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Australian arboreal mammals are experiencing significant population declines, particularly due to land clearing and resulting habitat fragmentation. The squirrel glider, Petaurus norfolcensis, is a threatened species in New South Wales, with a stronghold population in the Lake Macquarie Local Government Area (LGA) where fragmentation due to urbanization is an ongoing problem for the species conservation. Here we report on the use of squirrel glider mitochondrial (385 bp cytochrome b gene, 70 individuals) and nuclear DNA (6,812 SNPs, 87 individuals) markers to assess their population genetic structure and connectivity across 14 locations sampled in the Lake Macquarie LGA. The mitochondrial DNA sequences detected evidence of a historical genetic bottleneck, while the genome-wide SNPs detected significant population structure in the Lake Macquarie squirrel glider populations at scales as fine as one kilometer. There was no evidence of inbreeding within patches, however there were clear effects of habitat fragmentation and biogeographical barriers on gene flow. A least cost path analysis identified thin linear corridors that have high priority for conservation. These areas should be protected to avoid further isolation of squirrel glider populations and the loss of genetic diversity through genetic drift.

Hepatic toxicosis caused by copper accumulation has been reported in most domestic species, as well as multiple small exotic mammals, including ferrets, fruit bats, and sugar gliders. The purpose of this study was to determine the signalments, clinical presentations, and histologic findings associated with hepatic copper accumulation in sugar gliders based on post-mortem histologic findings and retrospective analysis of reported antemortem clinical signs. Sugar gliders with histologic evidence of various hepatopathies were identified within the Northwest ZooPath archive. Sections of formalin-fixed, paraffin-embedded hepatic samples were stained for copper, and copper deposition was graded semiquantitatively. The prevalence of copper accumulation in the evaluated hepatopathies was 28%. Copper deposition was seen in all individuals with icterus and non-ataxia neurologic signs. Grossly, individuals with hepatic masses and nodules were 5.50 times more likely to have hepatic copper accumulation. Sugar gliders with biliary hyperplasia were 16.20 times more likely to have copper accumulation while all individuals with cholestasis had hepatic copper accumulation. The results of this study indicate that hepatic copper accumulation is frequently identified in post-mortem evaluation of sugar gliders with hepatopathy. Copper accumulation is frequently noted in individuals with icterus, neurologic abnormalities, hepatic masses, biliary hyperplasia, and cholestasis. This study details the prevalence of hepatic copper accumulation in sugar gliders and illustrates associations between copper hepatotoxicosis and other hepatic diseases.

Population monitoring of arboreal mammals should be informed by estimates of detection probabilities from different methods. We employed trapping and spotlighting across 36 transects to detect the squirrel glider (Petaurus norfolcensis). Repeat surveys were conducted over five sessions. We used multi-method occupancy to compare these methods. The probability of detection did not differ between one night of spotlighting (0.23 ± 0.04, mean ± s.e.), or one night of trapping (0.22 ± 0.03). Trapping continued for three nights, which led to the probability of detection rising to 0.41 ± 0.04. Spotlighting was only conducted once per session. These methods would require equivalent effort when conducted over three nights. Further investigation is required to compare this and other methods such as camera trapping and spotlighting with thermal cameras.

Multiple studies have described the anatomy and function of the external ear (pinna) of bats, and other placental mammals, however, studies of marsupial pinna are largely absent. In bats, the tragus appears to be especially important for locating and capturing insect prey. In this study, we aimed to investigate the pinnae of Australian marsupials, with a focus on the presence/absence of tragi and how they may relate to diet. We investigated 23 Australian marsupial species with varying diets. The pinnae measurements (scapha width, scapha length) and tragi (where present) were measured. The interaural distance and body length were also recorded for each individual. Results indicated that all nectarivorous, carnivorous, and insectivorous species had tragi with the exception of the insectivorous striped possum (Dactylopsila trivirgata), numbat (Myrmecobius fasciatus), and nectarivorous sugar glider (Petaurus breviceps). No herbivorous or omnivorous species had tragi. Based on the findings in this study, and those conducted on placental mammals, we suggest marsupials use tragi in a similar way to placentals to locate and target insectivorous prey. The Tasmanian devil (Sarcophilus harrisii) displayed the largest interaural distance that likely aids in better localization and origin of noise associated with prey detection. In contrast, the smallest interaural distance was exhibited by a macropod. Previous studies have suggested the hearing of macropods is especially adapted to detect warnings of predators made by conspecifics. While the data in this study demonstrate a diversity in pinnae among marsupials, including presence and absence of tragi, it suggests that there is a correlation between pinna structure and diet choice among marsupials. A future study should investigate a larger number of individuals and species and include marsupials from Papua New Guinea, and Central and South America as a comparison., We investigated the pinnae of marsupials, with a focus on the presence/absence of tragi and how it may relate to diet. Of the 23 Australian marsupial species studied, only nectarivorous, carnivorous, and insectivorous species had tragi. The results suggest a correlation between pinnae structure and diet choice among marsupials.

