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Abstract Biodiversity offsets are a popular policy tool for mitigating the impact of development on biodiversity, but the ecological success of offsets arise from complex interactions among socio‐economic, ecological and policy processes, making outcomes challenging to assess. Many offset policies use habitat surrogates to determine offset requirements, rather than using direct measures of impacted biota, and this can lead to poor outcomes for species. One potential solution to this is for offsets to be delivered by a public agency (agency‐led) rather than by developers (developer‐led). This is because agencies may be able to strategically choose offset sites that maximise outcomes for species (e.g. abundance), while there may be little reason for developers to act strategically in this way when offset requirements are based purely on habitat surrogates. Yet, the success of a strategic agency‐led approach is likely to depend on patterns of development and offset site availability. To examine this, we developed a novel integrated spatially explicit model of land‐use change, habitat, species abundance and offset regulation. We apply the model to the Queensland Government's Environmental Offsets Policy for koalas Phascolarctos cinereus in South East Queensland, Australia, and test how patterns of development and offset site availability influence the performance of agency‐led versus developer‐led offsets. When potential offset sites were plentiful, agency‐led offsets tended to outperform developer‐led offset delivery for maximising koala abundance while achieving similar or better outcomes for habitat area. Yet, when potential offset sites were rare, the relative performance of agency‐led offset was often poor, and offset requirements for habitat area were less likely to be met. Different spatial patterns of development had little effect on the relative performance of agency‐led versus developer‐led offsets. Our analysis shows that agency‐led offsets with strategic choices of offset sites can improve species' outcomes for habitat‐based offsets but can also risk failing to meet habitat area requirements when the availability of offset sites is low. Importantly, our integrated spatial model provides a holistic approach to assessing policy options for biodiversity offsets in dynamic human‐modified landscapes. Read the free Plain Language Summary for this article on the Journal blog.

Although several countries along the East Asian-Australasian Flyway have recently begun reporting population trends and identifying threats to migratory waterbirds, there remains rather sparse geographical coverage of systematic waterbird monitoring, impeding our understanding of the flyway-wide status of waterbird populations. To fill this gap, we used the data from a nationwide citizen science project, the “Taiwan New Year Bird Count'' to examine recent population trends of 31 migratory waterbird species across Taiwan, and within three of its waterbird hotspot regions, between 2014 and 2021. Island-wide, the abundance of two species declined significantly while five species increased. However, there was substantial heterogeneity in population trends among regions, with nine species declining significantly in Yi-Lan, four species in Chang-Hua and one species in Chia-Nan. Conversely, 11 species increased significantly in Chia-Nan, one species in Chang-Hua, but no species increased in Yi-Lan. This suggests that a combination of local and remote factors is driving population change in Taiwanese migratory waterbirds. Moreover, species that use local rice paddies or are dependent on tidal flats around the Yellow Sea were more likely to show population declines, and those able to use aquacultural wetlands showed growth. These results suggest that recent rice paddy loss and habitat loss in the Yellow Sea have been contributing to migratory waterbird declines in Taiwanese wetlands. Our findings suggest that local land use planning policies within Taiwan as well as mitigation of Yellow Sea tidal flat loss are likely to be complementary in safeguarding the future of migratory waterbirds in Taiwan.

Abstract 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.

Multi-species indicators (MSIs) have been useful tools for reflecting the state of taxa and ecosystems at global, regional, and national levels. However, most indicators are from Europe and North America, and there are few from the world’s major tropical and subtropical biodiversity hotspots, often in large part because of insufficient data availability. We modelled the population trajectories of 107 regularly-occurring breeding bird species in Taiwan (100 native and seven introduced species) and developed MSIs for (i) forest, (ii) farmland, and (iii) introduced bird species based on the Taiwan Breeding Bird Survey dataset between 2011 and 2019. Individual population trajectories for 87 species did not show a significant change, those for 11 species grew significantly, and those for two species declined significantly. All MSIs show significant growth. Based on the phylogenetic generalised least squares (PGLS) results, the forest bird indicator increased somewhat more rapidly than the farmland bird indicator, perhaps reflecting very low rates of deforestation contrasting with more rapid land use change on farmlands in Taiwan. Some of the forest and farmland species, however, showed rapid declines, and most of these atypical decliners were common species or carnivores. Further, the PLGS results show that the introduced species indicator had more rapid growth than native species indicators, posing a potential risk for the integrity of native bird communities in the near future as well as compromising broader ecosystem intactness. Our study provides important information on bird population changes in subtropical Asia. The MSIs will be updated regularly and will be used to provide information to support conservation policies in Taiwan.

