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Sand mining on North Stradbroke Island has ceased 70 years after it became the Island’s major industry. This article reports conversations with local indigenous people who have lived on the Island ...

There are many definitions of ‘sustainability’, but the term exists within social, economic and environmental contexts, the ‘three pillars’ of sustainability. Although governments, business...

Together with other signatories of the Ramsar Convention, Australia is obliged to seek to halt wetland loss, which may include farm ponds/dams and other constructed wetlands. Since European arrival in Australia, extensive clearing of native ecosystems for agriculture and urbanisation has resulted in a concomitant loss of natural wetlands. However, there is limited information on changes in physical characteristics of wetlands with the transition to agriculture and urbanisation. In North-western Sydney, we investigated changes in wetland surface area, distance to nearest neighbour (connectivity), and shape complexity with transition from natural to agricultural and urban landscapes. There were significant differences amongst land use types for these three waterbody parameters. Wetlands in natural areas were larger and further apart from each other. Half the wetlands in agricultural and urban landscapes had small surface areas, but wetlands in agricultural areas were closer together, so connectivity for biota was potentially greater. Most wetlands in all land use classes were simple or irregular in shape, though urban areas had a higher proportion of irregular wetlands. We predict that on the current trajectory of increasing urbanisation, native biodiversity will continue to decline unless more emphasis is placed on the importance of wetlands – natural and constructed.

Groundwater-dependent ecosystems and their dependent species are under increasing threat globally. Petalurid dragonflies are one such group. This review highlights processes that threaten the groundwater-dependent mire habitats of Petalura gigantea, a dragonfly with long-lived fossorial larvae. The species is reliant for successful reproduction on areas of emergent seepage, or at least, on a water table that is sufficiently high to cause saturation of the peaty substrate. These microhabitat characteristics are critical for successful oviposition and larval burrow establishment, making the species particularly vulnerable to any lowering of water tables. The effect of any lowering of water tables, due to groundwater abstraction or longwall coal mining, for example, will be compounded by the effects of more intense fire regimes in these mires and by projected climate change. These threatening processes act in conjunction with a range of other anthropogenic threats and are mirrored globally in threats to other groundwater-dependent mire ecosystems and their dependent species, including other petalurid dragonflies.

An estimated 50 % of the world’s population live in urban areas and this is expected to rise to 70 % by 2050. Urban developments will thus continue to encroach on non-urban landscapes and native biodiversity (flora and fauna). Although much has been written on sustainable urban development, the biodiversity component has been largely ignored. Consequently, sustainable development of biodiversity is poorly understood within urban confines by planners and designers, community developers and social planners, activists and social movements, and even academics and consultants. When native flora and fauna are incorporated deliberately or ad hoc, for example due to landscaping fashions, the outcome may create on-going issues for authorities which could be minimised with sustainable management. For example, green urban infrastructure including parks and gardens, ‘backyards’, remnant bushland and even wastelands can be more effectively developed to sustainably support biodiversity, typically at reduced on-going cost. However, due to the lack of understanding of this aspect of sustainable development and on-going issues of ‘pest management’, the focus has been on only a small sub-set of the overall biodiversity. In addition, these changes in species’ dynamics often lead to the decline of local amenity for humans, and endemic species (e.g., small-bodied birds). Other taxa are typically neglected because they are cryptic, innocuous, dangerous, a nuisance, feral, or just not ‘sexy’.

Increasing numbers of retirees seek individual, extended, unstructured activities in remote, non-commercial locations. Travel is predominantly by self-drive 4WD vehicle towing a caravan/campervan. These ‘grey nomads’ often prefer remote bush camping sites/caravan parks to commercial resorts. The tropics – a popular destination – are inhabited by Australia's only large semi-terrestrial carnivore, the estuarine crocodile Crocodylus porosus. Conservation programmes of recent decades have resulted in a substantial increase in numbers. With naive grey nomads increasingly encroaching on crocodile territory, attacks are expected to increase. Review of conservation programmes to incorporate awareness education targeting grey nomads is therefore required.

Australia and North America have many similar cultural features. Yet, although North America has a strong recreational hunting culture, the sport is limited in Australia. This paper investigates why this difference may have developed. It appears that a major difference is the reason for settlement: Europeans were attracted to North America because of its abundant wildlife and the socio-economic value of furbearers already established, whereas Australia was settled as a penal colony. The colonists found Australia’s wildlife was scarce and unfamiliar, offering no prospect of socio-economic gain from hunting furbearers. With over-exploitation, both continents moved to conservation of their wildlife. North America developed a conservation ethic based on a social, utilitarian approach to sustainable management of furbearers. Australia embraced a holistic approach to conservation to protect biodiversity. The differences, therefore, result from zoological differences and not innate cultural difference.

Testis volume is generally correlated with sperm production. Their size is, therefore, considered informative, and is widely used as a surrogate for reproductive ability in a range of species. Gonadal abnormalities that influence adult reproductive function as a result of endocrine disruption compounds (EDCs) have been reported. In response to the observation that the population of the bearded dragon Pogona barbata had crashed in peri-urban Western Sydney, we investigated the nature and extent of testis deformity. It was observed that individuals collected in Western Sydney since the introduction of unleaded petrol in 1985 have a high level of deformities that are consistent with disruption of the endocrine processes. While deformities, such as missing testes, extreme asymmetry between testes, and flattened testes were not associated with any single aspect of the reproductive cycle, and they were found across the range of the species, the problem was much greater in Western Sydney than elsewhere in the sp...

