Portal de Periódicos da CAPES

Establishing IUCN Red List Criteria for Threatened Ecosystems

2010; Wiley; Volume: 25; Issue: 1 Linguagem: Inglês

10.1111/j.1523-1739.2010.01598.x

1523-1739

Jon Paul Rodrı́guez, Kathryn M. Rodríguez‐Clark, Jonathan Baillie, Neville Ash, John Benson, Timothy M. Boucher, Claire Brown, Neil D. Burgess, Ben Collen, Michael D. Jennings, David A. Keith, Emily Nicholson, Carmen Revenga, Belinda Reyers, Mathieu Rouget, Tammy Smith, Mark Spalding, Andrew Taber, Matt Walpole, Irene Zager, Tara Zamin,

Land Use and Ecosystem Services

Abstract: The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature's (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem's extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012. Resumen: El potencial para la conservación de muchas especies ha avanzado enormemente porque la Unión Internacional para la Conservación de la Naturaleza (UICN) ha desarrollado criterios objetivos, repetibles y transparentes para evaluar el riesgo de extinción que explícitamente separa la evaluación de riesgo de la definición de prioridades. En el IV Congreso Mundial de Conservación en 2008, el proceso comenzó a desarrollar e implementar estándares globales comparables para ecosistemas. Un grupo de trabajo establecido por la UICN ha formulado un sistema inicial de categorías y criterios cuantitativos, análogos a los utilizados para especies, para asignar niveles de amenaza a ecosistemas a niveles local, regional y global. Un sistema final requerirá de definiciones de ecosistemas; cuantificación del estatus de ecosistemas; identificación de las etapas de degradación y pérdida de los ecosistemas; medidas de riesgo (criterios) alternativas; umbrales de clasificación para esos criterios y métodos estandarizados para la realización de evaluaciones. El sistema deberá reflejar el nivel y tasa de cambio en la extensión, composición, estructura y funcionamiento de un ecosistema, y tener sus raíces conceptuales en la teoría ecológica y la investigación empírica. Sobre la base de esos requerimientos y la hipótesis de que el riesgo del ecosistema es una función del riesgo de las especies que lo componen, proponemos un conjunto de 4 criterios: declinaciones recientes en la distribución o funcionamiento ecológica, pérdida total histórica en la distribución o funcionamiento ecológico, distribución pequeña combinada con declinación, o distribución muy pequeña. La mayor parte del trabajo se ha concentrado en ecosistemas terrestres, pero también se requieren umbrales y criterios comparables para ecosistemas dulceacuícolas y marinos. Estos son los primeros pasos de un proceso de consulta internacional que llevará a una propuesta unificada que será presentada en el próximo Congreso Mundial de Conservación en 2012. In the last 50 years, humans have altered the world's ecosystems more than during any other time span in history. Twenty to seventy percent of the area of 11 of the 13 terrestrial biomes evaluated in the Millennium Ecosystem Assessment (2005a) has been converted to human use. Although informed and effective policy may slow land conversion (Watson 2005), there is no consistent, widely accepted scientific framework for tracking the status of Earth's ecosystems and identifying those with a high probability of loss or degradation (Nicholson et al. 2009). Recognizing this gap, the fourth IUCN (International Union for Conservation of Nature) World Conservation Congress launched a process to develop criteria for assessing the status of and establishing a global red list of ecosystems (IV World Conservation Congress 2008). We use the term ecosystem as an assemblage of organisms that occur together in space and time and interact with each other and their physical environment (Odum 1971). The IUCN uses quantitative and qualitative criteria to classify species by their probability of extinction (i.e., extinction risk) and to guide policy and interventions at all levels (IUCN 2010a). Furthermore, the IUCN's criteria are the basis for some of the Convention on Biological Diversity's indicators (CBD 2003, 2010) and indices of biological diversity (Butchart et al. 2004, 2007), which are being used to track progress toward international conservation targets (Millennium Development Goals 2009; Walpole et al. 2009). At national scales, species red lists inform policy and action in more than 100 countries and provide ample data for other conservation applications (IUCN 2010a; Zamin et al. 2010). Ecosystem red lists have the potential to complement the policy successes of species red lists in several ways. Ecosystems may more effectively represent biological diversity as a whole than do individual species (Noss 1996; Cowling et al. 2004), especially given the taxonomic bias of the current IUCN Red List (Vié et al. 2009; Stuart et