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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]

Integrated distribution models (IDMs) predict where species might occur using data from multiple sources, a technique thought to be especially useful when data from any individual source are scarce. Recent advances allow us to fit such models with latent terms to account for dependence within and between data sources, but they are computationally challenging to fit.We propose a fast new methodology for fitting integrated distribution models using presence/absence and presence‐only data, via a spatial random effects approach combined with automatic differentiation. We have written an R package (called scampr) for straightforward implementation of our approach.We use simulation to demonstrate that our approach has comparable performance to INLA—a common framework for fitting IDMs—but with computation times up to an order of magnitude faster. We also use simulation to look at when IDMs can be expected to outperform models fitted to a single data source, and find that the amount of benefit gained from using an IDM is a function of the relative amount of additional information available from incorporating a second data source into the model. We apply our method to predict 29 plant species in NSW, Australia, and find particular benefit in predictive performance when data from a single source are scarce and when compared to models for presence‐only data.Our faster methods of fitting IDMs make it feasible to more deeply explore the model space (e.g. comparing different ways to model latent terms), and in future work, to consider extensions to more complex models, for example the multi‐species setting. [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]

Suppressing expert knowledge can hide environmentally damaging practices and policies from public scrutiny. We surveyed ecologists and conservation scientists from universities, government, and industry across Australia to understand the prevalence and consequences of suppressing science communication. Government (34%) and industry (30%) respondents reported higher rates of undue interference by employers than did university respondents (5%). Internal communications (29%) and media (28%) were curtailed most, followed by journal articles (11%), and presentations (12%). When university and industry researchers avoided public commentary, this was mainly for fear of media misrepresentation, while government employees were most often constrained by senior management and workplace policy. One third of respondents reported personal suffering related to suppression, including job losses and deteriorating mental health. Substantial reforms are needed, including to codes of practice, and governance of environmental assessments and research, so that scientific advice can be reported openly, in a timely manner and free from interference. [ABSTRACT FROM AUTHOR]

Fires change ecosystem composition and influence species extinction risk, yet information on the impact of fire on biodiversity is scant. The bushfires in southeastern Australia during the summer of 2019/20 were unprecedented in their extent and intensity, and postfire management decisions have been hindered by a lack of knowledge of the impact of fires on biodiversity. We examine the short‐term persistence of frog species across southeastern Australia after these fires using records of calling frogs from the national citizen science project FrogID. We demonstrate widespread short‐term persistence of frog species. Sixty‐six frog species were detected in the firegrounds before the fire, and within 125 days postfire, 45 of these were detected. All 33 frog species with more than five records that were detected in the months of December–March prefire were detected postfire. While the short‐term postfire persistence of so many frog species is a positive result, the population‐level and longer‐term consequences of the fires remain unknown, as does the ability of frogs to persist with the changing fire regimes predicted as a consequence of global climate change. We illustrate the value of citizen science in collecting large‐scale and rapid observations in response to increasing anthropogenically‐driven ecological events. [ABSTRACT FROM AUTHOR]

Mouse plagues are a regular feature of grain‐growing regions, particularly in southern and eastern Australia, yet it is not clear what role various ecological processes play in the eruptive dynamics generating these outbreaks.This research was designed to assess the impact of adding food, water, and cover in all combinations on breeding performance, abundance, and survival of mouse populations on a typical cereal growing farm in northwestern Victoria.Supplementary food, water, and cover were applied in a 2 × 2 × 2 factorial design to 240 m sections of internal fence lines between wheat or barley crops and stubble/pasture fields over an 11‐month period to assess the impact on mouse populations.We confirmed that mice were eating the additional food and were accessing the water provided. We did not generate an outbreak of mice, but there were some significant effects from the experimental treatments. Additional food increased population size twofold and improved apparent survival. Both water and cover improved breeding performance. Food and cover increased apparent survival.Our findings confirm that access to food, water, and cover are necessary for outbreaks, but are not sufficient. There remain additional factors that are important in generating mouse plagues, particularly in a climatically variable agricultural environment. [ABSTRACT FROM AUTHOR]

Echidnas are egg‐laying mammals found across Australia, and in Tasmania they hibernate, resulting in a most unusual mating system: males enter hibernation in late summer–early autumn and arouse in late autumn–early winter to mate, although females are still hibernating. Groups of males compete for matings and both males and females mate with multiple partners. Females that mate early return to hibernation even when pregnant, and males continue to mate with pregnant females. We asked to what extent can the bizarre combination of behavioural and physiological features that characterize reproduction of Tasmanian echidnas be attributed to their phylogeny, and how much is a consequence of their ecology?To understand the interaction between energetics and the echidna mating system in determining the timing of echidna hibernation, we analysed data from an 18‐year study of a wild population of Tasmanian echidnas (Tachyglossus aculeatus setosus)Males in best condition arouse earliest and seek out suitable females, and females that mate early in the mating season re‐enter hibernation while pregnant.Competition between males drives early mating and while mating with males in the best condition could be advantageous for females and their young, egg‐laying in winter is potentially disadvantageous, and post‐mating hibernation by females is a means of delaying hatching of young until environmental conditions are more favourable. This post‐mating hibernation by females is usually disrupted by males which mate with them although they are already pregnant.Comparisons with other echidna populations suggest that a decreased activity period due to hibernation has not increased male–male competition.Similar competition between groups of males for access to females is seen in chlamyphorid armadillos, which occupy a similar ecological niche to echidnas. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