Deer are not endemic to Australia, but were introduced for game and aesthetics between the early 18th and 20th centuries. Until recent decades, most deer descended from these introductions. Before the 1970s when deer numbers and distribution expanded dramatically, farming was a modest enterprise. With the collapse of farming in the 1990s, large numbers of deer were deliberately released and translocated. Feral numbers and herds have subsequently expanded, and are increasingly encroaching on urban areas. As a new issue in Australia, views toward feral deer are polarized and span “welcome guest” to “major pest.” The emerging urban deer issues need greater acknowledgment and strategic management. This will require more emphasis on raising awareness, engagement with stakeholders, and development of legislative instruments to provide better strategic management of urban deer. This article reviews the potential increase in urban deer in Australia, considers the associated issues, and provides recommendations fo...

‘Water in The Landscape’, a community cultural development programme, focused on urban water management in Western Sydney (Australia). This case study was influenced by research which found provision of expert information alone increases community resistance to engagement, and called for methods using visual–practical elements to provoke people to question their values and attitudes, thus preparing them to absorb new information. Our programme used strategies, at a large scale (15 cultural projects), over two years, supported by local deliberative forums, and online information and dialogue facilities. We present outcomes of the cultural projects’ component of the programme, assessed in partnership between local government and University of Western Sydney.

Sport is important internationally; but in Australia, it is part of the national identity. The enjoyment of public open space for sport is, therefore, an assumed community right. We interviewed key staff from inner Sydney councils about management issues associated with public open space. The greatest concern was sporting fields – formal and informal – which were considered to have exceeded carrying capacity mainly because of the unintended outcomes of government programmes/policies spanning; (1) ‘healthy lifestyles’ which increased public open space use; (2) ‘urban consolidation’ increased inner-city population density with associated increased usage and loss of open space; (3) ‘temporal water restriction’ during drought (not ‘water budgets’) which intensify management issues; and (4) ‘building the education revolution’, meaning that public open space lost from schools results in increased pressure on public open space. Consequences have increased human pressure on public open space without commensurate ...

While presence/absence of endocrine disruption has been widely observed within polluted wetlands, relatively few data have addressed population level changes for any species. This paper investigated the effects of endocrine disruption on the phenotypic sex ratio, size structure, biomass, and density of Gambusia holbrooki populations in wetlands used for storage of 1) tertiary treated sewage effluent; 2) urban stormwater runoff; and 3) wetlands without effluent supplementation (control wetlands). Those wetlands that had previously been determined to have endocrine disruption effects on G. holbrooki had lower density and biomass of fish than other wetlands. In contrast, the pattern of variation in the average length and phenotypic sex ratio of fish was not consistent with the effects of endocrine disruption.

Emergence studies in Odonata provide information on the behaviour, ecology and fundamental demographic parameters in population studies. This paper reports on a study of sex ratio at emergence, pattern and duration of the emergence season, and potential cohort splitting in Petalura gigantea. Sex ratio at emergence varied among years, habitat patches and swamp types. Across all collections, sex ratio varied significantly from a 1:1 ratio, with a bias towards females. The duration of the emergence season varied between sites and years, from at least 45 to at least 70 days, potentially commencing by late October and extending into early January and possibly beyond. Although some evidence suggested cohort splitting, it was not confirmed. Observations of spatially and temporally aggregated emergence clusters are consistent with observed oviposition patterns of individual females, suggesting cohort emergence. Observations of mortalities at emergence and of emergence location are provided; the latter should assi...

Ectoparasitic and ectocommensal macroinvertebrates (epibionts) of turtles have received limited attention with species from most Australian chelids poorly known. In this paper we present observations on the taxa collected from the widespread and abundant Australian freshwater species Chelodina longicollis Shaw, the Eastern Long-necked Turtle, sampled from farm dams in North Western peri-urban Sydney. Twelve epibiont taxa were collected, with the most commonly encountered species being the leech Placobdelloides bancrofti McKenna and a chironomid. Encounter rates varied over winter, and with carapacal algal mass, and farm dam. In contrast, they do not show a preference based on turtle sex. Since C. longicollis of different size and sex show habitat selectivity within farm dams (Ryan and Burgin 2007), epibiont distribution is not due merely to opportunism.

In economically developed countries it is projected that by around 2015 over 50% of a person’s lifetime will become available for leisure. Demand for leisure needs, already strong, will continue to increase. One segment of the market, outdoor nature-based recreation (including tourism), is growing strongly worldwide. A substantial proportion of these activities are water-based. The associated demand for recreational vessels has increased rapidly in recent years and is projected to continue to trend upwards. Australian trends mirror those internationally. Using Australia as a case study, we review the direct physical, chemical and biotic impacts associated with recreational boating in coastal water environments. Major physical impacts include disturbance due to movement of craft in shallow waters (e.g., turbulence) and the effects of anchoring/drag, noise/interference/collision that impacts on wildlife. The most critical chemical impacts result from pollution due to fuels and oils, defouling treatments (even those not legislated in-country), and human waste (e.g., sewage effluent). Important biotic impacts are the potential continued introduction and secondary spread of non-native species. We conclude that while greater research effort will provide more environmentally benign products, with the increasing popularity of recreation vessels, it will be beyond the resources of Australian governments to police legislation effectively. However, based on Australian’s demonstrated engagement with government in terrestrial environmental management, with their deliberate engagement with the boating fraternity, the impacts of recreational boating would be lessened.

Vehicle collision resulting in animal mortality is a common daily occurrence, although few studies have considered the impact on herpetofauna in urban areas. Over a 7 year period (2003 - 2010), 1.4 km of suburban streets of Falconbridge that interface with the Greater Blue Mountains World Heritage Area, west of Sydney, was surveyed on foot two to four days a week, typically soon after dawn. Over the period a total of 86 reptiles that represented 20 species: 38% of the lizard and 56% of snake species known from the area were collected as road kills due to collision with vehicles. This equated to approximately one individual per month that was collected across the 7 years. Representatives of six frog species were also identified as road kills (33% of the local frog fauna). In Faulconbridge, 20-30 km of 50 km/hr roadways interface with the national park and there are 26 towns within the World Heritage Area. Each of these towns has a network of streets that covers much more than just the perimeter of the town...

