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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]

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]

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]

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]

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]

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]

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]

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]

This paper documents the effects of fire on grass-layer invertebrates in tropical savannas of the Kimberley region of north-western Australia, in the context of resource availability for consumers. Inappropriate fire regimes have been identified as a factor threatening a number of vertebrate groups, including small mammals, across northern Australia, and a possible mechanism might be through the effects of individual fires or fire regimes on food availability. We test for a fire effect on grass-layer invertebrate resources, which may affect insectivorous savanna vertebrates. Wet season sweep-net invertebrate samples were taken in two tropical savanna habitats, with contrasting laterite and sandstone substrates, in 2008, 2009 and 2010. Sites were stratified by post-fire interval to analyse invertebrate successional change after fire. In addition, experimental burns were implemented in 2010 to investigate immediate post-fire invertebrate responses. Total invertebrate numbers declined by 80-90% immediately (1 week) following fire, reflecting the loss of grass-layer habitat. Of the commonly sampled invertebrate groups, Araneae, Coleoptera, Hempitera, Lepidoptera, Formicidae and Diptera were all reduced in numbers immediately post-fire, whereas Orthoptera showed no immediate post-fire decline. Invertebrate numbers were rapidly restored to pre-fire levels by the first wet season after fire, and no detectible change was observed in numbers or composition from 1 to 3-4 years post-fire (the longest post-fire interval available). This suggests that the effects of individual fires on grass-layer invertebrates are very short-lived. Such short-lived post-fire responses among grass-layer invertebrates, plus evidence that most ground-layer invertebrate groups are fire-resilient, suggest that food resource limitation is not a tenable explanation for fire-related declines among insectivorous savanna vertebrates. However, wet season burning could result in significant invertebrate resource depletion in highly flammable habitats ( Triodia and Sorghum spp. savannas) during important vertebrate breeding/recruitment periods, if burning is extensive and if grass-layer invertebrates do not recover within a few weeks of fire. [ABSTRACT FROM AUTHOR]

This paper examines the economic potential for fire management to provide offsets to carbon markets in the savannas of northern Australia. Long-term field trials in Australia's savannas have quantified greenhouse gas (GHG) emissions abatement resulting from improved fire management. However, little is known about the economic potential of fire management projects or the locations where projects might be economically viable for providing GHG offsets. A benefit-cost analysis of fire management for GHG offsets is presented here, which includes spatially explicit estimates for GHG abatement under three assumptions of management efficacy (conservative, empirically based, upper potential). The total supply of GHG abatement is estimated under different prices and management efficacy assumptions, and areas that pass the benefit-cost analysis are identified. At the Australian Government's carbon price of A$23 per metric tonne of carbon dioxide equivalents (CO2-e), fire management would be economically viable across 51 million hectares, all within the higher monsoonal rainfall regions of northern Australia, abating 1.6 million tonnes of CO2-e per year. These estimates suggest that fire management projects can contribute to GHG abatement targets and be financially viable across large areas of northern Australia. Additional benefits are anticipated from these projects for biodiversity conservation, livelihoods for indigenous Australians and economic development in remote regions. [ABSTRACT FROM AUTHOR]

Tropical savannas are the world's most fire-prone biome, and savanna biotas are generally well adapted to frequent fire. However, in northern Australia there are concerns that recent increases in the frequency and extent of high-intensity fires are causing substantial declines in regional biodiversity values. In this paper we use two well-studied and contrasting faunal groups, ants and small mammals, as case studies for reviewing faunal responses to fire in Australian savannas. The Australian savanna ant fauna is dominated by arid-adapted taxa that are highly resilient to frequent fire and are not considered to be threatened by prevailing fire regimes. Indeed, frequent fire promotes ant diversity because it maintains an open habit that makes the dominant arid-adapted taxa feel at home. Long-term fire exclusion reduces ant diversity due to a marked decline in arid-adapted taxa, and favours highly generalized, more shade-tolerant taxa. In contrast, many small mammal species of high conservation value are highly sensitive to frequent fire, and there are widespread concerns that their populations are threatened by current fire management. Many of the species have shown dramatic population declines over recent decades, and, although the causes are poorly understood, there is little doubt that fire is an important contributing factor. It is likely that fire is acting synergistically with other underlying causes of decline, particularly predation by feral cats. The overall resilience of most savanna animal species in relation to frequent fire suggests that they are secure under all but the most extreme fire regimes. However, it is clear that more fire-sensitive groups such as small mammals need special fire management attention. This needs to involve less frequent and finer-scale burning, along with the protection of some large, infrequently burnt source areas. [ABSTRACT FROM AUTHOR]

