Petaurus Breviceps Research Articles

Variability and constraint of vertebral formulae and proportions in colugos, tree shrews, and rodents, with special reference to vertebral modification by aerodynamic adaptation.

The aim of the present study is to provide the first large data set on vertebral formulae and proportions, and examine their relationship with different locomotive modes in colugos (Dermoptera), tree shrews (Scandentia), and rodents (Rodentia), which have been considered less variable because they were thought to have a plesiomorphic number of 19 thoracolumbar vertebrae. The data included 33 colugos and 112 tree shrews, which are phylogenetically sister taxa, and 288 additional skeletons from 29 other mammalian species adapted to different locomotive modes, flying, gliding, arboreal, terrestrial, digging, and semi-aquatic habitats. The following results were obtained: (1) intra-/interspecies variability and geographical variation in thoracic, lumbar, and thoracolumbar counts were present in two gliding colugo species and 12 terrestrial/arboreal tree shrew species; (2) in our examined mammals, some aerodynamic mammals, such as colugos, southern flying squirrels, scaly-tailed squirrels, and bats, showed exceptionally high amounts of intraspecific variation of thoracic, lumbar, and thoracolumbar counts, and sugar gliders and some semi-aquatic rodents also showed some variation; (3) longer thoracic and shorter lumbar vertebrae were typically shared traits among the examined mammals, except for flying squirrels (Pteromyini) and scaly-tailed squirrels (Anomaluridae). Our study reveals that aerodynamic adaptation could potentially lead to strong selection and modification of vertebral formulae and/or proportions based on locomotive mode despite evolutionary and developmental constraints. (Folia Morphol 2018; 77, 1: 44-56) Background: The aim of the present study is to provide the first large data set on vertebral formulae and proportions, and examine their relationship with different locomotive modes in colugos (Dermoptera), tree shrews (Scandentia), and rodents (Rodentia), which have been considered less variable because they were thought to have a plesiomorphic number of 19 thoracolumbar vertebrae. The data included 33 colugos and 112 tree shrews, which are phylogenetically sister taxa, and 288 additional skeletons from 29 other mammalian species adapted to different locomotive modes, flying, gliding, arboreal, terrestrial, digging, and semi-aquatic habitats. The following results were obtained: (1) intra-/interspecies variability and geographical variation in thoracic, lumbar, and thoracolumbar counts were present in two gliding colugo species and 12 terrestrial/arboreal tree shrew species; (2) in our examined mammals, some aerodynamic mammals, such as colugos, southern flying squirrels, scaly-tailed squirrels, and bats, showed exceptionally high amounts of intraspecific variation of thoracic, lumbar, and thoracolumbar counts, and sugar gliders and some semi-aquatic rodents also showed some variation; (3) longer thoracic and shorter lumbar vertebrae were typically shared traits among the examined mammals, except for flying squirrels (Pteromyini) and scaly-tailed squirrels (Anomaluridae). Our study reveals that aerodynamic adaptation could potentially lead to strong selection and modification of vertebral formulae and/or proportions based on locomotive mode despite evolutionary and developmental constraints. (Folia Morphol 2018; 77, 1: 44-56).

Scrotal stalk ablation and orchiectomy using electrosurgery in the male sugar glider (Petaurus breviceps) and histologic anatomy of the testes and associated scrotal structures

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.

Occupancy patterns of the introduced, predatory sugar glider in Tasmanian forests

AbstractIntroduced mammals pose serious threats to native island fauna, and understanding their distribution is fundamental to evaluating their conservation impact. Introduced sugar gliders (Petaurus breviceps) are the main predator of critically endangered swift parrots (Lathamus discolor) on mainland Tasmania. We surveyed sugar glider occurrence over ~800 km2 in an important swift parrot breeding area, the Southern Forests. During 4–5 visits per site, we used call broadcast of predatory owls to elicit sugar glider alarm calls and surveyed 100 sites during February/March 2016. Naïve occupancy by sugar gliders was high (0.79), as was detectability (0.52 ± 0.03 SE), resulting in a cumulative detection probability of effectively 1. Occupancy modelling indicated a positive effect of the proportion of mature forest cover on occupancy. The best model, based on AIC scores, included the proportion of mature forest cover within a 500 m radius with constant detectability. Our study revealed surprisingly high rates of occupancy of available forest habitat throughout the heavily logged study area, such that even when mature forest cover was <10%, sugar glider occupancy was >0.5; where forest cover approached 100% (i.e. in the best quality breeding habitat for swift parrots), occupancy by sugar gliders approached 1. Our results reveal that sugar gliders are widespread across the study area which may be indicative of occupancy rates elsewhere in the breeding range of the critically endangered swift parrot. As a result, the risk of predation by sugar gliders for small birds may be widespread across logged Tasmanian forests. Additional work to identify whether population densities of sugar gliders vary with forest cover (and whether this may impact predation likelihood) is critical to understanding the conservation consequences of deforestation in the breeding range of the swift parrot.

