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Humanity is on a pathway of unsustainable loss of the natural systems upon which we, and all life, rely. To date, global efforts to deliver internationally-agreed goals to reduce carbon emissions, halt biodiversity loss, and retain essential ecosystem services, have been poorly integrated. All these goals rely in part on preserving natural (e.g. native, largely unmodified) and semi-natural (e.g. under some form of low intensity/sustainable human use) forests, woodlands and grasslands. Here, we show how to unify these goals by empirically deriving spatially explicit, quantitative area-based targets for the retention of natural and semi-natural (e.g. native) terrestrial vegetation. We found that at least 67 million km

Environmental policies that require native vegetation conservation can be challenging to implement, especially in productive agricultural landscapes. In Brazil, the Brazilian Native Vegetation Protection Law mandates ‘Legal Reserves’, protected native vegetation that landowners must retain on their properties. If landowners do not have the required minimum amount of native vegetation on their properties (the Legal Reserve ‘target’), they must either restore vegetation on the same property to meet the target, or compensate by protecting existing vegetation or restoring it on another property, ideally in ecologically equivalent areas. Here, we evaluate how different strategies (on-site/off-site protection and/or restoration), and different requirements for ecological equivalence when off-site strategies are used, affect the ability to achieve Legal Reserve targets, while minimising the need to restore native vegetation on productive farmland. We used a novel iterative tool to build scenarios that reflect different combinations of strategies to meet the minimum conservation target under different requirements for ecological equivalence, and compared their ability to achieve the target and their likely cost. The Atlantic Forest was the only biome where it was not possible to achieve the Legal Reserve target by protection of existing native vegetation, even when ecological equivalence rules were relaxed. As a consequence, vegetation restoration is required in this biome. Directing this required restoration to pasturelands that are less-suitable for agriculture allowed the target to be achieved in all states of Brazil, as long as only minimal ecological equivalence was required; however, for most states, the need to restore native vegetation on productive areas on farmlands could still be avoided while requiring medium to high ecological equivalence. These findings show the potential for moderate ecological equivalence to be achieved across most of Brazil in a cost-effective way and without impairing productive lands when seeking to meet the Legal Reserve targets.

With the intention of securing industry-free land and seascapes, protecting wilderness entered international policy as a formal target for the first time in the zero draft of the Post-2020 Global Biodiversity Framework under the Convention on Biological Diversity. Given this increased prominence in international policy, it is timely to consider the extent to which the construct of wilderness supports global conservation objectives. We evaluated the construct by overlaying recently updated cumulative human pressure maps that offer a global-scale delineation of industry-free land as wilderness with maps of carbon stock, species richness, and ground travel time from urban centers. Wilderness areas took variable forms in relation to carbon stock, species richness, and proximity to urban centers, where 10% of wilderness areas represented high carbon and species richness, 20% low carbon and species richness, and 3% high levels of remoteness (48 h), carbon, and species richness. Approximately 35% of all remaining wilderness in 2013 was accessible in24 h of travel time from urban centers. Although the construct of wilderness can be used to secure benefits in specific contexts, its application in conservation must account for contextual and social implications. The diverse characterization of wilderness under a global environmental conservation lens shows that a nuanced framing and application of the construct is needed to improve understanding, communication, and retention of its variable forms as industry-free places.Formas de las Áreas Silvestres y sus Implicaciones para las Políticas y la Conservación Mundial Resumen Con la intención de asegurar paisajes terrestres y marinos libres de la industria, la protección de las áreas silvestres entró a la política internacional por primera vez como un objetivo formal en el primer borrador del Marco de Trabajo para la Biodiversidad Mundial Post-2020 bajo el Convenio sobre la Diversidad Biológica. Con este incremento en la presencia dentro de la política internacional, es oportuno considerar el grado al que el concepto de área silvestre ayuda a los objetivos de conservación mundial. Evaluamos este concepto mediante la superposición de mapas de la presión humana acumulada recientemente actualizados que brindan una definición a escala mundial de las tierras libres de industria con mapas del stock de carbono, riqueza de especies y el tiempo de traslado terrestre desde los centros urbanos. Las áreas silvestres mostraron formas variables con respecto al stock de carbono, la riqueza de especies y la cercanía a los centros urbanos, de las cuales el 10% representó una elevada riqueza de especies y presencia de carbono, el 20% una baja riqueza de especies y presencia de carbono y el 3% una elevada lejanía (48 horas), presencia de carbono y riqueza de especies. Aproximadamente el 35% de todas las áreas silvestres en 2013 era accesible en24 horas de traslado desde los centros urbanos. Aunque el concepto de áreas silvestres puede usarse para garantizar beneficios en contextos específicos, su aplicación en la conservación debe considerar las implicaciones contextuales y sociales. La caracterización diversa de las áreas silvestres bajo el lente de la conservación ambiental mundial muestra que un encuadre matizado y la aplicación de este concepto son necesarios para aumentar el conocimiento, la comunicación y la retención de sus formas variables como lugares libres de industria.

