Biodiversity and Climate Change Assessment: Review of Draft Chapters (2025)
Chapter: 2 Assessing Biodiversity and Climate Change
2
Assessing Biodiversity and Climate Change
Scientific assessments provide a solid foundation of knowledge for management and policy decisions by synthesizing scientific understanding. For biodiversity and climate change specifically, assessments bring together available knowledge and help to anticipate implications for ecosystem and human health, natural resources, and livelihoods. Further, these assessments can inform decisions and tradeoffs around natural resource management and evaluate approaches that promote thriving ecosystems and societies. Considering the implications for food, water, and other critical resources upon which society depends, the pace and scale of changes in biodiversity and climate warrant strong attention within North America and globally. The Committee commends the USGS and the international authoring team for developing an assessment focused on these issues within Canada, the U.S., and Mexico, and across borders. This new assessment will make an important contribution to understanding and addressing changes in biodiversity and climate in this region and serves as an important input to forthcoming related assessments.
Developing an assessment that captures the expansive and complex relationship between biodiversity and climate change requires a strong foundational structure and approach that synthesizes materials in an effective manner to reach intended audiences. A robust history of international scientific assessments focused on climate change and biodiversity demonstrates the importance of assessments addressing these topics and provides a solid foundation for new assessment development. These assessments provide value in a variety of ways. For instance, some assessments are developed at regular intervals and build on prior work to capture advancements and continued synthesis over time while others are developed as one-off assessments that may focus on a specific topic or region and serve as both standalone resources and inputs to other assessment efforts. The IPCC, established in 1988, and IPBES, established in 2012, have both published a suite of assessments focused on climate change and biodiversity and ecosystem services, respectively. In late 2020, IPCC and IPBES co-sponsored a landmark workshop to examine common ground and goals and opportunities to address these issues together. The workshop brought together scientific communities and encouraged policy makers to pursue synergies or trade-offs between biodiversity protection and climate change mitigation and adaptation. See Pörtner et al. (2021) for a summary of this workshop. The 2022 IPCC Working Group 2 Assessment, Climate Change 2022: Impacts, Adaptation, and Vulnerability (IPCC 2022), focused particularly on ecosystems and biodiversity, particularly in the Summary for Policymakers. The IPBES Nexus Assessment (2024) also clearly focuses on biodiversity and climate interlinkages. These efforts and others provide a strong foundation of knowledge about effective approaches to developing an assessment on these complex and intertwined topics.
The Committee found many opportunities to strengthen the draft BCCA, including improvements that will be most useful if applied broadly across the chapters of the assessment. This chapter of the Committee’s report provides detailed guidance on addressing these overarching aspects of the assessment. The review Committee encourages the BCCA chapter author teams to consider where this guidance can be applied throughout their chapters. The Committee views the areas highlighted for improvement in this chapter to be essential considerations for any biodiversity and climate change assessment, so this material can also serve as guiding principles more generally for future assessments focused on these topics. References are provided as general background and to guide the BCCA authors to materials relevant for responding to specific aspects of this review for inclusion in their assessment.
BIODIVERSITY AND CLIMATE CHANGE ARE INEXTRICABLY LINKED
An extensive base of knowledge offers a solid foundation to synthesize understanding of changes in biodiversity and climate. Published scientific research, Indigenous Knowledge, and Local Ecological Knowledge have documented strong connections between biodiversity and climate change, including impacts of human-caused climate change on biodiversity, benefits of biodiversity for reducing climate change, and driving forces affecting both climate and biodiversity (IPCC 2022). The intertwined nature of these connections has been considered since concerns about human-driven increases in greenhouse gases first emerged (e.g., Conservation Foundation 1963; Peters 1988; Peters and Darling 1985). Changes in climatic conditions influence species distributions, the types and direction of species interactions (e.g., predation, competition), and the environment in which communities of organisms function (Bellard et al. 2012; Grimm et al. 2013; Habibullah et al. 2021). At the same time, biodiversity affects attributes of climate. In the realm of climate mitigation, ecosystems play a major role in storing carbon and removing greenhouse gases from the atmosphere (Griscom et al. 2017). In the realm of climate adaptation, biodiversity can enhance the ability for human enterprises to adapt. For example, biodiversity provides pollination services to benefit climate-stressed agriculture (Ortiz et al. 2021). As climate change proceeds, with risks projected to increase, refining our understanding of the intertwined nature of biodiversity and climate change is critical. Concurrent with better understanding of the science, it is important to identify effective policy and management approaches that take climate change and biodiversity into account together, which historically has not often been undertaken (Jönsson and Purvis 2022).
Conclusion 2.1: A robust scientific assessment of the multiple interactions between biodiversity and climate change can provide key information as input to effective resource management policies and decisions that benefit society.
The draft BCCA chapters have provided much of the groundwork for synthesizing the science and providing information that could be useful in decision-making. Building on this material by following the guidance throughout this review report will further realize its potential to be an influential and useful document.
KEY FEATURES OF ROBUST SCIENTIFIC ASSESSMENTS
Scientific assessments are unique from other scientific documents in that they evaluate the breadth of available information and synthesize and prioritize evidence rather than providing an exhaustive literature review. Assessments generally undergo a rigorous development process to ensure scientific integrity, information quality, transparency, and reproducibility of methods used, and they can be updated over time to synthesize the latest scientific findings. Many guidance documents now provide standardized rules, language guidance, and
other information to aid in developing assessments and providing consistency in approach (e.g., IPBES 2018a; STACCWG 2021; United Nations Environment Program Global Environment Outlook process).
Develop a Strong Conceptual Framework
Central to the development of an effective assessment is the creation of a conceptual framework that is adopted across the entire document. Scientific assessments of biodiversity and climate change interactions require strong conceptual frameworks that establish clear narrative structures and articulate complex topics and diverse knowledge streams. These frameworks serve multiple critical functions: they provide logical organization within and across chapters; they provide a foundation to include comprehensive coverage of key ecosystems and processes; they can be used to establish a consistent approach to addressing uncertainty; and they can help to facilitate clear, consistent communication of key messages. A well-designed conceptual framework ultimately serves as both a structural scaffold and an intellectual guide, ensuring that the assessment effectively bridges the science-policy interface while maintaining scientific rigor and practical utility for all intended audiences.
