Equivalent biodiversity area: A novel metric for No Net Loss success in Brazil's changing biomes.

This study presents a new method to incorporate the No Net Loss (NNL) principle within corporate Environmental, Social, and Governance (ESG) frameworks. This principle aims to ensure that biodiversity losses from human activities are fully offset. In this context, we tackle two main challenges: managing epistemic uncertainties in environmental modeling and accurately assessing compensatory areas needed to replace lost habitats. Focusing on Brazil's diverse biomes, which are undergoing rapid changes, we highlight the role of expert opinion surveys in addressing the uncertainties of the InVEST Habitat Quality, a model that simulates changes in landscape integrity under different land use scenarios. Our analysis across three of Brazil's regions - Caatinga Semi-arid, Cerrado Savanna, and Atlantic Forest - leverages open-source data to reveal substantial habitat losses due to activities like wind farm development, mining, and intensive agriculture, leading to a widespread decline in habitat quality. We introduce the Equivalent Biodiversity Area (EBA) metric to support NNL and Net Gain of Biodiversity efforts, measured in hectares. Findings show a reduction in EBA across all studied areas, highlighting the need for effective compensation strategies. Such strategies should merge Legal Reserves and ecological restoration into ESG policies, encourage landholder collaboration, and align with larger environmental efforts, such as watershed revitalization and Biodiversity Credits markets.

Evaluating the impact of biodiversity offsetting on native vegetation.

Biodiversity offsetting is a globally influential policy mechanism for reconciling trade-offs between development and biodiversity loss. However, there is little robust evidence of its effectiveness. We evaluated the outcomes of a jurisdictional offsetting policy (Victoria, Australia). Offsets under Victoria's Native Vegetation Framework (2002-2013) aimed to prevent loss and degradation of remnant vegetation, and generate gains in vegetation extent and quality. We categorised offsets into those with near-complete baseline woody vegetation cover ("avoided loss", 2702 ha) and with incomplete cover ("regeneration", 501 ha), and evaluated impacts on woody vegetation extent from 2008 to 2018. We used two approaches to estimate the counterfactual. First, we used statistical matching on biophysical covariates: a common approach in conservation impact evaluation, but which risks ignoring potentially important psychosocial confounders. Second, we compared changes in offsets with changes in sites that were not offsets for the study duration but were later enrolled as offsets, to partially account for self-selection bias (where landholders enrolling land may have shared characteristics affecting how they manage land). Matching on biophysical covariates, we estimated that regeneration offsets increased woody vegetation extent by 1.9%-3.6%/year more than non-offset sites (138-180 ha from 2008 to 2018) but this effect weakened with the second approach (0.3%-1.9%/year more than non-offset sites; 19-97 ha from 2008 to 2018) and disappeared when a single outlier land parcel was removed. Neither approach detected any impact of avoided loss offsets. We cannot conclusively demonstrate whether the policy goal of 'net gain' (NG) was achieved because of data limitations. However, given our evidence that the majority of increases in woody vegetation extent were not additional (would have happened without the scheme), a NG outcome seems unlikely. The results highlight the importance of considering self-selection bias in the design and evaluation of regulatory biodiversity offsetting policy, and the challenges of conducting robust impact evaluations of jurisdictional biodiversity offsetting policies.

Evaluating the potential of biodiversity offsets to achieve net gain.