Some conservation prioritization methods are based on the assumption that conservation needs overwhelm current resources and not all species can be conserved; therefore, a conservation triage scheme (i.e., when the system is overwhelmed, species should be divided into three groups based on likelihood of survival, and efforts should be focused on those species in the group with the best survival prospects and reduced or denied to those in the group with no survival prospects and to those in the group not needing special efforts for their conservation) is necessary to guide resource allocation. We argue that this decision‐making strategy is not appropriate because resources are not as limited as often assumed, and it is not evident that there are species that cannot be conserved. Small population size alone, for example, does not doom a species to extinction; plants, reptiles, birds, and mammals offer examples. Although resources dedicated to conserving all threatened species are insufficient at present, the world's economic resources are vast, and greater resources could be dedicated toward species conservation. The political framework for species conservation has improved, with initiatives such as the UN Sustainable Development Goals and other international agreements, funding mechanisms such as The Global Environment Facility, and the rise of many nongovernmental organizations with nimble, rapid‐response small grants programs. For a prioritization system to allow no extinctions, zero extinctions must be an explicit goal of the system. Extinction is not inevitable, and should not be acceptable. A goal of no human‐induced extinctions is imperative given the irreversibility of species loss., Article impact statement: Conservation triage is not necessary for species conservation. Adequate resources exist; even species with small populations can recover.

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 km2 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. An assessment of the habitat of native vertebrate species burnt by the 2019–2020 Australian mega-fires shows that 70 taxa were severely affected.

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.

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 Conven-tion 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.

In 2010, Parties to the Convention on Biological Diversity (CBD) adopted the Strategic Plan for Biodiversity 2011–2020 to address the loss and degradation of nature. Subsequently, most biodiversity indicators continued to decline. Nevertheless, conservation actions can make a positive difference for biodiversity. The emerging Post-2020 Global Biodiversity Framework has potential to catalyze efforts to ‘bend the curve’ of biodiversity loss. Thus, the inclusion of a goal on species, articulated as Goal B in the Zero Draft of the Post-2020 Framework, is essential. However, as currently formulated, this goal is inadequate for preventing extinctions, and reversing population declines; both of which are required to achieve the CBD’s 2030 mission. We contend it is unacceptable that Goal B could be met while most threatened species deteriorated in status and many avoidable species extinctions occurred. We examine the limitations of the current wording and propose an articulation with robust scientific basis. A goal for species that strives to end extinctions and recover populations of all species that have experienced population declines, and especially those at risk of extinction, would help to align actors towards the transformative actions and interventions needed for humans to live in harmony with nature.