Despite a large body of research, little agreement has been reached on the ultimate driver(s) of geographic variation in body size (mass and/or length). Here we use skull length measurements (as a surrogate for body mass) from five Australian marsupial species to test the primary hypotheses of geographic variation in body size (relating to ambient temperature, productivity, and seasonality). We used a revised articulation of Bergmann’s rule, wherein evidence for thermoregulation (heat dissipation or heat conservation) is considered supportive of Bergmann’s rule. We modeled the skull lengths of four Petaurid glider species and the common brushtail possum (Trichosurus vulpecula) as a function of indices of ambient temperature, productivity, and seasonality. The skull length of Petaurus ariel, P. notatus, and the squirrel glider (P. norfolcensis), increased with increasing winter minimum temperature, while that of T. vulpecula decreased with increasing summer maximum temperature. The skull length of P. ariel decreased with indices of productivity, falsifying the productivity hypothesis. Only P. ariel met the hypothesis of seasonality, as skull length increased with increasing seasonality. Thermoregulation was the most consistently supported driver of geographic variation in body size, as we found evidence of either heat conservation or heat dissipation in four of the five species examined. We found the geographic range of the individual species and the climate space in which the species occurred was integral to understanding the species’ responses to climate variables. Future studies should use specimens that are representative of a species’ entire geographic range, encompass a variety of climatic regions, and use consistent methodologies and terminology when testing drivers of geographic variation in body size.

Petaurus breviceps and Petaurus norfolcensis have produced hybrids in captivity, however there are no reported cases of Petaurus hybridisation in the wild. This study uses morphological data, mitochondrial DNA, and nuclear genome-wide SNP markers to confirm P. breviceps breviceps × P. norfolcensis hybridisation within their natural range on the central coast of New South Wales, Australia. Morphological data identified a potential hybrid that was confirmed with next-generation sequencing technology and 10,111 genome-wide SNPs. Both STRUCTURE and NewHybrid analyses identified the hybrid as a P. norfolcensis backcross, which suggests an initial F1 hybrid was fertile. The mitochondrial DNA matched that of a P. b. breviceps, indicating that a P. b. breviceps female initially mated with a P. norfolcensis male to produce a fertile female offspring. Our study is an important example of how genome-wide SNPs can be used to identify hybrids where the distribution of congeners overlaps. Hybridisation between congeners is likely to become more frequent as climate changes and habitats fragment, resulting in increased interactions and competition for resources and mates.

A morphological description of the sugar glider's (Petaurus breviceps) tongue was obtained from five individual sugar gliders and analysed under a scanning electron microscope and a light microscope using four methods of staining. The tongue has a noticeably elongated structure with three regions: apex, corpus and radix. Transition to the corpus is indicated by the sulcus medianus linguae and the frenulum on its ventral surface. The dorsal tongue displayed a raised mucous membrane manifesting as a type of papillae. Filiform papillae were differentiated into two subtypes: brush-like papillae, with a short base splitting into 5-6 processes; and flower bud filiform papillae that are shorter and wider than the former, and divided into a single main process and 4-5 secondary processes. Fungiform papillae with 1-2 taste buds are interspersed between filiform papillae and absent on the radix. Conical papillae cover the lateral margin of the corpus and increase in size when closer to the radix. Vallate papillae-three in number-are arranged as a triangular structure, with the middle papillae pointing towards the root of the tongue. A continuous groove wrapped around each papilla with several taste buds is found on its lateral surface. Two of the vallate papillae are located symmetrically on each side and are much smaller than the most caudal middle vallate that is directed posteriorly. A positive reaction using separate staining with periodic acid-Schiff and Alcian blue (pH 2.5) showed Weber's glands and von Ebner's glands appearing beneath the papillae, mainly on the muscle layer of the radix. Different reactions to the stains indicated that Weber's gland contains sialomucin and/or sulfomucin, whereas von Ebner's gland consists of serous cells secreting glycogen and/or neutral mucin. The collagen structure was identified using Masson's trichrome stain in the two bottom layers of the tongue from the apex, decreasing gradually towards the radix.

Sciurus norfolcensis Kerr, 1792 (Figs 93-95) Sciurus norfolcensis Kerr, 1792: 270. COMMON NAME. — Squirrel Glider. CURRENT NAME. — Petaurus norfolcensis (Kerr, 1792). See Jackson & Groves (2015: 112). COLLECTOR/S. — No data. COLLECTION LOCALITY. — No data. COMMENT. — Probably observed near Port Jackson (Sydney), New South Wales, Australia. COLLECTION DATE. — Between 20 June and 18 November 1802. SPECIMEN NUMBER/S. — No data. ILLUSTRATIONS. — Illustrated by Lesueur – Muséum d’Histoire naturelle du Havre, Inv. no. 80278 (Fig. 93; skull, second from left), Inv. no. 80087 and 80088 (Figs 94; 95; one living animal)., Published as part of Jackson, Stephen M., Jansen, Justin J. F. J., Baglione, Gabrielle & Callou, Cécile, 2021, Mammals collected and illustrated by the Baudin Expedition to Australia and Timor (1800 - 1804): A review of the current taxonomy of specimens in the Muséum national d'Histoire naturelle de Paris and the illustrations in the Muséum d'Histoire naturelle du Havre, pp. 387-548 in Zoosystema 43 (21) on page 407, DOI: 10.5252/zoosystema2021v43a21, http://zenodo.org/record/5142972, {"references":["KERR R. 1792. - The Animal Kingdom, or zoological system, of the celebrated Sir Charles Linnaeus; Class 1. Mammalia: containing a complete systematic description, arrangement, and nomenclature, of all the known species and varieties of the Mammalia, or animals which give suck to their young; being a translation of that part of the Systema Naturae, as lately published, with great improvements, by Professor Gmelin of Goettingen. Together with numerous additions from more recent zoological writers, and illustrated with copper plates. J. Murray & R. Faulder, London. Volume 1. https: // www. biodiversitylibrary. org / page / 38664031","JACKSON S. M. & GROVES S. M. 2015. - Taxonomy of Australian Mammals. CSIRO Publishing, Melbourne, 529 p."]}

