Ecology of Pittosporum undulatum Vent. (Pittosporaceae) an environmental weed in south east Australia

Pittosporum undulatum Vent. (Sweet Pittosporum) is a densely foliaged tall shrub or small tree, native to the wet forests of south east Australia, This species now functions as a serious environmental weed in a range of habitats in Australia and on other continents and islands throughout the temperate, sub-tropical and tropical zones. This study investigated some of the ecological causes and consequences of P. undulatum invasion across a range of habitat types in south east Australia. Key aspects of P. undulatum biology and ecology investigated in the current study include; patterns of morphological variation across the range of habitats occupied (as a measure of the species’ plasticity), dispersal ecology and seed germinability, population structure and spatial pattern, community relationships and the ecological impacts of invasion. Phenotypic plasticity is considerable in P. undulatum. No clear patterns of geographic variation emerged from a study of leaf morphological attributes across the current range of this species on mainland south east Australia. The pattern of morphological variation is particularly complex in Victoria, where the invasion of this species is most advanced. The species’ adaptability to a range of environments and environmental conditions will likely promote further range expansion. The abundant winter fruit crop produced by functionally female P. undulatum plants attracts a suite of generalist opportunistic frugivores, which feed on P. undulatum fruits and seeds at various stages of fruit dehiscence, thereby enhancing dispersal opportunities for this species. P. undulatum seed collected from natural and invasive populations, at two stages of fruit maturity and from the scats and pellets of dispersal agents, displayed high germinability. European Blackbirds and Pied Currawongs are implicated as the main avian dispersal agents of P undulatum in south east Australia. The broader ecological implications of developing relationships between invasive fleshy-fruited bird-dispersed plant species and adaptive frugivores are likely to be considerable. The distribution of P. undulatutn seedlings was significantly negatively correlated with adult conspecifics and significantly positively correlated with trees and shrubs of other genera. This pattern reflects the importance of both firugivorous dispersal agents and the species’ germination and establishment requirements, in shaping the contagious distribution pattern typical of this species. These analyses suggest that recruitment opportunities for conspecific seedlings are limited beneath the canopy of adult conspecifics. Densities of P. undulatum were on average, 2.7 times higher in invaded populations, compared to the natural populations sampled. A male-bias was evident in all populations and no relationships between reproductive activity and the density of seedlings and juveniles were evident. Invading populations of P. undulatum impose substantial changes on ecosystem-level properties and functions. Mean species richness and cover-abundance declined notably once P. undulatum cover-abundance exceeded 20% at the invaded sites and 60% at the natural sites sampled. The natural communities sampled displayed comparatively greater resilience to the competitive effects of P. undulatum, but community attributes were affected at high densities and cover-abundance of this species. The cover-abundance of herbs and grasses declined most substantially with increasing P. undulatum at invaded sites, whereas, at the natural sites sampled, the species’ structural analogues appeared to be most affected by increasing P. undulatum cover-abundance. This study has demonstrated that the ecological consequences of P. undulatum population expansion are substantial and contribute to changes in the composition and successional trajectory of affected communities. These processes ultimately lead to the loss and simplification of biodiversity values and the homogenisation of affected habitats. P. undulatum has the potential to emerge as one of south east Australia's most serious environmental weed species.