The draft BCCA lacks a consistent conceptual framework across chapters. This makes it difficult for readers to understand the selection, prioritization, and organization of included material. Chapter 1 of the draft BCCA explains that the IPBES framework is being used, yet it has not been modified to effectively capture the full scope of both biodiversity and climate change. Draft Chapter 4 in the BCCA is most effective in its approach to framing presented materials (see the BCCA Chapter 4 review in Chapter 3 of this report). An enhanced conceptual framework applied across the BCCA would establish clear principles for: 1) maintaining consistent coverage of ecosystem types (see Broad Inclusion of Ecosystems section later in this chapter of the Committee’s report); 2) balancing local, regional, and national perspectives; 3) synthesizing multiple evidence sources; and 4) connecting findings to specific audience needs. This structure would help ensure the assessment serves its intended function as an authoritative synthesis rather than a literature review. While space constraints inevitably limit coverage in any assessment, an effective framework can keep focus and explicitly acknowledge what is and is not included while providing guideposts for use of information. For instance, guidance on how to approach the challenge of considering local contexts within broader patterns might be outlined and tied to higher level discussions covered more extensively in the assessment.
In addition to IPBES, there are several other recent major assessments that provide valuable models for conceptual framework development that can be used to guide development of future assessments. These assessments include those from IPCC, the IPBES-IPCC co-sponsored workshop publication (Pörtner et al. 2021), the Royal Society’s 2021 analysis of climate-biodiversity linkages (The Royal Society 2021), and the Fifth U.S. National Climate Assessment (USGCRP 2023). Importantly, comprehensive assessment frameworks synthesize multiple knowledge systems, weaving together insights from available Indigenous Knowledge, Local Ecological Knowledge, and Western scientific approaches (see the Weaving Together Multiple Ways of Knowing section later in this chapter of the Committee’s report). This knowledge synthesis strengthens the assessment’s relevance and applicability across diverse contexts and provides a more holistic understanding of concepts while acknowledging different ways of viewing human-nature relationships.
Conclusion 2.2: A strong conceptual framework is foundational to developing an effective assessment that prioritizes key messages and logically connects materials across the report.
Evaluate the Science
In the vast breadth of literature that could be considered for inclusion in a biodiversity and climate change assessment, and with large authoring teams on these types of reports, it is essential to have clear and consistent
guidelines for what raises to the level of inclusion in the assessment and how that information is incorporated into the conceptual framework, synthesized, and presented. In the first order draft of the BCCA that the Committee reviewed, the approach to synthesis is not clearly articulated and the synthesis itself had not yet taken place given the relatively early stage of development.
Some parts of the draft BCCA require more careful consideration of what warrants inclusion in the assessment. Generally, information should not be included if a disclaimer is needed to indicate there is little available in the literature to support the statement(s). Additionally, when different sources present different terminologies or approaches, those should be evaluated and explained as appropriate.
Another key aspect to evaluating the science is to provide clear information about how scientific uncertainty is treated in the assessment (see the Treatment of Uncertainty subsection later in this chapter). This includes providing standardized descriptions of confidence and likelihood which are then applied consistently to the assessment’s findings and conclusions. Key messages are expected to be distilled from findings across multiple sources.
Conclusion 2.3: A large body of existing literature provides guidelines for developing effective assessments, including those for biodiversity and climate change. Guidance includes how to synthesize available evidence, identify knowledge gaps, and address uncertainties. Learning from and building on this guidance strengthens any assessment.
Write for Intended Audiences
The development of an effective assessment includes explicit identification of the assessment’s intended audience(s). The BCCA would benefit from clear articulation of who this assessment is meant to reach. Audience decisions influence the approach to the conceptual framework development and what is included in the front matter of the assessment to guide the reader, and also informs the language used in key messages and visualizations throughout the report. Generally, for biodiversity and climate change assessments, key audiences typically include national policymakers, resource managers (subnational, personal, and private, e.g., farmers, ranchers, and other large landowners), protected area administrators, and the broader public. Other audiences who could benefit from an assessment include the philanthropic sector, particularly organizations such as the Biodiversity Funders Group, and national development agencies, which play crucial roles in supporting conservation initiatives. Particular attention to conveying information in ways that can inform transboundary collaboration across jurisdictional boundaries—from local to international scales—would be useful in the draft BCCA given changes in biodiversity and climate are inherently transboundary, cross-scale processes.
Specific sections in assessments can help to guide audiences through the material. These sections can include, for instance, a summary of the entire assessment, an introductory chapter, and a synthesis chapter. Each is designed to have a unique purpose that builds on and complements the others without creating redundancy or confusion. One example for how to use these sections is to have the summary provide a compilation of key messages and information from chapter summaries, an introduction that provides a state of knowledge and common issues across the report, and a synthesis chapter that discusses gaps and future needs. The draft of the BCCA reviewed by the Committee contained an introduction that generally meets these guidelines (see review of draft BCCA Chapter 1 in Chapter 3 of this report) and an outline of a synthesis chapter (Chapter 9, also reviewed in Chapter 3 of this report). A summary had not yet been developed.
The draft BCCA contains many sections that are very complex and written in an academic tone, while other sections are overly simplistic. Depending on who the intended audiences are, portions of the assessment may be challenging to understand or use. Edits made with careful review and thought to who the intended audiences are and how accessible the material is (e.g., reducing jargon) will strengthen the impact of the report. A robust
framework can also help create concise language and limit redundancy across the document and ensure that a clear and consistent message is present. Concurrent with attention to the language, focus on the development of accompanying visualizations is important; graphics are a key element for making materials accessible to audiences and summarizing information, ultimately affecting how influential a report can be.
Conclusion 2.4: Language and graphics tailored to the intended audience(s) of an assessment can be highly effective in conveying important findings and making information accessible for improving understanding and decision-making.
FOUNDATIONAL SCIENCE CONCEPTS FOR ASSESSMENTS OF BIODIVERSITY AND CLIMATE CHANGE
The development of an assessment conceptual framework requires decisions about what key scientific concepts should be of central focus in the report, and how those concepts should be explained. This section provides an overview of elements of biodiversity and climate change that the Committee thinks warrant greater attention in the draft BCCA chapters. These issues are viewed as foundational to conveying the science and providing information that can be used to inform decision-making.
Connections Between Biodiversity and Climate
Substantial scientific evidence documents the intertwined nature of biodiversity and climate change and recent, rapid changes across a range of ecosystem types. This evidence spans Indigenous Knowledge, Local Ecological Knowledge, and Western science, which complement one another to provide a more holistic understanding of how these changing aspects of the natural world interact with one another and with other stressors. To develop a comprehensive and balanced assessment of the linkages between biodiversity and climate change, it is essential to consider both the impacts of climate change on biodiversity and the effects of biodiversity on climate change mitigation and adaptation. The interactions among biodiversity conservation and climate change mitigation and adaptation can be highly complex. They are further layered within addressing societal needs such as food and housing, adding to the challenge and importance in approaching these issues in a holistic way that considers various tradeoffs.
