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Addressing threats to biodiversity from pest species is a global challenge. One such challenge is to mitigate the impact of an overabundant Australian songbird, the noisy miner Manorina melanocephala, on woodland birds. The overabundance of noisy miners is listed as a key threatening process under federal biodiversity legislation, but current understanding of where and how noisy miner populations can be managed to yield conservation benefits is unclear. We evaluated the effectiveness of noisy miner removal across 12 treatment areas totaling 3913 ha and nine control areas totaling 1487 ha important for the critically endangered regent honeyeater Anthochaera phrygia. Removal of noisy miners significantly reduced their densities in all but one of the treatment areas. In 10 of the 12 treatment areas, noisy miner densities remained below an impact threshold of 0.65–0.83 birds ha−1 for at least 3 to more than 12 months. The percentage of suitable noisy miner habitat in the surrounding landscape was not a strong predictor of noisy miner management success. Regent honeyeaters occupied six treatment areas, nesting successfully in four. The abundance of other songbirds increased post‐miner removal in seven areas, decreased in three, and was mixed in two. Data from the control areas showed some variation in songbird numbers was independent of noisy miner management. We conclude that noisy miners can be managed in areas of high conservation value for a minimum cost of AUD $10 ha−1. Larger treatment areas may be more important than the broader landscape context in maintaining long‐term noisy miner suppression. Standardized, long‐term monitoring is crucial to identify not only the drivers of pest species recolonization but also locations where threats from pests on endangered species can be addressed effectively while minimizing animal welfare and financial costs. [ABSTRACT FROM AUTHOR]

Monitoring is critical to gauge the effect of environmental management interventions as well as to measure the effects of human disturbances such as climate change. Recognition of the critical need for monitoring means that, at irregular intervals, recommendations are made for new government-instigated programs or to revamp existing ones. Using insights from past well-intentioned (but sadly also often failed) attempts to establish and maintain government-instigated monitoring programs in Australia, we outline eight things that should never be done in environmental monitoring programs (if they aim to be useful). These are the following: (1) Never commence a new environmental management initiative without also committing to a monitoring program. (2) Never start a monitoring program without clear questions. (3) Never implement a monitoring program without first doing a proper experimental design. (4) Never ignore the importance of matching the purpose and objectives of a monitoring program to the design of that program. (5) Never change the way you monitor something without ensuring new methods can be calibrated with the old ones. (6) Never try to monitor everything. (7) Never collect data without planning to curate and report on it. (8) If possible, avoid starting a monitoring program without the necessary resources secured. To balance our "nevers", we provide a checklist of actions that will increase the chances a monitoring program will actually measure the effectiveness of environmental management. Scientists and resource management practitioners need to be part of a stronger narrative for, and key participants in, well-designed, implemented, and maintained government-led monitoring programs. We argue that monitoring programs should be mandated in threatened species conservation programs and all new environmental management initiatives. [ABSTRACT FROM AUTHOR]

Around the world, woodlands have been cleared for agricultural production and their bird communities are in decline. To reverse these declines and foster bird community resilience, government agencies, non‐government organizations, and private landholders have implemented restoration actions, commonly including grazing exclusion and replanting. These actions are rarely implemented in an experimental framework, making it difficult to measure their effectiveness. However, ecological monitoring datasets, and citizen science datasets in particular, can provide useful opportunities for measuring effects of restoration actions and act as a baseline upon which adaptive management can be built. We examined the effect of revegetation actions on the terrestrial bird community in Australia's south‐eastern temperate woodlands using long‐term, community‐collected monitoring datasets. We explored the response of bird abundance, species richness, and a newly developed index of ecological community condition, to grazing exclusion and replanting over a 20‐year period using an uneven control‐impact study design. Grazing exclusion plus replanting had strong positive effects on all three bird community metrics, which increased with time, compared to control sites where neither action occurred. Bird abundance, but not species richness or community condition, increased over time with grazing exclusion alone, while control sites with continued grazing and no replanting showed no change in all three measures. We demonstrate that citizen science datasets with imperfect study designs can be used to gain insights on conservation action effectiveness and highlight the value of metrics that capture information about community condition more precisely than just abundance or species richness. [ABSTRACT FROM AUTHOR]

Biodiversity offsetting is increasingly used to mitigate biodiversity impacts from development, but the practice of offsetting rarely considers how to also mitigate losses of ecosystem services. Offset rules, such as how near an offset must be to an impact site, may help ensure biodiversity offsets also counterbalance losses of ecosystem services but this has not yet well understood.We explored how different rules for siting coastal offsets could change net impacts to a provisioning ecosystem service: fishery resources in Queensland, Australia. A spatially explicit model incorporating supply, flow and demand of fishery resources was developed to simulate contributions of offset sites to commercial fisheries in Queensland, Australia. We simulated offsets for losses due to 63 real projects that damaged mangroves and 14 projects damaging seagrasses.We found that the percentage of species suffering net negative outcomes for the whole commercial fishery increased from about 68% when offsets were located close to impact sites to >85% when there were no restrictions on offset location. All fisheries for seagrass offsets suffered net economic losses under both scenarios, but these were worse when offsets were not required to be near to impact sites.Offsetting outcomes varied substantially across species. Species with shorter maximum dispersal distance and higher dispersal decay parameters suffered greater net losses.Synthesis and applications. Our model quantified impacts of fishery habitat depletion and offsets on fishery resources and the approach can be applied to assess impacts of losses of fishery habitats globally. The findings suggest that to minimize losses of fishery resources caused by habitat depletion, offset policy should generally locate offset sites at the locations available for restoration that are nearest to impact sites, unless specific information about the relative contributions of sites to impacted fisheries is available to guide offset location. [ABSTRACT FROM AUTHOR]