Evaluating the outcomes and tracking the trajectory of biodiversity offsets is essential to demonstrating their effectiveness as a mechanism to conciliate development and conservation. We reviewed the literature to determine the principles that should underpin biodiversity offset planning and the criteria for offset evaluation at the project level. According to the literature, the core principles of equivalence, additionality, and permanence are used as criteria to evaluate conservation outcomes of offsets. We applied the criteria to evaluate offsets of a large iron ore mining project in the Atlantic Forest in Brazil. We examined equivalence in terms of the amount of area per biodiversity value affected and fauna and flora similarity, additionality in terms of landscape connectivity, and permanence in terms of guarantees to ensure protection and restoration offsets lasting outcomes. We found an offset ratio (amount of affected area:offset area) of 1:1.8 for forests and 1:2 for grasslands. Ecological equivalence (i.e., similarity between affected and offset areas) was found for forested areas, but not for ferruginous rupestrian grasslands or for fauna. Landscape metrics showed that connectivity improved relative to the preproject situation as a result of locating restoration offsets in the largest and best-connected forest patch. Permanence of offsets was addressed by establishing covenants and management measures, but financial guarantees to cover maintenance costs after mine closure were lacking. Offsets should be equivalent in type and size, provide conservation outcomes that would not be obtained without them (additionality), and be lasting (permanence). To monitor and evaluate offsets, it is necessary to determine how well these 3 principles are applied in the planning, implementation, and maintenance of offsets. Achieving measurable conservation outcomes from offsets is a long-term endeavor that requires sustained management support, and is information intensive. Thus, offsets require ongoing monitoring and evaluation as well as adaptive management.

Evaluación del potencial de las compensaciones por biodiversidad para obtener ganancias netas Resumen La evaluación de resultados y el rastreo de la trayectoria de las compensaciones por biodiversidad son esenciales para demostrar su efectividad como mecanismo de conciliación entre el desarrollo y la conservación. Revisamos la literatura para determinar los principios que deberían sustentar los planes de compensación y los criterios para evaluarla a nivel de proyecto. Según la literatura, se usan los principios nucleares de equivalencia, adicionalidad y permanencia como criterio para evaluar los resultados de conservación de las compensaciones. Aplicamos este criterio para evaluar las compensaciones de un gran proyecto minero de mineral de hierro en el Bosque Atlántico de Brasil. Analizamos la equivalencia en términos de cantidad de área por valor de biodiversidad afectado y similitudes entre la flora y fauna; la adicionalidad en términos de conectividad de paisaje; y la permanencia en términos de las garantías que aseguran que las compensaciones tengan resultados longevos de restauración y protección. Descubrimos una proporción en las compensaciones (cantidad del área afectada:área de compensación) de 1:1.8 para los bosques y de 1:2 en los campos naturales. Encontramos equivalencias ecológicas (es decir, la similitud entre las áreas afectadas y las de compensación) para las áreas boscosas, pero no para los campos rupestres ferruginosos ni para la fauna. Las medidas del paisaje mostraron que la conectividad mejoró en relación a la situación previa al proyecto gracias a la ubicación de las compensaciones por restauración en los fragmentos de bosque más grandes y mejor conectados. Establecimos Contractos y medidas de manejo fueron establecidos la permanencia de las compensaciones, pero las garantías económicas para cubrir los costos de mantenimiento después del cierre de la mina no están suficientemente garantizadas. Las compensaciones deberían ser iguales en tipo y tamaño (equivalencia), proporcionar resultados de conservación que no se obtendrían en su ausencia (adicionalidad) y ser duraderas (permanencia). Se necesita determinar cómo se aplican estos tres principios en la planeación, implementación y mantenimiento de las compensaciones para poder monitorearlas. Si se quieren lograr resultados medibles de conservación, se necesita que el manejo cuente con un apoyo mantenido y a largo plazo que contenga con información intensiva. Por lo tanto, las compensaciones requieren un monitoreo y evaluación continua además del manejo adaptativo.

Exploring the risks and benefits of flexibility in biodiversity offset location in a case study of migratory shorebirds.

Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian-Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat-based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost-effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement.