In the face of massive human impacts upon the environment, a prevailing attitude among Australian ecologists seems to have become one of pessimism. The essay explores the consequences of this stance. Pessimism arises understandably from personal values favouring care for the natural world under conditions of rapid global change. Expression of such values is in no way illegitimate; pessimism is as justifiable a perspective as is optimism when interpreting ecology. Examples are mentioned of areas of Australian ecology where pessimism does not predominate, and where the ecological changes being wrought by the Anthropocene are accepted. But, the predominance of gloom can cause ecologists to flirt with exaggeration and with misanthropy, and perversely it can cause them to strive to prevent ecological change even though the discipline is rooted in the reality of flux. Most profoundly, it causes many citizens to switch off: gloom has limited capacity to motivate, whereas hope is the elixir of action. Because of predominant negativity, we risk losing the confidence of society. The solution is for the discipline to develop more diverse strands of interpretation, characterized by more equal doses of acceptance and hope. By balancing dejection, ecology may achieve the efficacy in debate and decision-making that it warrants in these challenging times. [ABSTRACT FROM AUTHOR]

Across their range, mangroves are responding to coastal environmental change. However, separating the influence of human activities from natural events and processes (including that associated with climatic fluctuation) is often difficult. In the Gulf of Carpentaria, northern Australia (Leichhardt, Nicholson, Mornington Inlet, and Flinders River catchments), changes in mangroves are assumed to be the result of natural drivers as human impacts are minimal. By comparing classifications from time series of Landsat sensor data for the period 1987-2014, mangroves were observed to have extended seawards by up to 1.9 km (perpendicular to the coastline), with inland intrusion occurring along many of the rivers and rivulets in the tidal reaches. Seaward expansion was particularly evident near the mouth of the Leichhardt River, and was associated with peaks in river discharge with Li DAR data indicating distinct structural zones developing following each large rainfall and discharge event. However, along the Gulf coast, and particularly within the Mornington Inlet catchment, the expansion was more gradual and linked to inundation and regular sediment supply through freshwater input. Landward expansion along the Mornington Inlet catchment was attributed to the combined effects of sea level rise and prolonged periods of tidal and freshwater inundation on coastal lowlands. The study concluded that increased amounts of rainfall and associated flooding and sea level rise were responsible for recent seaward and landward extension of mangroves in this region. [ABSTRACT FROM AUTHOR]

We studied how grazing intensity by small and mid-sized ungulate grazers varied with nutritional quality and grass species composition in wet oligotrophic tallgrass savanna of coastal northern Tanzania. Average grazing intensity was low (3-15% by cover), and most grass species were scarcely used by herbivores. Only two grasses, P anicum infestum and D igitaria milanjiana, had nitrogen and phosphorus concentrations that were consistently above the minimum levels (e.g. nitrogen concentrations <7 mg g−1) required by the three commonest grazers, Bohor reedbuck, waterbuck and wildebeest. The best predictors of grazing intensity were cover of P. infestum (the most abundant grass, with a mean cover of 15%) and canopy height of ungrazed vegetation. Models did not contain separate predictors for nutritional quality, presumably because quality varied mainly at the grass species level and therefore was fully represented by the variable 'cover of P . infestum'. Given that the three grazers differed greatly in body size and muzzle width (parameters known to influence nutrient requirements and the ability of grazers to feed selectively at the smallest spatial scale), we expected there to be strong resource partitioning that would be detectable in terms of grazing strategies and feeding sites. However, apart from minor differences in canopy height, greenness and diameter of grazed patches (albeit consistent with our expectations), feeding stations of the three grazers were similar and strongly dominated by P . infestum. We conclude that the low quality of herbage in wet oligotrophic savannas restricts foraging choices, which produces a characteristic yet impoverished grazing community that exhibits only limited resource partitioning. [ABSTRACT FROM AUTHOR]

