Search Results (332)

Temperate Highland Peat Swamps on Sandstone (THPSS) are wetlands in the Blue Mountains, south-eastern Australia. The wetlands have legislative protection as endangered ecological communities. They have long-standing cultural significance for Gundungurra Traditional Custodians. Previous studies document their degradation by urban development and vulnerability to extreme weather. Water quality in our study was assessed at wetlands in protected areas and compared with others exposed to urban development. We derived water quality guidelines that are intended to help future water quality assessment at THPSS and, in particular, to detect any impact from urban development on these wetland systems. Water quality in urban swamps was consistent with the freshwater salinisation syndrome despite all the swamps having relatively low electrical conductance (<140 µS cm⁻¹). Urban swamp water had salinity (mean 87.3 µS cm⁻¹) three times that of non-urban swamps (mean 28 µS cm⁻¹). The ionic composition of urban swamp water was dominated by calcium and bicarbonate, consistent with urban alkalisation syndrome. Our guidelines instead recommend limits for pH, salinity, turbidity, dissolved oxygen, and metals detected in greater concentrations that were found in urban swamps (iron, manganese, barium, and strontium). Our results support the theory that the dissolution of urban concrete materials is a degradation process that contributes to the impairment of urban swamp water quality. Full article

The Australian alpaca industry is continuing to develop as an alternative fibre industry to the traditional merino or angora industries. This study aimed to investigate herd behaviour in an extensive system in south eastern Australia. Healthy adult female alpacas (Huacaya n = 32, Suri n = 32) over two years old were inducted into the trial and kept together across a 10 month period. A total of 5 animals were removed during the study due to illthrift or death unrelated to the study. GoPro cameras were set up at 5 locations in the paddock for 3 days in the middle of every season (Summer, Autumn, Winter, Spring) to record alpaca behaviour without a human observer present. Visual observations were taken at 0800, 1000, 1100, 1300, 1500 for 60 min. Behaviour observations were taken every 5 min from the videos according to a prepared ethogram. A count of animals exhibiting each behaviour was recorded at each time point within each of the designated 60-minute periods. A generalised linear mixed-effects model (GLMM) was run on binary data for each behaviour. Behaviours that returned a predicted proportion of over 0.10 for all seasons were used in an ordinal logistic regression that was then utilised to determine the effect of the season, time of day, and weather conditions on the number of animals. Season significantly impacted the number of alpacas grazing, resting, and standing (p < 0.0001). Alpacas were more likely to be grazing throughout the day in cooler seasons (autumn, winter) and resting in the warmer parts of the day in summer and spring. The time of day impacted the proportion of alpacas resting and grazing (p < 0.05) but not standing (p = 0.4432). This study highlights that alpacas spend the majority of the daylight hours grazing, with some variability across different seasons, which may impact ideal management practices to optimise production in an extensive system. Full article

Fusarium circinatum poses severe threats to agroforestry ecosystem as a globally significant pathogenic fungus. This study utilized multi-source species distribution data and environmental variables (climatic, topographic, and soil factors) to predict the global potential habitat suitability of F. circinatum and its response to future climate change using an optimized MaxEnt model (RM = 1, FC = LQ). The results indicate that the current total suitable area spans approximately 69.29 million km², with highly suitable habitats (>0.493) accounting for 15.07%, primarily concentrated in East Asia, southwestern North America, western South America, the Mediterranean coast, and eastern Australia. The distribution of F. circinatum’s suitable habitats is primarily constrained by the following environmental factors, ranked by contribution rate: coldest quarter precipitation (29.4%), coldest quarter mean temperature (18.2%), annual mean temperature (17.2%), and annual precipitation (12%). Under future climate scenarios, the suitable habitats exhibited an overall contraction and poleward shift, with the most significant decline in highly suitable areas observed under SSP370-2050s (−52.1%). The centroid of suitable habitats continuously migrated northwestward from Gombe State, Nigeria, with the maximum displacement reaching 1077.6 km by SSP585-2090s. This study reveals a latitude gradient redistribution pattern of F. circinatum driven by climate warming, providing a scientific basis for transboundary biosecurity and early warning systems. Full article