In the draft chapters of the BCCA, discussion of biodiversity and climate change linkages focuses primarily on the impacts of climate change on biodiversity. Discussion of how biodiversity affects climate change is confined primarily to BCCA draft Chapter 6, where expanded attention to this topic and a more clearly developed narrative would be beneficial (see a more detailed review of BCCA Chapter 6 in Chapter 3 of this report). There is an extensive literature base on which to draw to expand discussion of biodiversity’s influence on climate change. The Committee draws upon this literature in this section to demonstrate the importance and value of including a more balanced treatment of these topics in the BCCA.
Anthropogenic climate change is damaging biodiversity. Research has detected changes in biodiversity and ecosystems around the world and attributed those changes to anthropogenic climate change, exacerbating changes from other stresses such as agricultural expansion, urbanization, overexploitation of natural resources, air and water pollution, dams, levees, and other engineering changes to natural hydrology, and other non-climate change factors (Cooley et al. 2022; Parmesan et al. 2022). Impacts attributed by IPCC (2022) to anthropogenic climate change include documented extinction of two animal species globally, extirpation of local populations of over 400 plant and animal species globally, upslope and latitudinal shifts of biomes, doubling of tree mortality and the area burned by wildfire in the western U.S., extensive bleaching and death of corals globally, extensive death of marine animals in heat waves globally, and others.
DEFINING WAYS OF KNOWING
Indigenous Knowledge (Canada) There is no single definition of Indigenous Knowledge. For our purposes, we understand “Indigenous Knowledge” as a term that refers to a set of complex knowledge systems based on the worldviews of Indigenous Peoples. Indigenous Knowledge reflects the unique cultures, languages, values, histories, governance and legal systems of Indigenous Peoples. It is place-based, cumulative and dynamic. Indigenous Knowledge systems involve living well with, and being in relationship with, the natural world. Indigenous Knowledge systems build upon the experiences of earlier generations, inform the practice of current generations, and evolve in the context of contemporary society. Different First Nations, Inuit and Métis communities each have distinct ways of describing their knowledge. Knowledge Holders are the only people who can truly define Indigenous Knowledge for their communities. It is important to note that some Indigenous communities are struggling to maintain their Indigenous Knowledge due to ongoing impacts of colonialism.1
Indigenous Knowledge (U.S.) is defined as a body of observations, oral and written knowledge, innovations, practices, and beliefs developed by Tribes and Indigenous Peoples. Indigenous Knowledge is a body of observations, oral and written knowledge, innovations, practices, and beliefs developed by Tribes and Indigenous Peoples through interaction and experience with the environment.2 It is applied to phenomena across biological, physical, social, cultural, and spiritual systems.3 Indigenous Knowledge can be developed over millennia, continues to develop, and includes understanding based on evidence acquired through direct contact with the environment and long term experiences, as well as extensive observations, lessons, and skills passed from generation to generation.4 Indigenous Knowledge is developed by Indigenous Peoples including, but not limited to, Tribal Nations, Native Americans, Alaska Natives, and Native Hawaiians. Each Tribe or Indigenous community has its own place-based body of knowledge that may overlap with that of other Tribes.
Indigenous Knowledge (Mexico). There is a vast literature of Indigenous Knowledge in Mexico. In general, it refers to traditional knowledge, practices, and worldviews passed down from generation to generation by Indigenous Peoples. This knowledge includes a wide variety of aspects such as culture, spirituality, governance, agriculture, traditional medicine, natural resources, and so on. Indigenous Knowledge is very complex and very variable across the country and the hundreds of local cultures.5
Local Ecological Knowledge refers to local knowledge holders, such as landowners who settled on a piece of land and have lived there for several generations.6
Western science (also called modern science, Western scientific knowledge, or international science) is used in the context of the IPBES conceptual framework as a broad term to refer to knowledge typically generated in universities, research institutions and private firms following paradigms and methods typically associated with the ‘scientific method’ consolidated in Post-Renaissance Europe on the basis of wider and more ancient roots. It is typically transmitted through scientific journals and scholarly books. Some of its central tenets are observer independence, replicable findings, systematic skepticism, and transparent research methodologies with standard units and categories.7
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1 Crown Consultation with Indigenous Peoples in federal impact assessment, see https://www.canada.ca/en/impact-assessment-agency/programs/aboriginal-consultation-federal-environmental-assessment/indigenous-knowledge-policy-framework-initiative.html.
2 U.S. Fish & Wildlife Services, (Feb. 2011), Traditional Ecological Knowledge for Application by Service Scientists, https://www.fws.gov/sites/default/files/documents/TEK-Fact-Sheet.pdf; see also Inuit Circumpolar Council (2022). Indigenous Knowledge, https://www.inuitcircumpolar.com/icc-activities/environment-sustainabledevelopment/Indigenous-knowledge.
3 U.S. Fish & Wildlife Services (Feb. 2011), Traditional Ecological Knowledge for Application by Service Scientists, see https://www.fws.gov/sites/default/files/documents/TEK-Fact-Sheet.pdf.
4 Id.
5 García A., Conocimiento Tradicional de los Pueblos Indígenas de México y Recursos Genéticos, (2007), see https://www.inpi.gob.mx/2021/dmdocuments/estudio_conocimiento_trad_de_pueblos_indigenas.pdf.
6 Gann, G.D., McDonald, T., Walder, B., Aronson, J., Nelson, C.R., Jonson, J., Hallett, J.G., Eisenberg, C., Guariguata, M.R., Liu, J., Hua, F., Echeverria, C., Gonzales, E.K., Shaw, N., Decleer, K., & Dixon, K.W., (2019), International principles and standards for the practice of ecological restoration.
7 See the IPBES glossary of terms, see https://www.ipbes.net/glossary/western-science.
At the same time, biodiversity conservation can help mitigate climate change, ensuring continued sequestration and storage of carbon in ecosystems which contributes to lessening the impacts of climate changes and risks and costs to communities. Forests, grasslands, peatlands, permafrost, ocean waters, and other ecosystems provide a vital global ecosystem service of preventing continued climate change by naturally taking up carbon in vegetation, soils, and water and preventing some of its release to the atmosphere as a greenhouse gas (e.g., Bai and Cotrufo 2022; Griscom et al. 2017; Griscom et al. 2020; Melillo et al. 2016; Nabuurs et al. 2022; Pan et al. 2024; Roberts et al. 2017). Globally, terrestrial ecosystems contain stocks of approximately 3,500 gigatons of carbon in vegetation, permafrost, and soils. This is three to five times the amount of carbon stored in unextracted coal, oil, methane, and other fossil fuels and more than four times the carbon currently in the atmosphere (Parmesan et al. 2022). Terrestrial ecosystems currently remove more carbon from the atmosphere than they emit and so are currently a net sink of carbon globally (Friedlingstein et al. 2025).
