A Global Mitigation Hierarchy for Nature Conservation

Sentiment and attitudes toward offsetting and the biodiversity market in online media articles

Biodiversity offsetting, a conservation approach to offset loss of habitat and ecosystem services, has been widely accepted and implemented in different legislative frameworks around the globe. I assigned sentiment scores (from -3 [very negative] to +3 [very positive]) to online news articles to examine public sentiment toward offsetting. I identified 86 pertinent articles published from 2013 to 2023 by web scraping online media outlets through keywords. I examined article content based on topics commonly associated in scientific literature with offsetting, such as risks or financial aspects. Most articles were from Australia (44%), 16% were from the United Kingdom, and 5% were from Colombia and Madagascar. Three distinct groups covered finances (n = 47), species, and social impacts of offsetting (n = 23) and offsetting frameworks (n = 16). Articles covering monetary and finance aspects had a lower predicted sentiment score (-0.72, 95% CI -0.98 to -0.47) than articles that covered new, alternative offsetting forms (-0.15, 95% CI -0.46 to 0.17), such as mitigation banking and credits. In articles focused on charismatic species and loss of livelihood, offsetting risk and social issues were associated with low sentiment scores (<-0.85). Sentiment scores were high for articles on offsetting at a multicountry or global scale (0.47, 95% CI -0.06 to 0.99), and scores were the lowest in Australia (-1.03, 95% CI -1.36 to -0.70). Public sentiment based on media articles was generally negative toward offsetting, and many of the ecological and methodological issues and risks were reflected in the articles, but mitigation measures as a prerequisite to offsetting were mentioned in only 18% of all articles. With the seemingly high public interest in conservation and hence offsetting, it will be imperative to expand the current breadth of information about offsetting that is being communicated or made available to the public.

Threat of mining to African great apes

The rapid growth of clean energy technologies is driving a rising demand for critical minerals. In 2022 at the 15th Conference of the Parties to the Convention on Biological Diversity (COP15), seven major economies formed an alliance to enhance the sustainability of mining these essential decarbonization minerals. However, there is a scarcity of studies assessing the threat of mining to global biodiversity. By integrating a global mining dataset with great ape density distribution, we estimated the number of African great apes that spatially coincided with industrial mining projects. We show that up to one-third of Africa's great ape population faces mining-related risks. In West Africa in particular, numerous mining areas overlap with fragmented ape habitats, often in high-density ape regions. For 97% of mining areas, no ape survey data are available, underscoring the importance of increased accessibility to environmental data within the mining sector to facilitate research into the complex interactions between mining, climate, biodiversity, and sustainability.

Toward solving the global green-green dilemma between wind energy production and bat conservation

Wind energy production is growing rapidly worldwide in an effort to reduce greenhouse gas emissions. However, wind energy production is not environmentally neutral. Negative impacts on volant animals, such as bats, include fatalities at turbines and habitat loss due to land-use change and displacement. Siting turbines away from ecologically sensitive areas and implementing measures to reduce fatalities are critical to protecting bat populations. Restricting turbine operations during periods of high bat activity is the most effective form of mitigation currently available to reduce fatalities. Compensating for habitat loss and offsetting mortality are not often practiced, because meaningful offsets are lacking. Legal frameworks to prevent or mitigate the negative impacts of wind energy on bats are absent in most countries, especially in emerging markets. Therefore, governments and lending institutions are key in reconciling wind energy production with biodiversity goals by requiring sufficient environmental standards for wind energy projects.

Potential impacts of proposed lithium extraction on biodiversity and conservation in the contiguous United States

To address climate change, the United States is offering consumers incentives to purchase electric vehicles containing domestically derived lithium batteries. New extraction facilities required to supply this lithium may have environmental impacts, including impacts on biodiversity. To reveal potential impacts, we mapped 72 proposed lithium extraction sites across the contiguous United States and overlaid these with data for species occurrences, conservation value, habitat, and land management designations. We found that potential impacts vary by site. The abundance of lithium resources in the United States, combined with large differences in potential impacts among sites, suggests that decision-makers may be able to guide lithium extraction to the least impactful sites first. To aid this process, we recommend field-based reconnaissance of proposed lithium extraction sites, and a cumulative analysis of potential impacts on biodiversity in order to contextualize this activity within the larger scope of land use and climate change.