The pepper weevil Anthonomus eugenii is a devastating pest native to Central America that can cause severe damage to over 35 pepper varieties. Global trade in peppers has significantly increased the risk of its spread and expansion. Moreover, future climate change may add more uncertainty to its distribution, resulting in considerable ecological and economic damage globally. Therefore, we employed an ensemble model combining Random Forests and CLIMEX to predict the potential global distribution of A. eugenii in historical and future climate scenarios. The results indicated that the maximum temperature of the warmest month is an important variable affecting global A. eugenii distribution. Under the historical climate scenario, the potential global distribution of A. eugenii is concentrated in the Midwestern and Southern United States, Central America, the La Plata Plain, parts of the Brazilian Plateau, the Mediterranean and Black Sea coasts, sub-Saharan Africa, Northern and Southern China, Southern India, Indochina Peninsula, and coastal area in Eastern Australia. Under future climate scenarios, suitable areas in the Northern Hemisphere, including North America, Europe, and China, are projected to expand toward higher latitudes. In China, the number of highly suitable areas is expected to increase significantly, mainly in the south and north. Contrastingly, suitable areas in Central America, northern South America, the Brazilian Plateau, India, and the Indochina Peninsula will become less suitable. The total land area suitable for A. eugenii under historical and future low- and high-emission climate scenarios accounted for 73.12, 66.82, and 75.97% of the global land area (except for Antarctica), respectively. The high-suitability areas identified by both models decreased by 19.05 and 35.02% under low- and high-emission scenarios, respectively. Building on these findings, we inferred the future expansion trends of A. eugenii globally. Furthermore, we provide early warning of A. eugenii invasion and a scientific basis for its spread and outbreak, facilitating the development of effective quarantine and control measures. Full article

The likely increase in the frequency and severity of droughts with climate warming will pose an enormous challenge for the conservation of forest biodiversity. Documenting the response of species to recent droughts can inform future conservation actions. Mammals that breed and mature slowly may be especially vulnerable to drought-induced disruption to breeding. The yellow-bellied glider (Petaurus australis, Shaw) is a threatened low-density, arboreal marsupial of eastern Australia. Following a severe drought in 2019, one population had declined by 48% by 2021. The present study investigated whether this population had recovered 3–4 years (2022 and 2023) after that drought. Audio surveys of this highly vocal species were conducted at 42 sites, sampling > 1000 h per year, and producing recordings of 2038–2856 call sequences. The probability of occupancy varied little across the two survey years (0.92–0.97). Local abundance in 2023 had returned to pre-drought levels (45% of occupied sites had ≥3 individuals compared to 6% in 2021). These findings show a recovery from a drought-induced decline required at least 3 years, in keeping with the slow life history traits of this species. This study highlights the importance of considering a species’ life history strategy when evaluating its sensitivity to drought. Full article

As one component of a study to improve Medicago spp. germplasm in eastern Australia, fifteen phenotypic and agronomic attributes were recorded for 4715 plants grown from the seed of 90 accessions of the widely naturalized pasture legume Medicago polymorpha from 90 sites in eight regions of inland New South Wales. The species expressed wide polymorphism. However, many leaflet attributes were associated with specific climate and soil characteristics, which varied from east to west across the collection zone. Discriminant analysis showed that accessions from the four most northern (summer dominant rainfall) and western (arid–semiarid) regions (Group A) differed from accessions from the most southern, temperate (winter dominant rainfall) and eastern (higher rainfall) regions (Group B). Group A flowered earlier and had shorter pod spines. Group B had lower plant vigor. Regions from which Group A accessions were collected had higher soil pH, lower winter rainfall, and higher minimum winter temperature than Group B regions. The diversity in the population, particularly the difference in flowering times among accessions collected from drier, warmer regions and those from more mesic, cooler regions, and the wide variation in flowering time measured among plants grown from accessions within all collection regions, is likely to ensure the long-term persistence of M. polymorpha in a changing climate. Elite lines were subsequently identified and lodged in National and International Genebanks for future research. Full article

