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A large component of the anthropogenic biodiversity crisis is the loss of animal species. In response, there has been significant investment in reintroductions of species to their historical ranges. Predation by native and exotic predators, however, remains a barrier to success. Over the past 200 years, Australia has seen the highest rate of mammal extinction on earth, with mammals within a critical weight range (CWR: 35 g–5.5 kg) most affected due to predation by exotic predators. Populations of some threatened species now exist only in Tasmania, offshore islands, or predator-proof sanctuaries. The next critical step is to return native populations outside of predator-free areas, ‘beyond-the-fence’, on the continental mainland. Given our current inability to completely remove exotic predators from mainland ecosystems, how can we achieve successful mammal reintroductions? A potential solution is to drive adaptation of reintroduced animals towards predator-resistance by exposing them to low levels of predation. We propose the concept of a ‘Goldilocks Zone’—the ‘just right’ levels of predation needed to drive selection for predator-resistant native species, while ensuring population viability. We experimentally reintroduced a mammal, the eastern bettong (Bettongia gaimardi), to mainland Australia, 100 years after its local extinction. Using an intense baiting regime, we reduced the population density of the red fox (Vulpes vulpes), the main factor behind the eastern bettong’s extirpation from the continent. Reducing bait take to 15% of previous levels allowed differential survival among bettongs; some surviving under 100 days and others over 450 (~ 4 times longer than some similar trials with related species). Surviving individuals were generally larger at release than those that died earlier, implying selection for larger bettongs. Our results suggest that reducing predation could establish a Goldilocks Zone that could drive selection for bettongs with predator-resistant traits. Our work contributes to a growing body of literature that explores a shift towards harnessing evolutionary principles to combat the challenges posed by animal management and conservation.

Invasive mammalian predators have had a devastating effect on native species globally. The European red fox (Vulpes vulpes) is one such species where it has been introduced in Australia. A novel but unexplored tactic to reduce the impact of mammalian predators is the use of unrewarded prey odors to undermine the effectiveness of olfactory hunting behavior. To test the viability of unrewarded prey odors in an applied setting we investigated how foxes responded to the odors of three different prey species. We used the odors of two locally extinct native Australian marsupials; the eastern quoll (a smaller carnivore) and eastern bettong (a fungivore), and the European rabbit, an introduced herbivore. Conducting our research over a period of 3 weeks in a pastoral environment in South‐eastern Australia, we used video observations of foxes' behaviors, as they encountered the different odors. We found a reduction in the number of fox visits to bettong odors in the third week. In contrast, we observed a sustained number of visits to rabbit odors. Foxes also spent more time investigating rabbit odors and displayed longer durations of vigilance behavior at quoll odors. Our results support the hypothesis that the exposure of wild foxes to unrewarded odors of novel prey species can reduce their interest in these odors, which might translate to a reduction in predation pressure. Our results also suggest, however, that olfactory pre‐exposure may not be as effective at reducing fox interest in a competitor species' odor.

Grasslands and grassy woodlands worldwide have experienced declines in extent and condition, with substantial changes to their ground-layer biodiversity. In Australia, this decline has coincided with the extinction of many digging mammals that may have once created regeneration niches for native ground layer plants. These digging mammals are widely recognised as ‘ecosystem engineers’, due to their influence on biopedturbation and resultant soil functions. Yet there is uncertainty as to the benefits of digging in restoring grassland diversity with current levels of modification and the presence of exotic plants. We investigated the effect of digging by the reintroduced eastern bettong (Bettongia gaimardi) on seedling germination in a temperate grassy woodland in south-eastern Australia. We marked fresh bettong foraging pits and undisturbed control plots in dense and open grassland. We added seeds of seven native forb species and monitored germination and establishment over 2 years. We found significantly more seedlings in bettong pits than controls, particularly in dense grassland. This effect persisted beyond 1 year, suggesting that pits may have increased seedling survival in dry conditions. Surprisingly, native species displayed a stronger positive response to pits than exotic species, particularly in a wet year. There was an initial reduction in exotic species, but this was followed by their increase in 1-year-old pits, suggesting that the disturbance created by digging could eventually lead to an increase in weed abundance. Our results demonstrate that while bettong pits provide a germination niche for native forbs, reintroducing digging animals will not necessarily result in the desired restoration outcomes. Ongoing persistence of exotic species is to be expected, and seed addition may be required for species that are seed-limited.

Studies of impacts of fragmentation have focused heavily on measures of species presence or absence in fragments, or species richness in relation to fragmentation, but have often not considered the effects of fragmentation on ranging behavior of individual species. Effective management will benefit from knowledge of the effects of fragmentation on space use by species.We investigated how a woodland specialist, the eastern bettong (Bettongia gaimardi), responded to fragmentation in an agricultural landscape, the Midlands region of Tasmania, Australia. We tested whether individual bettongs could adjust home range size to maintain access to essential habitat across three sites differing in degree of fragmentation.We used GPS tracking to measure the home ranges of individual bettongs. Our models tested the effects of habitat aggregation and habitat amount measured at two radii comparable to a typical core range (250 m) and a typical home range (750 m), and habitat quality and sex on individual home range. We also tested the relationship between fragmentation on woodland used to determine whether individuals could compensate for fragmentation.Depending on the spatial scale of fragmentation measured, bettongs altered their movement to meet their habitat requirements. Our top model suggested that at the core range scale, individuals had smaller ranges when habitat is more aggregated. The second model showed support for habitat amount at the core range, suggesting individuals can occupy larger areas when there is a higher amount of habitat, regardless of configuration.Species that are relatively mobile may be able to compensate for the effects of habitat fragmentation by altering their movement. We highlight that any patch size is of value within a home range and management efforts should focus on maintaining sufficient habitat especially at the core range scale., For a mobile species that can cross gaps, the configuration of patches does not hinder movement given there is sufficient habitat.

When does a reintroduced population of animals become self-regulating? Quantifying this is critical in determining when interventions can be tapered off, or when they may need to be reinstated. We tracked the growth trajectory of a reintroduced population to establish whether it was irruptive and/or had transitioned to self-regulation. In 2012, we reintroduced 32 eastern bettongs (Bettongia gaimardi), a potoroid marsupial from Tasmania, Australia, to a 485 ha exotic predator-proof fenced reserve in the Australian Capital Territory. We established a 92 cage trap monitoring network to track population growth between the Austral Autumn 2014 and Summer 2018. We used capture-recapture models to track changes in the population through time, and modelled ‘bettong weight’, ‘pouch occupancy’ and ‘age of pouch young’ with population variation, to establish potential associations with changes in population size. The estimated population grew from 32 individuals in 2012 to 100 in 2014, 192 in Autumn 2016, and then declined to 151 in Summer 2018. Estimated survival of adults was high—above 92% between most sessions. Adult female weights ranged between 0.485 and 2.428 kg, and adult males between 0.470 and 2.775 kg. Our study showed density dependence was achieved over the 6 year period. Low adult mortality, and variable pouch occupancy related to female weight, suggested that food availability had influenced lactation in females, with flow-on impacts on juvenile survival. Long-term, broad-scale population dynamics were probably driven by a mix of direct (e.g. disease, harvesting for other reintroductions), and indirect (i.e. climate dependent availability of nutritious food) influences on population size.