Arboreal gliders are vulnerable to habitat fragmentation and to barriers that extend their glide distance threshold. Habitat fragmentation through deforestation can cause population isolation and genetic drift in gliding mammals which in turn can result in a loss of genetic diversity and population long-term persistence. This study utilised next generation sequencing technology to call 11, 292 genome-wide SNPs from 90 adult sugar gliders (Petaurus breviceps). Samples were collected from 12 locations in the Lake Macquarie Local Government Area (New South Wales), with two of these locations west of the Pacific Motorway, a potential major barrier to their dispersal. Overall, Lake Macquarie sugar gliders appeared to have high levels of gene flow and little genetic differentiation, however spatial least cost path analyses identified the Pacific Motorway as a barrier to their dispersal. This Motorway is still relatively new (< 40 years old), so man-made crossing structures should be erected as a management priority to mitigate any long-term effects of population isolation by assisting in the dispersal and gene flow of the species. This study provides further insight into the sugar glider after it was classed as three separate species in 2020 and could potentially be used as a model for its threatened congener in the area, the squirrel glider (Petaurus norfolcensis).

Fear may elicit behavioural and physiological responses in animals. We conducted a pilot study aiming to reduce bird nest predation in Tasmania by the introduced Sugar Glider (Petaurus breviceps) by broadcasting calls of predatory owls. We designed a solar‐powered, automated weatherproof stereo for long‐term call broadcast in a forest environment. This device may have useful applications in other environments where long‐term call broadcast is required in remote field conditions. Call broadcast did not reduce the likelihood of Sugar Glider nest predation on either active bird nests or artificial nests baited with farmed quail eggs. If we elicited fear in Sugar Glider individuals with call broadcast, this fear did not result in behavioural changes that could be exploited to achieve the conservation objective of lower predation.

Postmortem examination of an 8-year-old intact female sugar glider euthanized for end-stage neoplasia revealed a large mass in the mammary gland, masses in the liver, and a few small masses in the lung. Histologic evaluation of the lesions revealed hepatocellular carcinoma, mammary gland adenocarcinoma, and pulmonary granulomata associated with a trematode larva. Ribosomal RNA gene sequencing identified a diplomastid fluke, Neodiplostomum americanum. This parasite utilizes snails as first intermediate hosts and birds of prey as definitive hosts, but the complete life cycle is not known; the hosts of the intervening life stages had not been previously reported. To the authors’ knowledge, this is the first reported case of N. americanum in a sugar glider.

Widespread declines of small- to medium-sized, semi-arboreal mammals in the drier regions of Northern Australia are of global concern. These declines have been variously attributed to either disruption of available resources or increased predation pressure. We aimed to clarify causes of mammal decline in Northern Australia using a comparative methods approach, examining historical changes in the distribution of two arboreal mammals, the common brushtail possum (Trichosurus vulpecula) and the savanna glider (Petaurus ariel), and model drivers of their current abundance. We used single-season occupancy models to describe changes in the geographic range of P. ariel and T. vulpecula based on multiple-source occurrence data, from before and after 1993. We conducted spotlighting surveys in 2016 across the mesic savannas of the Northern Territory to identify environmental correlates of the current abundance of each species. Our results show that, within northwestern Australia, the geographic range (area where the probability of occupancy was ≥ 5%) has declined by 72% for T. vulpecula and 35% for P. ariel, between the historical and contemporary periods (before and after 1993, respectively). The abundance of each species varied substantially across the study area, but high T. vulpecula abundance was associated with high shrub density. We propose that areas with high shrub density are providing refuge for T. vulpecula, due to an increase in protection from predation by feral cats (Felis catus). Regardless of the driver, conservation management within Northern Australia should concentrate efforts on maintaining or increasing shrub abundance in tropical savannas. Our findings should also be viewed as an indicator of early stages of P. ariel decline and prompt targeted monitoring efforts.