Threats to conservation from national security interests

There is a growing trend of nation states invoking national security and emergency declarations to build state-sponsored infrastructure projects for border defense, energy production, and transportation. Established laws, regulations, and agreements for the protection of nature and cultural heritage within and between countries are becoming secondary to national security, compromising the function of protected areas, such as national parks, wilderness areas, and biosphere reserves that safeguard biodiversity, climate, and human health. We considered cases where decades-long multinational cross-border endangered species recovery programs have been jeopardized by waivers of environmental protection laws to facilitate rapid construction of border barriers that impede the movement and migration of animals, such as at the US-Mexico and Poland-Belarus borders. Renewable energy megaprojects, such as the Pinacate solar plant in Mexico, coupled with power transmission lines and road networks likewise cast a large footprint on the land and are being carried out with minimal to no environmental compliance under the guise of national security. National sovereignty likewise has been used as justification for bypassing laws to proceed with similar projects, such as Mexico's Dos Bocas refinery and Poland's Vistula Spit canal. Emphasis on security is also apparent in increasing military expenditure by the world's largest economies, which has created a mismatch with improvement in environmental policy stringency. Decisions to prioritize security can undermine democratic principles and environmental review protocols, trivialize humanity's dependence on functioning ecosystems, and contradict the United Nation's resolution on the human right to a healthy environment. Framing infrastructure projects as matters of national security also foments civil and political unrest by the labeling and casting of dissenters, including conservation scientists and environmental defenders, as antinational. World leaders must refrain from misusing extraordinary powers, adhere to laws and international agreements, and consult experts and local people before taking unilateral action on projects that affect ecological and human communities.

The Present and Future of Insect Biodiversity Conservation in the Neotropics: Policy Gaps and Recommendations

Emerging evidence suggests that insect populations may be declining at local and global scales, threatening the sustainability of the ecosystem services that insects provide. Insect declines are of particular concern in the Neotropics, which holds several of the world's hotspots of insect endemism and diversity. Conservation policies are one way to prevent and mitigate insect declines, yet these policies are usually biased toward vertebrate species. Here, we outline some key policy instruments for biodiversity conservation in the Neotropics and discuss their potential contribution and shortcomings for insect biodiversity conservation. These include species-specific action policies, protected areas and Indigenous and Community Conserved Areas (ICCAs), sectoral policies, biodiversity offsetting, market-based mechanisms, and the international policy instruments that underpin these efforts. We highlight that although these policies can potentially benefit insect biodiversity indirectly, there are avenues in which we could better incorporate the specific needs of insects into policy to mitigate the declines mentioned above. We propose several areas of improvement. Firstly, evaluating the extinction risk of more Neotropical insects to better target at-risk species with species-specific policies and conserve their habitats within area-based interventions. Secondly, alternative pest control methods and enhanced monitoring of insects in a range of land-based production sectors. Thirdly, incorporating measurable and achievable insect conservation targets into international policies and conventions. Finally, we emphasise the important roles of community engagement and enhanced public awareness in achieving these improvements to insect conservation policies.

Nature-positive goals for an organization's food consumption

Organizations are increasingly committing to biodiversity protection targets with focus on 'nature-positive' outcomes, yet examples of how to feasibly achieve these targets are needed. Here we propose an approach to achieve nature-positive targets with respect to the embodied biodiversity impacts of an organization's food consumption. We quantify these impacts using a comprehensive database of life-cycle environmental impacts from food, and map exploratory strategies to meet defined targets structured according to a mitigation and conservation hierarchy. By considering the varying needs and values across the organization's internal community, we identify a range of targeted approaches towards mitigating impacts, which balance top-down and bottom-up actions to different degrees. Delivering ambitious nature-positive targets within current constraints will be challenging, particularly given the need to mitigate cumulative impacts. Our results evidence that however committed an organization is to being nature positive in its food provision, this is unachievable in the absence of systems change.

Managing the effects of multiple stressors on wildlife populations in their ecosystems: developing a cumulative risk approach

Assessing cumulative effects of human activities on ecosystems is required by many jurisdictions, but current science cannot meet regulatory demands. Regulations define them as effect(s) of one human action combined with other actions. Here we argue for an approach that evaluates the cumulative risk of multiple stressors for protected wildlife populations within their ecosystems. Monitoring effects of each stressor is necessary but not sufficient to estimate how multiple stressors interact to affect wildlife populations. Examining the mechanistic pathways, from cellular to ecological, by which stressors affect individuals can help prioritize stressors and interpret how they interact. Our approach uses health indicators to accumulate the effects of stressors on individuals and to estimate changes in vital rates, driving population status. We advocate using methods well-established in human health and integrating them into ecosystem-based management to protect the health of commercially and culturally important wildlife populations and to protect against risk of extinction for threatened species. Our approach will improve abilities to conserve and manage ecosystems but will also demand significant increases in research and monitoring effort. We advocate for increased investment proportional to the economic scale of human activities in the Anthropocene and their pervasive effects on ecology and biodiversity.