When is a native species invasive? Incursion of a novel predatory marsupial detected using molecular and historical data

AbstractAimRange 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.LocationTasmania, Australia.MethodsWe 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.ResultsWe 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 conclusionsMolecular 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.

Physiological and behavioral responses of an arboreal mammal to smoke and charcoal-ash substrate

The recent observation that torpor plays a key role in post-fire survival has been mainly attributed to the reduced food resources after fires. However, some of these adjustments can be facilitated or amplified by environmental changes associated with fires, such as the presence of a charcoal-ash substrate. In a previous experiment on a small terrestrial mammal the presence of charcoal and ash linked to food restriction intensified torpor use. However, whether fire cues also act as a trigger of torpor use when food is available and whether they affect other species including arboreal mammals remains elusive. To evaluate whether smoke, charcoal and ash can act as proximate triggers for an impending period of food shortage requiring torpor for mammals, we conducted an experiment on captive sugar gliders (Petaurus breviceps), a small, arboreal marsupial, housed in outside aviaries under different food regimes and natural ambient conditions. When food was available, fire simulation via exposure to smoke and charcoal-ash substrate caused a significant earlier start of activity and a significant decrease in resting body temperature. In contrast, only when food was withheld, did smoke and charcoal-ash exposure significantly enhance torpor depth and duration. Thus, our study not only provides evidence that fire simulation does affect arboreal and terrestrial species similarly, but also suggests that smoke and ash were presumably selected as cues for torpor induction because they indicate an impending lack of food.

PARACLOACAL GLAND CARCINOMA IN A SUGAR GLIDER (PETAURUS BREVICEPS)

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.

Artificial tree hollow creation for cavity-using wildlife – Trialling an alternative method to that of nest boxes

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.

Lactococcus petauri sp. nov., isolated from an abscess of a sugar glider.

A strain of lactic acid bacteria, designated 159469T, isolated from a facial abscess in a sugar glider, was characterized genetically and phenotypically. Cells of the strain were Gram-stain-positive, coccoid and catalase-negative. Morphological, physiological and phylogenetic data indicated that the isolate belongs to the genus Lactococcus. Strain 159469T was closely related to Lactococcus garvieae ATCC 43921T, showing 95.86 and 98.08 % sequence similarity in 16S rRNA gene and rpoB gene sequences, respectively. Furthermore, a pairwise average nucleotide identity blast (ANIb) value of 93.54 % and in silico DNA–DNA hybridization value of 50.7 % were determined for the genome of strain 159469T, when compared with the genome of the type strain of Lactococcus garvieae. Based on the data presented here, the isolate represents a novel species of the genus Lactococcus, for which the name Lactococcus petauri sp. nov. is proposed. The type strain is 159469T (=LMG 30040T=DSM 104842T).

Can field trials improve the design of road‐crossing structures for gliding mammals?

AbstractGliding 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.

Pulmonary hyalinosis in captive sugar gliders ( Petaurus breviceps).

Pulmonary hyalinosis is an idiopathic, typically incidental lesion of old dogs, characterized by multifocal aggregates of epithelioid and multinucleate macrophages that surround periodic acid-Schiff (PAS)-positive hyaline material in airways. Lung lesions resembling pulmonary hyalinosis were observed in 6 captive adult sugar gliders ( Petaurus breviceps; 5 females and 1 male) in a retrospective review of 18 autopsied animals. Clinical signs for 3 of the sugar gliders included lethargy, tachypnea, and dyspnea. At autopsy, 5 of 6 animals had comorbid lesions that were the primary cause of death. Gross pulmonary lesions were characterized by mildly firm, discolored, vaguely nodular areas of parenchyma. Histologic examination of the lung revealed granulomatous inflammation with intracellular and extracellular amphophilic hyaline bodies within alveoli and airways. Hyaline bodies were positive for PAS and oil red O staining, blue via crystal violet staining, and displayed birefringence under polarized light, similar to findings in dogs with pulmonary hyalinosis.