A 5-year-old castrated male sugar glider (Petaurus breviceps) was referred for a 2-week history of a left fluctuant pericloacal swelling and intermittent stranguria. Ultrasound of the abdomen and pericloacal area suggested a herniation of the urinary bladder with cystolithiasis. Upon surgical exploration, the bladder was normal, and a paracloacal cyst originating from the left cloacal wall was identified. Removal of the paracloacal cyst and subsequent histopathologic evaluation confirmed a cloacal wall cyst. Recovery from surgery was uneventful and long-term follow-up revealed no complications or recurrence. This is the first reported case of a paracloacal cyst in a sugar glider. Paracloacal cyst should be considered as a differential when presented with a pericloacal mass or swelling in a sugar glider.

This study aims to determine the possibility of changes in the hair color on young sugar gliders (Petaurus breviceps) were given additional fruits in the feed. Research has been conducted in the Small Mammal Captive Breeding of Zoology Division, Research Center for Biology - LIPI, Cibinong, Bogor. Descriptive method used in this study with 10 days of preliminary and 90 days (3 months) of data collection period. The research material used is 16 young sugar gliders aged about 2-3 months, divided into 2 groups namely group I consists of 8 sugar gliders (4 male and 4 female) whose the parent is brownish brown color, while group II consists of 8 sugar gliders (4 male and 4 females) whose the parent are gray in color. Each group received 2 feeding porridge formulations T0 (control) and T1 (T0 + kepok banana (Musa balbisiana), watermelon (Citrullus lanatus), and red dragon fruit (Hylocereus polyrhizus)). T0 feed composition consists of brown rice porridge, boiled chicken eggs, honey, calcium, and water. Sugar gliders is given live superworm (Zophobas morio) every Tuesday and every Thursday is given live crickets (Gryllidae). During the observation each pair of young sugar glider is placed in a wire enclosure (60 cm x 42 cm x 42 cm) equipped with feeding box, drinking water bottle and a hammock. The results showed that the average of dry matter intake T1> T0. KII / T0 / enclosure 6 show higher of body weight gain and feed efficiency than KI / T1 / enclosure 4. The addition of fruits into the T1 diet did not show any discoloration in hair on sugar gliders in captivity. Keywords: fruits, feed intake, hair/fur color, Petaurus breviceps

A 6-year-old intact female sugar glider (Petaurus breviceps) had a swelling at the pouch region and died 8 days after presentation. At necropsy, the urinary bladder and abdominal lymph nodes were enlarged and a mass was located in the pericloacal region. Tumour infiltration was also observed in the medial iliac lymph nodes, liver, spleen, small intestine, uterus and left ovary. Histopathologically, the tumours were composed of pleomorphic histiocytes that had round or bizarre nuclei and abundant pale eosinophilic cytoplasm. Immunohistochemically, tumour cells were positive for ionized calcium-binding adaptor molecule 1 and human leukocyte antigen and negative for CD3, B lymphocyte antigen 36 and cytokeratin. Histopathological and immunohistochemical examinations confirmed a diagnosis of disseminated histiocytic sarcoma. This neoplasm has not been previously reported in a sugar glider.

Nest boxes are used to manage populations of tree-cavity dependent birds and mammals. Concerns have been raised that due to their poor insulative properties nest boxes may cause heat stress and occasionally death during summers of extreme maximum temperatures. Our study investigated whether this nest box heat stress hypothesis applies to two small cavity-dependent mammals (brush-tailed phascogales and sugar gliders). Focusing on days when ambient temperature reached ≥40 °C, we recorded: i) temperatures within occupied nest boxes, ii) temperatures within nearby unoccupied tree cavities, iii) the duration of temperatures of ≥40 °C within nest boxes, iv) whether direct mortality was observed, and v) the relative abundance of these species in nest boxes before and after a very hot summer. When ambient temperature reached ≥40 °C, nest boxes were equivalent to ambient or 1–2 °C cooler, whereas tree cavities were 3–7 °C cooler than ambient. Exposure in nest boxes to temperatures of ≥40 °C lasted an average of 2–8 h. We observed no mortality over 65 records of phascogales and 31 records of gliders in nest boxes on days when ambient reached ≥40 °C. No decline in abundance was recorded after a summer with 11 days of temperatures ≥40 °C, with each species subsequently occupying >40 nest boxes. Our observations suggest these species are tolerant of the high temperatures that occurred. Nonetheless, provision of nest boxes designed to minimise summer heating is recommended.

The loss of hollow-bearing trees is a key threat for many hollow-dependent taxa. Nesting boxes have been widely used to offset tree hollow loss, but they have high rates of attrition, and, often, low rates of usage by target species. To counter these problems, chainsaw carved hollows (artificial cavities cut into trees) have become a popular alternative, yet little research has been published on their effectiveness. We examined the usage of 150 chainsaw carved hollows by cavity-dependent fauna in the central west of New South Wales using observations from traditional inspection methods and remote cameras. Between October 2017 and April 2019, we detected 21 species of vertebrates (two reptile, one amphibian, 10 bird, and eight mammal species) inside chainsaw carved hollows, but the number of species detected was dependent on the chosen monitoring method. We detected six species inside hollows during physical inspections, whereas remote cameras detected 21 species entering hollows. Cameras detected eight species using hollows as breeding sites, whereas physical inspections detected just four species. Cameras detected two threatened mammals (squirrel glider (Petaurus norfolcensis) and greater glider (Petauroides volans)) raising young inside hollows, yet we failed to detect these species during physical inspections. For birds, the two methods yielded equivalent results for detection of breeding events. Overall, our study showed that few cavity-dependent species used chainsaw carved hollows as breeding sites. This highlights how artificial hollows are not a substitute for retaining naturally occurring hollows in large trees and revegetation programs.

