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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’.

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.

The disruption of endocrine systems due to environmental contaminants potentially impacts on the developmental, behavioural, regulatory and reproductive systems of animals. A major source of exposure of animals (terrestrial and aquatic) to endocrine-disrupting compounds is through contact with contaminated surface waters contaminated with sewage effluent and/or stormwater discharge. We studied the response to endocrine-disrupting compounds of Gambusia holbrooki mosquito fish resident of wetlands that were used for the storage of either treated sewage effluent or stormwater runoff. We found that fish from wetlands that received polluted waters directly from the source (treated sewage effluent or stormwater runoff) demonstrated a morphological response consistent with endocrine disruption. In contrast, fish in the second in the series of wetlands that housed treated sewage effluent did not show evidence of such response. However, those from the second in the series of stormwater receiving wetlands did display a morphological response, although it could be considered milder than was observed in fish from the first in this effluent stream. Fish were also smaller in the wetland that received sewage effluent directly from the sewage treatment plant than elsewhere. Although the differences were not statistically significant, the average size of fish in the first in the series of stormwater wetlands were also small and second only to those in the first sewage effluent wetland.

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.

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.

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.

First developed in the USA in the early 1970s, ‘wetland mitigation banks’ provide a framework for conservation activities that are designed to offset residual, unavoidable damage to the natural environment caused by development activities. The concept is now a worldwide phenomenon. In this paper I consider the level of success of wetland mitigation banks in the USA for biodiversity conservation with a view to informing ‘best practice’ in Australia. I conclude that although the concept has merit, even in the USA where the processes have been evolving for over 30 years, the outcomes frequently fall short of the target of a ‘like for like’ swap of habitat. While the outcome for wetland mitigation may not be an ‘unmitigated disaster’ it is, at best, apparently only modestly successful.

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.

Macroinvertebrates have been widely used in freshwater ecosystems as surrogates to assess the impacts of waste discharges and water pollution. However, often interpretations have been made on the impact of one pollutant in the presence of others that may provide an unidentified additive effective or otherwise confound the results. There have been few opportunities to study the impact of pollutants without such potentially confounding effects. We studied macroinvertebrates using a replicated kick sampling technique and identified to the family level to assess and compare the effects of zinc-rich coal-mine waste and organic pollution from treated sewage on an otherwise clean upland stream network within a world heritage area. We used multivariate analysis of macroinvertebrate assemblages from polluted and clean sites to measure and compare the effect of each waste impact to community structure. We also calculated three widely used biotic indices (Ephemeroptera, Plecoptera and Trichoptera (EPT) family richness, family richness, and abundance) and found that the EPT index was the only one to respond to both pollution types. Macroinvertebrate abundance was an important attribute of the study, with each source of pollution having a contrasting effect on total abundance. It also helped us to measure the relative response of families to each pollutant. There was an initial significant modification of macroinvertebrate assemblages below the outflow of each of the pollutants, followed by different degrees of recovery downstream.

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.

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.

Action on issues of ecological significance often requires changes in personal behaviour and political consensus on technologies to support these changes. Unfortunately, many consultation processes only engage a narrow range of stakeholders, usually those professionally engaged or already active on a range of community issues. This paper illustrates how people who are ‘hard to reach’ or seen as ‘apathetic’ might be engaged using ‘action-conversations’ that explore the social climate for action and how scientific/technical messages can be framed in the language of the community.

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.

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.