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The success of carnivorous mammals is determined not only by their ability to locate and kill prey, but also their efficiency at consuming it. Breaking large prey into small pieces is challenging due to the strong and tough materials that make up a carcass (e.g. hide, muscle, and bone). Carnivores therefore require a diverse suite of prey-processing behaviours to utilise their catch. Tasmanian devils are Australia’s only large marsupial scavengers and have the ability to consume almost all of a carcass. To determine how they do this we analysed 5.5 hours of footage from 21 captive and wild devils feeding at carcasses. We documented 6320 bouts of 12 distinct prey-processing behaviours, performed at frequencies that varied throughout feeds and between groups. The time point in the feed influenced the types of behaviours used. This is likely due to changing prey size, as different techniques appear better suited to handling whole carcasses or large pieces (pulling and pinning) or smaller pieces (holding and manipulating). Group size impacted the frequency of social pulling behaviours, which increased with the number of animals. Our findings highlight the range of prey-processing behaviours performed by scavenging devils when handling, breaking down, and consuming a carcass. The devils’ repertoire shares similarities with large carnivores that handle and consume whole carcasses as well as small carnivores that are adept in grasping and handling smaller prey.

Globally, predator aversion training has assisted naive prey species to learn to evade introduced predators, improving translocation success. Eastern barred bandicoots (Perameles gunnii; hereafter ‘bandicoot’) are extinct on mainland Australia due to habitat loss and introduced predators, and are the focus of a long-term captive breeding and reintroduction program. Our trials showed that captive bandicoots failed to recognise cat (Felis catus) scents as belonging to a predator, suggesting prey naivety towards cats. We trialled five stimuli to elicit short-term fear behaviour in bandicoots. An automatic compressed air spray and automatic bin lid were most effective. We coupled these stimuli with cat urine during predator aversion training and presented them to bandicoots on three occasions. Bandicoots learnt to avoid the area containing cat urine, suggesting bandicoots are capable of learning new behaviours rapidly. Six trained and five untrained captive bandicoots where released onto Summerland Peninsular, Phillip Island (with cat densities at 1.1 cats/km2). Both had high survival and recapture rates 7 months after release. Training endangered species to avoid introduced predators could assist with long-term species recovery.

Mammalian carnivores rely on their sharp teeth to effectively kill and consume prey. However, over time this causes wear and breakage that alters tooth shape, reducing their effectiveness. Extreme tooth wear and damage is especially prevalent in species that scavenge carcasses, like the Tasmanian devil (Sarcophilus harrisii), which are well known for their voracious appetites and ability to consume almost all of a carcass, including bone. In this study, we comprehensively describe tooth wear in captive and wild devils to look for differences in the patterns and rate of wear between these environments. To do this we surveyed tooth condition in skulls from 182 wild and 114 captive devils for which age was estimated using canine over-eruption. We found the types of tooth wear documented were the same in captive and wild devils, but captive animals have less severe wear than wild devils of the same estimated age. There was no difference in the proportion of captive or wild individuals with broken canine or molar teeth; however, breakage occurred at a younger age in wild devils. Although not considered anomalous or harmful, this indicates a difference in the way teeth are being used and/or the foods consumed between captive and wild devils. We hypothesize how these results relate to differences in diet or behavior that may stem from their various feeding environments, for example, higher quality food (fresh, whole, and yet to be scavenged carcasses) provided to captive devils likely causes less wear. Further, we support management options that closely replicate wild diet items and behaviors suitable for a long-term insurance population.

The eastern wallaroo (Osphranter robustus robustus) is a large macropodid commonly found in New South Wales and Queensland, but rare in Victoria. Previously only known in north-east Victoria from a resident population near Suggan Buggan, and isolated records

