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Urban greenspaces harbor considerable biodiversity. Such areas include spontaneously vegetated spaces such as such as brownfields, street or railway verges and vacant lots. While these spaces may contribute to urban conservation, their informal and liminal nature poses a challenge for reviewing what we know about their value for biodiversity. The relevant literature lacks a common terminology. This paper applied a formal definition and typology of informal urban greenspace (IGS) to identify and systematically review a total of 174 peer-reviewed papers in English (152), German (14) and Japanese (8). We identified three main topics: value for conservation (94 papers), factors influencing diversity (80), and non-indigenous species (37). Additionally, we analyzed this literature for temporal trends, spatial patterns, studied IGS types, taxa, climate zones, human impact types, and key authors. Results show IGS plays an important role for biodiversity. Management practices were identified as the most common and negative impact on diversity, while vegetation, site age, distance to city center, and habitat diversity were positive-influence factors. The number and impact of non-indigenous species varied widely. The analysis of literature patterns reveals: an increase in publications over the last 15 years and a strong geographic bias in publications, as well as toward temperate and humid climate zones. Studies of gap, powerline and microsite IGS were scarce, as were studies of mammals and reptiles. Results suggest different maintenance regimes for IGS may improve its contribution to urban conservation. We therefore propose adapting management to the local context. [ABSTRACT FROM AUTHOR]

Abstract: Extreme environmental temperature could impact the physiology and ecology of animals. The stress endocrine axis provides necessary physiological stress response to acute (day–day) stressors. Presently, there are no empirical evidences showing that exposure to extreme thermal stressor could cause chronic stress in amphibians. This could also modulate the physiological endocrine sensitivity to acute stressors and have serious implications for stress coping in amphibians, particularly those living in fragmented and disease prone environments. We addressed this important question using the cane toad (Rhinella marina) model from its introduced range in Queensland, Australia. We quantified their physiological endocrine sensitivity to a standard acute (capture and handling) stressor after exposing the cane toads to thermal shock at 35°C for 30min daily for 34 days. Corticosterone (CORT) responses to the capture and handling protocol were measured on three sampling intervals (days 14, 24, and 34) to determine whether the physiological endocrine sensitivity was maintained or modulated over-time. Two control groups (C1 for baseline CORT measurement only and C2 acute handled only) and two temperature treatment groups (T1 received daily thermal shock up to day 14 only and a recovery phase of 20 days and T2 received thermal shock daily for 34 days). Results showed that baseline CORT levels remained high on day 14 (combined effect of capture, captivity and thermal stress) for both T1 and T2. Furthermore, baseline CORT levels decreased for T1 once the thermal shock was removed after day 14 and returned to baseline by day 29. On the contrary, baseline CORT levels kept on increasing for T2 over the 34 days of daily thermal shocks. Furthermore, the magnitudes of the acute CORT responses or physiological endocrine sensitivity were consistently high for both C1 and T1. However, acute CORT responses for T2 toads were dramatically reduced between days 24 and 34. These novel findings suggest that repeated exposure to extreme thermal stressor could cause chronic stress and consequently suppress the physiological endocrine sensitivity to acute stressors (e.g. pathogenic diseases) in amphibians. [Copyright &y& Elsevier]

Habitat remnants on urban green-space areas (i. E. Parks, gardens and golf courses) sometimes provide refuge to urban-avoiding wildlife, leading some to suggest these areas may play a role in wildlife conservation if they are appropriately designed and managed. The high densities observed on some green-space areas may however be attributed to external influences. Localised efforts to enhance the habitat value of urban green-space areas may therefore have little more than a cosmetic effect. This study investigated environmental factors influencing bird, reptile, mammal and amphibian diversity on Australian golf courses to assess the efficacy of small-scale conservation efforts. Abundance and species richness did not simply reflect local habitat qualities but were instead, partly determined by the nature of the surrounding landscape (i. E. The area of adjacent built land, native vegetation and the number of connecting streams). Vertebrate abundance and species richness were however, also associated with on-site habitat characteristics, increasing with the area of native vegetation (all vertebrates), foliage height diversity and native grass cover (birds), tree density, native grass cover and the number of hollows (mammals), woody debris, patch width and canopy cover (reptiles), waterbody heterogeneity and aquatic vegetation complexity (frogs). Localised conservation efforts on small land types can benefit urban-avoiding wildlife. Urban green-space areas can provide refuge to urban-avoiding vertebrates provided combined efforts are made at patch (management), local (design) and landscape (planning) scales. [Copyright &y& Elsevier]