Effect of nest cavity morphology on reproductive success of a critically endangered bird

ABSTRACTPopulation limitation is the outcome of cumulative and synergistic processes that act on species over multiple spatial scales. Tree cavity dependent animals are good case studies for exploring processes that potentially limit populations across multiple scales. Fine-scale cavity characteristics have important consequences for predator exclusion and fecundity, while broad-scale processes (food or habitat availability) can determine population viability. We considered the relative importance of cavity morphology in limiting the breeding success of a critically endangered secondary cavity nesting bird that is severely affected at broad scales by nest predation. Swift Parrots (Lathamus discolor) select nest cavities where the minimum entrance diameter is positively associated with cavity depth, floor diameter and maximum entrance diameter. These cavity characteristics are adaptive because they exclude native predators by physically preventing access to the nest chamber; only one introduced nest predator is able to overcome this passive nest defence. Introduced Sugar Gliders (Petaurus breviceps) could prey on Swift Parrot nests irrespective of nest cavity morphology. We found no effect of cavity morphology on the number of eggs laid or fledglings reared by Swift Parrots. This suggests that fine-scale nest cavity characteristics do not influence the nest success of Swift Parrots beyond their effectiveness in excluding native Tasmanian predators.

Analisis Kebutuhan Nutrien dan Efisiensi Penggunaan Pakan Bubur Formulasi pada Oposum Layang (Petaurus breviceps Waterhouse, 1839)

ABSTRACT The aims of the research was to analyze nutrient requirements, performance, and feed efficiency of porridge formulation on sugar gliders (Petaurus breviceps) based on daily feed intake and digestibility. The research was conducted at the Small Mammal Captivity of Zoology Division, Research Center for Biology, Indonesian Institute of Sciences (LIPI) Cibinong, Bogor. Descriptive method was used in this experiment, with 14 days of preliminary period and 70 days (10 weeks) of data collection. The research materials were 16 sugar gliders aged about 3-5 months and randomly divided into 2 treatments ie. 8 heads were given porridge formulation I (P0 - control treatment) and 8 heads were given porridge formulation II (PI) plus superworm 2 times a week. Estimation of feed digestibility done in vivo with the method of the feces total collection. Variables of this experiment are daily feed intake, nutrient requirement, total digestible nutrients (TDN), daily weight gain, and feed efficiency. The feedstuff of the porridge formulation consist of siamese banana (Musa sp.), watermelon (Citrullus lanatus), sweet potatoes (Ipomoea batatas), grape (Vitis vinifera), pear (Pyrus pyrifolia), boiled egg yolk, baby porridge, calcium, honey, boiled chicken meat, and superworm (Zophobas atratus). The results showed dry matter intake was 5.82 g/head / day or 29.31 g/head / day BB0.75 (P0) and 7.31 g/head/day or 34.16 g/head/day BB0.75 (PI). The average of body weight gain was 0.55 g / head / week (P0) and 0.73 g/head/week (PI) with feed efficiency ratio was 1.36% (P0) and 1.43% (PI). The PI treatment of porridge formulation II has improved the performance of sugar gliders in captivity. Keywords: Daily feed intake, weight gain, porridge formulation, sugar gliders, performance

The occurrence and relative abundance of small terrestrial mammals on Theda Station in the Northern Kimberley, Western Australia

Significant gaps in knowledge currently exist regarding the small mammal fauna of the Northern Kimberley (NOK) bioregion. Theda Station is a previously unsurveyed pastoral lease in the NOK. The aim of the current study was to determine the presence of small mammals (non-volant, <2 kg) on Theda Station and to compare these findings with those recently obtained on the adjacent Doongan Station. Between 2006 and 2014, 226 site surveys were conducted across 69 sites, with over 26 000 trap-nights encompassing a range of habitats. Thirteen of the 27 small mammal species known to occur in the NOK were detected. Four species (Pseudomys nanus, Rattus tunneyi, Zyzomys argurus and Sminthopsis virginiae) were common, five (Pseudomys delicatulus, Pseudantechinus ningbing, Dasyurus hallucatus, Isoodon macrourus and Petropseudes dahli) were detected less frequently, and four (Leggadina lakedownensis, Hydromys chrysogaster, Planigale maculata and Petaurus breviceps) were occasionally recorded. Our study provides important baseline data for small mammals in this region. It highlights the lack of detailed knowledge of both the presence of, and temporal fluctuations in, the region’s small mammal fauna. This study supports a non-uniform distribution of the small mammal fauna across the NOK, with Theda Station lying within a transition zone between the high rainfall rugged coastal and near-coastal areas and the lower rainfall areas of the east.

