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This document is a compilation of research papers and case studies that explore the impact of climate change on habitat restoration in Australia. It discusses various strategies to make restoration efforts more resilient, including altering planting timing, using older/deeper-rooted individuals, and direct seeding. The papers also cover topics such as the use of non-native species in restoration projects, the impacts of climate change on native and non-native species, and the importance of considering climate change in restoration planning. The document emphasizes the need for a national model of seed collection and storage and encourages ecologists and practitioners to be innovative in their approaches. The author acknowledges the traditional owners of the land and expresses gratitude to individuals who provided feedback on the manuscript. [Extracted from the article]

Cooper Creek is one of Australia's largest unregulated river systems and one of the world's most variable large river systems. It is a dynamic environment that oscillates between booms and busts; yet, many species thrive in it. One of these species, the Cooper Creek turtle (Emydura macquarii emmotti) has received little attention, despite being one of Australia's largest freshwater turtles and living further inland than any other Australian turtle. We conducted surveys for E. m. emmotti in 2001–2004, 2019, and 2022, focussing predominantly on the Waterloo waterhole. Waterloo had a large population of E. m. emmotti (508 estimated individuals; 95% CI = 447–596) with an estimated density of 64.8 turtles/ha (95% CI = 57.0–76.2) and estimate biomass of 74.4 kg/ha (95% CI = 57.6–100.3 kg/ha). Juveniles were highly abundant in all years, representing up to 63.6% of captured individuals. It was slightly (but not significantly) male‐biased in 2001–2004 and significantly female‐biased in 2019. All sizes and sexes used the floodplain during a flooding event in 2022, but more males than females were captured on the floodplain, and there was evidence of male‐biased dispersal across the years. Compared to Murray River turtles (Emydura macquarii macquarii), E. m. emmotti exhibited megacephaly across all ages and sexes, with particularly pronounced megacephaly in adult females. Algae were present on many individuals (including on the skin and plastron) but was relatively more abundant on juveniles. Leeches were not detected on any of the 66 turtles that were examined for them. The following injuries/malformations were noted: missing or injured limbs (3.2%), missing or injured eyes (1.3%), damaged shells (8.0%), scute/shell anomalies and malformations (10.6%), and marginal scute seams extending into the costals (67.4% of adults, 1.2% of juveniles). This paper presents some of the first work on this unusual turtle and makes recommendations for future research. [ABSTRACT FROM AUTHOR]

Wind energy is a rapidly expanding renewable technology with massive global investments; however, operating turbines are associated with bat strikes globally, and evidence suggests that without intervention, wind farm collisions could drive some common species to extinction. One widely regarded method for reducing strike mortality is operational mitigation, or curtailment, where turbine operation is restricted at low wind speeds. Despite an increasing number of studies in the Northern Hemisphere demonstrating curtailment effectiveness, no empirical studies have yet been conducted in Australia. This paper reports the findings of a curtailment study implemented at the Cape Nelson North wind farm in southwest Victoria, Australia. Conservation detection dog teams conducted mortality surveys between January and April in 2018 (before; pre‐curtailment) and 2019 (after; during curtailment). Results were consistent with similar studies in the USA and Europe, as curtailment significantly reduced pooled species mortality by 54%. Bat calls did not decline during the study period, and thus were not an explanation for the reduction in fatalities. This study demonstrates that curtailment is a valid method for reducing bat turbine collision in south‐eastern Australia. Consideration should be given to curtailment as a means to reduce bat turbine impacts in Australia, particularly at sites with known endangered and threatened populations, as we act to reduce anthropogenic climate change and its time‐sensitive negative consequences. [ABSTRACT FROM AUTHOR]

Indigenous biocultural knowledge offers valuable insights for species conservation; however, like biological diversity, associated cultural knowledge is also often threatened. This paper demonstrates how Indigenous biocultural knowledge of species can contribute to addressing gaps in species occurrence data and conservation knowledge using a case study from the South East Arnhem Land Indigenous Protected Area (SEAL IPA), northern Australia. Using a series of mapping workshops and interviews this collaborative project recorded Indigenous biocultural knowledge of the distribution, ecology, cultural significance and threats to freshwater turtles (freshwoda teduls in the local Indigenous language, Roper River Kriol). Based on past freshwoda tedul hunting experiences, 74 Indigenous knowledge holders identified 753 past freshwoda tedul occurrences, significantly adding to the 12 occurrences previously listed for the SEAL IPA in Australia's online species database, the Atlas of Living Australia. Importantly, these were the first 'memory' records of past species sightings by Indigenous people to be recognized and added to Australia's national species database. In addition, a blog summarizing this research was promoted through the Atlas of Living Australia, raising awareness of the Indigenous biocultural knowledge associated with these species. The Mepimbat tedul proujek revealed the cultural significance of freshwoda teduls and reported declines in abundance since the turn of the century, implicating invasive hard‐hooved ungulates (buffalo, pig) and reduced rainfall. The addition of non‐sacred Indigenous knowledge to free online species databases may offer innovative solutions for storage, interaction and sharing of indigenous knowledge, with opportunities for intergenerational and cross‐cultural learning and broader application in conservation management and decision‐making. [ABSTRACT FROM AUTHOR]

The Ecological Society of Australia was founded in 1959, and the society's journal was first published in 1976. To examine how research published in the society's journal has changed over this time, we used text mining to quantify themes and trends in the body of work published by the Australian Journal of Ecology and Austral Ecology from 1976 to 2019. We used topic models to identify 30 'topics' within 2778 full‐text articles in 246 issues of the journal, followed by mixed modelling to identify topics with above‐average or below‐average popularity in terms of the number of publications or citations that they contain. We found high inter‐decadal turnover in research topics, with an early emphasis on highly specific ecosystems or processes giving way to a modern emphasis on community, spatial and fire ecology, invasive species and statistical modelling. Despite an early focus on Australian research, papers discussing South American ecosystems are now among the fastest‐growing and most frequently cited topics in the journal. Topics that were growing fastest in publication rates were not always the same as those with high citation rates. Our results provide a systematic breakdown of the topics that Austral Ecology authors and editors have chosen to research, publish and cite through time, providing a valuable window into the historical and emerging foci of the journal. [ABSTRACT FROM AUTHOR]

This review clarifies important points on habitat selection by the Swamp Rat Rattus lutreolus (Rodentia: Muridae), a species that has been the subject of much research in Australia and has provided a useful model for understanding ecological and biological processes. It also provides an opportunity to cite important earlier research, not readily available through electronic search engines, thus bringing it into current literature to avoid its disappearance into Internet obscurity. We comment on some papers in the literature to correct errors detected and to emphasize the importance of due care in all aspects of a research project, including its reporting. We show that both floristic and structural components have been reported as important to an understanding of habitat and microhabitat selection by R. lutreolus and conclude that it is vegetation density that is of paramount importance. Female R. lutreolus are clearly dominant in driving microhabitat selection, occupying the ‘best’ or densest habitats with male R. lutreolus occupying the next best and Pseudomys or other species, where present occupying the remainder. This demonstrates the important role that intraspecific and interspecific competition play in determining habitat selection. Direct predation and the perception of predation risk may also play a role in habitat selection, again perceived to be pushing individuals towards denser vegetation, representing ‘better cover’. Whether these effects operate as bottom-up or top-down needs careful consideration. Climatic variables, such as ENSO-affecting productivity, and related variables such as temperature and humidity may also play important roles in habitat selection, as can disturbance effects such as wildfire. The relative importance of all of these potential determining factors may vary from place to place, particularly when climatic clines are involved. [ABSTRACT FROM AUTHOR]