Constructed ponds are an important consideration in the conservation of wetland biota in agricultural landscapes. Twenty-two natural ponds and 22 adjacent constructed ponds (farm dams) were surveyed on the Southern Tablelands of New South Wales to compare patterns of use by frogs and develop frog conservation recommendations. Farm dams supported similar numbers of frog species to natural ponds, although differences in frog assemblage were observed between the pond types. Limnodynastes tasmaniensis and Uperolia laevigata were significantly more likely to occur at farm dams while L. peronii was more likely to occur at natural ponds. Results suggest waterbodies with high levels of emergent vegetation cover that lack fish are likely to support a high number of frog species, regardless of origin (i.e. natural or constructed). However, it is important for landholders to conserve natural waterbodies as these environments appear likely to support frog species that do not use farm dams. [Copyright &y& Elsevier]

It is well known that the disease chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis ( Bd ) has contributed to amphibian declines worldwide. The impact of Bd varies, with some species being more susceptible to infection than others. Recent evidence has shown that Bd can have sub-lethal effects, whereby increases in stress hormones have been associated with infection. Could this increased stress response, which is a physiological adaptation that provides an increased resilience against Bd infection, potentially be a trade-off with important life-history traits such as reproduction? We studied this question in adult male frogs of a non-declining species ( Litoria wilcoxii ). Frogs were sampled for (1) seasonal hormone (testosterone and corticosterone), color and disease profiles, (2) the relationship between disease infection status and hormone levels or dorsal color, (3) subclinical effects of Bd by investigating disease load and hormone level, and (4) reproductive and stress hormone relationships independent of disease. Testosterone levels and color score varied seasonally (throughout the spring/summer months) while corticosterone levels remained stable. Frogs with high Bd prevalence had significantly higher corticosterone levels and lower testosterone levels compared to uninfected frogs, and no differences in color were observed. There was a significant positive correlation between disease load and corticosterone levels, and a significant negative relationship between disease load and testosterone. Our field data provides novel evidence that increased physiological stress response associated with Bd infection in wild frogs, could suppress reproduction by down-regulating gonadal hormones in amphibians, however the impacts on reproductive output is yet to be established. [ABSTRACT FROM AUTHOR]

Abstract: Repeatability of physiological response variables, such as the stress hormone corticosterone, across numerous sampling occasions is an important assumption for their use as predictors of behaviour, reproduction and fitness in animals. Very few studies have actually tested this assumption in free-living animals under uncontrolled natural conditions. Non-invasive urine sampling and standard capture handling protocol have enabled the rapid quantification of baseline corticosterone and short-term corticosterone stress responses in anuran amphibians. In this study, established non-invasive methods were used to monitor physiological stress and urinary testosterone levels in male individuals of the terrestrial breeding Fijian ground frog (Platymantis vitiana). Adult male frogs (n=20) were sampled at nighttime on three repeated occasions at intervals of 14days during their annual breeding season on Viwa Island, Fiji. All frogs expressed urinary corticosterone metabolite responses to the capture and handling stressor, with some frogs showing consistently higher urinary corticosterone responses than others. Ranks of corticosterone values at 0, 4 and 8h, and the corrected rank were highly significant (r =0.75–0.99) between the three repeated sampling occasions. Statistical repeatabilities were high for baseline corticosterone (r =0.973) and for corticosterone values at 2h (r =0.862), 4h (r =0.861), 6h (r =0.820) and 8h (r =0.926), and also for the total (inclusive of baseline corticosterone values) and the corrected integrated responses (index of the acute response) [r =0.867 and r =0.870]. Urinary testosterone levels also showed high statistical repeatability (r =0.78). Furthermore, variation in baseline and short-term corticosterone stress responses was greater between individuals than within individuals. Baseline urinary corticosterone was significantly negatively correlated with the corrected integrated corticosterone response (r =−0.3, p <0.001) but non-significantly with body-condition (r =−0.04) and baseline urinary testosterone (r =−0.07). In contrast, the corrected integrated corticosterone response was positively correlated (non-significantly) with baseline urinary testosterone (r =+0.04) and body-condition (r =+0.08). Urinary testosterone levels and body-condition were significantly negatively correlated (r =−0.23, p <0.001). The results suggest that male frogs with higher levels of testosterone could have depleted energy reserve during the breeding period. The acute corticosterone responses help in replenishing energy that is needed for breeding and survival. The results also provide some support to the ‘cort-fitness’ hypothesis as highlighted by the negative correlation between baseline corticosterone and body-condition. It is most likely that the acute corticosterone response is adaptive and linked positively with reproductive fitness and survival in male anurans. [Copyright &y& Elsevier]