al. 2010). Moreover, they include fundamental abiotic components that are only indirectly included in species assessments (e.g., riverine ecosystems; Beechie et al. 2010). Declines in ecosystem status may also be more apparent than extirpations or extinctions of individual species; society often perceives loss of biological diversity in terms of loss of benefits such as clean water, food, timber, and fuel (Millennium Ecosystem Assessment 2005a). Ecosystem-level assessments may also be less time consuming than species-by-species assessments. Despite concerted efforts, by 2010 the status of only 47,978 of the world's 1,740,330 known species ( 80%) and the threatening process was ongoing or expected to commence in the near term (Table 1). Lower risk levels, such as "endangered," could be assigned if the decline in function was equally severe, but the extent was less. By presenting preliminary, relatively simple criteria and thresholds (Table 1; Fig. 1), we do not imply that arriving at a final, unified system for assessment of ecosystem risk will be easy; in addition to the conceptual challenges, there are methodological and logistical issues to confront. For example, what is the best method for measuring the geographical distribution of an ecosystem? Or, how does one precisely define a location? The IUCN produces periodically updated, detailed guidelines for addressing these methodological questions in reference to species (IUCN 2010b). We expect that the development of analogous guidelines for ecosystems will be a major component of the consultation process that will take place over the next few years. Nearly 15 years passed between the initial development of criteria for the IUCN Red List of Threatened Species and their official adoption (Mace et al. 2008). To minimize delay in the adoption of such criteria for ecosystems, it will be crucial to formulate a unified proposal for criteria and thresholds and make this proposal available online in scientific and popular venues. Protocols will need to be tested in a broad set of institutional contexts, geographical regions, and ecosystem types, and the protocols will need to be useful at local and global scales. The institutional capacity of IUCN and other participating organizations will need strengthening to implement such a global assessment of ecosystem risk. It is important to differentiate ecosystem risk assessment—a scientific, technical activity—from priority setting, a fundamentally societal, value-laden activity (Possingham et al. 2002; Lamoreux et al. 2003; Miller et al. 2006; Mace et al. 2008). As species red lists have demonstrated, transparent, objective, and scientifically based assessments are prerequisites for sound policy and planning (Mace et al. 2008). To ensure the scientifically credible application of criteria in red listing of ecosystems, case studies are needed to show how risk assessments can inform priority-setting efforts. Although the scientific and logistical challenges to developing criteria for an ecosystem red list are substantial, we believe the time is right to do so. Current opportunities include ongoing assessments at local and global scales, a strong IUCN mandate from governments and the conservation community, public concern worldwide about ecosystems and human dependence on them, a rich experience with the species red-listing process, and continuing and massive improvements in data collection and computing power. What remains is to engage the world's conservation and ecosystem scientists in this task. We are grateful to R. Akçakaya, E. Fleishman, S. Gergel, and anonymous reviewers for their constructive comments on previous versions of this paper. V. Abreu, P. Comer, J. de Queiroz, D. Faber-Langendoen, D. Grossman, C. Josse, A. Lindgaard, and R. Sayre provided excellent feedback during a workshop held at NatureServe headquartes. J.P.R. and I.Z. acknowledge the support of Fondo Nacional de Ciencia, Tecnología e Innovación (Agenda Biodiversidad, Segunda Fase, no. 200001516). B.R., T.S., and M.R. are grateful for the support of the Council for Scientific and Industrial Research and the South African National Biodiversity Institute. Funding for attendance at workshops and other general activities of the working group was provided by the Commission on Ecosystem Management of IUCN, and the UICN Sur office in Quito, Ecuador. Funding for assuring open-access of this article was provided by Instituto Venezolano de Investigaciones Científicas. Translations were kindly provided by Elodie Chene (French), Sekar Palupi (Bahasa Indonesian), Anne-Mette Høeg Andersen (Danish), and Keping Ma and Chun Minli (Chinese). Provita is a local conservation partner of the Ecohealh Alliance, formerly known as Wildlife Trust. Appendix S1 Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.