Public and stakeholder values and knowledge of wildlife in Victoria, Australia

Prompted by a lack of human dimensions research in Australia, this study investigated the values and knowledge relating to wildlife held by members of the public within distinct demographic subsets of the Victorian population and members of wildlife management stakeholder groups; and compared these characteristics with how Victorian wildlife managers perceive these groups. A combination of semi-structured interviews and postal questionnaires were used. Fifteen in-depth interviews were conducted to explore how wildlife managers perceive the values and knowledge of wildlife held by members of various subsets of the Victorian population. A total of 1,431 questionnaires were completed by members of 13 public and stakeholder groups throughout Victoria, and these were analysed to explore values and knowledge relating to wildlife in Victoria. The findings of this study suggest that Victorian people have a strong emotional attachment to individual animals (the humanistic value), and an interest in learning about wildlife (the curiosity/learning/interacting value). The dominionistic/wildlife-consumption, utilitarian-habitat, aesthetic and negativistic values were not expressed by the majority of respondents from the public samples. The data also suggest that Victorian people have relatively low levels of factual knowledge about Australian wildlife. Thus, wildlife managers should expect support for wildlife management objectives that reflect the strong humanistic orientation of Victorians and tailor management and education programs to appeal to this value and Victorians' interest in learning about wildlife. Members of the Field Naturalists Club of Victoria (FNCV), Bird Observers Club of Australia (BOCA), Australian Conservation Foundation (ACF) stakeholder groups and management agency Parks Victoria expressed a strong interest in learning about wildlife. Members of the Royal Society for the Prevention of Cruelty to Animals (RSPCA) obtained high humanistic value scores; and members of the Victorian Field and Game Association (VFGA) obtained high domimomstic/wildlife-consumption value scores. Importantly, the humanistic and curiosity/learning/interacting values were the most strongly expressed values in all six groups and these values could be the key to more effective communication and collaboration between groups. Relationships between demographic factors, and values and knowledge relating to wildlife were found. For example, rural Victorians held a stronger dominionistic/ wildlife-consumption value than urban Victorians; females held stronger humanistic, curiosity/learning/interacting and negativistic values than males; young Victorians (18-34 years) held a lower curiosity/learning/interacting value and lower factual knowledge of wildlife than older Victorians; and more highly educated Victorians were more knowledgeable about wildlife than people with less formal education. No statistically significant differences were found between the values and knowledge of wildlife held by different income classes. While relationships between demographic factors, and values and knowledge relating to wildlife were found, they were generally much smaller than expected based on wildlife managers' perceptions and previous research. For example, the results suggest that Victorian females have a slightly stronger humanistic value of wildlife than males do. However, the important message emerging from the data is that males and females both express a strong emotional attachment to individual animals. Importantly, the results indicate that the effects of demographic factors on values and knowledge relating to wildlife are not always consistent across different geographic locations and stakeholder groups. For example, the slightly stronger interest in learning about wildlife among females when compared with males was observed in the rural and urban-fringe samples but not in the urban samples. This suggests that caution must be used when generalising the findings from human dimensions studies from one type of community or stakeholder group to another. Management programs should be tailored to the specific characteristics of the target audience. The findings also indicate that Victorian wildlife managers have diverse perceptions about the values and knowledge of wildlife held by members of different publics and stakeholder groups, and that the perceptions held by wildlife managers are not always consistent with the actual values and knowledge of wildlife held by members of different publics and stakeholders. For example, counter to the perceptions expressed by the interviewed wildlife managers, the interest in and factual knowledge of wildlife held by members of voluntary conservation groups equalled or surpassed that of wildlife managers; young Victorian adults (18-34 years) held a slightly lower curiosity/learning/interacting value and slightly lower level of factual knowledge of wildlife than older Victorians; and rural and urban communities in Victoria held low dominionistic and utilitarian values. Such discrepancies highlight the importance of investigating the actual values and knowledge held by members of such groups, so that appropriate and effective wildlife management programs can be implemented. Inaccurate perceptions and assumptions may contribute to ineffective communication between managers, stakeholders and publics; and adversely effect the success of wildlife management programs.