We determined patterns of burrow use by juvenile platypuses (Ornithorhynchus anatinus) in their natal home range, and evaluated associations between burrows and vegetation. Between March 2015 and March 2017, we captured seven juvenile platypuses along a 3-km stretch of Badger Creek, Victoria and fitted them with radiotransmitters. We recorded the locations of animals in their burrows daily while transmitters were attached (range: 14–132 days). Juveniles used 74 different burrows, with each using 11 ± 2 burrows. Overall, 65% of burrows (48) were used once, 22% (16) were used between 2 and 9 times (moderate-use), and 13% (10) were used frequently (> 10 times). No juveniles dispersed during the monitoring period (14–132 days). Although some association was observed between burrow use and particular vegetation communities, vegetation was not a strong factor driving site selection of burrows. Use of multiple burrows may allow juveniles to avoid competition with conspecifics, reduce exposure to ectoparasites, and develop shelter-seeking behavior. Juvenile platypuses remained in their natal home range, where conditions are likely to be good because they supported recent breeding, while completing their growth and development prior to dispersal.

Devising non-invasive techniques to maintain natural behaviours and increase breeding success of captive populations is a high priority in the conservation of endangered species. Allowing animals to choose their own mates not only preserves behaviours that are essential for successful release and re-establishment of wild populations, but could increase the number and genetic quality of young and genetic viability of a population. It can also decrease stress and aggression between mates and reduce the likelihood of fighting, injuries and deaths. Despite this, mate choice often remains underused in captive breeding programs. Additionally, the use of freezing and storing scents to determine a female’s mate choice between institutions has not been examined. We examined the effects of familiarity between mates, male age, preferences of relatives, and freezing scents on female mate choice and breeding success in a colony of a small marsupial, the stripe-faced dunnart (Sminthopsis macroura). Experiments were conducted using olfactory cues from males placed in the female’s enclosure. Pairings based on mate choice resulted in significantly more pregnancies per female and per oestrus cycle (p = 0.001), and a shorter time to parturition (p = 0.017), than females paired on pedigree alone, though there was no significant difference in litter sizes (p = 0.380). Familiarity between mates did not affect female preferences (P > 0.50), but significantly decreased levels of aggression and minor injuries between mates (p = 0.042). Male age similarly did not affect a female’s preference (P > 0.18). Females paired with the choice of their sisters had high breeding success (73.7%), suggesting that mate choices can be applied to related animals. Freezing a male’s scent for up to 40 days at −20 °C did not affect female choice and may be used for enabling mate preference between captive breeding institutes. The results show that female mate choice can significantly increase breeding success in a captive marsupial breeding colony and may be a powerful tool for a variety of endangered species breeding programs.

Captive breeding is fundamental to recovery programs for many endangered species. Most programs seek to maximise retention of genetic variation and minimise inbreeding risk by assigning individuals to pre-determined pairings, but the reproductive outcomes of such pairings are often poor. There is evidence that pairing individuals in captivity that are instead genetically and behaviourally compatible can result in improved reproductive success, and that the resulting offspring perform better when released into the wild. Evidence is also mounting that such compatible outcomes can be achieved by allowing female mate choice. We investigated whether the reproductive success of captive endangered eastern barred bandicoots (Perameles gunnii) improved when females were permitted to choose their mate. Over a 21 day period, we allowed females to simultaneously evaluate two males that were unrelated to the female via interaction through perforated clear acrylic barriers, which permitted visual, auditory and olfactory, but not physical, contact. We determined female preferences by measuring how much time they spent interacting with each male, and whether they showed behavioural signs of receptivity. We then paired females with either their preferred or non-preferred male, and recorded the time to conception and number of pouch young produced. Based on the interaction choice trials, females paired with preferred males were significantly more likely to produce young (p = 0.03). These preferred pairings also resulted in earlier conception of young than non-preferred pairings (p = 0.008). These findings could improve productivity of the eastern barred bandicoot breeding program and, more generally, support the incorporation of mate choice into conservation breeding programs for other species wherever practical.