Shorebirds in the East Asian-Australasian Flyway have experienced population declines linked to loss of coastal wetlands. Despite this vulnerability to habitat loss, shorebirds regularly use artificial habitats, especially for high-tide roosting. Understanding the distribution of shorebirds in artificial versus natural roosts could inform habitat management strategies aimed at population recovery. We analysed time-series of high-tide shorebird monitoring data from five developed regions of Australia where artificial habitat use has previously been documented and made three key discoveries. First, artificial habitat use was generally high across the regions, with >50% of the average proportion of the regional population of 39 of 75 species-region combinations (52%) using artificial habitats at high tide. Second, in 84% of species-region combinations the average proportion of birds that used artificial habitats from the time of their establishment onward did not show a significant temporal trend. Third, migratory and coastal specialist species showed lower proportional artificial habitat use than non-migratory and generalist/inland specialist species. These findings showing consistent, widespread use of artificial habitats by large shorebird aggregations at high tide suggest that a framework for high-tide habitat management that includes artificial habitats alongside preservation of remaining natural habitats could make a significant contribution to shorebird conservation in Australia. [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]

Animal vocalisations can signify diverse behavioural contexts, knowledge of which can be applied in bioacoustic monitoring programs. Australia's endemic black cockatoos (Calyptorhynchus sp., family Cacatuidae) are highly vocal species that are threatened in many locations. In this study, we describe the nest‐associated vocal behaviours of two endangered subspecies of black cockatoo, the south‐eastern red‐tailed black cockatoo, C. banksii graptogyne and the Kangaroo Island glossy black cockatoo, C. lathami halmaturinus. Breeding success is limiting their recoveries and nest monitoring is challenging, but vocal recordings might provide valuable long‐term information hard to obtain otherwise. We recorded daily vocal activity at wild nests of both cockatoos using autonomous sound recorders. Combined with behavioural observations and video footage, we identified vocalisations characteristic of six behavioural contexts at nests: birds in flight, while perched, during begging (adult females), during courtship displays (adult males), when entering or sitting near to the nest hollow entrance (adult females), and from nestlings. Linear discriminant analysis on 12 acoustic measurements correctly classified 58.4% of calls of the red‐tailed black cockatoo (n = 907 calls from eight nests) and 62.9% of calls of the glossy black cockatoo (n = 1632 calls from 11 nests). In both subspecies, the female nest call and nestling calls are the most conspicuous vocal indicators of active nesting, and therefore should be considered for their bioacoustic potential. Other adult vocalisations indicate a range of behavioural contexts that could be informative for monitoring nesting behaviour, and its association to habitat features, in these endangered subspecies. [ABSTRACT FROM AUTHOR]

Proponents of development projects (e.g., new roads, mines, dams) are frequently required to assess and manage their impacts on threatened biodiversity. Here, we propose that the environmental legislation and standards that mandate such assessments are failing those threatened species and ecological communities listed as vulnerable. Using a case study of Australia's key environmental legislation, we highlight that vulnerable ecological communities receive no statutory protection, while vulnerable species are held to a less stringent standard in the impact assessment process compared with those that are endangered or critically endangered. In the 19 years since Australia's Environment Protection and Biodiversity Conservation Act 1999 was enacted, four times as many vulnerable species have declined in their threat status than have improved. Beyond Australia, we demonstrate the global relevance of this issue, as it applies to internationally recognized best practice impact assessment guidelines. These cases provide a cautionary tale: without greater attention and stricter assessment criteria in the impact assessment process, the vulnerable species of today risk becoming the endangered species of tomorrow, with all the attendant costs and missed opportunities for recovery that this implies. [ABSTRACT FROM AUTHOR]

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Biodiversity offsetting is widely used to offset negative impacts of development on biodiversity. However, offsets can affect the distribution of benefits among beneficiaries, due to the redistribution of ecosystem services caused by impacts and offsets. Here, we compared the distribution of fishery economic benefits and losses to commercial and recreational fishers under two different offset policy rules: offset locations in close proximity to impact sites, and spatially unrestricted offsetting. With a focus on mangrove and seagrass ecosystems in Queensland, Australia, we measured how the distribution of net outcomes would change using the Gini coefficient. Different offset policy rules had similar effects on the redistribution of fishery benefits among commercial and recreational fishers. However, both offset policy rules failed to fully compensate for losses of fishery benefits for most affected beneficiaries. Locating offsets in close proximity to impact sites achieved slightly more evenly-distributed benefits among recreational fishers and among most types of commercial fishers. The findings suggest that in this system, even though the distribution of net outcomes of impact-offset projects for fishers are somewhat evenly distributed, they tend to be uniformly negative for both recreational and commercial fishers. • Fish habitat offsets in Queensland fails to fully offset losses of fishery benefits for all affected fishery beneficiaries. • Different offset policy rules had similar effects on the redistribution of ecosystem services among beneficiaries. • Offsets generating more even distribution of benefits among beneficiaries may yield smaller ecological gains than losses. [ABSTRACT FROM AUTHOR]

The article focuses on the concept of "nature positive" and its growing adoption as a framework for biodiversity conservation. Topics include Australia's pioneering commitment to nature positive reforms, the challenges in translating these commitments into effective policy, and the proposed steps for achieving genuine nature positive outcomes, such as legislating for absolute net gain and mitigating biodiversity loss from development.

