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The term ‘biodiversity’ emerged in the mid-1980s and quickly became sufficiently popular that it could have been viewed as a ‘new field of science’. The broader community has also embraced the term and, ultimately, it has become a proxy for species conservation. As a consequence, conservation of biodiversity has effectively become the only approach to minimising continued species loss. However, despite the widespread use of the term, there is confusion over its definition, even among disciplines to which the term has become a focus. In Australia, much of the biodiversity conservation/restoration is community-driven (e.g., landcare, political pressure of animal welfare groups) with a focus on species and habitat biodiversity. Genetic diversity is seldom seriously considered. As a consequence, native species biodiversity management is often not maximising the potential outcomes. Arguably the greatest issue associated with incorporating genetics more centrally into biodiversity restoration is that i...

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.

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...

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.

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.

Historically, most people have tended to visit national parks for ‘rest, relaxation and reinvigoration’, typically resulting in moderate ecological impacts. However, increasingly, recreation in natural areas is including ‘adventure’ sports. One such recreation/sport that now incorporates a range of forms, including adventure derivatives, is mountain biking. In the more extreme forms, riders use extensive trials, often with steep segments and natural or human-made obstacles demonstrate technical skills (e.g., balance, calculated risk-taking, excitement, speed). Appreciation of the natural environment is seldom, if ever, a reason for participation. In this paper we consider the potential for impact on the fauna of national parks. While there is a dearth of information on the impact of mountain biking, we conclude that park management needs to be strategic in their consideration of the issues associated with mountain biking or the outcome will be further degradation of natural areas and, at the least, loss of many animals if not major threats to populations.

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.

The New South Wales Threatened Species Conservation Amendment (Biodiversity Banking) Bill 2006 was implemented to formalise the concept of biodiversity offsets. Its underpinning focus is to allow development in rapidly urbanising areas of the Sydney region and the coastal ribbon of New South Wales. Under defined circumstances biodiversity impacts due to urban development may be offset elsewhere, often in rural areas, where equivalent biodiversity values are identified. This legislation was modelled on the United States of America (US) wetland mitigation banking approach. I investigated some of the pitfalls of the US experience that should have been considered in the implementation of the New South Wales legislation and conclude that most issues appear to be associated with the narrowness of concepts around biodiversity, deficiencies in compliance, and long term monitoring and management of the offset ecosystems.

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.

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.

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.

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.

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 ...

The functional significance of allometric change in reptiles has received limited attention and the reason for such changes has been regarded as ‘obscure’. In this paper we report data on the Australian Pogona barbata , the eastern bearded dragon, from across their range and review changes in allometric growth among juveniles, and adult males and females and consider the functional relevance of these changes. There were significant differences in the population for mass, tail length, tail width, rear leg length and jaw length. These differences were consistent with differences required in locomotor performance and thus habitat use, together with access to different preferred dietary components.

Differences may occur in the carnivore–omnivore–herbivore spectrum over the lifespan of a reptilian species, but it seldom occurs between adult males and females. Information regarding the dietary habits of Australian eastern bearded dragon (Pogona barbata) is also limited. We dissected museum specimens and road kills of the Australian eastern bearded dragon to compare ontogenetic shift in diet. Juveniles were insectivorous. They typically consumed larger, more active, arthropod prey than mature individuals – they are active predators. Adults were omnivorous and typically consumed small arthropod prey, and tended to be sit-and-wait predators. Mature males, particularly larger males, were primarily herbivorous. Such divergence in adult reptilian diet has rarely been reported. We suggest that the dietary switches observed are consistent with the Optimum Foraging Model. Juveniles require a high protein diet to maximise growth from juvenile to maturity. Beyond maturity females continue to require higher levels of protein for reproduction than males. At least in part, this is because males rely on sham aggression to defend territory during the reproductive season rather than resorting to aggressive behaviour. This results in a lesser requirement for protein for adult males than is required for juveniles and adult females. Males have the advantage of not being as dependent on protein, and thus are able to rely more heavily on vegetation.

PRESSEY, R. L. AND NICHOLLS, A. 0., 1989b. Efficiency in conservation evaluation: scoring vs. iterative approaches. Biol. Conserv. 50: 199-218. PRESSEY, R. L. AND NICHOLLS, A. 0., in press. Reseive selection in the Western Division of New South Wales: development of a new procedure based on land system mapping. In: Cost-effective Survey Methods for Nature Conservation ed by C. R. Margules and M. P. Austin. CSIRO/ NPWS.

The phylogenetic relationships of the Australian scincid lizards currently assigned to the genus Leiolopisma have been examined by quantitative micro-complement fixation (MC'F) comparisons of serum albumin. The results of these comparisons do not support the monophyly implicit in these species' current congeneric status, but suggest instead that the Australian species of Leiolopisma belong to several distinct phyletic lineages within the Eugongylus group. These findings are supported by several sets of non-biochemical characters, including features of scalation, osteology and karyotype. None of the Australian species shares a close relationship with the type-species of Leiolopisrna (L. telfairii), and so a new taxonomic arrangement is proposed which distributes them among the following genera: Bartleia, gen. nov. (jigurru); Bassiana, gen. nov. (duperreyi, platynotum and trilineata); Cautula, gen. nov. (zia); Niveoscincus, gen. nov. (coventryi, greeni, metallicus, microlepidotus, ocellatus, orocryptus, palfreymani and pretiosus); and Pseudemoia Fuhn, 1967 (baudini, entrecasteauxii Group 1; entrecasteauxii Group 2, rawlinsoni and spenceri). Preliminary comparisons suggest that other Leiolopisma species, from New Caledonia, Lord Howe I. and New Zealand, belong to phyletic lineages which are distinct from any of the Australian 'Leiolopisma' and from the type-species.