International principles and standards for the practice of ecological restoration. Second edition

The Society for Ecological Restoration (SER) is an international non-profit organization with members in 70 countries. SER advances the science, practice and policy of ecological restoration to sustain biodiversity, improve resilience in a changing climate, and re-establish an ecologically healthy relationship between nature and culture. SER is a dynamic global network, linking researchers, practitioners, land managers, community leaders and decision-makers to restore ecosystems and the human communities that depend on them. Via its members, publications, conferences, policy work, and outreach, SER defines and delivers excellence in the field of ecological restoration. Document development. International Principles and Standards for the Practice of Ecological Restoration (the Standards) was developed through consultation with professionals within the Society for Ecological Restoration and their peers in the global scientific and conservation communities. The first edition was launched in 2016 at the United Nations Biodiversity Conference in Cancún, Mexico. This event brought together key stakeholders from across the international policy arena, many of whom had been instrumental in driving the global initiatives to implement large-scale environmental restoration programs. Because the Standards were written as a living document to be modified and expanded through consultation and use by stakeholders, the launch included an open invitation for stakeholder input, to both improve the document and promote broad use. Subsequently, over a multi-year consultation period, SER invited input and review from a diverse spectrum of people and organizations contributing to ecological restoration. Key stakeholders contacted for comment included the secretariats of the Convention on Biological Diversity (CBD), United Nations Convention to Combat Desertification (UNCCD) including its Science-Policy Interface, Global Environment Facility, the World Bank, and members of the Global Partnership on Forest Landscape Restoration (GPFLR). In 2017, SER partnered with the IUCN Commission on Ecosystem Management to deliver an invited Forum on Biodiversity and Global Forest Restoration at which the SER Standards were reviewed (SER and IUCN-CEM 2018). SER also organized a symposium on the SER Standards and an open Knowledge Café at the 2017 SER World Conference on Ecological Restoration. Additional input was received at other events, including the 9th Ecosystem Services Partnership World Conference in Shenzhen, China in 2017. To capture the perspectives of the SER community, SER invited online feedback via its website and sent an online survey to SER members, affiliates, and stakeholders. SER has also considered and responded to feedback from published critiques in its journal, Restoration Ecology. All comments received during the consultative review process were considered in the revision process. The second edition of the Standards was approved by the SER Science and Policy Committee, and the SER Board of Directors on 18 June 2019. As with the first edition, this version will be revised and improved as the discipline evolves through science, practice, and adaptive management. The Standards are compatible with and expand on the Open Standards for the Practice of Conservation (Conservation Measures Partnership 2013) and complement the REDD+ Social and Environmental Standards (REDD+ SES 2012), and other conservation standards and guidelines. Contributors. Levi Wickwire provided assistance during document development. Karen Keenleyside contributed content to the original version. Andre Clewell's inspiration and ideas led to the attributes list and circle template (Fig. 4; Appendix 2), Kayri Havens assisted with adapting Appendix 1 on selection of seeds and other propagules, and Craig Beatty contributed to Section 4, Part 3 on global restoration initiatives. We thank the following translators of the first edition: Claudia Concha, Marcela Bustamante and Cristian Echeverría (Spanish); Ricardo Cesar (Portuguese); Narayana Bhat (Arabic); Jaeyong Choi (Korean); Junguo Liu (Chinese); and, Jean-François Alignan, Julie Braschi, Élise Buisson, Jacqueline Buisson, Manon Hess, Renaud Jaunatre, Maxime Le Roy, Sandra Malaval, and Réseau d'Échanges et de Valorisation en Écologie de la Restauration (REVER) (French). Reviewers. Many international experts provided suggestions for development of the second edition. We acknowledge many here, but may have unintentionally missed some individuals. The views expressed here are those of the authors, and not necessarily those of the reviewers. Sasha Alexander, Mariam Akhtar-Schuster, Craig Beatty, María Consuelo de Bonfil, Karma Bouazza, Elise Buisson, Andre Clewell, Jordi Cortina, Donald Falk, Marco Fioratti, Scott Hemmerling, Richard Hobbs, Karen Holl, Berit Köhler, Nik Lopoukhine, Graciela Metternicht, Luiz