A Meta-analysis on the Effectiveness of Offsetting Strategies to Address Harm to Freshwater Fishes

Offsetting aims to compensate for negative impacts due to authorized anthropogenic impacts associated with development. While anchored into legislation, residual or chronic impacts can occur after offset establishment. Advice and best practice on how to approach these impacts is rare. To address this, we reviewed 30 projects based on a systematic review and meta-analysis in freshwater ecosystems dealing with residual or long-term negative impacts to provide application advice for: habitat creation, habitat restoration, and biological and chemical manipulation. Project information was obtained through Boolean search terms and web-scraping. Habitat creation projects had a pooled effect size of 0.8 and offsetting ratios of 1:5 with high biomass increases of &gt;140% compared to pre-establishment, associated with them. Habitat restoration projects targeted a wide range of species and communities with a pooled effect size of 0.66, offset ratios ranging from 1:1.2 to 1:4.6, and biomass increases generally &gt; 100% compared to pre-restoration. Biological manipulation had the lowest effect size (0.51) with stocking being highly variable both in terms of biomass benefits and project outcomes pointing towards being mostly applicable in cases of direct fish harm not related to habitat aspects. We conclude that (1) all three assessed approaches have a potential application use for offsetting residual or chronic harm with approach-specific caveats. (2) Implementation costs differ across offset methods, with connectivity and side-channel projects having the lowest biomass gain per area costs (3) Time to first benefits required one to two years with time lags needing to be accounted for in the implementation and monitoring process.

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.

A global overview of biodiversity offsetting governance

We analyze the development of biodiversity offsetting governance through a research-weaving approach. Here, we combine information from a systematized review of the literature and a qualitative analysis of the institutional developments in different world regions. Through this triangulation, we synthesize and map the different developmental streams of biodiversity offsetting governance around the globe over the last four decades. We find that there is a global mainstreaming of core principles such as avoidance, no-net-loss, and a mitigation hierarchy, as well as pooling and trading of offsets for unavoidable residual damages. Furthermore, we can observe an ongoing diversification of institutional designs and actors involved. Together this constitutes an emerging regime complex of biodiversity offsetting governance that comes with both a set of shared norms and a growing institutional complexity. While this may imply institutional innovation through diversification and policy experimentation, it also raises questions regarding the effectiveness of offsetting practices.

The minimum land area requiring conservation attention to safeguard biodiversity

Ambitious conservation efforts are needed to stop the global biodiversity crisis. In this study, we estimate the minimum land area to secure important biodiversity areas, ecologically intact areas, and optimal locations for representation of species ranges and ecoregions. We discover that at least 64 million square kilometers (44% of terrestrial area) would require conservation attention (ranging from protected areas to land-use policies) to meet this goal. More than 1.8 billion people live on these lands, so responses that promote autonomy, self-determination, equity, and sustainable management for safeguarding biodiversity are essential. Spatially explicit land-use scenarios suggest that 1.3 million square kilometers of this land is at risk of being converted for intensive human land uses by 2030, which requires immediate attention. However, a sevenfold difference exists between the amount of habitat converted in optimistic and pessimistic land-use scenarios, highlighting an opportunity to avert this crisis. Appropriate targets in the Post-2020 Global Biodiversity Framework to encourage conservation of the identified land would contribute substantially to safeguarding biodiversity.

Identifying management opportunities to combat climate, land, and marine threats across less climate exposed coral reefs

Conserving coral reefs is critical for maintaining marine biodiversity, protecting coastlines, and supporting livelihoods in many coastal communities. Climate change threatens coral reefs globally, but researchers have identified a portfolio of coral reefs (bioclimatic units [BCUs]) that are relatively less exposed to climate impacts and strongly connected to other coral reef systems. These reefs provide a proactive opportunity to secure a long-term future for coral reefs under climate change. To help guide local management efforts, we quantified marine cumulative human impact (CHI) from climate, marine, and land pressures (2013 and from 2008 to 2013) in BCUs and across countries tasked with BCU management. Additionally, we created a management index based on common management measures and policies for each pressure source (climate, marine, and land) to identify a country's intent and commitment to effectively manage these pressures. Twenty-two countries (79%) had increases in CHI from 2008 to 2013. Climate change pressures had the highest proportional contribution to CHI across all reefs and in all but one country (Singapore), but 18 BCUs (35%) and nine countries containing BCUs (32%) had relatively high land and marine impacts. There was a significant positive relationship between climate impact and the climate management index across countries (R² = 0.43, p = 0.02), potentially signifying that countries with greater climate impacts are more committed to managing them. However, this trend was driven by climate management intent in Fiji and Bangladesh. Our results can be used to guide future fine-scale analyses, national policies, and local management decisions, and our management indices reveal areas where management components can be improved. Cost-effectively managing local pressures (e.g., fishing and nutrients) in BCUs is essential for building a climate-ready future that benefits coral reefs and people.

