance by interpolating transect estimates over the study area with the aid of covariates. This study used density surface modelling (DSM) to predict spatial distribution of greater bilby (Macrotis lagotis) and rabbit (Oryctolagus cuniculus) pellets within a predator-proof enclosure at Currawinya National Park, south-west Queensland. Pellets and latrines were counted using distance sampling and plot sampling on 30 PPBio plots during 2012 and 2014. Pellets and latrines were not strongly associated with habitat features, reflecting the generalist nature of both species. Bilby pellets were found on 23 plots in 2012 and 5 plots in 2014. Rabbit pellets were present on 29 plots in 2012 and 16 plots during 2014. These substantial declines in pellet abundances coincided with invasion of the feral cat (Felis catus) into the enclosure. While DSM modelling can allow managers to make informed decisions about applying survey effort or management practices, it is not suited to all species or situations. [ABSTRACT FROM AUTHOR]

Greater bilbies (Macrotis lagotis) have been described as ecosystem engineers and their burrows are significant structures across an often featureless and harsh arid landscape. Remote cameras were deployed at bilby burrows to determine whether bilby burrows were important structures for other species. Cameras detected two mammal species, brush-tailed mulgara (Dasycercus blythi) and spinifex hopping mice (Notomys alexis), permanently occupying bilby burrows, and a further two species, short-beaked echidnas (Tachyglossus aculeatus acanthion) and sand goannas (Varanus gouldii), regularly using bilby burrows for shelter. An additional suite of 16 mammal, bird, reptile, amphibian and invertebrate species were detected interacting with bilby burrows. There was no difference in the number of species using disused or occupied bilby burrows, indicating that even disused bilby burrows are important structures for other species. We show that bilby burrows are used by a range of species and are analogous to the traditional, mostly North American, and commonly provided text book examples of the gopher tortoise and kangaroo rat. The disappearance of bilbies across at least 80% of their former range and thus the disappearance of their burrows as important structural resources in a harsh, arid environment may have had important consequences for a range of species. [ABSTRACT FROM AUTHOR]

Isolating DNA from scats (faeces) of threatened species is a valuable, non-invasive method for identifying individuals. To establish whether genotyping of greater bilby (Macrotis lagotis) individuals from faecal pellets collected in the field can be useful for population monitoring, an understanding of the DNA degradation rates is necessary. To determine the relationship between time and degradation of bilby faecal DNA, and assess whether a two-step elution process during extraction results in better-quality DNA, faecal pellets were collected from captive individuals, maintained under seminatural conditions, then harvested at known periods. DNA was amplified from faecal pellets with a 99% success rate and error rates of less than 5% up to 14 days after deposition. The amplification rate decreases, and the rate of allelic dropout increases with time, but DNA can still be amplified at rates above 60% and error rates below 15% at 90-180 days. We found that a second elution step was unnecessary, with more DNA amplified over a longer period using the first eluate. Viable DNA exists on bilby faecal pellets for a long period after deposition, which is useful for obtaining genetic samples for population monitoring programs and studies on population genetics. [ABSTRACT FROM AUTHOR]

Little is known of the area of occupancy, extent of occurrence, abundance, density or habitat use of the greater bilby (Macrotis lagotis) in the north of Western Australia. To seek broad collaborative agreement on a research agenda, the Western Australian Department of Parks and Wildlife hosted a workshop where research priorities were identified through a facilitated process. Five key areas for future research effort were identified: (1) refine survey methods, (2) improve understanding of habitat use, (3) improve understanding of the genetic structure of (meta)populations, (4) improve understanding of the threat posed by introduced predators and herbivores, and (5) improve understanding of how fire regimes affect bilby conservation. A conceptual model describing the main landscape components thought to be influencing distribution is used to reconcile existing knowledge, link research priorities for the bilby in the north of Western Australia, and guide the development of an integrated program of research. The broad nature of the priorities reflects the limited knowledge of bilbies in the north of the state; however, this research program provides an opportunity to increase knowledge to enact both species- and ecosystem-focused approaches to conservation, and potentially contributes towards the implementation of more dynamic conservation approaches for mobile species. [ABSTRACT FROM AUTHOR]

The article focuses on a study regrdaing contrasting effects of two mammalian soil engineers on microbial communities in Australia. It mentions that vertebrate species like greater bilby (Macrotis lagotis) and burrowing bettong (Bettongia penicillata) that dig in the soil by burrowing, foraging for insect larvae or excavating seed caches. It also mentions that soil-digging marsupial that has an extensive continental distribution because it is less susceptible to predation.