Species relocation programmes are increasingly performed with the intention of establishing a self-sustaining population of threatened or declining native species. However, the use of experimental quantitative approaches in species relocation programmes is still relatively uncommon, despite a number of international studies recommending clear guidelines and standards. This paper evaluates species relocation programmes conducted within Australia to assess how programmes performed in relation to such standards. The search techniques identified 54 species relocation programmes, the majority of which were reintroductions (52%) and supplementations (30%). Only 25 (46%) of the species relocation programmes claimed success, with a lack of effective predator control recognized as contributing to the failure of 14 programmes. There was considerable variation in the quality of species relocation programmes in relation to key features such as whether the programme integrated experimental approaches with testable hypotheses, whether there were explicit statements of criteria for success, whether suitable habitat was identified for the release site and whether long-term monitoring was conducted. We propose guidelines to improve scientific rigour and success rates of species relocation programmes. [ABSTRACT FROM AUTHOR]

Fallen branches are a substantial component of coarse woody debris and a key ecological resource. The depletion of stocks of coarse woody debris since European settlement has contributed to the degradation of Australian grassy box woodlands, including the loss of biodiversity. Restoration options for remnant woodlands include the augmentation of coarse woody debris stocks. However, the extensive modification of grassy box woodlands has left few reference sites for establishing benchmarks to guide such restoration. In this paper we demonstrate a method for predicting fallen branch debris loads in the absence of reference sites, using data from a yellow box-red gum woodland. Our methodology is in two stages: first, the total volume of branch debris under individual trees was modelled; and second, these models were applied to groups of trees to predict stand-level loads of fallen branch debris. Although the models were developed for yellow box-red gum woodlands, the methodology would be applicable to other communities that lack reference sites. Predicted benchmark loads of fallen branch debris for yellow box-red gum woodland were between 7.0 m ha and 11.9 m ha. Large senescing trees contributed the bulk of fallen branch debris. Model predictions indicated a 100-cm diameter at breast height (dbh) tree was 10 times more likely to produce debris than a 50-cm dbh tree, and if debris was present a 100-cm dbh tree produced approximately 10 times the volume of branch debris produced by a 50-cm dbh tree. These results highlight the importance of large senescing trees for the production of fallen branch debris and support the keystone role of large trees within remnant woodlands, and the need to conserve these structures. Our results also support the active management of regrowth woodland stands to facilitate the progression of individual trees to maturity and senescence. In particular, thinning of regrowth stands may promote the growth of retained trees, ensuring they contribute to fallen branch debris stocks with a minimum time lag. [ABSTRACT FROM AUTHOR]

The paper seeks to define patterns in the distribution of Australian saltmarsh plants over a continental scale, and test for associations with environmental variables. The distribution of 93 species of Australian saltmarsh plants was documented from the records of the Australian Virtual Herbarium and published reports. The Interim Bioregionalisation of Australia provided a spatial unit for the analysis of patterns of diversity. Saltmarsh diversity was shown to be strongly correlated with latitude and temperature. Multivariate routines including cluster analysis demonstrated consistent geographic patterns in species assemblages. The primary distinction was found to be a north-south divide dissecting the continent at the latitude of 23° south, separating a species-rich southern flora from a species-poor northern flora. Subsequent dissimilarities were defined between coastlines of contrasting orientation. Mean minimum temperature was found to explain nearly 80% of variability in saltmarsh species diversity between bioregions, with diversity inversely related to temperature. [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]

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]

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]

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.

Abstract Although the potential impacts of rising water tables and secondary salinization on agricultural land in southern Australia have been recognized for some time, it is only recently that the impacts on native vegetation have been considered. Despite the likely extent and severity of the problem, no comprehensive approach to assessing the impact of salinity upon native vegetation has been attempted to date. In the present paper, we discuss the causes and impacts of rising water tables and dryland salinity, assess the levels of risk in different ecosystem types and consider the possibilities for the maintenance of biodiversity and ecosystem function in vegetation at risk. We examine the salinity risk to woodland vegetation in the Western Australian (WA) wheatbelt, and consider both broad-scale context and finer-scale variation within individual patches of vegetation. From this information, we develop a set of conceptual models of the potential impacts of shallow saline water tables on ecosystem structure and processes in remnant vegetation in agricultural areas, particularly in the WA wheatbelt. First, we suggest that fine-scale variability in surface topography and soil characteristics may play an important role in limiting the impacts of rising saline water tables. The outcome will depend on the interaction of the heterogeneity of the impact, species distribution in relation to small-scale environmental heterogeneity and variation in species response to hydrological change. Second, we suggest that shallow saline water tables can be considered to cause an ‘edge effect’, which moves inwards from the edge of remnants of native vegetation. Finally, we consider how saline surface flows exacerbate the effects of shallow saline water tables and hasten vegetation decline in remnant areas. We put these models forward as hypotheses to be tested in different situations. We contrast the situation of secondary salinization in Australian vegetation with... [ABSTRACT FROM AUTHOR]