The 19 BIOCLIM variables available from the WorldClim databases have become the most widely used set of climatic variables for creating species distribution models (SDMs) and ecological niche models (ENMs). Nevertheless, in recent years, there has been an increasing trend to exclude four of these variables from SDM/ENM analyses. The four values concerned are interactive as they combine both temperature and precipitation assessments. Their exclusion was justified initially due to discontinuities in their interpolated surfaces observed in a study using data from version 1 of WorldClim. The discontinuities were thought to be artefacts of the measures used, and such sudden changes were unlikely to be biologically meaningful. A freely available biodiversity database and an open access geographic information system were used here to check the four interactive variables for discontinuities in data from both versions 1 and 2 of WorldClim. Over most of the world, the four interactive BIOCLIM variables from WorldClim were found to change smoothly. Major and minor discontinuities, however, were noted for all four variables in specific parts of some of the six continents (excluding Antarctica) covered by WorldClim databases. Discontinuities were related to sudden changes in the quarterly periods used to calculate the variables. These discontinuities were often found in equatorial regions where there are only small changes in temperature across the year. Bimodal precipitation distributions may also cause problems. It is recommended that the quick and simple method described here should be used to facilitate visual inspection and numerical checking for possible discontinuities of these variables before SDM/ENM analyses. If discontinuities are found for an interactive variable in the study area, it is recommended that the variable should not be used. Ways in which the four variables could be recalculated when new databases are created are suggested to reduce discontinuity problems. [ABSTRACT FROM AUTHOR]

In comparison with drylands elsewhere, the unpredictability of rainfall in central Australia is globally distinctive. The transformative rhythms of arid Australia reflect extremes of climatic conditions rather than seasons, and are characterized by irregular pulses of productivity that punctuate long periods of drought. These decadal-scale dynamics are only now beginning to be understood. Further complications in predicting and managing the biological processes within these landscapes arise from the vast spatial extent of arid and semi-arid communities, and increasing recognition of the heterogeneities that drive the formation of patterns across multiple scales. In 2010 and 2011 flooding rains broke long-standing rainfall records and triggered an anticipated greening of the typically dry red landscapes of central Australia. These unusual climatic events provided an unparalleled opportunity to test ideas about productivity and function, bottom-up versus top-down effects, and differential responses of biota that reflect landscape connections and heterogeneity. Migrations of species outside their known ranges, irruptions of rodents and redistribution of resources are just a few of the novel observations that were reported. The transformation of the landscape also presented land managers with challenges stemming from the influx of invasive species that trigger novel ecological interactions and processes. The papers presented in this special issue describe how ecologists and managers responded to the unprecedented rainfall events, key lessons that we have learnt, and practical recommendations on how to improve conservation outcomes for the fragile inland environment into the future. [ABSTRACT FROM AUTHOR]

Long-term ecological studies (LTES) are critical for understanding and managing landscapes. To identify important research gaps, facilitate collaborations and communicate results, several countries have established long-term ecological research networks. A few initiatives to create such a network in Australia have been undertaken, but relatively few published data exist on the current state of LTES in Australia. In this paper, we present the results of an online survey of terrestrial LTES projects sent to academic, government and non-governmental organization-based researchers across Australia. We asked questions pertaining to the focus, scope, support and outcomes of LTES spanning 7 years or longer. Based on the information reported from 85 Australian LTES, we: (i) identify the biomes, processes and species that are under-represented in the current body of research; (ii) discuss important contributing factors to the successful development and survival of these projects; and (iii) make recommendations to help increase the productivity and influence of LTES across research, management and policy sectors. [ABSTRACT FROM AUTHOR]

Vegetation maps are critical biodiversity planning instruments, but the classification of vegetation for mapping can be strongly biased by survey design. Standardization of survey design across different vegetation types is therefore increasingly recommended for vegetation mapping programs. However, some vegetation types have complex small-scale vegetation patterns that are important in characterizing these vegetation types, and standard designs will often not capture these patterns. The objective of this paper was to investigate the magnitude of potential map bias that results from survey design standardization and recommend approaches to deal with this bias. We surveyed upland swamps of the Greater Blue Mountains World Heritage Area Australia using two contrasting survey designs, including the standard 400 m2 single quadrat design recommended and used by authorities. We then derived a classification for these swamps and tested the effect of survey design on this classification, species richness and the type of species detected (obligate or facultative swamp species). Species richness and species type were not significantly different among survey techniques. However, more than 40% of swamps clustered differently among survey designs. Thus, one of the 10 derived communities (which is floristically consistent with a previously mapped endangered community) was indistinct, and some individual swamps misclassified using the standard survey design. An effect of landscape position on swamp floristic patterns and a significant trend for high similarity scores among swamps surveyed with multiple small quadrats compared to the standard survey design was also determined. Australian upland swamps are classified at the global scale as shrub-dominated wetlands, and complex floristic patterns have been recorded in shrub-dominated wetlands in both northern and southern hemispheres. We therefore advocate either multiple survey designs or different survey standards for upland swamp communities and other vegetation types that have complex floristic patterns at small scales. [ABSTRACT FROM AUTHOR]

In 2050, which aspects of ecosystem change will we regret not having measured? Long-term monitoring plays a crucial part in managing Australia's natural environment because time is a key factor underpinning changes in ecosystems. It is critical to start measuring key attributes of ecosystems - and the human and natural process affecting them - now, so that we can track the trajectory of change over time. This will facilitate informed choices about how to manage ecological changes (including interventions where they are required) and promote better understanding by 2050 of how particular ecosystems have been shaped over time. There will be considerable value in building on existing long-term monitoring programmes because this can add significantly to the temporal depth of information. The economic and social processes driving change in ecosystems are not identical in all ecosystems, so much of what is monitored (and the means by which it is monitored) will most likely target specific ecosystems or groups of ecosystems. To best understand the effects of ecosystem-specific threats and drivers, monitoring also will need to address the economic and social factors underpinning ecosystem-specific change. Therefore, robust assessments of the state of Australia's environment will be best achieved by reporting on the ecological performance of a representative sample of ecosystems over time. Political, policy and financial support to implement appropriate ecosystem-specific monitoring is a perennial problem. We suggest that the value of ecological monitoring will be demonstrable, when plot-based monitoring data make a unique and crucial contribution to Australia's ability to produce environmental accounts, environmental reports (e.g. the State of the Environment, State of the Forests) and to fulfilling reporting obligations under international agreements, such as the Convention on Biological Diversity. This paper suggests what must be done to meet Australia's ecological information needs by 2050. [ABSTRACT FROM AUTHOR]

Habitat modification and invasive species are significant drivers of biodiversity decline. However, distinguishing between the impacts of these two drivers on native species can be difficult. For example, habitat modification may reduce native species abundance, while an invasive species may take advantage of the new environment. This scenario has been described as the driver-passenger model, with 'passengers' taking advantage of habitat modification and 'drivers' causing native species decline. Therefore, research must incorporate both habitat modification and invasive species impact to successfully investigate native species decline. In this paper, we used the common myna ( Acridotheres tristis) as a case study to investigate the driver-passenger model. We investigated changes in bird abundance, over 2 years, in relation to different habitat types and common myna abundance. We hypothesized that the common myna is both a passenger of habitat change and a driver of some bird species decline. Our results indicated that the abundance of many native species is greater in high tree density nature reserves, while the common myna was uncommon in these areas. Common myna abundance was almost three times higher in urban areas than nature reserves and declined rapidly as tree density in nature reserves increased. Our findings indicated that the common myna is primarily a passenger of habitat change. However, we also observed negative associations between common myna abundance and some bird species. We stress the importance of simultaneously investigating both invasive species impact and habitat modification. We suggest habitat restoration could be a useful tool for both native species recovery and invasive species control. Understanding the drivers of native species decline will help inform impact mitigation and direct further research. [ABSTRACT FROM AUTHOR]

