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The Zoology and Animal Ecology section of the conference covers a broad range of topics, ranging from the distribution of animal species and the different aspects of species' interactions with the environment to animal genetics and physiology, including behaviour, conservation and other topics where study objects are animals.

Significant phenotypic variation in plant resistance to herbivores occurs between and within many plant species. Plant secondary metabolites play a major role in conferring resistance to many herbivores, and intraspecific variation in plant resistance can be influenced by both genetic and environmental variation. The evolutionary and mechanistic processes behind variation in plant resistance in many systems is still unknown, particularly in relation to plant/mammalian herbivore interactions. In this thesis, intraspecific variation in resistance of Eucalyptus globulus to mammaJian herbivore browsing was investigated and the mechanistic and genetic basis of this variation examined. There was significant genetic variation in resistance of E. globulus to browsing by the common brushtail possum (Trichosurus vulpecula) and the red-bellied pademelon (Thylogale billardierii). Browsing damage was assessed on coppiced juvenile foliage of trees of known genetic stock grown in a common environment field trial. There was significant genetic variation in plant resistance amongst geographically distinct populations at the race, locality and family levels. These results were confirmed in a captive feeding trial where there was significant genetic variation in resistance among E. globulus localities (populations). The characteristics responsible for the intraspecific variation in resistance of juvenile coppiced E. globulus foliage were then investigated. There was significant phenotypic variation in foliage chemistry between individual plants. Sideroxylonals, a group of formylated phloroglucinol compounds (FPCs), accounted for the greatest amount of the observed variation in intake of foliage by T vulpecula. Variation in these compounds explained the significant genetic based differences in browsing resistance between different populations within E. globulus. These results may offer some evidence for the potential importance of mammalian herbivores as selective agents on the evolution of plant resistance within Eucalyptus. Hybridisation in plants offers an ideal opportunity to investigate evolutionary processes influencing plant/herbivore interactions. including, for example, the mode of inheritance of plant resistance. The inheritance of resistance to browsing by T. vulpecula and the inheritance of the defensive plant compounds of three year old juvenile E. globulus foliage were investigated using known hybrid progeny (pure parental intra-race hybrids and inter-race F1 hybrids) of two genetically differentiated geographical races (north eastern Tasmanian race and south-eastern Tasmanian race) of E. globulus. The results indicate that the F 1 hybrid was intermediate in resistance, compared to the parental hybrids, suggesting an additive pattern of inheritance of browsing resistance to T. vulpecula. In this foliage the concentration of FPCs was low and the combined effects of condensed tannins and essential oils appeared to explain the pattern of resistance of these hybrids. Effects of variability in plant genotype and in environmental conditions within a population can influence resistance of plants independently and/or can exhibit a genotype-by-environmental interaction. The effects of environmental variability (two nutrient treatments; high and low) on the genetic based expression of defensive chemistry and resistance of two E. globulus genotypes (St. Helens and Blue Gum Hill) to browsing by T. vulpecula was examined. While no significant independent genotype and environmental effects on intake of E. globulus seedling foliage were evident, there was a genotype-by-environment interaction. Genetic differences between the two populations was only expressed under the low nutrient regime. Significant independent effects of genotype and nutrient treatment were observed for primary and secondary leaf chemistry. Finally, the feasibility of using near infrared reflectance spectroscopy (NIR.S) as an accurate tool to rapidly predict the nitrogen content and the resistance to browsing by T. vulpecula of individual E. globulus trees was investigated. Two successful calibration equations were developed (one for nitrogen and one for intake (resistance)) !hat met all statistical requirements, suggesting that these models were useful in predicting nitrogen content and resistance of new E. globulus trees. Independent validation of the nitrogen calibration equation showed that the model was successful at predicting nitrogen content of new E. globulus foliage. However, independent validation of the calibration equation for intake was unsuccessful. We suggest that a change in the defensive chemical profile across seasons, resulted in poor independent validation of the intake calibration model. We discuss the importance of using independent validation when assessing the predictive power of a calibration model and argue that with refinement in specific systems, NIRS can be used as a powerful, rapid tool in predicting resistance of trees to browsing herbivores.

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This dataset supports the findings of the study titled 'Seasonal and elevational changes of plant-pollinator interaction networks in East African mountains' published in the journal Ecology and Evolution. A full description of how this dataset was obtained is found in the aforementioned manuscript https://doi.org/10.1002/ece3.10060. The attached datasets constitute three files used in this study; 1. The metadata (containing a full description of parameters). 2. The original network dataset across the different seasons, 3. R script for seasonal and elevational patterns of plant-bee networks.