Fernando Moraes, Stephen Murphy, Michael Perring, David Polster, Karel Prach, Anne Tolvanen, Alan Unwin, Ramesh Venkataraman, Steve Whisenant, Andrew Whitley, and Shira Yoffe provided critical reviews. The published manuscript greatly benefited from peer review by Karel Prach, Vicky Temperton, and Joy Zedler. Their assistance, dedication, and timeliness in reviewing the manuscript was unparalleled. Participants at the SER and IUCN-CEM Forum on Biodiversity and Global Forest Restoration, Iguassu Falls, Brazil, 2017 helped clarify the scope and context of the SER Standards: Angela Andrade, James Aronson, Rafael Avila, Brigitte Baptiste, Rubens de Miranda Benini, Rachel Biderman, Blaise Bodin, Consuelo Bonfil, Magda Bou Dagher Kharrat, MiHee Cho, Youngtae Choi, Jordi Cortina, Kingsley Dixon, Giselda Durigan, Cristian Echeverría, Steve Edwards, George Gann, Manuel R. Guariguata, Yoly Gutierrez, James Hallett, Ric Hauer, Karen Holl, Fangyuan Hua, Paola Isaacs, Justin Jonson, Won-Seok Kang, Agnieszka Latawiec, Harvey Locke, James McBreen, Tein McDonald, Paula Meli, Jean Paul Metzger, Miguel A. Moraes, Ciro Moura, Cara Nelson, Margaret O'Connell, Aurelio Padovezi, Hernán Saavedra, Catalina Santamaria, Gerardo Segura Warnholtz, Kirsty Shaw, Nancy Shaw, Bernardo Strassburg, Evert Thomas, José Marcelo, Alan Unwin, Liette Vasseur, Joseph Veldman, Bethanie Walder, and Jorge Watanabe. Participants at the Knowledge Café on the International Standards, 2017 SER World Conference on Ecological Restoration, Iguassu Falls, Brazil included Mitch Aide, Rafael Carlos Ávila-Santa Cruz, Suresh Babu, Blaise Bodin, Craig Beatty, Steve Edwards, George Gann, Angelita Gómez, Emily Gonzales, Justin Jonson, Marion Karmann, Tein McDonald, Cara Nelson, Antonio Ordorica, Claudia Padilla, Liliane Parany, David Polster, Catalina Santamaria, Bethanie Walder, Andrew Whitley, Paddy Woodworth, and Gustavo Zuleta. Feedback on the published first edition. Valuable comments were received from Constance Bersok, Kris Boody, Zoe Brocklehurst, Elise Buisson, Peter Cale, David Carr, Michael Rawson Clark, Andre Clewell, Adam Cross, Maria del Sugeyrol Villa Ramirez, Rory Denovan, Giselda Durigan, Rolf Gersonde, Emily Gonzales, Diane Haase, Ismael Hernández Valencia, Eric Higgs, Sean King, Beatriz Maruri-Aguilar, Rob Monico, Michael Morrison, Stephen Murphy, Tom Nedland, J.T. Netherland, Samira Omar, David Ostergren, Glenn Palmgren, Jim Palus, Aviva Patel, David Polster, Jack Putz, Danielle Romiti, George H. Russell, David Sabaj-Stahl, Raj Shekhar Singh, Nicky Strahl, Tobe Query, Edith Tobe, Michael Toohill, Daniel Vallauri, Jorge Watanabe, Jeff Weiss, William Zawacki, and Paul Zedler. Cassandra Rosa compiled detailed notes and reviewed comments from >100 respondents of the SER survey on the Standards. Ecological restoration, when implemented effectively and sustainably, contributes to protecting biodiversity; improving human health and wellbeing; increasing food and water security; delivering goods, services, and economic prosperity; and supporting climate change mitigation, resilience, and adaptation. It is a solutions-based approach that engages communities, scientists, policymakers, and land managers to repair ecological damage and rebuild a healthier relationship between people and the rest of nature. When combined with conservation and sustainable use, ecological restoration is the link needed to move local, regional, and global environmental conditions from a state of continued degradation, to one of net positive improvement. The second edition of the International Principles and Standards for the Practice of Ecological Restoration (the Standards) presents a robust framework for restoration projects to achieve intended goals, while addressing challenges including effective design and implementation, accounting for complex ecosystem dynamics (especially in the context of climate change), and navigating trade-offs associated with land management priorities and decisions. The Standards establish eight principles that underpin ecological restoration. Principles 1 and 2 articulate important foundations that guide ecological restoration: effectively engaging a wide range of stakeholders, and fully utilizing available scientific, traditional, and local knowledge, respectively. Principles 3 and 4 summarize the central approach to ecological restoration, by highlighting ecologically appropriate reference ecosystems as the target of restoration and clarifying the imperative for restoration activities to support ecosystem recovery processes. Principle 5 underscores the use of measurable indicators to assess progress toward restoration objectives. Principle 6 lays out the mandate for ecological restoration to seek the highest attainable recovery. Tools are provided to identify the levels of recovery aspired to and to track progress. Principle 7 highlights the importance of restoration at large spatial scales for cumulative gains. Finally, ecological