Translocated from their native range in the Americas in 1935, cane toads ( Rhinella marina, Bufonidae) have now spread through much of tropical and subtropical Australia. The toad's invasion and impact have attracted detailed study. In this paper, I review information on ecological interactions between cane toads and Australian anurans. The phylogenetic relatedness and ecological similarity between frogs and toads creates opportunities for diverse interactions, ranging from predation to competition to parasite transfer, plus a host of indirect effects mediated via impacts of toads on other species, and by people's attempts to control toads. The most clear-cut effect of toads on frogs is a positive one: reducing predator pressure by fatally poisoning anuran-eating varanid lizards. However, toads also have a wide range of other effects on frogs, some positive (e.g. taking up parasites that would otherwise infect native frogs) and others negative (e.g. eating frogs, poisoning frogs, competing with tadpoles). Although information on such mechanisms predicts intense interactions between toads and frogs, field surveys show that cane toad invasion has negligible overall impacts on frog abundance. That counter-intuitive result is because of a broad balancing of negative and positive impacts, coupled with stochastic (weather-induced) fluctuations in anuran abundance that overwhelm any impacts of toads. Also, the impacts of toads on frogs differ among frog species and life-history stages, and depend upon local environmental conditions. The impacts of native frogs on cane toads have attracted much less study, but may well be important: frogs may impose biotic resistance to cane toad colonization, especially via competition in the larval phase. Overall, the interactions between native frogs and invasive toads illustrate the diverse ways in which an invader's arrival can perturb the native fauna by both direct and indirect mechanisms, and by which the native species can curtail an invader's success. These studies also offer a cautionary tale about the difficulty of predicting the impact of an invasive species, even with a clear understanding of mechanisms of direct interaction. [ABSTRACT FROM AUTHOR]

Arid zone catchments experience extreme hydrological variability and some rivers are entirely ephemeral, replenished only by intermittent flooding. The ecological roles of ephemeral systems are rarely studied. This paper describes movement patterns of fish in the Mulligan River, an ephemeral system in the Lake Eyre Basin, central Australia. Several sites were sampled along a temporal gradient encompassing floods and dry periods. After a single major flood in 2007 up to seven fish species were found at sites up to 300 km from the closest permanent waterhole. Following a series of floods (when waterholes were replenished and remained wet between 2009 and 2011) a further five species were recorded including the first records for the Lake Eyre hardyhead, Craterocephalus eyresii, from the rivers of far western Queensland. The presence of all species known from the parent catchment (the Georgina, where permanent waterholes occur) in the ephemeral catchment (the Mulligan) suggests that many fish species present in the river systems of central Australia are capable of dispersing long distances following the opening of movement pathways during flooding. However, two distinct groups of species were identified: extreme dispersing species, that move as far as possible into intermittently wetted habitats, and conservative dispersing species, that do not move as far, tending to inhabit deeper waterholes within mid-reaches of the river that are more likely to hold water for longer. Preservation of the natural flow regime of Australia's arid-zone rivers is important for maintaining these fish communities and facilitating study of their adaptations to ephemerality. [ABSTRACT FROM AUTHOR]

It has been widely argued that the acquisition of novel disease resistance genes by wild host populations following the release of novel pathogen-resistant plants into agricultural systems could pose a significant threat to non-target plant communities. However, predicting the magnitude of ecological release in wild plant populations following the removal of disease remains a major challenge. In this paper we report on the second phase of a tiered risk assessment designed to investigate the role of disease on host growth, survival, fecundity and fitness in a model pathosystem (the pasture species Trifolium repens infected with Clover yellow vein virus, ClYVV) and to assess the level of risk posed to at-risk native plant communities in southeast Australia by newly developed genetically modified and conventionally bred virus-resistant T. repens genotypes. Multi-year field experiments conducted in woodland and grassland environments using host-pathogen arrays derived from 14 ClYVV isolates and 21 T. repens genotypes indicate that viral infection reduces fecundity, growth and survival of wild T. repens plants but that the severity of these effects depends on host tolerance to infection, isolate aggressiveness and specific spatial and temporal environmental conditions. Demographic modelling showed that by reducing host survival and growth, ClYVV also limits the intrinsic population growth rate and niche size of wild T. repens populations. Given the significant fitness cost associated with viral infection we conclude that virus-resistant T. repens genotypes may pose a threat to some high conservation-value non-target ecosystems in SE Australia. We also argue that long-term, multi-tiered experiments conducted in a range of controlled and non-controlled environments are necessary to detect and accurately quantify risks associated with the release of disease-resistant plants in general. [ABSTRACT FROM AUTHOR]

The need to improve environmental management in Australia is urgent because human health, well-being and social stability all depend ultimately on maintenance of life-supporting ecological processes. Ecological science can inform this effort, but when issues are socially and economically complex the inclination is to wait for science to provide answers before acting. Increasingly, managers and policy-makers will be called on to use the present state of scientific knowledge to supply reasonable inferences for action based on imperfect knowledge. Hence, one challenge is to use existing ecological knowledge more effectively; a second is to tackle the critical unanswered ecological questions. This paper identifies areas of environmental management that are profoundly hindered by an inability of science to answer basic questions, in contrast to those areas where knowledge is not the major barrier to policy development and management. Of the 22 big questions identified herein, more than half are directly related to climate change. Several of the questions concern our limited understanding of the dynamics of marine systems. There is enough information already available to develop effective policy and management to address several significant ecological issues. We urge ecologists to make better use of existing knowledge in dialogue with policy-makers and land managers. Because the challenges are enormous, ecologists will increasingly be engaging a wide range of other disciplines to help identify pathways towards a sustainable future. [ABSTRACT FROM AUTHOR]

Cyclone Larry (category 4) was the most severe cyclone to impact on the Wet Tropics bioregion since the devastating 1918 Innisfail cyclone. Based on an analysis of earlier cyclones impacting on this region over the period 1856–2006, it was determined that Larry was a ‘1 in 50 year’ event. This paper provides an overview of the landscape-scale impacts of Larry on the forest ecosystems of the Wet Tropics region, based on low-level helicopter surveys 2 weeks after the event. Cyclone Larry has been described as a ‘midget’ cyclone. Severe forest damage only extended about 30 km from the central track of the cyclone while moderate to severe damage extended some 50 km. Moderate to slight canopy disturbance was rarely identified more than 75 km from the centre of the cyclone's track. Beyond 75 km, forest damage was restricted to exposed areas of elevated terrain and in places exposed to strong lee (gravity) waves from the west. The ecological role of cyclones as important disturbance agents affecting the structure and function of forest ecosystems in the region is discussed, followed by an evaluation of likely effects of climate change on cyclone frequency and intensity. [ABSTRACT FROM AUTHOR]

Conservation monitoring in Australia has assumed increasing importance in recent years, as societal pressure to actively manage environmental problems has risen. More resources than ever before are being channelled to the task of documenting environmental change. Yet the field remains crippled by a pervasive lack of rigour in analysing, reporting and responding to the results of data collected. Millions of dollars are currently being wasted on monitoring programmes that have no realistic chance of detecting changes in the variables of interest. This is partly because detecting change in ecological systems is a genuinely difficult technical and logistical challenge. However, the failure to plan, fund and execute sophisticated analyses of monitoring data and then to use the results to improve monitoring methods, can also be attributed to the failure of professional ecologists, conservation practitioners and bureaucrats to work effectively together. In this paper, we offer constructive advice about how all parties involved can help to change this situation. We use three case studies of recent monitoring projects from our own experience to illustrate ways in which the disconnect between science and bureaucracy can be bridged and some obstacles to collecting and analysing ecologically meaningful data sets can be overcome. We urge a continuing discussion on this issue and hope to stimulate a change in the culture of conservation monitoring in Australia. [ABSTRACT FROM AUTHOR]

In arid and semiarid Australia fossorial vertebrates have been a major component of the soil biota mediating many fundamental landscape processes. However, many species such as the burrowing bettong ( Bettongia lesueur) have become seriously depleted following European pastoral settlement. As ‘landscape engineers’, they were responsible for creating and maintaining a high degree of surface heterogeneity that promoted a diverse and productive herbaceous understorey, particularly in ‘hard-red’ communities dominated by mulga ( Acacia aneura). While their regional extinction has had major impacts by contributing to desertification and loss of biodiversity, relict warrens ‘engineered’ by B. lesueur still remain in certain ecosystems and despite continual weathering, contribute significantly to herbage productivity and species diversity. This paper details the results obtained from a number of field studies aimed at determining the distribution of relict warrens at contrasting scales and their influence on landscape patch dynamics resulting from their impacts on soil nutrients, herbage composition and herbivory. Finally, the conservation implications following the continental extinction of this species and the resulting loss of fundamental ecosystem services, as well as cultural values, are discussed in the context of future re-introduction efforts. [ABSTRACT FROM AUTHOR]