Thresholds in the relationship between species richness and natural land cover can inform landscape-level vegetation protection and restoration targets. However, landscapes differ considerably in composition and other environmental attributes. If the effect of natural land cover on species richness depends on (i.e., interacts with) these attributes, and this affects the value of thresholds in this relationship, such dependencies must be considered when using thresholds to guide landscape management. We hypothesized that the amount of natural land cover at which a threshold occurs would differ in predictable ways with particular anthropogenic, abiotic, and biotic attributes of landscapes. To test this, we related woodland bird species richness in 251 landscapes, each 100 km, to natural land cover in south-east Australia. We compared the fit of exponential and threshold models of the richness–natural land cover relationship, focussing on the extent of natural land cover at which thresholds presented among landscapes that differed in matrix land use intensity, heterogeneity, productivity, and the prevalence of strong biotic interactors. We used linear mixed modelling to examine how interactions between natural land cover and the various landscape attributes affected the fit of models of species richness. Threshold models of the richness–natural land cover relationship were always a better fit than exponential models. Threshold values did not vary consistently with specific landscape attributes, with the exception of landscapes that were classified by the prevalence of strong biotic interactors (hypercompetitive native birds of the genus Manorina). Natural land cover had a more positive effect on species richness in landscapes when Manorina prevalence was higher. This positive interaction provided the biggest improvement in explanatory power of models of species richness. Synthesis and applications. While we detected an interaction between Manorina prevalence and the area of natural land cover, generalities relating to the underlying nature of thresholds in the richness–natural land cover relationship remain elusive. Complex interactions, relating to various landscape attributes and associated ecological processes, likely underpin variation in threshold values. Until these complexities are better understood, the use of thresholds for informing landscape management and conservation target setting should be approached with caution.

Humanity is on a pathway of unsustainable loss of the natural systems upon which we, and all life, rely. To date, global efforts to achieve internationally-agreed goals to reduce carbon emissions, halt biodiversity loss, and retain essential ecosystem services, have been poorly integrated. However, these different goals all rely on preserving natural ecosystems. Here, we show how to unify these goals by empirically deriving spatially-explicit, quantitative area-based targets for the retention of natural terrestrial ecosystems. We found that at least 67 million km2of Earth’s natural terrestrial ecosystems (~79% of the area remaining) require retention – via a combination of strict protection but more prominently through sustainably managed land use regimes complemented by restoration actions – to contribute to biodiversity, climate, soil and freshwater objectives under four United Nations’ Resolutions. This equates to retaining natural ecosystems across ~50% of the total terrestrial (excluding Antarctica) surface of Earth. Our results show where retention efforts could be focussed to contribute to multiple goals simultaneously. The retention targets concept that we present explicitly recognises that such management can and should co-occur alongside and be driven by the people who live in and rely on places where natural and semi-natural ecosystems remain on Earth.

Tropical forests harbor most of the planet’s terrestrial biodiversity, and their loss means destruction of habitat for many species. Tropical deforestation continues at high rates in many regions, but it is often reported only in terms of area lost or its impacts on high-profile threatened species. We estimated the impact of both past and projected future deforestation on habitat extent for the entire assemblage of forest-dependent birds across Colombia, the country with more bird species than any other. Of the 550 forest-dependent species analysed, Almost all (n=536; 96.5%) had lost habitat, and 18% had lost at least half of their habitat by 2015. We used the recently developed Loss Index (LI) to capture the severity of habitat loss for the forest bird assemblage, discovering that the current LI for Colombia is 35, which means 35% of bird species have lost at least 35% of their habitat. The national LI for Colombia is projected to rise to 43 by 2040 if recent forest loss trends continue. There were large regional differences; Caribe had an LI of 82 while for the Pacific it was 14. A threat assessment for the regionally endemic species in the country showed that 12 (30%) of the species that are projected to lose 50% or more of their historical habitat by 2040 are not currently classified as threatened by the IUCN, suggesting that there are many species that are not listed but that face an imminent extinction threat from habitat loss. This extensive habitat depletion affecting entire species assemblages has significant implications for tropical forest ecosystems, and risks eroding ecosystem function and ecosystem service provision.

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.