Faecal samples (n = 1,093) collected from the woylie Bettongia penicillata Gray, in south-western Australia were examined for the presence of coccidian parasites. Eimeria sp. oocysts were detected in 15.2% of samples. Faecal samples obtained from the eastern bettong Bettongia gaimardi (Desmarest) (n = 4) and long-nosed potoroo Potorous tridactylus (Kerr) (n = 12) in Tasmania, were also screened for the presence of Eimeria spp. (prevalence 50% and 41.7%, respectively). Morphological and genetic comparison with other known species of Eimeria indicates that the material identified in woylies is novel. This study aimed to (i) morphologically describe and genetically characterise Eimeria woyliei n. sp. found in woylies; and (ii) genetically characterise Eimeria gaimardi Barker, O’Callaghan & Beveridge, 1988, Eimeria potoroi Barker, O’Callaghan & Beveridge, 1988, and Eimeria mundayi Barker, O’Callaghan & Beveridge, 1988, from other potoroid marsupials. Molecular phylogenetic analyses conducted at the 18S rDNA and mitochondrial cytochrome c oxidase subunit 1 (cox1) loci revealed that E. woyliei n. sp. was most closely related to Eimeria setonicis Barker, O’Callaghan & Beveridge, 1988, at the 18S rDNA locus, and Eimeria trichosuri O’Callaghan & O’Donoghue, 2001, at the cox1 locus. Eimeria woyliei n. sp. is the sixth species of Eimeria to be formally described from potoroid marsupials.

The decline of ecosystem engineers alters ecosystems, with impacts cascading through to other organisms. Through engineering and predation, digging mammals may affect burrowing invertebrate assemblages, leading to changes in invertebrate-driven soil engineering. Using a mammal reintroduction sanctuary in southern Australia, we tested how digging mammals alter invertebrate burrows (density and size of burrow entrances) and whether these impacts were scale-dependent. We examined the micro-site (pit-scale) effects of mammal foraging pits on invertebrate burrowing activity by comparing natural and artificial pits and bare-ground, and artificial pits of different dimensions within different microhabitat types. To test how mammals affected invertebrate burrows and soil physical and chemical properties at larger scales, we used an exclusion experiment (plot-scale) and surveys inside and outside a reintroduction reserve (landscape scale). Invertebrate burrows were more numerous in mammal pits than bare-ground and artificial pits, and larger in mammal pits than bare-ground. The density and size of invertebrate burrows depended on pit morphology, with burrow density greatest in narrow bilby pits and large burrows favoured by bettong pits. However, the influence of foraging pits on invertebrate burrows was scale-dependent: changes in invertebrate burrows were not detected at the plot or landscape scale. Only 4.5% of land surface area was occupied by pits and this might be insufficient to alter burrow or soil properties detectably in un-stratified surveys at larger scales. Digging mammals altered the small-scale (but not large-scale) distribution of invertebrate burrows, suggesting that their reintroduction provides an avenue through which to restore the heterogeneity of other organisms and functions in ecosystems.

Understanding the conditions under which small native Australian mammals can persist in the presence of introduced predators remains a key challenge to conservation ecologists. Bettong‐specific one‐way gates were used at a predator‐free reserve in South Australia to allow the burrowing bettong (Bettongia lesueur) – a small potoroid, listed as ‘vulnerable’ nationally – to disperse out of the reserve. We conducted a field experiment to explore the conditions affecting residence time of bettongs that left the reserve. We monitored bettong and mammalian predator activity outside the fence using track surveys across 18 sites over two seasons. We examined the effect of supplementary feeding as a strategy for increasing residence time, as well as the influence of predator presence and habitat quality, using linear mixed models. Bettong activity was positively associated with supplementary feeding, midstorey vegetation cover and shelter availability. After gates were closed, bettong activity near gates declined to almost zero the following weeks, likely either due to death from predation or due to movement away from the sites. To a small extent, mammalian predators were more likely to be present at sites with high bettong activity. Further research on conditions to support persistence of burrowing bettongs and other small mammals, including understanding minimum necessary predator control effort, is required before successful establishment of populations outside of fences can occur.

The classical theory of island biogeography explains loss of species in fragmented landscapes as an effect of remnant patch size and isolation. Recently this has been challenged by the habitat amount and habitat continuum hypotheses, according to which persistence in modified landscapes is related to total habitat amount rather than habitat configuration or the ability of species to use all habitats to varying degrees. Distinguishing between these theories is essential for effective conservation planning in modified landscapes. Identify which factors of habitat type, amount and configuration predict the persistence of a keystone woodland specialist, the eastern bettong Bettongia gaimardi, in a fragmented landscape. In the Midlands region of Tasmania we carried out camera surveys at 62 sites in summer and winter. We included habitat and landscape features to model whether habitat amount or patch size and isolation influenced the presence of the eastern bettong, and to measure effects of habitat quality. Habitat amount within a 1 km buffer was a better predictor of occupancy than patch size and isolation. Occupancy was also affected by habitat quality, indicated by density of regenerating stems. Our results support the habitat amount hypothesis as a better predictor of presence. For a species that is able to cross the matrix between remnant patches and utilise multiple patches, the island biogeography concept does not explain habitat use in fragmented landscapes. Our results emphasize the value of small remnant patches for conservation of the eastern bettong, provided those patches are in good condition.

The conservation benefits of maintaining social groupings during and after animal translocations are unclear. Although some studies report improved post-release survival, others found no discernible influence on reintroduction success. Understanding the effects of social groupings is difficult because release methods can influence the animals’ ability to maintain social groups. We explored this relationship by first studying whether release protocols influenced post-release cohesion in the communal burrowing bettong Bettongia lesueur, and then investigating whether maintenance of social cohesion conferred any post-release advantage. We released bettongs into a small (8 ha) and large (2,600 ha) area and compared the proportion that maintained social groupings in the different settings. The proportion of bettongs sharing with previous warren co-occupants was higher than expected by chance in both areas, however, a significantly higher proportion of bettongs maintained social groupings in the small (75%) compared to the large release area (13%). This suggests bettongs prefer to maintain social groupings but are unable to locate members of their group in large release areas. Bettongs that did maintain social groupings showed no difference in reproductive or health outcomes compared to those that formed new social groupings, suggesting no benefit to reintroduction success. We conclude that release protocols can influence post-release cohesion, but that greater cohesion does not necessarily confer advantages to group-living animals. To test the importance of social cohesion, further research on reintroductions should compare post-release parameters for animals released using protocols that do and do not facilitate maintenance of social groupings.