The detection and mapping of canopy disturbance caused by natural events such as cyclones in tropical rainforests is important for monitoring and understanding rainforest dynamics and recovery. In February 1999 tropical cyclone Rona crossed the coastline of Far North Queensland, Australia, causing significant damage to the rainforest canopy in some areas. This paper examines the application of multitemporal canopy digital elevation models (DEMs) generated by a NASA-operated airborne radar mapping system called TOPSAR in 1996 and 2000, for detection of canopy disturbance caused by cyclone damage. Canopy damage was mapped here by identifying areas with a significant decrease in canopy height estimated from the difference of the 1996 and 2000 TOPSAR DEMs. Conventional aerial photographs, flown shortly after the cyclone (March 1999), were used to validate the resulting map of cyclone damaged rainforest canopy. The results showed that the DEM-derived canopy damage map performed reasonably well when comparing the spatial distribution and size of damaged areas, while taking into account the time difference between cyclone damage and the second radar acquisition. Some errors were encountered on the steeper slopes which were related to terrain distortions inherent in radar images of steep terrain. The height accuracy of the DEM was close to the depth of some of the gaps being mapped, which also contributed to errors. Even so, the results demonstrate there may be potential for weather-independent, regional-scale mapping of forest canopy change from imaging radar that is not always possible from traditional optical means of measuring canopy elevation, for example, airborne laser data and stereo aerial photography. This may be possible in relatively flat areas, provided the second radar acquisition occurs within months of the damaging event. Further algorithm refinement is required to improve its robustness and the range of topographies where this approach can provide reliable estimates of the extent of canopy disturbance. [ABSTRACT FROM AUTHOR]

Coarse woody debris (CWD) is the standing and fallen dead wood in a forest and serves an important role in ecosystem functioning. There have been several studies that include estimates of CWD in Australian forests but little synthesis of these results. This paper presents findings from a literature review of CWD and fine litter quantities. Estimates of forest-floor CWD, snags and litter from the literature are presented for woodland, rainforest, open forest and tall open forest, pine plantation and native hardwood plantation. Mean mass of forest floor CWD in Australian native forests ranged from 19 t ha−1 in woodland to 134 t ha−1 in tall open forest. These values were generally within the range of those observed for similar ecosystems in other parts of the world. Quantities in tall open forests were found to be considerably higher than those observed for hardwood forests in North America, and more similar to the amounts reported for coniferous forests with large sized trees on the west coast of the USA and Canada. Mean proportion of total above-ground biomass as forest floor CWD was approximately 18% in open forests, 16% in tall open forests, 13% in rainforests, and 4% in eucalypt plantations. CWD can be high in exotic pine plantations when there are considerable quantities of residue from previous native forest stands. Mean snag biomass in Australian forests was generally lower than the US mean for snags in conifer forests and higher than hardwood forest. These results are of value for studies of carbon and nutrient stocks and dynamics, habitat values and fire hazards. [ABSTRACT FROM AUTHOR]

Abstract This paper describes an assessment of the effect of exposure to fire-related cues (heat shock, smoke and nitrate) and the interactions between the cues on seed dormancy release of tropical savanna legumes in north-eastern Australia. Ten legume species were tested, comprising both native and exotic species. The ten species responded variously to the treatments. Brief exposure to temperatures between 80 and 100°C was found to break the seed dormancy of the native ephemeral herbs Chamaecrista mimosoides , Crotalaria calycina , Crotalaria montana , Indigofera hirsuta and Tephrosia juncea , as well as the exotic ephemeral herb Crotalaria lanceolata . Exposure to 80°C combined with treatment with a nitrate solution produced an additive effect on the germination of Chamaecrista mimosoides and Crotalaria lanceolata . However, the four species with the heaviest seeds, two exotic ephemeral herbs (Chamaecrista absus and Crotalaria pallida ) and two native perennials (Galactia tenuiflora and Glycine tomentella ) displayed no significant increase in germination with exposure to fire-related cues. Exposure to 120°C for 5 min produced seed mortality in all species tested. Two of the largest seeded species, Crotalaria pallida and Galactia tenuiflora , displayed the lowest tolerance to heat shock, with seed mortality after exposure to 100°C for 5 min. These data indicate that fire can promote the germination of some tropical savanna legumes. As a proportion of seeds of each species displayed no innate dormancy, some germination may occur in the absence of fire, especially of exotic species. [ABSTRACT FROM AUTHOR]

AbstractAustralia is unique in having two highly diverse plant genera, Eucalyptus and Acacia, that dominate the vegetation on a continent-wide scale. The recent shift in plantation forestry away from exotic Pinus radiata to native Eucalyptus species has resulted in much more extensive exchange of biota between native forest and plantation ecosystems than exchange in the past with plantations of exotic species. Growing numbers of hectares are being planted to Eucalyptus globulus across Australia, and plantations are providing resources and corridors for native biota. The present paper focuses on both the benefits and risks of having large-scale forestry plantations of native species that are closely related to dominant native taxa in local forests. At least 85 species of insects have been recorded as pests of Eucalyptus plantations around Australia; the vast majority of these have been insects using the same host species, or closely related taxa, in native forests. Plantations of native species may also benefit from closely related local forests through the presence of: (i) the diverse array of ectomycorrhizal fungi favourable for tree growth; (ii) natural enemies harboured in native habitats; and (iii) recruitment of other important mutualists, such as pollinators. Exchanges work in two directions: plantations are also likely to influence native forests through the large amount of insect biomass production that occurs in outbreak situations, or through the introduction or facilitation of movements for insects that are not native to all parts of Australia. Finally, older plantations in which trees flower may exchange genes with surrounding forest species, given the high degree of hybridization exhibited by many Eucalyptus species. This is an aspect of exchange for which few data have been recorded. In summary, because of Australia’s unique biogeography, plantation forestry using eucalypt species entails exchanges with natural habitats that are unparalleled... [ABSTRACT FROM AUTHOR]

AbstractOn the western Arnhem Land Plateau, Northern Territory, Australia, seedlings of the canopy tree Allosyncarpia ternata S.T. Blake typically spend many years (perhaps decades) as small (<1 m), multistemmed plants on the forest floor. In this establishment phase, long periods of apparent inactivity are interrupted by episodes of rapid growth. This paper describes a 5-year field-monitoring program to examine the pattern of seedling growth and survival in allosyncarpia forest, and field and shadehouse measurements of lignotuber size. Individual seedlings may produce, each wet season, a number of fast-growing stems, which then die back in the following dry season. As a result, mean annual above-ground growth during this life stage is negligible. With each wet season, however, the seedling extends its below ground parts – a large lignotuber and a deep root system. After a number of years, when the lignotuber has grown large enough to sustain massive shoot growth, when a suitable light gap becomes available, and presumably when roots reach reliable dry-season water supplies, the seedling grows rapidly. Thus, the shortage of saplings in allosyncarpia forest is due to the short time that individual plants spend at that particular growth-stage, rather than to any dysfunction in recruitment. [ABSTRACT FROM AUTHOR]

Perhaps one of the central questions in ecology has been what limits the geographic distribution of species. The geographic distributions of the reptile‐ticks Amblyomma limbatum, Bothriocroton hydrosauri and Amblyomma albolimbatum are a classic example of this problem: where these ticks meet, narrow regions‐of‐overlap often occur. Despite studies of interactions among these ticks, and of these ticks and their environment, we still do not understand what limits their geographic distributions. Many hypotheses have been proposed and tested, but all have seemingly been rejected. Our aim was to account for the abundance and the geographic distributions of A. limbatum and B. hydrosauri at Bundey Bore Station, South Australia, where these species come in contact and have been studied for over 35 years, leading to over 55 000 records of reptiles and their ticks using a capture‐mark‐recapture approach. We constructed models which had combinations of temperature and moisture indices from different months of the year to determine the relationship between climate and tick abundance, and between climate and the shifting local geographic distribution of A. limbatum and B. hydrosauri at Bundey Bore Station. We found that climate together with the abundance of ticks in the previous year and the abundance of the lizard host, accounted for 54%–77% of the variation in the abundance of A. limbatum and B. hydrosauri among years. We also found that the climate in late autumn to winter, together with the abundance of ticks and their host, accounted for 18%–84% of the variation in the geographic distributions of these ticks among years. Climate was central to the abundance and the geographic distributions of A. limbatum and B. hydrosauri at Bundey Bore Station. We speculate that the same mechanisms account for the geographic distributions of A. limbatum, B. hydrosauri and A. albolimbatum elsewhere in Australia; so, climate may explain the three‐tick problem in Austral ecology. [ABSTRACT FROM AUTHOR]