Objective To provide reference values for ocular examination and diagnostics in ophthalmologically normal sugar gliders (Petaurus breviceps). To retrospectively determine the prevalence of ocular diseases in sugar gliders presenting to a single institution. Animals Ten client owned and 106 previously evaluated sugar gliders. Procedure A descriptive study evaluated sugar gliders presented to Colorado State University's Avian, Exotics, and Zoological Medicine Service (CSU-AEZ) from August-2019 to January-2020. A complete ophthalmic examination including Schirmer tear test II (STT II), phenol red threat test (PRTT), intraocular pressure (IOP) via rebound tonometry, fluorescein, and rose bengal stain was performed under anesthesia. Conjunctival aerobic culture swabs and cytology were collected prior to ophthalmic evaluation. A retrospective review of medical records of sugar gliders presented to CSU-AEZ from 2008 to 2018 for ocular disease was performed. Results Mean values ± standard deviation for selected diagnostics included the following: STT II: 2.2 ± 6.7 mm/min; PRTT: 0 ± 0 mm/15 s; IOP: 12 ± 2.6 mm Hg. Fluorescein and rose bengal staining highlighted corneal abrasions secondary to tear testing. The three most common conjunctival bacterial isolates cultured were Staphylococcus spp. (3/20, 15%), Coryneform spp. (3/20, 15%), and unidentified Gram-positive cocci (3/20, 15%). Retrospective analysis revealed ocular diseases to be the third most common abnormality resulting in sugar glider presentations (13/106, 12.3%). Conclusion This descriptive study gives reference values for IOP, conjunctival microbiology, and cytology for sugar gliders. STT II and PRTT provide little clinical value in sugar gliders. The retrospective study revealed that ocular abnormalities, often secondary to dental disease, are a common reason for presentation.

Traditional population viability analysis (PVA) does not address the degree of measurement error or spatial and temporal variability of vital rate parameters, potentially leading to inappropriate conservation decision-making. We provide a methodology of applying Bayesian network (BN) modeling to PVA addressing these considerations, particularly for species with complex stage-class structures. We provide examples of three species from eastern Australia - hip pocket frog (Assa darilingtoni), squirrel glider (Petaurus norfolcensis) and giant burrowing frog (Heleioporus australiacus), comparing traditional matrix-based PVA with BN model analyses of mean stage abundance, quasi-extinction probability, and interval threshold extinction risk. Both approaches project similar population sizes, but BN PVA gave more clearly identifiable thresholds of population changes and extinction levels. The PVA BN uniquely represents complex stage-class structures and in a single network, including variation and uncertainty propagation of vital rates, to better inform conservation management decisions.

The creation of mechanically carved tree cavities to provide supplementary shelter for hollow-dependent wildlife is increasingly popular in conservation management programs. However, there is limited empirical evidence quantifying how the features of their design and broader placement within the landscape influence use by target fauna. In this study, we took a multi-scale approach to investigating the use of chainsaw hollows (CHs) by a target native arboreal marsupial, Krefft’s Glider Petaurus notatus. We hypothesized that Krefft’s Gliders would respond to attributes of: (1) the CH itself; (2) the tree into which it was installed; and (3) the habitat within the reserve in which it was located. We monitored occupancy (over 2.7 years, using a pole camera) of 48 CHs installed in live Eucalyptus trees across multiple reserves in Melbourne, Australia, plus visitation (over ∼3 months, using camera traps) to 40 of the CHs. Mixed models were used to relate the occupancy of CHs by Krefft’s Gliders to field-collected data on various attributes of CHs at all three scales. From a total of 35,219 visitations across the 40 CHs, we recorded 13 native hollow-dependent species (five mammals, eight birds) visiting CHs. During 14 pole-camera inspections, Krefft’s Glider occupied 60% of the 48 CHs at least once, with 4% used as maternal dens during breeding. Four exotic species were also recorded visiting and/or occupying CHs. Orientation and volume both significantly affected occupancy: Krefft’s Gliders were more likely to occupy larger CHs, and those facing north and west (possibly related to microclimate). Tree-scale attributes did not affect occupancy, but Krefft’s Gliders were more likely to occupy CHs further from reserve edges, and where local density of Black Wattles (Acacia mearnsii: an important food resource) and low vegetation cover (100–200 cm above ground) was increased. Our findings show that CHs can provide supplementary shelters for Krefft’s Gliders when natural hollows are limited. Practitioners should consider both the physical characteristics of the cavity (e.g. volume) and the surrounding habitat (e.g. availability of foraging resources) to enhance the use of CHs by target species. The ongoing availability of CHs to target species will also be influenced by their use by exotic species, and potential for closure as woundwood grows. In an Australian context, a lack of knowledge about the specific features of natural hollows to which hollow-dependent fauna respond, means it is critical for policy and management to prioritize the retention of mature hollow-bearing trees.