Understanding the impacts of parasites on wildlife is growing in importance as diseases pose a threat to wildlife populations. Woylie (syn. brush-tailed bettong, Bettongia penicillata) populations have undergone enigmatic declines in south-western Western Australia over the past decade. Trypanosomes have been suggested as a possible factor contributing towards these declines because of their high prevalence in the declining population. We asked whether temporal patterns of infection with Trypanosoma spp. were associated with the decline patterns of the host, or if other factors (host sex, body condition, co-infection or rainfall) were more influential in predicting infection patterns. Species-specific nested PCRs were used to detect the two most common trypanosomes (T. copemani and T. vegrandis) from 444 woylie blood samples collected between 2006 and 2012. Time relative to the decline (year) and an interaction with co-infection by the other trypanosome best explained patterns of infection for both trypanosomes. The prevalence of single species infections for both T. copemani and T. vegrandis was lower after the population crash, however, the occurrence of co-infections increased after the crash compared to before the crash. Our results suggest an interaction between the two parasites with the decline of their host, leading to a higher level of co-infection after the decline. We discuss the possible mechanisms that may have led to a higher level of co-infection after the population crash, and highlight the importance of considering co-infection when investigating the role of parasites in species declines., Graphical abstract Image 1, Highlights • Woylie (bettong) populations have declined by >90% over 10 years. • Prevalence of Trypanosoma copemani and T. vegrandis increased during the decline, and reset to a lower level after the crash. • Overall prevalence of both Trypanosoma spp. decreased during the decline. • The proportion of hosts co-infected with both species of Trypanosoma spp. increased after the population crash. • Highlights the need to consider co-infection and the effects of declining host populations on parasite prevalence.

The failure of broadscale management to protect some threatened species has led to an increase in the use of islands and fenced reserves as translocation sites or foci for intensive threat mitigation. Although highly successful at excluding some threats, these sites may be prone to ecosystem imbalance due to the absence or removal of predators and competitors. We documented population trends and environmental impacts of the burrowing bettong, (Bettongia lesueur), a threatened herbivorous macropod reintroduced to a 1400 ha fenced reserve in arid Australia for 17 years after release. The population increased from 30 individuals to an estimated 1532 individuals (1.09 per ha), a density up to ten times higher than wild populations. There was little evidence that population growth was density dependent, the average intrinsic rate of increase (r) was 0.125 and population size was unrelated to rainfall, body condition or reproductive output. Browse damage on palatable plant species increased, and cover of palatable shrub species decreased, with increased abundance of bettongs. Activity of another reintroduced herbivore, the greater stick-nest rat, (Leporillus conditor), declined as bettong abundance increased while a reintroduced species not reliant on herbage was unaffected. The burrowing bettong has been successfully reintroduced to the Arid Recovery fenced reserve but the positive average intrinsic rate of increase, inflated population density and impacts to resident plant and animal species suggests the population is now overabundant. This is the first documented case of overpopulation of a reintroduced species at a restricted site in Australia, highlighting the importance of preparing overpopulation management plans and considering reintroductions of species from all trophic levels including native predators.

Reintroduction programs aim to restore self-sustaining populations of threatened species to their historic range. However, demographic restoration may not reflect genetic restoration, which is necessary for the long-term persistence of populations. Four threatened Australian mammals, the greater stick-nest rat (Leporillus conditor), greater bilby (Macrotis lagotis), burrowing bettong (Bettongia lesueur) and western barred bandicoot (Perameles bougainville), were reintroduced at Arid Recovery Reserve in northern South Australia over the last 18 years. These reintroductions have been deemed successful based on population growth and persistence, however the genetic consequences of the reintroductions are not known. We generated large single nucleotide polymorphism (SNP) datasets for each species currently at Arid Recovery and compared them to samples collected from founders. We found that average genetic diversity in all populations at the Arid Recovery Reserve are close to, or exceeding, the levels measured in the founders. Increased genetic diversity in two species was achieved by admixing slightly diverged and inbred source populations. Our results suggest that genetic diversity in translocated populations can be improved or maintained over relatively long time frames, even in small conservation reserves, and highlight the power of admixture as a tool for conservation management.

Ecosystem engineers play an important role in resource availability and can be negatively impacted by anthropogenic disturbances, such as livestock grazing. The decline of digging and burrowing mammals in Australia is partly attributed to agriculture, however little is known about their use of microhabitats, and thus, how they respond to different cattle grazing regimes. Here, we examine the response of a marsupial ecosystem engineer, the rufous bettong (Aepyprymnus rufescens) to cattle grazing strategies and vegetation types, and examine whether microhabitat selection is driving this response. We hypothesized that rufous bettongs would be negatively impacted by heavy cattle grazing due to their use of ground-level microhabitat features. We conducted a mark-recapture trapping survey among four grazing treatments and in two vegetation types (box and ironbark woodlands), at a 20-year grazing trial in northern Australia. We modelled rufous bettong abundance in response to grazing treatment and vegetation type and determined microhabitat preference using Manly selection ratios. We found that rufous bettongs preferred ironbark and avoided heavy grazing. Thus, they avoided the areas of highest cattle utilization. On average, individuals preferred high grass and other terrestrial microhabitat variables of moderate complexity. Our results indicate that habitat selection is contributing to the response of a marsupial ecosystem engineer to different grazing strategies. Mammalian digging and burrowing ecosystem engineers should be a conservation focus on rangelands due to their positive influence on a suite of species, and their ability to potentially mitigate some of the negative impacts of cattle grazing on soil health.