restoration is one of several approaches that address damage to ecosystems and Principle 8 clarifies its relationships to allied approaches on a "Restorative Continuum". The Standards highlight the role of ecological restoration in connecting social, community, productivity, and sustainability goals. The Standards also provide recommended performance measures for restorative activities for industries, communities, and governments to consider. In addition, the Standards enhance the list of practices and actions that guide practitioners in planning, implementation, and monitoring activities. The leading practices and guidance include discussion on appropriate approaches to site assessment and identification of reference ecosystems, different restoration approaches including natural regeneration, consideration of genetic diversity under climate change, and the role of ecological restoration in global restoration initiatives. This edition also includes an expanded glossary of restoration terminology. SER and its international partners produced the Standards for adoption by communities, industries, governments, educators, and land managers to improve ecological restoration practice across all sectors and in all ecosystems, terrestrial and aquatic. The Standards support development of ecological restoration plans, contracts, consent conditions, and monitoring and auditing criteria. Generic in nature, the Standards framework can be adapted to particular ecosystems, biomes, or landscapes; individual countries; or traditional cultures. The Standards are aspirational and provide tools that are intended to improve outcomes, promote best practices, and deliver net global environmental and social benefits. As the world enters the UN Decade on Ecosystem Restoration (2021–2030), the Standards provide a blueprint for ensuring ecological restoration achieves its full potential in delivering social and environmental equity and, ultimately, economic benefits and outcomes. Table of Contents SECTION 1 – INTRODUCTION6 Ecological Restoration as a Means of Improving Biodiversity and Human Wellbeing and Its Role in Broader Global Initiatives6 Need for Principles and Standards6 Background6 What's New in This Version?7 Key Definitions and Terms7 Underpinnings Assumptions7 SECTION 2 – EIGHT PRINCIPLES THAT UNDERPIN ECOLOGICAL RESTORATION8 Principle 1. Ecological Restoration Engages Stakeholders8 Principle 2. Ecological Restoration Draws on Many Types of Knowledge9 Principle 3. Ecological Restoration Practice Is Informed by Native Reference Ecosystems, while Considering Environmental Change11 Principle 4. Ecological Restoration Supports Ecosystem Recovery Processes14 Principle 5. Ecosystem Recovery Is Assessed against Clear Goals and Objectives, Using Measurable Indicators15 Principle 6. Ecological Restoration Seeks the Highest Level of Recovery Attainable17 Principle 7. Ecological Restoration Gains Cumulative Value when Applied at Large Scales18 Principle 8. Ecological Restoration Is Part of a Continuum of Restorative Activities21 SECTION 3 – STANDARDS OF PRACTICE FOR PLANNING AND IMPLEMENTING ECOLOGICAL RESTORATION PROJECTS23 SECTION 4 – LEADING PRACTICES28 Part 1. Developing Reference Models for Ecological Restoration28 Part 2. Identifying Appropriate Ecological Restoration Approaches29 Part 3. The Role of Ecological Restoration in Global Restoration Initiatives31 SECTION 5—GLOSSARY OF TERMS33 APPENDIX 1. SELECTION OF SEEDS AND OTHER PROPAGULES FOR RESTORATION41 Genetic Considerations for Sourcing Seeds or other Propagules41 Propagule Sourcing and Climate Change42 Tools and Future Directions42 Restoring Connectivity and Assisting Migration44 APPENDIX 2. BLANK PROJECT EVALUATION TEMPLATES (FOR PRACTITIONER USE)45 The International Principles and Standards for the Practice of Ecological Restoration (the Standards) provide a guide to practitioners, operational personnel, students, planners, managers, regulators, policymakers, funders, and implementing agencies involved in restoring degraded ecosystems across the world—whether terrestrial, freshwater, coastal, or marine. They place ecological restoration into a global context, including its role in recovering biodiversity and improving human wellbeing11 Terms in boldface are defined in the Glossary section. in times of rapid global change. Humanity recognizes the planet's native ecosystems as having irreplaceable ecological, societal, and economic value. In addition to their intrinsic value, such as biodiversity and spiritual or aesthetic importance, healthy native ecosystems assure the flow of ecosystem services. These services include: provision of clean water and air, healthy soils, culturally important artifacts, and the food, fiber, fuel, and medicines essential for human health, wellbeing, and livelihoods. Native ecosystems can also reduce the effects of natural disasters and mitigate accelerated climate change. Ecosystem degradation, damage, and destruction (hereafter, collectively referred to as degradation) diminish the biodiversity, functioning, and resilience of ecosystems, which in turn negatively affects the resilience and sustainability of social–ecological systems. Although protecting remaining native ecosystems is critical to conserving the world's natural and cultural heritage, protection alone is insufficient, given past and current degradation. To respond to current global environmental challenges and to sustain the flow of ecosystem services and goods essential for human wellbeing, global society must secure a net gain in the extent and functioning of native ecosystems by investing not only in environmental protection, but also in environmental repair including ecological restoration. This repair must be implemented at multiple scales to achieve measurable effects worldwide. Awareness of the need for environmental repair is growing, resulting in a global escalation of ecological restoration and related efforts (see also Section 4, Part 3). For example, the United Nations (UN) Sustainable Development Goals (SDGs) for 2030 call for restoration of marine and coastal ecosystems (Goal 14) and terrestrial ecosystems (Goal 15) that have been degraded to "protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss." The Convention on Biological Diversity (2016) calls for the "restoration of degraded natural and semi-natural ecosystems, including in urban environments, as a contribution to reversing the loss of biodiversity, recovering connectivity, improving ecosystem resilience, enhancing the provision of ecosystem services, mitigating and adapting to the effects of climate change, combating desertification and land degradation, and improving human well-being while reducing environmental risks and scarcities." And, the United Nations General Assembly has declared 2021–2030 the "Decade on Ecosystem Restoration." The concept of restoration in many of these initiatives and agreements is very broad and includes many approaches to ecosystem management and nature-based solutions, all of which are valuable. The Standards address the relationship between ecological restoration and other ecosystem management and nature-based solutions, and clarify the specific role of ecological restoration in contributing to the goals of conserving biodiversity and improving human wellbeing worldwide. Repairing degraded ecosystems is a complex task requiring significant time, resources, and knowledge. Ecological restoration contributes in substantial ways to protecting biodiversity and human wellbeing, but many restoration projects and programs, however well intentioned, have underperformed. The Standards recognize that appropriate design; good planning and implementation; sufficient knowledge, skill, effort and resources; understanding of specific social contexts and risks; appropriate stakeholder involvement; and adequate monitoring for adaptive management will contribute to improved outcomes. Application of principles and standards can increase effectiveness of ecological restoration efforts by establishing criteria for technical implementation across different ecosystem types. They also provide a framework that engages stakeholders and respects socio-cultural realities and needs, which can be applied to both mandatory (i.e. required as part of consent conditions) and non-mandatory restoration (i.e. the voluntary repair of damage). These criteria can improve ecological restoration outcomes, whether used to guide agencies, companies, or individuals engaged in planning, implementation, and monitoring; to guide regulators in developing agreements for mandatory restoration and evaluating whether those agreements have been met; or to guide policymakers in designing, supporting, funding, and evaluating restoration projects at any scale. Thus, the use of clear and carefully considered principles and standards underpinning ecological restoration can reduce the risk of unintended damage to ecosystems and native biodiversity, and help to develop high-quality projects and programs amenable to monitoring and assessment. This document expands upon and joins SER's collection of foundation documents including the SER International Primer on Ecological Restoration (SER 2004), Guidelines for Developing and Managing Restoration Projects (Clewell et al. 2005), Ecological Restoration—a Means of Conserving Biodiversity and Sustaining Livelihoods (Gann & Lamb 2006), and Ecological Restoration for Protected Areas: Principles, Guidelines and Best Practices (Keenleyside et al. 2012). It also utilizes SER's Code of Ethics (SER 2013) and specifically draws on material and models in the two editions of National Standards for the Practice of Ecological Restoration in Australia (McDonald et al. 2016a, 2018). Several books were influential including Restoration Ecology: The New Frontier (Van Andel & Aronson 2012), Ecological Restoration: Principles, Values and Structure of an Emerging Profession (Clewell & Aronson 2013), Foundations of Restoration Ecology (Palmer et al. 2016), Routledge Handbook of Ecological and Environmental Restoration (Allison & Murphy 2017), and Management of Ecological Rehabilitation Projects (Liu & Clewell 2017). We have drawn content from the editorial Ecosystem Restoration is Now a Global Priority (Aronson & Alexander 2013), and the policy documents Ecosystem Restoration: Short-term Action Plan of the CBD (Convention on Biological Diversity 2016), Partnering with Nature: The Case for Natural Regeneration in Forest and Landscape Restoration (Chazdon et al. 2017), and Restoring Forests and Landscapes: The Key to a Sustainable Future by the Global Partnership on Forest and Landscape Restoration (GPFLR; Besseau et al. 2018). Works published in SER's journal Restoration Ecology, book series on The Science and Practice of Ecological Restoration (Island Press), and Restoration Resource Center, as well as many other documents have informed development of this edition. While Sections 1 through 3 are mostly free of references for brevity's sake, Section 4 (Leading Practices), Appendix 1, and Supplement S1 include citations. To better address the diverse roles people play in restoration and how the goals of Indigenous groups fit into the overall picture of ecological restoration, we have reorganized the Principles to better incorporate social-economic and cultural factors that can greatly affect outcomes of restoration. Principle 1 expands on social goals and includes a "Social Benefits Wheel" tool to help convey social targets and goals of a project. Principles and Key Concepts are merged into a single section on Principles. A compilation of historical documents used to synthesize the Principles is provided in Supplement S1. Scaling-up ecological restoration and the relationship between ecological restoration and allied activities included in Section 4 of the first edition are incorporated into Principles 7 and 8 in this version. Key topics related to reference models and restoration approaches are included in a new section on Leading Practices (Section 4), which also considers integration of ecological restoration into global restoration initiatives. We added a technical appendix on sourcing of seeds and other propagules for restoration. SER defines ecological restoration as the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed. It is distinct from restoration ecology, the science that supports the practice of ecological restoration, and from other forms of environmental repair in seeking to assist recovery of native ecosystems and ecosystem integrity. Ecological restoration aims to move a degraded ecosystem to a trajectory of recovery that allows adaptation to local and global changes, as well as persistence and evolution of its component species. Ecological restoration is commonly used to describe both the process and the outcome sought for an ecosystem, but the Standards reserve the term restoration for the activity undertaken and recovery for the outcome sought or achieved. The Standards define ecological restoration as any activity with the goal of achieving substantial ecosystem recovery relative to an appropriate reference model, regardless of the time required to achieve recovery. Reference models used for ecological restoration projects are informed by native ecosystems, including many traditional cultural ecosystems (see Principle 3). Ecological restoration projects or programs include one or more targets that identify the native ecosystem to be restored (as informed by the reference model), and project goals that establish the level of recovery sought. Full recovery is defined as the state or condition whereby, following restoration, all key ecosystem attributes closely resemble those of the reference model. These attributes include absence of threats, species composition, community structure, physical conditions, ecosystem function, and external exchanges. Where lower levels of recovery are planned or occur due to resource, technical, environmental, or social constraints, recovery is referred to as partial recovery. An ecological restoration project or program should aspire to substantial recovery of the native biota and ecosystem functions (contrast with rehabilitation below). When full recovery is the goal, an important benchmark is when the ecosystem demonstrates self-organization. At this stage, if unexpected barriers or lack of particular species or processes take recovery off course, further restoration actions may be required to ensure that the trajectory ultimately continues toward full recovery. Once fully recovered, any ongoing activities (e.g. to maintain disturbance regimes) would be considered ecosystem maintenance or management. Specific activities, such as prescribed fire or the control of invasive species, may be used in both restoration and maintenance phases of a project. The goal of rehabilitation projects is not native ecosystem