RESUMEN
Protected area management often depends heavily on law enforcement to secure compliance with rules. However, this can contribute to conflict between protected area authorities and local people, negatively affecting both human well-being and conservation outcomes. Compliance is affected by many factors, including whether those who enforce rules are perceived to do so fairly, as well as the perceived rule-related behavior of others. We used factorial survey experiments to explore how fair respondents living around protected areas in Indonesia and Tanzania perceive sanctions distributed by law enforcers to be. We presented scenarios to respondents to assess how crime type, offender characteristics, and corruption influenced their judgments regarding the fairness of administered sanctions. We also assessed how descriptive norms and corruption influenced individuals' willingness to obey protected area rules. Data were collected from 229 people in Indonesia and 217 in Tanzania. Results showed that in both locations, lawful sanctions, such as arrests or warnings, were perceived as fairer, and sanctions that involved corruption were perceived as least fair. Attitudes toward protected area rules, corruption, and descriptive norms all influenced people's willingness to comply, whereas multidimensional poverty did not. Our results highlight the need for conservation policy and practice to move beyond narratives that focus on the need for more law enforcement. To improve protected area compliance and secure better outcomes for people and nature, conservation must focus on ensuring the fair administration of rules and enhancing the legitimacy of rules themselves.
Mejoras en el cumplimiento alrededor de las áreas protegidas mediante la administración imparcial de reglas Resumen El manejo de áreas protegidas casi siempre depende de la aplicación de la ley para asegurar el cumplimiento de las reglas. Sin embargo, esto puede contribuir al conflicto entro las autoridades de las áreas protegidas y los locales, lo que afecta negativamente al bienestar humano y a los resultados de conservación. El cumplimiento se ve afectado por muchos factores, incluido si se percibe que quienes aplican las reglas lo hacen de manera imparcial, así como el comportamiento relacionado a las reglas de las demás. Aplicamos experimentos de censo factorial para explorar cómo los respondientes imparciales que viven en torno a las áreas protegidas en Indonesia y Tanzania perciben las sanciones distribuidas por los agentes de la ley. Les presentamos escenarios para analizar cómo el tipo de crimen, características del ofensor y la corrupción influyen sobre sus juicios con respecto a la imparcialidad de las sanciones administradas. También analizamos cómo las normas descriptivas y la corrupción influyen sobre la voluntad individual de obedecer las reglas del área protegida. Recolectamos los datos de 299 personas en Indonesia y 217 en Tanzania. Los resultados mostraron que, en ambas localidades, las sanciones legales, como arrestos o advertencias, eran percibidas como más justas, y las sanciones que involucraban corrupción eran percibidas como las menos justas. Todas las actitudes hacia las reglas de las áreas protegidas, la corrupción y las normas descriptivas influyeron sobre la voluntad de las personas para obedecer, mientras que la pobreza multidimensional no influyó. Nuestros resultados enfatizan la necesidad de que las políticas y prácticas de conservación vayan más allá de las narrativas que se enfocan en la necesidad de una mayor aplicación de la ley. Para incrementar el cumplimiento en las áreas protegidas y asegurar mejores resultados para las personas y la naturaleza, la conservación debe enfocarse en garantizar la administración imparcial de las reglas e incrementar su legitimidad.
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Millions of households globally rely on uncultivated ecosystems for their livelihoods. However, much of the understanding about the broader contribution of uncultivated ecosystems to human wellbeing is still based on a series of small-scale studies due to limited availability of large-scale datasets. We pooled together 11 comparable datasets comprising 232 settlements and 10,971 households in ten low-and middle-income countries, representing forest, savanna and coastal ecosystems to analyse how uncultivated nature contributes to multi-dimensional wellbeing and how benefits from nature are distributed between households. The resulting dataset integrates secondary data on rural livelihoods, multidimensional human wellbeing, household demographics, resource tenure and social-ecological context, primarily drawing on nine existing household surveys and their associated contextual information together with selected variables, such as travel time to cities, population density, local area GDP and land use and land cover from existing global datasets. This integrated dataset has been archived with ReShare (UK Data Service) and will be useful for further analyses on nature-wellbeing relationships on its own or in combination with similar datasets.