Prey naivete is thought to be a significant factor contributing to the failure of native prey to re-establish in the presence of introduced predators. We tested whether exposing naive prey to low levels of in situ predation pressure from introduced predators could cause accelerated selection for certain physical or behaviour traits. Such selection could improve the chance of future co-existence between introduced predators and native prey. In 2014, we reintroduced 352 burrowing bettongs (Bettongia lesueur) into a 26 km2 fenced paddock where predation levels could be carefully controlled. Four feral cats (Felis catus) were introduced to the paddock several months after bettong reintroduction and predation events were subsequently recorded. We measured a suite of physical and behavioural traits on the bettongs prior to release and compared these between individuals that survived or were assumed to have died. Population level parameters were also compared between the reintroduced population and the predator-free source population. No a priori measured physical or behavioural traits were significant predictors of individual survival after release and the high survival rate of radio-collared bettongs and the positive population growth rate suggests that the predation pressure from the introduced feral cats may not have been sufficiently high to cause strong selection over a short time period. However, population level comparisons found cat-exposed male bettongs had significantly longer hind feet than the source population at 18–22 months after release. Hind foot length was consistently longer in both older released animals and younger recruits and thus may be an indicator of selection and/or phenotypic change in response to the presence of predators. Our study suggests that predation may cause phenotypic change over short time periods but that higher cat predation pressure may be required to enable the benefits of accelerated natural selection to be adequately assessed.

Large-scale plantations established for timber production can dramatically transform landscapes, however little is known about the response of more cryptic components of biodiversity. We report on trends in mammals and nocturnal birds during a 17 year longitudinal study on three large-scale plantations of locally indigenous eucalypts in northern New South Wales, Australia. The study began in a farmland mosaic and has continued to track occupancy after the establishment of eucalypt plantations within the paddock areas. Surveys were undertaken at focal trees located in different classes of remnant vegetation that became embedded within the plantations as well as in the plantation matrix itself. Reference sites were also sampled in adjacent blocks of forest. We recorded nine species of arboreal mammals and eight species of nocturnal birds during focal tree watches, while camera and Elliott traps recorded 19 ground-dwelling taxa. Eleven of these species are listed as threatened. The majority of species were present, but uncommon, at the start of our study in the cleared farmland-remnant vegetation mosaic. Multi-season, multi-scale occupancy analyses revealed most species were stable over time and, among mammals, a large temporal increase was most notable for common brushtail possum Trichosurus vulpecula. A potential decline was only observed for eastern chestnut mouse Pseudomys gracilicaudatus, a trend also evident in other small mammals. Among nocturnal birds, both southern boobook Ninox boobook and Australian owlet nightjar Aegotheles cristatus increased in occupancy over time. Increasers tended to be widespread species with generalist attributes, while stable or decreasing species were more likely to be specialists. Few arboreal mammals or nocturnal birds were recorded in the plantation matrix itself, though some ground mammals (e.g., rufous bettong Aepyprymnus rufescens) had higher occupancy rates in plantation. Rather, most species were associated with remnant vegetation and old growth elements within plantations and these likely function as a refuge for fauna (potentially during plantation harvest), provide specialised resources such as tree hollows and facilitate the colonisation of plantations. While few negative effects due to change in land-use to plantation were recorded, limited increase in occupancy for most species contrasts with overall positive trends reported previously for diurnal bird species. Low structural complexity and tree species diversity within plantations are likely to limit the number of winners. In the context of a timber plantation, additional management to enhance recovery would best be directed to areas excluded from future harvesting, such as environmental plantings in degraded riparian zones and limiting livestock grazing. The ecosystem implications of increasing populations of generalists such as T. vulpecula remain unclear.

Secondary seed dispersal by ants (myrmecochory) is an important process in semi-arid environments where seeds are transported from the soil surface to an ant nest. Microsites from which ants often remove seeds are the small pits and depressions made by native and exotic animals that forage in the soil. Previous studies have demonstrated greater seed retention in the pits of native than exotic animals, but little is known about how biotic factors such as secondary seed dispersal by ants affect seed removal and therefore retention in these foraging pits. We used an experimental approach to examine how the morphology of burrowing bettong (Bettongia lesueur), greater bilby (Macrotis lagotis), short-beaked echidna (Tachyglossus aculeatus) and European rabbit (Oryctolagus cuniculus) foraging pits and ant body size influenced ant locomotion and seed removal from pits along an aridity gradient. Ants took 3.7-times longer to emerge from echidna pits (19.6 s) and six-times longer to emerge from bettong pits (30.5 s) than from rabbit pits (5.2 s), resulting in lower seed removal from bettong pits than other pit types. Fewer seeds were removed from pits when cages were used to exclude large body-sized (>2 mm) ants. Few seeds were removed from the pits or surface up to aridity values of 0.5 (humid and dry sub-humid), but removal increased rapidly in semi-arid and arid zones. Our study demonstrates that mammal foraging pit morphology significantly affects ant locomotion, the ability of ants to retrieve seeds, and therefore the likelihood that seeds will be retained within foraging pits.

Faecal glucocorticoid metabolites are minimally invasive stress physiology indices that can be used to understand how animals respond to physical and/or psychological challenges (stressors) and inform how to optimize conservation management in view of these stressors. We investigated contextual biological, environmental and parasitological factors influencing variation in baseline faecal cortisol metabolite (FCM) concentration in a critically endangered marsupial, the woylie (syn. brush-tailed bettong, Bettongia penicillata). Woylies have undergone a rapid and significant population decline, with environmental stressors exacerbating disease suggested to contribute to these ongoing declines. We conducted a longitudinal field study of 15 adult woylies (9 females, 6 males) in a captive, naturalistic facility. FCM concentration in faecal samples (n = 269) collected monthly over 20 months was quantified by enzyme immunoassay in parallel with measures of body condition, sex, season, female reproductive status and the presence of endoparasites and ectoparasites. Linear mixed effect modelling revealed a significant effect of season, sex, body condition index and nematode parasite status on FCM. Overall, mean FCM was lowest in summer and highest in autumn and winter, and females had higher mean FCM than males. There was a significant but weak negative association between body condition and FCM. When woylies were shedding oxyurid nematode eggs they had higher mean FCM compared to when they were not shedding. In future, knowledge of factors that influence FCM fluctuations in woylies may be considered when carrying out potentially stressful conservation interventions that may influence the future survival of this unique and threatened species.

Temperate grasslands and woodlands are the focus of extensive restoration efforts worldwide. Reintroduction of locally extinct soil-foraging and burrowing animals has been suggested as a means to restore soil function in these ecosystems. Yet little is known about the physical and chemical effects of digging on soil over time and how these effects differ between species of digging animal, vegetation types or ecosystems. We compared foraging pits of a native reintroduced marsupial, the eastern bettong (Bettongia gaimardi) and that of the exotic European rabbit (Oryctolagus cuniculus). We simulated pits of these animals and measured pit dimensions and soil chemical properties over a period of 2 years. We showed that bettong and rabbit pits differed in their morphology and longevity, and that pits had a strong moderating effect on soil surface temperatures. Over 75% of the simulated pits were still visible after 2 years, and bettong pits infilled faster than rabbit pits. Bettong pits reduced diurnal temperature range by up to 25 °C compared to the soil surface. We did not find any effects of digging on soil chemistry that were consistent across vegetation types, between bettong and rabbit pits, and with time since digging, which is contrary to studies conducted in arid biomes. Our findings show that animal foraging pits in temperate ecosystems cause physical alteration of the soil surface and microclimatic conditions rather than nutrient changes often observed in arid areas.