Abstract The fulfilment of the benefits resulting from services provided by nature requires an integrated framework that combines appropriate ecosystem service governance with spatially explicit models of service provision. Here, we propose using a social‐ecological network approach to develop a ‘landscape governance framework’ that identifies how different types of governance can act on supply, demand and flow of ecosystem services through changes in landscape structure and connections. Starting from undesirable situations where demand exceeds supply, we exemplify the application of this conceptual model considering hierarchical (e.g. creation of protected areas), market (e.g. payments for environmental services) and community‐based (e.g. enhancing links between stakeholders) governance approaches. We show how interventions associated with each of these approaches act in distinct ways to regulate different components of the service provision chain in heterogeneous landscapes. Filling such knowledge gaps can help identify appropriate governance interventions depending on factors that limit provision: restricted supply, demand or flow. The application of the landscape governance framework entails challenges related to availability of data and limited understanding of key underlying mechanisms. However, it opens important new research questions at the interface between governance and ecosystem services, with great potential as a tool for landscape management that aims to achieve ecosystem service sustainability. A free Plain Language Summary can be found within the Supporting Information of this article.

Abstract Increasingly, government and corporate policies on ecological compensation (e.g., offsetting) are requiring “net gain” outcomes for biodiversity. This presents an opportunity to align development with the United Nations Convention on Biological Diversity Post‐2020 Global Biodiversity Framework's (GBF) proposed ambition for overall biodiversity recovery. In this perspective, we describe three conditions that should be accounted for in net gain policy to align outcomes with biodiversity recovery goals: namely, a requirement for residual losses from development to be compensated for by (1) absolute gains, which are (2) scaled to the achievement of explicit biodiversity targets, where (3) gains are demonstrably feasible. We show that few current policies meet these conditions, which risks undermining efforts to achieve the proposed Post‐2020 GBF milestones and goals, as well as other jurisdictional policy imperatives to halt and reverse biodiversity decline. To guide future decision‐making, we provide a supporting decision tree outlining net gain compensation feasibility.

Countries are adopting ecological compensation policies aimed at achieving no net loss of biodiversity and ecosystem services. Here, Sonter and colleagues apply spatial simulation models to case studies in Australia, Brazil, Indonesia, and Mozambique to show that compensation alone is not sufficient to preserve biodiversity.

Abstract Controlling problem species for conservation can be fraught, particularly when native species are subject to lethal control. The noisy miner (Manorina melanocephala), has been the target of numerous lethal control efforts. Outcomes of these noisy miner removals have varied substantially, so identifying the circumstances under which they are effective is essential for ethical and effective management. We compiled data for all identified noisy miner removals (n = 45), including both permit‐based and unofficial removals. We investigated whether methodological and ecological factors explained the effectiveness of removals in reducing noisy miner density or increasing woodland bird richness and abundance. The only predictor of any measure of success was time between first and final culls which was positively related to reduction in noisy miner density. Surprisingly, despite removals mainly failing to reduce noisy miner density to below a threshold above which noisy miners impact smaller birds, woodland birds usually still increased. Disrupted social structure as noisy miners recolonized may have led to less effective aggressive exclusion of small birds. Further removals may not need to reduce noisy miner density to below this threshold to benefit woodland birds, but consistent monitoring and reporting would support better evaluation of effectiveness and correlates of success.