The Orange-bellied Parrot is one of only two obligate migratory parrots in the world. The species is listed nationally as endangered and has been the subject of intensive study and conservation activities over the past 25 years. Reproductive and demographic data collected over this period from the wild population form the basis of this thesis. Remote breeding sites in southwestern Tasmania at Melaleuca and Birchs Inlet were used to study this species in the wild. Through deployment of up to 52 artificial nest boxes and observations of natural nests at Melaleuca it was possible to collect information on a range of reproductive success parameters over a long period, including 12 consecutive breeding seasons. In addition, the provision of up to 33 nest boxes over seven consecutive years at Birchs Inlet provided a comparison with the use of nest boxes by several competitors at Melaleuca. The use of colour-bands to identify 760 individuals from 16 different cohorts provided the means to assess a range of behavioural and demographic parameters of the species. This study confirmed the Orange-bellied Parrot has a regular migratory pattern with birds beginning to return to the breeding area on the 2nd October (plus or minus 5.1 days s.d) in each year. The first birds to return are those in their second year of life or older, while first-year adult birds begin to arrive 13 days later. The median arrival date for birds in their second year or older was the 23rd October compared with 9th November for firstyear adult birds. There was no difference between the sexes in arrival date. The mean date of last departure from Melaleuca was 5th April (plus or minus 11.1 days s.d). A total of 190 nests with known contents were studied in the wild and, of these 185 nests contained eggs and five nests contained no eggs. This study found the earliest laying date was on the 29th November and the latest was the 19th January with eggs (95%) laid during December (n = 101 eggs). Clutch size ranged from 2-6 eggs with over half of the clutches having 5 eggs and 95.3% of all clutches 4-6 eggs in size. The mean clutch size was 4.7 eggs per active nest across all years and there was no evidence the species can produce second clutches in the wild. The mean incubation period for Orange-bellied Parrot eggs was 21.4 plus or minus 0.8 days (n = 49 observed incubations). The mean dimensions of unhatched eggs was 22.9 plus or minus 0.98 mm by 18.5 plus or minus 0.67 mm (n = 99 eggs). The 185 nests with eggs studied by this work contained a total of 874 eggs. Of these 695 eggs hatched and 179 eggs failed to hatch. Of the 179 failures, 107 eggs (69.7%) were infertile, 48 eggs (26.8%) were fertile and 24 eggs (13.4%) were of unknown fertility. Of the 48 unhatched fertile eggs, 23 eggs (47.9%) were early-term failures, 15 eggs (31.2%) were mid-term failures and 10 eggs (20.8%) were late-term failures. The mean egg fertility rate for the species was calculated to be 85.6% (plus or minus 2.91 s.e). Hatching success from all eggs laid was 79.5% (i.e. 695 nestlings hatched from 874 eggs laid) with the mean hatching success across all years being 80.2%. A total of 89 nestlings died prior to fledging. Early stage deaths represented 44.9% (n = 40) of all mortalities and late stage deaths 55.1% (n = 49). The annual egg failure and nestling mortality varied across years. Of a total of 268 egg and nestling failures across all years, 66.8% (n = 179 eggs) were attributable to hatch failure and 33.2% (n = 89 nestlings) to mortality. Unhatched infertile eggs represented most (39.9%, n = 107) of all failures. Of the 190 nesting attempts, only 27 failed to produce any young. The most common cause of total nest failure was attributed to failure to hatch (44.4%, n = 12) followed by nestling deaths (37%, n = 10) and no eggs laid (18.5%, n = 5). Average brood size was 4.0 nestlings plus or minus 0.09 s.e (range = 1-6) from 173 nests with 65.9% of nests producing four (33.5%) or five (32.4%) nestlings. The majority of nests produced four fledglings with a mean fledgling brood size of 3.7 plus or minus 0.09 s.e (range = 1-6) from the 163 successful nests. Only 4.3% of successful nests produced the maximum of six fledglings. Of the 190 Orange-bellied Parrot nests studied, 85.8% (n = 163) produced fledglings. The distribution of nest productivity is presented and discussed in detail. The number of fledglings produced per breeding attempt varied between zero and six. A total of 69% of all nests produced 3-5 fledglings whereas 33% of all nests produced four fledglings. The fledging success for 12 consecutive breeding seasons was 87.2% (606 fledglings from 695 nestlings) and the mean fledging success across all years was 86.9% (plus or minus 2.47 s.e). The overall breeding success for the Orange-bellied Parrot was 69.3% (606 fledglings from 874 eggs laid). The overall reproductive output of the species was 3.3 fledglings per nest (606 fledglings from 185 nests) from an investment of 4.7 eggs laid. Egg fertility, nestling survival and fledgling survival of Orange-bellied Parrots in the wild is noticeably higher than for the captive population, and is equal to or exceeds many other Psittacidae. The reproductive success results reported here are comparable with the more common Turquoise Parrot Neophema pulchella of mainland Australia. Although the Orange-bellied Parrot has a healthy mean fecundity rate of 1.62 females/egg laying female, there was some variability between years, with a low of 0.87 females/egg laying female in 1998/99. The mean lifespan of the Orange-bellied Parrot was calculated to be 2.22 years (plus or minus 0.074 s.e, range = 0.37-11.70, N = 693) with no significant difference between male and females. Males lived on average for 2.75 years (plus or minus 0.127 s.e, range = 0.43-11.70, n = 240) and females lived on average for 2.67 years (plus or minus 0.141 s.e, range = 0.18-10.41, n = 189). The oldest male recorded was 11.70 years of age and the oldest female recorded was 10.41 years of age. This study was not able to compare the reproductive lifespan of wild Orange-bellied Parrots with captive-bred birds due to database problems or with other Psittacidae due to lack of comparable studies. The capacity to compare the wild population with captive-bred birds and other Psittacidae will greatly enhance our knowledge of the species. This work suggests the Orange-bellied Parrot does not have a strong fidelity to mates, nest site or nesting zone. This finding is contrary to previous assumptions made about the species. This study did not measure hollow availability; however, a comparison of the use of nest boxes between Birchs Inlet and Melaleuca indicates competition from introduced species may be limiting the breeding range and reproductive success. Survivorship rates of juveniles to first breeding (c. one year old), adults and both sexes were determined. Mean survivorship of juveniles over the study was 55% (plus or minus 3.2 s.e) and is within expected limits when compared to other Psittacidae. Mean survivorship of adults was 63.6% (plus or minus 2.0 s.e). There was a decreasing trend in survival rates across all cohorts from 1999 onward with average annual survival declining markedly thereafter. The reason for this decline is unclear. There was no difference in survival rate of each sex over the study. This study has significantly increased our understanding of the reproductive success and demography of the Orange-bellied Parrot. This information will reduce the level of uncertainty in the Population Viability Analysis model for the species and, in turn, increase the power of such models to assess the species status and test the effectiveness of conservation measures. Some of the results of this study have important implications for future research and conservation of the species. These are discussed, and include management of nest boxes, refinement of mark-recapture studies, population viability analysis and influence of introduced nest competitors.