In Australia, the adventure sport of canyoning occurs predominantly in the protected areas of the Greater Blue Mountains World Heritage Area, 50 km west of Sydney. It involves travelling through narrow, deep gorges using a combination of walking, abseiling, wading, rock scrambling and/ or swimming through the canyon streams. The sport’s popularity is reported to have increased substantially over time, causing concern for the sustainability of these fragile ecosystems. To investigate visitor impacts, benthic macroinvertebrate assemblages and water quality were compared among four canyons subject to high visitation (average 20 – 100 visits per week) with those in four unvisited/low visitation canyons (0 - 5 visits per week). Comparison was also made between impacted and nonimpacted areas within two of the high visitation canyons. Sampling was undertaken over two canyoning seasons (early spring to late autumn). No significant relationship between macroinvertebrate assemblage composition or water quality was observed due to visitation level within and among canyons, although there were inherent differences among canyons. Water quality was consistent with pristine conditions in all locations. Macroinvertebrate assemblages included a range of pollution sensitive taxa (e.g., Ephemeroptera represented by 42.3% of all animals). Although family richness was concentrated within a few orders (84.2% of families were represented by 50% of orders), most families were represented by 2 Recognisable Taxonomic Units, 47.4% of these were represented by a single taxon. We concluded that, at current visitation levels, there is no measurable impact on the predominant animal component of these ecosystems. This finding was contrary to the expectations of the land managers of this area.

Introduced species have made a major contribution to the degradation of aquatic wetlands throughout the world and particularly in Australia. One species, Red-Eared Slider Trachemys scripta elegans, classified among the world's top 100 most invasive pest species, has established populations in Australia, most extensively in South-eastern Queensland. A decade ago a small established population was identified in a wetland in Southern Sydney in Yeramba Lagoon. We re-visited this population a decade on to determine its status and the impact on the two resident native freshwater turtle species, Chelodina longicollis Eastern Long Necked Turtle and Emydura macquarii dharuk Sydney Basin Turtle. We captured similar numbers of red-eared sliders as a decade before but increased number of the two native species. There was therefore no indication that the feral species was currently at a competitive advantage over the native species.

The disruption of endocrine systems due to environmental contaminants potentially impacts on developmental, behavioural, regulatory, and reproductive systems of wildlife. A major source of exposure of wildlife (terrestrial and aquatic) to endocrine disrupting compounds is through contact with contaminated surface waters. Current testing routines in aquatic systems have not been designed specifically to assess endocrine disruption properties or, alternatively, methods tend not to be fully developed. An alternative approach is to use a response sensitive to these chemicals such as gonopodium length in the pest species Gambusia holbrooki as an indicator. This species was used as a surrogate for native aquatic species to assess endocrine disruption in wetlands that are used for the storage of stormwater or treated sewage effluent. These were compared with adjacent wetlands used for watering stock (farm dams) that were not contaminated with these pollutants. Deformities in the mosquito fish were found that wer...

Abstract Over time native vegetation remnants in urban areas are typically eroded in size and number due to pressures from urban expansion and consolidation. Such remnants, frequently neglected and invaded by weeds, may constitute the last remaining habitat for some species' populations in urban areas. In the restoration of remnants for biodiversity, weed removal is often a high priority but there is a dearth of information on the role that exotic vegetation plays as habitat for fauna such as small reptiles. We investigated the vegetation type preference of urban remnants at the edge of a Sydney golf course by Amphibolurus muricatus, the native jacky lizard. The three vegetation types present were Eastern Suburbs Banksia Scrub (an Endangered Ecological Community) with sparse groundcover, dense stands of the introduced Eragrostis curvula African love grass, and open fairways of lawn: three structurally different habitats. Captured jacky lizards were spooled and their movements traced by following the thread left as they moved through their home range. Jacky lizards preferred areas that afford them most cover. While they foraged throughout the stands of love grass, they tended to avoid the edge of native vegetation remnants. They also basked on the lawn close to the vegetation where they had recently foraged, or traversed it to enter natural vegetation or grass. We concluded that introduced love grass offered additional habitat because of the relatively dense vegetation cover, and that areas should not be managed with the assumption that invasive weeds are detrimental to native species without appropriate assessment.

Perceived growth in the adventure recreation sport of canyoning in the Greater Blue Mountains World Heritage Area (Australia) has raised concerns with park management that such activity is resulting in unsustainable visitor impacts to canyon ecosystems. Three levels of trampling intensity were applied within an upland section of a canyon stream to assess the impact of trampling on benthic macroinvertebrate communities. After an initial detrimental effect from trampling, there was a rapid recovery of the macroinvertebrate community. Recovery occurred within one day of trampling ceasing, and overall community composition was similar among treatments after 15 days. However, by day 15 the untrampled sites showed a substantial decrease in animal abundance. This indicated that adjacent habitat contributed greatly to the recolonisation of animals into trampled areas.

We examined how the background (urban/rural) of 282 tertiary students influenced their attitudes and actions including their use of natural areas. Most considered that protection of natural spaces was ‘important’. Childhood residence influenced time spent in natural areas as young adults. When time spent in natural spaces was compared with residence status, non‐urban dwellers more frequently visited natural areas than urban dwellers. Rural residents who visited natural spaces were likely to visit more frequently than urban dwellers. The different types of passive recreation carried out in natural spaces and whether the student was involved in environmental restoration activities were not matters influenced by residence status, although there was a difference as between passive or active recreation in natural spaces. Over 80% of participants considered that ‘protection of the natural environment’ was more important than the cost of fresh produce, reduced taxes, fuel prices or ‘better use of recycled material’.