Urgent action is required to ‘bend the curve’ on biodiversity loss. However, the ‘species goal’ (Goal B) unveiled in the recently released Zero Draft of the Post-2020 Global Biodiversity Framework (GBF) is inadequate for mobilizing conservation actions to achieve the outcomes required to halt and reverse species declines. Here we examine the limitations of the goal as presented in the Zero Draft and propose a more ambitious goal for species. The conservation community must ensure that the species goal of the GBF captures what is actually needed from a species perspective for the Post-2020 Framework to achieve its 2030 mission “to put biodiversity on a path to recovery for the benefit of planet and people”, lest the mission be doomed from the start.

A global goal of no net loss of natural ecosystems or better has recently been proposed, but such a goal would require equitable translation to country-level contributions. Given the wide variation in ecosystem depletion, these could vary from net gain (for countries where restoration is needed), to managed net loss (in rare circumstances where natural ecosystems remain extensive and human development imperative is greatest). National contributions and international support for implementation also must consider non-area targets (for example, for threatened species) and socioeconomic factors such as the capacity to conserve and the imperative for human development.

Offsetting—trading losses in one place for commensurate gains in another—is a tool used to mitigate environmental impacts of development. Biodiversity and carbon are the most widely used targets of offsets; however, other ecosystem services are increasingly traded, introducing new risks to the environment and people. Here, we provide guidance on how to “trade with minimal trade-offs”— i.e. how to offset impacts on biodiversity without negatively affecting ecosystem services and vice versa. We briefly survey the literature on offsetting biodiversity, carbon and other ecosystem services, revealing that each subfield addresses unique issues (often overlooking those raised by others) and rarely assesses potential trade-offs. We discuss key differences between offsets that trade biodiversity and those that trade ecosystem services, conceptualise links between these different targets in an offsetting context and describe three broad approaches to manage potential trade-offs. We conclude by proposing a research agenda to strengthen the outcomes of offsetting policies that are emerging internationally. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13280-019-01245-3) contains supplementary material, which is available to authorized users.

Market-like mechanisms for biodiversity offsetting have emerged globally as supposedly cost-effective approaches for mitigating the impacts of development. In reality, offset buyers have commonly found that required credits are scarce and/or expensive. One response has been to seek improved market functionality, increasing eligible offset supply by allowing greater flexibility in the offset trading rules. These include increasing the size of geographical trading areas and expanding out-of-kind trades (‘geographical’ and ‘ecological’ flexibility). We summarise the arguments for and against flexibility, ultimately arguing that increasing flexibility undermines the achievement of No Net Loss (or Net Gain) of biodiversity where high-quality governance is lacking. We argue expanding out-of-kind trading often increases the pool of potentially eligible offsets with limited conservation justification. This interferes with vital information regarding the scarcity of the impacted biodiversity feature, thereby disincentivising impact avoidance. When a biodiversity feature under threat of development is scarce, expensive offsets are an essential feature of the economics of offsetting which communicate that scarcity, not a problem to be regulated away. We present examples where increasing ecological flexibility may be justifying the loss of conservation priorities. We also discuss how increasing geographical flexibility might compromise the additionality principle. We highlight alternative mechanisms for enhancing offset supply without the risks associated with increasing flexibility, including reducing policy uncertainty and improving engagement and awareness to increase landholder participation. Although there are legitimate reasons for increasing offsetting flexibility in some specific contexts, we argue that the biodiversity risks are considerable, and potentially undermine ‘no net loss’ outcomes.

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.