Estudio de los riesgos y beneficios de la flexibilidad en la ubicación de compensación de la biodiversidad en el estudio de caso de aves costeras migratorias Resumen Las compensaciones de la biodiversidad buscan contrabalancear el impacto residual que tiene el desarrollo sobre las especies y los ecosistemas. Los documentos guía recomiendan explícitamente que las acciones de estas compensaciones estén ubicadas cerca del lugar del impacto debido al potencial elevado de que haya condiciones ecológicas similares, aunque ya hay propuestas de una mayor flexibilidad espacial. Analizamos las circunstancias bajo las cuales las compensaciones alejadas del lugar de impacto tendrían mayor probabilidad de lograr pérdidas netas nulas o de proporcionar mejores resultados ecológicos que las compensaciones cercanas al área de impacto. Aplicamos un modelo gráfico para las aves costeras migratorias en el corredor aéreo asiático-australasiático del este como estudio de caso para estudiar los problemas que surgen cuando se incorpora la flexibilidad espacial a la planeación de las compensaciones. Las compensaciones espacialmente flexibles pueden mitigar los impactos más efectivamente que las compensaciones locales; sin embargo, los riesgos que esto involucra pueden ser considerables. En nuestro estudio de caso hubo datos insuficientes para concluir contundentemente sobre la efectividad y equivalencia de las compensaciones basadas en los hábitats distantes para las aves costeras migratorias. Las decisiones en torno a la ubicación de las compensaciones deberían estar impulsadas por el potencial para obtener resultados ecológicos equivalentes; sin embargo, al considerar compensaciones más alejadas, existe la necesidad de evaluar el incremento probable de riesgos junto a los beneficios potenciales. Aunque las compensaciones espacialmente flexibles tienen el potencial para proporcionar resultados más rentables y más beneficios colaterales, nuestro estudio de caso mostró la dificultad para demostrar estos beneficios en la práctica y los riesgos potenciales que necesitan considerarse para asegurar una ubicación efectiva de las compensaciones.

Ecological and economic implications of alternative metrics in biodiversity offset markets.

Policy tools are needed that allow reconciliation of human development pressures with conservation priorities. Biodiversity offsetting can be used to compensate for ecological losses caused by development activities. Landowners can choose to undertake conservation actions, including habitat restoration, to generate biodiversity offsets. Consideration of the incentives facing landowners as potential biodiversity offset providers and developers as potential buyers of credits is critical when considering the ecological and economic landscape-scale outcomes of alternative offset metrics. There is an expectation that landowners will always seek to conserve the least profitable land parcels, and, in turn, this determines the spatial location of biodiversity offset credits. We developed an ecological-economic model to compare the ecological and economic outcomes of offsetting for a habitat-based metric and a species-based metric. We were interested in whether these metrics would adequately capture the indirect benefits of offsetting on species not considered under a no-net-loss policy. We simulated a biodiversity offset market for a case study landscape, linking species distribution modeling and an economic model of landowner choice based on economic returns of the alternative land management options (restore, develop, or maintain existing land use). Neither the habitat nor species metric adequately captured the indirect benefits of offsetting on related habitats or species. The underlying species distributions, layered with the agricultural and development rental values of parcels, resulted in very different landscape outcomes depending on the metric chosen. If policy makers are aiming for the metric to act as an indicator to mitigate impacts on a range of closely related habitats and species, then a simple no-net-loss target is not adequate. Furthermore, to achieve the most ecologically beneficial design of offsets policy, an understanding of the economic decision-making processes of the landowners is needed.

Se necesitan herramientas políticas que permitan la reconciliación entre las presiones del desarrollo humano y las prioridades de conservación. La compensación de biodiversidad puede usarse para reponer las pérdidas ecológicas causadas por las actividades de desarrollo. Los terratenientes pueden elegir realizar acciones de conservación, incluyendo la restauración del hábitat, para generar dichas compensaciones. Es importante considerar los incentivos para los terratenientes como proveedores potenciales de compensaciones de biodiversidad y para los desarrolladores como compradores potenciales de créditos cuando se contemplan los resultados ecológicos y económicos a escala de paisaje de estas medidas alternativas de compensación. Existe la expectativa de que los terratenientes siempre buscarán conservar los lotes menos rentables y, por lo tanto, esto determina la ubicación espacial de los créditos por compensación de biodiversidad. Desarrollamos un modelo para comparar los resultados ecológicos y económicos de la compensación en una medida basada en el hábitat y una basada en la especie. Nos interesaba saber si estas medidas indicarían adecuadamente los beneficios indirectos de la compensación para las especies no consideradas bajo una política de pérdida neta cero. Simulamos un mercado voluntario de biodiversidad para un estudio de casode un paisaje, el cual vinculó el modelado de la distribución de especies con el modelo económico de las elecciones de los terratenientes basadas en las ganancias económicas de las opciones alternativas de manejo de suelo (restaurar, desarrollar o mantener el uso de suelo existente). Ninguna de las dos medidas indicó adecuadamente los beneficios indirectos de la compensación para las especies o hábitats relacionados. La distribución subyacente de especies, en conjunto con los valores de renta agrícolas y de desarrollo de los lotes, derivó en resultados muy diferentes de paisaje según la medida seleccionada. Cuando los formuladores de políticas buscan que la medida actúe como un indicador para mitigar impactos en una gama de especies y hábitats relacionados cercanamente, no es adecuado un objetivo simple de pérdida neta cero. Además, para lograr el diseño con el mayor beneficio ecológico, se requiere comprender los procesos de decisión de los terratenientes.