Ocean environments (coastal, open ocean, and deep sea) collectively contain carbon stocks estimated at 38,000 gigatons (Denning 2022), although this static value belies the dynamics of carbon pathways and processes. Between the early 1960s and late 2010s, approximately 25% of total anthropogenic carbon dioxide emissions were absorbed by the ocean, with uptake tripling from 1990 through 2019 (Gruber et al. 2023). However, yearly uptake varies by approximately 20%, with uptake decreasing in the future due in part to warming and acidification (Gruber et al. 2023). Biological processes such as carbon sequestration in coastal sediments and trophic transfer of carbon from pelagic to deep-sea regions via excretion by predators can influence rates of carbon transport. Disturbances from direct and indirect human impacts (e.g., to seagrass meadows, ecosystem overfishing) will reduce rates of carbon burial and transfer (Roberts et al. 2017).
Wildlife species also affect carbon movement, sequestration and storage. For example, migratory species can alter vegetation by transferring nutrients, seeds, and other organisms long distances and introducing them into other environments (Bauer and Hoye 2014), while the absence of predators in coastal ecosystems can stimulate herbivore numbers, which suppress vegetation growth and reduce carbon storage (Atwood et al. 2015). Large wild animals have also been identified as having the potential to influence climate impacts by affecting vegetation dynamics that alter the fire regime and albedo (Malhi et al. 2022) and shifting of carbon from aboveground vegetation to belowground soil pools (Berzaghi et al. 2023; Malhi et al. 2022).
Biodiversity also plays an important role in adapting to climate change for both ecosystems and societies (Bardgett et al 2021; Donovan et al. 2021, Forzieri et al 2022; Gillerot et al 2022; Irob et al 2023; Marcolin et al. 2024; Pardos et al. 2021). Ecosystems with high ecological integrity (structure, composition and function) are more resilient to climate change impacts and can withstand and recover from extreme weather events, such as floods, droughts and storms (Epple and Dunning 2014; Malhi et al. 2022; Thompson et al. 2009) as well as reduce societal risks and costs from environmental hazards and weather events (Bathurst et al., 2011; Johnson et al. 2020; Kumagai et al. 2013; Narayan et al. 2017). Forests and wetlands can play a substantial role in regulating local climates, moderating temperature, influencing precipitation patterns, and reducing urban heat island effects (Bonan 2008; Pielke et al. 1998; Sheil and Murdiyarso 2009). Ecosystems with plant and animal diversity can also be effective in maintaining soil structure and fertility, reducing the risk of erosion and land degradation resulting from climate change to protect agricultural productivity and food security (Berendse et al. 2015). Diverse ecosystems also support pollinator species (IPBES 2016; Papanikolaou et al. 2017), which are critical for food production and security in a changing climate as well as lessen the likelihood of being a source of infectious disease outbreaks arising in part from climate change (Gottdenker et al. 2014; Mahon et al. 2024; Marcolin et al. 2024).
Addressing changes in biodiversity and climate together can involve many trade-offs between climate action and biodiversity conservation. Many actions to improve biodiversity, such as protected areas, have the dual benefit of addressing climate change (Shin et al. 2022). But the reverse is not the case. Many climate change
mitigation measures, such as biofuels production, renewables siting, and monoculture afforestation (Smith et al. 2022), can harm biodiversity. Hydroelectric dams can cause enormous damage to riverine ecosystems (Reid et al. 2019). Efficient conservation of existing vegetation might be more cost effective and ecologically beneficial than restoration of degraded ecosystems through activities such as reforestation/afforestation (Cook-Patton et al. 2021). Discussion of these complexities and the implications of various trade-offs is important to informing decisions around these topics.
Conclusion 2.5: A large body of evidence documents changes in biodiversity and climate change, the linkages between them, and interactions with other factors. The Biodiversity and Climate Change Assessment can be most influential if it provides a full picture of the influence of biodiversity on climate mitigation and adaptation and climate change impacts on biodiversity.
More broadly, linkages between biodiversity and climate change cannot be studied in isolation. Many other stressors are driving biodiversity changes including overexploitation of natural resources, habitat conversion and fragmentation, and establishment of invasive species (IPBES 2018b and references therein). For example, for migratory species threatened by overexploitation and habitat destruction, climate change may alter patterns of exploitation and habitat change in the future (WCMC, 2024). Assessments of biodiversity and climate change can be most influential when they also account for the role of these other factors. Chapter 4 in the draft BCCA provides a strong description of other key stresses and their role in influencing biodiversity and climate change with effective key messages and the weaving in of Indigenous Knowledge. See the review of BCCA Chapter 4 in Chapter 3 of this report. At the same time, there are disruptive global processes that can influence both biodiversity and climate change and affect their interactions. These processes are numerous—volcanic eruptions, pandemic outbreaks, globalization trends, establishment of large-scale commercial systems, and impacts of global (micro or nano) plastic pollution.
Broad Inclusion of Ecosystems
Changes in biodiversity and climate are pervasive, affecting a wide range of organisms and ecosystem types. Biodiversity and climate change assessments are most influential when they address all ecosystems relevant to a given region of study. This captures the most complete picture of the importance of the region’s ecosystems and species and the changes they are undergoing. It also allows for exploration of how observed changes can inform mitigation, adaptation, conservation, and other planning efforts. For an assessment covering Canada, the U.S., and Mexico, discussion of terrestrial (plant, animal, microbial) and aquatic (freshwater, marine, estuarine, groundwater) ecosystems are needed. The North American Land Cover database for 2020 usefully illustrates ecoregions (Commission for Environmental Cooperation 2024). The draft BCCA would be strengthened by greater representation of the ecosystems in this region across chapters.
The draft chapters give considerable attention to animals in terrestrial ecosystems but limited explicit discussion of plant communities. Plants are foundational to conserving wildlife biodiversity, providing wildlife habitat, and sustaining food web relationships key to retaining biodiversity in all types of marine, freshwater, and terrestrial ecosystems (Eisenberg 2010).
Inland water ecosystems are also not well represented in many draft chapters of the BCCA (see, for example, individual reviews of Chapters 2.a, 2.d, 6, 8.a, and 8.d in Chapter 3 of this report) and discussion that is included is lesser in depth and breadth than that of terrestrial ecosystems. The assessment would be improved with a more robust inclusion of these ecosystems to demonstrate current understanding. Additionally, inclusion of North American examples is important to demonstrate the regional context of biodiversity and climate
change. For instance, migratory animals, transboundary issues, and trade-offs (e.g., fossil fuels vs. hydroelectric dams) can all be effectively illustrated through case studies within river basins and networks. Tidal wetlands and wetland species, which provide numerous ecosystem benefits, are also threatened by aspects of climate change such as sea-level rise.