Hematologic and serum biochemistry blood reference intervals were established for the endangered marsupial, the bilby ( Macrotis lagotis). Blood samples were collected from 135 bilbies that were housed in a captive breeding colony or were free ranging in a 10-ha exclosure. Statistical analyses were undertaken, and significant differences in parameters were found depending on age, sex, and captive or free-ranging status of animals. These reference intervals will assist ongoing health and conservation management of this endangered marsupial species. [ABSTRACT FROM AUTHOR]

The endemic Australian greater bilby (Macrotis lagotis) is a vulnerable and iconic species. It has declined significantly due to habitat loss, as well as competition and predation from introduced species. Conservation measures include a National Recovery Plan that incorporates several captive breeding programs. Two of these programs were established within 12 months of one another (1997/98), with the same number and sex ratio of founding individuals, but executed different breeding strategies: (1) unmanipulated mating in semi-free range natural habitat versus (2) minimising mean kinship in large enclosures, with the supplementation of new individuals into both populations. This study evaluates the long-term genetic impact of these programs and examines the congruency between the pedigree studbook estimates of diversity and molecular data. Our data demonstrate that genetic diversity was maintained in both populations, with the supplementation of new individuals contributing to the gene pool. The studbook estimates of diversity and inbreeding are not consistent with the microsatellite data and should not solely be relied upon to evaluate the genetic health of captive populations. Our analyses suggest that captive breeding programs may not require costly and intensive management to effectively maintain long-term genetic diversity in a promiscuous species. [ABSTRACT FROM AUTHOR]

Bandicoots and bilbies (order Peramelemorphia) represent the principal group of omnivorous marsupials from a range of habitats across Australia and New Guinea. Bandicoots and bilbies most commonly use quadrupedal, asymmetrical half-bounding or bounding gaits and present an unusual combination of hind limb morphological features, including an ossified patella, a modified tibiofibular joint, and syndactylous morphology of the pes. We performed comparative dissections of the hind limb of the southern brown bandicoot (Isoodon obesulus fusciventer) (n = 13) and greater bilby (Macrotis lagotis) (n = 4), providing detailed descriptions of the muscular anatomy. These species displayed significant modification of the hind limb muscular anatomy and associated connective tissues, including emphasis on multiarticular muscles, such as the hamstrings, and extreme development of fascial structures. These patterns were more extreme in I. obesulus than in M. lagotis. Differences between the hind limb anatomy of I. obesulus and M. lagotis reflect the different ecological and environmental pressures on their locomotion and digging behaviours. Bandicoots and bilbies present an interesting assortment of skeletal attributes that set them apart from other marsupials. Here we provide a description of the hind limb muscles of the southern brown bandicoot (Isoodon obesulus) and greater bilby (Macrotis lagotis), and consider how morphology reflects behaviour among peramelemorphians. [ABSTRACT FROM AUTHOR]

Fences that exclude alien invasive species are used to reduce predation pressure on reintroduced threatened wildlife. Planning these continuously managed systems of reserves raises an important extension of the Single Large or Several Small (SLOSS) reserve planning framework: the added complexity of ongoing management. We investigate the long-term costefficiency of a single large or two small predator exclusion fences in the arid Australian context of reintroducing bilbies Macrotis lagotis, and we highlight the broader significance of our results with sensitivity analysis. A single fence more frequently results in a much larger net cost than two smaller fences. We find that the cost-efficiency of two fences is robust to strong demographic and environmental uncertainty, which can help managers to mitigate the risk of incurring high costs over the entire life of the project. [ABSTRACT FROM AUTHOR]