Assessing Conservation and Mitigation Banking Practices and Associated Gains and Losses in the United States

Conservation and mitigation banks allow their proponents to buy credits to offset the negative residual impacts of their development projects with the goal of no net loss (NNL) in the ecosystem function and habitat area. However, little is known about the extent to which these bank transactions achieve NNL. We synthesized and reviewed 12,756 transactions in the United States which were related to meeting area and ecological equivalence (n = 4331) between the approved negative impact and offset. While most of these transactions provided an offset that was equal to or greater than the impacted area, approximately one quarter of the transactions, especially those targeting wetlands, did not meet ecological equivalence between the impact and offset. This missing ecological equivalence was often due to the significantly increasing use of preservation, enhancement, and rehabilitation over creating new ecosystems through establishment and re-establishment. Stream transactions seldom added new ecosystem area through creation but mainly used rehabilitation in order to add offset benefits, in many cases leading to a net loss of area. Our results suggest that best practice guidance on habitat creation as well as the incentivization of habitat creation must increase in the future to avoid net loss through bank transactions and to meet the ever-accelerating global changes in land use and the increased pressure of climate change.

Advancing Global Biodiversity Governance: Recommendations for Strengthening the Post-2020 Global Biodiversity Framework

Abstract

Reversing ecosystem degradation and halting global biodiversity loss due to climate change and other anthropogenic drivers are essential for socioeconomic development and human wellbeing, as well as for advancing global sustainability. The latest initiative in this direction is the ‘Post-2020 Global Biodiversity Framework’, which establishes a blueprint for global coordinated action towards development of national and regional strategies targeting conservation and sustainable utilization of biodiversity. By supporting the notion of ‘ecological civilization’, it emphasises the need for transformative strategies to conserve, monitor and sustainably manage ecosystems by 2030. Arguably the articulation of fit-for-purpose goals and targets is a key precondition for achieving this vision by enhancing cooperation and influencing the development of implementation strategies and regulatory instruments at national and local levels. The present Policy Analysis critically reviews the key features of the draft Post-2020 Global Biodiversity Framework and suggests recommendations to further strengthen it.

Graphical Abstract

Biodiversity conservation is imperative for planetary resilience and human health and wellbeing.

The Post-2020 Global Biodiversity framework aims to guide biodiversity governance towards ‘ecological civilization’.

Transformative approaches targeting climate adaptation and mitigation, circularity, biodiversity renewal and nature-based solutions require better inclusion.

Attainable and widely acceptable indicators for the different targets are necessary to ensure the framework’s effectiveness.

The interface of climate change mitigation, adaptation and biodiversity conservation should be further strengthened in the framework.

Severe conservation risks of roads on apex predators

The global expansion of road networks threatens apex predator conservation and ecosystem functioning. This occurs through wildlife-vehicle collisions, habitat loss and fragmentation, reduced genetic connectivity and increased poaching. We reviewed road impacts on 36 apex predator species and assessed their risk from current roads based on road exposure and species vulnerability. Our findings reveal all apex predators are exposed to road impacts. Eight of the ten species with the highest risk occur in Asia, although other high-risk species are present in the Americas, Africa and Europe. The sloth bear suffers the highest risk of all apex predators, followed by the tiger and dhole. Based on species risk from roads, we propose a widely applicable method to assess the potential impact of future roads on apex predators. We applied this method to proposed road developments in three areas: the Brazilian Amazon, Africa, and Nepal, to locate high-impact road segments. Roughly 500 protected areas will be intersected by these roads, threatening core apex predator habitats. We advocate the need for rigorous road development planning to apply effective mitigation measures as an urgent priority and to avoid construction in wilderness areas and predator strongholds.

Ten facts about land systems for sustainability

Land use is central to addressing sustainability issues, including biodiversity conservation, climate change, food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard truths that have strong, general, empirical support. These facts help to explain the challenges of achieving sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and values of land are socially constructed and contested; 2) land systems exhibit complex behaviors with abrupt, hard-to-predict changes; 3) irreversible changes and path dependence are common features of land systems; 4) some land uses have a small footprint but very large impacts; 5) drivers and impacts of land-use change are globally interconnected and spill over to distant locations; 6) humanity lives on a used planet where all land provides benefits to societies; 7) land-use change usually entails trade-offs between different benefits-"win-wins" are thus rare; 8) land tenure and land-use claims are often unclear, overlapping, and contested; 9) the benefits and burdens from land are unequally distributed; and 10) land users have multiple, sometimes conflicting, ideas of what social and environmental justice entails. The facts have implications for governance, but do not provide fixed answers. Instead they constitute a set of core principles which can guide scientists, policy makers, and practitioners toward meeting sustainability challenges in land use.