Asunto(s)
Ecosistema , Pobreza , Desarrollo Sostenible , Humanos , Composición Familiar , Población RuralRESUMEN
Analysis reveals emission reductions from forest conservation have been overestimated.
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Carbono , Cambio Climático , Conservación de los Recursos Naturales , BosquesRESUMEN
Conservationists increasingly aim to understand human behaviour to inform intervention design. However, obtaining information from people about their behaviour can be challenging, particularly if the research topic is considered sensitive. Topic sensitivity may raise methodological, ethical, political and legal concerns which, if poorly addressed, can have significant impacts on research participants, the research process, data quality and the success of conservation outcomes that are informed by research findings. While considerable effort has been invested in developing techniques for reducing bias when collecting data on sensitive topics, less attention has been focused on identifying if, and why, a topic is sensitive.We use a mixed methods approach to explore how willing people are to discuss topics that could be considered sensitive (e.g. illegal wildlife hunting). Collecting data from people living near protected areas in Indonesia (n = 362) and Tanzania (n = 345), we developed and tested a psychometric scale to measure topic sensitivity at the respondent level and conducted group exercises (free-lists and pile sorts) to gain a deeper understanding of peoples' willingness to discuss different topics.The perceived sensitivity of topics varied both within and between the two focal contexts, with more topics being perceived as sensitive in Tanzania than Indonesia. Participants' knowledge of rules, and their experiences of living alongside protected areas affected how sensitive they considered topics to be.Mixed methods approaches can provide holistic and nuanced understanding of topic sensitivity. However, recognising that in-depth studies are not always feasible to implement, we demonstrate that methods, such as our Sensitivity Index, can easily be adapted for different contexts and deployed to rapidly obtain valuable insights on topic sensitivity, to help inform conservation research and practice.
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To develop more effective interventions, conservationists require robust information about the proportion of people who break conservation rules (such as those relating to protected species, or protected area legislation). Developed to obtain more accurate estimates of sensitive behaviors, including rule-breaking, specialized questioning techniques such as Randomized Response Techniques (RRTs) are increasingly applied in conservation, but with mixed evidence of their effectiveness. We use a forced-response RRT to estimate the prevalence of five rule-breaking behaviors in communities living around the Ruaha-Rungwa ecosystem in Tanzania. Prevalence estimates obtained for all behaviors were negative or did not differ significantly from zero, suggesting the RRT did not work as expected and that respondents felt inadequately protected. To investigate, we carried out a second study to explore how topic sensitivity influenced respondents' propensity to follow RRT instructions. Results from this experimental study revealed respondents understood instructions well (~88% of responses were correct) but that propensity to follow RRT instructions was significantly influenced by the behavior asked about, and the type of answer they were required to provide. Our two studies highlight that even if RRTs are well understood by respondents, where topics are sensitive and respondents are wary of researchers, their use does not necessarily encourage more honest responding.