Australia has one of the worst extinction rates of any nation, yet there has been little assessment of the effect of its flagship environmental legislation, the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), to prevent species extinction. By coupling remotely sensed forest and woodland data with the distributions of 1,638 terrestrial threatened species, terrestrial migratory species, and threatened ecological communities, we quantified the loss of potential habitat and communities since the EPBC Act came into force in 2000. We found that over 7.7 million ha of potential habitat and communities were cleared in the period 2000–2017. Of this clearing, over 93% was not referred to the Federal Government for assessment, meaning the loss was not scrutinized under the EPBC Act. While 1,390 (84%) species suffered loss, Mount Cooper striped skink, Keighery's macarthuria, and Southern black‐throated finch lost 25, 23, and 10% of potential habitat, respectively. Iconic Australian species, such as koala, also lost ~1 million ha (2.3%) of potential habitat. Our analysis showed that the EPBC Act is ineffective at protecting potential habitat for terrestrial threatened species, terrestrial migratory species, or threatened ecological communities. We recommend that when scientifically determinable, critical habitat is demarcated for listed species and communities, which provides absolute protection that is enforced, monitored, and investigated by the regulator. Without a fundamental change in how environmental law is enforced, Australia faces an increasing extinction rate.

We describe current approaches that evaluate how the influence of species traits on the relationship between environmental variables and ecological responses varies among scales (i.e. the scale-dependent role of traits). We quantify which traits and ecological responses have been assessed, and discuss the main challenges associated with quantifying the scale-dependent effect of traits. We identify three main approaches used to evaluate the scale-dependent role of traits, based on whether 1) traits are used as predictors or responses, 2) intraspecific variation in single traits is considered, or 3) trait diversity indices are used. Our review identifies several gaps that include the following: 1) evidence of the scale-dependent role of traits is biased towards studies of plants; 2) we lack evidence of whether the traits of interacting species groups are consistently related across spatial scales; and 3) interactions between species traits and landscape structure are usually ignored. The explicit inclusion of landscape structure effects in trait-based approaches at multiple scales will benefit the integration of approaches from community ecology and landscape ecology. This is important for describing the mechanisms that operate simultaneously across scales and for predicting the impact of landscape change on a broad range of ecological responses, including species diversity and interspecific interactions.

Native vegetation extent is often a proxy for habitat area in studies of human-modified landscapes. However, the loss and retention of native vegetation is rarely random among landscapes. Instead, the extent of native vegetation in landscapes may be correlated with abiotic factors, thereby obscuring or distorting relationships between ecological phenomena and area. We asked: (1) how has the potential for non-random vegetation loss to confound area effects been addressed in the landscape ecology literature? (2) Are consistent patterns of non-random vegetation loss and retention evident from modified regions of two countries? We reviewed 118 papers that related area to an ecological response, to determine whether potential biases associated with non-random vegetation loss and retention were considered. We then analysed ~18,000 100 km2 landscape units in Australia and South Africa to identify how different abiotic factors correlate with the extent of native vegetation retained in those landscapes. Only 21% of the studies we reviewed explicitly or implicitly considered spatial biases in vegetation clearing. Yet, across modified regions of Australia and South Africa, landscape-scale native vegetation extent was consistently and often strongly related to abiotic factors, particularly soil properties and topographic variability. Patterns of vegetation clearing and retention commonly reflect underlying abiotic heterogeneity. These biases, which are infrequently highlighted in studies focussing on area effects, have implications for how we assess the importance of vegetation extent for species and assemblages. Failure to account for correlates of vegetation extent risks erroneous area-based conservation prescriptions in human-modified environments.

A global goal of no net loss of natural ecosystems or better has recently been proposed, but such a goal would require equitable translation to country-level contributions. Given the wide variation in ecosystem depletion, these could vary from net gain (for countries where restoration is needed), to managed net loss (in rare circumstances where natural ecosystems remain extensive and human development imperative is greatest). National contributions and international support for implementation also must consider non-area targets (for example, for threatened species) and socioeconomic factors such as the capacity to conserve and the imperative for human development.