Abstract: Amphibians respond to environmental stressors by secreting corticosterone, a stress hormone which promotes physiological and behavioral responses. Capture handling can be used to stimulate physiological stress response in amphibians. The use of single blood sampling and presentation of mean data often limits the quantification of within and between individual variation in baseline and short-term corticosterone stress responses in amphibians. It is important for studies of amphibian physiological ecology to determine whether baseline and short-term corticosterone stress responses are consistent or not. We quantified repeatability (r), a statistical measure of consistency, in baseline and short-term corticosterone stress responses to a standard capture and handling stress protocol in free-living adult male cane toads (Rhinella marina). Corticosterone metabolite concentrations were measured entirely non-invasively in male toad urine samples via an enzyme-immunoassay. During the first sampling occasion, urine samples were collected manually from individual male toads (n=20) immediately upon field capture. Toads were handled for 5min then transferred to plastic bags (constituting a mild stressor), and urine samples were collected hourly over 8h in the field. The toads were resampled for baseline (0h) urine corticosterone with hourly urine sampling over 8h (for quantification of the stress induced corticosterone) at 14day intervals on three consecutive occasions. Within and between sample variations in urinary corticosterone metabolite concentrations were also quantified. All toads expressed a corticosterone stress response over 8h to our standard capture and handling stress protocol. Variations both within and between toads was higher for corrected integrated corticosterone concentrations than corticosterone concentrations at baseline, 3 or 6h. Baseline urinary corticosterone metabolite concentration of the male toads was highly repeatable (r =0.877) together with high statistical repeatabilities for 3h (r =0.695), 6h (r =0.428) and 8h (r =0.775) corticosterone metabolite concentrations, and for the total and corrected integrated corticosterone responses (r =0.807; r =0.743 respectively). This study highlights that baseline and short-term corticosterone stress responses are repeatable in free-living amphibians. Future studies should utilize this non-invasive tool to explore repeatability among seasons and across years, and determine its functional significance in relation to behavioral ecology and reproduction in amphibians generally. [Copyright &y& Elsevier]

Abstract: The emerging amphibian disease chytridiomycosis, which is caused by the fungal pathogen (Batrachochytrium dendrobatidis, Bd), has caused mass mortalities of native amphibian populations globally. There have been no previous studies on the relationships between stress hormones in free-living amphibians and Bd infections. In this study, we measured urinary corticosterone metabolite concentrations and Bd infections within free-living populations of male Stony Creek frog (Litoria wilcoxii) in Queensland, Australia. Prevalence of Bd zoospores from frog skin swabs was quantified using a real-time quantitative PCR technique. A urinary corticosterone enzyme-immunoassay (EIA) was validated using adrenocorticotropic hormone (ACTH) challenge. Urinary corticosterone concentrations of male frogs increased within 1–2days after ACTH challenge and returned to baseline levels within 3days post-ACTH injection. None of the frogs showed any rise in urinary corticosterone after saline injections. Individual male frogs showed either low or high baseline corticosterone concentrations. Male frogs identified as positive for Bd infection had significantly higher baseline urinary corticosterone concentrations in comparison to Bd negative male frogs. Urinary corticosterone EIA provides a reliable indication of stress in this frog species and this non-invasive physiological tool can be used to further assess the dynamics of Bd infections and physiological stress responses in other native amphibians. [Copyright &y& Elsevier]