Internationally, waterways within urban areas are subject to broad-scale environmental impairment from urban land uses. In this study, we used in-stream macroinvertebrates as surrogates to measure the aquatic health of urban streams in the established suburbs of northern Sydney, in temperate south eastern Australia. We compared these with samples collected from streams flowing in adjacent naturally vegetated catchments. Macroinvertebrates were collected over a 30-month period from riffle, edge and pool rock habitats and were identified to the family level. Macroinvertebrate assemblages were assessed against the influence of imperviousness and other catchment and water quality variables. The study revealed that urban streams were significantly impaired compared with those that flowed through naturally vegetated non-urban catchments. Urban streams had consistently lower family richness, and sensitive guilds were rare or missing. We found that variation in community assemblages among the in-stream habitats (pool edges, riffles and pool rocks) were more pronounced within streams in naturally vegetated catchments than in urban waterways.

As the driest inhabited continent, Australia faces pressing issues of water quality and quantity. A recent decade of drought has heightened interest. We surveyed a community on the Hawkesbury–Nepean floodplain, the river that provides most of Sydney’s potable water. The survey targeted respondents’ perceptions of the source of water in local wetlands, causes of water pollution, their willingness to undertake environmental action to improve water quality, and their preferred source of information to inform remedial action. Residents considered that the environmental health of the local waterways was important, and they stated that they were willing to change their habits for environmental improvement. We observed that the first step to environmental stewardship was widespread (although strongest in women) but understanding of issues and the reality of moving from rhetoric to action was less well developed.

Several studies, particularly in the Northern Hemisphere, have demonstrated that chironomids are responsive to pollution (e.g., heavy metals, organic). In Australia, there is limited evidence that chironomid species have differential sensitivities to water pollution, with several studies reporting high tolerance of heavy metal pollution. We investigated the impact of both zinc-rich mine waste and organic effluent on chironomids within an effectively pristine background using the Chironomid Pupal Exuviae Technique (CPET). Chironomid species assemblages were strongly influenced by both mine drainage and organic pollution. Community composition differed between unpolluted streams and locations downstream of the pollution sources, and between the two different sources of pollution. Thirty seven of the most abundant species exhibited strong responses to water pollution varying from greatly increased abundance to complete absence. Ten species had higher abundance at one of the polluted sites compared to unpolluted sites; six in the presence of zinc pollution and five in the presence of organic pollution. One species responded positively to both pollution types. Our results indicate that contrary to the mixed reports of Australian chironomids for being insensitive to pollution, we found that they displayed a strong pollution response to both organic and heavy metal contamination.

We assessed diurnal variation of Chironomidae exuviae in two small upland streams in temperate Australia, during summer. Understanding the diel periodicity of exuviae can be an important consideration for biomonitoring purposes or to investigate adult emergence patterns. We collected 1,813 floating exuviae, comprising 54 taxa from four subfamilies, from flowing water using a drift net. Unlike many northern hemisphere temperate studies, we observed that peak exuviae abundance (7.3 exuviae per m³) and taxon richness (1.7 taxa per m³) occurred in the dusk and night hours, with the lowest numbers (0.9 exuviae per m³) and taxon richness (0.6 taxa per m³) recorded in the late morning to early afternoon. We suggest that this could be an adaptation to avoid stressful weather during the heat of summer days, or it could be to avoid visual predators. The numerically dominant taxa exhibited peak abundance in the dusk/night samples which indicates predominant crepuscular/nocturnal patterns of adult emergence. This pattern was consistent across both streams surveyed. Our taxon inventory rose steeply during the first 24-h occasion, then at a reduced rate during the second and third days of sampling. For flowing water collections of exuviae that utilise drift-netting, we suggest that sampling at all sites includes at least three 24-h cycles and avoids periods of heavy rainfall and increased stream flow.

In many countries the ubiquitous farm dam or pond is an integral component of agricultural landscapes. In Australia there are in excess of half a million farm ponds, used largely for irrigation or for watering stock. In contrast to Europe, these wetlands are being decommissioned in response to the introduction of government policy that regulates water usage from these dams. They are also being in-filled with expanding urbanisation without consideration of their benefits as reservoirs of biodiversity. We compared the diversity of macroinvertebrates in farm dams with nearby stream habitats on a cool temperate tableland in central New South Wales. There was greater diversity in-stream than in the dams; however, dam sites showed a larger mean diversity and total diversity per site than in-stream. Species recorded in-stream were more frequently represented by single individuals while species were recorded more consistently in dams. We also observed that macroinvertebrate assemblages were more similar to those in the same dam in different seasons than to adjacent dams in the same season. Some species recorded had not previously been recorded from farm dams. In contrast to the general consensus that Australian farm dams are homogeneous environments with a range of common widespread species, we showed that they provide a variety of sustainable reservoirs of biodiversity within the landscape. They also have the potential to provide ‘stepping stones’ between undisturbed and modified habitats, in part countering the fragmentation that occurs as a result of agricultural practices.

Biodiversity offsets are voluntary conservation activities that are designed to offset residual, unavoidable damage to biodiversity caused by development activities. The concept is also known by terms such as setasides, compensatory habitat, and mitigation banks. Recent legislation in New South Wales (Australia) provides an additional legislative tool in the attempt to counter balance biodiversity loss due to expanding urbanisation. A key role is played by the consultant ecologist who is at the interface between other vested interests: governments, the legal system, developers, and landholders wishing to trade biodiversity credits. In this paper we reflect on the role of the consultant ecologist in the biodiversity offset (“BioBanking”) process, and touch on some of the pitfalls including the lack of knowledge of the function and components of most ecosystems, the immaturity of the scientific disciplines that underpin decision making, and problems on ensuring integrity of objectivity and independence in s...

