Resource use by the Eastern Grey Kangaroo and the Black Wallaby in a managed remnant woodland community

This work studies the interactions and relationships that exist between Eastern Grey Kangaroos and Black Wallabies in their utilisation of spatial and trophic resources in a managed remnant woodland community. The thesis provides a closer understanding of the way in which these species impact upon their habitats. The Coranderrk Reserve, near Healesville in eastern Victoria, Australia was the study site. A floristic analysis of the communities of the study site was conducted. This consisted of plant biomass measurements, estimates of plant abundance and cover determination. Faecal pellets from Eastern Grey Kangaroos and Black Wallabies were collected from ten vegetation communities during three different plant productivity periods. The spatial and temporal distribution of the animals was identified by analysing the frequency of occurrence of faecal pellets in the various communities. The use of faecal pellet density as a measure of habitat utilisation was examined. Eastern Grey Kangaroos utilised communities which were characterised by the presence of a dense grassy statum. Black Wallabies were able to utilise all of the communities of the study site regardless of their floristic composition. A reference herbarium of the leaf epidermis of 233 possible forage plant species was accumulated. These epidermal specimens were prepared for Confocal Scanning Laser Microscopy. The information gained was enhanced and stored digitally. Diagnostic information critical for the identification of plant epidermal fragments was assembled into a computer database. This was used to assist in the recognition of unknown epidermal fragments in macropodid faeces. These epidermal plant recognition techniques enabled a list of the contents of Eastern Grey Kangaroo and Black Wallaby faeces during the sampling periods in the individual communities, to be accumulated. Eastern Grey Kangaroos utilised forage which consisted largely of grass and their diets were similar regardless of their feeding sites or the time of the year. Black Wallaby diets were heterogenous with wide variations over space and time observed. The implications of these findings for current wildlife management practices were considered. Black Wallaby and Eastern Grey Kangaroo herbivory have significant impacts on ecosystem integrity. Management strategies should seek to establish ecologically sustainable populations of both species in remnant woodlands where conservation values are important.

The impact of grazing by eastern grey kangaroos (macropus giganteus) on vegetation recovery after fire at Reef Hills regional park, Victoria

In southeastern Australia ecological burning is frequently used to maintain a number of plant and animal populations. However, many of these prescribed fires are small, and may focus intense grazing activity on new regrowth. At Reef Hills Regional Park, Victoria shrub species have senesced, presumably due to the absence of fire. Ecological burning may be necessary to promote regeneration, however, the population density of the Eastern Grey Kangaroo (Macropus giganteus) is high (approx 38 per km2), and grazing pressure presents a significant risk to postfire vegetation recovery. An assessment of grazing patterns and their effects on postfire recovery was carried out at Reef Hills Regional Park through grazing exclusion plots. Preferential grazing by Eastern Grey Kangaroos occurred on small burnt plots compared to adjacent unburnt areas as determined by faecal pellet counts. On burnt areas, there was a significant reduction in shrub diversity on grazed plots compared to ungrazed plots. Most observations of kangaroos were of animals grazing on farmland surrounding the Park, and it is likely that any burning might shift grazing from farmland to burnt areas when new growth occurs. This needs to be considered before any ecological burn plan is applied to manage vegetation communities, particularly if the plan requires small areas to be burnt. We recommended that a large area up to 200 ha area be burnt and monitored to determine whether burning larger areas disperses grazing pressure from macropods to a level where impacts on vegetation are reduced and localized plant extinctions do not occur.