Projected direct and indirect effects of climate change on the Swift Parrot, an endangered migratory species

Assessing future changes in the suitability of the climate niche for interacting species across different trophic levels can identify direct and indirect effects of climate change that may be missed using single-species approaches. We use ensembles of species distribution models based on a dynamically down-scaled regional climate model to project the future suitability of climate for the Swift Parrot (Lathamus discolor), its primary food and habitat resources (Tasmanian Blue Gum (Eucalyptus globulus) and Swamp Gum (E. ovata)), and an introduced nest predator, the Sugar Glider (Petaurus breviceps). These results are combined with layers representing mature forest and fire danger to identify locations that may act as refuges for the Swift Parrot from fire, deforestation and predation under baseline and future climates. Almost a quarter of the nesting habitat of Swift Parrots is projected to become climatically unsuitable by the end of the 21st century, but large areas may remain climatically suitable for both Swift Parrots and their food trees. However, loss of forests and the presence of Sugar Gliders are likely to limit the availability of high-quality habitat. Offshore islands that the Sugar Glider is unable to colonise or where future climate is not projected to be suitable for the Sugar Glider may be the only places, in the near future, where the Swift Parrot will be protected from nest predation by this introduced species.

Concurrent Adrenocortical Carcinoma and Hepatocellular Carcinoma with Hemosiderosis in a Sugar Glider (Petaurus breviceps)

A 15-year-old intact female sugar glider (Petaurus breviceps) presented for a 3-day history of diarrhea and weight loss despite an excellent appetite. Upon physical examination under manual restraint, the animal was determined to be emaciated with a palpable lcm diameter, firm, and irregular abdominal mass. Following 72 hours of supportive and palliative treatment (including oral antibiotics and glucocorticoids) with no clinical response, the owner elected euthanasia and approved antemortem diagnostics for teaching purposes. A complete blood count revealed a moderate regenerative anemia, mild leukopenia, and thrombocytopenia. A significant number of sideroleukocytes were noted upon examination of a blood smear, along with platelet clumps. Plasma biochemical analysis showed moderate hypoproteinemia, moderate hypoalbuminemia, mild hypokalemia, and elevated total bilirubin. Mild hypernatremia and hyperchloremia were also present. An abdominal ultrasound confirmed the presence of a large hypoechoic abdominal mass, which appeared to be associated with the liver. Whole-body radiographs did not assist in reaching an antemortem diagnosis because of poor abdominal serosal detail secondary to severe emaciation. Postmortem examination and histopathology provided a definitive diagnosis of concurrent hepatocellular carcinoma and adrenocortical carcinoma with no evidence of metastases. Hemosiderin pigment accumulation was noted within macrophages and hepatocytes.

Isolation and characterization of a novel type of rotavirus species A in sugar gliders (Petaurus breviceps).

To estimate the risk of interspecies transmission of rotavirus species A (RVA) from exotic pets to other mammalian species, the prevalence of RVA in sugar gliders (Petaurus breviceps) was investigated. RVAs were detected in 10 of 44 sugar gliders by reverse transcription (RT)-semi-nested PCR. These viruses were classified as G27P[3] and G27P[36] genotypes, with G27 and P[36] being new genotypes as assigned by the Rotavirus Classification Working Group. To characterize sugar glider RVA in detail, one strain, RVA/SugarGlider-tc/JPN/SG385/2012/G27P[36] (SG385-tc), was isolated. All of the genes of the strain were classified as new genotypes (G27-P[36]-I19-R10-C10-M9-A20-N11-T13-E17-H12). The enterotoxin domain in NSP4, which is important for the induction of diarrhoea, was conserved between SG385-tc and previously reported mammalian strains, suggesting the potential of sugar glider RVA to cause diarrhoea in mammalian species. In fact, seven out of nine suckling mice inoculated orally with 3.9 × 104 f.f.u. of strain SG385-tc had diarrhoea and the 50 % diarrhoea-inducing dose (DD50) of strain SG385-tc in suckling mice was 1.2 × 104 f.f.u. Our findings suggest that sugar glider RVA is infective to and possibly pathogenic in other mammalian species.