Abstract The new global biodiversity framework (GBF) being developed under the Convention on Biological Diversity must drive action to reverse the ongoing decline of the Earth's biodiversity. Explicit, measurable goals that specify the outcomes we want to achieve are needed to set the course for this action. However, the current draft goals and targets fail to set out these clear outcomes. We argue that distinct outcome goals for species, ecosystems, and genetic diversity are essential and should specify net outcomes required for each. Net outcome goals such as “no net loss” do, however, have a controversial history, and loose specification can lead to perverse outcomes. We outline seven general principles to underpin net outcome goal setting that minimize risk of such perverse outcomes. Finally, we recommend inclusion of statements of impact in action targets that support biodiversity goals, and we illustrate the importance of this with an example from the draft GBF action targets. These modifications would help reveal the specific contribution each action would make to achieving the outcome goals and provide clarity on whether the successful achievement of action targets would be adequate to achieve the outcome goals and, in turn, the 2050 vision: living in harmony with nature.

A key obstacle to wildlife conservation is a scarcity of funding. A recent paper [Courchamp, F., Jaric, I., Albert, C., Meinard, Y., Ripple, W. J., and Chapron, G. (2018). The paradoxical extinction of the most charismatic animals. PLoS Biol. 16:e2003997. doi: 10.1371/journal.pbio.2003997] illustrates how for-profit businesses' widespread use of threatened wildlife imagery could create complacency in the public about their conservation. A wildlife imagery royalty, whereby businesses that use threatened wildlife in their marketing pay a small percentage of their sales to the conservation of those species could be revolutionary for conservation funding. However, businesses are not currently compelled to support the protection of the species espoused in their products. We build upon the arguments presented by recent publications [Good, C., Burnham, D., and Macdonald, D. W. (2017). A cultural conscience for conservation. Animals 7:52. doi: 10.3390/ani7070052; Courchamp, F., Jaric, I., Albert, C., Meinard, Y., Ripple, W. J., and Chapron, G. (2018). The paradoxical extinction of the most charismatic animals. PLoS Biol. 16:e2003997. doi: 10.1371/journal.pbio.2003997] to explore limitations and a number of key pathways that may help bring a wildlife imagery royalty to fruition.

Abstract 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 Evaluating the effectiveness of management actions for threatened species recovery is critical for adaptive management. However, decision makers frequently lack the resources and time to develop data‐driven models for rigorous monitoring and evaluation. Expert knowledge can be useful in such situations, but can be challenging to translate into specific expectations about system responses. We describe a case study of the Saving Our Species program in New South Wales, Australia, showing how an integrated process drawing from structured decision making, conceptual modeling and structured expert elicitation can help species' managers formalize how a species is expected to respond to management over time and the assumptions about the mechanisms driving that response. The process described uses step‐by‐step guidelines to assist managers in defining the scope, documenting factors that influence outcomes and identifying indicators and target values for adaptive management plans. This case study demonstrates a robust, yet practical process for estimating species response to site management in situations where empirical monitoring data is absent or incomplete. In doing so it provides a useful tool that helps species' managers in data poor situations to take a more evidence‐informed approach to conservation.

Abstract African lions are declining across much of their range, yet robust measures of population densities remain rare. The Queen Elizabeth Conservation Area (QECA; 2,400 km2) in East Africa's Albertine Rift has potential to support a significant lion population. However, QECA lions are threatened, and information on the status of lions in the region is lacking. Here, we use a spatially explicit search encounter approach to estimate key population parameters of lions in the QECA. We then compare home range sizes estimated from our models to those from a radio‐collaring study implemented a decade earlier. We recorded 8,243.5 km of search effort over 93 days, detecting 30 individual lions (16 female and 14 male) on 165 occasions at a rate of 2 lion detections/100 km2. Lion density in the QECA was 2.70 adult lions/100 km2 (SD = 0.47), while mean abundance was 71 individuals (SD = 11.05). Worryingly, the movement parameter for male lions was 3.27 km and 2.22 km for females, suggesting > 400%, and > 100% increases in home range size, respectively, compared to a decade earlier. Sex ratio of lions in the QECA was lower (1 male: 0.75 females), when compared to a previously published review (mean = 1:2.33). The large movements and skewed sex ratios we report on in this paper are likely a result of human‐driven prey depletion. Our results suggest lions in the QECA are in a precarious state, and the lion densities are significantly lower than what they could be. As lions are under pressure throughout much of Africa, our study presents the utility of a census technique that could be used elsewhere as an early warning of lion declines.