recovery, but rather reinstating a level of ecosystem functioning for renewed and ongoing provision of ecosystem services potentially derived from nonnative ecosystems as well. Rehabilitation is one of many restorative activities aligned along a continuum that includes ecological restoration and its allied and complementary activities, all of which contribute to improving ecosystem integrity and social–ecological resilience (see Principle 8). A few assumptions about the role of ecological restoration underpin the Standards. First, restoration of most native ecosystems is a challenging process, and substantial recovery usually requires long periods of time. Consequently, many ecological restoration projects are still far from achieving the levels of biodiversity, ecosystem functioning, and delivery of services of intact ecosystems. Thus, while compensation may be mandated as a result of ecosystem loss or degradation, the potential for ecological restoration should never be invoked as a justification for destroying or damaging existing native ecosystems or for unsustainable use. Similarly, any potential to translocate rare species should not be used to justify destruction of existing intact habitat. Where compensation is mandated, however, the level of compensation should be far in excess of the estimated ecosystem loss or degradation, and care should be exercised to ensure offsets do not cause additional degradation. Second, the Standards clarify the use of a native reference ecosystem as a model for the ecosystem being restored. The reference model, derived from multiple sources of information, aims to characterize the condition of the ecosystem as it would be had it not been degraded, adjusted as necessary to accommodate changed or predicted change in biotic or environmental conditions (e.g. climate change). The Standards also make clear that appropriate reference models for ecological restoration are not based on immobilizing an ecological community at some past point in time, but rather increasing potential for native species and communities to recover and continue to reassemble, adapt, and evolve. Finally, ecological restoration is part of a larger set of ecosystem management practices designed to conserve and, where appropriate, sustainably utilize native ecosystems. These practices range from regenerative agriculture, fisheries, and forestry to ecological engineering, including those invoked in the Convention on Biological Diversity, the United Nations 2030 Sustainable Development Goals, and by Forest Landscape Restoration (FLR) projects and a multitude of local and regional programs. As such, ecological restoration complements other conservation activities and nature-based solutions and vice versa. The following Principles provide a framework to explain, define, guide, and measure the activities and outcomes of ecological restoration practice (Fig. 1). They represent a distillation of principles and concepts presented in SER foundational documents, scientific literature, and practitioner experience (Appendix S1). Ecological restoration is undertaken for many reasons including to recover ecosystem integrity and to satisfy personal, cultural, social-economic, and ecological values. This combination of ecological and social benefits can lead to improved social–ecological resilience. Humans benefit from a closer and reciprocal engagement with nature. Participating in restoration projects can be transformative, for example, when children involved in restoration projects develop personal ownership over restoration sites, or when community volunteers seek new career or vocational paths in restoration practice or science. Communities located within or near degraded ecosystems may gain health and other benefits from restoration that improves the quality of air, land, water, and habitats for native species. Indigenous peoples and local communities (both rural and urban) benefit where restoration reinforces nature-based cultures, practices, and livelihoods (e.g. subsistence fishing, hunting, and gathering). In addition, restoration can provide short-term and long-term employment opportunities for local stakeholders, creating positive ecological and economic feedback loops. Stakeholders can make or break a project. Recognizing the expectations and interests of stakeholders and directly involving them is key to ensuring that both nature and society mutually benefit. Stakeholders can help prioritize distribution of restoration actions across the landscape, set project goals (including desired level of recovery), contribute knowledge about ecological conditions and successional patterns to improve development of reference models, and engage in participatory monitoring. Additionally, stakeholders can provide political and financial support for long-term project sustainability, as well as moderating conflicts or disagreements that may arise. Recognition of diverse forms of property ownership and managem