Promiscuous pollination of Australia’s baobab, the boab, Adansonia gregorii

Australia’s native baobab, Adansonia gregorii (F.Muell., Malvaceae: Bombacoideae) is the only baobab outside the African continent. Baobabs of the African continent have shades either of red, orange and yellow coloured flowers and are pollinated by insects, especially by hawkmoths of the Sphingidae family, or have white flowers and are pollinated by small mammals (e.g. bats and lemurs). In contrast, the Australian baobab, with white, erected flowers, was found to be mostly pollinated by hawkmoths. It is possible that for this white-flowered species, small mammals play a role in pollination. Therefore, the aim of the study was to identify major pollinators of the Australian baobab. Motion cameras were used in December 2013 and ground observations were performed in the flowering season of 2015–2016 to observe (potential) pollinators. Results show observations of hawkmoths and other insects, birds and sugar gliders (Petaurus breviceps) pollinating the flowers. The major pollinator found in this study was, however, the black flying fox (Pteropus alecto): it was observed foraging in groups and consuming the anthers of the Australian baobab flowers. Pollination by megabats, as the black flying fox, could have played an important role in the evolution of the white, erect flower of Australian baobabs.

Dealing with uncertainty in landscape genetic resistance models: a case of three co-occurring marsupials.

Landscape genetics lacks explicit methods for dealing with the uncertainty in landscape resistance estimation, which is particularly problematic when sample sizes of individuals are small. Unless uncertainty can be quantified, valuable but small data sets may be rendered unusable for conservation purposes. We offer a method to quantify uncertainty in landscape resistance estimates using multimodel inference as an improvement over single model-based inference. We illustrate the approach empirically using co-occurring, woodland-preferring Australian marsupials within a common study area: two arboreal gliders (Petaurus breviceps, and Petaurus norfolcensis) and one ground-dwelling antechinus (Antechinus flavipes). First, we use maximum-likelihood and a bootstrap procedure to identify the best-supported isolation-by-resistance model out of 56 models defined by linear and non-linear resistance functions. We then quantify uncertainty in resistance estimates by examining parameter selection probabilities from the bootstrapped data. The selection probabilities provide estimates of uncertainty in the parameters that drive the relationships between landscape features and resistance. We then validate our method for quantifying uncertainty using simulated genetic and landscape data showing that for most parameter combinations it provides sensible estimates of uncertainty. We conclude that small data sets can be informative in landscape genetic analyses provided uncertainty can be explicitly quantified. Being explicit about uncertainty in landscape genetic models will make results more interpretable and useful for conservation decision-making, where dealing with uncertainty is critical.

Small terrestrial mammals on Doongan Station, in the Northern Kimberley bioregion, Western Australia

There are significant gaps in knowledge of the small terrestrial mammals (<2 kg) in the Northern Kimberley bioregion (NOK). There have been no known extinctions of small mammals in the NOK, despite broad-scale declines being observed across much of northern Australia. The few studies in the NOK have focussed largely on three major national parks and NOK islands and thus may not be fully representative of the region. Mammal surveys were undertaken on Doongan Station, a pastoral property adjacent to these national parks to determine the presence/absence of small mammals. Five species were found to be common (Pseudomys nanus, P. delicatulus, Rattus tunneyi, Zyzomys argurus and Sminthopsis virginiae), two species were detected less frequently (Leggadina lakedownensis and Isoodon macrourus), and four species were scarcely detected (Melomys burtoni, Hydromys chrysogaster, Planigale maculata and Dasyurus hallucatus). Two species were detected only opportunistically outside of the survey effort (Petropseudes dahli and Petaurus breviceps). The trap success was consistently low, with levels in most years being below those regarded as critically low elsewhere in northern Australia.

Detection of pathogenic Yersinia enterocolitica in pet Djungarian hamsters in Japan.

The prevalence of Yersinia enterocolitica (Y. enterocolitica) and Yersinia pseudotuberculosis was examined in 151 pet animals including 108 rodents, 39 rabbits and four sugar gliders from 13 pet stores in the Yamaguchi Prefecture, Japan. Y. enterocolitica serogroup O:3 biotype 3 negative for the Voges-Proskauer reaction (O:3/3 variant VP-) was isolated from five Djungarian hamsters (Phodopus sungorus) raised at the same pet store. These pathogenic Y. enterocolitica isolates carried the virulence genes, yadA, ail and virF, and were shown to be clonal by pulsed-field gel electrophoresis with NotI digestion. This is a first report of pathogenic Y. enterocolitica O:3/3 variant VP- in pet Djungarian hamsters in Japan.