Abstract: Global average surface temperatures have increased rapidly over the last 100 years and there is accumulating evidence that climate change is already causing shifts in species’ distributions. We use extensive abundance data and expected range shifts across altitudinal gradients to predict changes in total population size of rainforest birds of Australian tropical rainforests in response to climate warming. According to our most conservative model scenario, 74% of rainforest birds of north-eastern Australia are predicted to become threatened (including 26 critically endangered species) as a result of projected mid-range warming expected within the next 100 years. Extinction risk varies according to where along the altitudinal gradient a species is currently most abundant. Upland birds are most affected and are likely to be immediately threatened by even small increases in temperature. In contrast, there is a capacity for the population size of lowland species to increase, at least in the short term. We conclude that abundance data collected across climatic gradients will be fundamental to gaining an understanding of population size change associated with climate warming. [Copyright &y& Elsevier]

Determining the role of an infectious agent in contributing to wildlife population declines is a pervasive problem in the field of conservation biology. We expand on a recently proposed broad investigative approach for disease, with a systematic framework outlining the specific types of individual- and population-scale empirical evidence required to demonstrate whether a pathogen is a component cause of declines in wild animal populations. Using koala ( Phascolarctos cinereus ) population declines and their putative association with the bacterial disease chlamydiosis (Family Chlamydiaceae ) as a case study, we review the relevant published literature and synthesize a logical conceptual argument based on our suggested framework. Available empirical evidence supports a role for chlamydiosis contributing to host mortality and sterility, and cannot rule out a role of chlamydiosis as a component cause of koala population declines. However, the relative importance of chlamydiosis (among other threatening processes) as a driver of changes in koala demography and autecology may differ depending on the particular population or system examined, and this has yet to be elucidated over the koala's distributional range. Our approach allows us to highlight current research gaps in order to assist with future policy planning and conservation strategy. We recommend that a similar approach will assist in the evaluation of the role of disease in population declines in other ecological systems. [ABSTRACT FROM AUTHOR]

Infectious diseases can be key threatening processes for biodiversity conservation. However, establishing the relative importance of disease (among other threatening processes) as a driver of species declines can be challenging. Bias in the directions that a research field may take as it develops – due to factors such as conservation policy, funding, public perception, and available expertise and technology – may exacerbate this difficulty. Chlamydiosis (infection with bacteria in Family Chlamydiaceae ) is an example of an infectious disease with a poorly understood role in koala ( Phascolarctos cinereus ) population dynamics. The arboreal folivorous koala is an internationally recognized iconic species of high conservation, sociocultural and economic value. To date, no studies have quantitatively examined the breadth and scope of research related to koala chlamydiosis, nor systematically identified the current research gaps. We systematically and quantitatively reviewed a comprehensive database of literature related to koala chlamydiosis, classified and examined the main foci of the research, and evaluated research gaps with the goal of assisting policy planning for funding further koala chlamydiosis research. We examined published literature with regard to journal category, authorship, funding, spatiotemporal scope, study foci and type, chlamydial species examined, methodological design and overall findings. Among the 117 peer-reviewed papers published between 1970 and 2016 that fit our criteria, the most striking finding was the relative lack of population-level disease studies within the last two decades to examine mechanisms of chlamydial infection dynamics. This research gap is of particular concern given the potential role of Chlamydia in koala population declines, and the recent dramatic changes in our understanding of pathogen phylogeny and improved diagnostic approaches. Our results demonstrate a pressing need for future in situ comprehensive longitudinal population-level studies from diverse geographic regions. These studies must utilize up-to-date diagnostic methods capable of distinguishing chlamydial species and strains to elucidate the role of chlamydial infection in koala population declines and the underlying mechanisms involved. They should also employ rigorous epidemiological methodologies and evaluate co-infection, habitat, climatic and demographic data. Our findings suggest some key research gaps concerning koala chlamydiosis, and are hence important for guiding future research into koala chlamydiosis and conservation. [ABSTRACT FROM AUTHOR]