In 2016, chestnut oak (Quercus prinus) trees across southern Indiana began displaying symptoms of decline disease. In the years following, widespread patches of mortality appeared on slopes and along ridges, prompting the Indiana Department of Natural Resources (IDNR) to investigate. The IDNR noted the presence of Phytophthora cinnamomi on one diseased chestnut oak, leading to the initiation of this study. Our goals were to (1) determine if P. cinnamomi contributed to the widespread decline, (2) determine what site or stand variables were associated with higher rates decline, (3) examine the growth of declining trees prior to the onset of symptoms to determine if drought contributed to decline, and (4) use Forest Service Forest Inventory and Analysis (FIA) data to examine trends in regional chestnut oak mortality. From 2021-2022, we collected thirty fine root and soil samples from declining chestnut oak trees within Morgan-Monroe State Forest, Yellowwood State Forest, and the Hoosier National Forest. Throughout these forests, we established sampling plots within declining and healthy chestnut oak stands. In each plot we recorded site, stand, and tree level variables, then collected tree cores from two or three chestnut oak trees. Fine root samples were tested for the presence of P. cinnamomi at the Purdue Pathogen and Pest Diagnostic Laboratory (PPDL) in West Lafayette, Indiana. We used binomial linear regression to test for significant (α = 0.05) relationships between site and stand variables and decline, where a binary decline or no decline was used as the response variable. Both basal area increment (BAI) and ring width index (RWI) chronologies were built separately for healthy, declining, and dead chestnut oak trees. We used a paired t-test (α = 0.05) to test for significant differences in 10-year segments of BAI between the three chronologies. Finally, we used linear regression to test for significant (α = 0.05) effects of the standardized precipitation-evapotranspiration index (SPEI) in current and previous year growing seasons on RWI. Chestnut oak mortality volume across the eastern United States was calculated using the EVALIdator tool provided by USDA-FS FIA. Associations between chestnut oak mortality recorded by FIA and several climate and topographical variables were examined using a random forest classification. Out of thirty fine root samples, only one tested positive for the presence of P. cinnamomi, indicating that this decline was not associated with the pathogen. The analysis of site and stand variables revealed a greater chance of decline on east and northeastern facing slopes, with a slight increase in decline likelihood with increasing stand density. There was significantly lower BAI in dead and declining trees long before decline symptoms began, a pattern consistent with previous drought induced declines. We observed a significant relationship between RWI and SPEI in the early growing season (June and 3-month June SPEI) and throughout almost all of the prior year’s growing season (May, June, 3-month June, 3-month July, and 3-month August SPEI). Chestnut oak mortality volume across the eastern US steadily increased from 2006-2020, indicating a region-wide increase in mortality. Our random forest classification indicated the importance of increased precipitation and precipitation timing on chestnut oak mortality. Chestnut oak decline observed in southern Indiana was induced by a series of droughts in 2005, 2007, and 2012. The greater early life BAI of chestnut oak which were impacted by decline revealed that individuals which likely prioritized stem growth over root growth were predisposed to decline and mortality from these droughts. This prioritization could be brought on by genetic differences, favoring rapid height growth in developing even-aged stands, or by an abundance of moisture availability. Our FIA analysis of mortality revealed increased mortality volume across many states from 2006-2020, and that chestnut oak mortality may be related to greater precipitation compared to historic levels. Considering these results, we suspect that chestnut oak which have recently died or are currently declining are likely individuals which lack the root system to endure repeated drought.

Cryptogam communities on coarse woody debris persist in forests regenerating after the first clearfell, burn and sow harvesting rotation due to harvest residue. The habitat disturbance dynamics in a regenerating forest is different from the natural wildfire disturbance, as is the dynamics of coarse woody debris, which, while different, also provides an opportunity for new bryophyte community development. How bryophyte communities develop in response to this new system dynamic is largely unexplored. Community development may depend on time since disturbance and/or the degree of decomposition of the coarse woody debris. For individual species and communities as a whole, it is not known which of these two effects dominates or what environmental attributes affect the resulting communities. This research attempts to tease apart these issues by examining the time dependent response of cryptogamic communities growing on coarse woody debris to first rotation clearfell, burn and sow harvesting and the relative significance of forest age and log decay progression on community succession. Subsequent to clearfelling, cryptogamic communities on coarse woody debris were compared from wet eucalypt forests of increasing age. There were significant differences in species richness and community composition between forest age and between log decay stage. Older forests were the most species rich. More individual species had significant associations with logs of intermediate decay classes than with logs of an earlier decay class. The ecology of individual species varied considerably for forest age and log decay class associations and there were distinct early, middle and late successional species identified. Forest climate measures of temperature and vapour pressure deficit were used as an indication of the variation in large scale habitat conditions over time between forests of each age and to examine the influence of habitat conditions associated with forest age on of coarse woody debris. There were significant changes over time for temperature and vapour pressure deficit where mesoclimatic conditions became less variable as forest age increased. Log moisture was a direct measure of the fine scale habitat conditions influencing cryptogam communities of coarse woody debris, especially in relation to log decay stage. Log moisture had a significant influence on bryophyte community composition over time and was important for determining the succession of cryptogamic communities when combined with mesoclimatic conditions. The effect of forest age and log decay stage on cryptogam communities of coarse woody debris suggests that both of these time dependent processes play an important role in community succession, and that the distinction between the two habitat variables may vary depending on time since clearfell, burn and sow disturbance. Fine scale community analysis revealed that at any forest age and at any decay stage there were significantly associated species. While this study has shed some light on how succession plays out in the first decades of the first clearfell, burn and sow rotation, it also suggests that communities follow a predominantly similar successional pathway as would occur in a forest regenerating after natural wildfire disturbance; however, it is likely that successive harvesting events based on 100 year rotations will result in the loss of some cryptogam species. Managing forests after clearfell, burn and sow for the development of mature stands and for actively facilitating the persistence of a range of decay stages and coarse woody debris habitat structures at the site and landscape levels may be appropriate, and the findings of this study are discussed in this context.

The five cave zone regions, ten macro-habitats and 44 micro-habitats for invertebrate species recorded from caves in two adjoining karst areas of southern Tasmania (Hastings and Ida Bay) are described. The information for these two karst areas is a sub-set of the 7,861 cave or karst area invertebrate occurrence records listed in six relationally linked tables together with 309 database queries or tabulations (contained in a Microsoft Access database) that documents collections and observations of 1,292 species from 749 occurrence sites in karst and non-karst cave areas of Tasmania. The cave related data and its content including a comprehensive micro-habitat site analysis and species taxonomy detail in a relational database is unique, making it the only cave fauna database of its kind in the world. The database provides a historical account dating back to the early 1840s when glowworms were first reported from caves in Tasmania; these are recorded along with accounts of the first cave spider and cave beetle species described in Australia. Together with anecdotal accounts from some of the early entomologists and naturalists who studied Tasmania's cave fauna, the significant role of modem day cave biologists is commended along with their contributions that have vastly expanded our knowledge base. The history of the study of cave biology is discussed, together with the development of cave fauna related ecological terms and theories or explanations for the colonisation of caves and evolution of troglomorphic characters in aquatic and terrestrial hypogean obligates. Following a brief introduction of geomorphic processes, the term \karst bio-space\" is introduced to encompass the total living space for all hypogean species in the saturated or unsaturated karst and karst-like cavities crevices and voids including caves. The concept of cave ecology is expanded to describe the five cave zone regions ten macro-habitats and the 44 micro-habitats deployed in the detailed analysis of habitat data for species in the Hastings and Ida Bay karst areas. A comprehensive explanation of the database fields is provided along with guidelines for operating the database and constructing queries to answer questions related to the diversity and ecology of Tasmanian cave species. Incorporating the most up to date and current taxonomy for cave species in Tasmania this thesis provides a detailed overview of the diversity of the most common groups of cave dwelling invertebrates and the first records of new species not previously recorded in the speleological or cave biology literature. The major species groups discussed include glowworms cave crickets land snails springtails multipedes (centipedes millipedes symphylans pauropods and onychophorans) aquatic and terrestrial amphipods and isopods bathynellacean and anaspidacean syncarids aquatic snails cave beetles and the arachnids (ticks mites pseudoscorpions harvestmen and spiders). In addition to factors related to cave morphology and hydrological influences (stream recharge or input etc.) the two predominant factors influencing the distribution of invertebrate species are the intensity of karst bio-space development and the input of organic matter its re-distribution and dilution as it is transported further into the subterranean domain. In most of the wild caves at Ida Bay this organic material is naturally derived but at Hastings where tourist caves have been developed much of the organic matter has been introduced to the cave. The source of organic input in tourist caves is varied and includes the artificial introduction of exotics in the form of tree trunks rough sawn timber and other plant matter used in the construction of stairs and fern log pathways plus the litter \"inadvertently\" placed in caves by natural processes carried in by humans or dumped as refuse in the course of the continuing development of caves for tourism. Aside from organic input the survival and distribution of cave species is dependent on a range of factors including the presence/ or absence of surface disturbance and the impacts of human use of caves or other components of the karst bio-space including groundwater. Within the karst bio-space itself there are the complexities of inter-relationships of species and predator-prey relationships within the subterranean food chain together with the presence of cave bacteria and other micro-organisms found deep within the dark zone of caves; the dependence of cave species on these micro-organisms has not been studied here in Tasmania. A proportion of the cave species are obligates totally dependent on the cave for survival and some of these species are cave adapted (troglobites or stygobites). The number of cave adapted species in Tasmanian caves generally exceeds the numbers found in most areas of mainland Australia and five caves in the study area at Hastings and Ida Bay are rated as being at world standard in the number of obligate species."