Since European occupation of Australia, human activities have caused the dramatic decline and sometimes extinction of many of the continent's unique species. Here we provide a comprehensive review of threats to species listed as threatened under Australia's Environment Protection and Biodiversity Conservation Act 1999. Following accepted global categories of threat, we find that invasive species affect the largest number of listed species (1257 species, or 82% of all threatened species); ecosystem modifications (e.g. fire) (74% of listed species) and agricultural activity (57%) are also important. The ranking of threats was largely consistent across taxonomic groups and the degree of species' endangerment. These results were significantly different (P < 0.01) from recent analyses of threats to threatened species globally, which highlighted overexploitation, agriculture and urban development as major causes of decline. Australia is distinct not only in the biodiversity it contains but also in the extent and mixture of processes that threaten the survival of these species. Notably, the IUCN threat classification scheme separates the numerous threats (e.g. urban development, agriculture, mining) that cause habitat loss, fragmentation and degradation, hence further research is required to quantify the net impact of these types of habitat change. We provide feasible suggestions for a more coordinated national approach to threatened species conservation, which could provide decision makers and managers at all levels with improved resources and information on threats and management. Adequate policy, legislative support and funding are critical for ensuring that on-ground management is successful in halting the decline of Australia's threatened species. Hundreds of Australian species have experienced significant declines since European occupation and are threatened with extinction. In reviewing the threats affecting these species, we find that invasive species, ecosystem modifications (e.g. fire) and agriculture are most prevalent. We argue that an improved national approach is needed to mitigate these threats. [ABSTRACT FROM AUTHOR]

Highlights • Environmental regulation failed to prevent habitat loss for an endangered species. • Some habitat loss also occurred without government oversight. • Regulatory processes approved over 400 developments without any conditions. Abstract Australia's high species extinction rate shows no sign of abating, with at least three vertebrate extinctions recorded within the last decade. In each case, scientists have published 'post-mortems' examining the context of these recent extinctions. By tracing the decline of a once-widespread and common bird to the point that it has disappeared from over 80% of its original range, and describing the circumstances under which habitat loss continues to be approved despite its formal protection, we present a 'pre-mortem' for the endangered, and endemic, southern black-throated finch (Poephila cincta cincta). The southern black-throated finch has suffered extensive habitat loss historically, much of which was unregulated. In 2000, Australia increased environmental regulation, and the southern black-throated finch was listed under the Commonwealth's Environment Protection & Biodiversity Conservation Act. Despite the increased environmental regulation and formal protection, habitat loss for the southern black-throated finch has continued, mostly incrementally but resulting in large cumulative loss. In the face of steep population decline and range contraction of BTF, five large coal mines were approved between 2012 and 2015 by both State and Commonwealth governments that will remove most of the largest area of high quality habitat that remains. We outline the policy settings under which the decline occurred, with a particular focus on recent ongoing habitat loss occurring within a highly regulated environment. We show that despite Australia's comparatively strong governance and regulatory frameworks, legally permitted habitat loss continues even for imperilled taxa formally listed under State and Commonwealth environment protection laws. [ABSTRACT FROM AUTHOR]

Abstract: Interspecific aggression by the noisy miner (Manorina melanocephala), a highly despotic species, is homogenizing woodland avifaunas across eastern Australia. Although a native species, the noisy miner's aggressive exclusion of small birds is a Key Threatening Process under national law. Large‐scale removal of noisy miners has been proposed as a management response to this threat following increases in miner presence due to anthropogenic land use practices. We tested this proposal by experimentally removing noisy miners from eucalypt woodland remnants (16–49 ha), assigned randomly as control (n = 12) or treatment (miner removal) sites (n = 12). Standardized bird surveys were conducted before and after removal, and generalized linear mixed models were used to investigate the effect of miner removal on bird assemblage metrics. Despite removing 3552 noisy miners in three sessions of systematic shooting, densities of noisy miners remained similarly high in treatment and control sites, even just 14 days after their removal. However, there was evidence of an increase in richness and abundance of small birds in treatment sites compared to controls—an effect we only expected to see if noisy miner densities were drastically reduced. We suggest that miner removal may have reduced the ability of the recolonizing miners to aggressively exclude small birds, even without substantially reducing miner densities, due to the breakdown of social structures that are central to the species' despotic behaviour. However, this effect on small birds is unlikely to persist in the long term. Synthesis and applications: Despite evidence from other studies that direct removal of noisy miners can result in rapid and sustained conservation benefit for bird communities at small scales, our findings cast doubt on the potential to scale‐up this management approach. The circumstances under which direct control of noisy miners can be achieved remain unresolved. [ABSTRACT FROM AUTHOR]

Biodiversity offset trades usually aim to achieve ‘no net loss’ of biodiversity. But the question remains: no net loss compared to what? Determining whether an offset can compensate for a given impact requires assumptions about the counterfactual scenario—that which would have happened without the offset—against which the gain at an offset site can be estimated. Where this counterfactual scenario, or ‘crediting baseline’, assumes a future trajectory of biodiversity decline, the intended net outcome of the offset trade is maintenance of that declining trajectory. If the rate of decline of the crediting baseline is implausibly steep, biodiversity offset trades can exacerbate biodiversity decline. We examined crediting baselines used in offset policies across Australia, and compared them with recent estimates of decline in woody vegetation extent. All jurisdictions permitted offset credit generated using averted loss—implying an assumption of background decline—but few were explicit about their crediting baseline. The credit calculation approaches implied assumed crediting baselines of up to 4.2% loss (of vegetation extent and/or condition) per annum; on average, the crediting baselines were >5 times steeper than recent rates of vegetation loss. For these crediting baselines to be plausible, declines in vegetation condition must be rapid, but this was not reflected in the approaches for which assumptions about decline in extent and condition could be separated. We conclude that crediting baselines in Australian offset schemes risk exacerbating biodiversity loss. The near-ubiquitous use of declining crediting baselines risks ‘locking in’ biodiversity decline across impact and offset sites, with implications for biodiversity conservation more broadly. [ABSTRACT FROM AUTHOR]