The Viggers & Hearn conundrum : a kangaroo home range study with no implications for land management

1.
Viggers & Hearn (2005) examined the encroachment of native herbivores on to farmland.
They presented kangaroo home range estimates and pasture biomass data for
three sites in south-eastern Australia, then made broad management recommendations
regarding the preservation of remnant habitat.
2.
While Viggers & Hearn identified potentially important patterns, we believe that
their data were neither sufficient nor appropriate to reveal the processes that underlie
these patterns.
3.
Specifically, their study was unreplicated at the land-use level, used inappropriate
density estimates for their study populations, failed to measure resources adequately,
used flawed methods of home range analysis, and demonstrated limited understanding
of key concepts and of their study species and thus could not draw valid conclusions.
4.
Synthesis and applications.
In view of these fundamental problems, we recommend
that decisions on the management of kangaroos

Large-herbivore distribution and abundance : intra-and interspecific niche variation in the tropics

Determining the biological and environmental factors that limit the distribution and abundance of organisms is central to our understanding of the niche concept and crucial for predicting how species may respond to large-scale environmental change, such as global warming. However, detailed ecological information for the majority of species has been collected only at a local scale, and insufficient consideration has been given to geographical variation in intraspecific niche requirements. To evaluate the influence of environmental and biological factors on patterns of species distribution and abundance, we conducted a detailed, broadscale study across the tropical savannas of northern Australia on the ecology of three large, sympatric marsupial herbivores (family Macropodidae): the antilopine wallaroo (Macropus antilopinus), common wallaroo (M. robustus), and eastern grey kangaroo (M. giganteus). Using information on species abundance, climate, fire history, habitat, and resource availability, we constructed species' habitat models varying from the level of the complete distribution to smaller regional areas. Multiple factors affected macropod abundance, and the importance of these factors was dependent on the spatial scale of analyses. Fire regimes, water availability, geology, and soil type and climate were most important at the large scale, whereas aspects of habitat structure and interspecific species abundance were important at smaller scales. The distribution and abundance of eastern grey kangaroos and common wallaroos were strongly influenced by climate. Our results suggest that interspecific competition between antilopine wallaroos and eastern grey kangaroos may occur. The antilopine wallaroo and eastern grey kangaroo (grazers) preferred more nutrient-rich soils than the common wallaroo (grazer/browser), which we relate to differences in feeding modes. The abundance of antilopine wallaroos was higher on sites that were burned, whereas the abundance of common wallaroos was higher on unburned sites. Future climate change predicted for Australia has the capacity to seriously affect the abundance and conservation of macropod species in tropical savannas. The results of our models suggest that, in particular, the effects of changing climatic conditions on fire regimes, habitat structure, and water availability may lead to species declines and marked changes in macropod communities.

Separating the influences of environment and species interactions on patterns of distribution and abundance : competition between large herbivores

* 1
Much recent research has focused on the use of species distribution models to explore the influence(s) of environment (predominantly climate) on species’ distributions. A weakness of this approach is that it typically does not consider effects of biotic interactions, including competition, on species’ distributions.
* 2
Here we identify and quantify the contribution of environmental factors relative to biotic factors (interspecific competition) to the distribution and abundance of three large, wide-ranging herbivores, the antilopine wallaroo (Macropus antilopinus), common wallaroo (Macropus robustus) and eastern grey kangaroo (Macropus giganteus), across an extensive zone of sympatry in tropical northern Australia.
* 3
To assess the importance of competition relative to habitat features, we constructed models of abundance for each species incorporating habitat only and habitat + the abundance of the other species, and compared their respective likelihoods using Akaike's information criterion. We further assessed the importance of variables predicting abundance across models for each species.
* 4
The best-supported models of antilopine wallaroo and eastern grey kangaroo abundance included both habitat and the abundance of the other species, providing evidence of interspecific competition. Contrastingly, models of common wallaroo abundance were largely influenced by climate and not the abundance of other species. The abundance of antilopine wallaroos was most influenced by water availability, eastern grey kangaroo abundance and the frequency of late season fires. The abundance of eastern grey kangaroos was most influenced by aspects of climate, antilopine wallaroo abundance and a measure of cattle abundance.
* 5
Our study demonstrates that where census and habitat data are available, it is possible to reveal species’ interactions (and measure their relative strength and direction) between large, mobile and/or widely-distributed species for which competition is difficult to demonstrate experimentally. This allows discrimination of the influences of environmental factors and species interactions on species’ distributions, and should therefore improve the predictive power of species distribution models.