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Lack of eucalypt regeneration is a key factor in the decline of forest and woodland remnants in low rainfall agricultural regions in Australia. This thesis provides a new insight into dry forest and woodland regeneration by demonstrating how important and tightly circumscribed the eucalypt seedling regeneration niche is in these forests in Tasmania. The potential of soil water repellency to be a barrier to eucalypt recruitment and the difficulty of mimicking the regeneration niche to improve natural regeneration processes in degraded forests are highlighted. A section on management implications is included. Key to effective management of dry forests and woodlands is an understanding of the requirements and conditions that promote seed germination and seedling establishment (recruitment niche) and the persistence of lignotuberous sprouts (juvenile persistence niche). The processes of eucalypt recruitment and persistence were investigated in dry forest and woodland remnants in the Midlands of Tasmania at the scales of the stand and microsite. The work was conducted with a view to applying the results to the discipline of restoration ecology. Measurements of structural complexity at thirty remnant forest stands that were in a range of stages of decline revealed that healthy remnants contained four times the amount of eucalypt regeneration (seedlings, lignotuberous sprouts and saplings) than stands in a degraded condition and that regeneration was absent in stands of paddock trees (except for one stand in which there had been a fire). An additional lack of trees in smaller diameter size classes in both intermediate and paddock tree sites relative to the amounts shown in healthy sites implies a long-term recruitment scarcity and an unavoidable future bottleneck in the development of mature trees. The quantity of eucalypt regeneration was positively associated with other structural attributes: perennial species and life form richness; cover of vegetation 0.5-6m high; litter; dead trees; large trees; and total length of fallen logs >10cm diameter; and negatively associated with quadratic mean tree diameter at breast height. Across the thirty stands, the majority of eucalypt regeneration was in the form of lignotuberous sprouts and saplings. Only in stands burnt 2-6 years prior to the survey did newly recruited seedlings form part of the regeneration. Within these burnt sites the seedling recruitment niche differed significantly to the juvenile persistence niche (occupied by lignotuberous sprouts), while the juvenile persistence niche had characteristics similar to the general forest floor. Seedling microsites were characterised by the following: canopy gaps and ashbeds; a predominantly northerly aspect; over 220° shelter in profile; an average distance to a sheltering object of < 30cm; shelter provided by coarse woody debris (80% of seedlings sheltered by logs and branches); soil that was significantly softer and less water repellent than the forest floor; and low cover of grass. All these characteristics of seedling microsites affect moisture availability. The role of ashbeds, coarse woody debris and soil water repellency in eucalypt recruitment was further investigated. Soil water repellency (hydrophobicity) can be severe in dry eucalypt forests as hydrophobic organic compounds coat the surfaces of soil particles and this has implications for the movement and storage of water in the system. Other studies have shown that soil hydrophobicity is differentially affected by fire depending on the temperatures reached, with repellency increasing as temperature increases until a threshold is reached at which repellency is removed (approximately 260°C). Logs lying on the forest floor provide heavy fuel for intense fire which creates ashbeds. The current study showed that in ashbeds hydrophobicity was removed in surface layers but the hydrophobic layer moved lower (1-3cm) down the soil profile. The wettable surface soil zones enabled the germination of eucalypt seed and subsequent establishment of seedlings. Remaining adjacent and partially burnt coarse woody debris provided a soil moisture store (with threefold the amount of moisture in soil under logs compared to 5m away) and probably protection from microclimatic fluctuations and browsing animals. Surface soil outside of the ashbed areas was severely water repellent suggesting that soil water repellency may be a barrier to eucalypt recruitment in lightly burnt and unburnt soils. These findings were applied to restoration ecology. Patch scale restoration trials were conducted in six dry forest remnants in the Midlands of Tasmania in an attempt to mimic the eucalypt recruitment and persistence niches through the use of intense spot burns or cultivation with and without the addition of large logs. Survival of seedlings established from introduced seed and natural seed rain was variable within and among sites resulting in no treatment effects. Thus the 'Burn with the addition of logs' treatment did not successfully mimic the recruitment niche, probably because the experiment did not mimic the natural heterogeneity of hydrophobicity following wildfire. However, the survival of planted seedling was greatest in 'Cultivated with no log' treatments, which most closely resembled the juvenile persistence niche. Burning treatments did provide a relatively weed-free seed bed for over a year and surviving seedlings grew significantly better than those in cultivated treatments which quickly became infested with grassy weeds despite granular herbicide application. Survival of planted seedlings and the amount of observed germination of sown seed were each significantly correlated with the structural complexity score of the planting site with seedling survival significantly higher in sites of healthy condition. This suggests that the more degraded sites had crossed an abiotic threshold (using state and transition model terminology) that was not completely removed by the experimental restoration treatments. The early establishment of planted eucalypt seedlings was also shown to be significantly affected by species; the underlying soil water repellency of the planting plot; the proximity to an adult tree and the type of soil amelioration used in the restoration treatment but not by the presence or absence of logs. Suggestions for further work include trialling treatments that more closely mimic the recruitment niche by partially burning and retaining logs in situ rather than post burn addition; investigating the timing and intensity of weed control in cultivated treatments; testing the effects of soil water repellency amelioration through the use of wetting agents; and investigating spatial aspects of treatment patch placement.