Rapid and reliable physiological evaluation of stress is necessary for understanding the potential impacts of environmental changes on managed populations of threatened mammals. In situ populations of Australia's iconic marsupial, the greater bilby ( Macrotis lagotis), are nearing extinction due to the impacts of competition and predation by feral animals and unpredictable climatic events (summer heat waves). In this study, we focussed our aim to identify a non-invasive method to measure adrenal activity in the species and also to identify potential factors that should be considered when comparing physiological stress in semi-free ranging populations of the species. We validated an enzyme immunoassay (EIA) for detecting fecal cortisol metabolites (FCM) from fresh fecal pellets taken from bilbies within four captive sites and two semi-free ranging populations around Queensland and New South Wales, Australia. Our FCM EIA successfully detected the 'raise and fall' pattern of FCM levels within 3 days of exogenous adrenocorticotropic hormone (ACTH) challenge. Mean FCM levels differed significantly between the captive sites and between sexes. All male bilbies grouped outdoor in captivity expressed the highest mean FCM level in comparison to all captive males that were housed individually or as groups indoors. Also, semi-free ranging bilbies expressed higher mean FCM levels than the captive bilbies. Overall, our study successfully validated a non-invasive tool for monitoring physiological stress in the greater bilby. In the future, it will be worthwhile to consider factors such as housing conditions, sex and location when comparing the adrenal sensitivity to environmental changes, to help evaluate the success of management interventions (such as predator free enclosures) and support the survival of the species. [ABSTRACT FROM AUTHOR]

Natural weathering conditions can influence faecal cortisol metabolite (FCM) measurements in wildlife if fresh faeces cannot be collected immediately following defaecation. In this study, we evaluated this issue in a threatened Australian marsupial, the greater bilby (Macrotis lagotis). Fresh (<12 h since defaecation) faecal samples (n = 19 pellets per bilby) were collected one morning from seven adult bilbies kept in captivity. One control faecal sample (Day 1) from each bilby was immediately frozen. The remaining faecal pellets were randomly positioned outdoors. Subsequently, we froze one faecal pellet every 24 h for 19 days. FCM levels in bilby faeces were quantified using an enzyme-immunoassay. Mean FCM levels showed variation (daily mean coefficients of variation [CV %]) of 56.83-171.65% over 19 days. Overall, FCM levels were affected by exposure time; however, multiple comparisons showed that no significant change in FCM occurred after environmental exposure (no significant difference in mean FCM between control (Day 1) with any of the exposure days (Days 2-19). Individuals and sex also affected FCM levels. We found no correlation between mean daily CVs with daily minimum-maximum temperatures or rainfall. Our results indicate that FCM in bilby faeces is fairly stable to long-term environmental exposure (19 days). In future, freshly excreted bilby faeces (where the sample maintains a distinct odour for 9-13 days) should be used to study FCM levels in wild bilbies. We determined the decay of faecal cortisol metabolite (FCM) in greater bilby (Macrotis lagotis) faeces during exposure to natural weathering. Our results recommend that freshly excreted bilby faeces (where the sample maintains a distinct odour for 9-13 days) should be used to study FCM levels in wild bilbies. [ABSTRACT FROM AUTHOR]

European settlement has had a dramatic impact on the distribution and abundance of peramelid (bandicoot and bilby) marsupials. Predation and competition from introduced species and altered habitat have been implicated in their decline or extinction. Bandicoots and bilbies inhabit a broad range of habitats in Australia. Research on the distribution, morphology, gastrointestinal histology, lactation, metabolism and nutritional physiology of extant peramelid species has increased in the last few decades. This paper provides a review that encompasses recent nutritional-based research. Peramelid research is mostly limited to only three species - Isoodon macrourus, Perameles nasuta and Macrotis lagotis - which prevents effective comparisons between species. Peramelids are broadly classified as omnivores and possess relatively uncomplicated gastrointestinal tracts. The caecum is the region of greatest diversity among species. The relatively large caecum of Chaeropus ecaudatus supports the theory that this species may have been the only herbivorous peramelid. The caecum of M. lagotis is less pronounced than other species and is continuous with the proximal colon. M. lagotis also has a longer total colon length, which aids water conservation to ensure survival in an arid environment. Temperate-zone species such as I. macrourus, I. obesulus and P. nasuta are more similar to each other with respect to gastrointestinal morphology than either C. ecaudatus or M. lagotis. Additional research on the morphometrics of the gastrointestinal tracts of P. gunnii, P. bougainville, P. eremiana, M. leucura and I. auratus would enable further comparisons to determine whether differences are a result of geographic distribution, habitat preference or variation between genera and/or individual species. [ABSTRACT FROM AUTHOR]