Bushfires burnt over 18 million hectares across Australia's east coast, including rainforests, over the spring and summer 2019/2020 period. Rainforest harbours a large percentage of Australia's biodiversity and does not usually burn and therefore understanding the extent and biodiversity implications was a priority. The National Indicative Aggregated Fire Extent Dataset (NIAFED) combined with detailed regional ecosystem (RE) mapping was used to estimate the perimeter and area of each of the burnt rainforest types within South East Queensland (SEQ). Previous biodiversity estimates for each rainforest regional ecosystem type combined with remnant ecosystem mapping data then enabled an assessment of the potential biodiversity impacts of the fires for SEQ rainforest. We found that 12% of the rainforest estate in SEQ was within the burn footprint (29 031 ha) including parts of the UNESCO World Heritage Gondwana Rainforests of Australia. Fifty per cent of the total remnant area of the Endangered rainforest type, semi‐evergreen vine thicket on Mesozoic to Proterozoic igneous rocks (RE: 12.12.17) was potentially burnt. This rainforest type has high diversity. Burn severity analysis found that the rainforest primarily burnt with low severity, however, there were patches of high severity. Accuracy assessment of severity mapping resulted in a weak correlation (0.57) due to the underestimation of ground fires in rainforest. As expected, we found rainforest‐suppressed fires. However, in contrast to expectations, we found the wettest rainforest types and putative past refugia burnt more than other rainforest types. These results suggest that given drought conditions any rainforest could burn, and we can expect that the area of rainforest will contract if both incidences of drought and wildfires increase due to climate change. [ABSTRACT FROM AUTHOR]

Predation by feral cats (Felis catus) has caused the extinction of many native species in Australia and globally. There is growing evidence that the impacts of feral cats can be amplified in post‐fire environments, as cats are drawn to hunt in or around recently burnt areas and are also more effective hunters in open habitats. In 2018–2019, we established arrays of camera traps to estimate the abundance of feral cats on Kangaroo Island, South Australia. Much of the island (including five of our seven survey sites) was subsequently burnt in a severe wildfire (December 2019–February 2020). We re‐sampled the sites 3–8 months post‐fire (seven sites) and 11–12 months post‐fire (three sites). At two unburnt sites sampled post‐fire, it was possible to produce density estimates of cats using a spatially explicit capture–recapture approach. Where estimating density was not possible (due to low detections or individual cats not being distinguishable), the number of individuals and percentage of trap nights with detections was compared between the sampling periods. Some low‐level cat control occurred within 2 km of three of the seven arrays (all within the burn scar) within 3 months of the fire. Across the five burnt sites, there was a decline in cat detections post‐fire (including those without post‐fire cat control). At 3–8 months post‐fire, there was, on average, a 57% reduction in the number of individual cats, and a 65% reduction in the number of nights with cat detections, relative to pre‐fire levels. Although cat detections declined following the fire, reduced population sizes of prey species and reduced cover as a result of the fire might still mean that cat predation is a threat to some surviving prey species. Management that reduces feral cat predation pressure on wildlife following wildfire should enhance the likelihood of post‐fire wildlife persistence and recovery. [ABSTRACT FROM AUTHOR]

Historically unprecedented areas of forest habitat have been impacted by fire, as climate change and other anthropogenic disturbances drive increases in fire burned area and severity. Although 88% of Australia's [threatened] land mammals are threatened by inappropriate fire regimes, calculations of animal mortality resulting from specific events have been impeded by knowledge gaps relating to both the direct (first‐order) and long‐term (second‐order) effects of fire on different species. This study addresses the need for a quantified, mechanistic understanding of first‐order effects, presenting an extension of the Fire Research and Modelling Environment (FRaME) to allow prediction of species‐specific mortality. FRaME is demonstrated and tested here by replicating an incident in which a prescribed burn caused 77% mortality of a population of the critically endangered ngwayir (Pseudocheirus occidentalis, Pseudocheiridae). FRaME correctly predicted heavy mortality (62–79%) arising from partial and full‐thickness burns and asphyxiation due to burns in the respiratory tract. Mortality varied with animal fire‐avoidance strategies (p < 0.001) and the thickness of tree hollow walls (r = −0.95, p < 0.001). Although management guidelines specified low intensity fire, mortality had no significant relationship with Byram intensity and larger flames due to 'torching' were most frequent when fire spread was slowest. FRaME modelling predicted that individuals would be impacted by temperatures exceeding 500°C for several minutes. Fire management that is premised on discredited notions of fire behaviour and overly simple models can lead to catastrophic management outcomes such as those documented here. FRaME addresses this need by providing a platform to account for heterogeneous fire behaviour as well as animal behaviour and habitat quality, calculating fire risk to fauna and guiding management that maximizes safe habitat. [ABSTRACT FROM AUTHOR]

An ecological risk assessment, based on life‐history and behavioural attributes of 273 bird taxa, was used to identify which of those taxa are at high risk from negative interactions with offshore wind farms in Australia. The marine area of Australia was divided by state/territory boundaries perpendicular to the coast into eight regions, with Western Australia further divided into north and south, and a Bass Strait region bounded by the Victoria coast and the north coast of Tasmania. These regions were subdivided into coastal, inshore and offshore sub‐regions and a risk summary for all bird taxa occurring in each of these sub‐regions produced. In coastal and inshore sub‐regions of Bass Strait, South Australia and Tasmania, the species with the highest risk scores were Orange‐bellied Parrot Neophema chrysogaster, Furneaux White‐fronted Tern Sterna striata incerta, Swift Parrot Lathamus discolor, Shy Albatross Thalassarche cauta, Far Eastern Curlew Numenius madagascariensis and Anadyr Bar‐tailed Godwit Limosa lapponica anadyrensis. In offshore sub‐regions in southern Australia, the highest risk species were all albatrosses, comprising Northern Royal Diomedea sanfordi, Eastern Antipodean D. antipodensis antipodensis, Gibson's D. antipodensis gibsoni, Wandering D. exulans, Amsterdam D. amsterdamensis and Grey‐headed Albatross T. chrysostoma. Compared to onshore installations, there are logistical challenges to quantifying the potential and realized impacts of offshore wind farms that require different approaches to data collection and analyses. The extensive development of offshore wind farms in the Northern Hemisphere provides examples of best and emerging approaches to quantify and mitigate negative impacts of offshore wind farms that can be applied in an Australian context. Despite differences in the species involved, the same approaches to identifying high‐risk species and to the monitoring and mitigation of negative impacts should be applied in a coordinated, regional‐scale approach to the development of offshore wind farms in Australia. [ABSTRACT FROM AUTHOR]

The article presents the author's views related to the paper "Anomalies in grasstree fire history reconstructions for south-western Australian vegetation," by N.J. Enright, B.B. Lamont and B.P. Miller. The author in the article does not agree with several conclusions provided by the authors in the paper. Several suggestions related to the paper are presented. Several doubts related to the paper are discussed including the relevance of the application of the fire frequency.

