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Tephritid fruit flies are among the most destructive horticultural pests posing risks to Australia's multi-billion-dollar horticulture industry. Currently, there are 11 pest fruit fly species of economic concern in Australia. Of these, nine are native to this continent (Bactrocera aquilonis, B. bryoniae, B. halfordiae, B. jarvisi, B. kraussi, B. musae, B. neohumeralis, B. tryoni and Zeugodacus cucumis), while B. frauenfeldi and Ceratitis capitata are introduced. To varying degrees these species are costly to Australia's horticulture through in-farm management, monitoring to demonstrate pest freedom, quarantine and trade restrictions, and crop losses. Here, we used a common species distribution model, Maxent, to assess climate suitability for these 11 species under baseline (1960-1990) and future climate scenarios for Australia. Projections indicate that the Wet Tropics is likely to be vulnerable to all 11 species until at least 2070, with the east coast of Australia also likely to remain vulnerable to multiple species. While the Cape York Peninsula and Northern Territory are projected to have suitable climate for numerous species, extrapolation to novel climates in these areas decreases confidence in model projections. The climate suitability of major horticulture areas currently in eastern Queensland, southern-central New South Wales and southern Victoria to these pests may increase as climate changes. By highlighting areas at risk of pest range expansion in the future our study may guide Australia's horticulture industry in developing effective monitoring and management strategies.

The ability of species to track their climate niche is dependent on their dispersal potential and the connectivity of the landscape matrix linking current and future suitable habitat. However, studies modeling climate-driven range shifts rarely address the movement of species across landscapes realistically, often assuming "unlimited" or "no" dispersal. Here, we incorporate dispersal rate and landscape connectivity with a species distribution model (Maxent) to assess the extent to which the Cunningham's skink (Egernia cunninghami) may be capable of tracking spatial shifts in suitable habitat as climate changes. Our model was projected onto four contrasting, but equally plausible, scenarios describing futures that are (relative to now) hot/wet, warm/dry, hot/with similar precipitation and warm/wet, at six time horizons with decadal intervals (2020-2070) and at two spatial resolutions: 1 km and 250 m. The size of suitable habitat was projected to decline 23-63% at 1 km and 26-64% at 250 m, by 2070. Combining Maxent output with the dispersal rate of the species and connectivity of the intervening landscape matrix showed that most current populations in regions projected to become unsuitable in the medium to long term, will be unable to shift the distance necessary to reach suitable habitat. In particular, numerous populations currently inhabiting the trailing edge of the species' range are highly unlikely to be able to disperse fast enough to track climate change. Unless these populations are capable of adaptation they are likely to be extirpated. We note, however, that the core of the species distribution remains suitable across the broad spectrum of climate scenarios considered. Our findings highlight challenges faced by philopatric species and the importance of adaptation for the persistence of peripheral populations under climate change.

Current evidence of phenological responses to recent climate change is substantially biased towards northern hemisphere temperate regions. Given regional differences in climate change, shifts in phenology will not be uniform across the globe, and conclusions drawn from temperate systems in the northern hemisphere might not be applicable to other regions on the planet. We conduct the largest meta-analysis to date of phenological drivers and trends among southern hemisphere species, assessing 1208 long-term datasets from 89 studies on 347 species. Data were mostly from Australasia (Australia and New Zealand), South America and the Antarctic/subantarctic, and focused primarily on plants and birds. This meta-analysis shows an advance in the timing of spring events (with a strong Australian data bias), although substantial differences in trends were apparent among taxonomic groups and regions. When only statistically significant trends were considered, 82% of terrestrial datasets and 42% of marine datasets demonstrated an advance in phenology. Temperature was most frequently identified as the primary driver of phenological changes; however, in many studies it was the only climate variable considered. When precipitation was examined, it often played a key role but, in contrast with temperature, the direction of phenological shifts in response to precipitation variation was difficult to predict a priori. We discuss how phenological information can inform the adaptive capacity of species, their resilience, and constraints on autonomous adaptation. We also highlight serious weaknesses in past and current data collection and analyses at large regional scales (with very few studies in the tropics or from Africa) and dramatic taxonomic biases. If accurate predictions regarding the general effects of climate change on the biology of organisms are to be made, data collection policies focussing on targeting data-deficient regions and taxa need to be financially and logistically supported.