The thesis examines various aspects of vegetation dynamics and change on subantarctic Macquarie Island over the ten years 1980 to 1990. The island is basically an elongated plateau surrounded by steep coastal slopes 100-250 meters in height. The major vegetation type on these slopes consists of tall tussock grassland dominated by the tussock-forming grass Poa foliosa, with the tall herb Stilbocarpa polaris an important accompanying species. The behaviour and distribution of these two species in the coastal slope vegetation under various disturbance conditions through time, forms the major focus of this study. The longitudinal observations of the study (involving longterm re-sampling through time) also allow the testing of an existing model of revegetation patterns on disturbed coastal slope sites which was based on a set of latitudinal observations (once-off \spatial\" sampling of time-sequence data from a series of differently aged sites). These latitudinal observations were taken at the beginning of the 1980-1990 study period. The timing of the study coincides with the first ten years after myxomatosis was first introduced into the feral rabbit population in 1978- 79 substantially reducing rabbit numbers. The effects of grazing on the coastal slope vegetation since the introduction of rabbits in the 1850's appears to have been substantial although until recently little documented. Landslipping is also a common disturbance factor affecting the coastal slope vegetation. Changes in the vegetation of 27 sites on areas affected by landslipping rabbit grazing or a combination of both were studied over the 10-year period by monitoring of fixed plots. This study was complemented by a broadscale study of vegetation change over a five kilometer section of the coastal slopes through comparison of aerial photographs taken at the beginning and the end of the study period and by a study of changes in a series of paired quadrats in relatively undisturbed vegetation over the same period. A study of seasonal growth and dieback patterns of Stilbocarpa polaris over a twelve month period and analysis of a series of observations on grazing patterns prior to 1980 provided additional insights into behaviour of Stilbocarpa polaris and effects of grazing on the coastal slopes. Through these means the effects of the various disturbance factors on the vegetation dynamics can be inferred. Since 1980 there has been an overall increase in abundance of Poa foliosa and Stilbocarpa polaris especially the former on the coastal slopes. This can be linked to the substantial reduction of rabbit numbers after 1978-79 to a level amenable to control but not eradication by myxomatosis. It could also possibly be linked to climatic warming. Vegetation succession on areas disturbed by landslipping or rabbit grazing will eventually progress to a Poa foliosa-dominated vegetation with Stilbocarpa polaris as a co-dominant or subsidiary 4.ominant in the absence of further grazing disturbance and/ or slope instability. Continuation of selective grazing on disturbed areas on the coastal slopes however will suppress the development of Poa foliosa and to a lesser extent Stilbocarpa polaris and an increase of grazing pressure will favour the development and maintenance of short grassland/herbfield vegetation. The conclusions from the longitudinal study largely verify those of the latitudinal study although minor modifications are justified by the new data."

Limited understanding of the ecology of ground-dwelling invertebrates in Tasmania has hampered our ability to assess the adequacy of forest management. This thesis documents the distributions of ground-dwelling beetle assemblages in managed, wet eucalypt forests of southern Tasmania, and explores the response of beetles to ecological gradients caused by riparian influences near small streams (since retained riparian corridors are a major conservation tool), and edge effects from recently clearfelled logging coupes. Extensive pitfall trapping using replicated transects at four sites was employed to compare the beetle fauna between five habitats: young logging regeneration, the interior of upslope mature forest, the riparian-upslope transition in mature forest interior, and across coupe edges (both into upslope mature forest and into streamside reserves). Data screening ensured that the primary transect design, which employed traps positioned at unequal distances within transects, was unlikely to produce patterning in beetle distributions attributable to spatial autocorrelation or pitfall trap depletion. \ \ Beetles responded to riparian influences, showing subtle shifts in assemblage composition, and generally reduced abundance or species richness nearer to streams. However, site differences outweighed riparian effects. Beetles assemblage composition differed substantially between young logging regeneration and mature forest: several species were identified as indicators of each habitat. Beetles responded more strongly to edge effects than to riparian influences. Depth of edge influence extended ~ 22 m into unlogged non-riparian forest, but further into streamside reserve edges (up to ~ 65 m). Four beetle species, Choleva TFIC sp 01 (Leiodidae), Decilaus nigronotatus, D. lateralis and D. striatus (all Curculionidae), were indicators of mature forest interior. \ \ A second survey compared beetles between logging regeneration, upslope mature forest interior, mature forest interior riparian areas, and streamside reserves that had been logged on both sides, in five stands of each of the four habitats. Streamside reserves (average width 40 +/-6 m (+/- 95% CI) from reserve edge to stream) supported different beetle assemblages to unlogged areas, and were probably entirely edge-effected. \ \ These results suggest that current corridor provisions, which rely heavily on riparian reserves, may be inadequate to conserve beetles dependent on mature forest interior. Reserve corridors may need to be wider, and should more often be positioned upslope away from riparian areas. Alternatively, a mix of different types of reservation strategies (e.g. conserving some contiguous blocks of mature forest in lieu of widened corridors) needs to be developed to increase the probability that edge-sensitive and mature forest specialist taxa will be conserved.