Large quantities of dead wood can be generated by disturbances such as wildfires. Dead trees created by disturbances play many critical ecological roles in forest ecosystems globally. The ability of deadwood to serve its ecological roles is contingent, in part, on the length of time trees remain standing following disturbance. Here, we briefly outline the results of a 10‐year study that aimed to quantify the rate of collapse of trees killed in a major wildfire in the wet ash forests of mainland south‐eastern Australia. We also quantified the factors associated with dead tree collapse. Our analyses revealed that 23% of 417 measured trees collapsed between 2011 and 2021. The most parsimonious model of the factors influencing tree collapse revealed a strong effect of diameter; smaller diameter trees were more likely to collapse over the 10 years of our study than larger diameter trees. In addition, trees in small and large patches were more likely to collapse than trees in contiguous forest (where there had been no logging in the surrounding area). If current rates of tree fall are maintained, then many of trees initially measured will have collapsed by 2030. Such losses of dead trees will have major negative effects on key values of ash‐type forests such as biodiversity conservation. [ABSTRACT FROM AUTHOR]

To address uncertainties surrounding the impacts of unprecedented 2019–20 bushfires in south‐eastern Australia, we convened a symposium on field‐measured impacts on biodiversity for the 2020 Ecological Society of Australia conference. Nine presentations covered a range of studies on plant species and communities, and reptiles and mammals. Here, we summarize the presentations and review other field studies from NSW, some of which are currently unpublished. The impacts were extensive, but results also estimated survival rate perhaps higher than first reported in the media. More than half of individual mammal, reptile and threatened rainforest trees may have survived the fire, though small populations remain very vulnerable to second fire in the near future. Comprehensive understanding of the impacts of these fires requires much more field study, and for the results to be interpreted in the context of the broader fire regime. The symposium was an important early step in that understanding. [ABSTRACT FROM AUTHOR]

Discusses an approach to biodiversity monitoring and reporting in the rangelands of Australia. Identification of indicators presented in an analytical framework; List of pressures affecting the conservation status of biodiversity; Resolution to planning issues concerning the implementation of a monitoring program for rangelands biodiversity.

The response of bees to changing environmental temperatures has implications for pollination in natural and agricultural systems, with rising average temperatures and increased environmental stochasticity predicted to cause pollinator population declines. A growing body of evidence for the role of native bees in crop pollination suggests that understanding the temperatures at which bees are active is important for maintaining agricultural productivity under climate change. This study used two methods to sample bees at strawberry farms in south‐eastern Australia, matching activity observations with microclimate temperature to understand how temperature impacts bee activity. Apart from Apis mellifera (introduced), two native bees were identified, Lasioglossum spp. and Exoneura robusta. Apis mellifera was the most abundant species across all environmental temperatures, and E. robusta the least. Visual and sweep‐netting survey results found activity temperature range was broader for A. mellifera (16.21–41.05°C) than Lasioglossum (16.49–38.91°C) and E. robusta (26–38.82°C). The results suggest that activity temperature varies among bee species, with potential implications for community composition and plant pollination under climate change. [ABSTRACT FROM AUTHOR]

Carnivores have key ecological roles in structuring and regulating ecosystems through their impacts on prey populations. When apex‐ and meso‐predators co‐occur in ecosystems, there is the potential for complex interspecific interactions and trophic dynamics that can affect the composition and functioning of ecological communities. Investigating the diet of sympatric carnivores can allow us to better understand their ecological roles (e.g. potential suppression of herbivores) or impacts (e.g. predation of threatened species). Australia's alpine region provides an ideal system in which to explore spatial and temporal variation in predator and prey interactions, using the dingo (Canis dingo) and invasive red fox (Vulpes vulpes) diet. We examined the diet of dingoes and foxes across three different mountains and seasons in Victoria's alpine region, using macroscopic scat analysis. There was little diet overlap between the two carnivores, with foxes having a broader diet than dingoes. Dingoes primarily consumed larger mammal species, including invasive sambar deer (Cervus unicolor, 44%), and the native common wombat (Vombatus ursinus, 34%), whereas foxes typically consumed smaller mammals, including the native bush rat (Rattus fuscipes, 55%), and the invasive European rabbit (Oryctolagus cuniculus, 15%). Dingoes consumed more than thirty times the volume of large invasive mammals (predominantly sambar deer) than did foxes. Foxes consumed close to 15 times as many critical weight range individuals per scat than dingoes. Only one threatened critical weight range mammal species was identified within scats, the broad‐toothed rat (Mastacomys fuscus), found within five fox scats. Our results suggest that the introduction of novel prey may alter predator–predator interactions by causing a reduction in the dietary overlap. Therefore, in the context of integrated wildlife management and biodiversity conservation, any control of novel, invasive prey populations needs to consider possible flow on effects to apex‐ and meso‐predator diets and potential secondary impacts on native prey. [ABSTRACT FROM AUTHOR]

Human intervention through damming, diversion and extraction of water resources has created regulated dryland river systems. As a result, connectivity between river channels and floodplain wetlands has diminished. Wetland function is fundamentally linked to water availability: flooding exchanges water, nutrients, sediments and biota with the floodplain. Water allocation for environmental flows may mitigate wetland degradation following river regulation by improving hydrological connectivity between rivers and floodplain wetlands. We report the results (2014–15 to 2018–19) of a vegetation monitoring program in the Macquarie Marshes in north western New South Wales. As part of the long‐term program, we monitored semi‐permanent wetland (Water Couch (Paspalum distichum) grassland or sedgeland dominated) and River Red Gum (Eucalyptus camaldulensis) forest/woodland communities along with environmental and water resource availability predictors. During the five‐year period, we found linear and nonlinear responses of functional group abundance and species richness to the water year and to time since last inundation. We also found differences in species assemblages in response to the flow and flooding regime, particularly water year and inundation duration. These results indicated that wetlands continued to express dry and wet phase responses. We also observed a depressed response to the large 2016–17 flood event by a subset of semi‐permanent wetland sites that had not been inundated in 3 years, compared with sites that were more recently inundated. This result indicated that environmental water management, along with protection of natural inundation events, may improve the resilience of floodplain wetlands: increased hydrological connectivity may promote a stronger wetland response when floods occur. Our results indicate that inundation, in part comprised of managed environmental flows, is a primary driver of species assemblage and functional group representation in semi‐arid floodplain wetlands. [ABSTRACT FROM AUTHOR]

Serotinous plants that both release seed and resprout after fire are thought to be resistant to wildfires within the range of intensities that have been experienced up until now. However, the frequency and scale of intense wildfires is increasing under climate change. We studied annual flowering and fruit‐set in a large population of Banksia spinulosa plants in south‐eastern Australia from the early 1990s to 2006. The results led us to predict that there would be little recruitment from seedlings after the next fire but good resprouting from very long‐lived lignotubers. Our study population burned in the widespread, high‐intensity wildfires of December 2019, providing an opportunity to test the hypothesis. Most above‐ground stems and cones were reduced to ash, and only 15 cones (on 10 plants) remained after the fire. We found no seedlings in the 0.3 ha site that had initially contained over 350 adult plants. Little natural mortality had been observed pre‐fire, but by 5 months after the fire, nearly 25% of lignotubers had failed to resprout. We conclude that even common and widespread resprouting species will suffer population decline and reduced genetic diversity as high‐intensity fires become more extensive and frequent. [ABSTRACT FROM AUTHOR]

Invasive mammalian predators are implicated in the ongoing decline of a suite of fauna and continue to be a major cause of human–wildlife conflict globally. Lethal control of invasive predators is a common management strategy; however, the use of activity indices to measure management effectiveness is problematic. Non‐invasive genetic sampling may be a viable alternative approach to monitoring as individual animals can be identified, allowing for direct estimation of population density through newly developed spatially explicit capture–recapture techniques. Here we compare inferences derived from a basic activity index (number of scats per survey) and genetic sampling of scats within a before–after control–impact design to evaluate the effectiveness of a lethal control programme targeting red foxes (Vulpes vulpes) in south‐eastern Australia. The activity index was highly variable through time and suggested the baiting programme reduced fox activity on the treatment transect relative to changes on the non‐treatment transect. In contrast, genetic sampling and spatially explicit capture–recapture analysis suggested fox density varied little throughout the study, with any changes unable to be attributed to the baiting programme. Additionally, genetic sampling confirmed many individuals persisted through 7 months of baiting. These contrasting results may be partially explained by changes in scat detectability due to seasonal changes in behaviour and the disproportionate contribution of some individuals to scat counts. Our pre‐baiting density estimate of 0.28 foxes km2 (95% CI: 0.22–0.38) was lower than expected given the high productivity, abundant prey species and lack of larger predators in the study region. Our results highlight the need for cautious interpretation of activity indices and demonstrates the value of incorporating recent methodological and statistical advances when evaluating lethal control programmes. [ABSTRACT FROM AUTHOR]