Spillover effects are an expansion of conservation benefits beyond protected areas through dispersal of species that reside within. They have been well documented in marine but not terrestrial systems. To understand the effects on wildlife created by conservation fences, we explored the internal and external gradients of activity in mammal, reptile, and bird species at a conservation reserve in arid Australia that is fenced to exclude invasive rabbits (Oryctolagus cuniculus), cats (Felis catus), and foxes (Vulpes vulpes). Two methods were used: counts of animal tracks along transects on sand dunes and captures at pitfall-trapping sites. In both cases, sites were spaced at different distances from the reserve fenceline inside and outside the reserve. We recorded a range of spillover, source-sink, step, and barrier effects that combined to create a zone within and around the reserve with fence-induced species-specific wildlife gradients. Two endemic rodents but none of the 4 mammal species reintroduced to the reserve showed positive spillover effects. Barrier effects, where activity was highest close to the fence, were recorded for the feral cat and native bettong (Bettongia lesueur), species that could not breach the fence. In comparison, some reptiles and native mammal species that could permeate the fence displayed source-sink effects; that is, their activity levels were reduced close to the fence likely due to constant emigration to the side with lower density. Activity of some reptiles was lowest at sites inside the reserve and gradually increased at outside sites with distance from the fence, a gradient likely related to trophic cascades triggered by predator exclusion. Our result shows that fenced reserves can create overlapping layers of species-specific gradients related to each species' ability to permeate the fence and its varying susceptibility to threats. Managers should be aware that these gradients may extend for several kilometers either side of the fence and that not all contained species will increase in abundance. Creating wider conservation benefits may require increased fence permeability and threat reduction outside the fence.Exploración de los gradientes de vida silvestre internos y externos creados por las vallas de conservación. Resumen Los efectos de derrame son una expansión de los beneficios de conservación más allá de las áreas protegidas a través de la dispersión de especies que residen en su interior. Han sido bien documentados en sistemas marinos, pero no terrestres. Para entender los efectos de las vallas de exclusión sobre la vida silvestre, exploramos los gradientes internos y externos de la actividad de especies de mamíferos, reptiles y aves en una reserva de conservación en la región árida de Australia que está cercada para excluir conejos invasivos (Oryctolagus cuniculus), gatos (Felis catus) y zorros (Vulpes vulpes). Se utilizaron dos métodos: conteo de huellas de animales a lo largo de transectos en dunas de arena y captura con trampas pitfall. En ambos casos, los sitios fueron espaciados a distintas distancias dentro y fuera de la valla de la reserva. Registramos una gama de efectos de derrame, fuente-sumidero, escalón y barrera que se combinaron para crear una zona dentro y alrededor de la reserva con gradientes de vida silvestre inducidos por la valla. Dos roedores endémicos, pero ninguna de 4 especies de mamíferos reintroducidas a la reserva, mostraron efectos de derrame positivos. Los efectos de barrera, donde la actividad era mayor cerca de la valla, fueron registrados para el gato feral y la rata canguro nativa (Bettongia lesueur), especies que no pudieron franquear la valla. En contraste, algunas especies de reptiles y mamíferos nativos que pudieron permear la valla mostraron efectos de fuente-sumidero; esto es, sus niveles de actividad fueron bajos cerca de la valla probablemente debido a la emigración constante hacia el lado con menor densidad. La actividad de algunos reptiles fue menor en los sitios núcleo de la reserva e incrementaron a medida que incrementó la distancia hacia afuera, un gradiente relacionado probablemente con las cascadas tróficas desencadenadas por la exclusión de depredadores. Nuestros resultados muestran que las reservas cercadas pueden crear capas sobrepuestas de gradientes específicos relacionados con la habilidad de cada especie para permear la valla y su susceptibilidad a las amenazas. Los manejadores deber ser conscientes de que esos gradientes pueden extenderse varios kilómetros a ambos lados de la valla y que no todas las especies contenidas aumentarán en abundancia. La creación de beneficios de conservación más amplios puede requerir una mayor permeabilidad de la vallas y la reducción de amenazas fuera de la reserva.溢出效应是指生活在保护区的物种扩散到保护区之外带来额外保护效益的现象, 目前在海洋保护区已有很多相关报道, 但在陆地生态系统中尚且没有。为了解保护围栏对野生动物的影响, 我们在澳大利亚干旱地区的一个保护区中探究了围栏内外哺乳动物、爬行动物和鸟类的活动梯度变化, 这个保护区建造围栏是为了阻挡入侵物种穴兔 (Oryctolagus cuniculus) 、家猫 (Felis catus) 和狐狸 (Vulpes vulpes) 。我们采用了两种调查方法: 沿沙丘样带的动物足迹数量, 以及陷阱诱捕位点的捕获情况;两种方法都分别调查了从保护区围栏向内和向外不同距离的位点。我们发现一系列的溢出效应、源汇效应、阶梯效应和屏障效应, 它们共同导致了保护区内部及周围由围栏引起的物种特异的野生动物梯度带。四种重引入到保护区的哺乳动物没有正溢出效应, 但在两种特有啮齿类动物中存在这种效应。在流浪猫和当地的草原袋鼠 (Bettongia lesueur) 这两种不能翻越围栏的动物中出现了屏障效应, 即围栏附近动物活动最频繁的现象。相比之下, 一些可以穿过围栏的爬行动物和原生哺乳动物则表现出源汇效应, 即在围栏附近的活动水平降低, 这可能是因为它们会不断向密度较低的一侧迁移。另外, 一些爬行动物在保护区核心位点的活动强度最低, 而距离核心位点越远活动强度越大, 这样的梯度可能与捕食者排斥引发的营养级联有关。我们的结果表明, 有围栏的保护区可以创造出与物种穿越围栏的能力和对威胁的敏感度有关的物种特异性梯度, 并形成相互重叠的分布层。管理者应意识到这些梯度可能会延伸至围栏两侧数公里处, 此外, 并不是所有被围住的物种丰度都会增加。为了创造更广泛的保护效益, 可能需要提高围栏的可穿越性并减少围栏外的威胁。【翻译: 胡怡思; 审校: 聂永刚】.