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Biodiversity offsetting is a globally influential policy mechanism for reconciling trade-offs between development and biodiversity loss. However, there is little robust evidence of its effectiveness. We evaluated the outcomes of a jurisdictional offsetting policy (Victoria, Australia). Offsets under Victoria's Native Vegetation Framework (2002-2013) aimed to prevent loss and degradation of remnant vegetation, and generate gains in vegetation extent and quality. We categorised offsets into those with near-complete baseline woody vegetation cover ("avoided loss", 2702 ha) and with incomplete cover ("regeneration", 501 ha), and evaluated impacts on woody vegetation extent from 2008 to 2018. We used two approaches to estimate the counterfactual. First, we used statistical matching on biophysical covariates: a common approach in conservation impact evaluation, but which risks ignoring potentially important psychosocial confounders. Second, we compared changes in offsets with changes in sites that were not offsets for the study duration but were later enrolled as offsets, to partially account for self-selection bias (where landholders enrolling land may have shared characteristics affecting how they manage land). Matching on biophysical covariates, we estimated that regeneration offsets increased woody vegetation extent by 1.9%-3.6%/year more than non-offset sites (138-180 ha from 2008 to 2018) but this effect weakened with the second approach (0.3%-1.9%/year more than non-offset sites; 19-97 ha from 2008 to 2018) and disappeared when a single outlier land parcel was removed. Neither approach detected any impact of avoided loss offsets. We cannot conclusively demonstrate whether the policy goal of 'net gain' (NG) was achieved because of data limitations. However, given our evidence that the majority of increases in woody vegetation extent were not additional (would have happened without the scheme), a NG outcome seems unlikely. The results highlight the importance of considering self-selection bias in the design and evaluation of regulatory biodiversity offsetting policy, and the challenges of conducting robust impact evaluations of jurisdictional biodiversity offsetting policies.
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Biodiversidad , Conservación de los Recursos Naturales , Conservación de los Recursos Naturales/métodos , Madera , Motivación , Victoria , EcosistemaRESUMEN
Although some sectors have made significant progress in learning from failure, there is currently limited consensus on how a similar transition could best be achieved in conservation and what is required to facilitate this. One of the key enabling conditions for other sectors is a widely accepted and standardized classification system for identifying and analyzing root causes of failure. We devised a comprehensive taxonomy of root causes of failure affecting conservation projects. To develop this, we solicited examples of real-life conservation efforts that were deemed to have failed in some way, identified their underlying root causes of failure, and used these to develop a generic, 3-tier taxonomy of the ways in which projects fail, at the top of which are 6 overarching cause categories that are further divided into midlevel cause categories and specific root causes. We tested the taxonomy by asking conservation practitioners to use it to classify the causes of failure for conservation efforts they had been involved in. No significant gaps or redundancies were identified during this testing phase. We then analyzed the frequency that particular root causes were encountered by projects within this test sample, which suggested that some root causes were more likely to be encountered than others and that a small number of root causes were more likely to be encountered by projects implementing particular types of conservation action. Our taxonomy could be used to improve identification, analysis, and subsequent learning from failed conservation efforts, address some of the barriers that currently limit the ability of conservation practitioners to learn from failure, and contribute to establishing an effective culture of learning from failure within conservation.
Introducción de una taxonomía común como apoyo al aprendizaje a partir del fracaso en la conservación Resumen Mientras que algunos sectores han progresado significativamente en el aprendizaje a partir del fracaso, actualmente hay un consenso limitado sobre cómo podría lograrse una transición similar en la conservación y qué se requiere para facilitarla. Una de las condiciones habilitantes más importantes en otros sectores es un sistema de clasificación estandarizado y aceptado por la mayoría para la identificación y análisis de las causas fundamentales del fracaso. Diseñamos una taxonomía completa de las causas fundamentales del fracaso que afecta a los proyectos de conservación. Para desarrollarla, solicitamos ejemplos de esfuerzos de conservación reales que de alguna manera se consideraron como fracasos, identificamos las causas fundamentales no aparentes de su fracaso y luego las usamos para desarrollar una taxonomía genérica de tres niveles de las maneras en las que fracasan los proyectos, en cuyo nivel superior están seis categorías de causas generales que después se dividen en categorías de nivel medio de categorías de causas y causas fundamentales específicas. Pusimos a prueba la taxonomía al pedirle a los practicantes de la conservación que la usaran para clasificar las causas del fracaso de los esfuerzos de conservación en los que han participado. No identificamos vacíos o redundancias importantes durante esta fase de prueba. Después, analizamos la frecuencia con la que los proyectos de esta muestra se enfrentaron a causas fundamentales particulares, lo que sugirió que algunas causas fundamentales tienen mayor probabilidad de ocurrir y que un número reducido de causas fundamentales tiene mayor probabilidad de ocurrir en proyectos que implementan ciertos tipos de acciones de conservación. Nuestra taxonomía podría usarse para mejorar el análisis, identificación y aprendizaje subsecuente a partir del fracaso de los esfuerzos de conservación; tratar algunas de las barreras que en la actualidad limitan a los practicantes de la conservación a aprender del fracaso; y contribuir al establecimiento de una cultura efectiva del aprendizaje a partir del fracaso dentro de la conservación.