In golf course development there is frequently remnant vegetation on the areas unused for infrastructure. We propose that these areas, together with a whole range of other reserves including sporting fields, cemeteries, railway reserves and educational facilities may be the source of degraded remnant vegetation and associated open space that could be used to provide offsets for biodiversity. We followed the changes in vertebrate biodiversity with low key alteration to management of the Camden Lakeside Golf Course to assess if such areas had the potential for biodiversity banking offsets. Birds, bats, frogs and reptiles increased in species diversity over time. Frogs and reptiles tended to peak in species numbers during the observational period but bat and bird diversity continued to increase. We concluded that on this ‘island’ within a matrix of urbanisation and cleared agricultural lands without remnant vegetation, observed changes in diversity made such areas potential sites for biodiversity banking offsets.

Summary 1. World wide, and in Australia, many frog populations have declined over the last two decades. The present study was undertaken to determine whether urbanization has affected frog diversity and abundance. 2. Five urban sites were paired with non-urban sites. Urban sites were in Katoomba and Blackheath, and were subject to physical environmental disturbance and impacted by storm water pollution due to urban runoff. Non-urban sites were in the Blue Mountains National Park and were effectively subject to no human impact. 3. Water quality at urban sites was typical of sites polluted with sewage, while non-urban sites exhibited water quality typical of ‘pristine’ natural bushland streams. 4. Six species were found at urban sites (Litoria peronii, Litoria dentata, Litoria verreauxii, Limnodynastes dumerilii, Limnodynastes peronii, Crinia signifera), with up to four species present at a site. Only one species (C. signifera) was recorded at non-urban sites, and frogs were absent from most non-urban sites. 5. The situation in non-urban sites mirrors the trend of decline observed in other montane regions. Surprisingly, frog abundance and diversity were higher in urban habitats, running counter to this trend. 6. We hypothesize that the salts, detergents and other chemicals in urban wastewaters provide frogs with a level of protection against disease, particularly chytridiomycosis.

The influence of weirs on the distribution of freshwater mussels was investigated in the Hawkesbury-Nepean River, Australia. Distribution of species and densities of size classes were strongly correlated with catchment level factors (e.g. location around a major impoundment, stream order). At catchment scale, weir height, presence of a fish barrier, fish ladder type and position above or below small weirs did not influence the presence/absence of mussel populations. Lower mussel densities in the upper catchment may therefore reflect inhibition of host fish migration. Where present, weir height and geomorphic reach type were linked to differences in densities among species. Geomorphic reach-based differences were reflected by the Hyridella species, but not Velesunio ambiguus. When population structure was described by size class distribution, there were significant differences between densities of small and medium mussels from weirs above, compared to weirs below, a major impoundment, but not for large mussels. Upstream populations may therefore be functionally extinct. Distribution of mussel size classes differed among geomorphic reach types with highest densities for each class found in the least human-impacted reaches. Small mussels were almost invariably found below the major impoundment, most frequently below weirs. Distribution patterns were inconsistent across species, suggesting habitat preference. V. ambiguus and Hyridella australis were most abundant in shale reaches, where assemblages were influenced by fish ladder type. Hyridella depressa and H. australis dominated in sandstone gorges and straights with assemblage density related to weir height. In upper catchment sandstone reaches, mussel assemblages comprising predominantly V. ambiguus were influenced by fish ladder type and weir height. While multiple factors defined localized distribution, large impoundments were linked with reduced population densities. The probable mechanism is the restriction of host fish movement and resulting lack of recruitment. In the Hawkesbury-Nepean River, smaller weirs also seriously impacted recruitment. Copyright © 2008 John Wiley & Sons, Ltd.

Alligator weed, Alternanthera philoxeroides (Martius) Grisebach, of the family Amaranthaceae, has become a weed in many countries outside of its natural range in South America. In Australia, it is classified as a weed of national significance because of its potential to devastate agricultural and natural ecosystems. In New South Wales, the weed management officers of local government areas are charged with its control. In 2007, we surveyed this group to determine the status of alligator weed in each jurisdiction and to determine the methods and resources used in its control. Half of the local government area officers who responded reported its presence. The age, number, and size of the infestations indicated that the weed continues to spread into new areas, and is well established in others, at least within local government areas. The resources provided for the weed's management across the local government areas was less than had been expended annually on its removal from a single swamp. The respondents acknowledged that the current approach was inadequate and the need for research into its management was identified. We conclude that, with current management, the weed will continue to spread and recommend that the community should be mobilized to identify new areas of infestation and appropriately train people (e.g. bush restoration consultants, Landcare groups) to remove the weed.

1. Australian freshwater turtles are widely distributed throughout the continent, and in each river catchment there are at least two taxa. In south-eastern Australia Chelodina longicollis and forms of Emydura macquarii co-habit within a waterway, although they have been shown to partition habitat within the water column in non-urban bodies of water. Limited comparative data are available for the urban populations. 2. Within urban Sydney C. longicollis (eastern long-necked turtle) and Emydura macquarii dharuk (Sydney short-necked turtle) share habitat. However, in contrast with non-urban studies of C. longicollis and other sympatric E. macquarii taxa, it was observed that the population profile of the two species was similar at all sites, and that C. longicollis were present in greater numbers than E. m. dharuk. 3. The continued degradation of preferred habitat, low recruitment, and potential competition from introduced turtles place both species in a precarious position. 4. The shallow, impounded waterways of the regulated urban bodies of water align more closely with the preferred habitat of C. longicollis than with that of forms of E. macquarii, which prefer deeper flowing waters or large wetlands adjacent to rivers. Emydura m. dharuk may be at greatest risk of extinction in urban areas. 5. Across urban Sydney, the low numbers of E. m. dharuk compared with C. longicollis may be due to the lack of mobility of E. m. dharuk such that individuals tend to be stranded in sub-optimal habitat. In contrast, C. longicollis has a greater propensity for overland movement, and a preference for the ‘new habitat’ resulting from urban impacts on the associated waterways, and thus appears to be able to utilize these modified urban waters more successfully. Copyright © 2008 John Wiley & Sons, Ltd.