Carrion is an ubiquitous resource that drives the dynamics of scavenger populations and shapes the structure and composition of their communities. Corvids (Family: Corvidae) are among the most common scavengers globally, facilitating carcass discovery by other species and contributing to carcass biomass removal. Here, we examine how environmental factors influence corvid scavenging dynamics in an arid region of Central Australia. Specifically, we investigate how habitat, season and a major flood event affect corvid discovery and visitation time, and group size around carcass sites. To do so, we used data collected from camera traps monitoring 80 experimentally positioned red kangaroo (Osphranter rufus) carcasses stratified across closed and open habitats, spring and winter seasons, and before and after a flood event. Corvids took longer to discover carcasses in closed compared to open habitats, but habitat did not affect how long corvids spent visiting carcasses, or corvid group size. Corvids discovered carcasses faster in winter compared to spring and in post‐flood compared with the pre‐flood periods, and season and flood interacted to influence both corvid visitation time and group size. Our results reflect a complex interplay between temperature, the extreme boom and bust cyclicity of the study region and changing corvid activity and abundance in the local study area. We identify environmental factors as key determinants of corvid scavenging dynamics and provide the first detailed description of scavenging by corvids in the arid zone of Australia. [ABSTRACT FROM AUTHOR]

Wind dispersal is considered to be a potentially important mode of spread for parthenium weed (Parthenium hysterophorus L.), an invasive Asteraceae herb of worldwide significance. However, empirical evidence of the role of wind dispersal on the seeds (achenes) of parthenium weed in natural landscapes is lacking. The results of a simulation study undertaken at a wind tunnel facility, Australia, indicated that the dispersal distance of parthenium weed achenes is largely determined by wind velocity (109–131% increase in distance where wind velocity is doubled) and plant release height (75–80% increase when release height is doubled). Glasshouse harvested achenes released from 1 m in height could travel up to 2 m under a 2 m s−1 wind velocity, with the majority of achenes reaching more than 1 m. Smaller‐sized achenes travelled 5% further than larger‐sized achenes. The terminal velocity was calculated to be 1.256 ± 0.006 m s−1, indicating a moderate wind dispersal ability for the weed. A complementary field study in Southeast Queensland, Australia, indicated that the cumulative wind velocity and wind direction, instead of the mean wind velocity, determined the direction of dispersal of the achenes. Further post‐dispersal surveys suggested the number of achenes outside of a standing population declined rapidly as distance from the population increased. Most achenes were dispersed less than 2 m from their parent plant, while the maximum distance achieved was less than 5 m under natural conditions in North Queensland. In conclusion, the natural wind dispersal of parthenium weed consists of small, but measurable increments each year, thus contributing to the weed proliferation and spread at the landscape scale level. [ABSTRACT FROM AUTHOR]

Our understanding of the habitat needs of grassland fauna is often incomplete because of their cryptic behaviour. This presents a barrier to identifying important habitat attributes, whether these change at different spatial scales, and how this informs management decisions. Here, we use a critically endangered bird, the Plains‐wanderer (Pedionomus torquatus, Pedionomidae), as an exemplar of the challenge of managing grasslands for cryptic species. Until now, almost all ecological knowledge of Plains‐wanderers has come from the detection of nocturnally roosting individuals and habitat assessments at fine‐scales that indicate open swards are preferred habitat. We GPS‐tracked 13 adult Plains‐wanderers to better understand diurnal habitat utilization in native grasslands of south‐eastern Australia. Using these data, we assessed whether Plains‐wanderers select for different habitat attributes during the day and night, and whether this varied according to spatial scale. At the fine‐scale (< 1 ha), daytime foraging occurred in denser swards than those of nocturnal roosting sites. At the patch‐scale (1–50 ha), Plains‐wanderers selected for denser vegetation, with higher grass and lichen cover, whilst avoiding areas where structure was impacted by a high exotic plant cover. Plains‐wanderers did not select habitat based on grassland type at the landscape‐scale (>100 ha). We demonstrate that Plains‐wanderers require grasslands with both open and denser swards to support foraging and roosting. In doing so, we address the biases associated with habitat assessments based on roost‐only locations and extend known habitat associations critical to the successful management of the species. Our findings highlight that a precautionary approach to the classification of habitat requirements is warranted when uncertainty around habitat use of cryptic grassland fauna exists. [ABSTRACT FROM AUTHOR]

Recent landscape‐scale wildfires in eastern Australia have made apparent the need for a greater understanding of the flammability dynamics of forested ecosystems. Fire severity is a measure of the impact of a fire on vegetation, but little is known about the landscape‐scale response of the fire‐prone dry sclerophyll forests of eastern Australia to different levels of fire severity. Species in these forests have multiple responses to fire, which can be dependent on the fire severity. In this study, we aimed to determine the effect of fire severity on the vegetation structure, and therefore flammability, of these forests. We addressed two hypotheses that 1) High severity fire would result in a denser understory than low severity fire after 5 years and that 2) High severity fire would reduce the vertical separation between understory and canopy after 5 years. Field surveys of 38 forest sites with differing fire severity but standardised time since fire and forest type, in Sydney region of New South Wales, Australia, were used to test these hypotheses. We found lower canopy cover and greater understory cover (0.5–4 m height) after high severity fire compared with sites which burnt at low severity. Vertical separation was less between the canopy and understory at sites after high severity fire than after low severity fire. The greater quantity of understory fuel and greater vertical continuity in fuel structure observed suggests a potential increase in forest flammability after high severity fire compared with lower severity fires in these forest types. [ABSTRACT FROM AUTHOR]

Temporal partitioning between ecologically similar species facilitates co‐occurrence and can influence the structure of mammalian assemblages. We studied diel activity patterns of two sympatric forest‐dwelling wallabies, the red‐legged pademelon (Thylogale stigmatica) and red‐necked pademelon (Thylogale thetis) in eastern Australia to better understand spatiotemporal partitioning between these closely related macropods. Temporally, both species displayed strongly crepuscular activity patterns typical of many macropod species; however, compared with T. thetis, T. stigmatica was less active during evening twilight and more active in the period prior to dawn. Spatially, T. stigmatica used dense forest cover exclusively throughout the 24‐hour cycle, while T. thetis divided its habitat spatiotemporally, spending the diurnal period under forest cover and the nocturnal period on pasture beyond the forest edge. In practical terms, this meant that T. stigmatica and T. thetis were fully spatially segregated at night, during the period they would be likely to do most of their foraging. We propose that the spatiotemporal partitioning observed is niche partitioning, and provides a mechanism for the co‐occurrence of these closely related species. [ABSTRACT FROM AUTHOR]

Native to South Africa, fireweed (Senecio madagascariensis Poiret; Asteraceae) is an annual or short‐lived perennial herb that is highly invasive in Australia, where it is a target for biological control. Preliminary research indicates that fireweed may be undergoing adaptive changes along its invasion gradient in Australia. Changes, such as a shift in plant chemical defence, may influence fireweed's interaction with specialist insect herbivores, and hence the efficacy of a biocontrol program. As the testing of biocontrol candidates is a rigorous and lengthy process, confirmation of fireweed's susceptibility to insect attack may assist in fast tracking candidate suitability, where changes in plant defensive chemistry are found. In a large experimental field study in fireweed's native range, we compared the susceptibility of Australian and South African populations to insect natural enemy attack (in terms of plant biomass, insect richness and composition). Simultaneously, we assessed the variation in plant pyrrolizidine alkaloid concentrations and composition to rationalise any differences in natural enemy attack between populations. We found no significant differences in plant biomass across fireweed populations, despite significantly higher alkaloid concentrations in Australian populations. The composition of the endophagous (specialist) insect herbivore assemblage was related to alkaloid composition, but there were only minor differences in the assemblage between Australian and South African fireweed populations. Moreover, we found no significant differences in the abundance, richness or Shannon diversity indices of endophagous or ectophagous (generalist) insect herbivores between Australian and South African fireweed populations. Our results suggest that despite variations in chemical defence, Australian fireweed populations displayed neither reduced nor increased susceptibility to specialist insect herbivore attack, supporting the notion that if host‐specific biocontrol agents are released, their impact in Australia is unlikely to be influenced by any changes in plant chemical defence. [ABSTRACT FROM AUTHOR]