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Conservación de los Recursos Naturales , Terminología como AsuntoRESUMEN
Reducing emissions from deforestation and forest degradation (REDD+) projects aim to contribute to climate change mitigation by protecting and enhancing carbon stocks in tropical forests, but there have been no systematic global evaluations of their impact. We used a new data set for tropical humid forests and a standardized evaluation approach (based on pixel matching) to quantify the performance of a representative sample of 40 voluntary REDD+ projects in 9 countries certified under the Verified Carbon Standard (VCS). In the first 5 years of implementation, deforestation within project areas was reduced by 47% (95% confidence interval [CI]: 24-68) compared with matched counterfactual pixels, and degradation rates were 58% lower (95% CI: 49-63). Reductions were small in absolute terms but greater in sites located in high-deforestation settings and did not appear to be substantially undermined by leakage activities in forested areas within 10 km of project boundaries. At the 26th Conference of the Parties of the United Nations Framework Convention on Climate Change, the international community renewed its commitment to tackling tropical deforestation as a nature-based solution to climate change. Our results indicate that incentivizing forest conservation through voluntary site-based projects can slow tropical deforestation and highlight the particular importance of prioritizing financing for areas at greater risk of deforestation.
Evaluación Global de la Efectividad de proyectos REDD+ en la Reducción de la Deforestación y Degradación en el Trópico Húmedo Resumen Los proyectos para la reducción de emisiones derivados de la deforestación y degradación de bosques (REDD+) tienen como meta contribuir a la mitigación del cambio climático al protejer y fomentar la disponibilidad de carbono en bosques tropicales, pero a la fecha no se han realizado evaluaciones globales sistemáticas sobre su impacto. Utilizamos bases de datos recientes sobre bosques tropicales húmedos y un método estandarizado de evaluación (basado en 'emparejamiento' [matching] de pixeles) para cuantificar el desempeño de una muestra representativa de 40 proyectos voluntarios REDD+ , localizados en 9 países y certificados bajo el estándar Verified Carbon Standard (VCS). En los primeros 5 años de implementación, la deforestación en las áreas de los proyectos disminuyó en 47% (IC 95% 24-68) en comparación con los pixeles contrafactuales correspondientes, y las tasas de degradación fueron 58% menos (IC 95% 49-63). Las reducciones fueron pequeñas en términos absolutos pero mayores en sitios con tasas de deforestación elevadas, y no parecieron ser afectadas sustancialmente por efectos de fuga (leakage) en áreas boscosas en un radio de 10 km de los límites del proyecto. En la COP26, la comunidad internacional renovó su compromiso de afrontar la deforestación tropical como una solución al cambio climático basada en la naturaleza. Nuestros resultados indican que incentivar la conservación de bosques mediante proyectos locales voluntarios puede disminuir la deforestación tropical, y resaltan la importancia de priorizar financiamiento en áreas con un mayor riesgo de deforestación.