Fire plays an important role in maintaining grassy forests, and reduced fire frequency has been linked to encroachment of woody plants into grassy forests and woodlands globally. In Australia a range of threatened animals, including the northern population of the endangered eastern bristlebird (Dasyornis brachypterus), are dependent on grassy forests. We examined this issue by collating three decades of detailed monitoring and fire data for 43 current and historically-occupied bristlebird sites, and examined the relationships among fire history, bristlebird occupancy and habitat patch size/condition. Habitat patch size declined by over 50% between 1980 and 2009 due to woody plant encroachment. Bristlebird occupancy was associated with reduced habitat loss and time since fire, while reduced fire frequency was the main predictor of decline in grassy cover, a critical habitat element for bristlebirds. Our models suggested habitat loss was strongly influenced by fire history, particularly fire frequency, with reduced habitat loss associated with more-frequent burning. Native grass cover can return quickly, and remained high until 5–10 years post-fire; densest grass cover was found at sites with fire intervals of between 3.5 and 7 years. Active fire management, including regular ecological burning, is imperative for conservation of the eastern bristlebird and other threatened fauna that depend on these grassy forests. The massive changes in global patterns of fire currently occurring, and the threat this poses to biodiversity, make understanding the nuances of fire ecology, including the role of fire frequency, essential to improving conservation management. [Display omitted] [ABSTRACT FROM AUTHOR]

Accounting for differences in abundances among species remains a high priority for community ecology. While there has been more than 80 years of work on trying to explain the characteristic S shape of rank-abundance distributions (RADs), there has been recent conjecture that the form may not depend on ecological processes per se but may be a general phenomenon arising in many unrelated disciplines. We show that the RAD shape can be influenced by an ecological process, namely, interference competition. The noisy miner ( Manorina melanocephala) is a hyperaggressive, 'despotic' bird that occurs over much of eastern Australia (>10km). We compiled data for bird communities from 350 locations within its range, which were collected using standard avian survey methods. We used hierarchical Bayesian models to show that the RAD shape was much altered when the abundance of the strong interactor exceeded a threshold density; RADs consistently were steeper when the density of the noisy miner ≥2.5 birds ha. The structure of bird communities at sites where the noisy miner exceeded this density was very different from that at sites where the densities fell below the threshold: species richness and Shannon diversity were much reduced, but mean abundances and mean avian biomass per site did not differ substantially. [ABSTRACT FROM AUTHOR]

Globally, modification of landscapes for agriculture has had a strong influence on the distribution and abundance of biota. In particular, woodland-dependent birds are under threat across agricultural landscapes in Britain, North America and Australia, with their decline and extirpation attributed to the loss and fragmentation of habitat. Other native species have become over-abundant in response to anthropogenic landscape change and have strong interactive effects on avian assemblage structure. In eastern Australia, the hyper-aggressive noisy miner ( Manorina melanocephala) often dominates woodlands in agricultural landscapes through interspecific competition, resulting in declines of species richness of woodland-dependent birds. We aimed to determine the relative influence and importance of interspecific competition, in situ habitat structure and landscape structure for woodland-dependent bird species at the landscape level. We recorded species-specific landscape incidence of woodland-dependent birds in 24 agricultural-woodland mosaics (25 km 2) in southern Queensland, Australia. We selected extensively cleared landscapes (10–23 % woodland cover) where fragmentation effects are expected to be greatest. We applied generalised linear models and hierarchical partitioning to quantify the relative importance of the landscape-level incidence of the noisy miner, mistletoe abundance, shrub cover, woodland extent, woodland subdivision and land-use intensity for the incidence of 46 species of woodland birds at the landscape-scale. The landscape-level incidence of the noisy miner was the most important explanatory variable across the assemblage. Both in situ habitat structure and landscape structure were of secondary importance to interspecific aggression, although previous research suggests that the increasing incidence of the noisy miner in fragmented agricultural landscapes is itself a consequence of anthropogenic changes to landscape structure. Species’ responses to fragmentation varied from positive to negative, but complex habitat structure had a consistently positive effect, suggesting in situ restoration of degraded habitats could be a conservation priority. Landscape wide conservation of woodland-dependent bird populations in agricultural landscapes may be more effective if direct management of noisy miner populations is employed, given the strong negative influence of this species on the incidence of woodland-dependent birds among landscapes. [ABSTRACT FROM AUTHOR]

In this study, we aimed to explore the effect of fires on bird diversity in Australia's tropical savannas. Bird surveys were conducted at 69 sites between 2005 and 2007 to estimate bird species richness and abundance within the Mornington Sanctuary, the Kimberley, north-west Australia. We used MODIS (Moderate Resolution Imaging Spectroradiometer) and Landsat satellite imagery to map fire scars and to quantify vegetation cover parameters, and QuickBird imagery to map the percentage tree cover. Bird species richness and abundance were higher in areas exhibiting minimum seasonal and interannual changes, e.g. in riparian areas, near water and where tree cover was high. We found a significant negative effect of fire on bird diversity following the extensive late dry-season fires of 2006. These findings support the view that intense and large fires are threatening biodiversity and reinforce the importance of reducing the occurrence of late dry-season fires, which are the most severe and extensive. MODIS satellite imagery was found to provide a cost-effective approach to monitoring savanna landscapes, assessing the state of vegetation and monitoring fire dynamics. We used remote sensing for mapping fire dynamics in the tropical savannas of Australia and to study the effects of fire on bird diversity. Our results suggest that large late dry-season fires have a negative effect on bird diversity and that MODIS imagery at a spatial resolution of 250 m is cost-effective for monitoring vegetation and fires in these areas. [ABSTRACT FROM AUTHOR]