Opportunities for studying platypus courtship and mating behaviours in the wild are limited due to the nocturnal and cryptic nature of this species. We report on platypus courtship and mating behaviour from a successful breeding program at Healesville Sanctuary, Victoria, in which platypuses were held as either breeding pairs or trios over seven years. Behaviour was recorded daily on infrared cameras resulting in over 80,000 h of footage that was analysed for activity periods, and courtship and mating behaviours including non-contact and contact courtship, mating and avoidance. Our aims were to describe and quantify courtship and mating interactions between males and females, and to determine if either sex controlled the initiation and continuation of the behaviours. From our observations, we describe a new courtship behaviour, non-contact courtship, which constituted the majority of all mating season interactions between males and females. The time between first and last appearance of a courtship and mating behaviour was 41.0 ± 6.6 days, with the females showing behavioural receptivity for 29.6 ± 5.1 days. Female platypuses used three evasive strategies in relation to approaches by males: avoidance, flight and resistance. Females controlled the duration of 79% of encounters using resistance. For the first time, two females were seen competing with each other over access to the male platypus in their enclosure and for nesting material. Time investment in courtship and mating behaviours was a poor indicator of receptivity and breeding success, and we suggest that breeding failure is more likely to be associated with failure of fertilisation, nest building, embryonic development or incubation. We describe how female platypuses demonstrate evasiveness and control of courtship and mating behaviours, and the importance of providing these opportunities in captivity to promote successful breeding.

Simple Summary In the summer of 2019–2020, a series of more than 15,000 bushfires raged across Australia in a catastrophic event called Australia’s Black Summer. An estimated 3 billion native animals, and whole ecosystems, were impacted by the bushfires, with many endangered species pushed closer to extinction. Zoos Victoria was part of a state-led bushfire response to assist wildlife, alongside government, non-government organisations, and key partners. Here, we detail the role of Zoos Victoria in wildlife triage and welfare, threatened species evacuation and recovery, media and communications, and fundraising during and after the fires. We provide case studies on the triage, care, release, and monitoring of injured koalas (Phascolarctos cinereus); the evacuation and return of endangered eastern bristlebirds (Dasyornis brachypterus) and brush-tailed rock wallabies (Petrogale penicillata); and the development of nutritionally suitable supplementary food and emergency feeding of critically endangered mountain pygmy-possums (Burramys parvus). We share our strategies for future resilience and readiness for similar catastrophic events, as well as the development of triage protocols, emergency response kits, emergency enclosures, captive breeding programs, and nature-based healing for communities directly affected by the fires. We hope that by outlining these contributions from a zoo-based conservation organisation, other zoos and wildlife organisations, both nationally and internationally, may be assisted or encouraged to commit resources and build expertise to assist wildlife in catastrophic events. Abstract Modern zoos are increasingly taking a leading role in emergency management and wildlife recovery. In the face of climate change and the predicted increase in frequency and magnitude of catastrophic events, zoos provide specialised expertise to assist wildlife welfare and endangered species recovery. In the 2019–2020 Australian bushfire season, now called Australia’s Black Summer, a state government-directed response was developed, assembling specialised individuals and organisations from government, non-government organisations, research institutions, and others. Here, we detail the role of Zoos Victoria staff in wildlife triage and welfare, threatened species evacuation and recovery, media and communications, and fundraising during and after the fires. We share strategies for future resilience, readiness, and the ability to mobilise quickly in catastrophic events. The development of triage protocols, emergency response kits, emergency enclosures, and expanded and new captive breeding programs is underway, as are programs for care of staff mental health and nature-based community healing for people directly affected by the fires. We hope this account of our response to one of the greatest recent threats to Australia’s biodiversity, and steps to prepare for the future will assist other zoos and wildlife organisations around the world in preparations to help wildlife before, during, and after catastrophic events.

We investigated predator–prey interactions between cane toads (Rhinella marina) and native water rats (Hydromys chrysogaster), where toads are novel prey. We show that wild water rats preferentially targeted larger toads, and consumed specific non-toxic organs only. Rats either rapidly learned these behaviours, or adapted them from hunting native frogs.

Maternal care in platypuses has never been rigorously studied due to the difficulty in locating and accessing nesting burrows. Here we describe the maternal behaviour of a captive female platypus and the growth and development of her offspring over 11 breeding seasons. We located a nesting burrow and inserted a camera to record the activity and behaviour of the female and her offspring. We also measured the female’s food intake during lactation. The ages of the offspring were assigned to developmental milestones including opening of the eyes and development of pelage. Twins (n=4) were left alone for periods longer than 24h by the mother at an earlier age than single nestlings (n=2). The dietary energy intake of the breeding female was more than double that of non-lactating females in the last month of lactation, indicating the large energy requirements of milk production. The mean age of young at emergence from the burrow was 128±1 days and in 60% of nestlings emergence occurred after weaning. This suggests a rapid transition from a completely milk-based diet to a diet of aquatic macroinvertebrates. The techniques we developed have allowed us to study maternal care in platypuses and the development of nestlings, both of which were previously only poorly understood.