Many threatened species’ reintroductions in Australia fail because of predation by introduced cats and foxes. We attempted to improve reintroduction outcomes by training greater bilbies, Macrotis lagotis, to recognize cats as predators. The movement and behaviour of trained and control bilbies were compared in both a predator-free environment and in an area where cats and foxes were present. Trained bilbies within the predator-free environment moved significantly further, used more burrows with more entrances and changed burrows more frequently than untrained control animals. Trained bilbies also moved burrows when presented with olfactory predator stimuli while control bilbies did not. However, when bilbies were reintroduced to an area where predators were present, there was no difference in survival, movement or burrow use between trained and control bilbies. Both groups exhibited high survival rates in the first 6months after release. In the presence of predators, both trained and control bilbies appeared to be more predator-aware possibly because of control bilbies learning from trained conspecifics or cohabiting rabbits or through inadvertent contamination of control animals during training. Results suggest that bilbies can be taught to recognize exotic predators but this may not necessarily translate into improved reintroduction success in the wild. Further investigation into cultural and filial transfer of antipredator behaviour is recommended. [Copyright &y& Elsevier]

Abstract: Many animals create soil surface depressions (pits) while foraging for subterranean resources. Foraging pits typically fill with litter, organic debris and seed, retain moisture, and become hotspots for plant germination. This study aimed to examine whether artificial foraging pits, which mimic those created by Greater bilbies (Macrotis lagotis) and Burrowing bettongs (Bettongia lesueur), develop into patches of enhanced plant germination due to accumulation of leaf litter, or whether physical characteristics of the pits such as temperature and soil moisture influence germination, irrespective of the presence of litter. Compared with the soil surface, significantly more plants germinated in artificially-created foraging pits, irrespective of whether they received added litter. Daytime temperatures were 17–31% (7–11°C) cooler in foraging pits than on the adjacent soil surface, and pits retained significantly more moisture up to 5 days after rainfall. Our results suggest that the mesic conditions in foraging pits may be more important in promoting germination of vascular plants than the presence of litter. [Copyright &y& Elsevier]

The greater bilby (Macrotis lagotis) is the sole remaining species of desert bandicoot on the Australian mainland. The mating system of this species remains poorly understood, due to the bilby's cryptic nature. We investigated the genetic mating system of the greater bilby in a five-year study of a semi-free-ranging captive population that simulated their wild environment. Morphological traits were examined to determine whether these influenced patterns of male reproductive success and whether selection was acting on them. In any given year more than half the males (59.2±9.3%) failed to sire any offspring. Approximately 70% of sires fathered one offspring, and 30% two or three offspring. Since paternity was not dominated by few males, and given the species' solitary nature, lack of territoriality and large home ranges, it is likely that males adopt a roving strategy to find receptive females. These results are consistent with an overlap promiscuous mating system. Sires and non-sires could not be distinguished by their morphological traits, and there was no evidence for strong linear or non-linear selection on male traits. These data increase our understanding of bandicoot life-history traits and will assist conservation and management efforts. [ABSTRACT FROM AUTHOR]

The greater bilby Macrotis Iagotis once occupied about 70% of the Australian mainland but is now restricted in occurrence to just 20% of its former range. It is classified as Extinct in New South Wales. We assessed the major components of the diet of a recently re-introduced population of bilbies at Scotia Sanctuary, in western New South Wales, from faecal material collected over a period of 13 months. Animals consumed more invertebrates than green plant material and seeds throughout the study, although there was temporal variation in the presence of these food categories. Five orders of invertebrates were identified, with Coleoptera (beetles) occurring in more than 80% of faecal samples and Isoptera (termites) and Formicidae (ants) in 48% and 40%, respectively.These results identify key components of the diet of the first population of bilbies in New South Wales since the early 20th century and, combined with detailed studies of habitat requirements and prey abundance, should assist with selection of additional sites to expand the distribution of this iconic species further in future. [ABSTRACT FROM AUTHOR]