Tetragonia tetragonioides, or New Zealand spinach, is a widespread halophyte native to eastern Asia, Australia, and New Zealand, and naturalized in some Mediterranean regions. This underutilized vegetable is consumed for its leaves, raw or cooked. For the first time, we investigated the feasibility of using whole baby plants (including stems and leaves) as raw material for ready-to-eat (RTE) vegetable production. Our study assessed Tetragonia’s suitability for hydroponic cultivation over two cycles (autumn–winter and spring). We investigated the impact of increasing nutrient rates (only water, half-strength, and full-strength nutrient solutions) and plant densities (365, 497, and 615 plants m⁻² in the first trial and 615 and 947 plants m⁻² in the second) on baby plant production. We also analyzed the plants’ morphological and biochemical characteristics, and their viability for cold storage (21 days at 4 °C) as a minimally processed product. Tetragonia adapted well to hydroponic cultivation across both growing periods. Nevertheless, climatic conditions, plant density, and nutrient supply significantly influenced plant growth, yield, nutritional quality, and post-harvest storage. The highest plant density combined with the full-strength nutrient solution resulted in the highest yield, especially during spring (1.8 kg m⁻²), and favorable nutritional characteristics (β-carotene, Vitamin C, Fe, Cu, Mn, and Zn). Furthermore, Tetragonia baby plants proved suitable for minimal processing, maintaining good quality retention for a minimum of 14 days, thus resulting in a viable option for the RTE vegetable market. Full article

Toenail onychomycosis causes significant problems in public health and is more common among the elderly and immune-compromised populations. A previous culture-based survey of communal finely ground toenails from the east coast of Australia isolated 125 T. interdigitale but only one T. rubrum. This paucity of T. rubrum was surprising because it is one of the most common dermatophytes isolated worldwide. Our aim was to find out if T. rubrum was present but not cultured. DNA was extracted from ground toenails from the same samples. New specific primers were designed for the ITS region of T. rubrum that excluded T. interdigitale and vice versa. PCR with these new primers found T. rubrum as well as T. interdigitale in all ground toenail samples. This suggests that T. rubrum was present and common in the ground toenails. It was possibly missed by culture because it grows slowly and was overgrown by T. interdigitale and non-dermatophyte moulds. Alternatively, its viability may have declined earlier, during collection, treatment, or storage of the ground toenails. This has implications for studies of clinical materials, especially nails, as infection by T. rubrum (the most common dermatophyte) may be missed by culture, the main method used in pathology laboratories. Full article

Understanding how urbanisation and habitat fragmentation influence wildlife is critical for biodiversity conservation. Fragmentation and population isolation can reduce genetic diversity, yet few studies have assessed these genetic impacts in urbanised environments. Eastern grey kangaroos (Macropus giganteus), widespread across eastern Australia, often inhabit landscapes shaped by urbanisation. Using single nucleotide polymorphism (SNP) data from scat and tissue samples, we compared genetic characteristics of kangaroo populations in urban and non-urban areas across three regions. We assessed the influence of habitat isolation on genetic diversity and relatedness at 18 study sites. Overall, urban populations did not show significantly lower genetic diversity than those in less developed areas (p > 0.05; Urban mean H_O = 0.196, Non-urban mean H_O = 0.188). However, populations fully isolated by roads, buildings, and fences exhibited reduced genetic diversity and increased inbreeding. Additionally, significant genetic differences were observed among regions. These findings suggest that while urbanisation alone may not always reduce genetic diversity, complete physical isolation poses greater risks to population genetic health. This study highlights how urban landscape features can shape the genetics of large terrestrial mammals and underscores the need for spatially informed urban planning and management strategies that maintain or restore habitat connectivity. Full article