Marine ecosystem dynamics and effects of and on fish and fisheries are missing from most sections of the draft BCCA chapters. These ecosystems are experiencing important and well-documented changes that should be captured in any biodiversity and climate change assessment (Cheung et al. 2021; Gissi et al. 2021; Ocean Panel Leaders 2023). For example, climate change influences species distributions, food webs, phenology of key species, prey and predator productivity, ecosystem processes, and the associated goods and services that benefit society such as fisheries, conservation, and carbon sequestration (Cavan and Hill 2023; du Pontavice et al. 2021; Friedland et al. 2023; van Denderen et al. 2021). It is important to also address differences in ecological settings (e.g., latitude, depth, food web structure, human uses) in assessments in a way that informs policy and management (Craig and Link 2023, Gomes et al. 2024).
Attention to local and regional ecosystems with unique attributes, experiencing particularly large changes, or with certain animal or plant groups facing greater risk of extinction, are also important to explain. For example, the southeastern U.S. is a global biodiversity hotspot for freshwater ecosystems, supporting most of the nation’s freshwater species, including the highest known diversity of freshwater mussels and crayfish worldwide. Many listed endangered or threatened animals in the U.S. are snails, crayfishes, freshwater mussels, fishes, amphibians, and reptiles, most of which are completely or partially dependent on freshwater habitats.
The draft assessment would also benefit from greater discussion of the Arctic, which comprises large areas of the U.S. and nearly 40% of the land mass of Canada. Northern high latitudes are increasing in temperature more rapidly than anywhere else on Earth (Rantanen et al. 2022) and experiencing changes to precipitation regimes (Bintanja and Andry 2017; McCrystall et al. 2021) that are accelerating permafrost thaw (Kokelj et al. 2015) and altering hydrologic regimes (Beel et al. 2021). Biodiversity concerns in this region are different than many others because Arctic ecosystems have naturally low biodiversity due to the short growing season and extreme cold temperatures. They are characterized by Arctic endemic species and a predominance of cold-tolerant and cold-stenothermic species (Meltofte 2013). Climate change is shifting species distributions in the Arctic and leading to a loss of Arctic endemic species, but the concurrent northward movement of species typically found further south will lead to a net increase in biodiversity to more closely resemble temperate ecosystems. This shift will result in loss of unique Arctic ecosystems and biodiversity, with detrimental effects (e.g., Aronsson et al. 2021; CAFF 2017; Lento et al. 2019; Meltofte 2013).
Agroecosystems, framed narrowly in the biodiversity and climate change context, are also an important ecosystem type to include in a BCCA type assessment. For instance, there are strong case studies about plant domestication led by Indigenous Peoples (e.g., maize, pumpkins, potatoes, sunflowers, Chenopodium) that have become part of the biodiversity on which humans rely. See an overview paper on this topic published by The National Commission for the Knowledge and Use of Biodiversity’s team (CONABIO; Mastretta-Yanes et al. 2018). The draft BCCA touches on agroecosystems, but could expand in this area, for example by assessing the roles of regenerative agriculture, which is based in part on the relationships and practices Indigenous Peoples have had for millennia, and Indigenous forest stewardship practices that emphasize conserving biodiversity, particularly culturally significant species of plants, in climate mitigation and adaptation (Garibaldi and Turner 2004; Parotta and Agnoletti 2012; Trosper et al. 2012). In Chapter 6 of the draft BCCA, authors could go further in discussing the biodiversity component of agroecosystems (see the BCCA draft Chapter 6 review in Chapter 3 of this report for details).
The draft BCCA, particularly draft Chapter 8.a, discusses novel ecosystems. The Committee recommends that the BCCA authors carefully consider the literature on this topic and its limitations for inclusion in the as-
sessment. It is important to closely review the evolution of literature on the concept of ecological novelty as well as the characterization of specific ecosystems as novel. Discussion of this topic, particularly in a theoretical framework, is also generally better suited for research rather than policy chapters in an assessment. See the review of BCCA draft Chapter 8.a in Chapter 3 of this report for more detailed discussion of this topic.
Conclusion 2.6: Measurements and observations have documented numerous changes in biodiversity, climate change, and interactions between them across North American ecosystems. Revising the draft Biodiversity and Climate Change Assessment to provide a more thorough representation of the range of changes in different ecosystems, particularly increasing discussion of Arctic, marine, and freshwater ecosystems, would provide necessary information for a broader audience.
Addressing Mismatches Between Ecosystem-Based and Jurisdictional Boundaries
Studying natural and social processes is inherently transboundary. Organisms, nutrients, and water move among ecosystems. People and their ideas and cultures do the same. These movements, or “flows”, depend on the dispersal ability of living organisms and on the connectivity of their habitats (e.g., landscape connectivity, flowing rivers, temporary flooding of lentic habitats and wetlands). Climate change and biotic interactions influence how species adapt to local conditions, often resulting in range shifts. Policies, laws, and regulations reflect national/state/provincial/territorial borders and protected area boundaries that do not necessarily incorporate the range of these ecological and social processes. This mismatch complicates the understanding of climate change and biotic interactions. Chapter 7 of the draft BCCA in particular focuses on movements among Canada, the U.S., and Mexico using a typology of flows and considers how climate change affects them (see details of the review of draft Chapter 7 in Chapter 3 of this report). While this approach provides a useful description of the movement of entities such as species and resources across national boundaries, it is less helpful in examining the interactions among policies, laws, and regulations across borders, and how these interactions influence the effects of climate change on biodiversity loss and vice-versa.
One alternative approach to framing discussion of transboundary issues for a biodiversity and climate change assessment is to focus on changes in species’ ranges. Species ranges can shift, contract, or expand and understanding the causes and anticipating future potential shifts are central to informing management and policy decisions. Range shifts are particularly relevant when they occur as a result of changes to the habitat template that are brought on by climate change and alter conditions beyond what the species can tolerate. In this way, climate change leads to sinks for species as they move towards areas more closely resembling the climate of their lost habitat, such as coastlines, higher elevations, and higher latitudes. This can ultimately lead to extinctions when species reach the maximum geographic extent of a possible range shift (Burrows et al. 2014). In the Arctic, this phenomenon has been referred to as the conveyor belt to extinction (Goedkoop et al. 2022) or Arctic squeeze (Aronsson et al. 2021). Applying range shift framing to invasive species movements influenced by climate change with implications for biodiversity would also be effective. Range shift framing is also helpful in a historical context; historically humans moved along with culturally significant species and availability of edible species.