Ecological equivalence assessment: The potential of genetic tools, remote sensing and metapopulation models to better apply the mitigation hierarchy.

Within the framework of the mitigation hierarchy, biodiversity offsetting is the main tool promoted to reach No Net Loss. One of the determining factors of offsetting success is the evaluation of ecological equivalence. Various equivalence assessment methods (EAMs) have been developed to provide a framework to evaluate the balance between expected biodiversity losses and gains. In the context of achieving No Net Loss, EAMs must address challenges of Operationality, Currency, Uncertainty, Spatial scale and Time frame. In this study, we investigated the way the most widely used EAMs address these challenges, positing that certain tools from ecological science could limit the trade-offs between these challenges and improve the ecological assessment process. To this end, we analysed the risks and benefits associated with the inclusion of genetic tools (landscape genetics and eDNA), remote sensing and metapopulation models in selected EAMs. Our results revealed trade-offs between these five challenges, in particular between Operationality and Currency. The EAMs varied strongly in these two aspects, depending on the general assessment approach and the biodiversity component they focus on. To a lesser degree, Time frame and Spatial scale also differed between the methods. We identified that the integration of the different tools differs among them, being easier for remote sensing and metapopulation models than for the genetic tools. Nevertheless, the integration resulted in benefits compared to the current use of the methods - benefits that included improving the objectivation of the assessment and the automatization potential. The tools also show potential for automatization, which could have major benefits for operationality. In terms of risks, the integration of these tools increases the technical complexity of the methods, requiring new skills, and would change the overall approach of the ecological assessment.

Metrics for environmental compensation: A comparative analysis of Swedish municipalities.

Environmental compensation (EC) aims at addressing environmental losses due to development projects and involves a need to compare development losses with compensation gains using relevant metrics. A conceptual procedure for computing no net loss is formulated and used as a point of departure for a comparative analysis of metrics used by five Swedish municipalities as a part of their EC implementation in the spatial planning context of detailed development plans. While Swedish law does not require EC in this context, these municipalities have still decided to introduce EC requirements for development projects that occur on municipality-owned land and to promote voluntary EC among private actors in development projects on private land. There is substantial variation across the municipalities studied with respect to both metrics and attributes subject to measurement, but there are also similarities: The attributes considered when assessing the need for EC in conjunction with development are not only about nature per se, but also about recreational opportunities and other types ecosystem services; semi-quantitative metrics such as scores are common while quantitative or monetary metrics are rare; and metrics are rarely applied to assess compensatory gains, focusing instead on losses from development. Streamlining across municipalities might be warranted for increasing predictability and transparency for developers and citizens, but it also introduces considerable challenges such as a need for developing consistent guidelines for semi-quantitative metrics, and to handle substitutability issues if metrics are not only applied on individual attributes but also on groups of attributes. The broad scope of attributes used by the municipalities is in line with an international tendency to broaden EC to include not only biodiversity aspects but also ecosystem services. Moreover, the EC systems applied by the municipalities are of particular importance for highlighting the crucial role of environmental management for maintaining and enhancing biodiversity and ecosystem services not only in areas having formal protection status but also in the everyday landscape. The municipalities' experience and strengths and weaknesses associated with their EC systems are therefore relevant also in an international perspective.

Exploring the practical implementation of marine biodiversity offsetting in Australia.