Contribution of multi-tenure reserve networks to biodiversity conservation

A consistent and integrated approach to nature conservation across the landscape and regardless of tenure is widely recognised as essential in ensuring the effective conservation of biodiversity. 'Multi-tenure reserve networks', which incorporate public and private lands managed for conservation, are considered a means of achieving landscape scale conservation. Biosphere Reserves (BR) and Conservation Management Networks (CMN) are characteristic models in Australia. This thesis aims to evaluate the role of such networks in protecting biodiversity, specifically by: (1) analysing the spatial configuration (size, shape, connectivity) of networks and their individual components; (2) evaluating the contribution of networks (in real terms and in reporting procedures) to biodiversity conservation objectives; (3) analysing the influence of the attitudes and perceptions of land managers on the functionality of networks; and (4) evaluating the influence of coordinating bodies on network functionality. In order to account for deficiencies in existing classifications of conservation lands, a new classification system was developed for this thesis - the Conservation Lands Classification. This classification incorporates conservation mechanisms on public and private lands and forms the basis for comparing network components in three Australian case studies - the Bookmark BR located in the Murray Mallee of South Australia, the Gippsland Plains CMN on the eastern Gippsland Plains of Victoria and the Grassy Box Woodlands CMN across the inland slopes of New South Wales. The spatial configuration of individual components within networks was measured using spatial analysis techniques within a geographic information system (GIS). GIS was also used to measure the contribution that networks made to a comprehensive, adequate and representative reserve system through the ecosystems they protected. The attitudes and perceptions of landowners and managers within the networks were obtained using questionnaires. Questionnaires were also sent to network coordinators. Statistical and descriptive analysis was conducted on the results. The sizes of individual components varied markedly between the three networks, however within each network public reserves were on average larger than private conservation lands. Although levels of physical connectivity varied between networks, Bookmark BR and Gippsland Plains CMN showed greater similarity to each other than to the Grassy Box Woodlands CMN. The findings raise important questions about the real and perceived differences in the BR and CMN models. All networks, and particularly those components outside the public protected area estate, contributed to enhancing the protection of ecosystems unrepresented or under-represented in the reserve system, although the extent of this contribution varied between networks. Trade-offs between reserve design efficiency and a contribution to a comprehensive, adequate and representative reserve system were evident between networks. Bookmark BR was characterised by high connectivity, strong reserve design integrity but a lower contribution to protecting under-reserved ecosystems, whereas the opposite was evident in the Grassy Box Woodlands CMN. Over 88% of managers considered their involvement in multi-tenure reserve networks to be a positive or very positive experience. A lack of resources and time for management were considered major limitations of these networks. The majority (80%) of private land managers within networks were willing to be included in a national reserve system of conservation lands. This has important implications for the Australian National Reserve System, which currently incorporates mostly public land. The changing nature of the network coordination arrangements suggests an organic fluid evolution of network structures is likely, contrasting with the desire for legalistic and administrative rigidity promoted by government agencies. The thesis concludes that all the networks studied contribute in varying degrees to biodiversity conservation. The key factors influencing the current and potential contribution that such networks make are: (1) the aims, directions and restrictions set by or imposed upon the coordinating body; and (2) the biophysical nature of the surrounding bioregion and resultant historical land use and tenure pattern. Although the successful operation of such 'multi-tenure' networks ultimately relies on the willing participation of private landholders, ongoing institutional support is likely to be required for maintaining networks in the longer term. Considering networks are increasingly formed outside of the influence of government institutions, this presents a significant challenge for effective coordinated conservation.