In this study, systematic variation in tree morphology across a rainfall gradient in Australia's tropical savanna biome and its implications for carbon stocks and dynamics were quantified. The aim was to support efforts to manage fire regimes to increase vegetative carbon stocks as a greenhouse gas mitigation strategy. The height of trees for a given trunk diameter declines with decreasing rainfall from 2000 to 300 mm and increasing dry season length across the Australian savanna biome. It is likely that increasing dry season length is the main driver of this decline rather declining rainfall per se. By taking account of the response of total basal area to rainfall and soil type, stand structure, and tree height and diameter relationships, the carbon stocks in live trees were estimated to decline from about 34 t ha−1 in the wetter savannas to 6 t ha−1 in the drier savannas. These values are broadly consistent with field-based estimates. Because of the declining ratio of height to trunk diameter, trees of a given diameter in drier regions will be more likely to be killed by fires of a given intensity than trees in wetter regions. Thus single fires of given intensity are likely to have a greater proportionate impact on live tree carbon stock in drier savannas, but a much greater absolute impact in wetter savannas due to the greater total carbon stock. Projected decreases in early wet season rainfall under climate change scenarios, despite projections of little change in total precipitation in northern Australia, may lead to decreased carbon stock in live trees through two mechanisms: a reduction in total basal area and decreases in tree height for given trunk diameters. [ABSTRACT FROM AUTHOR]

The basic methods for rehabilitating degraded land left after mining are reasonably well-understood and there are examples across Australia of these being currently implemented. But there are many other situations where further research will be needed to achieve rehabilitation objectives. In addition, a number of mines are yet to embark on any sustained program of rehabilitation and there is a disappointing number of cases of mines ceasing operations before rehabilitation is completed leaving sites in a badly degraded state. Overall there appear to be surprisingly few examples in Australia of post- mining rehabilitation that has reached a successful conclusion. In part, this may be simply a matter of time and the problem will be resolved as more mines reach the end of their working lives. But there is an apparent trend for mines to be placed into 'care and maintenance' or sold to other entities, to avoid the costs of rehabilitation. Thus, we are concerned there is a widening gap between what should be possible and what is being done in practice. We review some of the experiences of rehabilitating post-mining landscapes in Australia and conclude that problems have arisen because of (i) the inherently difficult task of restoring ecosystems at highly modified mine sites, (ii) institutional and management weaknesses and (iii) loose regulatory frameworks that allow a high level of company self-regulation. A key problem is that the importance of rehabilitation appears to rank below that of production in the minds of many mine managers and is not accorded the level of priority that the community expects. The scale of the mining industry and its capacity to cause environmental damage means that there is a need to improve the way mine rehabilitation is currently undertaken. We suggest that this might be achieved by improving research programs as well as better institutional and regulatory arrangements. The present situation represents a major ecological and financial risk to the nation as a whole and regulatory authorities need to develop more rigorous approaches to ensure effective rehabilitation standards are achieved. [ABSTRACT FROM AUTHOR]

In this study we assessed the water transport strategies and the abundance of alien and native tree species at a regional scale in Córdoba Mountains, Central Argentina. The aims of this study were: (i) to analyse whether alien and native tree species show divergent water transport strategies; and (ii) to explore whether species abundances of alien and natives are associated with specific trait attributes. Eight alien species and 12 native species were recorded in 50 complete vascular plant vegetation relevés. Water transport strategies were assessed through the following functional traits: minimum leaf water potential, potential water content of wood, effective leaf area, leaf area per sapwood area and wood density. Also, resource use strategies were assessed throughout the measurement of specific leaf area. We found that alien species had a higher efficiency in water transport (i.e. higher minimum leaf water potential and lower wood density values) and faster resource acquisition and use (higher specific leaf area values) than native species. We did not find evidence suggesting that the relative abundance of species was associated to water transport strategies and faster resource acquisition and use. Alien species seem to differ from natives in specific functional attributes that are absent in the resident community and might allow aliens to use more resources and at a higher rate than native species. Finally, our results show the potential of a trait-based predictive framework for alien species, and the possible effects on ecosystem functions. [ABSTRACT FROM AUTHOR]

Accurate determination of the population density of key focal species is necessary for monitoring the success of management programs and ecosystem health across a wide range of contexts. Unfortunately, many key taxa are visually cryptic and thus difficult to count using traditional observation-based techniques. Bell miners ( M anorina melanophrys), are just such a species. They are widespread throughout south-eastern Australia, yet they are critical to monitor given their association and potential causal link to spreading vegetative dieback in this region. A new passive acoustic monitoring technique was trialled by testing its ability to determine population densities of bell miner colonies via counting the distinctive 'tink' vocalization of this species. This call was given at a constant rate per individual, and at a common amplitude across 10 colonies throughout the entire geographic range of the species. Theoretical sound transmission and playback trials through typical habitat determined that any bird within a 50-m radius of the recorders used would be louder than 70 dB, enabling this threshold amplitude to be used to determine the number of birds in a 50 m radius of the recorder. Field trials of the acoustic protocol versus human observers using traditional visual surveys found that passive acoustic monitoring was able to detect more individuals, using a less expensive protocol that drastically reduced the need for observer training or expertise. Sound therefore offers a reliable method for determining the density of this vocal, but visually cryptic species. We present methods for calibrating recording devices and detecting calls louder than species-specific thresholds using readily available freeware, enabling our methods to be easily adapted to census a variety of acoustically distinctive species, offering a more effective, yet lower cost and in our case more efficient census technique for surveying difficult species. [ABSTRACT FROM AUTHOR]