Ecology of arboreal marsupials in a network of remnant linear habitats

Linear strips of vegetation set within a less-hospitable matrix are common features of landscapes throughout the world. Depending on location, form and function, these linear landscape elements include hedgerows, fencerows, shelterbelts, roadside or streamside strips and wildlife corridors. In many anthropogenically-modified landscapes, linear strips are important components for conservation because they provide a large proportion of the remaining wooded or shrubby habitat for fauna. They may also function to provide connectivity across the landscape. In some districts, the linear strips form an interconnected network of habitat. The spatial configuration of remnant habitat (size, shape and arrangement) may influence habitat suitability, and hence survival, of many species of plant and animal in modified landscapes. Near Euroa in south-eastern Australia, the clearing and fragmentation of temperate woodlands for agriculture has been extensive and, at present, less than 5% tree cover remains, most of which (83%) occurs as linear strips along roads and streams. The remainder of the woodland occurs as relatively small patches and single isolated trees scattered across the landscape. As an assemblage, arboreal marsupials are woodland dependent and vary in their sensitivity to habitat loss and fragmentation. This thesis focusses on determining the conservation status of arboreal marsupials in the linear network and understanding how they utilise the landscape mosaic. Specifically, the topics examined in this thesis are: (1) the composition of the arboreal marsupial assemblage in linear and non-linear woodland remnants; (2) the status and habitat preferences of species of arboreal marsupial within linear remnants; and (3) the ecology of a population of the Squirrel Glider Petaurus norfolcensis in the linear network, focusing on population dynamics, spatial organisation, and use of den trees. The arboreal marsupial fauna in the linear network was diverse, and comprised seven out of eight species known to occur in the district. The species detected within the strips were P. norfolcensis, the Sugar Glider Petaurus breviceps, Common Brushtail Possum Trichosums vulpecula, Common Ringtail Possum Pseudocheirus peregrinus, Brush-tailed Phascogale Phascogale tapoatafa, Koala Phascolarctos cinereus and Yellow-footed Antechinus Antechinus flavipes. The species not detected was the Feathertail Glider Acrabates pygmaeus. Survey sites in linear remnants (strips of woodland along roads and streams) supported a similar richness and density of arboreal mammals to sites in non-linear remnants (large patches or continuous tracts of woodland nearby). Furthermore, the combined abundance of all species of arboreal marsupials was significantly greater in sites in the linear remnants than in the non-linear remnants. This initial phase of the study provided no evidence that linear woodland remnants support a degraded or impoverished arboreal marsupial fauna in comparison with the nonlinear remnants surveyed. Intensive trapping of arboreal marsupials within a 15 km linear network between February 1997 and June 1998 showed that all species of arboreal marsupial (except A. pygmaeus) were present within the linear strips. Further analyses related trap-based abundance estimates to measures of habitat quality and landscape structure. Width of the linear habitat was significantly positively correlated with the combined abundance of all arboreal marsupials, as well as with the abundance of P. norfolcensis and T. vulpecula. The abundance of T. vulpecula was also significantly positively correlated with variation in overstorey species composition, Acacia density and the number of hollow-bearing trees. The abundance of P. norfolcensis was positively correlated with Acacia density and canopy width, and negatively correlated with distance to the nearest intersection with another linear remnant. No significant variables were identified to explain the abundance of P. tapoatafa, and there were insufficient captures of the remaining species to investigate habitat preferences. Petaurus norfolcensis were resident within the linear network and their density (0.95 -1.54 ha-1) was equal to the maximum densities recorded for this species in continuous forest elsewhere in south-eastern Australia. Rates of reproduction were also similar to those in continuous forest, with births occurring between May and December, a mean natality rate of 1.9, and a mean litter size of 1.7. Sex ratios never differed significantly from parity. Overall, the population dynamics of P. norfolcensis were comparable with published results for the species in contiguous forest, clearly suggesting that the linear remnants currently support a self-sustaining, viable population. Fifty-one P. norfolcensis were fitted with radio transmitters and tracked intermittently between December 1997 and November 1998. Home ranges were small (1.3 - 2.8 ha), narrow (20 - 40 m) and elongated (322 - 839 m). Home ranges were mostly confined to the linear remnants, although 80% of gliders also utilised small clumps of adjacent woodland within farm paddocks for foraging or denning. Home range size was significantly larger at intersections between two or more linear remnants than within straight sections of linear remnants. Intersections appeared to be important sites for social interaction because the overlap of home ranges of members of adjacent social groups was significantly greater at intersections than straight sections. Intersections provided the only opportunity for members of three or more social groups to interact, while still maintaining their territories. The 51 gliders were radiotracked to 143 different hollow-bearing trees on 2081 occasions. On average, gliders used 5.3 den trees during the study (range 1-15), and changed den trees every 4.9 days. The number of den trees used by each glider is likely to be conservative because the cumulative number of den trees continued to increase over the full duration of the study. When gliders shifted between den trees, the mean distance between consecutive den sites was 247 m. Den trees were located throughout a glider's home range, thereby reducing the need to return to a central den site and potentially minimising energy expenditure. Dens were usually located in large trees (mean diameter 88.5 cm) and were selected significantly more often than expected based on their occurrence within the landscape. The overall conclusion of this thesis is that the linear network I studied provides high quality habitat for resident populations of arboreal marsupials. Important factors influencing the suitability of the linear remnants appear to be the high level of network connectivity, the location on soils of high nutrient status, the high density of large trees and an acacia understorey. In highly fragmented landscapes, linear habitats as part of the remaining woodland mosaic have the potential to be an integral component in the conservation of woodland-dependent fauna. The habitat value of linear strips of vegetation should not be underestimated.