Diet and habitat of the powerful owl (Ninox strenua) living near Melbourne

The diet of Powerful Owls (Ninox strenua) living at Christmas Hills, 35km north-east of Melbourne was examined by analysis of 686 regurgitated pellets collected over two years. An aid was also developed to help identify potential mammalian prey species based on hair and skeletal characteristics. The following features were found to be most useful in distinguishing between the three species of arboreal marsupials - Common Ringtail Possum (Pseudocheirus peregrinus), Common Brushtail Possum (Trichosurus vulpecula) and Sugar Glider (Petaurus breviceps): - Cross-sectional width of primary guard hairs. - The size and shape of the nasal, frontal, parietal and squamosal bones of the skull. - Dentition. The size and shape of the upper incisor, canine and premolar teeth. The size and shape of the lower incisor and premolar teeth. - The size of the humerus. The Sugar Glider has a much smaller humerus than that of the Common Ringtail Possum and the Common Brushtail Possum. In the Common Brushtail Possum the entepicondyle ends in a very sharp point but the Common Ringtail Possum this point is not as sharp. - The Common Ringtail Possum’s femur has a very prominent trochanter which projects further than that in the Common Brushtail Possum. The femur of the Sugar Glider is distinguished by having a very large depression between the condyle and the trochanter. - The Common Brushtail Possum’s scapula has a narrower lower blade (relative to length) than that in the Common Ringtail Possum. The scapula of the Sugar Glider is smaller in size than that of the other two possums.The pelvic girdle Of the Common Brushtail Possum has a much wider ischium than those of the Common Brushtail Possum and the Sugar Glider. The ilium of the Sugar is much narrower and smaller than that of the other two possums Mammalian prey was found in 89%, insects in 13% and birds in 10% of the pellets. Of the mammals, Common Ringtail Possums occurred most frequently in the pellets over the year. There was no seasonal difference in the frequency of occurrence of Common Ringtail Possums and Sugar Gliders in pellets. However, Common Brushtail Possums were more likely to be taken in spring than in the other seasons. More adult Common Ringtail Possums were taken as prey than were other age classes over the year, except in summer when high numbers of young were consumed by the owls. The habitat of the Powerful Owl was examined by ground surveys and spotlight surveys in sixteen sites within the Warrandyte-Kinglake Nature Conservation Link. Four categories of survey sites were chosen with the following features. Category A - Sites with a dense understorey of shrubs and small trees, as well as many old trees (>10/ha) which might be suitable for nest hollows. Category B - Sites which lacked a dense understorey of shrubs and small trees and containing few or no old trees suitable for nest hollows. Category C - Sites with a dense understorey of shrubs and small trees but containing few or no old trees suitable for nest hollows. Category D - Sites which lacked a dense understorey of shrubs and small trees but having old trees (>10/ha) which might be suitable for nest hollows. High prey densities strongly correlated with the presence of hollows at these sites. In the light of the results, management recommendations were made for the future conservation of the Powerful Owls living at Christmas Hills. The following recommendations were particularly important: 1. Cleared or semi - cleared land within the Warrandyte Kinglake Nature Conservation Link be revegetated using indigenous species of eucalypts and waffles in order to provide a contiguous native forest corridor for the movement of possums and gliders between the Yarra River Valley and the Kinglake Plateau. 2. Continued planting of Eucalyptus spp. and Acacia spp. in the forested areas of the Warrandyte-Kinglake Nature Conservation Link. 3. Continued protection of healthy living trees to provide a continuous supply of hollow trees. 4. No falling of dead standing trees for firewood collecting as these can provide nest hollows for prey species of the Powerful Owl.

Resource partitioning in sympatric populations of Red-necked Wallabies and Black Wallabies

Examines the potential for competition to occur between the Red-necked Wallaby and the Black Wallaby by examining the extent of overlap in their dietary preferences and in their utilisation of habitat at different times of the day and year. Significant separation occured between species to facilitate coexistence.

Acculturation and its effects on the nutrition and physical activity of African migrant children

Studies the nutritional status, food intake, physical activity and acculturation in African migrant children living in Melbourne. Higher than expected overweight/obesity prevalence, and malnutrition, especially wasting, was observed in the study population. These children had high energy and macronutrient intake; compensated by high physical activity level. There was a strong positive association between acculturation and obesity.

An integrated workplace mental health intervention in a policing context: protocol for a cluster randomised control trial

BACKGROUND: In this paper, we present the protocol for a cluster-randomised trial to evaluate the implementation and effectiveness of a workplace mental health intervention in the state-wide police department of the south-eastern Australian state of Victoria. n. The primary aims of the intervention are to improve psychosocial working conditions and mental health literacy, and secondarily to improve mental health and organisational outcomes.