Diversity of European habitat types is correlated with geography more than climate and human pressure

Habitat richness, that is, the diversity of ecosystem types, is a complex, spatially explicit aspect of biodiversity, which is affected by bioclimatic, geographic, and anthropogenic variables. The distribution of habitat types is a key component for understanding broad-scale biodiversity and for developing conservation strategies. We used data on the distribution of European Union (EU) habitats to answer the following questions: (i) how do bioclimatic, geographic, and anthropogenic variables affect habitat richness? (ii) Which of those factors is the most important? (iii) How do interactions among these variables influence habitat richness and which combinations produce the strongest interactions? The distribution maps of 222 terrestrial habitat types as defined by the Natura 2000 network were used to calculate habitat richness for the 10 km × 10 km EU grid map. We then investigated how environmental variables affect habitat richness, using generalized linear models, generalized additive models, and boosted regression trees. The main factors associated with habitat richness were geographic variables, with negative relationships observed for both latitude and longitude, and a positive relationship for terrain ruggedness. Bioclimatic variables played a secondary role, with habitat richness increasing slightly with annual mean temperature and overall annual precipitation. We also found an interaction between anthropogenic variables, with the combination of increased landscape fragmentation and increased population density strongly decreasing habitat richness. This is the first attempt to disentangle spatial patterns of habitat richness at the continental scale, as a key tool for protecting biodiversity. The number of European habitats is related to geography more than climate and human pressure, reflecting a major component of biogeographical patterns similar to the drivers observed at the species level. The interaction between anthropogenic variables highlights the need for coordinated, continental-scale management plans for biodiversity conservation.

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.

Defining Pathways towards African Ecological Futures

Africa has experienced unprecedented growth across a range of development indices for decades. However, this growth is often at the expense of Africa’s biodiversity and ecosystems, jeopardizing the livelihoods of millions of people depending on the goods and services provided by nature, with broader consequences for achieving the United Nations Sustainable Development Goals. Encouragingly, Africa can still take a more sustainable path. Here, we synthesize the key learnings from the African Ecological Futures project. We report results from a participatory scenario planning process around four collectively-owned scenarios and narratives for the evolution of Africa’s ecological resource base over the next 50 years. These scenarios provided a lens to review pressures on the natural environment, through the drivers, pressures, state, impacts, and responses (DPSIR) framework. Based on the outcomes from each of these steps, we discuss opportunities to reorient Africa’s development trajectories towards a sustainable path. These opportunities fall under the broad categories of “effective natural resource governance”, “strategic planning capabilities”, “investment safeguards and frameworks”, and “new partnership models”. Underpinning all these opportunities are “data, management information, and decision support frameworks”. This work can help inform collaborative action by a broad set of actors with an interest in ensuring a sustainable ecological future for Africa.

Mitigating the Impacts of Development Corridors on Biodiversity: A Global Review

Development corridors are extensive, often transnational and linear, geographical areas targeted for investment to help achieve sustainable development. They often comprise the creation of hard infrastructure (i.e., physical structures) and soft infrastructure (i.e., policies, plans, and programmes) involving a variety of actors. They are globally widespread, and likely to be a significant driver of habitat loss. Here, we describe the development corridors phenomenon from a biodiversity perspective and identify the elements of best practice in biodiversity impact mitigation. We use these to carry out a review of the peer reviewed literature on corridors to respond to three questions: (i) how impacts on biodiversity and ecosystem services are assessed; (ii) what mitigation measures are discussed to manage these impacts; and (iii) to what extent do these measures approximate to best practice. We found that of 271 publications on development corridors across all continents (except for Antarctica) mentioning biodiversity or ecosystem services, only 100 (37%) assessed impacts on biodiversity and 7 (3%) on ecosystem services. Importantly, only half of these (52, 19% of the total 271 articles) discussed mitigation measures to manage these impacts. These measures focused on avoidance and minimisation and there was scant mention of restoration or ecological compensation illustrating a deficient application of the mitigation hierarchy. We conclude that the academic literature on corridors does not give sufficient consideration to comprehensive mitigation of biodiversity impacts. To change this, impact assessment research needs to acknowledge the complexity of such multi-project and multi-stakeholder initiatives, quantify biodiversity losses due to the full suite of their potential direct, indirect and cumulative impacts, and follow all the steps of the mitigation hierarchy impact framework. We suggest a series of research avenues and policy recommendations to improve impact assessments of corridors towards achieving better biodiversity outcomes.