The greater bilby, Macrotis lagotis, is a species of conservation significance in the arid and semiarid zones of Australia. A species recovery program has been underway since the mid-1990s but the incorporation of molecular genetic data within the program has been difficult due to the problems of obtaining regular, population-wide samples of this trap-shy and sparsely distributed species. In this study, we demonstrate that faecal pellets collected from around burrows in the dry, arid habitat of western Queensland provide a viable source for DNA extraction and analysis. Faecal DNA was used to generate population-level estimates of microsatellite and mtDNA diversity for comparison with previous estimates for the natural population derived from tissue samples. Data were used to assess both the reliability of faecal-derived genotypes and the extent of any diversity loss since the previous study. Microsatellite diversity recorded from eight polymorphic markers for the natural population (A=4.31±0.30, HE=0.76±0.03) was comparable with the previous study, indicating little change in genetic diversity for the natural population in the 10-year interim. Faecal genotypes generated for the recently reintroduced population matched the known number of founders as well as a known genotype, providing support for the reliability of the faecal DNA approach. The captive and reintroduced populations had significantly lower diversity levels than the natural population (A=3.59±0.28, HE=0.68±0.03; A=3.57±0.20, HE=0.65±0.03 respectively). Mitochondrial control region analysis, incorporating nested clade phylogeographic analysis (NCPA), agrees with earlier findings that populations of bilbies across the arid zone in Australia have only recently become fragmented, but the case for Queensland bilbies being strongly differentiated from other regions is diminished. Implications from this study include the need to further supplement the captive and reintroduced populations with additional out-bred individuals and that faecal DNA can be used effectively for ongoing monitoring and management of this species. [ABSTRACT FROM AUTHOR]

Endocrinology of the oestrous cycle, pregnancy and early lactation was investigated in captive Western Australian greater bilbies (Macrotis lagotis). Initially, six females were monitored for changes in urogenital cytology, plasma progestogen, pericloacal and pouch morphology in the absence of a male. This was followed by the introduction of a male and a reproductive assessment through mating, gestation and early lactation. In the absence of a male, there was no cyclical pattern of urogenital cytology, pericloacal or pouch development, and progestogen concentrations remained basal. Within 5 days of the introduction of a male, all females had a karyopycnotic index of 100%. Spermatozoa were present in the urogenital smear within 3 days of male introduction in all five females that gave birth. Five to 9 days after the introduction of a male, there was an increase in plasma progestogen concentration that remained elevated for 14–19 days. Six of the seven females gave birth approximately 3 days after reaching peak plasma progestogen concentrations. Gestation length ranged between 14 and 17 days. Plasma progestogen concentrations of the postpartum and early lactation period were lower (P< 0.0001) than during gestation, but greater (P< 0.0001) than those recorded before the introduction of a male. One female that gave birth early in the study that was examined until weaning of the pouch young showed a cyclical pattern of plasma progestogen secretion that ended at weaning. This study provides evidence that the luteal phase in the greater bilby is induced by the presence of a male. Similar to female reproductive physiology in the Peramelidae, elevated progestogen concentration in the greater bilby was extended into lactation. [ABSTRACT FROM AUTHOR]

The article outlines study conducted by Joshua V. Ross on the significance of metapopulation persistence to a dynamic landscape in the U.S. Conservation biologists and ecologists are interested in finding an optimal way in managing and conserving such metapopulations. Researchers found that the optimal strategy for maximizing metapopulation viability with a given fixed budget and costs depend upon on all the parameter values and costs associated with the species under consideration. They found that the optimal strategy in addressing the problem was to protect patches when landscape dynamics dominate metapopulations thar are strongly influenced by the dynamics of the landscape they inhabit including the greater bilby.

Substantial range declines of the greater bilby (Macrotis lagotis) and the burrowing bettong (Bettongia lesueur) are thought to have had dramatic effects on ecosystem processes in the Australian arid zone because of their impacts on surface soils. The reintroduction of bilbies and bettongs into a reserve in central Australia provided an opportunity to compare their ecosystem impacts with those of two prevalent fossorial animals; the exotic European rabbit (Oryctolagus cuniculus) and the native sand goanna (Varanus gouldii). Bilbies and bettongs dug deeper and wider pits, excavating significantly more soil than rabbits or goannas. Pit coverage was four-times greater, and significantly more soil was excavated in the reserve where bilbies, bettongs and goannas were enclosed together compared with a site outside the reserve where rabbits and goannas co-occurred, or within the reserve where goannas occurred alone. Goannas dug fewer holes outside the reserve than in either of the reserve paddocks. Litter and viable seed were restricted almost exclusively to the pits, and soil from pits had higher levels of labile carbon than non-pit surface soils. Compared with surface soils, bilby, bettong and goanna pits contained relatively more labile carbon than rabbit pits. The significantly greater soil excavation by the bilbies and bettongs, and higher concentrations of carbon in their pits, relative to rabbit and goanna pits, demonstrate that these reintroduced fossorial mammals play important roles in the creation of fertile patches in arid landscapes. The results suggest that the extirpation of Australia’s mammal fauna has been accompanied by a loss of key ecosystem processes. [Copyright &y& Elsevier]