The identification of environmental factors linked to increased risk of local extinction often relies on inference from patterns of distribution. Yet for declining populations, the assumption of population equilibrium that underlies species distribution models is violated. Measures such as individual condition can provide a more direct indication of extinction risk, and can start to be detected before declines commence. We compared distribution-based and condition-based approaches to identifying factors affecting habitat suitability for an area-sensitive passerine, the eastern yellow robin Eopsaltria australis, in eastern Australia. We compared patterns of individual condition between robins and several common, more mobile species (Meliphagid honeyeaters and yellow thornbills Acanthiza nana). Robin presence was not affected by landscape context, but robins avoided sites with a more grassy ground layer. However, robins inhabiting landscapes with less remnant woodland had higher ratios of heterophils to lymphocytes in peripheral blood, indicating higher long-term stress. No clear spatial patterns of condition were detected for the more mobile species. Our findings suggest a hierarchical model of habitat suitability, whereby robins avoid grassy sites, but where they do occur are in poorest condition when inhabiting less-vegetated landscapes. We predict greater rates of local extinction of robins from such landscapes. The use of indicators of individual condition, in addition to distribution data, can unveil otherwise cryptic factors as important influences on habitat quality. As habitat occupancy does not always reflect habitat quality, exploring patterns in condition indices can complement species distribution modelling, potentially revealing threats to persistence before population declines have commenced. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Thresholds often exist in the relationship between species richness and the area of remaining habitat in human-modified landscapes, prompting debate about the mechanisms responsible. We hypothesize that if species-area relationships differ with underlying factors such as landscape productivity, and such factors correlate with patterns of habitat clearance, then spurious thresholds can arise where the separate species-area relationships intersect. We assessed whether this phenomenon could explain landscape-level species-area relationships for birds occupying 31 landscapes of 100 km2 in eastern Australia. Location Eastern Australia. Methods Landscape-level species richness estimates were modelled as a function of the percentage of native vegetation remaining in the study landscapes. The performance of traditional species-area curves and continuous and discontinuous piecewise models was compared using an information theoretic approach. Separate models for high- and low-productivity and high- and low-fragmentation landscapes were examined to determine whether they implied different species-area relationships. Results The species-area relationship exhibited a rapid change-point at approximately 40% vegetation cover, but this was most parsimoniously explained by two disjunct slopes rather than a continuous threshold model or a classic species-area curve. Exploration of models fitted separately to high- and low-productivity landscapes suggested that such landscapes may differ in their characteristic species-area relationships. Main conclusions The observed pattern is consistent with the spurious threshold hypothesis, and opens a new avenue of enquiry into the processes behind apparent ecological thresholds. This hypothesis may be valid in other regions where clearing history is confounded by underlying factors such as landscape productivity, and demands further research. In such systems, real thresholds for different landscape types may occur at different levels of cover, or might not exist at all. If so, a simple space-for-time substitution may not be valid, and management prescriptions based on threshold values (e.g. 40%) will be flawed. [ABSTRACT FROM AUTHOR]

Some species have disproportionate influence on assemblage structure, given their numbers or biomass. Most examples of such "strong interactors" come from small-scale experiments or from observations of the effects of invasive species. There is evidence that entire avian assemblages in open woodlands can be influenced strongly by individual species over very large areas in eastern Australia, with small-bodied species (<50 g) being adversely affected. We used data from repeated surveys in 371 sites in seven districts across a region from Victoria to Queensland (>2000 km). A series of linked Bayesian models was used to identify large-bodied (=50 g) bird species that were associated with changes in occurrence and abundance of small-bodied species. One native species, the Noisy Miner (Manorina melanocephala; family Meliphagidae), was objectively identified as the sole large-bodied species having similar detrimental effects in all districts, depressing occurrence of 57 of 71 small-bodied species. Adverse effects on abundances of small-bodied species were profound when the Noisy Miner occurred with mean site abundances = 1.6 birds/2 ha. The Noisy Miner may be the first species to have been shown to influence whole-of-avifauna assemblage structure through despotic aggressiveness over subcontinental scales. These substantial shifts in occurrence rates and abundances of small-bodied species flow on to alter species abundance distributions of entire assemblages over much of eastern Australia. [ABSTRACT FROM AUTHOR]

Adaptive management is an iterative process of gathering new knowledge regarding a system's behavior and monitoring the ecological consequences of management actions to improve management decisions. Although the concept originated in the 1970s, it is rarely actively incorporated into ecological restoration. Bayesian networks (BNs) are emerging as efficient ecological decision-support tools well suited to adaptive management, but examples of their application in this capacity are few. We developed a BN within an adaptive-management framework that focuses on managing the effects of feral grazing and prescribed burning regimes on avian diversity within woodlands of subtropical eastern Australia. We constructed the BN with baseline data to predict bird abundance as a function of habitat structure, grazing pressure, and prescribed burning. Results of sensitivity analyses suggested that grazing pressure increased the abundance of aggressive honeyeaters, which in turn had a strong negative effect on small passerines. Management interventions to reduce pressure of feral grazing and prescribed burning were then conducted, after which we collected a second set of field data to test the response of small passerines to these measures. We used these data, which incorporated ecological changes that may have resulted from the management interventions, to validate and update the BN. The network predictions of small passerine abundance under the new habitat and management conditions were very accurate. The updated BN concluded the first iteration of adaptive management and will be used in planning the next round of management interventions. The unique belief-updating feature of BNs provides land managers with the flexibility to predict outcomes and evaluate the effectiveness of management interventions. [ABSTRACT FROM AUTHOR]