1. Microhabitat preferences of freshwater mussels and associated substrate characteristics were investigated across a range of geomorphic reaches in the Hawkesbury–Nepean River, Australia. 2. The structure of substratum patches available was strongly influenced by geomorphic reach type. In each reach type, mussel distribution was most frequently correlated with coarse sand and a roughness element characteristic for that reach. Roughness elements such as boulders and cobbles create a flow refuge and were linked with mussel size. 3. Small mussels tended to be associated with boulder-stabilized habitats and medium sized mussels with cobble habitats. Large mussels rarely co-occurred with any particular roughness element. Individual species were strongly linked to geomorphic reach type. This association may be due to species' differences in ability to colonize available microhabitat types. 4. The highly tolerant Velesunio ambiguus dominated shale reaches, characterized by fine sediments and human impacts. In contrast, Hyridella depressa dominated in gorges, utilizing small flow refuges among boulders, while H. australis were present in low densities across a range of substrate conditions. 5. The persistence of multispecies assemblages in mussel beds throughout the Hawkesbury–Nepean River implies similar niche utilization among species. Partitioning of habitats across species on the basis of size suggests some degree of habitat selection, or differential survival. At the local scale, microhabitat characteristics influenced the size distribution and densities of mussel assemblages. Continuing declines in mussel densities are likely to result from ongoing channel modification and increased siltation resulting from changes to riparian vegetation. Copyright © 2008 John Wiley & Sons, Ltd.

The predator–prey relationship plays an integral role in community structure. In the presence of habitat fragmentation, the dynamic interaction among co-existing species may be disrupted. In this paper we investigated the interaction between small skinks resident in open woodland remnants and the predatory birds that cross-forage between the remnants and the surrounding peri-urban matrix. Skinks were found in significantly fewer numbers in the edge of remnants compared to their core. In contrast, predatory birds were in largest numbers at the edge compared to the core of remnants. We found that there was a strong negative correlation between skink numbers and predatory birds (individually and combined) consistent with higher predation pressure in the edge compared to the core of remnants. Strike rates on decoys that mimicked skinks were also higher in the edge compared to core habitats, consistent with higher predation rates in this edge habitat.

The role of animals in seed dispersal is widely acknowledged and turtles have been reported to act as vectors. All reports of turtles dispersing seeds to date have been via endozoochrony. The first evidence of turtles being epizoochronic dispersers of seeds via their carapacial algal mat is reported here. Chelodina longicollis is widespread and abundant throughout most of the eastern fringe of mainland Australia and throughout the largest inland river system, the Murray Darling Basin. They are the most terrestrially mobile of the Australian freshwater turtles and they are the most indiscriminate in habitat choice, inhabiting the entire range of water bodies from rivers to small ephemeral wetlands. Our results showed that turtles with even moderate carapacial algae can act as vectors in the dispersal of seeds associated with wetlands. However, as C. longicollis is unlikely to be unique among the freshwater turtles in this regard, we conclude that epizoochory is likely to occur in other turtle species.

Offsets, first formalised in the United States of America in the 1970s for wetland mitigation, are now widely used globally with the aim to mitigate loss of biodiversity due to development. Embracing biodiversity offsets is one method of governments to meet their commitments under the Millennium Development Goals and the Convention on Biological Diversity. Resource extraction companies see them as a method of gaining access to land, while the community may perceive them as a way of enhancing environmental outcomes. In New South Wales, Australia, BioBanking legislation was introduced in late 2006 with the aim of ‘no net loss’ of biodiversity associated with development, particularly expanding urban and coastal development. The strengths of the legislation are that it aims to enhance threatened species conservation, and raise the profile of conservation of threatened species and habitats. Weaknesses include (1) the narrowness of the definition of biodiversity; (2) the concepts are based on a flawed logic and immature, imprecise and complex science which results in difficulties in determining biodiversity values; (3) likely problems with management and compliance; and (4) an overall lack of resources for implementation and long-term monitoring. It is concluded that the legislation is a concerted effort to deal with biodiversity loss, however, stakeholders have concerns with the process, and it is unworkable with the complexity of such ecosystems (compared for example to carbon credit trading), and underdeveloped disciplines such as restoration biology and ecology. Despite these criticisms, there is a need for all stakeholders to work to improve the outcomes.

Summary 1. Chironomids and chaoborids were collected across eastern Australia and Tasmania in dune, glacial, sinkhole and maar lakes. Based on sampling exuviae from these relatively undisturbed freshwater lakes, we observed that species richness on the Australian continent was substantially greater than previously reported, and challenge the long-standing view that chironomid species richness is depauperate in Australian lakes, compared with the northern hemisphere. 2. While chironomid species richness was equivalent across the four geographical regions sampled (tropical northern Queensland, Fraser Island, south-eastern mainland Australia and Tasmania), there were only five ‘cosmopolitan’ species found across all regions. In general, species distributions were more closely associated with geographical region than with lake characteristics, and there were species assemblage differences among biogeographical regions. More than half of the 134 identified species were restricted to a single geographical region. Overall, Tasmanian lakes had the highest proportion of locally endemic species. 3. Latitude and altitude more strongly influenced species assemblages than did lake chemistry, although species richness sometimes varied among lake geomorphic types within a region.