Biodiversity offsetting with associated aims of no net loss of biodiversity (NNL) is an approach used to align economic development with conservation. Biodiversity offsetting may be more challenging in marine environments, with recent evidence suggesting that the current application of the approach in Australian marine environments rarely follows 'best practice' and is unlikely to be meeting stated policy aims. To understand how and why this deviation from best practice is taking place in marine systems, we analysed current practice in Australia through in-depth semi-structured interviews with 31 participants with professional experience in the development and implementation of associated policy. Thematic analysis of results indicated that, despite commitment to best practice in principle, practitioners recognised that operationalisation of marine biodiversity offsetting was inconsistent and unlikely to be meeting stated goals such as NNL. Participants described the central barrier to the adoption of best practice as the technical complexity of assessing and quantifying biodiversity losses and gains, and uncertainty in restoration in marine contexts. With offsetting described as an integral part of development consent for marine economic development, both these barriers and their navigation presents threats to users setting off a chain of accepted activity leading away from best practice. These threats were perceived to arise from low governmental capacity or prioritisation for environmental management, institutional needs for a social licence to operate, and overarching demands for economic growth. We conclude that marine biodiversity offsetting has come to be ambiguous in its practical definition, with a range of conflicting factors influencing its use and preventing the standardisation required to meet rigorous interpretations of best practice necessary to ensure biodiversity protection and NNL.

Precision, Applicability, and Economic Implications: A Comparison of Alternative Biodiversity Offset Indexes.

The rates of ecosystem degradation and biodiversity loss are alarming and current conservation efforts are not sufficient to stop them. The need for new tools is urgent. One approach is biodiversity offsetting: a developer causing habitat degradation provides an improvement in biodiversity so that the lost ecological value is compensated for. Accurate and ecologically meaningful measurement of losses and estimation of gains are essential in reaching the no net loss goal or any other desired outcome of biodiversity offsetting. The chosen calculation method strongly influences biodiversity outcomes. We compare a multiplicative method, which is based on a habitat condition index developed for measuring the state of ecosystems in Finland to two alternative approaches for building a calculation method: an additive function and a simpler matrix tool. We examine the different logic of each method by comparing the resulting trade ratios and examine the costs of offsetting for developers, which allows us to compare the cost-effectiveness of different types of offsets. The results show that the outcomes of the calculation methods differ in many aspects. The matrix approach is not able to consider small changes in the ecological state. The additive method gives always higher biodiversity values compared to the multiplicative method. The multiplicative method tends to require larger trade ratios than the additive method when trade ratios are larger than one. Using scoring intervals instead of using continuous components may increase the difference between the methods. In addition, the calculation methods have differences in dealing with the issue of substitutability.

When is an Offset Not an Offset? A Framework of Necessary Conditions for Biodiversity Offsets.

Biodiversity offsets have become a widely accepted means of attempting to compensate for biodiversity loss from development, and are applied in planning and decision-making processes at many levels. Yet their use is contentious, and numerous problems with both the concept and the practice have been identified in the literature. Our starting point is the understanding that offsets are a kind of biodiversity compensation measure through which the goal of no net loss (or net gain) of biodiversity can be at least theoretically achieved. Based on a typology of compensation measures distinguishing between habitat protection, improvement (including restoration, habitat creation and improved management practices) and other compensation, we review the literature to develop a framework of conditions that must be met if habitat protection and improvement initiatives can be truly considered offsets and not merely a lesser form of compensation. It is important that such conceptual clarity is reflected in offset policy and guidance, if offsets are to be appropriately applied and to have any chance of fully compensating for biodiversity loss. Our framework can be used to support the review and ongoing development of biodiversity offset policy and guidance, with the aim of improving clarity, rigour and therefore the chances that good biodiversity outcomes can be achieved.

Environmental mitigation hierarchy and biodiversity offsets revisited through habitat connectivity modelling.