General guidelines available to revegetation planners focus on the spatial context and dimensions of the revegetated site. However, site-specific habitat factors can have overarching importance for habitat value, especially where interactions with competitors or predators may play an important role. Current revegetation projects in Australia which aim to restore slow-growing buloke (Allocasuarina luehmannii) woodland, a threatened habitat important for bird conservation, usually include faster-growing eucalypts in plantings. This research aimed to identify whether eucalypt presence in buloke woodland facilitates invasion by the noisy miner (Manorina melanocephala), an aggressive competitor that is absent from pure buloke woodland. Birds were surveyed in buloke woodland remnants that contained eucalypts as a sub-dominant species at densities of 0–16 per ha. The probability of noisy miner presence in buloke woodland increased markedly where eucalypts were present at a density of approximately five per hectare. The presence of noisy miners resulted in a substantial difference in bird assemblage structure and composition. Small-bodied insectivorous birds which are experiencing population declines in southern Australia were recorded on average six times more often in transects without noisy miners (low-eucalypt density transects). Avian behaviour and habitat use was also altered, with birds flying more frequently in transects where noisy miners were present. A minor difference in habitat composition results in substantial degradation of the conservation value of non-eucalypt woodland in eastern Australia due to invasion by aggressive avian competitors. Revegetation and restoration practices should take into account the potential for such subtle floristic differences to result in substantial variation in conservation outcomes. [Copyright &y& Elsevier]

The global trend toward more intensive forms of agriculture is changing the nature of matrix habitat in agricultural areas. Removal of components of matrix habitat can affect native biota at the paddock and the landscape scale, particularly where intensification occurs over large areas. We identify the loss of paddock trees due to the proliferation of centre pivot irrigation in dryland farming areas as a potentially serious threat to the remnant biota of these areas. We used a region of south-eastern Australia as a case study to quantify land use change from grazing and dryland cropping to centre pivot irrigation over a 23-year period. We also estimated rates of paddock tree loss in 5 representative landscapes within the region over the same period. The total area affected by centre pivots increased from 0ha in 1980 to nearly 9000ha by 2005. Pivots were more likely to be established in areas which had originally been plains savannah and woodlands containing buloke (Allocasuarina luehmannii), a food source for an endangered bird. On average, 42% of paddock buloke trees present in 1982 were lost by 2005. In the two landscapes containing several centre pivots, the loss was 54% and 70%. This accelerated loss of important components of matrix habitat is likely to result in species declines and local extinctions. We recommend that measures to alleviate the likely negative impacts of matrix habitat loss on native biota be considered as part of regional planning strategies. [Copyright &y& Elsevier]

Bird assemblages generally are no longer regarded as stable entities, but rather as fluctuating in response to many factors. Australia's highly variable climate is likely to result in a high degree of dynamism in its bird assemblages, yet few studies have investigated variation on an inter-annual temporal scale. We compared 2 year-long samples of the bird assemblages of a series of highly fragmented buloke Allocasuarina luehmannii (Casuarinaceae) woodland remnants in south-eastern Australia, the first sample taken in 1994–95 and the second in 2001–02. Bird densities were almost three times higher in the second period than in the first. Mean species richness also was significantly higher. Species richness of each individual site was unrelated between the 2 years. Minimum species turnover was 63% and was higher, on average, for migratory and nomadic than for sedentary species. Therefore, site-level bird assemblage composition was markedly different between the two survey periods and, on average, the assemblage composition of each site bore greater resemblance to those of other sites in the same year than to that of the same site in the other survey period. Most species changed substantially in their distribution among remnants between the two periods. The change in distribution of most species did not differ significantly from that expected if the species had redistributed at random among the sites. This suggests that although the remnant vegetation of the area is highly fragmented with minimal interpatch connectivity, bird movements among remnants are relatively frequent. Inter-annual variability in Australian bird assemblages may be higher than is commonly recognized. In such dynamic systems, we must be cautious when extrapolating from the findings of short-term studies to longer temporal scales, especially in relation to conservation management. A greater understanding of the processes driving distributional patterns is likely to enable better predictions of species’ responses to habitat change. [ABSTRACT FROM AUTHOR]

Many nations are struggling to reduce deforestation, despite having extensive environmental protection laws in place and commitments to international agreements that address the biodiversity and climate crises. We developed a novel framework to quantify the extent to which contemporary deforestation is being captured under national and subnational laws. We then applied this framework to northern Australia as a case study, a development and deforestation hotspot with ecosystems of global significance. First, deforestation may be compliant under all relevant legislation, either through assessment and approval or because of exemptions in the legislation. Second, deforestation may be compliant under at least one relevant law, but not all. Third, there may be no evidence of deforestation assessment or exemption from assessment, despite their apparent requirement, which could mean the deforestation is potentially noncompliant. Finally, deforestation may occur in an area or under circumstances that are beyond the intended scope of any relevant legislation. All deforestation that we analyzed was hypothetically covered by one or more laws. However, 65% of deforestation was potentially noncompliant with at least one law. Because multiple laws could be relevant to a given clearing event, the majority of clearing was still compliant with at least one law, but of these events, only a small proportion was explicitly approved (19%). The remaining were permitted under various exemptions. Of all the legislation we analyzed, most of the exempt clearing occurred under one subnational law and most potentially noncompliant clearing occurred under one national law. Our results showed that even a nation with a suite of mature environmental protection laws is falling well short of achieving international commitments regarding deforestation. Our framework can be used to pinpoint the pathways of policy change required for nations to align local laws with these international accords. [ABSTRACT FROM AUTHOR]