Ecosystem monitoring networks aim to collect data on physical, chemical and biological systems and their interactions that shape the biosphere. Here we introduce the Australian SuperSite Network that, along with complementary facilities of Australia's Terrestrial Ecosystem Research Network (TERN), delivers field infrastructure and diverse, ecosystem-related datasets for use by researchers, educators and policy makers. The SuperSite Network uses infrastructure replicated across research sites in different biomes, to allow comparisons across ecosystems and improve scalability of findings to regional, continental and global scales. This conforms with the approaches of other ecosystem monitoring networks such as Critical Zone Observatories, the U.S. National Ecological Observatory Network; Analysis and Experimentation on Ecosystems, Europe; Chinese Ecosystem Research Network; International Long Term Ecological Research network and the United States Long Term Ecological Research Network. The Australian SuperSite Network currently involves 10 SuperSites across a diverse range of biomes, including tropical rainforest, grassland and savanna; wet and dry sclerophyll forest and woodland; and semi-arid grassland, woodland and savanna. The focus of the SuperSite Network is on using vegetation, faunal and biophysical monitoring to develop a process-based understanding of ecosystem function and change in Australian biomes; and to link this with data streams provided by the series of flux towers across the network. The Australian SuperSite Network is also intended to support a range of auxiliary researchers who contribute to the growing body of knowledge within and across the SuperSite Network, public outreach and education to promote environmental awareness and the role of ecosystem monitoring in the management of Australian environments. [ABSTRACT FROM AUTHOR]

Abstract: Rapid colour changes in vertebrates have fascinated biologists for centuries, herein we demonstrate dynamic colour change in an anuran amphibian, the stony creek frog (Litoria wilcoxii), which turns from brown to bright (lemon) yellow during amplexus. We show this by comparing the colour of baseline (unpaired males) and amplecting (paired) males. We also investigate the possible role of stress and stress hormones on this colour change. Frogs were subjected to four different levels of stressors (handling, toe-clipping, saline injection and adrenocorticotropic hormone [ACTH] injection) and the colour change was measured using digital photography. A comparison of baseline colour and stress hormone (corticosterone) levels was also conducted to give further insight to this topic. From the images, the Red Blue Green (RGB) colour values were calculated, and a principal components analysis (PCA) was used to create a single colour metric (the major axis) as an index of colour in the visible spectrum. A moderate stressor (toe-clipping) led to a significant change in colour (within 10min) similar to that of amplecting males. Surprisingly, neither a mild stressor (handling and saline injection) nor the maximum stressor (handling and ACTH injection) led to a lightening response. This study confirms that the dynamic male colour change in this species in response to medium stressors adds new knowledge to the understanding of the functional mechanisms of dynamic colour change in amphibians. [Copyright &y& Elsevier]

Abstract: We identify the 10 major terrestrial and marine ecosystems in Australia most vulnerable to tipping points, in which modest environmental changes can cause disproportionately large changes in ecosystem properties. To accomplish this we independently surveyed the coauthors of this paper to produce a list of candidate ecosystems, and then refined this list during a 2-day workshop. The list includes (1) elevationally restricted mountain ecosystems, (2) tropical savannas, (3) coastal floodplains and wetlands, (4) coral reefs, (5) drier rainforests, (6) wetlands and floodplains in the Murray-Darling Basin, (7) the Mediterranean ecosystems of southwestern Australia, (8) offshore islands, (9) temperate eucalypt forests, and (10) salt marshes and mangroves. Some of these ecosystems are vulnerable to widespread phase-changes that could fundamentally alter ecosystem properties such as habitat structure, species composition, fire regimes, or carbon storage. Others appear susceptible to major changes across only part of their geographic range, whereas yet others are susceptible to a large-scale decline of key biotic components, such as small mammals or stream-dwelling amphibians. For each ecosystem we consider the intrinsic features and external drivers that render it susceptible to tipping points, and identify subtypes of the ecosystem that we deem to be especially vulnerable. [Copyright &y& Elsevier]