Highest risk abandoned, lost and discarded fishing gear

Derelict abandoned, lost and discarded fishing gear have profound adverse effects. We assessed gear-specific relative risks from derelict gear to rank-order fishing methods based on: derelict gear production rates, gear quantity indicators of catch weight and fishing grounds area, and adverse consequences from derelict gear. The latter accounted for ghost fishing, transfer of microplastics and toxins into food webs, spread of invasive alien species and harmful microalgae, habitat degradation, obstruction of navigation and in-use fishing gear, and coastal socioeconomic impacts. Globally, mitigating highest risk derelict gear from gillnet, tuna purse seine with fish aggregating devices, and bottom trawl fisheries achieves maximum conservation gains. Locally, adopting controls following a sequential mitigation hierarchy and implementing effective monitoring, surveillance and enforcement systems are needed to curb derelict gear from these most problematic fisheries. Primary and synthesis research are priorities to improve future risk assessments, produce the first robust estimate of global derelict gear quantity, and assess the performance of initiatives to manage derelict gear. Findings from this first quantitative estimate of gear-specific relative risks from derelict gear guide the allocation of resources to achieve the largest improvements from mitigating adverse effects of derelict gear from the world's 4.6 million fishing vessels.

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.

Three ways to deliver a net positive impact with biodiversity offsets

Biodiversity offsetting is the practice of using conservation actions, such as habitat restoration, management, or protection, to compensate for ecological losses caused by development activity, including construction projects. The typical goal of offsetting is no net loss (NNL), which means that all ecological losses are compensated for by commensurate offset gains. We focused on a conceptual and methodological exploration of net positive impact (NPI), an ambitious goal that implies commitment beyond NNL and that has recently received increasing attention from big business and environmental nongovernmental organizations. We identified 3 main ways NPI could be delivered: use of an additional NPI multiplier; use of slowly developing permanent offsets to deliver additional gains after NNL has first been reached during a shorter offset evaluation time interval; and the combination of permanent offsets with partially temporary losses. An important and novel variant of the last mechanism is the use of an alternate mitigation hierarchy so that gains from the traditional third step of the mitigation hierarchy (i.e., onsite rehabilitation) are no longer be counted toward reduced offset requirements. The outcome from these 3 factors is that for the same ecological damage, larger offsets will be required than previously, thereby improving offset success. As a corollary, we show that offsets are NNL only at 1 ephemeral point in time, before which they are net negative and after which they become either NPI or net negative impact, depending on whether permanent offsets are combined with partially temporary losses or if temporary offset gains are combined with partially permanent losses. To achieve NPI, offsets must be made permanent, and they must achieve NNL during an agreed-upon offset evaluation period. An additional NPI-multiplier and use of the modified mitigation hierarchy will deliver additional NPI gains. Achieving NPI is fully conditional on prior achievement of NNL, and NNL offsets have been frequently observed to fail due to inadequate policy requirements, poor planning, or incomplete implementation. Nevertheless, achieving NPI becomes straightforward if NNL can be credibly reached first.

Ten bridges on the road to recovering Canada’s endangered species

Wildlife is declining around the world. Many developed nations have enacted legislation on endangered species protection and provide funding for wildlife recovery. Protecting endangered species is also supported by the public and judiciary. Yet, despite what appear as enabling conditions, wild species continue to decline. Our paper explores pathways to endangered species recovery by analyzing the barriers that have been identified in Canada, the United States, and Australia. We summarize these findings based on Canada’s Species at Risk Conservation Cycle (assessment, protection, recovery planning, implementation, and monitoring and evaluation) and then identify 10 “bridges” that could help overcome these barriers and bend our current trajectory of wildlife loss to recovery. These bridges include ecosystem approaches to recovery, building capacity for community co-governance, linking wildlife recovery to ecosystem services, and improving our storytelling about the loss and recovery of wildlife. The focus of our conclusions is the Canadian setting, but our findings can be applied in other national and subnational settings to reverse the decline of wildlife and halt extinction.

A framework for evaluating biodiversity mitigation metrics

Biodiversity mitigation is a cornerstone of applied conservation. Mitigation encompasses a suite of practices, ranging from planned avoidance of impacts to creation of new natural habitats. Accurate and appropriate metrics quantifying impacts to natural systems and the effectiveness of restoration are necessary to measure the success of different mitigation strategies. Because effective mitigation requires adequate metrics, we developed a Biodiversity Metrics Framework to assist practitioners and policy makers in assessing biodiversity mitigation metrics. Based on Noss' Hierarchy of Biodiversity, the Scorecard highlights the mismatch between scientifically defined best practices and metrics required by policy. The Framework may serve a vital role in standardizing and validating mitigation projects into the future.