Spyridium microphyllum (F. Muell. ex Reissek) Druce and Spyridium obcordatum (Hook. f) W. M. Curtis are narrow endemic shrubs which are confined to Tasmania and are rare within their present ranges. Spyridium microphyllum is an obligate seed regenerator, whilst S. obcordatum is apparently able to regenerate both by seed and by resprouting. Ecological and biogeographical explanations for rarity in the two species were investigated by analysing their biological, bioclimatic, phytosociological and phytochorological correlates. Spyridium microphyllum was not significantly affected by grazing and is unlikely to be rare because of predation. Spyridium obcordatum is moderately to heavily grazed in summer but is able to recover biomass the following spring. Seedlings are likely to be particularly vulnerable. Seed production was not significantly affected at one site where the grazing trial was conducted, where rabbits were the main predator and the ground layer consisted of a high proportion of herbs and grasses. However, concentrations of native animals may significantly affect reproductive output where herbaceous food sources are scarce. Consequently, predation may contribute to rarity under these circumstances. Phenological observations revealed markedly different patterns relating to flowering, fruit maturation and time to reproductive maturity, suggesting that the two species may have different evolutionary histories. Spyridium microphyllum flowers in mid to late summer and seed is released one year later. This may enable plants to avoid competition for pollinators in spring, as well as maximise seed storage in the soil when ant activity is highest. Although seeds are exposed to threats for most of the year after fertilisation, the same pattern is known from widespread Spyridium taxa and does not explain rarity in S. microphyllum. However, plants may be disadvantaged by this regime where there is a reduced seed bank. Spyridium microphyllum does not set seed for at least four years after germination and may be eliminated by a series of successive fires. Spyridium obcordatum flowers in early spring and produces seed within two months. In this respect, it is similar to a number of widespread taxa within the Rhanmaceae and other families. Plants become reproductively active within two years. Thus, phenological patterns do not explain rarity in this species. Seed dormancy results from physical characteristics of the seed coat. Seed viability is high, and seed of both taxa germinate after scarification of the testa, or after stimulus by heat within similar ranges required to break dormancy in widespread congeners. In some instances, the two rare species responded to a wider range of heat stimuli than some widespread species. However, there were genecological differences in the germination behaviour of populations from different sites. In spite of these, rarity could not be explained by poor seed viability or lack of stimulus for germination. The loss of soil stored seed may partially contribute to rarity in the two species. Seed burial trials revealed S. microphyllum seed is only partially retained in the soil. Spyridium obcordatum was less vulnerable to seed bank depletion. However, losses are within the ranges recorded for other taxa and are replaced annually. Seed burial did not increase germinability in either of the two species. Consequently, loss of soil stored seed may be significant only if seed banks are not replenished annually because of repeated disturbance by fire or excessive predation. An analysis of the geographic patterns of distributions of Spyridium taxa determined that centres of endemism and species richness within the genus are in the South West Province of Western Australia and in southern South Australia. Eastern Tasmanian Spyridium species comprise an outlying concentration of endemics. There are no endemic centres in eastern Australia. The majority of taxa had no topographic or edaphic preference but were mainly associated with heathland or shrubland. A comparison of the geographic and climatic distributions of Spyridium taxa enabled hypotheses to be constructed which might explain rarity in the genus. Spyridium microphyllum and S. obcordatum were geographically and climatically narrowly distributed. In respect of the latter, they were similar to some geographically widespread Spyridium taxa and it was concluded that the two species are unlikely to be entirely restricted by climate. Recent divergence, inadequate time for dispersal, drastically reduced ranges or poor competitive ability were more likely explanations. Analysis of quadrat data using multivariate statistical methods showed that the two rare taxa are restricted by environmental conditions. Sites supporting the same species differ floristically and environmentally, and perturbations resulting from fire, soil disturbance or periodic flooding are influential events. Edaphic controls maintain environments where more competitive vegetation, especially trees and tall shrubs, are excluded. In combination, these characteristics ensure the perpetuation of shrub dominated vegetation supporting S. microphyllum or S. obcordatum. The frequency of such habitats in Tasmania and the range of habitats supporting populations, suggests that rarity in S. microphyllum and S. obcordatum cannot be attributed to confinement to a rare habitat. Thus, combinations of locally specific environmental conditions and interspecific competition, rather than a unique habitat, appears to be linked to rarity in both taxa. A phytochorological analysis determined that the two Spyridium species are associated with aggregates of taxa with restricted ranges. Spyridium microphyllum was primarily associated with other narrow endemics or with rare non - endemics concentrated in eastern Australia. Spyridium obcordatum had a stronger relationship with taxa concentrated in southern and southwestern Australia, some of which are rare in Tasmania. Where soil disturbance was substantial at one site, also thought to have been a refugium for forests during the late Pleistocene, S. obcordatum was associated with taxa widespread in southeastern and southern Australia. The results suggested that sources of interspecific competition have a basis in the disturbance and biogeographical histories of sites. Ultimate causes of rarity in S. microphyllum and S. obcordatum are best considered from a biogeographical viewpoint. Spyridium microphyllum is likely to be relictual under the present climate, having been a member of shrub dominated vegetation formerly more widespread in Tasmania under more arid conditions than exist at present. Spyridium obcordatum populations are likely to have been more or less continuous as part of a Bassian flora which is now extinct, the relicts of which have been incorporated into coastal heathland or open rocky environments. Thus, the most parsimonious explanation for rarity in both species is temporal remoteness from optimal conditions. Stochastic events relating to local extinction, establishment and maintenance of populations have influenced their survival. Ecological explanations for rarity in the two species are most likely to be a consequence of their present relictual status. These relate to poor competitive ability under conditions of improved soil moisture, or in closed or undisturbed vegetation, and a lack of safe sites for regeneration. Land use practices since European occupation of Tasmania further endanger populations at present.

The metabolic fate of two commonly occurring dietary terpenes in Australian marsupial eucalypt folivores has been studied. The detoxification mechanisms employed by these folivores were considered from an ecological perspective. Interactions between herbivores and their respective diets has received considerable attention over the last quarter of a century. A popular hypothesis by Freeland and Janzen (1974) states that feeding behaviour of herbivores is influenced by limitations of the body's mechanisms for detoxifying plant secondary metabolites (PSM). However, very little is understood about the physiological processes and limitations of detoxification in wild animals. This study provides an insight into these processes in marsupial eucalypt folivores from a range of feeding niches. An interspecies comparison was made of the metabolism of a bolus dose of the monoterpene p-cymene in a generalist herbivore, the brushtail possum (Trichosurus vulpecula), and three specialist folivores, the greater glider (Petauroides volans), the ringtail possum (Pseudocheirus peregrinus) and the koala (Phascolarctos cinereus), as well as in the laboratory rat (Rattus norvegicus) which provided a direct comparison to published data. Each animal was dosed, intragastrically, with single doses of p-cymene. Urine and faeces were collected pre- and post-dose. Chronic ingestion of 1,8-cineole, emulating its natural occurrence in the diet of brushtail possums and koalas, was also studied. Possums were fed an artificial diet in which 1,8-cineole concentrations were manipulated to cover a range of concentrations while koalas were fed Eucalyptus cephalocarpa, which has a terpene profile dominated by 1,8-cineole. Metabolites were identified by extraction, gas chromatography and mass spectrometry. Standards for many metabolites were isolated from urine to allow quantitation. A novel p-cymene metabolite, 2-p-carboxyphenylpropan-1,2-diol, was identified in the koala. Twelve.novel 1,8-cineole metabolites were identified from brushtail possum and koala urine. Eleven of these were isomers of hydroxy cineolic acid. The isomeric structure and partial stereochemistry for 7-hydroxy-9-cineolic acid were determined by NMR and mass spectrometry. Observational data from chronic ingestion of 1,8-cineole in possums demonstrated a threshold in maximum daily intake in most possums between 3 and 4 g/kg. The pattern of metabolites excreted in the brushtail possum during chronic ingestion demonstrated induction of enzymes responsible for producing the more oxidised metabolites during the first days of ingestion. There was no evidence of saturation of metabolic pathways associated with the larger intakes of 1,8-cineole. For both terpenes, species-specific patterns of metabolite excretion were evident and reflected the natural occurrence of eucalypt leaves in the different diets. The number and degree of oxidation of metabolites, as well as the role of conjugation, varied depending on the natural feeding behaviour of the animals. To facilitate studying the pattern of metabolism, terpene metabolites were grouped according to the total number of oxygen atoms (up to four) acquired during oxidation. Overall there was a progressive increase in the proportion of more extensively oxidised metabolites; from the rat, to the generalist and through to the specialist folivOres. The generalist utilised a multiplicity of non-specific oxidative pathways producing an array of metabolites covering all degrees of oxidation (9 metabolites of p-cymene and 18 metabolites of 1,8-cineole). On the other hand, the specialists had high capacity and specific oxidative pathways resulting in relatively few metabolites, all of which were radically oxidised. Glucuronidation was important in the generalists, compensating for their inability to excrete the same degree of radically oxidised metabolites as specialists. Approximately 40 - 50 % of p-cymene metabolites and up to 60 % of 1,8-cineole metabolites were conjugated with glucuronic acid in brushtail possums. No significant conjugation of metabolites was observed in the specialists. Increased polarity, whether achieved by glucuronidation or extensive oxidation, presumably results in the same overall enhanced capacity to excrete metabolites. It is proposed that, for specialists, oxidative efficiency reduces the necessity for subsequent conjugation, conserving glucuronic acid, a valuable resource in a nutritionally limited diet. The brushtail possum, however, consumes a varied and arguably better quality diet and can afford to excrete glucuronic acid in the detoxification of terpenes. Given that PSMs, such as terpenes, are always present in the eucalypt leaf diet of these folivores, these different strategies indicate that adaptation of detoxification mechanisms vary with dietary specialisation.

