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Digging animals perform many ecosystem functions, including soil turnover and vectoring fungi, particularly mycorrhizal fungi. However, these animals are also susceptible to the impacts of urbanisation, resulting in altered ecosystem processes. Some digging mammals, such as the omnivorous quenda (Isoodon fusciventer), a medium-sized marsupial bandicoot endemic to southwestern Australia, persist in urban landscapes and may play important roles as fungal vectors. This paper examines the fungal community in quenda scats from natural vegetation remnants within a fragmented urban landscape to ask: are quenda acting as vectors for a functionally diverse fungal community?; what fungal functional types are being vectored?; and does remnant size impact fungal species richness and composition vectored by quenda? We sequenced 53 scat samples collected from remnants and found that quenda disperse a functionally diverse fungal community, with 31% of the molecular operational taxonomic units (OTUs) putatively mycorrhizal. Fungal OTU richness was greatest in scats from smaller remnants due to higher mean relative abundance of saprotrophs, pathogens and yeasts. Fungal OTU richness of ectomycorrhizal fungi, critical for plant growth, were found at a higher abundance in larger remnants. Fungal composition was affected by remnant size, type and condition of vegetation, and soil type. Our results indicate that maintaining digging mammal populations within urban landscapes may assist with dispersal of fungi that facilitate fungal-plant interactions, contributing to ecosystem health. These results are important to understand the complex ecological implications of urbanisation, and how remaining mammals are critical in maintaining ecosystem processes within the urban land-use matrix.

Cities can provide important habitat for wildlife conservation. Many species do not make much use of anthropogenic resources, but instead are largely reliant on natural habitat remaining within a matrix of urban development, and are engulfed by encroaching housing development. Understanding which factors influence their presence and activities will allow us to manage these habitat remnants for biodiversity conservation. To this aim, we carried out a field survey recording evidence of quenda (Isoodon obesulus fusciventer) foraging digs over 106 reserves managed by the City of Mandurah, the fastest growing regional city in Australia. We identified vegetation extent and condition as primary factors correlated with the presence of quenda digging activity. In addition, the extent of canopy cover and amount of woody debris are important habitat variables to quenda, while there was a negative correlation with access to the reserves by domestic dogs (Canis familiaris). Although we included a range of urbanisation measures in the analyses (including the amount of roads nearby to each reserve, the distance to roads and the distance to buildings), none were correlated with quenda digging activity. This study indicates that quenda can persist in the urban landscape despite human activities, but highlights the importance of protected bushland reserves for their conservation.

Despite increased worldwide popularity of keeping reptiles as pets, we know little about hematologic and biochemical parameters of most reptile species, or how these measures may be influenced by intrinsic and extrinsic factors. Blood samples from 43 wild-caught pythons (Morelia spilota imbricata) were collected at various stages of a 3-yr ecological study in Western Australia. Reference intervals are reported for 35 individuals sampled at the commencement of the study. As pythons were radiotracked for varying lengths of time (radiotransmitters were surgically implanted), repeated sampling was undertaken from some individuals. However, because of our ad hoc sampling design we cannot be definitive about temporal factors that were most important or that exclusively influenced blood parameters. There was no significant effect of sex or the presence of a hemogregarine parasite on blood parameters. Erythrocyte measures were highest for pythons captured in the jarrah forest and at the stage of radiotransmitter implantation, which was also linked with shorter time in captivity. Basophil count, the only leukocyte influenced by the factors tested, was highest when the python was anesthetized, as was globulin concentration. Albumin and the albumin:globulin ratio were more concentrated in summer (as was phosphorous) and at the initial stage of radiotransmitter placement (as was calcium). No intrinsic or extrinsic factors influenced creatinine kinase, aspartate aminotransferase, uric acid, or total protein. This study demonstrates that factors including season, location, surgical radiotransmitter placement, and anesthetic state can influence blood parameters of M. s. imbricata. For accurate diagnosis, veterinarians should be aware that the current reference intervals used to identify the health status of individuals for this species are outdated and the interpretation and an understanding of the influence of intrinsic and extrinsic factors are limited.