The conservation efficiency of Protected Areas (PA) is influenced by the health and characteristics of the surrounding landscape matrix. Fragmentation of adjacent lands interrupts ecological flows within PAs and will decrease the ability of species to shift their distribution as climate changes. For five periods across the 21(st) century, we assessed changes to the extent of primary land, secondary land, pasture and crop land projected to occur within 50 km buffers surrounding IUCN-designated PAs. Four scenarios of land-use were obtained from the Land-Use Harmonization Project, developed for the Intergovernmental Panel on Climate Change's Fifth Assessment Report (AR5). The scenarios project the continued decline of primary lands within buffers surrounding PAs. Substantial losses are projected to occur across buffer regions in the tropical forest biomes of Indo-Malayan and the Temperate Broadleaf forests of the Nearctic. A number of buffer regions are projected to have negligible primary land remaining by 2100, including those in the Afrotropic's Tropical/Subtropical Grassland/Savanna/Shrubland. From 2010-2050, secondary land is projected to increase within most buffer regions, although, as with pasture and crops within tropical and temperate forests, projections from the four land-use scenarios may diverge substantially in magnitude and direction of change. These scenarios demonstrate a range of alternate futures, and show that although effective mitigation strategies may reduce pressure on land surrounding PAs, these areas will contain an increasingly heterogeneous matrix of primary and human-modified landscapes. Successful management of buffer regions will be imperative to ensure effectiveness of PAs and to facilitate climate-induced shifts in species ranges.

Conservation actions focused on flagship species are effective at raising funds and awareness. Here, McGowan et al. show that prioritizing areas for conservation based on the presence of flagship species results in the selection of areas with ~ 79-89% of the total species that would be selected by maximizing biodiversity representation only.

Societal Impact Statement Urban forests are recognized for the multiple benefits they provide to city‐dwellers. However, climate change will affect tree species survival and persistence in urban ecosystems. Tree failures will cause economic losses and jeopardize the delivery of societal benefits. The impacts of climate change will depend on the species’ resilience and adaptive capacity, as well as management actions which may ameliorate some of the negative impacts. Here, we assessed the potential vulnerability of Australia's urban forests to climate extremes. Our results can be used for future urban planning aiming to incorporate species that are well‐adapted to the hotter, drier climates expected with climate change. Summary Urban forests (UFs) are recognized for the multiple benefits they provide to city‐dwellers. However, global climate change—particularly predicted increases in the frequency and intensity of heatwaves and drought—will affect tree species’ performance and survival in urban ecosystems. Here, we assessed species composition and potential vulnerability of UFs in 22 Australian significant urban areas (SUAs) to heat and/or moisture stress. We quantified species’ realized climatic niches across their known distribution, and assessed the extent to which baseline climate in the SUAs where a particular species is planted fell within its niche. We used three environmental variables to group species based on their potential climate vulnerability. UFs varied in species composition and climate vulnerability across the continent. In general, neither climate similarity nor geographical proximity were good predictors of species composition among UFs. Of 1,342 tree species assessed (68.4% natives), 53% were considered potentially vulnerable to heat and/or moisture stress in at least one city where they are currently planted. Our results highlight the climate vulnerability of current plantings across Australian SUAs and can be used to direct future species selection that considers the species’ climate of origin and climatic niche. UF planning can incorporate species from SUAs with similar climates and with low vulnerability to contemporary, as well as future climate conditions. Species with high climate vulnerability, in contrast, may require more intensive management to avoid failure under future hotter, drier climate conditions.

Abstract Climate change vulnerability assessment (CCVA) has become a mainstay conservation decision support tool. CCVAs are recommended to incorporate three elements of vulnerability – exposure, sensitivity and adaptive capacity – yet, lack of data frequently leads to the latter being excluded. Further, weighted or unweighted scoring schemes, based on expert opinion, may be applied. Comparisons of these approaches are rare. In a CCVA for 17 Australian lizard species, we show that membership within three vulnerability categories (low, medium and high) generally remained similar regardless of the framework or scoring scheme. There was one exception however, where, under the warm/dry scenario for 2070, including adaptive capacity lead to five fewer species being classified as highly vulnerable. Two species, Eulamprus leuraensis and E. kosciuskoi, were consistently ranked the most vulnerable, primarily due to projected losses in climatically suitable habitat, narrow thermal tolerance and specialist habitat requirements. Our findings provide relevant information for prioritizing target species for conservation and choosing appropriate conservation actions. We conclude that for the species included in this study, the framework and scoring scheme used had little impact on the identification of the most vulnerable species. We caution, however, that this outcome may not apply to other taxa or regions.