Habitat destruction is among the greatest threats facing biodiversity, and it affects common and threatened species alike. However, metrics for communicating its impacts typically overlook the nonthreatened component of assemblages. This risks the loss of habitat going unreported for species that comprise the majority of assemblages. We adapted a widely used measure for summarizing researcher output (the h index) to provide a metric that describes natural habitat loss for entire assemblages, inclusive of threatened and nonthreatened species. For each of 447 Australian native terrestrial bird species, we combined information on their association with broad vegetation groups with distributional range maps to identify the difference between the estimated pre-European and current extents of potential habitat, defined as vegetation groups most closely associated with each species. From this, we calculated the loss index (LI), which revealed that 30% of native birds have each lost at least 30% of their potential natural habitat (LI = 30). At the subcontinental scale, LIs ranged from 15 in arid Australia to 61 in the highly transformed southeastern part of the country. Different subcomponents of the assemblage had different LI values. For example, Australia's parrots (n = 52 species) had an LI of 38, whereas raptors (n = 32 species) had an LI of 25. The LI is simple to calculate and can be determined using readily available spatial information on species distributions, native vegetation associations, and human impacts on natural land cover. This metric, including the curves used to deduce it, could complement other biodiversity indices if it is used for regional and global biodiversity assessments that compare the status of natural habitat extent for assemblages within and among nations, monitor changes through time, and forecast future changes to guide strategic land-use planning. The LI is an intuitive tool that can be used to summarize and communicate how human actions affect whole assemblages, not just threatened species.Una Medida Compuesta de la Pérdida del Hábitat para Ensamblajes Enteros de Especies Resumen La destrucción del hábitat está entre las principales amenazas para la biodiversidad, además de que afecta tanto a especies comunes como a las especies amenazadas. Sin embargo, las medidas para comunicar los impactos de esta destrucción generalmente ignoran al componente no amenazado de los ensamblajes de especies. Esto genera el riesgo de que la pérdida del hábitat pase desapercibida en el caso de las especies que conforman a la mayoría de los ensamblajes. Adaptamos una medida de uso amplio para resumir las contribuciones de los investigadores (el índice h) y así proporcionar una medida que describa la pérdida del hábitat para ensamblajes enteros, incluyendo a las especies amenazadas y a las no amenazadas. Para cada una de las 447 especies de aves terrestres nativas a Australia, combinamos la información sobre su asociación con grupos generales de vegetación con mapas de extensión de su distribución para identificar la diferencia entre la extensión estimada previa a la llegada de los europeos y la extensión actual de los hábitats potenciales, definidos como los grupos de vegetación asociados más cercanamente con cada especie. A partir de esto, calculamos el índice de pérdida (LI, en inglés), el cual reveló que el 30% de cada una de las aves nativas ha perdido al menos el 30% de su hábitat natural potencial (LI = 30). A escala subcontinental, los LI variaron desde 15 para las partes áridas de Australia, hasta 61 en la altamente transformada parte sureste del país. Los diferentes subcomponentes del ensamblaje tuvieron diferentes valores de LI. Por ejemplo, los loros australianos (n = 52 especies) tuvieron un LI de 38, mientras que las aves rapaces (n = 32 especies) tuvieron un LI de 25. El LI es fácil de calcular y puede determinarse usando información espacial que ya se encuentra disponible, las asociaciones con la vegetación nativa y los impactos humanos sobre la cobertura natural del suelo. Esta medida, incluyendo las curvas que se usan para deducirla, podrían complementar otros índices de biodiversidad si se usa para evaluaciones de la biodiversidad regional y global, las cuales comparan el estado de la extensión del hábitat natural para ensamblajes dentro y entre las naciones, monitorean cambios a través del tiempo y pronostican cambios futuros que guíen la planeación del uso de suelo estratégico. El LI es una herramienta intuitiva que puede usarse para resumir y comunicar cómo las acciones humanas afectan a ensamblajes enteros, no sólo a las especies amenazadas.生境破坏是生物多样性面临的最大威胁之一, 它同时影响着常见种和濒危种。然而, 对生境破坏影响的指标却常常忽略群落聚合体中的非濒危组分, 这有可能导致群落中大部分物种的生境丧失得不到报告。我们在常用的总结研究者产出 (h 指数) 方法的基础上, 创建了一个描述整个群落聚合体 (包括濒危和非濒危物种) 自然生境丧失的指标。利用这个方法, 我们将澳洲 447 种本土陆生鸟类所在的植被群信息与分布图相结合, 确定了它们在前欧洲时期和当前估计的潜在生境范围之间的差异, 其中对潜在生境的定义是那些与每个物种相关度最高的植被群。我们用这个模型计算了丧失指数, 结果显示有 30%的本土鸟类分别丧失了至少 30%的潜在自然生境 (丧失指数为 30) 。在次大陆尺度上, 丧失指数介于 15 (澳洲干旱地区) 到 61 (东南部高度改造生境) 之间。含有不同组分的群落聚合体有不同的丧失指数, 例如, 澳洲鹦鹉 (52 个物种) 的丧失指数为 38, 而猛禽 (32 个物种) 的丧失指数为 25。丧失指数计算简单, 可以利用现成的物种空间分布、原生植被群以及人类对自然土地覆盖的影响等信息。在比较国家内部或国家之间群落聚合体的自然生境情况、监测其随时间的变化, 及预测未来变化以指导土地利用战略规划时, 可以用丧失指数和用于估计指数的曲线作为其它生物多样性指标的补充, 以评估区域和全球生物多样性。丧失指数是一项直观的工具, 它可以用于总结和探讨人类行为对整个群落聚合体的影响, 而不仅限于濒危物种。 【翻译: 胡怡思; 审校: 聂永刚】.