Captive breeding followed by reintroduction to the wild is a common component of conservation management plans for various taxa. Although it is commonly used, captive breeding can result in morphological changes, including brain size decrease. Brain size reduction has been associated with behavioral changes in domestic animals, and such changes may negatively influence reintroduction success of captive-bred animals. Many marsupials are currently bred in captivity for reintroduction, yet the impacts of captive breeding on brain size have never been studied in this taxa. We investigated the impacts of a few generations (2-7) of captive breeding on brain volume in the stripe-faced dunnart (Sminthopsis macroura), and found that captive breeding in a relatively enriched environment did not cause any changes in brain volume. Nonetheless, we advocate that great care be taken to provide suitable husbandry conditions and to minimize the number of captive generations if marsupial reintroduction programs are to be successful.

Camera trapping has evolved into an efficient technique for gathering presence/absence data for many species; however, smaller mammals such as rodents are often difficult to identify in images. Identification is inhibited by co-occurrence with similar-sized small mammal species and by camera set-ups that do not provide adequate image quality. Here we describe survey procedures for identification of two small, threatened rodent species – smoky mouse (Pseudomys fumeus) and New Holland mouse (P. novaehollandiae) – using white-flash and infrared camera traps. We tested whether observers could accurately identify each species and whether experience with small mammals influenced accuracy. Pseudomys fumeus was ~20 times less likely to be misidentified on white-flash images than infrared, and observer experience affected accuracy only for infrared images, where it accounted for all observer variance. Misidentifications of P. novaehollandiae were more common across both flash types: false positives (>0.21) were more common than false negatives (

Females show mate preferences for males that are genetically dissimilar to themselves in a variety of taxa, but how females choose these males is not clearly understood. In this study, we examined the effects of olfactory stimuli and genetic relatedness on female mate choice in a small carnivorous marsupial, the agile antechinus (Antechinus agilis), during two breeding seasons. Captive female antechinus in oestrus were provided with a combination of male urine and body scent from two novel males, one more genetically similar and one more dissimilar to the females, in a Y-maze olfactometer. Genetic relatedness between females and pairs of males was determined using highly polymorphic, species-specific, microsatellite markers. Females consistently chose to visit the scents of males that were genetically dissimilar to themselves first, spent significantly more time near the source of those scents and showed more sexual and non-exploratory behaviours near those scents. These data demonstrate that chemosensory cues are important in mate choice in the agile antechinus and that females prefer males that are genetically dissimilar to themselves.

Marsupial research, conservation, and management can benefit greatly from knowledge about glucocorticoid (GC) secretion patterns because GCs influence numerous aspects of physiology and play a crucial role in regulating an animal's response to stressors. Faecal glucocorticoid metabolites (FGM) offer a non-invasive tool for tracking changes in GCs over time. To date, there are relatively few validated assays for marsupials compared with other taxa, and those that have been published generally test only one assay. However, different assays can yield very different signals of adrenal activity. The goal of this study was to compare the performance of five different enzyme immunoassays (EIAs) for monitoring adrenocortical activity via FGM in 13 marsupial species. We monitored FGM response to two types of events: biological stressors (e.g., transport, novel environment) and pharmacological stimulation (ACTH injection). For each individual animal and assay, FGM peaks were identified using the iterative baseline approach. Performance of the EIAs for each species was evaluated by determining (1) the percent of individuals with a detectable peak 0.125–4.5 days post-event, and (2) the biological sensitivity of the assay as measured by strength of the post-event response relative to baseline variability (Z-score). Assays were defined as successful if they detected a peak in at least 50% of the individuals and the mean species response had a Z ⩾ 2. By this criterion, at least one assay was successful in 10 of the 13 species, but the best-performing assay varied among species, even those species that were closely related. Furthermore, the ability to confidently assess assay performance was influenced by the experimental protocols used. We discuss the implications of our findings for biological validation studies.