Abstract 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 Loss of habitats or ecosystems arising from development projects (e.g., infrastructure, resource extraction, urban expansion) are frequently addressed through biodiversity offsetting. As currently implemented, offsetting typically requires an outcome of “no net loss” of biodiversity, but only relative to a baseline trajectory of biodiversity decline. This type of “relative” no net loss entrenches ongoing biodiversity loss, and is misaligned with biodiversity targets that require “absolute” no net loss or “net gain.” Here, we review the limitations of biodiversity offsetting, and in response, propose a new framework for compensating for biodiversity losses from development in a way that is aligned explicitly with jurisdictional biodiversity targets. In the framework, targets for particular biodiversity features are achieved via one of three pathways: Net Gain, No Net Loss, or (rarely) Managed Net Loss. We outline how to set the type (“Maintenance” or “Improvement”) and amount of ecological compensation that is appropriate for proportionately contributing to the achievement of different targets. This framework advances ecological compensation beyond a reactive, ad‐hoc response, to ensuring alignment between actions addressing residual biodiversity losses and achievement of overarching targets for biodiversity conservation.

Habitat loss is driving the extirpation of fauna across Earth. Many species are now absent from vast areas where they once occurred in inhabited continents, yet we do not have a good understanding of the extent to which different species have been locally extirpated, nor the degree to which range contractions and habitat loss has contributed to this local extirpation. Here, for the first time, we use a combination of scientific literature, historical sources, spatial data, and expert elicitation to map the past extent of potential habitats, and changes thereto, of 72 of Australia’s most imperiled terrestrial birds. By comparing the area of potential habitat within the past and current ranges of these taxa, we quantify the extent over which each of Australia’s threatened terrestrial birds have likely been extirpated and assess the amount and configuration of potential habitat that remains. Our results show that since 1750 (before European colonization), at least one extant taxon of threatened bird has disappeared from over 530 million hectares (69%) of Australia, through both range contractions and loss of potentially suitable habitat (noting these are not mutually exclusive phenomena). Ten taxa (14%) have likely been extirpated from >99% of their past potential habitat. For 56 taxa (78%), remaining habitat within their current potential habitats has become fragmented. This research paints a sobering picture of the extent of local extirpation of threatened birds from much of Australia over a 250 years time period. By mapping and quantifying this loss, these findings will help refine scientific understanding about the impact of habitat removal and other pervasive threats that are driving this observed extirpation.

Abstract 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 The popularity of bioacoustics for threatened species monitoring has surged. Large volumes of acoustic data can be collected autonomously and remotely with minimal human effort. The approach is commonly used to detect cryptic species and, more recently, to estimate abundance or density. However, the potential for conservation‐relevant information to be derived from acoustic signatures associated with particular behavior is less well‐exploited. Animal vocal behavior can reveal important information about critical life history events. In this study, we argue that the overlap of the disciplines of bioacoustics, vocal communication, and conservation behavior—thus, “acoustic conservation behavior”—has much to offer threatened species monitoring. In particular, vocalizations can serve as indicators of behavioral states and contexts that provide insight into populations as it relates to their conservation. We explore the information available from monitoring species' vocalizations that relate to reproduction and recruitment, alarm and defense, and social behavior, and how this information could translate into potential conservation benefits. While there are still challenges to processing acoustic data, we conclude that acoustic conservation behavior may improve threatened species monitoring where vocalizations reveal behaviors that are informative for management and decision‐making.

Abstract Compensation policies seek to counterbalance biodiversity losses caused by development; however, their effectiveness is rarely tested. We examined U.S. Species Conservation Banks (SCBs) in California, a compensation program initiated 30 years ago. We quantified the effect of 59 SCBs (15,350 ha) on habitat extent using statistical matching methods. SCBs averted a small, yet significant, amount of habitat loss (62 ha) between 2001 and 2011. However, unexpectedly, SCBs also averted significant habitat gains (1,424 ha). It is not possible to determine if losses averted by SCBs equaled losses caused by development for which credits were sold (because records of the latter do not exist), but estimated averted gains were 35 times greater than averted losses. To improve practice, SCBs must be designed to achieve outcomes that are additional and avoid crowding out other programs incentivizing statewide conservation goals.