As with most governments worldwide, Australian governments list threatened species and proffer commitments to recovering them. Yet most of Australia's imperiled species continue to decline or go extinct and a contributing cause is inadequate investment in conservation management. However, this has been difficult to evaluate because the extent of funding committed to such recovery in Australia, like in many nations, is opaque. Here, by collating disparate published budget figures of Australian governments, we show that annual spending on targeted threatened species recovery is around U.S.$92m (AU$122m) which is around one tenth of that spent by the U.S. endangered species recovery program, and about 15% of what is needed to avoid extinctions and recover threatened species. Our approach to estimating funding needs for species recovery could be applied in any jurisdiction and could be scaled up to calculate what is needed to achieve international goals for ending the species extinction crisis. [ABSTRACT FROM AUTHOR]

Since European occupation of Australia, human activities have caused the dramatic decline and sometimes extinction of many of the continent's unique species. Here we provide a comprehensive review of threats to species listed as threatened under Australia's Environment Protection and Biodiversity Conservation Act 1999. Following accepted global categories of threat, we find that invasive species affect the largest number of listed species (1257 species, or 82% of all threatened species); ecosystem modifications (e.g. fire) (74% of listed species) and agricultural activity (57%) are also important. The ranking of threats was largely consistent across taxonomic groups and the degree of species' endangerment. These results were significantly different (P 0.01) from recent analyses of threats to threatened species globally, which highlighted overexploitation, agriculture and urban development as major causes of decline. Australia is distinct not only in the biodiversity it contains but also in the extent and mixture of processes that threaten the survival of these species. Notably, the IUCN threat classification scheme separates the numerous threats (e.g. urban development, agriculture, mining) that cause habitat loss, fragmentation and degradation, hence further research is required to quantify the net impact of these types of habitat change. We provide feasible suggestions for a more coordinated national approach to threatened species conservation, which could provide decision makers and managers at all levels with improved resources and information on threats and management. Adequate policy, legislative support and funding are critical for ensuring that on-ground management is successful in halting the decline of Australia's threatened species. [ABSTRACT FROM AUTHOR]

Offsetting impacts on fishery resources under losses of marine habitats due to development is important to help safeguard seafood security. However, the gains that marine habitat restoration can create for fishery resources remain largely unquantified. It is unknown what area of fish habitats must be restored to fully offset a hectare of development impacts. Here, we quantify minimum offset areas required to achieve different indicators of no net loss (NNL) goals: economic value, catch of each species, and catch of most-caught species. Simulations are conducted by using a case study of mangrove habitat offsets in Australia to infer the minimum restoration area needed to fully offset fishery losses caused by 84 development projects. We establish two offset policy rules: offsetting closest to the impact site, and offsetting to maximise benefit regardless of location. Achieving NNL for all fishery species requires a substantially larger offset multiplier than achieving NNL for most-caught species, or for economic benefits. For all NNL objectives, choosing optimal offset sites can minimise the area needed for restoration, but required multipliers still always >1. The amount of offset area required to achieve NNL goals for fisheries per unit area lost for each development project increases as development projects accumulated, since the suitable sites for offsetting become scarcer. These results reveal the large and increasing costs of fully offsetting marine impacts and the increasing risks, especially where suitable offset sites are likely to be scarce. • Different offset policy rules require varying minimum offset areas for no net loss of ecosystem services. • Area of fish habitat restoration needed for no net loss of fishery benefits tend to increase as impacts accumulate. • Offsetting losses of fishery ecological benefits needs more habitats than that for fishery economic benefits. [ABSTRACT FROM AUTHOR]

Abstract: Temperate Australia’s wheat/sheep zone and much of Western Europe have both experienced dramatic declines in native bird populations associated with agricultural landscapes. We compare recent conservation strategies on private land in the context of each region’s historical agricultural development and the ecology of its bird fauna. Specifically, we consider which aspects of the conservation instruments and practices employed in European agricultural landscapes might be used to augment and inform approaches to private-land biodiversity conservation in Australia. Australian biodiversity conservation activities have focussed predominantly on remnant native vegetation and rarely target the agricultural matrix (i.e. land that is primarily used for agricultural production). However, declining species include those that not only primarily inhabit woodland, but also species for which components of the agricultural matrix are important, or even their main, habitat. In contrast, in Europe a range of conservation activities undertaken through agri-environment schemes focus explicitly on the management of the agricultural matrix. Whilst the different approaches to conservation on private land in Australia and Europe reflect the two continents’ different ecologies, land-use histories and political economies of agriculture, there are a number of parallels between bird population declines in the two regions, and an opportunity may exist to incorporate some of the successful aspects of the European agri-environment approach into emerging stewardship schemes in Australia. We suggest that the long-term nature of European agri-environment agreements, the principle of landholder payments more commensurate with reduced production opportunity and management actions specifically targeted at the agricultural matrix, are features of the European scheme that could benefit both woodland- and matrix-inhabiting bird species in Australian agricultural landscapes. [Copyright &y& Elsevier]