Biodiversity loss is accelerating because of unceasing human activity and land clearing for development projects (urbanisation, transport infrastructure, mining and quarrying …). Environmental policy-makers and managers in different countries worldwide have proposed the mitigation hierarchy to ensure the goal of "no net loss (NNL) of biodiversity" and have included this principle in environmental impact assessment processes. However, spatial configuration is hardly ever taken into account in the mitigation hierarchy even though it would greatly benefit from recent developments in habitat connectivity modelling incorporating landscape graphs. Meanwhile, national, European and international commitments have been made to maintain and restore the connectivity of natural habitats to face habitat loss and fragmentation. Our objective is to revisit the mitigation hierarchy and to suggest a methodological framework for evaluating the environmental impact of development projects, which includes a landscape connectivity perspective. We advocate the use of the landscape connectivity metric equivalent connectivity (EC), which is based on the original concept of "amount of reachable habitat". We also refine the three main levels of the mitigation hierarchy (impact avoidance, reduction and offset) by integrating a landscape connectivity aspect. We applied this landscape connectivity framework to a simple, virtual habitat network composed of 14 patches of varying sizes. The mitigation hierarchy was addressed through graph theory and EC and several scenarios of impact avoidance, reduction and compensation were tested. We present the benefits of a habitat connectivity framework for the mitigation hierarchy, provide practical recommendations to implement this framework and show its use in real case studies that had previously been restricted to one or two steps of the mitigation hierarchy. We insist on the benefits of a habitat connectivity framework for the mitigation hierarchy and for ecological equivalence assessment. In particular, we demonstrate why it is risky to use a standard offset ratio (the ratio between the amount of area negatively impacted and the compensation area) without performing a connectivity analysis that includes the landscape surrounding the zone impacted by the project. We also discuss the limitations of the framework and suggest potential improvements. Lastly, we raise concerns about the need to rethink the strategy for biodiversity protection. Given that wild areas and semi-natural habitats are becoming scarcer, in particular in industrialised countries, we are convinced that the real challenge is to quickly reconsider the current vision of "developing first, then assessing the ecological damage", and instead urgently adopt an upstream protection strategy that would identify and protect the land that must not be lost if we wish to maintain viable species populations and ecological corridors allowing them the mobility necessary to their survival.

A Global Mitigation Hierarchy for Nature Conservation.

Efforts to conserve biodiversity comprise a patchwork of international goals, national-level plans, and local interventions that, overall, are failing. We discuss the potential utility of applying the mitigation hierarchy, widely used during economic development activities, to all negative human impacts on biodiversity. Evaluating all biodiversity losses and gains through the mitigation hierarchy could help prioritize consideration of conservation goals and drive the empirical evaluation of conservation investments through the explicit consideration of counterfactual trends and ecosystem dynamics across scales. We explore the challenges in using this framework to achieve global conservation goals, including operationalization and monitoring and compliance, and we discuss solutions and research priorities. The mitigation hierarchy's conceptual power and ability to clarify thinking could provide the step change needed to integrate the multiple elements of conservation goals and interventions in order to achieve successful biodiversity outcomes.

Accounting for no net loss: A critical assessment of biodiversity offsetting metrics and methods.

Biodiversity offset strategies are based on the explicit calculation of both losses and gains necessary to establish ecological equivalence between impact and offset areas. Given the importance of quantifying biodiversity values, various accounting methods and metrics are continuously being developed and tested for this purpose. Considering the wide array of alternatives, selecting an appropriate one for a specific project can be not only challenging, but also crucial; accounting methods can strongly influence the biodiversity outcomes of an offsetting strategy, and if not well-suited to the context and values being offset, a no net loss outcome might not be delivered. To date there has been no systematic review or comparative classification of the available biodiversity accounting alternatives that aim at facilitating metric selection, and no tools that guide decision-makers throughout such a complex process. We fill this gap by developing a set of analyses to support (i) identifying the spectrum of available alternatives, (ii) understanding the characteristics of each and, ultimately (iii) making the most sensible and sound decision about which one to implement. The metric menu, scoring matrix, and decision tree developed can be used by biodiversity offsetting practitioners to help select an existing metric, and thus achieve successful outcomes that advance the goal of no net loss of biodiversity.

Cost shifting and other perverse incentives in biodiversity offsetting in India.