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Conservación de los Recursos Naturales , Bosques , Cambio Climático , CarbonoRESUMEN
International policy is focused on increasing the proportion of the Earth's surface that is protected for nature1,2. Although studies show that protected areas prevent habitat loss3-6, there is a lack of evidence for their effect on species' populations: existing studies are at local scale or use simple designs that lack appropriate controls7-13. Here we explore how 1,506 protected areas have affected the trajectories of 27,055 waterbird populations across the globe using a robust before-after control-intervention study design, which compares protected and unprotected populations in the years before and after protection. We show that the simpler study designs typically used to assess protected area effectiveness (before-after or control-intervention) incorrectly estimate effects for 37-50% of populations-for instance misclassifying positively impacted populations as negatively impacted, and vice versa. Using our robust study design, we find that protected areas have a mixed impact on waterbirds, with a strong signal that areas managed for waterbirds or their habitat are more likely to benefit populations, and a weak signal that larger areas are more beneficial than smaller ones. Calls to conserve 30% of the Earth's surface by 2030 are gathering pace14, but we show that protection alone does not guarantee good biodiversity outcomes. As countries gather to agree the new Global Biodiversity Framework, targets must focus on creating and supporting well-managed protected and conserved areas that measurably benefit populations.
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Aves , Conservación de los Recursos Naturales , Animales , Biodiversidad , EcosistemaRESUMEN
Conservation increasingly relies on social science tools to understand human behavior. Specialized questioning techniques (SQTs) are a suite of methods designed to reduce bias in social surveys and are widely used to collect data on sensitive topics, including compliance with conservation rules. Most SQTs have been developed in Western, industrialized, educated, rich, and democratic countries, meaning their suitability in other contexts may be limited. Whether these techniques perform better than conventional direct questioning is important for those considering their use. We designed an experiment to validate the performance of four SQTs (unmatched count technique, randomized response technique, crosswise model, and bean method) against direct questions when asking about a commonly researched sensitive behavior in conservation, wildlife hunting. We developed fictional characters, and for each method asked respondents to report the answers that each fictional character should give when asked if they hunt wildlife. We collected data from 609 individuals living close to protected areas in two different cultural and socioeconomic contexts (Indonesia and Tanzania) to quantify the extent to which respondents understood and followed SQT instructions and to explore the sociodemographic factors that influenced a correct response. Data were modeled using binomial general linear mixed models. Participants were more likely to refuse to answer questions asked using SQTs compared with direct questions. Model results suggested that SQTs were harder for participants to understand. Demographic factors (e.g., age and education level) significantly influenced response accuracy. When sensitive responses to sensitive questions were required, all SQTs (excluding the bean method) outperformed direct questions, demonstrating that SQTs can successfully reduce sensitivity bias. However, when reviewing each method, most respondents (59-89%) reported they would feel uncomfortable using them to provide information on their own hunting behavior, highlighting the considerable challenge of encouraging truthful reporting on sensitive topics. Our results demonstrate the importance of assessing the suitability of social science methods prior to their implementation in conservation contexts.
Validación Experimental de las Técnicas de Cuestionamiento Especializado en la Conservación Resumen La conservación depende cada vez más de herramientas de las ciencias sociales para entender el comportamiento humano. Las técnicas de cuestionamiento especializado (TCE) son un conjunto de métodos diseñados para reducir el sesgo en los censos sociales y y se usan ampliamente para recolectar datos sobre temas sensibles, incluyendo el cumplimiento de las normas de conservación. La mayoría de las TCE se desarrollaron en el hemisferio occidental, en países industrializados, educados, ricos y democráticos, lo que significa que su que su idoneidad en otros contextos puede ser limitada. Quienes piensan en usar estas técnicas consideran importante saber si tienen un mejor desempeño que el cuestionamiento directo convencional. Diseñamos un experimento para validar el desempeño de cuatro TCE (técnica de conteo sin par, técnica de respuesta aleatoria, modelo transversal, método bean) frente a las preguntas directas cuando se cuestiona sobre un comportamiento sensible de interés recurrente en la conservación: la cacería de fauna. Desarrollamos personajes ficticios y para cada método le pedimos a los