Species endemic to high elevations are predicted to see declines in their suitable habitat under future global climate change, even in protected or little disturbed areas. However, such risks are often not included in conservation assessments, especially when appropriate models to predict climate change impacts are not available. Here, we use species distribution models to explore the likely impacts of climate change and recent megafires on the status of two high‐elevation cloud forest‐centred lizards from Australia that were listed as Least Concern in a recent (2017) IUCN Red List assessment of Australian reptiles. We found both species (Harrisoniascincus zia and Silvascincus tryoni) are predicted to lose all suitable habitat by 2050, under 'optimistic' future climate projections. We also found that 52.34–48.5% of H. zia modelled suitable habitat was potentially affected by recent and unprecedented megafires in eastern Australia, while only 0.02–0% of S. tryoni habitat was affected. Our results support upgrading the IUCN Red Listings of H. zia and S. tryoni to vulnerable and endangered, respectively. Our data also highlight an alarming paucity in the number of verified records for these species over the last decade, at precisely the time when these records are becoming critical to testing and validating predictions of declines. The next decade looms as a critical period to establish baseline data sets on the distribution and genetic diversity of these high‐elevation taxa. For reasonably visible and easily identifiable species such as these skinks, citizen science approaches may offer a key path to addressing this challenge. [ABSTRACT FROM AUTHOR]

Long‐term studies are required to reveal responses by long‐lived, top‐order predator populations to ongoing seasonal fluctuations. However, such investigations are rare in the Australian context. Between 2009 and 2019, the breeding density and productivity of an arid and a mesic wedge‐tailed eagle Aquila audax population, each occupying an area of 2800 km2, were compared (11–98 pairs monitored annually). Breeding pairs spaced themselves evenly in both study areas, with no significant difference between the average arid zone nearest‐neighbour distance of 5.32 ± 1.98 km (n = 44) and that determined for the mesic zone (4.88 ± 2.32 km, n = 54). This similarity in spacing suggests a maximum average density is tolerated by these territorial raptors. By contrast, annual breeding success (proportion of pairs fledging young) and productivity (fledged young per pair) differed significantly between the two populations, with rainfall (but not temperature) influencing reproduction. In the arid zone, the proportion of successful pairs per occupied breeding home range was consistently low each year (mean = 12 ± 7% fledged broods per pair, range 0–26%) and positively correlated with annual rainfall. In the mesic zone, it was consistently high each year (mean = 69 ± 9%, range 57–91%) and not significantly correlated with annual rainfall. Overall productivity figures showed similar differences, with 0.13 and 0.77 fledglings per pair per year for arid (n = 9 years) and mesic (n = 11 years) eagles, respectively. Such low arid zone productivity, the lowest ever recorded for the species, could have long‐term implications in the face of the increased frequency of extreme weather events. That breeding density can be independent of climatic factors provides new insight into the way a large Aquila species integrates with Australia's predominantly arid environment. This study provides an important baseline data set for continued research on long‐term occupancy and productivity trends. [ABSTRACT FROM AUTHOR]

Length–mass relationships for macroinvertebrates are used in many ecological studies; however, few length–mass relationships are available for Australian freshwater macroinvertebrates. In this study, we generated 22 new length–mass relationships from 2148 specimens spread across four orders, nine families, three subfamilies, 12 genera and two species. We also qualitatively compare our length–mass equations with others from Australia, New Zealand, North America and Europe. [ABSTRACT FROM AUTHOR]

The European honeybee Apis mellifera is a highly successful, abundant species and has been introduced into habitats across the globe. As a supergeneralist species, the European honeybee has the potential to disrupt pollination networks, especially in Australia, whose flora and fauna have co‐evolved for millions of years. The role of honeybees in pollination networks in Australia has been little explored and has never been characterised in urban areas, which may favour this exotic species due to the proliferation of similarly exotic plant species which this hyper‐generalist can utilise, unlike many native bee taxa. Here, we use a bipartite network approach to compare the roles, in terms of species‐level properties, of honeybees with native bee taxa in bee‐flower ('pollination') networks in an urbanised biodiversity hotspot. We also assessed whether the abundance of honeybees influences overall network structure. Pollination networks were created from surveys across seven residential gardens and seven urban native vegetation remnants conducted monthly during the spring‐summer period over two years. There were consistent differences in species‐level properties between bee taxa, with honeybees often differing from all other native bees. Honeybees had significant impacts on network properties, being associated with higher nestedness, extinction slopes of plants, functional complementarity and niche overlap (year two), as well as lower weighted connectance and generalisation. These associations all are indicative that competition is occurring between the introduced honeybee and the native bee taxa in bee‐flower networks. In conclusion, the introduced honeybee occupies a dominant, distinct position in bee‐flower networks in urban habitats in the southwest Western Australian biodiversity hotspot and has a major, potentially disruptive, influence on plant‐pollinator network properties in these areas. [ABSTRACT FROM AUTHOR]

There has been concern globally about the impacts of wildfires on lives, property and biodiversity. Mechanical thinning has been proposed as a way to reduce fire severity. However, its effectiveness appears to vary between regions and ecosystems. Here, we sought to answer the question: Does thinning reduce the severity of wildfire in managed eucalypt forests? We did this by completing an empirical study of the factors affecting two levels of fire severity – crown burn and crown burn/crown scorch in lowland and wet/damp forest burned in 2019‐2020 in East Gippsland, Australia. We found complex interactions between thinning, forest type and time since the last major disturbance in the best‐fitting models for crown burn and crown burn/crown scorch. The probability of a crown burn was higher in younger stands of thinned forest than in unthinned forest. Crown burn risk in thinned forest was characterised by an inverse relationship with increasing time since the last disturbance; there were no such effects in unthinned forest. We found that the probability of crown burn/crown scorch increased with time since last disturbance in both thinned and unthinned lowland forest. The probability of crown burn/crown scorch also increased over time in wet/damp forest, but the patterns were different between unthinned and thinned stands. Risk of crown burn/crown scorch was lower in young thinned forest relative to unthinned forest, but this pattern reversed with increasing time since the last disturbance. Our analyses showed the efficacy of thinning was variable, depending on fire severity, type of forest targeted for management and the age of that forest (as reflected by the time since the last major disturbance). Therefore, thinning interventions to mitigate fire severity should not be implemented without consideration of these factors and are unlikely to be a viable management option in many circumstances. This is because, in some cases, thinning can lead to elevated fire severity (e.g. soon after thinning for crown burn and in older forests for crown burn/crown scorch) and hence have opposite effects to those intended from such activities. [ABSTRACT FROM AUTHOR]

Overcoming low breeding success is a major challenge for reversing population decline in threatened species. High nest predation rates are a common cause of low productivity in birds, but implementing evidence‐based management actions to reduce nest predation is challenging. Targeted breeding management requires a good understanding of where threatened species breed, the identity and distribution of nest predator species and the impact of these nest predators on breeding success. For rare and nomadic species, this information is hard to come by. The breeding success of regent honeyeater Anthochaera phrygia has declined over recent decades, and nest predation is the primary cause of breeding failure. We conducted point‐count surveys of nine avian and three mammalian nest predator species across 80% of the regent honeyeater's contemporary breeding area in south eastern Australia. We used occupancy models to determine the presence of predator species at survey sites and spatial models to predict predator abundance and species richness across the breeding area. We incorporated predator predictions for regent honeyeater nest locations into nest fate and daily nest survival models. Predator abundance was correlated positively with tree hollow abundance and proximity to water and negatively with shrub cover. Regent honeyeater nest success showed no significant relationship with predator abundance or predator species richness. Given how abundant and widespread avian and mammalian nest predators were throughout the breeding area, improving regent honeyeater nest success is likely to require implementation of simultaneous nest protection measures to avoid potential compensatory nest predation. Further research is required to better understand the relationship between nest predator abundance and regent honeyeater nest success. [ABSTRACT FROM AUTHOR]