Biodiversity offsetting aims to compensate for development-induced biodiversity loss through commensurate conservation gains and is gaining traction among governments and businesses. However, cost shifting (i.e., diversion of offset funds to other conservation programs) and other perverse incentives can undermine the effectiveness of biodiversity offsetting. Additionality-the requirement that biodiversity offsets result in conservation outcomes that would not have been achieved otherwise-is fundamental to biodiversity offsetting. Cost shifting and violation of additionality can go hand in hand. India's national offsetting program is a case in point. Recent legislation allows the diversion of offset funds to meet the country's preexisting commitments under the United Nations Framework Convention on Climate Change (UNFCCC) and United Nations Convention on Biological Diversity (CBD). With such diversions, no additional conservation takes place and development impacts remain uncompensated. Temporary additionality cannot be conceded in light of paucity of funds for preexisting commitments unless there is open acknowledgement that fulfillment of such commitments is contingent on offset funds. Two other examples of perverse incentives related to offsetting in India are the touting of inherently neutral offsetting outcomes as conservation gains, a tactic that breeds false complacency and results in reduced incentive for additional conservation efforts, and the clearing of native vegetation for commercial plantations in the name of compensatory afforestation, a practice that leads to biodiversity decline. The risks accompanying cost shifting and other perverse incentives, if not preempted and addressed, will result in net loss of forest cover in India. We recommend accurate baselines, transparent accounting, and open reporting of offset outcomes to ensure biodiversity offsetting achieves adequate and additional compensation for impacts of development.

Ecological Equivalence Assessment Methods: What Trade-Offs between Operationality, Scientific Basis and Comprehensiveness?

In many countries, biodiversity compensation is required to counterbalance negative impacts of development projects on biodiversity by carrying out ecological measures, called offset when the goal is to reach "no net loss" of biodiversity. One main issue is to ensure that offset gains are equivalent to impact-related losses. Ecological equivalence is assessed with ecological equivalence assessment methods taking into account a range of key considerations that we summarized as ecological, spatial, temporal, and uncertainty. When equivalence assessment methods take into account all considerations, we call them "comprehensive". Equivalence assessment methods should also aim to be science-based and operational, which is challenging. Many equivalence assessment methods have been developed worldwide but none is fully satisfying. In the present study, we examine 13 equivalence assessment methods in order to identify (i) their general structure and (ii) the synergies and trade-offs between equivalence assessment methods characteristics related to operationality, scientific-basis and comprehensiveness (called "challenges" in his paper). We evaluate each equivalence assessment methods on the basis of 12 criteria describing the level of achievement of each challenge. We observe that all equivalence assessment methods share a general structure, with possible improvements in the choice of target biodiversity, the indicators used, the integration of landscape context and the multipliers reflecting time lags and uncertainties. We show that no equivalence assessment methods combines all challenges perfectly. There are trade-offs between and within the challenges: operationality tends to be favored while scientific basis are integrated heterogeneously in equivalence assessment methods development. One way of improving the challenges combination would be the use of offset dedicated data-bases providing scientific feedbacks on previous offset measures.

The inclusion of biodiversity in environmental impact assessment: Policy-related progress limited by gaps and semantic confusion.

Natural habitat loss and fragmentation, as a result of development projects, are major causes of biodiversity erosion. Environmental impact assessment (EIA) is the most commonly used site-specific planning tool that takes into account the effects of development projects on biodiversity by integrating potential impacts into the mitigation hierarchy of avoidance, reduction, and offset measures. However, the extent to which EIA fully address the identification of impacts and conservation stakes associated with biodiversity loss has been criticized in recent work. In this paper we examine the extent to which biodiversity criteria have been integrated into 42 EIA from 2006 to 2016 for small development projects in the Montpellier Metropolitan territory in southern France. This study system allowed us to question how EIA integrates biodiversity impacts on a scale relevant to land-use planning. We examine how biodiversity inclusion has changed over time in relation to new policy for EIA and how the mitigation hierarchy is implemented in practice and in comparison with national guidelines. We demonstrate that the inclusion of biodiversity features into EIA has increased significantly in relation to policy change. Several weaknesses nevertheless persist, including the continued absence of substitution solution assessment, a correct analysis of cumulative impacts, the evaluation of impacts on common species, the inclusion of an ecological network scale, and the lack of monitoring and evaluation measures. We also show that measures for mitigation hierarchy are primarily associated with the reduction of impacts rather than their avoidance, and avoidance and offset measures are often misleadingly proposed in EIA. There is in fact marked semantic confusion between avoidance, reduction and offset measures that may impair stakeholders' understanding. All in all, reconsideration of stakeholders routine practices associated with a more strategic approach towards impact anticipation and avoidance at a land-use planning scale is now necessary for the mitigation hierarchy to become a clear and practical hierarchy for "no net loss" objectives based on conservation priorities.