Range shifts that span jurisdictional boundaries provide an opportunity for discussion of transboundary policies as well as consideration of additional factors affecting biodiversity and climate change such as the built environment and varying habitat access or protections in different jurisdictions. For example, the gopher toad, an at-risk species, relies on habitat found in multiple U.S. states which differ in their conservation policies and their listing status under the U.S. Endangered Species Act. Although complex, considering both the presence of
species across different jurisdictions and examining range shifts provide mechanisms to view biodiversity and climate change across ecosystem-based and jurisdictional boundaries, which is essential to thoroughly assessing observed change and considering policy options.
Conclusion 2.7: Ecosystems and species do not stop at borders; an assessment focused on North America, including the Biodiversity and Climate Change Assessment, provides an opportunity to convey information that informs transboundary coordination and collaboration efforts to address and manage for combined biodiversity and climate change goals.
Analyzing and Presenting the Evidence
Central to the development of any assessment is a thorough review of available information (Indigenous Knowledge, Local Ecological Knowledge, Western science), distillation of priority topics, and a synthesis of that information grounded in multiple lines of evidence. This includes summary figures, in addition to the text, that provide context and overall assessment findings. In this section, the Committee offers suggestions on some of the types of analyses and information that contribute to assessments being influential, as well as addressing uncertainty. These are areas that are viewed as generally being important to assessments of changes in biodiversity and climate, and to the BCCA specifically.
Detection and Attribution
The draft BCCA would benefit from a more rigorous examination of detection and attribution in the scientific literature. A multitude of factors can cause changes in ecosystems and biodiversity, including deforestation, agricultural expansion, hydrologic alteration, urbanization, timber harvesting, livestock grazing, oil and methane drilling, air and water pollution, coastal land-use practices, overfishing and associated gear impacts, and, most relevant to this report, anthropogenic climate change. Developing effective solutions to conserve ecosystems and biodiversity requires identifying the cause of any damage. Detection and attribution are two scientific procedures used specifically by the IPCC to distinguish among various factors to provide a scientifically robust basis for management action or policy. Detection seeks to examine whether a change is statistically significantly different from natural variation and attribution seeks to analyze the relative weights of anthropogenic climate change and other factors in causing detected changes (IPCC 2014, 2022).
For example, detection and attribution analyses have found that human-caused climate change caused a drought across the southwestern U.S. since 2000 that has been the most severe drought since the 1500s (Williams et al. 2020, 2022), doubled the average annual area burned by wildfire over natural levels across the western U.S. from 1984 to 2015 (Abatzoglou and Williams 2016), tripled the average area burned by wildfire in summer across northern and central California from 1996 to 2021 (Turco et al. 2023), increased burned area 7 to 11 times over natural levels in British Columbia, Canada, in the extreme fire season of 2017 (Kirchmei-er-Young et al. 2019), and doubled tree mortality across the West from 1955 to 2007 (van Mantgem et al. 2009). Additionally, field research has detected biome shifts at numerous sites in temperate and boreal ecosystems in North America and attributed them to anthropogenic climate change more than to other factors (Gonzalez et al. 2010; IPCC 2014). In these cases, the attribution analyses found that anthropogenic climate change outweighed non-climate change factors.
Similar changes emerge in coastal and marine ecosystems with shifting distributions of economically and ecologically important species attributed to climate change. While fishing mortality has historically been the principal driver of variation in ecological goods derived from the sea in support of coastal communities, climate change impacts now exceed such effects (Blanchard et al. 2024; Hare et al. 2012; Rooper et al. 2020).
To improve the draft BCCA to better incorporate detection and attribution, one approach would be to divide observed biodiversity changes between the BCCA Chapters 3 and 4, with changes detected and attributed to anthropogenic climate change in Chapter 3 and changes primarily due to non-climate change factors in Chapter 4.
Treatment of Uncertainty
As noted earlier in this chapter, the BCCA will be most useful if it establishes a standardized approach to evaluating and communicating uncertainty. Communication of uncertainty requires consistent terms throughout the assessment to characterize confidence and likelihood. Although the draft of the BCCA that the Committee reviewed had not yet reached the stage of development, in most chapters, to include findings and recommendations, the BCCA draft contains text relevant to treatment of uncertainty and the Committee offers guidance on that text in this section.
Evaluation of uncertainty in primary literature for an assessment can be complex. The draft BCCA would be improved with greater attention to this characterization, to ensure that the information is conveyed in a way that does not create misconceptions. The assessment considers a variety of scales at which an impact or phenomena is characterized and these differences in scales may affect how uncertainty is viewed and the robustness of understanding around a given topic. When bringing literature into an assessment, it is important to ensure that reported uncertainty that may be associated with a specific scale or context does not create misconceptions about the strength of a large pool of evidence or degree of uncertainty about a more general concept. Additionally, framing of discussions of uncertainty should be done in a way that can be useful for resource management or policy decisions and account for other factors that may be influencing observed climate and biodiversity interactions. Discussion of non-linear responses to stressors in the context of uncertainty is also valuable, for example, regime shifts in ecosystems triggered by climate change or other stressors (Xu et al. 2023).
Finally, careful consideration should be given to information that demonstrates “evidence of absence” of an effect versus “absence of evidence.” Studies that show no effect of climate on biodiversity, for instance, are different than a lack of information to indicate an effect may exist. Further, while studies on particular attributes of biodiversity and climate may not be geographically comprehensive, addressing what is known, even with conflicting results, can inform elements of uncertainty.
Conclusion 2.8: A scientifically robust biodiversity and climate change assessment robustly assesses published research, Indigenous Knowledge, and Local Ecological Knowledge for detection of changes and attribution of changes to anthropogenic climate change (as opposed to non-climate change factors), as well as evaluates and conveys associated uncertainties in terms appropriate for the intended audience.
WEAVING TOGETHER MULTIPLE WAYS OF KNOWING
Bringing together available Indigenous Knowledge, Local Ecological Knowledge, and Western science introduces opportunities for a more holistic understanding of biodiversity and climate change than could be achieved by Western science alone (such as observed in frameworks of IPBES 2024; Reid et al. 2021; STACC 2025; STACC 2021; Varghese and Crawford 2021). Such frameworks amplify the work of Indigenous Peoples, Nations, and communities while highlighting the vital importance of multiple Knowledges in climate science and how their values, voices, kinship relationships, and culture are essential for understanding how long-standing practices of Indigenous Peoples demonstrate/ensure sustainability and can be models for stewardship/management today.