The three surviving ‘brush-tailed’ bettong species—Bettongia gaimardi (Tasmania), B. tropica (Queensland) and B. penicillata (Western Australia), are all classified as threatened or endangered. These macropodids are prolific diggers and are recognised as important ‘ecosystem engineers’ that improve soil quality and increase seed germination success. However, a combination of introduced predators, habitat loss and disease has seen populations become increasingly fragmented and census numbers decline. Robust phylogenies are vital to conservation management, but the extent of extirpation and fragmentation in brush-tailed bettongs is such that a phylogeny based upon modern samples alone may provide a misleading picture of former connectivity, genetic diversity and species boundaries. Using ancient DNA isolated from fossil bones and museum skins, we genotyped two mitochondrial DNA (mtDNA) genes: cytochrome b (266 bp) and control region (356 bp). These ancient DNA data were combined with a pre-existing modern DNA data set on the historically broadly distributed brush-tailed bettongs (~300 samples total), to investigate their phylogenetic relationships. Molecular dating estimates the most recent common ancestor of these bettongs occurred c. 2.5 Ma (million years ago), which suggests that increasing aridity likely shaped their modern-day distribution. Analyses of the concatenated mtDNA sequences of all brush-tailed bettongs generated five distinct and well-supported clades including: a highly divergent Nullarbor form (Clade I), B. tropica (Clade II), B. penicillata (Clades III and V), and B. gaimardi (Clade IV). The generated phylogeny does not reflect current taxonomy and the question remains outstanding of whether the brush-tailed bettongs consisted of several species, or a single widespread species. The use of nuclear DNA markers (single nucleotide polymorphisms and/or short tandem repeats) will be needed to better inform decisions about historical connectivity and the appropriateness of ongoing conservation measures such as translocations and captive breeding.

Prey may have ontogenetic experience, evolutionary experience, or both types of experiences with their predators and how such experiences influences their ability to identify their predators is of great theoretical and applied interest. We capitalized on predator-free exclosures containing populations of native burrowing bettongs (Bettongia lesueur) and introduced rabbits (Oryctolagus cuniculus) that ensured we had knowledge of our subjects’ ontogenetic experiences with predators and asked whether evolutionary experience influenced their visual predator discrimination abilities. Rabbits evolved with red foxes (Vulpes vulpes) and wolves (Canis lupus) but had less than 200 years of prior exposure to dingoes. The rabbit population we studied had been exposed to dingoes (Canis dingo) and foxes 8 months prior to our study and had heightened responses to red fox models, but not dingo/dog (Canis dingo/Canis familiaris) models. The insular burrowing bettong population had no ontogenetic exposure to mammalian predators, brief evolutionary exposure to domestic dogs and possibly dingoes, and a deeper evolutionary history of exposure to thylacines (Thylacinus cynocephalus)—another large mammalian predator with convergent body morphology to dingoes/dogs but no evolutionary or ontogenetic exposure to foxes. Bettongs showed a modest response to the dingo/dog model and no response to the fox model. These results are consistent with the hypothesis that deep evolutionary history plays an essential role in predator discrimination and provides support for the multipredator hypothesis that predicts the presence of any predators can maintain antipredator behavior for other absent predators. Prey may have ontogenetic experience and or evolutionary experience with their predators. How such experiences influence prey species’ ability to identify their predators is of significance to theory on the evolution of antipredator response and to improve the success of translocations and reintroductions for conservation purposes which often fail because of predation on predator naive prey. Here, we show that prey recognition for two prey species with limited or no ontogenetic exposure to predators, rabbits, and burrowing bettongs was greatest toward the predator to which they had the longest period of coevolution. The results are consistent with the hypothesis that evolutionary history plays an essential role in predator discrimination and provides support for the multipredator hypothesis that predicts the presence of any predators can maintain antipredator behavior for other absent predators.

The eastern bettong Bettongia gaimardi, a potoroid marsupial, has been extinct on the Australian mainland since the 1920s. Sixty adult bettongs were reintroduced from the island of Tasmania to two predator-free fenced reserves on mainland Australia. We examined baseline health parameters (body weight, haematology and biochemistry, parasites and infectious disease exposure) in a subset of 30 (13 male, 17 female) individuals at translocation and again at 12–24 months post-reintroduction. The mean body weight increased significantly post-reintroduction but there were no significant differences in body weight between the two reintroduction sites or between the sexes in response to reintroduction. Differences were evident in multiple haematological and biochemical variables post-reintroduction but there were few differences between the two reintroduced populations or between the sexes in response to reintroduction. Ectoparasite assemblages differed, with five of 13 species failing to persist, and an additional four species were identified post-reintroduction. None of the bettongs had detectable antibodies to the alphaherpesviruses Macropodid herpesvirus 1 and 2 post-reintroduction, including one individual that was seropositive at translocation. Similarly, the novel gammaherpesvirus potoroid herpesvirus 1 was not detected by polymerase chain reaction (PCR) in any of the bettongs post-reintroduction, including one individual that was PCR-positive at translocation. None of the bettongs had detectable antibodies to Toxoplasma gondii either at translocation or post-reintroduction. Our data demonstrate changing baseline health parameters in eastern bettongs following reintroduction to the Australian mainland are suggestive of improved health in the reintroduced populations, and provide additional metrics for assessing the response of macropodoids to reintroduction.

Mycophagous bioturbators provide ecosystem services that can be important for the resilience and restoration of ecosystems. Among the Australian mammals, mycophagy is most prevalent within the Potoroidae (bettongs and potoroos). However, proportionally more species of Potoroidae are either recently extinct or currently threatened than any other mammalian family in Australia, and they are among the least studied. The critically endangered woylie, or brush-tailed bettong (Bettongia penicillata), is a mycophagous, ground dwelling 'ecosystem engineer' that was one of Australia's most abundant and widely distributed potoroids prior to European settlement. After substantial range contraction, however, the remaining indigenous populations are now restricted to eucalypt forests in south-western Australia. Using an experimental approach, we investigated the population responses of the woylie to timber harvesting in these forests. Nine treatments, including varying logging intensities and unharvested controls, were applied at 22 sites. The abundance of the woylie in the harvested areas, in unharvested stands between logged areas, and in extensive unharvested stands outside the harvest management area were compared using a replicated before-after-control-impact (BACI) repeated measures design and capture-mark-recapture modelling. A total of 5860 captures of 815 individuals were recorded during 35 trapping sessions over 16 years (one year preceding, two years during, and 13 years after disturbance). Capture rate was a good index of abundance for this species and woylie abundance, survivorship and recruitment were not adversely affected by silvicultural practices in the jarrah (Eucalyptus marginata) forest. On the contrary, the harvested areas may have afforded some localised protection when an unrelated, species-wide decline began three years after harvesting disturbance ended; woylie numbers declined by up to 77% and 95% in harvested and unharvested areas, respectively. Thus the nature and spatial extent of the timber harvesting regimes investigated in this study were not a major threatening process for this species. However, ongoing monitoring and evaluation are necessary to ensure that timber harvesting activities remain benign in the face of a changing climate, possible increased mortality from introduced predators, disease, and further declines in the abundance of this critically endangered marsupial.