This study utilized Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite level-2 data with high-confidence cloud–aerosol discrimination (|CAD| > 70) to investigate the optical properties, vertical distributions, seasonal variations, and aerosol interactions of near-surface cloud layers (cloud base height < 2.5 km) over Australia from 2006 to 2021. This definition encompasses both traditional low clouds and part of mid-level clouds that extend into the lower troposphere, enabling a comprehensive view of cloud systems that interact most directly with boundary-layer aerosols. The results showed that the optical depth of low clouds (CODL) exhibited significant spatial heterogeneity, with higher values in central and eastern regions (often exceeding 6.0) and lower values in western plateau regions (typically 4.0–5.0). CODL values demonstrated clear seasonal patterns with spring peaks across all regions, contrasting with traditional summer-maximum expectations. Pronounced diurnal variations were observed, with nighttime CODL showing systematic enhancement effects (up to 19.29 maximum values compared to daytime 11.43), primarily attributed to surface radiative cooling processes. Cloud base heights (CBL) exhibited counterintuitive nighttime increases (41% on average), reflecting fundamental differences in cloud formation mechanisms between day and night. The geometric thickness of low clouds (CTL) showed significant diurnal contrasts, decreasing by nearly 50% at night due to enhanced atmospheric stability. Cloud layer number (CN) displayed systematic nighttime reductions (18% decrease), indicating dominance of single stratiform cloud systems during nighttime. Regional analysis revealed that the central plains consistently exhibited higher CODL values, while eastern mountains showed elevated cloud heights due to orographic effects. Correlation analysis between cloud and aerosol layer properties revealed moderate but statistically significant relationships (|R| = 0.4–0.6), with the strongest correlations appearing between cloud layer heights and aerosol layer heights. However, these correlations represent only partial influences among multiple factors controlling cloud development, suggesting measurable but modest aerosol effects on cloud properties. This study provides comprehensive observational evidence for cloud optical property variations and aerosol–cloud interactions over Australia, contributing to an improved understanding of Southern Hemisphere cloud systems and their climatic implications. Full article

Thunderstorms downbursts can be hazardous during aircraft landing and take-off. A warming climate increases low- to mid-level troposphere water vapor, typically transported from high sea-surface temperature regions. Consequently, the future occurrence and intensity of destructive wind gusts from wet microburst thunderstorms are expected to increase. Wet microbursts are downdrafts from heavily precipitating thunderstorms and are several kilometers in diameter, often producing near-surface extreme wind gusts. Brisbane airport recorded a wet microburst wind gust of 157 km/h in November 2016. Numerous locations in eastern Australia experience warm season (October to March) wet microbursts. Here, eight machine learning techniques comprising forward and backward linear regression, radial basis forward and backward support vector regression, polynomial-based forward and backward support vector regression, and forward and backward random forest selection were employed. They identified primary attributes for increased atmospheric instability by warm moist air influx from regions of high sea-surface temperatures. The climate drivers detected here are indicative of increased future eastern Australian warm season thunderstorm downbursts, occurring as wet microbursts. They suggest a greater frequency and intensity of impacts on aircraft safety and operations affecting major east coast airports, such as Sydney and Brisbane, and smaller aircraft at inland regional airports in southeastern Australia. Full article

Severe bushfires in South-Eastern Australia during the summer of 2019/2020 killed tens of thousands of livestock, while many more survived on fire-affected properties. At the time, the literature on bushfire and livestock in Australia primarily described animals with burns. The mid- to long-term health effects, if any, of fire exposure and the effectiveness of recovery activities for surviving animals and farm enterprises were rarely reported. This study aimed to describe the key impacts of bushfire exposure on the health, welfare, and management of surviving cattle and sheep to inform recommendations for future fire-affected farmers and to guide future research. As part of a broad research programme, data on bushfire experiences, consequences for the livestock and the farm enterprise, and lessons learnt were gathered through face-to-face interviews and an online survey, collating information from 58 fire-affected farmers. A variety of health conditions at low frequency were reported in livestock surviving bushfires, including respiratory disease, eye disease, ruminal acidosis, lameness, and plant toxicities. No single disease was observed widely across participating farms, with many conditions likely associated with management changes post-fire rather than direct fire exposure. A variety of management and farm biosecurity challenges were also described by farmers. Key strategies for the prevention and treatment of health conditions in livestock post-bushfire include supporting effective farm management through the challenges of post-fire recovery and early detection for treatment on a case-by-case basis. Full article