How humans drive speciation as well as extinction.

A central topic for conservation science is evaluating how human activities influence global species diversity. Humanity exacerbates extinction rates. But by what mechanisms does humanity drive the emergence of new species? We review human-mediated speciation, compare speciation and known extinctions, and discuss the challenges of using net species diversity as a conservation objective. Humans drive rapid evolution through relocation, domestication, hunting and novel ecosystem creation-and emerging technologies could eventually provide additional mechanisms. The number of species relocated, domesticated and hunted during the Holocene is of comparable magnitude to the number of observed extinctions. While instances of human-mediated speciation are known, the overall effect these mechanisms have upon speciation rates has not yet been quantified. We also explore the importance of anthropogenic influence upon divergence in microorganisms. Even if human activities resulted in no net loss of species diversity by balancing speciation and extinction rates, this would probably be deemed unacceptable. We discuss why, based upon 'no net loss' conservation literature-considering phylogenetic diversity and other metrics, risk aversion, taboo trade-offs and spatial heterogeneity. We conclude that evaluating speciation alongside extinction could result in more nuanced understanding of biosphere trends, clarifying what it is we actually value about biodiversity.

FORUM: Indirect leakage leads to a failure of avoided loss biodiversity offsetting.

Biodiversity offsetting has quickly gained political support all around the world. Avoided loss (averted risk) offsetting means compensation for ecological damage via averted loss of anticipated impacts through the removal of threatening processes in compensation areas.Leakage means the phenomenon of environmentally damaging activity relocating elsewhere after being stopped locally by avoided loss offsetting. Indirect leakage means that locally avoided losses displace to other administrative areas or spread around diffusely via market effects. Synthesis and applications. Indirect leakage can lead to high net biodiversity loss. It is difficult to measure or prevent, raising doubts about the value of avoided loss offsetting. Market demand for commodities is on the rise, following increasing human population size and per capita consumption, implying that indirect leakage will be a rule rather than an exception. Leakage should be accounted for when determining offset multipliers (ratios) even if multipliers become extremely high.

A method for calculating minimum biodiversity offset multipliers accounting for time discounting, additionality and permanence.

Biodiversity offsetting, which means compensation for ecological and environmental damage caused by development activity, has recently been gaining strong political support around the world. One common criticism levelled at offsets is that they exchange certain and almost immediate losses for uncertain future gains. In the case of restoration offsets, gains may be realized after a time delay of decades, and with considerable uncertainty. Here we focus on offset multipliers, which are ratios between damaged and compensated amounts (areas) of biodiversity. Multipliers have the attraction of being an easily understandable way of deciding the amount of offsetting needed. On the other hand, exact values of multipliers are very difficult to compute in practice if at all possible. We introduce a mathematical method for deriving minimum levels for offset multipliers under the assumption that offsetting gains must compensate for the losses (no net loss offsetting). We calculate absolute minimum multipliers that arise from time discounting and delayed emergence of offsetting gains for a one-dimensional measure of biodiversity. Despite the highly simplified model, we show that even the absolute minimum multipliers may easily be quite large, in the order of dozens, and theoretically arbitrarily large, contradicting the relatively low multipliers found in literature and in practice. While our results inform policy makers about realistic minimal offsetting requirements, they also challenge many current policies and show the importance of rigorous models for computing (minimum) offset multipliers. The strength of the presented method is that it requires minimal underlying information. We include a supplementary spreadsheet tool for calculating multipliers to facilitate application.