Matrix land-use intensification is a relatively recent and novel landscape change that can have important influences on the biota within adjacent habitat patches. While there are immediate local changes that it brings about, the influences on individual animals occupying adjacent habitats may be less evident initially. High-intensity land use could induce chronic stress in individuals in nearby remnants, leading ultimately to population declines. We investigated how physiological indicators and body condition measures of tropical forest-dependent birds differ between forest adjacent to surface mining sites and that near farmlands at two distances from remnant edge in southwest Ghana. We used mixed effects models of several condition indices including residual body mass and heterophil to lymphocyte (H/L) ratios (an indicator of elevated chronic stress) to explore the effect of matrix intensity on forest-dependent passerines classed as either sedentary area-sensitive habitat specialists or nomadic generalists. Individual birds occupying tropical forest remnants near surface mining sites were in poorer condition, as indicated by lower residual body mass and elevated chronic stress, compared to those in remnants near agricultural lands. The condition of the sedentary forest habitat specialists white-tailed alethe, Alethe diademata and western olive sunbird, Cyanomitra obscura was most negatively affected by high-intensity surface mining land-use adjacent to remnants, whereas generalist species were not affected. Land use intensification may set in train a new trajectory of faunal relaxation beyond that expected based on habitat loss alone. Patterns of individual condition may be useful in identifying habitats where species population declines may occur before faunal relaxation has concluded.

Conversion of farmland land-use matrices to surface mining is an increasing threat to the habitat quality of forest remnants and their constituent biota, with consequences for ecosystem functionality. We evaluated the effects of matrix type on bird community composition and the abundance and evenness within avian functional groups in south-west Ghana. We hypothesized that surface mining near remnants may result in a shift in functional composition of avifaunal communities, potentially disrupting ecological processes within tropical forest ecosystems. Matrix intensification and proximity to the remnant edge strongly influenced the abundance of members of several functional guilds. Obligate frugivores, strict terrestrial insectivores, lower and upper strata birds, and insect gleaners were most negatively affected by adjacent mining matrices, suggesting certain ecosystem processes such as seed dispersal may be disrupted by landscape change in this region. Evenness of these functional guilds was also lower in remnants adjacent to surface mining, regardless of the distance from remnant edge, with the exception of strict terrestrial insectivores. These shifts suggest matrix intensification can influence avian functional group composition and related ecosystem-level processes in adjacent forest remnants. The management of matrix habitat quality near and within mine concessions is important for improving efforts to preserveavian biodiversity in landscapes undergoing intensification such as through increased surface mining.

Human-induced biotic homogenization resulting from landscape change and increased competition from widespread generalists or 'winners', is widely recognized as a global threat to biodiversity. However, it remains unclear what aspects of landscape structure influence homogenization. This paper tests the importance of interspecific competition and landscape structure, for the spatial homogeneity of avian assemblages within a fragmented agricultural landscape of eastern Australia. We used field observations of the density of 128 diurnal bird species to calculate taxonomic and functional similarity among assemblages. We then examined whether taxonomic and functional similarity varied with patch type, the extent of woodland habitat, land-use intensity, habitat subdivision, and the presence of Manorina colonies (a competitive genus of honeyeaters). We found the presence of a Manorina colony was the most significant factor positively influencing both taxonomic and functional similarity of bird assemblages. Competition from members of this widespread genus of native honeyeater, rather than landscape structure, was the main cause of both taxonomic and functional homogenization. These species have not recently expanded their range, but rather have increased in density in response to agricultural landscape change. The negative impacts of Manorina honeyeaters on assemblage similarity were most pronounced in landscapes of moderate land-use intensity. We conclude that in these human-modified landscapes, increased competition from dominant native species, or 'winners', can result in homogeneous avian assemblages and the loss of specialist species. These interacting processes make biotic homogenization resulting from land-use change a global threat to biodiversity in modified agro-ecosystems.