As humanity’s demand for resources continues to rise and productive arable lands become increasingly scarce, many of Earth’s remaining intact regions are at heightened risk of destruction from agricultural development. In situations where agricultural expansion is inevitable, it is important to manage intact landscape transformation so that impacts on environmental values are minimised. Here, we present a novel, spatially explicit, land use planning framework that addresses the decision making needed to account for different, competing economic-environment objectives (agricultural production value, biodiversity conservation, ecosystem service retention) when land use change is inevitable within an intact landscape. We apply our framework to the globally significant savannahs of the Orinoquia (Colombia), which in a post-conflict era is under increased agricultural development pressure. We show that while negative environmental impacts can be reduced through planning, the total area of land converted to agriculture is the unavoidable principal driver of biodiversity and ecosystem service loss. We therefore identify planning solutions that perform well across all objectives simultaneously, despite trade-offs among them. When 15%, 20%, 30% and 40% of the study area is allowed to be converted to agriculture, on average planning can improve species persistence and ecosystem service retention by up to 16%, 15%, 12%, and 9%, respectively, when compared to agricultural-focused solutions. Development in the region so far has had an unnecessarily large impact on environmental objectives due to a lack of effective land use planning, creating an ‘opportunity debt’. Our study provides an evidence base to inform proactive planning and the development of environmentally sensible agricultural development policy and practice in the region. This framework can be used by stakeholders to achieve agriculture expansion goals and maximise economic profit while minimising impacts on the environment in the Orinoquia, or any relatively intact region that is being developed.

Ambitious targets for the retention — not just formal protection — of nature are urgently needed to conserve biodiversity and to maintain crucial ecosystem services for humanity.