This report describes an alternative surgical technique for performing scrotal ablation and orchiectomy in the adult male sugar glider ( Petaurus breviceps ) using electrosurgery. Eight animals from a local small mammal shelter group that presented for routine surgical castration for population control measures were included in this study. Mean surgical time was 4.37 ± 2.13 seconds. Mean anesthesia time was 12.32 ± 5.63 minutes. Mean recovery time was 8.37 ± 3.68 minutes. Mean total procedure time was 22.24 ± 5.69 minutes. No perioperative complications were reported. All animals appeared to have sufficient pain management with an analgesia and anti-inflammatory protocol using butorphanol and meloxicam. No over grooming and or self-injurious behaviors were reported by the local shelter during both the 24-hour and 14-day recheck examinations. Electrosurgery scrotal ablation and orchiectomy therefore offers an alternate route for the practicing veterinarian to perform safe and efficient castrations in male sugar gliders. Histologically, in the epididymis, 3 of the 8 sugar gliders had evidence of a well-defined region in the head, between the efferent ducts and the remaining epididymis. The lining cells differed morphologically from those constituting the remaining epithelial lining. The presence of eosinophilic vacuoles in the cytoplasm of the cells in this region suggests a secretory activity.

Aim Range expansions facilitated by humans or in response to local biotic or abiotic stressors provide the opportunity for species to occupy novel environments. Classifying the status of newly expanded populations can be difficult, particularly when the timing and nature of the range expansion are unclear. Should native species in new habitats be considered invasive pests or actively conserved? Here, we present an analytical framework applied to an Australian marsupial, the sugar glider (Petaurus breviceps), a species that preys upon on an endangered parrot in Tasmania, and whose provenance was uncertain. Location Tasmania, Australia. Methods We conducted an extensive search of historical records for sugar glider occurrences in Tasmania. Source material included museum collection data, early European expedition logs, community observation records, and peer‐reviewed and grey literature. To determine the provenance of the Tasmanian population, we sequenced two mitochondrial genes and one nuclear gene in Tasmanian animals (n = 27) and in individuals across the species' native range. We then estimated divergence times between Tasmania and southern Australian populations using phylogenetic and Bayesian analyses. Results We found no historical evidence of sugar gliders occurring in Tasmania prior to 1835. All Tasmanian individuals (n = 27) were genetically identical at the three genes surveyed here with those individuals being 0.125% divergent from individuals from a population in Victoria. Bayesian analysis of divergence between Tasmanian individuals and southern Australian individuals suggested a recent introduction of sugar gliders into Tasmania from southern Australia. Main conclusions Molecular and historical data demonstrate that Tasmanian sugar gliders are a recent, post‐European, anthropogenic introduction from mainland Victoria. This result has implications for the management of the species in relation to their impact on an endangered parrot. The analytical framework outlined here can assist environmental managers with the complex task of assessing the status of recently expanded or introduced native species.

A male sugar glider ( Petaurus breviceps ) was presented to the National Taiwan University Veterinary hospital for repeated self-mutilation of the cloacal region. After correction of husbandry deficiencies and medical management of the lesion, the condition improved but a pericloacal mass was found. Surgical removal of the mass resolved the self-mutilation, and a dorsal paracloacal gland carcinoma was diagnosed on histopathological examination. Straining to defecate and a pericloacal mass could indicate neoplasia in sugar gliders. A tumor should be differentiated from chronic inflammation, infection, paracloacal gland impaction, and hyperplasia. Surgical removal is recommended as a treatment for paracloacal gland carcinoma in sugar gliders. Further monitoring is suggested after surgical removal of the tumor.

Trypanosomiasis is generally considered an exotic tropical disease. American trypanosomiasis (Chagas' Disease) of dogs, cats, armadillos, monkeys, and small wild animals is caused by Trypanosoma cruzi. Although T. cruzi has been detected in chimpanzees and cynomolgus monkeys in captivity, and experimentally in an Australian phalanger marsupial (Trichosurus vulpecula), this is the first report of it detected in naturally infected “pet” sugar gliders (Petaurus breviceps) and African hedgehogs (Atelerix albiventris). A polymerase chain reaction-based method was used to detect T. cruzi organisms in formalin fixed paraffin embedded blocks from 3 sugar gliders and 1 hedgehog, which were previously diagnosed as T. cruzi-positive using the histopathological method. Sugar gliders and hedgehogs are fond of insects and actively seek arthropods in nightly forays. It is suspected that Triatoma was not feeding on the sugar gliders and hedgehogs, but rather were being eaten. The oral route of infection is often nonfatal and induces a carrier state in South American didelphid opossums, however sugar gliders and hedgehogs appear to be peracutely affected and infection results in death.