Current theory predicts that larger-bodied snakes not only consume larger prey (compared with smaller individuals), but may also have a different range of prey available to them due to their thermal biology. It has been argued that smaller individuals, with lower thermal inertia (i.e. faster cooling rates at nightfall when air temperature falls and basking opportunities are limited), may be thermally restricted to foraging and hunting during the day on diurnally active prey, and have reduced capacity to hunt crepuscular and nocturnal prey species. This predictive theory was investigated by way of dietary analysis, assessment of thermal biology and thermoregulation behaviour in an ambush forager, the south-west carpet python (Morelia spilota imbricata, Pythonidae). Eighty-seven scats were collected from 34 individual pythons over a 3-year radiotelemetry monitoring study. As predicted by gape size limitation, larger pythons took larger prey; however, 65% of prey items of small pythons were represented by nocturnally active, small mammals, a larger proportion than present in larger snakes. Several measures of thermal biology (absolute body temperature, thermal differential of body temperature to air temperature, maximum hourly heating and cooling rates) were not strongly affected by python body mass. Additionally, body temperature was only influenced by the behavioural choice of microhabitat selection and was not affected by python body size or position, suggesting that these behavioural choices do not allow smaller pythons to vastly increase their temporal foraging window. By coupling dietary analysis, measures of body temperature and behavioural observations of free-ranging animals, we conclude that, contrary to theoretical predictions, a small body size does not thermally restrict the temporal window for ambush foraging in M.s.imbricata. An ontogenetic or size-determined switch from ambush feeding to actively foraging on slower prey would account for the differences in prey taken by these animals. The concept of altered foraging behaviour warrants further investigation in this species.

Understanding microhabitat requirements for species vulnerable to anthropogenic threats can provide important information to conservation managers. This may be particularly true for ectotherms, where behaviour and physiology (e.g. digestion, responsiveness and activity patterns) are strongly influenced by thermal conditions of microhabitat retreat sites. Retreat sites selected by south-west carpet pythons (Morelia spilota imbricata) were identified through radiotracking 46 pythons over 3 years. Tree hollows appear to be a very important resource for pythons: 61% (22 of 36 individuals tracked over winter) used tree hollows as retreat sites (56% of all observations in winter), and remained in hollows for an average of 124 ± 49 (range 34 to 210) days. If pythons did not use tree hollows over winter, they found refuge in one of four alternative microhabitats: low vegetation cover (26% of winter observations), ground cover (10%), on tree branches (6%) or in hollow logs on the ground (2%). We tested whether tree hollows provide a thermally distinct environment compared with alternative microhabitats, but found no difference in minimum, average, maximum or range of temperatures recorded between microhabitats. When within tree hollows over winter, pythons had colder daily average and maximum body temperatures (cf. pythons that used other microhabitats), but this did not give them an energy saving (in terms of body condition scores). Pythons ate very little over winter and we predict that animals sequestered within tree hollows do not access prey at this time. Tree hollows provide a critical refuge over winter when python body temperature is low, and their responsiveness is limited, rendering individuals vulnerable to predation by terrestrial predators (e.g. introduced red fox). Destruction of hollows through fire, land clearing, competition with other fauna species and the significant age required for hollows to form in trees all contribute to the decline in availability of this important microhabitat.

Objective To investigate the expulsion of radiotransmitters in snakes and modify the surgical technique for coelomic implantation to prevent its occurrence. Design To enable monitoring of snakes for an ecological study, radiotransmitters were implanted in 23 south-west carpet pythons (Morelia spilota imbricata) using the standard surgical technique. In a further 23 pythons we used a refinement of the technique, which anchored the tracking device, using non-dissolvable sutures, to the snake's rib-cage. We also investigated the potential mechanisms for expelling the radiotransmitters in one snake that underwent an exploratory coeliotomy. Results Of the initial group of snakes, 12 (52%) expelled the radiotransmitter between 4 days and 3 years post implantation. In the later group, which underwent the refined technique of implantation, none of the radiotransmitters was expelled and no adverse responses were observed. Conclusion An appropriately sized radiotransmitter anchored to the rib-cage of the snake will prevent expulsion of the device and appears to be well tolerated. Non-attachment of the tracking device enables it to migrate along the length of the body, particularly during feeding and reproduction. Caudal positioning of the transmitter's antenna provides a possible pathogenesis for expulsion into the cloaca.

For animals sparsely distributed across a landscape, finding and identifying a receptive female during a short breeding period can be a challenge for males. Many snakes appear to rely on the production of sex-specific pheromones to synchronise the timing of reproductive behaviour. The rare Australian south-west carpet python (Morelia spilota imbricata) displays non-aggressive mating aggregations of up to six males around a receptive female, suggesting that males are responding to some chemical signal that enables multiple males simultaneously to identify and locate the female. We investigated chemoreceptive response (tongue-flicking) of 10 male pythons under laboratory conditions to 12 (randomly ordered) treatments each presented for three minutes. Cutaneous chemicals (dissolved in hexane solvent) were collected on cotton buds from the skin of six female pythons and male responses to these were compared with six control treatments. Male pythons produced a greater number of tongue flicks during the first minute of each trial, with fewer in minutes 2 and 3. Male chemoreceptive response in the third minute varied significantly between treatments and was only maintained for trials presenting cutaneous chemicals collected from the three relatively largest female pythons. This experiment suggests that male carpet pythons can use chemoreception to obtain information about their social environment, identifying pheromone cues from large, potentially fecund females. This ability would be adaptive for male mate-selection behaviour and is likely to also reduce costs of searching behaviour.