Captive breeding plays an increasingly significant role in conservation programs, providing program managers with the challenge of preventing over-crowding, whilst also maintaining genetic and behavioural integrity of the population. This thesis assesses a new approach to the reproductive and genetic management of individuals in conservation programs by using contraception. Suprelorin contraceptive implants containing the GnRH agonist deslorelin were used to manage reproduction in two conservation-dependent species, the Tasmanian devil and burrowing bettong. A Tasmanian devil insurance population was established in 2006 due to the threat of devil tumour disease (DFTD). Female devils were selected for contraception in 2015 and 2017 based on their genetic profile with the aim of equalizing founder representation and maximising the genetic benefit per breeding event. Suprelorin implants were ineffective in male devils. Intensive dose-response trials in female devils demonstrated that a 4.7mg implant achieved contraception for one year, while a 9.4mg implant was effective for up to two years. Implants were trialled on female devils in free-ranging enclosures and on Maria Island, which demonstrated that treatment was reversible and had no effect on access to food, social status, movements, survival and body weight. This novel use of contraceptives therefore also enables animals to be group housed, thus reducing operational costs and maintaining wild behaviours and relationships. The 4.7 mg Suprelorin implants were also trialled as a potential tool for managing a locally overabundant burrowing bettong population at the Arid Recovery reserve. There were no negative side effects, yet efficacy could not be proven.

Prey may recognize and respond to predatory cues based on a period of co-evolution or life experience with a predator. When faced with a novel predator, prey may be naive to the threat posed and/or unable to respond effectively, making them highly susceptible to predation. Burrowing bettongs (Bettongia lesueur) are one such species whose naivete towards introduced predators has contributed to their extinction from mainland Australia. Here, we asked whether bettongs that were predator-naive and bettongs which had been exposed to feral cats (Felis catus) for up to 2 years could discriminate between odors of a predator with which they shared no evolutionary history (feral cats), a predator with which they share a deep evolutionary history (Tasmanian devil—Sarcophilus harrisii), a novel herbivore (guinea pig—Cavia porcellus), and procedural control (a towel moistened with deionized water). We deployed scents at foraging trays and filmed bettongs’ behavior at the trays. Predator-naive bettongs’ latency to approach foraging trays and behavior did not differ between scents. Cat-exposed bettongs increased their latency to approach in the presence of animal scents compared with control, and approached predatory scents slowly and cautiously more often than herbivore and procedural control scents. Taken together, these results suggest that bettongs have not retained anti-predator responses to Tasmanian devils after 8000 years of isolation from mammalian predators but nevertheless show that bettongs exposed to predators are more wary and may be able to generalize predator response using olfactory cues. When prey encounter a novel predator, they are often naive to the threat posed and employ ineffective anti-predator responses, because they lack either evolutionary or ontogenetic experience with the predator. Determining how prey identify novel predators is important to improve the success of translocations and reintroductions. Here, we examine how exposure of predator-naive individual burrowing bettongs to predators influences anti-predator responses. By quantifying bettong responses to odors, we show that those experimentally exposed to cats increased their vigilance in response to odors from cats and Tasmanian devils. The results are consistent with the idea that prey generalize anti-predator responses based on non-specific compounds found in predatory odors, and that exposure to novel predators can improve anti-predator responses.

Organisms that are highly connected in food webs often perform unique and vital functions within ecosystems. Understanding the unique ecological roles played by highly connected organisms and the consequences of their loss requires a comprehensive understanding of the functional redundancy amongst organisms. One important, yet poorly understood, food web is that between truffle-forming ectomycorrhizal fungi and their mammalian consumers and dispersers. Mammalian fungal specialists rely on fungi as a food source, and they consume and disperse a higher diversity and abundance of fungi than do mycophagous mammals with generalist diets. Therefore, we hypothesize that mammalian fungal specialists are functionally distinct because they disperse a set of fungal taxa not fully nested within the set consumed by the combined generalist mammalian community (i.e., functional redundancy of fungal dispersal is limited). Using high-throughput sequencing, we compared the fungal composition of 93 scats from the endangered fungal specialist northern bettong (Bettongia tropica) and 120 scats from nine co-occurring generalist mammal species across three sites and three seasons. Compared with other generalist mammals, B. tropica consumed a more diverse fungal diet with more unique taxa. This aligns with our hypothesis that B. tropica performs a unique dispersal function for ectomycorrhizal truffle fungi. Additionally, modelling of mammalian extinctions predicted rapid loss of food web connections which could result in loss of gene flow for truffle taxa. Our results suggest that this system is sensitive to the extinction of highly connected specialist species like B. tropica and their loss could have consequences for ectomycorrhizal truffle fungal diversity. This suggests that the conservation of fungal specialists is imperative to maintaining ectomycorrhizal fungal diversity and healthy plant-mycorrhizal relationships.

Disease is increasingly being recognised as a risk factor in declining wildlife populations around the globe. However, there are limited protocols to assess disease risks in declining wildlife. Using epidemiological principles, we define a step-by-step framework to complete this complex and critical task. As an example, we assessed the potential role of diseases in relation to the decline of the woylie or brush-tailed bettong (Bettongia penicillata ogilbyi) in Western Australia. Between 1999 and 2006, woylie populations declined by 90%. The wildlife disease risk assessment began with a list of all known or suspected diseases to which the woylie, a species of macropod, is susceptible. This list was assessed against the spatial, temporal and demographic characteristics of the decline. Diseases causing widespread and high mortalities or debilitation leading to predation received high scores. Based on this assessment, priority diseases or pathogens for investigation identified were haemoparasites, gastrointestinal helminths, Neospora caninum, Toxoplasmosis (Toxoplasma gondii), Encephalomyocarditis virus, Macropod Orbiviruses (Wallal virus and Warrego virus), Macropod Herpesviruses (Macropodid herpesvirus 1 and 2) and Salmonella spp.

In 1933, geologist and explorer Michael Terry collected the skull of a small macropodid captured by members of his party near Lake Mackay, western Northern Territory. In 1957, this skull was described as the sole exemplar of a distinct subspecies, Bettongia penicillata anhydra, but was later synonymized with B. lesueur and thereafter all but forgotten. We use a combination of craniodental morphology and ancient mitochondrial DNA to confirm that the Lake Mackay specimen is taxonomically distinct from all other species of Bettongia and recognize an additional specimen from a Western Australian Holocene fossil accumulation. B. anhydra is morphologically and genetically most similar to B. lesueur but differs in premolar shape, rostrum length, dentary proportions, and molar size gradient. In addition, it has a substantial mitochondrial cytochrome b pairwise distance of 9.6–12% relative to all other bettongs. The elevation of this recently extinct bettong to species status indicates that Australia's mammal exti...