Tree hollow scarcity is a threat to cavity-dependent vertebrate wildlife world-wide across many landscapes. Currently, only nest boxes are commonly used to mitigate or offset lost cavity-bearing trees, with a number of shortfalls reported using this technique. There is a need to trial alternative techniques to improve artificial cavity provisions. This preliminary study investigated the use of carving hollows directly into tree trunks using chainsaws. Sixteen hollows of two simple cavity types were created in a timber production forest in south-eastern Australia. One cavity type comprised a basal entrance (38 mm in diameter) which provided a space above the entrance, intended for bats, and the other cavity type provided a space below a 38 mm or 76 mm entrance, intended for marsupials and birds. Five species used the hollows over a 15-month cavity monitoring period; feathertail glider ( Acrobates pygmaeus ) (in 75% of the hollows), brown antechinus ( Antechinus stuartii ) (75%), sugar glider ( Petaurus breviceps ) (63%), long-eared bat ( Nyctophilus sp.) (50%) and white-throated treecreeper ( Cormobates leucophaea ) (25%). Camera monitoring revealed hollow inspection after only one day post hollow creation by white-throated treecreepers and feathertail gliders, and nest building by white-throated treecreepers after three days. No hollow host tree failure occurred for either of the two hollow wall widths trialled over two years of monitoring tree stability. Wound-wood formed and partly enclosed the hollows’ faceplates over time, improving the sturdiness of the hollow and likely resulted in hollows closely resembling natural cavities. Mechanically created tree hollows have a broad application potential across many landscapes with the prospect to overcome some of the reported drawbacks of nest boxes. More research is required to document long-term performance and effectiveness of this technique.

Central to the conservation of animal species is identifying factors that influence habitat preference. General factors that operate across a species’ geographic range are of particular importance because they allow management actions to be applied when resources are limited. Local factors may also be important but require detailed study to identify. Distinguishing general from local factors is therefore key to conservation planning. Occupancy modelling was used to investigate habitat preferences in one landscape in south-eastern Australia of the regionally threatened yellow-bellied glider (Petaurus australis) (naive occupancy = 0.72) and the non-threatened sugar glider (Petaurus breviceps) (naive occupancy = 0.84). Hypotheses were tested to determine whether preferences were of general or local relevance. The habitat model with the greatest support for the yellow-bellied glider (a negative relationship with dead tree abundance) was specific to this landscape, which might suggest a local factor. This was interpreted to reflect a negative response to fire and may be an unrecognised general factor. In contrast, the best supported model for the sugar glider (a positive relationship with increasing basal area of winter-flowering trees) represented a general factor. This study suggests there is utility in evaluating habitat factors for their general relevance but this approach relies on the availability of detailed studies across the geographic range for this approach to be effective.

Constructing hollows or cavities in trees with chainsaws is an emerging approach to manage hollow-dependent species in hollow depleted landscapes. Small-scale experiments are required to refine this approach before implementing on a broad scale. We addressed two questions: i) are chainsaw hollows used by the regionally threatened brush-tailed phascogale (Phascogale tapoatafa) and the non-threatened sugar glider (Petaurus notatus), ii) do chainsaw hollows retain their integrity over time. We paired 45 chainsaw hollows with nest boxes of equivalent internal dimensions in southeastern Australia and inspected these on 20 occasions over 2.5 years. Camera traps revealed phascogales visited some cavities within hours of installation and monthly inspections revealed rapid uptake of these hollows by both target species. Overall, phascogales and sugar gliders used 32% and 84% of the chainsaw hollows respectively, and 21% and 82% of the nest boxes. We used multi-method occupancy to compare detection within the two types of cavities. Detection models that included cavity type had more support than those without. Detection of both species was substantially higher in the chainsaw hollows compared to the nest boxes. Over the 2.5-year monitoring period the faceplates of some chainsaw hollows showed signs of deformity. Callous regrowth over the faceplate was pronounced on some trees suggesting the need for periodic maintenance. Our study confirms the potential of chainsaw hollows to restore habitat for hollow-dependent mammals but highlights periodic maintenance is likely to be a feature of this approach as it is with nest boxes.

Gliding mammals are sensitive to habitat fragmentation that produces canopy gaps beyond their gliding capability. Specific structures (canopy-bridges and glide poles) are now commonly installed in large road construction projects to enable road crossing by threatened gliding mammals. However, these structures are being installed with limited understanding of how their design features influence their use. We conducted field testing of several design features (horizontal glide launch-beams at the top of poles; rope size and complexity in rope-bridges) using free-ranging gliding mammals, and scaled-down structures at two locations. Our aim was to identify preferred features to optimise structure use. This may confirm current designs or identify the need for refinement. We found that squirrel gliders (Petaurus norfolcensis) and sugar gliders (Petaurus breviceps) preferred a forward-pointing over a sideways-pointing glide beam. A single-rope rope-bridge was favoured over a mesh rope-bridge by sugar gliders but not squirrel gliders. No preference was shown by either species between mesh or ladder-style rope-bridges that differed in rope strand spacing. Large, permanently installed ladder or mesh rope-bridges commonly have single ropes connecting them to the adjacent forest. We investigated the use of a permanently installed 50-m long single-rope rope-bridge. Infra-red camera monitoring over 366 nights detected squirrel gliders on this bridge on 172 nights, common ringtail possums (Pseudocheirus peregrinus) on 144 nights and common brushtail possums (Trichosurus vulpecula) on 120 nights. This confirms acceptance of the single rope by a range of species and provides confidence in installing rope-bridges that may vary in rope size and complexity.

