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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. [ABSTRACT FROM AUTHOR]

The demographic characteristics of populations are determined by the life-history strategies of their constituent individuals. Habitat characteristics, such as the availability of key resources, shape life-history strategies; thus habitat variation may result in intraspecific variability in demography. We studied two neighbouring populations of bobucks or mountain brushtail possums Trichosurus cunninghami within a fragmented forest system. One population occurred in a forest patch that was selectively logged in the last 40 years; the other occupied narrow strips of linear roadside remnant vegetation that have not been logged for at least 100 years. Many demographic parameters of the two populations were similar, and were consistent with those described previously for a bobuck population living in continuous forest. For example, both sexes were long-lived (at least 12 years), but there were fewer males in the oldest age classes at both sites. Most females produced one young per year and reproduction was highly seasonal. Females in the oldest age classes produced young, but none of these survived to pouch emergence. There were also marked differences between our two study populations: the sex ratio of adults was equal at the forest site but female-biased (1.7:1) at the roadside site. Forest males weighed significantly less than males at the roadside site and females at both sites. The peak of births occurred more than a month later at the roadside than at the forest site. The sex ratio of roadside offspring did not differ significantly from parity; however, the sex ratio of young at the forest site was significantly male-biased (62% of young). This demographic variation may be explained by differences in habitat characteristics (particularly logging history); a detailed investigation of resource availability at the two sites is warranted. Our results highlight the importance of studying multiple populations when attempting to describe the population ecology of a species. [ABSTRACT FROM AUTHOR]

The Australian continent exhibits complex biogeographic patterns but studies of the impacts of Pleistocene climatic oscillation on the mesic environments of the Southern Hemisphere are limited. The koala (Phascolarctos cinereus), one of Australia's most iconic species, was historically widely distributed throughout much of eastern Australia but currently represents a complex conservation challenge. To better understand the challenges to koala genetic health, we assessed the phylogeographic history of the koala. Variation in the maternally inherited mitochondrial DNA (mtDNA) Control Region (CR) was examined in 662 koalas sampled throughout their distribution. In addition, koala CR haplotypes accessioned to Genbank were evaluated and consolidated. A total of 53 unique CR haplotypes have been isolated from koalas to date (including 15 haplotypes novel to this study). The relationships among koala CR haplotypes were indicative of a single Evolutionary Significant Unit and do not support the recognition of subspecies, but were separated into four weakly differentiated lineages which correspond to three geographic clusters: a central lineage, a southern lineage and two northern lineages co-occurring north of Brisbane. The three geographic clusters were separated by known Pleistocene biogeographic barriers: the Brisbane River Valley and Clarence River Valley, although there was evidence of mixing amongst clusters. While there is evidence for historical connectivity, current koala populations exhibit greater structure, suggesting habitat fragmentation may have restricted female-mediated gene flow. Since mtDNA data informs conservation planning, we provide a summary of existing CR haplotypes, standardise nomenclature and make recommendations for future studies to harmonise existing datasets. This holistic approach is critical to ensuring management is effective and small scale local population studies can be integrated into a wider species context., Competing Interests: EH is employed by Ecoplan Australia Pty Ltd. This does not alter the authors' adherence to PLOS ONE policies on sharing data and materials.

Energy demands in the platypus are likely to increase in the breeding season, which occurs from winter to early spring. Glucocorticoids, which play a major role in energy mobilisation, were measured in consecutive blood samples from free-ranging adults at approximately monthly intervals throughout the year. Glucose and free fatty acids were also measured in some samples. Plasma concentrations of glucocorticoids rose significantly during the first 30 min after capture, accompanied by a rise in free fatty acids, but no corresponding increase in glucose concentrations. We observed a strong pattern in plasma glucocorticoids in samples collected within 15 min of capture (indicative of pre-disturbance concentrations) in different phases of the annual reproductive cycle, with significantly higher levels in both males and females in the breeding season compared to the non-breeding season. These data, and the decline in tail fat stores that occur towards the end of the mating period (around October), suggest that platypus experience high-energy demands during this phase of reproduction. Plasma glucocorticoid concentrations in females sampled during the lactation period (October-February) were relatively low, and similar to those in females sampled in the non-breeding, non-lactation period (March-June). The latter requires further investigation as results may have been influenced by sampling limitations.

Mucor amphibiorum, a dimorphic fungus, causes ulcerative dermatitis and systemic infections in the platypus Ornithorhynchus anatinus in some river systems in Tasmania but apparently not in other regions of Australia. As yet there are no suitable tests for population surveys, nor for detection of internal lesions in live animals. Consequently, immunoglobulins were purified from the serum of platypuses and anti-immunoglobulin antisera were prepared in rabbits in order to develop an enzyme-linked immunosorbent assay (ELISA) for anti-M. amphibiorum antibodies. Antigens from plate-grown cultures resulted in greater signal-to-noise ratios in indirect ELISA than those from broth-grown cultures. Platypuses with clinical ulcerative dermatitis had elevated anti-Mucor antibody levels compared to apparently unaffected individuals. Seroconversion was observed in one animal coincident with the development of cutaneous ulcers. The results suggested that platypuses in affected rivers were exposed to M. amphibiorum at a higher frequency than the occurrence of clinical disease. Some platypuses from New South Wales had elevated antibody levels but these increased significantly with age suggesting exposure to cross-reactive antigens, although exposure to M. amphibiorum cannot be excluded. Further studies are warranted to determine factors that result in progression from infection to disease, the occurrence of the fungus in areas where disease has not been observed and the specificity of antigen used in ELISA.

Objective: To determine the distribution and prevalence of sarcoptic mange in wombats, particularly the common wombat (Vombatus ursinus)., Design: Questionnaire survey in two parts., Procedure: Questionnaires were distributed to biologists, rangers, animal carers and naturalists. Part 1 of the questionnaire aimed to determine the present distribution of sarcoptic mange in wombats (103 responses). Part 2 invited respondents to assess the prevalence of sarcoptic mange in wombats over a 3 month period (four responses). Information on wombats from 66 localities was received. Each locality represented an area of about 2500 km2., Results: Mange was observed at 93% of localities surveyed and Sarcoptes scabiei was present in common wombats at 52% of localities. Sarcoptic mange was highly prevalent (22%) in two common wombat populations in Victoria. Anecdotal evidence suggested that mange epizootics are sporadic, cause significant morbidity and mortality and have a substantial effect on local abundance. The respondents did not report sarcoptic mange in either northern hairy-nosed wombats (Lasiorhinus krefftii) or southern hairy-nosed wombats (Lasiorhinus latifrons)., Conclusions: Sarcoptic mange occurs in common wombat populations throughout the range of the common wombat including Tasmania and Flinders Island. While mange epizootics are sporadic, they have the potential to threaten the long-term survival of small, remnant populations.