Renewable energy development threatens many globally important biodiversity areas

Transitioning from fossil fuels to renewable energy is fundamental for halting anthropogenic climate change. However, renewable energy facilities can be land-use intensive and impact conservation areas, and little attention has been given to whether the aggregated effect of energy transitions poses a substantial threat to global biodiversity. Here, we assess the extent of current and likely future renewable energy infrastructure associated with onshore wind, hydropower and solar photovoltaic generation, within three important conservation areas: protected areas (PAs), Key Biodiversity Areas (KBAs) and Earth's remaining wilderness. We identified 2,206 fully operational renewable energy facilities within the boundaries of these conservation areas, with another 922 facilities under development. Combined, these facilities span and are degrading 886 PAs, 749 KBAs and 40 distinct wilderness areas. Two trends are particularly concerning. First, while the majority of historical overlap occurs in Western Europe, the renewable electricity facilities under development increasingly overlap with conservation areas in Southeast Asia, a globally important region for biodiversity. Second, this next wave of renewable energy infrastructure represents a ~30% increase in the number of PAs and KBAs impacted and could increase the number of compromised wilderness areas by ~60%. If the world continues to rapidly transition towards renewable energy these areas will face increasing pressure to allow infrastructure expansion. Coordinated planning of renewable energy expansion and biodiversity conservation is essential to avoid conflicts that compromise their respective objectives.

Local conditions and policy design determine whether ecological compensation can achieve No Net Loss goals

Many nations use ecological compensation policies to address negative impacts of development projects and achieve No Net Loss (NNL) of biodiversity and ecosystem services. Yet, failures are widely reported. We use spatial simulation models to quantify potential net impacts of alternative compensation policies on biodiversity (indicated by native vegetation) and two ecosystem services (carbon storage, sediment retention) across four case studies (in Australia, Brazil, Indonesia, Mozambique). No policy achieves NNL of biodiversity in any case study. Two factors limit their potential success: the land available for compensation (existing vegetation to protect or cleared land to restore), and expected counterfactual biodiversity losses (unregulated vegetation clearing). Compensation also fails to slow regional biodiversity declines because policies regulate only a subset of sectors, and expanding policy scope requires more land than is available for compensation activities. Avoidance of impacts remains essential in achieving NNL goals, particularly once opportunities for compensation are exhausted.

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.

Reduced ecological resilience jeopardizes zero loss of biodiversity using the mitigation hierarchy

One proposal for the Convention on Biological Diversity's post-2020 strategic plan is 'zero loss' of natural habitats. However, the feasibility of zero loss was questioned during the Trondheim Conference for Biodiversity, and it was suggested that biodiversity losses are instead balanced by compensatory efforts (that is, 'no net loss'). The focus on net outcomes is echoed by separate calls for a global mitigation hierarchy to deliver no net biodiversity loss and accommodate both conservation and development goals. Here we show that 'no net loss' is not the same as 'zero loss'. We use a delayed differential model of nonlinear habitat dynamics to demonstrate how applying the mitigation hierarchy for net biodiversity outcomes will lead to biodiversity declines by midcentury. Delayed compensation of human impacts reduces ecological resilience and causes prolonged biodiversity losses. These effects are greatest when impacts are large and compensation delays are long. Our results support the use of fixed targets, rather than net outcomes, as part of the post-2020 biodiversity framework.

A global assessment of the drivers of threatened terrestrial species richness

High numbers of threatened species might be expected to occur where overall species richness is also high; however, this explains only a proportion of the global variation in threatened species richness. Understanding why many areas have more or fewer threatened species than would be expected given their species richness, and whether that is consistent across taxa, is essential for identifying global conservation priorities. Here, we show that, after controlling for species richness, environmental factors, such as temperature and insularity, are typically more important than human impacts for explaining spatial variation in global threatened species richness. Human impacts, nevertheless, have an important role, with relationships varying between vertebrate groups and zoogeographic regions. Understanding this variation provides a framework for establishing global conservation priorities, identifying those regions where species are inherently more vulnerable to the effects of threatening human processes, and forecasting how threatened species might be distributed in a changing world.