This study investigates the impacts on the Australian native eastern long-necked turtle Chelodina longicollis of wetland waters derived from (1) precipitation and groundwater flow and wetlands also supplemented with (2) irrigation runoff from agricultural lands, (3) tertiary-treated sewage effluent and (4) harvested stormwater. Influences of water quality parameters on population attributes of the turtle population are considered. A total of 951 C. longicollis were captured in a mark-recapture study over 8 months. Overall, a female sex ratio bias was observed, and a larger number of smaller turtles were found in wetlands not contaminated by recycled tertiary-treated effluent. Dissolved oxygen, temperature, surface area and emergent vegetation had the greatest impact on turtle population structure. The lower the dissolved oxygen, the smaller the surface area of the wetland, and the higher the percentage of emergent vegetation, the greater the number of juveniles present. Water quality parameters which would be detrimental to fish predators appear to provide a ‘safe haven’ for juvenile turtles at the most vulnerable life stage of turtles.

Recently, Australian interest in farm dams has focused on rates of harvest of surface waters (runoff), and the impact this has on nearby natural systems. Little research has been directed towards the role of these artificial water bodies in sustaining biological reserves within the wider ecosystem. Macroinvertebrate communities in three farm dams in the Central Tablelands of New South Wales were surveyed, and water quality variables were correlated with species richness and abundance. Community responses to habitat factors including sediment depth, stock use, vegetation and debris were also examined. Communities were described at several taxonomic levels in addition to allocation to trophic groups and primary functional feeding groups. Species richness and abundance of communities were found to vary between dams and between habitat types within dams. The extent of these differences was decreased when communities were described by either trophic status or functional feeding mechanisms. Habitats were influenced by water quality and by physical features of the habitat, with the two factors interacting to define equilibrium conditions. Localised conditions resulted in different macroinvertebrate communities. Physicochemical parameters that correlated most closely with communities included light penetration, chlorophyll-a and conductivity. Habitat factors that were most frequently linked with communities were sediment depth and canopy cover, with localised disturbances related to stock use affecting feeding groups rather than specific taxa. One of the major problems associated with increasing modification of landscapes by agriculture or urbanisation is the fragmentation of undisturbed habitats. Creation of joint aquatic and woodland habitats enhances biodiversity corridors. The recognition of the potential for farm dams as reservoirs of biodiversity and development of management practices that optimise this neglected biodiversity reserve may have much wider benefits biologically, aesthetically and productively.

I investigated whether exotic turtle species were capable of establishing breeding populations in the Sydney area and confirmed that two exotic species were present: Trachemys scripta elegans and Clemmys marmorata. Mature females of both species were recorded with shelled eggs in the oviducts and evidence of nesting by T. s. elegans species was noted. Trachemys scripta elegans were observed in a range of sizes which suggested that it has established a foothold, at least in southern Sydney. Competition from this exotic species could have a detrimental impact on the local species, Chelodina longicollis and Emydura macquarii dharuk.

1. The Hawkesbury-Nepean River provides potable water for 5 million people living in the Sydney basin, and water for agricultural and horticultural production that meets most of Sydney's daily needs for fresh food. Anecdotal evidence indicated that numbers of freshwater mussels have seriously declined in much of the river over recent decades. 2. A field survey revealed the presence of populations of three species of mussels, Hyridella depressa, Hyridella australis and Velesunio ambiguus in the river. Higher density mussel populations were most common in catchment areas with little human modification to the channel bed or adjacent vegetation communities. 3. Levels of disturbance of riparian vegetation and, to a lesser degree, land use, were identified as being strongly associated with the absence of mussels from some reaches. 4. Catchment geomorphology was also shown to be relevant to the abundance, population structure and suite of mussel species present in different geomorphic reaches of the river. Absence of mussels was noted from areas where they had been recorded in previous studies. These results demonstrate that mussel species are under threat in the catchment. 5. As filter feeders with the ability to remove excess nutrients and bioaccumulate toxic substances, freshwater mussels play an important role in natural remediation processes in freshwater systems. 6. The decline in mussel populations in the Hawkesbury-Nepean River highlights concerns for the overall health of the river system, and supports the need to identify the subsidiary impacts of physical habitat modification in developing both riverine and riparian management strategies. Copyright © 2006 John Wiley & Sons, Ltd.

This study assesses the risks in ecological restoration arising from transplanting into soil containing glyphosate residues. Four Australian restoration species were grown for 60 days in nonadsorbing media treated continuously with glyphosate to establish threshold concentrations for damage. Visual signs of injury were observed in three species, and severe effects on root growth in all species, at solution concentrations as low as 18 mg/L. Only the perennial grass Themeda sp. died at this concentration, with other species surviving at concentrations in the range 36–360 mg/L, beyond which all plants died. Fourteen days exposure followed by removal of glyphosate from root media produced similar effects. Field and glasshouse experiments with the relatively tolerant tree species Angophora costata showed that application rates in the range 10–50 L/ha of herbicide product (360 g/L) would be needed to sustain damage to young plants transplanted into soil typical of local restoration sites. The volume of spray delivered using a handoperated sprayer varied between operators by 5- and 10-fold to complete the same tasks, at the high end presenting a potential risk to the most tolerant species under field conditions, even when spray concentrations follow label instructions. For all but the most sensitive species, the risk of glyphosate residues in ecological restoration should be minimized by training operators of unregulated applicators to deliver controlled volumes of herbicide when spot spraying prior to transplanting.