Deforestation threatens the earth's biodiversity and the ecosystem services upon which humans depend. Formal regulation is a key mechanism by which governments seek to protect forests. However, whether regulation can effectively protect remaining areas of the most threatened and most heavily cleared forests is unknown. We addressed this question using forest loss data for Queensland, Australia between 2000 and 2014 under existing vegetation clearing regulation ( Vegetation Management Act 1999 ). This regulation is specifically designed to provide the greatest protection for threatened forest types that have already lost the greatest amount of their original extent. Importantly, enforcement and governance of this regulation is relatively strong allowing an assessment of regulation design. We applied path analysis to model the direct and indirect effects (mediated by variables representing deforestation pressure) of forest protection level on clearing rates. There was strong evidence for a decline in clearing rates over time, except of clearing for non-agricultural purposes. However, threatened forest types, which have already lost > 70% of their original extent and should have the greatest level of protection under the regulation, continue to be cleared 2.7–2.9 times faster than non-threatened forest types. There was also little evidence that the regulation has driven greater reductions over time in the clearing rates of threatened versus non-threatened forests types. There was much greater support for the indirect than direct effect of protection level. This is because protection level was correlated with variables associated with deforestation pressure, resulting in higher clearing rates for threatened compared to non-threatened forest types. We hypothesise that this arises because the additional protection afforded to threatened relative to non-threatened forests is insufficient to counter the continuing higher level of deforestation pressure on threatened forests. We argue that a potential solution is to build explicit targets for forest retention into regulation, below which no further forest loss is permitted. This could be combined with spatially targeted enforcement and incentive strategies where threats are highest. [ABSTRACT FROM AUTHOR]

Earth's extinction crisis is escalating, and threat classification schemes are increasingly important for assessing the prominent drivers and threats causing species declines. However, a complementary framework for assessing the conservation responses needed to abate these threatening processes is lacking. Here we draw on expert knowledge and published literature to develop a threat-abatement framework which groups threats based on the shared conservation goal of the actions needed to abate their impact and apply it to 1532 threatened species across the Australian continent. Our analysis shows that the most important conservation actions across Australia are to retain and restore habitat, due to the threats posed by habitat destruction and degradation (via logging, mining, urbanisation, roads, and agriculture) to 86 % of Australia's threatened species. Most species also require the effective control of invasive species and diseases (82 %) and improved fire management (66 %). Countering individual threats will not be enough to support species survival or recovery, because almost all species (89 %) require multiple, integrated management responses to redress their threats. Our threat abatement framework enables rapid identification of broad conservation responses to aid recovery of threatened species and can be applied in other regions, scales and contexts. • Threat classifications need complementary conservation responses to inform action • We develop a threat-abatement framework and apply it to Australian threatened species • The most important conservation action in Australia is to retain and restore habitat • Control of invasive species/diseases and improved fire management are also important • Greater emphasis on conservation responses is needed to redress the extinction crisis [ABSTRACT FROM AUTHOR]

Australia's 2019-2020 mega-fires were exacerbated by drought, anthropogenic climate change and existing land-use management. Here, using a combination of remotely sensed data and species distribution models, we found these fires burnt ~97,000 km 2 of vegetation across southern and eastern Australia, which is considered habitat for 832 species of native vertebrate fauna. Seventy taxa had a substantial proportion (>30%) of habitat impacted; 21 of these were already listed as threatened with extinction. To avoid further species declines, Australia must urgently reassess the extinction vulnerability of fire-impacted species and assist the recovery of populations in both burnt and unburnt areas. Population recovery requires multipronged strategies aimed at ameliorating current and fire-induced threats, including proactively protecting unburnt habitats.

The term critical habitat is used to describe the subset of habitat that is essential to the survival and recovery of species. Some countries legally require that critical habitat of listed threatened and endangered species be identified and protected. However, there is little evidence to suggest that the identification of critical habitat has had much impact on species recovery. We hypothesized that this may be due at least partly to a mismatch between the intent of critical habitat identification, which is to protect sufficient habitat for species persistence and recovery, and its practice. We used content analysis to systematically review critical habitat documents from the United States, Canada, and Australia. In particular, we identified the major trends in type of information used to identify critical habitat and in occupancy of habitat identified as critical. Information about population viability was used to identify critical habitat for only 1% of the species reviewed, and for most species, designated critical habitat did not include unoccupied habitat. Without reference to population viability, it is difficult to determine how much of a species' occupied and unoccupied habitat will be required for persistence. We therefore conclude that the identification of critical habitat remains inconsistent with the goal of protecting sufficient habitat to support persistence and recovery of the species. Ensuring that critical habitat identification aligns more closely with its intent will improve the accuracy of the designations and may therefore help improve the benefits to species recovery when combined with adequate implementation and enforcement of legal protections., (© 2014 Society for Conservation Biology.)

Some species have disproportionate influence on assemblage structure, given their numbers or biomass. Most examples of such "strong interactors" come from small-scale experiments or from observations of the effects of invasive species. There is evidence that entire avian assemblages in open woodlands can be influenced strongly by individual species over very large areas in eastern Australia, with small-bodied species (< 50 g) being adversely affected. We used data from repeated surveys in 371 sites in seven districts across a region from Victoria to Queensland (> 2000 km). A series of linked Bayesian models was used to identify large-bodied (> or = 50 g) bird species that were associated with changes in occurrence and abundance of small-bodied species. One native species, the Noisy Miner (Manorina melanocephala; family Meliphagidae), was objectively identified as the sole large-bodied species having similar detrimental effects in all districts, depressing occurrence of 57 of 71 small-bodied species. Adverse effects on abundances of small-bodied species were profound when the Noisy Miner occurred with mean site abundances > or = 1.6 birds/2 ha. The Noisy Miner may be the first species to have been shown to influence whole-of-avifauna assemblage structure through despotic aggressiveness over subcontinental scales. These substantial shifts in occurrence rates and abundances of small-bodied species flow on to alter species abundance distributions of entire assemblages over much of eastern Australia.