METHODS/DESIGN: The intervention was designed collaboratively with Victoria Police based on a mixed methods pilot study, and combines multi-session leadership coaching for the senior officers within stations (e.g., Sergeants, Senior Sergeants) with tailored mental health literacy training for lower and upper ranks. Intervention effectiveness will be evaluated using a two-arm cluster-randomised trial design, with 12 police stations randomly assigned to the intervention and 12 to the non-intervention/usual care control condition. Data will be collected from all police members in each station (estimated at >20 per station). Psychosocial working conditions (e.g., supervisory support, job control, job demands), mental health literacy (e.g., knowledge, confidence in assisting someone who may have a mental health problem), and mental health will be assessed using validated measures. Organisational outcomes will include organisational depression disclosure norms, organisational cynicism, and station-level sickness absence rates. The trial will be conducted following CONSORT guidelines. Identifying data will not be collected in order to protect participant privacy and to optimise participation, hence changes in primary and secondary outcomes will be assessed using a two-sample t-test comparing summary measures by arm, with weighting by cluster size.

DISCUSSION: This intervention is novel in its integration of stressor-reduction and mental health literacy-enhancing strategies. Effectiveness will be rigorously evaluated, and if positive results are observed, the intervention will be adapted across Victoria Police (total employees ~16,500) as well as possibly in other policing contexts, both nationally and internationally.

What determines habitat quality for a declining woodland bird in a fragmented environment: the grey-crowned babbler pomatostomus temporalis in South-Eastern Australia?

Understanding what constitutes high quality habitat is crucial for the conservation of species, especially those threatened with extinction. Habitat quality frequently is inferred by comparing the attributes of sites where a species is present with those where it is absent. However, species presence may not always indicate high quality habitat. Demographic parameters are likely to provide a more biologically relevant measure of quality, including a species' ability to successfully reproduce. We examined factors believed to influence territory quality for the grey-crowned babbler (Pomatostomus temporalis), a cooperatively breeding woodland bird that has experienced major range contraction and population decline in south-eastern Australia. Across three broad regions, we identified active territories and determined the presence of fledglings and the size of family groups, as surrogates of territory quality. These measures were modelled in relation to habitat attributes within territories, the extent of surrounding wooded vegetation, isolation from neighbouring groups, and the size of the neighbourhood population. Fledgling presence was strongly positively associated with group size, indicating that helpers enhance breeding success. Surprisingly, no other territory or landscape-scale variables predicted territory quality, as inferred from either breeding success or group size. Relationships between group size and environmental variables may be obscured by longer-term dynamics in group size. Variation in biotic interactions, notably competition from the noisy miner (Manorina melanocephala), also may contribute. Conservation actions that enhance the number and size of family groups will contribute towards reversing declines of this species. Despite associated challenges, demographic studies have potential to identify mechanistic processes that underpin population performance; critical knowledge for effective conservation management.

Interspecific and geographic variation in the diets of sympatric carnivores: dingoes/wild dogs and red foxes in south-eastern Australia

Dingoes/wild dogs (Canis dingo/familiaris) and red foxes (Vulpes vulpes) are widespread carnivores in southern Australia and are controlled to reduce predation on domestic livestock and native fauna. We used the occurrence of food items in 5875 dingo/wild dog scats and 11,569 fox scats to evaluate interspecific and geographic differences in the diets of these species within nine regions of Victoria, south-eastern Australia. The nine regions encompass a wide variety of ecosystems. Diet overlap between dingoes/wild dogs and foxes varied among regions, from low to near complete overlap. The diet of foxes was broader than dingoes/wild dogs in all but three regions, with the former usually containing more insects, reptiles and plant material. By contrast, dingoes/wild dogs more regularly consumed larger mammals, supporting the hypothesis that niche partitioning occurs on the basis of mammalian prey size. The key mammalian food items for dingoes/wild dogs across all regions were black wallaby (Wallabia bicolor), brushtail possum species (Trichosurus spp.), common wombat (Vombatus ursinus), sambar deer (Rusa unicolor), cattle (Bos taurus) and European rabbit (Oryctolagus cuniculus). The key mammalian food items for foxes across all regions were European rabbit, sheep (Ovis aries) and house mouse (Mus musculus). Foxes consumed 6.1 times the number of individuals of threatened Critical Weight Range native mammal species than did dingoes/wild dogs. The occurrence of intraguild predation was asymmetrical; dingoes/wild dogs consumed greater biomass of the smaller fox. The substantial geographic variation in diet indicates that dingoes/wild dogs and foxes alter their diet in accordance with changing food availability. We provide checklists of taxa recorded in the diets of dingoes/wild dogs and foxes as a resource for managers and researchers wishing to understand the potential impacts of policy and management decisions on dingoes/wild dogs, foxes and the food resources they interact with.