This thesis presents an historical background on bryological studies in Tasmania in order to provide a context for the floristic and ecological investigation of these cryptogams as a component of the epiphytic flora in rainforest corrununities. The period from the mid-nineteenth century to the early decades of the twentieth century saw the greatest effort in taxonomy of bryophytes. The discovery and description of much of the bryological flora of Tasmania resulted from the works of J.D. Hooker. R.A. Bastow, W.A. Weymouth and culminated in the two volume Bryophyta of Tasmania by Leonard Redway. There followed a period of almost half a century during which bryophytes received little attention and the last two decades have been devoted to a reappraisal of our taxonomic knowledge of this group. We can confidently recognise in our current flora 361 species of moss and 282 species of hepatics, and their biogeographical affinities to other southern land masses is discussed. In contrast there have been relatively few studies on other aspects of their biology and this thesis attempts to explore an ecological role of bryophytes. In this account a study on a particular ecological niche has been chosen. The floristic composition and adaptations of epiphytic bryophytes have been investigated on two major rainforest tree species in western and north-western Tasmania. Studies elsewhere on epiphytic bryophytes have produced varied results on both floristic composition and controlling factors. There was a total of 61 bryophytes recorded from the trunk region of Nothojagus cunninghamii (angiospenn) and Athrotaxis selaginoides (conifer) throughout 12 rainforest sites. Most species were facultative epiphytes. The hepatics were found to be the dominant component and the bark of N. cunninghamii was clearly the preferred substrate. There was considerable variation in numbers of epiphytes per tree and it would appear that microclimatic factors rather than bark characteristics are having the greater influence for a change in composition of the epiphytic flora from one forest system to another. The epiphytic bryophyte is almost entirely dependent on its surrounding environment for its existence. Therefore a variety of ectohydric strategies would appear to be employed to sustain the plant in that habitat. The majority of epiphytic mosses and hepatics studied on the two host tree species exhibit inter-organ capillary ec[ohydric conduction. A few displayed epi-organ capillary conduction (papillosity) and these adaptations were studied in detail using scanning microscopical techniques. The fonn of papillae ranged from a single dome-shaped papilla to multi-stalked papillae per cell. The advent of the environmental S.E.M. revealed a marked improvement in describing these varied delicale surface features when compared to the traditional S.E.M. procedure of fixation, dehydration and crilical point drying. The role of these papillae in distributing water over the surface of the plant as well as preventing excessive accumulation over the cell that would limit photosynthesis and respiration is discussed.