Anecdotal observations of captive platypuses (Ornithorhynchus anatinus) suggest that they show a seasonal preference for particular foods, but this has never been rigorously measured. This study aimed to determine seasonal food preferences and energy consumption of captive platypuses so that better protocols for maintaining platypuses in captivity can be developed. Seven platypuses were fed an ad libitum diet with all food items weighed in and out of tanks. Food items were analysed for energy, fats, carbohydrates, proteins, vitamins and minerals. Platypuses preferred less mobile prey (mealworms, earthworms and fly pupae) over highly mobile prey (crayfish). There was no significant seasonal change in preference for different dietary items, which is more likely to be driven by prey behaviour. Crayfish contributed the largest percentage (mass) consumed and was highly nutritious. While the relative percentage of items in the diet did not change seasonally, the quantity eaten did. The mean energy intake of platypuses was 921 kJ kg–1 day–1 and varied seasonally, being lowest during the breeding season (810 kJ kg–1 day–1) and highest in the postbreeding season (1007 kJ kg–1 day–1). These changes were associated with preparation and recovery from the breeding season. We conclude that the platypus diet is influenced by nutrition and seasonal factors as well as by prey behaviour. This knowledge will contribute to improving the husbandry and management of platypuses, which are widely recognised as difficult to maintain in captivity.

The platypus nesting burrow, where females lay eggs and rear their young, has not been well studied. We have little knowledge of its structure and the process of construction. This study aimed to investigate nesting behaviour of breeding females and to describe the structure and features of the burrow. We used infrared cameras to record behaviour of captive breeding female platypuses during the nest-building period, over nine years. After the young had become independent, we excavated 11 nesting burrows and mapped their structural features. Nesting behaviour was observed 7–15 days after mating and was an indicator of gravidity. Females invested an average of 8 h 18 min over 3.5 nights, gathering and transporting wet nesting material to their burrows. The nests were composed mostly of native mat-rush leaves. Nesting burrows varied in length from 3.2 to 10.4 m. They contained narrow tunnels, ‘pugs’ of backfilled earth, dead ends, multiple entrances and a chamber at the end that contained the nest. Appropriate nesting sites and nesting materials must be provided to female platypuses for captive breeding programs to succeed.

Our research investigates the effects of genetic relatedness between mates and male size on female mate choice in the agile antechinus (Antechinus agilis). Females were provided with a simultaneous choice between one large and one small male, with a minimum 5 g (~20% of male weight) difference between males, in specially designed mate-choice enclosures. Genetic relatedness between males and females was determined using highly polymorphic, species-specific, microsatellite markers. Male size did not influence mate choice, with approximately equal numbers of large and small males chosen. Females chose males that were more genetically dissimilar to themselves significantly more times and showed significantly more sexual and non-exploratory behaviours near the genetically dissimilar males. The results show that, when free female mate choice is possible, female agile antechinus choose males on the basis of genetic relatedness, rather than male size.

It has been predicted, on the basis of morphological and behavioural evidence, that female feathertail gliders (Acrobates pygmaeus) will mate with multiple males within a single oestrus and that multiple paternity may occur in their litters. To determine whether feathertail glider litters are sired by multiple males, DNA collected from 10 litters and their mothers was tested for hereditary polymorphisms. The techniques used to evaluate paternity included AFLP (amplified fragment length polymorphisms), RAPD (randomly amplified polymorphic DNA) and RAMP (randomly amplified microsatellite polymorphisms) analyses and microsatellite markers. Although most genetic techniques produced only monomorphic bands, analyses with AFLPs indicated that multiple paternity did occur in six of eight litters, confirming that multiple mating within a single oestrous period occurs in this species. Results further indicated that mothers care for young other than their own. On the basis of their high testes-to-bodyweight ratio, male-biased sexual size dimorphism and multiple paternity in litters, sperm competition is considered highly likely to occur in this species.