Fisheries ecology of sand flathead in Port Phillip Bay

Age data revealed that growth of sand flathead samples caught within Port Phillip Bay is very different compared to those caught from outside the Bay. Results also show that recruitment is variable (dependent of several environmental parameter), and that this variability is largely responsible for trends in abundance.

Nutrient and phytoplankton status of Lakes Purrumbete and Bullen Merri, western Victoria

The thesis investigates two adjacent volcanic maar lakes, with differences in chemical and biological properties. Lake Bullen Merri a brackish, phosphorous-limited lake that suffers from nuisance algal blooms and Lake Purrumbete a fresh, nitrogen-limited lake with diverse phytoplankton assemblage. Nutrient fluxes for both lakes are dominated by internal cycling.

Population ecology and captive breeding of Pseudomys novaehollandiae at Anglesea

The New Holland Mouse is critically endangered within Victoria. A decline in the species abundance resulted from below average rainfall and structural changes to habitat vegetation. A captive breeding program was established as part of the species recovery plan. Induced breeding throughout the year, under controlled conditions, was limited by the species aggressive behaviour.

Inter-relationships between riverine fish species and catchments, southeast Australia

The study investigated fish community characteristics in relation to environmental characteristics and impacts of introduced fish species in basins within Victoria and New South Wales, Australia. A wide variety of environmental characteristics influenced fish distributions over the area investigated including biogeography, land and water exploitation, basin size and morphology.

Toward sustainable forest management : the potential contribution of timber certification and product labelling in Victoria

Sustainable forest management has emerged as a major international forestry issue. This research assessed the potential contribution of certification and labelling to sustainable forest management in Victoria. The results indicate a potential demand for certified forest products and a consumer willingness to pay to ensure forests are managed sustainably.

Nutrients, palaeolimnology and cyanobacterial blooms in Lake Wallace, Western Victoria

The basic limnology, nutrient and hydraulic budgets and recent history (using fossil remains in the sediments) of Lake Wallace have been studies to determine factors that predispose the lake to the development of potentially toxic algal blooms.

Spatial ecology of sooty owls in south-eastern Australian coastal forests : implications for forest management and reserve design

We investigated the home-range size and habitat use of eight Sooty Owls (Tyto tenebricosa tenebricosa) in coastal forests in East Gippsland, Victoria, Australia, between November 2006 and January 2008. The size of home-ranges varied widely; based on 95% adaptive kernel estimates, the average size of home-ranges of males was 3025ha (±1194s.d., n=3), whereas that of females was 994ha (±654s.d., n=5). Sooty Owls utilised a broad range of ecological vegetation classes and topographical features for roosting and foraging at a greater scale than previously assumed. There was minimal selection for habitat types based on floristic composition, primarily only avoiding heathlands (for foraging and roosting) and selecting particular dense foliage (rainforest and riparian scrub) for foliage roosting. Two Owls maintained home-ranges close to logged areas, with logging regrowth (<45 years old) being strongly avoided by both individuals. We recommend that the size of individual reserves for Sooty Owls in commercial forests should be increased to more closely resemble the core spatial resource requirements needed by a pair. Reserves should be largest where they feed predominantly on hollow-dependent prey. Most importantly, rather than conservation measures just focussing on the spatial requirements of Sooty Owls, efforts should be directed towards retaining high densities of crucial resources, such as hollow-bearing trees and mammalian prey species throughout the landscape.