The eastern bettong (Bettongia gaimardi), a medium-sized digging marsupial, was reintroduced to a predator-free reserve after 100 years of absence from the Australian mainland. The bettong may have the potential to restore temperate woodlands degraded by a history of livestock grazing, by creating numerous small disturbances by digging. We investigated the digging capacity of the bettong and compared this to extant fauna, to answer the first key question of whether this species could be considered an ecosystem engineer, and ultimately if it has the capacity to restore lost ecological processes. We found that eastern bettongs were frequent diggers and, at a density of 0.3–0.4 animals ha−1, accounted for over half the total foraging pits observed (55%), with echidnas (Tachyglossus aculeatus), birds and feral rabbits (Oryctolagus cuniculus) accounting for the rest. We estimated that the population of bettongs present dug 985 kg of soil per ha per year in our study area. Bettongs dug more where available phosphorus was higher, where there was greater basal area of Acacia spp. and where kangaroo grazing was less. There was no effect on digging of eucalypt stem density or volume of logs on the ground. While bettong digging activity was more frequent under trees, digging also occurred in open grassland, and bettongs were the only species observed to dig in scalds (areas where topsoil has eroded to the B Horizon). These results highlight the potential for bettongs to enhance soil processes in a way not demonstrated by the existing fauna (native birds and echidna), and introduced rabbit.

Context Temperament can affect an individual’s fitness and survival if it also influences behaviours associated with predator avoidance, interactions with conspecifics, refuge selection and/or foraging. Furthermore, temperament can determine an individual’s response to novel stimuli and environmental challenges, such as those experienced through translocation. Increasing our understanding of the effect of temperament on post-translocation fitness is thus necessary for improving translocation outcomes. Aims The aim was to test whether differences in an individual’s behaviour or physiology could help predict body mass changes post-translocation in the woylie (brush-tailed bettong, Bettongia penicillata ogilbyi). In the absence of predation (due to release into a predator-free exclosure), body mass was used as a proxy for an individual’s success in securing resources in the new habitat, and therefore fitness. Methods Forty woylies were translocated from two predator-free exclosures to a larger exclosure, all in Western Australia. Behavioural and physiological measures were recorded during trapping, processing, holding, and release, and again at re-capture ~100 days post-release. Key results Translocated woylies generally increased in body mass post-translocation. This suggests that, in the absence of predation, the selected candidates were able to cope with the stress of translocation and possessed the behavioural plasticity to successfully find resources and adapt to a novel environment. The strongest predictors of body mass gain were sex, heart rate lability and escape behaviour when released (a convoluted escape path). Conclusions There was no significant difference in body mass between males and females pre-translocation but females showed greater mass gain post-translocation than did males, which could reflect greater investment in reproduction (all females had pouch young). Heart rate lability and escape behaviour are likely to reflect reactivity or fearfulness, a significant temperament trait in the context of translocation success. Implications Behavioural measures that can be easily incorporated into the translocation process – without increasing stress or affecting welfare of individuals – may hold promise for predicting the fate of translocated animals.

An accurate assessment of animal health is fundamental to disease investigation in wildlife. Blood samples (n = 609) from several populations of the endangered woylie or brush-tailed bettong (Bettongia penicillata ogilbyi), collected between March 2006 and April 2010 in Western Australia and South Australia, were used to establish hematologic reference ranges. Differences between populations, sexes, and seasons were also investigated. Significant sex differences in hematocrit, red blood cell, total white blood cell, neutrophil, lymphocyte, and eosinophil counts were evident in at least one population. Generally, males had higher hematocrit and blood cell concentrations than did females. A positive association of the erythron parameters with rainfall was also detected. The hematologic characteristics of woylie populations described in this study greatly increase knowledge of the health status in these populations. The data also represent a baseline to enable monitoring and detection of changes in the health status in these populations as well as representing a valid dataset for comparison with hematologic investigations in other macropods and marsupials.

Aim: To measure the effects of including biotic interactions on climate-based species distribution models (SDMs) used to predict distribution shifts under climate change. We evaluated the performance of distribution models for an endangered marsupial, the northern bettong (Bettongia tropica), comparing models that used only climate variables with models that also took into account biotic interactions. Location: North-east Queensland, Australia. Methods: We developed separate climate-based distribution models for the northern bettong, its two main resources and a competitor species. We then constructed models for the northern bettong by including climate suitability estimates for the resources and competitor as additional predictor variables to make climate + resource and climate + resource + competition models. We projected these models onto seven future climate scenarios and compared predictions of northern bettong distribution made by these differently structured models, using a 'global' metric, the I similarity statistic, to measure overlap in distribution and a 'local' metric to identify where predictions differed significantly. Results: Inclusion of food resource biotic interactions improved model performance. Over moderate climate changes, up to 3.0 °C of warming, the climate-only model for the northern bettong gave similar predictions of distribution to the more complex models including interactions, with differences only at the margins of predicted distributions. For climate changes beyond 3.0 °C, model predictions diverged significantly. The interactive model predicted less contraction of distribution than the simpler climate-only model. Main conclusions: Distribution models that account for interactions with other species, in particular direct resources, improve model predictions in the present-day climate. For larger climate changes, shifts in distribution of interacting species cause predictions of interactive models to diverge from climate-only models. Incorporating interactions with other species in SDMs may be needed for long-term prediction of changes in distribution of species under climate change, particularly for specialized species strongly dependent on a small number of biotic interactions.

The woylie or brush-tailed bettong (Bettongia penicillata) is a medium-sized native Australian marsupial that has undergone a dramatic decline in numbers in recent years. Trypanosome parasites have been identified in the woylie but little is known about the prevalence and clinical impact of other haemoprotozoan parasites in these marsupials. In the present study, the occurrence and molecular phylogeny of a piroplasm was studied in woylies from six different sites in Western Australia (WA). Blood samples were screened by PCR at the 18S rRNA locus and 80.4% (123/153) of the blood samples were positive for piroplasm DNA. Sequence and phylogenetic analysis of 12 of these positives identified them as Theileria penicillata, and sequencing of cloned PCR products indicated that no other species of Theileria were present. Infected woylies had a lower body weight but microscopic evaluation of the blood films indicated that T. penicillata did not appear to cause red cell injury or anaemia. Further studies are required to determine the clinical significance of T. penicillata in woylies.