Seven potential anuran breeding sites within Western Sydney were sampled between March and August 1997 to assess the effect of habitat disturbance upon species assemblages. The greatest species diversity and abundance was recorded in relatively less human impacted areas, than in more disturbed sites. Of the seven species recorded to chorus during cooler months, only Limnodynastes peronii successfully breed and only in disturbed sites. The species was also more abundant in such areas than more pristine habitat. Oviposition time influenced larval growth rate, although there was no defined trend over time. Intra-clutch variation in weight achieved (over 10 weeks) was greater than among clutches. Ability to take advantage of breeding habitat that is sub-optimal for other species, the ability to breed year around and larval growth plasticity have apparently pre-adapted this species to thrive in urban impacted habitat, in contrast to most local endemic species.

Habitat fragmentation due to clearing often results in an increase in edge areas compared with overall remnant size, but there are limited data on the influence of increased edge areas on generalist species. Therefore, the abundance of small (

Limnodynastes peronii was observed to successfully breed in small urban impoundments. Fecundity, egg viability and hatching success varied significantly, spatially and temporally. The predominant influence on breeding success was therefore deduced to be environmental. In contrast, growth varied more within populations than over time or between waterbodies and the observed results were considered to reflect genetic, rather than environmental, differences. Abnormalities were also hypothesised to reflect genetic differences and not environmental conditions.

The foraging ecology of Red Wattlebirds, Anthochaera carunculata, and Noisy Friarbirds, Philemon corniculatus, was compared across central eastern New South Wales. Both species forage significantly more frequently on Eucalyptus punctata, relative to its abundance, than on any other species in all sites and seasons. Noisy Friarbirds were often absent from sites with E. punctata when Red Wattlebirds were present and foliage gleaning.

This study examines the level of isolation of arthropod faunas present on specimens of the endemic woodland tree Melaleuca linariifolia by investigating the recovery of faunas after defaunation using insecticide. One tree from each of 21 pairs of trees was sprayed at the beginning of the project (early April 1994). After predetermined periods, three test trees were resprayed along with matched control trees. A total of 95 154 arthropods were collected and sorted during the project. The number of species present on the trees recovered within 16 weeks of spraying, with common species recolonizing within a fortnight. The rarer species both of mobile (Diptera) and relatively sedentary (Araneae) taxa reappeared at similar rates. Complete recovery of numbers occurred by week 8 after spraying. Evenness (as Simpson’s D) recovered over the first 2 months; however, both the number of individuals and the evenness continued to diverge from the pattern seen on the control trees until the end of the study. While the rate of movement of individuals and species was such as to provide an apparently complete set of replacement species within several months of perturbation, the structure of the community found on the trees was still seriously disrupted after 1 year. Comparison of the suites of species originally found on the trees with those found in the respray samples and the control samples showed that the set of colonizing species was no more similar to the original fauna of the tree than it was to those on the control tree. The relatively rapid colonization of the trees by a suite of rare species – not necessarily those that were on particular trees before perturbation – indicates that rarity was due neither to inability of the species to colonize the trees nor to the suitability of the trees for these species. Recovery of rare species was to a level similar to that found on the control trees. That the divergences from the controls continued (in number of individuals and in evenness), implies a definite connection between the different faunas of a tree and their partial isolation from fauna communities on other trees. Whatever the forces that maintain suites of species on each tree, it is not the ability of the species to reach and colonize trees, nor certain attributes of a tree, that make it suitable only for a particular subset of the species available. Trees are not isolated entities but neither are they part of a fully integrated community, either chronologically or spacially, and issues of scale are also likely to be important in understanding and estimating the dynamics and factors regulating biodiversity levels.

The estimation of the level of biological diversity is critical to conservation planning and management. In this paper, factors affecting arboreal arthropod biodiversity estimates are examined, namely, reproducibility between trees, the proportion of the foliage of a tree that needs to be sampled, the effects of placement position of collectors under the tree and geographical distance between sampled trees of the species Melaleuca linariifolia and M. decora. It was found that arboreal arthropod specimens are not randomly distributed on trees and that, on average, 33% fewer species and 52% fewer specimens occur on the northern (sunny) sides of the trees than on the southern sides. The placement of collectors therefore can radically affect the estimates obtained. The species area curve continued to rise for each host until the entire tree was sampled. The shapes of the curves obtained from the two hosts however, were markedly different and it is concluded that it is not possible to simply transfer protocols from one host species to another, very similar, host species. When the same collecting effort was applied, the same number of species were collected, though M. decora supports twice the number of species as M. linariifolia. Variations of as much as 50% were found between trees of the same species in the number of species present and none of the estimators of biodiversity richness, evenness or information gave consistent results. As a consequence of these observations, the use of changes in standard estimators in decisions related to the management of biodiversity need to be considered carefully. Complementarity, however, was found to be a useful and robust measure of similarity of faunas for both host species. A new descriptor of the geographical distribution of organismal biodiversity, the biodiversity neighbourhood, is described and two methods of measuring it, using either spatial autocorrelation or complementarity, are demonstrated.

Interpretation of trap bias in sampling freshwater turtles has previously relied on indirect methods. The data presented here provides the first comparison of a sample and total census of a waterbody. Eastern Longneck Turtles Chelodina longicollis Shaw were sampled in a 0.1 ha farm dam for three days immediately prior to drainage and a population census was subsequently carried out. Fyke nets proved to be an effective method of sampling the population. During the sampling phase 78% of males (n = 11) and 81% of females (n = 21) were captured, and there was no significant difference between the sample and the census in terms of population size structure (χ23 = 1.12, excluding juveniles) or sex ratio (χ21 = 0.008). None of the three resident hatchlings were captured despite a high probability of capture (p = 0.67). Hatchlings and juveniles combined made up 19.4% of the population and there were no immature resident females and few immature males. Based on the population profile, recruitment was intermittent ...