Bending the Curve of Global Freshwater Biodiversity Loss: An Emergency Recovery Plan

Despite their limited spatial extent, freshwater ecosystems host remarkable biodiversity, including one-third of all vertebrate species. This biodiversity is declining dramatically: Globally, wetlands are vanishing three times faster than forests, and freshwater vertebrate populations have fallen more than twice as steeply as terrestrial or marine populations. Threats to freshwater biodiversity are well documented but coordinated action to reverse the decline is lacking. We present an Emergency Recovery Plan to bend the curve of freshwater biodiversity loss. Priority actions include accelerating implementation of environmental flows; improving water quality; protecting and restoring critical habitats; managing the exploitation of freshwater ecosystem resources, especially species and riverine aggregates; preventing and controlling nonnative species invasions; and safeguarding and restoring river connectivity. We recommend adjustments to targets and indicators for the Convention on Biological Diversity and the Sustainable Development Goals and roles for national and international state and nonstate actors.

Improving averted loss estimates for better biodiversity outcomes from offset exchanges

Biodiversity offsetting aims to achieve at least no net loss of biodiversity by fully compensating for residual development-induced biodiversity losses after the mitigation hierarchy (avoid, minimize, remediate) has been applied. Actions used to generate offsets can include securing site protection, or maintaining or enhancing the condition of targeted biodiversity at an offset site. Protection and maintenance actions aim to prevent future biodiversity loss, so such offsets are referred to as averted loss offsets. However, the benefits of such approaches can be highly uncertain and opaque, because assumptions about the change in likelihood of loss as a result of the offset action are often implicit. As a result, the gain generated by averting losses can be intentionally or inadvertently overestimated, leading to offset outcomes that are insufficient for achieving no net loss of biodiversity. We present a method and decision tree to guide consistent and credible estimation of the likelihood of biodiversity loss for a proposed offset site with and without protection, for use when calculating the amount of benefit associated with the protection component of averted loss offsets. In circumstances such as when a jurisdictional offset policy applies to most impacts, plausible estimates of averted loss can be very low. Averting further loss of biodiversity is desirable, and averted loss offsets can be a valid approach for generating tangible gains. However, overestimation of averted loss benefits poses a major risk to biodiversity.

Maximizing habitat connectivity in the mitigation hierarchy. A case study on three terrestrial mammals in an urban environment

Environmental policies and the objective of no net loss highlight the importance of preserving ecological networks to limit the fragmentation of natural habitats and biodiversity loss, especially due to urbanization. In the environmental impact assessment context, habitat connectivity and the spatio-temporal dynamics of biodiversity are crucial to obtaining reliable predictions that can support decision-making. We propose a methodological framework 1) to quantify the overall impact of a development project on the functioning of an ecological network, and 2) to select the best locations for implanting new habitat patches intended to enhance landscape connectivity. The amount of reachable habitat concept was applied to three representative terrestrial mammal species: the red squirrel, the Eurasian badger and the European hedgehog. All three species are recognized as vulnerable to human pressures and potentially affected by the construction of a new stadium in our study site, Lyon (Southern France). The method combines the species distribution model Maxent with the landscape functional connectivity model Graphab. The results showed that using any one of the avoidance and reduction measures on its own was unsuccessful in achieving the objective of no net loss when habitat connectivity is considered. However, the combination of new habitat patches and corridors offered a higher gain than distinct measures. This is especially important in the short term, when new hedgerow plantations have not yet developed enough to be used by the target species. Our findings indicate, first, the need to take the temporal scale into account in environmental impact assessment. We also show that applying the optimal scenario, constructed using a cumulative patch addition followed by a similar process testing a set of potential land-use changes, maximizes habitat connectivity. Our methodology provides a useful tool to increase target species' habitat connectivity within the mitigation hierarchy and to enhance development project design for increased environmental efficiency.

Using conservation science to advance corporate biodiversity accountability

Biodiversity declines threaten the sustainability of global economies and societies. Acknowledging this, businesses are beginning to make commitments to account for and mitigate their influence on biodiversity and report this in sustainability reports. We assessed the top 100 of the 2016 Fortune 500 Global companies' (the Fortune 100) sustainability reports to gauge the current state of corporate biodiversity accountability. Almost half (49) of the Fortune 100 mentioned biodiversity in reports, and 31 made clear biodiversity commitments, of which only 5 were specific, measureable, and time bound. A variety of biodiversity-related activities were disclosed (e.g., managing impacts, restoring biodiversity, and investing in biodiversity), but only 9 companies provided quantitative indicators to verify the magnitude of their activities (e.g., area of habitat restored). No companies reported quantitative biodiversity outcomes, making it difficult to determine whether business actions were of sufficient magnitude to address impacts and were achieving positive outcomes for nature. Conservation science can advance approaches to corporate biodiversity accountability by helping businesses make science-based biodiversity commitments, develop meaningful indicators, and select more targeted activities to address business impacts. With the biodiversity policy super year of 2020 rapidly approaching, now is the time for conservation scientists to engage with and support businesses in playing a critical role in setting the new agenda for a sustainable future for the planet with biodiversity at its heart.