Abstract Establishing corridors of connecting habitat has become a mainstay conservation strategy to maintain gene flow and facilitate climate‐driven range shifts. Yet, little attention has been given to ascertaining the extent to which corridors will benefit philopatric species, which might exhibit localized adaptation. Measures of genetic connectivity and adaptive genetic variation across species’ ranges can help fill this knowledge gap. Here, we characterized the spatial genetic structure of Cunningham's skink (Egernia cunninghami), a philopatric species distributed along Australia's Great Dividing Range, and assessed evidence of localized adaptation. Analysis of 4,274 SNPs from 94 individuals sampled at four localities spanning 500 km and 4° of latitude revealed strong genetic structuring at neutral loci (mean FST ± SD = 0.603 ± 0.237) among the localities. Putatively neutral SNPs and those under divergent selection yielded contrasting spatial patterns, with the latter identifying two genetically distinct clusters. Given low genetic connectivity of the four localities, we suggest that the natural movement rate of this species is insufficient to keep pace with spatial shifts to its climate envelope, irrespective of habitat availability. In addition, our finding of localized adaptation highlights the risk of outbreeding depression should the translocation of individuals be adopted as a conservation management strategy.

Giardia and Cryptosporidium are amongst the most common protozoan parasites identified as causing enteric disease in pinnipeds. A number of Giardia assemblages and Cryptosporidium species and genotypes are common in humans and terrestrial mammals and have also been identified in marine mammals. To investigate the occurrence of these parasites in an endangered marine mammal, the Australian sea lion (Neophoca cinerea), genomic DNA was extracted from faecal samples collected from wild populations (n = 271) in Southern and Western Australia and three Australian captive populations (n = 19). These were screened using PCR targeting the 18S rRNA of Giardia and Cryptosporidium. Giardia duodenalis was detected in 28 wild sea lions and in seven captive individuals. Successful sequencing of the 18S rRNA gene assigned 27 Giardia isolates to assemblage B and one to assemblage A, both assemblages commonly found in humans. Subsequent screening at the gdh and β-giardin loci resulted in amplification of only one of the 35 18S rRNA positive samples at the β-giardin locus. Sequencing at the β-giardin locus assigned the assemblage B 18S rRNA confirmed isolate to assemblage AI. The geographic distribution of sea lion populations sampled in relation to human settlements indicated that Giardia presence in sea lions was highest in populations less than 25 km from humans. Cryptosporidium was not detected by PCR screening in either wild colonies or captive sea lion populations. These data suggest that the presence of G. duodenalis in the endangered Australian sea lion is likely the result of dispersal from human sources. Multilocus molecular analyses are essential for the determination of G. duodenalis assemblages and subsequent inferences on transmission routes to endangered marine mammal populations.

Background Shrubs play a key role in biogeochemical cycles, prevent soil and water erosion, provide forage for livestock, and are a source of food, wood and non-wood products. However, despite their ecological and societal importance, the influence of different environmental variables on shrub distributions remains unclear. We evaluated the influence of climate and soil characteristics, and whether including soil variables improved the performance of a species distribution model (SDM), Maxent. Methods This study assessed variation in predictions of environmental suitability for 29 Australian shrub species (representing dominant members of six shrubland classes) due to the use of alternative sets of predictor variables. Models were calibrated with (1) climate variables only, (2) climate and soil variables, and (3) soil variables only. Results The predictive power of SDMs differed substantially across species, but generally models calibrated with both climate and soil data performed better than those calibrated only with climate variables. Models calibrated solely with soil variables were the least accurate. We found regional differences in potential shrub species richness across Australia due to the use of different sets of variables. Conclusions Our study provides evidence that predicted patterns of species richness may be sensitive to the choice of predictor set when multiple, plausible alternatives exist, and demonstrates the importance of considering soil properties when modeling availability of habitat for plants.