Millions of dollars are spent on wildlife crossing structures intended to reduce the barrier effects of roads on wildlife. However, we know little about the degree to which these structures facilitate dispersal and gene flow. Our study incorporates two elements that are rarely used in the evaluation of wildlife crossing structures: an experimental design including a before and after comparison, and the use of genetic techniques to demonstrate effects on gene flow at both population and individual levels. We evaluated the effect of wildlife crossing structures (canopy bridges and glider poles) on a gliding mammal, the squirrel glider (Petaurus norfolcensis). We genotyped 399 individuals at eight microsatellite markers to analyse population structure, first-generation migrants and parentage relationships. We found that the freeway was not a complete genetic barrier, with a strong effect evident at only one site. We hypothesise that the presence of corridors alongside the freeway and throughout the surrounding landscape facilitated circuitous detours for squirrel gliders. Installing a crossing structure at the location with a strong barrier effect restored gene flow within just 5 years of mitigation. Synthesis and applications. Our study highlights the importance of using genetic techniques not just to evaluate the success of road-crossing structures for wildlife, but also to guide their placement within the landscape. Managers wishing to reduce the effects of linear infrastructure on squirrel gliders and other arboreal mammals should aim to preserve and enhance vegetation along roadsides and within centre medians, as well as mitigate large gaps by implementing wildlife crossing structures.

Biodiversity offsetting is widely applied but its effectiveness is rarely assessed. We evaluated the effectiveness of a nest box program intended to offset clearing of hollow-bearing trees associated with a freeway upgrade in southern Australia. The offset targeted three threatened vertebrates: squirrel glider (Petaurus norfolcensis), brown treecreeper (Climacteris picumnus) and superb parrot (Polytelis swainsonii). Clearing led to the loss of 587 tree hollows and the offset was the placement of an equivalent number of nest boxes in nearby woodland (1:1 ratio). Of these, we monitored 324 nest boxes in six sample periods between 2010 and 2013, yielding 2485 individual checks of nest boxes. For the three target species, we found: (1) no records of nest box use by the superb parrot, (2) two records of the brown treecreeper (0–0.76% of accessible nest boxes used per survey period), and (3) seven records of use of nest boxes by the squirrel glider (0–2.1% of accessible nest boxes used per survey period). Rates of nest box use by the superb parrot and squirrel glider were markedly lower than rates of use of hollow-bearing trees observed in other investigations. Low levels of use by target species coupled with the extent of nest box attrition suggest the offset program will not have counterbalanced the loss of the hollow-bearing trees. We make suggestions for improving future offset programs including a greater emphasis on: (1) avoiding impacts on hollow-bearing trees; (2) offset effectiveness as a measure of compliance; and (3) using realistic offset ratios.

Nest boxes are frequently used in conservation programs for tree-cavity dependent wildlife. There is growing concern that the poor insulation properties of nest boxes may produce an ecological trap, because species may require microclimates less extreme or less variable than those experienced inside nest boxes. I investigated the fitness consequences of nest box use in a non-flying mammal. Fifty-two of 104 squirrel gliders (Petaurus norfolcensis) trapped over a 3-year period used nest boxes. Population modelling of the capture data revealed that the probability of apparent survival increased with increasing nest box use. There was no difference in breeding frequency between females that used or did not use nest boxes. There was no evidence that offspring development was hindered within nest boxes. These findings may arise because: (1) gliders could access tree hollows during extreme temperatures, (2) ambient temperatures were mild during the study, (3) gliders construct leaf nests which insulate against low temperatures in winter, and (4) gliders breed between autumn and spring when temperatures are relatively benign. The estimate of annual survival of animals using nest boxes (0.60), was equivalent to estimates at locations where squirrel gliders were either reliant on nest boxes (0.54) or on tree cavities (0.55) for shelter. Studies such as this need to be conducted on a range of species across a range of locations to better understand the influence of nest box use on non-flying mammals.

Summary Southern Squirrel Glider (Petaurus norfolcensis) populations are genetically distinct and generally found in the agricultural landscapes inland of Australia's Great Dividing Range. These populations are considered to be under greater threat of extinction than northern, coastal populations and face a unique set of environmental conditions and conservation challenges. For these reasons, we suggest that southern populations qualify as a separate evolutionarily significant unit to those from the northern, coastal segment of the range and should be managed separately. We summarize the species’ ecology specific to southern populations and relevant to management. We conduct a basic SWOT (strengths, weaknesses, opportunities, threats) analysis to highlight potential future management directions. From our review of new and existing ecological data and SWOT analysis, we outline ten points of action important for securing the future of southern Squirrel Glider populations.

This note describes the eviction of nesting White-throated Treecreepers Cormobates leucophaea from a nest box by a Sugar Glider Petaurus breviceps in central Victoria. Predation of the birds and eggs was not observed.