In order to understand the ecology of species, it is important to know how animals use their environment. This information can be determined at a range of spatial and temporal scales, and results may vary accordingly. The habitats that animals use determine resources available to them for different purposes (e.g. feeding and resting), and risks of predation to which they are exposed. Consequently, patterns of behaviour in relation to the environment are likely to influence survival and fitness. In Tasmania, Australia, three common and widely distributed native marsupial herbivores are the red-necked or Bennett's wallaby (Macropus rufogriseus rufogriseus), the red-bellied pademelon (Thylogale billardierii) and the common brushtail possum (Trichosurus vulpecula). Information on the behaviour of these species in relation to their environment is largely unavailable. This thesis describes the abundance, spatial organisation and habitat selection patterns of these three species, within a patchy forestry landscape. The five major habitat types within this environment were: (1) a prepared site that was planted with commercial Eucalyptus nitens seedlings during the study (referred to as 'young plantation'); (2) 5-7 year old E. nitens plantation; (3) grassland; (4) native forest; and (5) harvested uncleared land. Patterns of habitat use and selection were examined at three sequential spatio-temporal scales, within a hierarchy of decisions. These were: (1) location of home-range within the landscape, (2) feeding area within the home-range, and (3) vegetation consumed within one habitat, the young plantation. A radio-telemetry study of Bennett's wallabies, pademelons and possums was used to examine Scales 1 and 2 at the individual animal level. Animal surveys were carried out to examine Scale 2 for the entire herbivore community at the population level. These data were also used to estimate herbivore densities for the overall area and individual habitats. Fenced and unfenced vegetation plots, located within the young plantation, a highly used habitat, were monitored over time to examine Scale 3. As part of this research, modifications to common line-transect sampling methods were made. These enabled methods that are usually applied to daytime surveys in open habitat, to be used in nocturnal surveys in densely vegetated habitats. Accuracy testing of the radiotelemetry system is also described, as the patchiness of the landscape required careful interpretation of results. Results showed that, at night, wallabies and pademelons used all habitats, but consistently selected for open habitats (young plantation and grassland) across spatio-temporal scales. The use of these open habitats for feeding was confirmed by the large biomass of grass and forbs consumed by herbivores in a detailed study of vegetation on the young plantation. These patterns are consistent with their feeding strategies of grazer or mixed-feeder. During the day, the two macropod species avoided open habitats and showed strong selection for closed habitats. Wallabies selected for older plantation, while pademelons selected for native forest. This difference reflects their respective predator avoidance strategy (crypsis for pademelons) or escape response (flight for wallabies). Although shelter habitat was important to the two macropod species, their lack of selection at the home-range scale was suggested to reflect the fact that resting animals require little space. Patterns of habitat use and selection were difficult to interpret for possums, because results varied between the spatio-temporal scales. Spotlighting data showed that at night, possums selected for native forest, young plantation and particularly grassland at the population level. Radio-collared animals selected only for native forest. Older E. nitens plantations were avoided by possums at every level, and appeared to represent a biological desert to this species. High overall densities of wallabies and pademelons (0.3 and 1.5 animals.ha-1, respectively), and small, round, home-ranges (61.6 ha and 22.3 ha, respectively) suggested that these species benefited from the patchiness of this environment. This is attributed to the highly heterogeneous habitats, providing complimentary resources in the absence of ecotones or transitional flora zones, existing side by side, over a small spatial scale. In contrast, extremely low possum population density (0.04 animals.ha-1) and very large home-ranges (39.1 ha) suggested that resources, presumably den sites and/or food, were limited within this forestry environment. Results on the ecological aspects of the three herbivore species, described above, are put in the context of the Tasmanian forestry industry, particularly in relation to management of herbivore browsing damage to planted seedlings. Based on this work, I suggest that future management strategies could involve: (1) reducing fragmentation of the natural environment, which supports small home-ranges and high macropod densities, by designing larger, rounder plantations; (2) considering the placement of plantations in relation to the proximity of open (feeding grounds) and closed (shelter) habitats; (3) reducing or removing windrows from newly established plantations to restrict pademelons to the plantation edge; (4) deliberately retaining groundcover or using cover crops to provision herbivores with an alternative food source, as grasses and herbaceous dicots are eaten in preference to Eucalyptus nirens seedlings; (5) recognising that wallabies and pademelons remove a large biomass of groundcover and therefore, could play a positive role in weed control, reducing the need to herbicide plantations; (6) monitoring newly planted plantations at short and regular time intervals so that damage caused by insects versus mammals can be differentiated; and (7) avoiding planting in winter when macropods may have little alternative food to eat on newly established plantations.

Chameleon plant (Houttuynia cordata Thunb.) is native to Southern and Southeastern Asia. It can reproduce sexually through seeds and asexually through rhizomes and is invasive in multiple countries including the U.S. There has been much research on H. cordata as a medicinal species, and its potential as an invasive species is well documented. However, its herbicidal resistance has not previously been quantified. The objective of this study is to assess H. cordata’s resistance to herbicides. This study consisted of two rounds of tests to examine the resistance of H. cordata plants to three commonly used herbicides: SpeedZone, Weed-B-Gon, and Roundup. Two concentrations of each herbicide were used during each trial in the study: the recommended concentration and twice the recommended concentration. Herbicide treatments were applied outside the greenhouse. Herbicides were sprayed uniformly on the plants until the herbicide was dripping off the leaves. The growth of the treated plants was then monitored in the greenhouse. The herbicides generally reduced growth of the plants temporarily. However, plant extermination was not achieved. Plant samples from all herbicidal treatments regrew from rhizomes after all herbicide treatments. Results from the study showed that H. cordata could not be controlled by the recommended concentrations of herbicides commercially available for horticultural uses in the U.S. Doubling the recommended herbicide concentration was also ineffective in exterminating H. cordata plants. This research clearly showed that H. cordata has the potential to become a highly invasive species with the potential to negatively affect the ecological integrity of many communities in the U.S.

The principal focus of community ecology is to detect patterns in natural assemblages of plants and animals and explain the causal factors that underlie them. For the last 30 years, much of ecological theory has assumed that competition is the primary structuring force in communities. Competition is likely to be most important at the lower levels of community organisation, that of the guild. At the scale of large geographic regions, both evolutionary history and the physical environment are important in determining the composition of species assemblages. The structure of the guild of large dasyuroids or marsupial carnivores in Tasmania, Australia, is examined in relation to causal factors, especially the importance of competition. The relative significance of evolutionary history and the physical environment in shaping the composition of the Australian marsupial carnivore fauna is assessed. Evidence that competition was and still is an important structuring force in the guild is found. Evolutionary evidence is found in character displacement and morphological size patterning in canine strength, the trophic structure proximally related to feeding ecology of the large dasyuroids. The hypothesis of competition as the underlying causal factor is supported by similar patterning in prey size and a carnivore body size / prey size correlation. The existence of current competition in the guild can be inferred from the large extent of dietary overlap between species. The effects of competition are most evident between the two most similar species, the congeneric quolls. Resources are partitioned on at least three niche dimensions, diet, horizontal and vertical use of the habitat. Where dietary overlap is high between species, habitat use overlap is low, thereby reducing the potential for direct competition for individual prey items. Interference competition is most likely to occur over large carcasses. Mainly body size but also age of the carnivore determine interspecific dominance. Devils are usually dominant and are the primary scavengers, exhibiting adaptations for scavenging that are lacking in the other two species. Aspects of guild structure are influenced by several factors as follows. Size relationships in both body size and trophic stuctures are influenced by - latitudinal size correlations, competitive character displacement, size distributions of prey species which are shaped by the fractal dimensions of the habitat, and sexual selection. Locomotor morphology and habitat use of the carnivore species show evolutionary adaptations that match the arboreal or terrestrial habits of their particular size range of prey species. Competition may result in the depression of species populations. The rarity of spotted-tailed quolls can possibly be explained by higher dietary overlap and competition than is experienced by the other species. Numerical dominance of the guild by devils may relate in part to large body size and behavioural dominance in feeding situations. Substantial ecological convergence has occurred between the marsupial carnivore fauna of Australia and eutherian carnivore faunas on other continents. The main differences are the low diversity of species and eco-morphological types in Australia, which relate to poor soils and aridity. This supports the general view that the physical environment is more important than evolutionary history in shaping the composition of faunal assemblages.

No description available

Ground (soil) temperature data recorded by temperature data recorders buried in 1 cm and 10 cm depths of the ground surface at the mid-range of Yukidori Zawa during the JARE JARE-51 and 53 (2010–2012) are summarized in a table. Almost 2-year data of the ground temperature at two discrete depths were compiled in a text file from each recorder at the 1-hr intervalinterval. Using the present data with air temperature and solar radiation data from neighborhood automatic weather station reported previously, we have shown timing and period of soil thawing graphically.