There is limited investigation of the alpaca microbiome on a global scale, with no previous research conducted in Australia characterising the faecal microbiome. The microbiome composition in other ruminants has been shown to impact feed efficiency, average daily gain and methane production. This study aimed to characterise the faecal microbiome of alpacas raised in south-eastern Australia and identify variation across geographic regions. Faecal samples were collected from 59 healthy adult female alpacas, aged between 15 months and 17 years in NSW, Australia. Firmicutes were identified as the dominant phyla, accounting for 57.78% of the cumulative abundance, followed by Bacteroidota (29.12%). These two phyla accounted for 90% of the taxa, with the cumulative abundance of Firmicutes and Bacteriodota significantly differing (p < 0.05) across locations. There was no effect of age on the frequency of microbes identified at either phyla or class levels. The alpaca’s production status only significantly affected the abundance of Firmicutes Clostridia Oscillospirales (p = 0.0026). The breakdown of the alpaca faecal microbiome identified here is consistent with previous ruminant and camelid studies. This study provides a valuable baseline for the microbiome characterisation of alpacas in south-eastern Australia and can be used as a baseline for further microbiome studies. Full article

In a 1975 review, red kangaroos in the arid rangelands of Australia were said to be favoured with an anomalous prosperity following the introduction of ruminant livestock. In the western and central locations reviewed, this was not sustained, but in the sheep rangelands of Southern Australia, it is often claimed that such prosperity continues. Here, as elsewhere, the marsupial herbivore guild (kangaroos, wallabies, bettongs and bandicoots) has been simplified by the extinction of the smaller species (the anomaly), while large kangaroos remain abundant. However, the mammalian herbivore guild has gained complexity with not only the introduction of managed ruminant livestock, some of which run wild, but also game like rabbits. We studied the population dynamics, habitat selection and individual mobility of red, western and eastern grey kangaroos, common wallaroos, Merino sheep, feral goats and European rabbits at Fowlers Gap Station in far northwestern New South Wales, Australia. This site is representative of the arid chenopod (Family: Chenopodiaceae) shrublands stocked with sheep, where sheep and red kangaroos dominate the mammalian herbivores by biomass. The study site comprised two contiguous pairs of stocked and unstocked paddocks: a sloping run-off zone and a flat run-on zone, covering a total area of 2158 ha. This three-year study included initial rain-deficient (drought) months followed by more regular rainfall. Red kangaroos showed avoidance of sheep when given the opportunity and heightened mobility in response to localized drought-breaking storms and dispersion of the sheep flock at lambing. Western grey kangaroos were sedentary and did not dissociate from sheep. These effects were demonstrated at the population level and the individual level through radio-tracking a small cohort of females. The other kangaroo species and goats were transient and preferred other habitats. Rabbits were persistent and localized without strong interactions with other species. The results are discussed with a focus on the red kangaroo and some causes for its resilience in the sheep rangelands. Full article

Giant clams are ecologically important coral reef animals, with many species facing imminent local extinction. While many regions have undertaken recent assessments of their biodiversity assets, persistent gaps remain even in otherwise well-surveyed areas. This study sought to understand the geographic distribution of smaller-bodied and morphologically similar giant clams, specifically Tridacna maxima and T. noae, in the eastern Indian Ocean. Due to the difficulties in reliably identifying these species using morphological characters, we confirmed species identity and investigated intraspecific variation using sequence data from the mitochondrial cytochrome C oxidase subunit I gene (COI). Seventy whole animal vouchers were newly sampled from a 1500 km span of remote northwestern Australian coastline over a decade, as part of an ongoing coral reef survey expedition of the Western Australian Museum and partners. Tridacna maxima had a limited distribution and was only genotyped from offshore oceanic reefs in the Rowley Shoals and Cocos Keeling Islands. In contrast, T. noae was well established beyond Ningaloo Reef, and was abundant at inshore sites throughout the Pilbara and Kimberley, and even offshore to Ashmore Reef. Phylogeographically, T. maxima did not group with conspecifics from the Western Pacific Ocean, including the east coast of Australia, but instead clustered with individuals from Malaysia, China, Taiwan, and Indonesia; T. noae exhibited a similar pattern. The affinity of Western Australian individuals with representatives from the Indo-Malay region and not eastern Australia will be an important consideration for these commercially important species. Novel haplotypes in both tested species occur in Western Australia. Continued sampling of eastern and central Indian Ocean giant clams, especially to continue to document the range of T. noae, is encouraged to understand connectivity in this basin. Together, these findings contribute to an improved baseline for conservation initiatives of these iconic coral reef animals in Western Australia. Full article