Effects of fragmented habitat and fire on the distribution and ecology of the swamp antechinus (Antechinus minimus maritimus) in the Eastern Otways, Victoria

This study investigated the distribution, habitat and population dynamics of the swamp antechinus (Antechinus minimus maritimus) in the eastern Otway Ranges. The species has a restricted, disjunct distribution and has been recorded at 25 sites between 1969 and 1999. All sites were located within 7 km of the coast, occurred at altitudes up to 80 m above sea level and within 10 m of a gully. Analysis of landscape site variables identified sun index as being significant in determination of the probability of occurrence of A. minimus. The presence of A. minimus is negatively associated with sun index, occuring at sites that have a southerly aspect and gentle slope. A. minimus was located in a range of structural vegetation including Open Forest, Low Woodland, Shrubland and Hummock Grassland and a number of floristic groups, some characterised by high frequencies of sclerophyll shrubs, others by high frequencies of Pteridium esculentum, hummock grasses and herbaceous species. A. minimus occurs in fragmented, small populations with maximum population densities of 1.1–18 ha^–1. Populations at inland sites became extinct after the 1983 wildfire which burnt 41 000 ha. These sites have not been recolonised since, while on the coast the species did not re-establish until 1993–97. One population that is restricted to a narrow coastal strip of habitat is characterised by high levels of transient animals. The species is subject to extinction in the region due to habitat fragmentation, coastal developments and fire. Management actions to secure the present populations and ensure long-term survival of the species in the area are required and include implementation of appropriate fire regimes, prevention of habitat fragmentation, revegetation of habitat, and establishment of corridor habitat.

Black and white is always grey-the power of the police to conduct a strip search in Victoria

The performance of a strip search by a police officer is a serious interference with the liberty and dignity of an individual. However, it is considered by police to be an important part of their law enforcement armory and one that is increasingly necessary to utilise to assist in the investigation and prosecution of drug-related crimes. This article considers the troublesome issue of whether and in what circumstances the common law may extend to police the power to conduct a strip search. In addition, there is an examination of the statutes and regulations that purportedly give police in Victoria the power to strip search with particular attention given to ss 81 and 82 of the Drugs, Poisons and Controlled Substances Act 1981 (Vic).

Floristic and structural characteristics of a coastal heathland exhibiting symptoms of Phytophthora cinnamomi infestation in the eastern Otway Ranges, Victoria

The floristics and structure of heathland vegetation exhibiting symptoms of Phytophthora cinnamomi Rands infestation was assessed at two sites in heathlands at Anglesea, Victoria. There were significant effects in both floristics and structure. Thirteen heathland species were significantly less abundant in diseased areas and 23 species were more abundant. Diseased (infested) vegetation, when compared with non-diseased areas, had less cover of Xanthorrhoea australis and shrub species and a greater cover of sedges, grasses and open ground. Structural differences were observed between heights 0 and 0.6 m, with a decline in cover recorded in diseased vegetation. Non-metric multidimensional scaling ordination of the floristic data showed a clear separation of diseased and non-diseased vegetation and that changes in floristic composition post-infestation were similar at both sites. Although there was some evidence of regeneration of X. australis, the recovery capacity of other susceptible species at Anglesea is unknown. The long-term consequences of loss of species and structure in the eastern Otways mean that the vegetation is unlikely to return to former status, especially if the pathogen continues to reinfect.