Vegetation clearing results in the loss of species from landscapes. Indeed, the area of remaining native vegetation is an important determinant of species richness in human-modified mosaics. Of interest to ecologists and landscape managers is the effect of areamthat is, how the number of species a landscape supports changes with the amount of native vegetation, as revealed by the shape and functional form of the species-area relationship. Understanding this is vital for guiding conservation interventions such as setting limits to vegetation clearing or establishing revegetation targets. Crucially though, it is not only vegetation area that affects patterns of species richness at the landscape levelmso do environmental attributes such as soil properties and topography. Complicating the matter is the fact that these attributes tend to be correlated with landscape-level vegetation area, because humans preferentially remove vegetation from landscapes suited to land uses such as agriculture. However, this interplay between vegetation area, other landscape attributes, and biased patterns of vegetation loss/retention is infrequently considered in landscape-level species-area analyses. If unaccounted for, these confounding factors may result in erroneous interpretations of the effect of area, leading to suboptimal management actions. The aim of this thesis was to examine how attributes of landscapes affect the relationship between species richness and vegetation area. Through four specific research questions, I explored in detail the hypothesis that attributes of human-modified landscapes that bias vegetation clearing also interact with vegetation area to produce landscape-specific area effects on species richness. First, I quantified correlates of vegetation clearing/retention in two regions of the southern hemisphere, and reviewed the literature to determine how often, and in what ways, biased clearing patterns are accounted for in studies relating vegetation area to an ecological response. I demonstrated that soil properties and range in elevation are reliably associated with the amount of remaining native vegetation across ~18,000 100 km2 landscapes in Australia and South Africa. Importantly though, I found that clearing biases were explicitly acknowledged in only 15 of the 118 reviewed studies. If the area of native vegetation in landscapes is a legacy of biased clearing, confounding factors like soil properties should be accounted for in analyses of area effects. Second, I explored the extent to which the effect of native vegetation area on species richness differed in 100 km2 landscapes categorised by attributes such as soil fertility, range in elevation or matrix land use. Using a case study of south-east Australian birds, I found that the shape of the species-area relationship varied substantially depending on whether landscapes were, for example, more- or less-topographically variable, or had higher or lower soil fertility. While threshold models depicting a point of sudden change in the effect of area emerged consistently, the amount of vegetation corresponding with observed thresholds differed considerably among landscape types. Therefore, aggregating and analysing species-area data from different landscape types is likely to misrepresent how species richness is affected by vegetation area. This will be exacerbated by clearing biases, because heavily cleared landscapes tend to be characterised by very different attributes to high cover landscapes. Third, I compared the effect of vegetation area on bird species richness at three scales of analysis (landscapes of 25 km2, 100 km2, 400 km2) for two regions of south-east Australia. When data for the entire study extent were analysed, a remarkable degree of scale-invariance was observedmnamely, a threshold relationship with a change-point at approximately 30% vegetation cover. However, when data were analysed for two regional subsets of the overall dataset, the effect of vegetation area, and the factors moderating this relationship, were scale-dependent. Given this finding, observed thresholds can only reliably be used to guide landscape management at the scale and in the region where the relationship was observed. Finally, I evaluated the implications of accounting for clearing biases when using species-area relationships to guide conservation, focussing on a region of Australia undergoing rapid landscape transformation. I found that using observed thresholds from species-area models that do and do not account for landscape attributes yielded different outcomes for landscape-scale species richness conservation, given a scenario of future vegetation loss. Specifically, the number and location of landscapes that could be prioritised for conservation actions varied considerably depending on the species-area model used. This research demonstrates that the effect of area on species richness differs substantially as a function of the attributes of landscapes. Crucially, clearing biases underpinned by these same attributes can confound analyses of the species-area relationship. Accounting for landscape attributes will allow for a more rigorous understanding of how species richness varies among landscapes with different amounts of native vegetation. A robust appreciation of the effect of area will provide more certainty around how much vegetation needs to be managed (i.e. protected, revegetated), and where this should occur among multiple landscapes, to avert the loss of, or enhance, landscape-scale species richness.

Previous approaches to indirect detection of koala presence have been proposed, however, the present paper identifies issues of bias, pellet detectability and over-analysis of information inherent in those prior techniques. We recommend an approach that reduces bias, can be consistently applied and enables information on presence of koalas Phascolarctos cinereus to be used to inform larger survey programs, ‘ground-truth’ predictive habitat mapping, etc. We describe a rapid assessment methodology based on indirect signs that provides a reproducible, statistically valid, time-efficient and resource-efficient protocol for determining the presence of this species. The application, advantages and limitations of this ‘koala rapid assessment method’ (KRAM) are discussed with reference to its role in the design of detailed and landscape scale P. cinereus surveys.