respondientes que reportaran las respuestas que cada personaje ficticio debería dar al cuestionársele si cazan fauna silvestre. Recolectamos datos de 609 individuos con residencia cercana a áreas protegidas en dos contextos cultural y socioeconómicamente diferentes (Indonesia y Tanzanía) para cuantificar el grado al que los respondientes entendieron y siguieron las instrucciones de las TCE y para explorar los factores sociodemográficos que influyeron sobre las respuestas correctas. Modelamos los datos mediante modelos lineales mixtos binomiales y generales. Fue más probable que los participantes se rehusaran a responder las preguntas realizadas con las TCE en comparación con las preguntas directas. Los resultados del modelo sugirieron que las TCE eran más difíciles de entender para los participantes. Los factores demográficos (p. ej.: edad y nivel educativo) influyeron significativamente la certeza de las respuestas. Cuando se requirieron respuestas sensibles a preguntas sensibles, todas las TCE (excepto el método bean) tuvieron un mejor desempeño que las preguntas directas, lo que demuestra que las TCE pueden reducir exitosamente el sesgo por sensibilidad. Sin embargo, cuando se les preguntó sobre cada método, la mayoría de los respondientes (59-89%) reportó que se sentirían incómodos si tuvieran que usarlas para proporcionar información sobre sus propios comportamientos de cacería, lo que destaca el reto considerable que es reportar honestamente los temas sensibles. Nuestros resultados demuestran la importancia de de evaluar la idoneidad de los métodos de las ciencias sociales previo a su implementación en contextos de conservación.
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Conservación de los Recursos Naturales , Humanos , Indonesia , Encuestas y Cuestionarios , TanzaníaRESUMEN
Attempts to link human development and biodiversity conservation goals remain a constant feature of policy and practice related to protected areas (PAs). Underlying these approaches are narratives that simplify assumptions, shaping how interventions are designed and implemented. We examine evidence for five key narratives: 1) conservation is pro-poor; 2) poverty reduction benefits conservation; 3) compensation neutralises costs of conservation; 4) local participation is good for conservation; 5) secure tenure rights for local communities support effective conservation. Through a mixed-method synthesis combining a review of 100 peer-reviewed papers and 25 expert interviews, we examined if and how each narrative is supported or countered by the evidence. The first three narratives are particularly problematic. PAs can reduce material poverty, but exclusion brings substantial local costs to wellbeing, often felt by the poorest. Poverty reduction will not inevitably deliver on conservation goals and trade-offs are common. Compensation (for damage due to human wildlife conflict, or for opportunity costs), is rarely sufficient or commensurate with costs to wellbeing and experienced injustices. There is more support for narratives 4 and 5 on participation and secure tenure rights, highlighting the importance of redistributing power towards Indigenous Peoples and Local Communities in successful conservation. In light of the proposed expansion of PAs under the post-2020 Global Biodiversity Framework, we outline implications of our review for the enhancement and implementation of global targets in order to proactively integrate social equity into conservation and the accountability of conservation actors.
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Conservation increasingly seeks knowledge of human behaviour. However, securing reliable data can be challenging, particularly if the behaviour is illegal or otherwise sensitive. Specialised questioning methods such as Randomised Response Techniques (RRTs) are increasingly used in conservation to provide greater anonymity, increase response rates, and reduce bias. A rich RRT literature exists, but successfully navigating it can be challenging. To help conservationists access this literature, we summarise the various RRT designs available and conduct a systematic review of empirical applications of RRTs within (n = 32), and beyond conservation (n = 66). Our results show increased application of RRTs in conservation since 2000. We compare the performance of RRTs against known prevalence of the sensitive behaviour and relative to other questioning techniques to assess how successful RRTs are at reducing bias (indicated by securing higher estimates). Findings suggest that RRT applications in conservation were less likely than those in other disciplines to provide prevalence estimates equal to, or higher than those derived from direct questions. Across all disciplines, we found reports of non-compliance with RRT instructions were common, but rarely accounted for in study design or analysis. For the first time, we provide conservationists considering RRTs with evidence on what works, and provide guidance on how to develop robust designs suitable for conservation research contexts. We highlight when alternate methods should be used, how to increase design efficiency and improve compliance with RRT instructions. We conclude RRTs are a useful tool, but their performance depends on careful design and implementation.