Local Ecological Knowledge among any groups living in a place can provide a more holistic perspective and knowledge that improves understanding of biodiversity and climate relationships and changes. The draft
BCCA has taken positive steps in striving to weave in Indigenous Knowledge, Indigenous sovereignty rights, and Indigenous-related policy issues into some draft chapters (e.g., draft BCCA Chapters 1, 4, and 2.a), but this synthesis is inconsistent and included to a lesser extent across other chapters of the draft assessment.
Acknowledgement of History
Providing a brief history of the relationship between Indigenous Peoples and biodiversity provides useful context for how biodiversity has changed over time. Biodiversity in North America has historically been influenced by non-human forces followed by influences from human forces, such as through the co-evolution with Indigenous Peoples and their stewardship practices. Indigenous Peoples’ presence in the Americas goes back at least 25,000 years BCE. While that is relatively recent, in areas that were glaciated, that amounts to the same span of time during which floral and faunal communities were co-evolving. Today, advances in science (e.g., palynological data) have found that Indigenous Peoples had a mostly beneficial impact on biodiversity and have awareness of processes that interact with them, such as fire, flooding, and harvest of other species in the marine environment.
Biodiversity in North America has been negatively affected by settler colonialism: biodiversity co-evolved with Indigenous Peoples and their stewardship practices. When Indigenous Peoples and their stewardship practices were then removed and replaced by other practices, biodiversity was lost. The climate system has also undergone extensive and rapid change due to human activities since the industrial revolution. Providing this history in biodiversity and climate change assessments acknowledges the role of human activities in affecting biodiversity and climate change while also introducing the importance of amplifying Indigenous Knowledge and Local Ecological Knowledge in assessments. Including discussion of Indigenous sovereignty is also important for amplifying and weaving Indigenous Knowledge into assessments. In Canada and the U.S., Indigenous sovereignty predates colonization. In Mexico, Indigenous Peoples’ history is much older and more complex, and there are not sovereign nations today in the way there are in Canada and the U.S. Indigenous Knowledge focused on the protection of biodiversity and agrobiodiversity and its significance for the management of natural resources in Mexico (and Mesoamerica more broadly) is detailed in a synthesis by Boege (2008).
Discussion of Current Structures
Discussing existing structures that may influence how Indigenous Knowledge is emphasized in understanding of biodiversity and climate change provides important context for assessments. For example, policies recognizing sovereignty rights are rapidly evolving, with differences among Canada, the U.S., and Mexico. Existing policies in these nations give Indigenous Peoples sovereignty rights but do not recognize rivers, forests, other landscapes, or wildlife as having rights as living entities (Parotta and Agnoletti 2012; Trosper et al. 2012), as is the case in some other locations such as New Zealand. The draft BCCA would benefit from being explicit in explaining that this is occurring and providing discussion of Indigenous data sovereignty, in addition to sovereign lands.
Acknowledgement of different relationships between Indigenous Peoples and national governments would also be valuable in the BCCA. The Government of Canada has shown a commitment to achieving reconciliation with Indigenous Peoples through renewed, nation-to-nation, government-to-government, and Inuit-Crown relationships based on recognition of rights, respect, cooperation, and partnership as the foundation for transformative change. Indigenous Peoples have a special constitutional relationship with the Crown. This relationship, including existing Aboriginal and treaty rights, is recognized and affirmed in section 35 of the Constitution Act, 1982. Section 35 contains a full box of rights and holds the promise that Indigenous nations will become part-
ners in Confederation on the basis of a fair and just reconciliation between Indigenous peoples and the Crown. In the U.S., there are non-federally recognized tribes that also have knowledge important to understanding biodiversity and climate change. In Mexico, after a unanimous approval by the Congress, in September 2024 a reform of Article 2 of the National Constitution entered into force whereby Indigenous Peoples were granted a broad array of specifically recognized rights.
Adoption of Consistent and Current Terminology
The BCCA (and any assessment) is most appropriate when consistent terminology referencing Indigenous Knowledge and associated terms is used. This includes defining the terms and ensuring that terms reflect the most recent accepted language—terminology is evolving rapidly. “Indigenous Knowledge” is currently the appropriate term to use and is widely accepted, including by the U.S. and Canadian federal governments. Authors should adopt this throughout the draft assessment. In the draft BCCA, “traditional knowledge”, “traditional ecological knowledge” and, in the Indigenous context, “local knowledge” are also currently included. Indigenous Knowledge brings together shared values, but Indigenous nations and communities are also unique and different from one another and bring different types of knowledge and perspectives. Assessments should include a well-cited definition that considers federal and internationally recognized definitions (such as those provided earlier in this chapter of the Committee’s report) and links between the federal policy definitions and strategic actions to be taken supported by those definitions (e.g., Tribal partnerships and data sovereignty), while also being accessible to the intended audience(s). In the context of this assessment and relevant federal documents, “stewardship” is a preferred term for Indigenous Peoples’ traditional practices which encompasses taking care with reciprocity. Terms like “integration” should not be used given they hold negative segregation connotations related to assimilation.
Conclusion 2.9: Synthesizing Indigenous Knowledge, Local Ecological Knowledge, and Western science when assessing linkages between biodiversity and climate change creates a synergistic, deeper understanding of historical relationships at multiple scales (local to landscape) underlying current status and trends and provides a more holistic perspective to inform strategic management and policy options.
CONNECTING BIODIVERSITY AND CLIMATE CHANGE TO SOCIETY
A key element of the study and assessment of biodiversity and climate change is the connection to people. All humans benefit from nature, and healthy, diverse ecosystems underpin healthy, productive communities. Healthy, biodiverse ecosystems and stable climates support food production, protect watersheds, filter pollutants in the air and water, and provide spiritual value among many other benefits (IPBES 2018b).
In contrast, degraded ecosystems and climate-driven environmental hazards can disrupt societies and have detrimental impacts on communities. These impacts and their magnitudes are not equally distributed across communities. Marginalized communities including Indigenous communities; communities of color; urban, remote, and rural populations; and natural resource dependent communities can all be disproportionately impacted by biodiversity loss and climate change. Productive, economic processes directly linked to natural resources are the most affected. These impacts can intersect with varying levels of decision-making authority where those developing policies related to biodiversity and climate change may not be the ones that benefit or are harmed by the outcomes of those policies. For example, U.S. policies for land allotment have included the location of Indigenous Peoples, which may limit their ability to adapt and respond to environmental changes (Marino et al. 2023 and citations therein).
The draft BCCA would be improved by a stronger emphasis explaining the societal benefits from, specifically, the linking of biodiversity and climate and conveying it in meaningful language for the intended audience. Environmental justice and equity issues are addressed in some sections of the draft BCCA. More systematic analysis and treatment of these topics, focused on links to biodiversity and climate change, across all chapters would strengthen the assessment, including both the science and policy chapters.