Marine protected areas of the central Victoria bioregion

Along Victoria’s coastline there are 30 Marine Protected Areas (MPAs) that have been established to protect the state’s significant marine environmental and cultural values. These MPAs include 13 Marine National Parks (MNPs), 11 Marine Sanctuaries (MSs), 3 Marine and Coastal Parks, 2 Marine Parks, and a Marine Reserve, and together these account for 11.7% of the Victorian marine environment. The highly protected Marine National Park System, which is made up of the MNPs and MSs, covers 5.3% of Victorian waters and was proclaimed in November 2002. This system has been designed to be representative of the diversity of Victoria’s marine environment and aims to conserve and protect ecological processes, habitats, and associated flora and fauna. The Marine National Park System is spread across Victoria’s five marine bioregions with multiple MNPs and MSs in each bioregion, with the exception of Flinders bioregion which has one MNP. All MNPs and MSs are “no-take” areas and are managed under the National Parks Act (1975) - Schedules 7 and 8 respectively.

This report updates the first Marine Natural Values Study (Plummer et al. 2003) for the MPAs in the Central Victoria bioregion on the central coast of Victoria and is one of a series of five reports covering Victoria’s Marine National Park System. It uses the numerous monitoring and research programs that have increased our knowledge since declaration and aims to give a comprehensive overview of the important natural values of each MNP and MS.

Urban ecology and the future of cities

The role of ecology in a sustainable future is prominent in the media, academic writing and political decisions; as such environmental pressures, as well as economic, social and political, increasingly influence planning for the future. This paper looks at how this translates into the process for planning future cities – highlighting gaps in knowledge and issues of implementation. It draws on interdisciplinary sources to explore three main elements of the debate: What is urban ecology and why is it important to sustainable cities?; What gaps are there in the ecological knowledge of planners and policy makers and why are there gaps?; and How can urban ecology be integrated into the planning of future sustainable cities?. This paper does not aim to provide a definitive answer to the problem; rather it addresses the first two areas and identifies potential directions for the third. It takes Australia, as national, Victoria, as regional and Geelong, as local, points of reference.

The biology and ecology of the ocean sunfish Mola mola : a review of current knowledge and future research perspectives

Relatively little is known about the biology and ecology of the world’s largest (heaviest) bony fish, the ocean sunfish Mola mola, despite its worldwide occurrence in temperate and tropical seas. Studies are now emerging that require many common perceptions about sunfish behaviour and ecology to be re-examined. Indeed, the long-held view that ocean sunfish are an inactive, passively drifting species seems to be entirely misplaced. Technological advances in marine telemetry are revealing distinct behavioural patterns and protracted seasonal movements. Extensive forays by ocean sunfish into the deep ocean have been documented and broad-scale surveys, together with molecular and laboratory based techniques, are addressing the connectivity and trophic role of these animals. These emerging molecular and movement studies suggest that local distinct populations may be prone to depletion through bycatch in commercial fisheries. Rising interest in ocean sunfish, highlighted by the increase in recent publications, warrants a thorough review of the biology and ecology of this species. Here we review the taxonomy, morphology, geography, diet, locomotion, vision, movements, foraging ecology, reproduction and species interactions of M. mola. We present a summary of current conservation issues and suggest methods for addressing fundamental gaps in our knowledge.

From ecological creativity to an ecology of well-being: 'flows & catchments' as a case study of NVivo

This paper’s research question concerns how the ecological creativity of the Volcanic Plains region of Western Victoria may be transformed into an ecology of well-being of benefit to the local community. Drawing on the philosophies of Spinoza and Gilles Deleuze, we argue that community well-being results from the richness of connections and relationships made within a place. The case study for our investigation is ‘Flows & Catchments’, which is an ongoing, collaborative, creative-arts research project auspiced by Deakin University. Its modus operandi is Practice-Based Research (PBR), and its aim is to promote community well-being in Western Victoria. However, while the whole metier of the creative arts is to make the novel connections and relationships that should bring about community wellbeing, the various artists of ‘Flows & Catchments’ have proved slightly reluctant to make connections outside of their individual or small-group sub-projects. In this way, ecological creativity has not reached its full potential as an ecology of well-being because the rich connections and relationships essential to this well-being have not yet been fully realised. This paper explores the potential of using the NVivo qualitative analysis software package to bring together the creative-arts sub-projects of ‘Flows & Catchments’, as a way of fostering an ecology of well-being out of a currently dispersed ecological creativity.