Conclusion 2.10: Biodiversity and climate interactions are fundamental to supporting human wellbeing (clean air, clean water, agriculture, forestry, fisheries, mental health, etc.). The Biodiversity and Climate Change Assessment would be strengthened by more explicit evaluation of the implications for well-being across different segments of society and communication of the importance to society in language accessible to the intended audience(s).
LINKING SCIENCE TO MANAGEMENT AND POLICY
Assessments that synthesize the science and existing policies for the region of study and highlight key issues can serve as a reference for a wide range of audiences and foster greater understanding of the role of management and policy in shaping the future for biodiversity and climate. Further, these assessments can inform decisions about how to manage ecosystems and create policies that critically examine trade-offs and benefits for biodiversity and/or climate as well as highlight key funding mechanisms and institutions. Bringing together the science and policy aspects of biodiversity and climate change across three countries and many Indigenous communities, as the draft BCCA has done, also provides an opportunity to compare and contrast national-scale approaches and learn from one another.
The draft BCCA discusses natural resource management and policy largely through two overarching chapters that are divided into subsections1 for Canada, the U.S., Mexico, and transboundary issues. Although not explicitly stated, it appears that the draft BCCA generally uses Chapter 2 to detail historical and existing laws and policies relevant to biodiversity and climate change for each country and Chapter 8 focuses on future policy options and solutions. This section of the Committee’s review provides guidance for both content and structure for the BCCA, with broader relevance to any multi-national assessments intended to link science to decision-making.
Bridging Policy Scales and Boundaries
Assessments of biodiversity and climate change that examine management and policy can provide useful information to incorporate climate change into national and sub-national biodiversity conservation policy. The primary focus of the BCCA is at the regional to national scale, however sub-national jurisdictions (e.g., states, provinces, territories) exert a strong force on biodiversity conservation (e.g., regulation of local land use such as timber harvesting and legal power over environmental issues such as air and water pollution). While the assessment cannot consider every policy at all scales, policy analysis at the sub-national scale, in addition to nationally, could enhance the usefulness of the assessment. Furthermore, locally specific natural resource management information on biodiversity and climate change can inform effective conservation in national parks, other protected areas, and private lands and waters under climate change (e.g., Gonzalez et al. 2018; Griffith et al. 2009; Millar and Stephenson 2015; Sweet at al. 2019).
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1 In the draft BCCA, subsections are referred to as “chapters” designated with a number (2 or 8) and a letter (a-d). The same naming approach is used in this report when comments are directed to a specific national subsection.
The draft BCCA includes some discussion of smaller scales in example boxes, which could be elevated into the main text for greater effectiveness. Description of partnerships at these smaller scales could also be effective to highlight in the BCCA for framing and demonstrating positive outcomes for biodiversity and climate. For example, Sage Grouse Grassland conservation efforts have brought together the federal government and multiple U.S. states to develop policies across jurisdictional boundaries. Restoration of the Skutik River has included federal Canadian and U.S. governments, the province of New Brunswick, state of Maine, and Indigenous communities with a goal to restore the river ecosystem and support the return of alewife and river herring.
The impact of an assessment detailing policies within multiple nations and across national boundaries is stronger when the materials are clearly linked among national sections and presented in a consistent manner that allows for comparisons. This consistency demonstrates a synthesis of materials and ideas and can allow for emergence of unique key messages. Further, it helps to inform how to approach future policies and identify solutions at national and transboundary scales. The draft BCCA would be improved with the adoption of a consistent approach and organizational style for content included in Chapters 2 and 8 (both within and across chapters). Currently, it is difficult to link these sections to one another. Enhanced engagement by the author teams leading each of these sections could help to improve cohesion. A clear description of the selected approach, goals for the individual sections, and explanation for how the sections are intended to be used would benefit readers.
Transboundary governance in a North American assessment is a key component to advancing understanding of changes in biodiversity and climate and developing management and policy solutions to improve future outcomes. The draft BCCA includes reference to the Great Lakes, which is effective and important example to highlight, but additional examples for both the Canada-U.S. and U.S.-Mexico borders would strengthen the assessment. Discussion of this topic should draw on historical trilateral and bilateral agreements that have had significant effects. For example, Waterton Lakes National Park (Canada) and Glacier National Park (U.S.) oversee contiguous federal lands together as a biosphere reserve. During wildlife situations, such as fires (e.g., the Kenow Wildfire in 2017), the two parks pool their resources and coordinate responses.
For a North American assessment, it would also be valuable to explore the differences between the Canada-U.S. border and the U.S.-Mexico border. Canada and the U.S., in collaboration with other partners including Indigenous communities, have demonstrated a strong partnership in ecosystem restoration and management that has benefitted bison, grizzly bears, lynx, and wolverines. Coordination across the U.S.-Mexico border is much more fragmented, but there are examples (e.g., the California Condor) and those should also be brought into the assessment. In Mexico, the lack of federal recognition of Indigenous communities until very recently has influenced community engagement in transboundary efforts along this border. A compare and contrast of which Indigenous People have rights and decision-making power in each country could be considered.
Organization of Policy Discussions
Bringing together national and transboundary policy materials is complex but can be effective when organized in ways that help navigate readers through the material and appropriately connect issues across sections.
Historical and future policy decisions are inherently linked to one another and the draft BCCA would be strengthened if it more clearly linked the similar themes in Chapter 2 and Chapter 8. To be most effective, BCCA Chapter 8 would follow from and build upon ideas put forth in Chapter 2, thus moving from a description of existing policies to a discourse on future directions for policy. An assessment of this kind could also consider a different overarching framework in policy chapters (that aligns with the broader assessment framework) focused, for instance, around themes (e.g., terrestrial, freshwater, marine, endangered species) to share a more synthetic description of past and future efforts.
Greater consistency in the level of detail provided for each nation in Chapters 2 and 8 is also important, with inclusion only of the most relevant materials. In the draft BCCA, there is considerable variation in the detail and lengths of the national sections. This could be misinterpreted to indicate that section lengths reflect the number of policies or amount of activity around biodiversity and climate change when it may instead be the result of different BCCA chapter authoring groups using different approaches to select their chapter’s content.
As with other parts of the BCCA and assessments more generally, it is important for policy chapters to include key summary figures that provide overarching context and findings, developed with the intended audience(s) in mind, to assist readers in orienting to the materials and main messages.
Conclusion 2.11: The Biodiversity and Climate Change Assessment has a distinct opportunity to compare biodiversity and climate change resource management approaches and policies across countries and to connect current and future policy options. Adopting greater consistency across Chapters 2 and 8 would help to foster this type of analysis.