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Human activities are degrading ecosystems worldwide, posing existential threats for biodiversity and humankind. Slowing and reversing this degradation will require profound and widespread changes to human behaviour. Behavioural scientists are therefore well placed to contribute intellectual leadership in this area. This Perspective aims to stimulate a marked increase in the amount and breadth of behavioural research addressing this challenge. First, we describe the importance of the biodiversity crisis for human and non-human prosperity and the central role of human behaviour in reversing this decline. Next, we discuss key gaps in our understanding of how to achieve behaviour change for biodiversity conservation and suggest how to identify key behaviour changes and actors capable of improving biodiversity outcomes. Finally, we outline the core components for building a robust evidence base and suggest priority research questions for behavioural scientists to explore in opening a new frontier of behavioural science for the benefit of nature and human wellbeing.
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Ciencias de la Conducta , Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Investigación Conductal , HumanosRESUMEN
Humanity's impact on the environment is increasing, as are strategies to conserve biodiversity, but a lack of understanding about how interventions affect ecological and conservation outcomes hampers decision-making. Time series are often used to assess impacts, but ecologists tend to compare average values from before to after an impact; overlooking the potential for the intervention to elicit a change in trend. Without methods that allow for a range of responses, erroneous conclusions can be drawn, especially for large, multi-time-series datasets, which are increasingly available. Drawing on literature in other disciplines and pioneering work in ecology, we present a standardised framework to robustly assesses how interventions, like natural disasters or conservation policies, affect ecological time series.
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Biodiversidad , Conservación de los Recursos Naturales , EcologíaRESUMEN
Many nations use ecological compensation policies to address negative impacts of development projects and achieve No Net Loss (NNL) of biodiversity and ecosystem services. Yet, failures are widely reported. We use spatial simulation models to quantify potential net impacts of alternative compensation policies on biodiversity (indicated by native vegetation) and two ecosystem services (carbon storage, sediment retention) across four case studies (in Australia, Brazil, Indonesia, Mozambique). No policy achieves NNL of biodiversity in any case study. Two factors limit their potential success: the land available for compensation (existing vegetation to protect or cleared land to restore), and expected counterfactual biodiversity losses (unregulated vegetation clearing). Compensation also fails to slow regional biodiversity declines because policies regulate only a subset of sectors, and expanding policy scope requires more land than is available for compensation activities. Avoidance of impacts remains essential in achieving NNL goals, particularly once opportunities for compensation are exhausted.
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The negative environmental and economic impacts of many invasive species are well known. However, given the increased homogenization of global biota, and the difficulty of eradicating species once established, a balanced approach to considering the impacts of invasive species is needed. The marbled crayfish (Procambarus virginalis) is a parthenogenetic freshwater crayfish that was first observed in Madagascar around 2005 and has spread rapidly. We present the results of a socio-economic survey (n = 385) in three regions of Madagascar that vary in terms of when the marbled crayfish first arrived. Respondents generally considered marbled crayfish to have a negative impact on rice agriculture and fishing, however the animals were seen as making a positive contribution to household economy and food security. Regression modeling showed that respondents in regions with longer experience of marbled crayfish have more positive perceptions. Unsurprisingly, considering the perception that crayfish negatively impact rice agriculture, those not involved in crayfish harvesting and trading had more negative views towards the crayfish than those involved in crayfish-related activities. Food preference ranking and market surveys revealed the acceptance of marbled crayfish as a cheap source of animal protein; a clear positive in a country with widespread malnutrition. While data on biodiversity impacts of the marbled crayfish invasion in Madagascar are still completely lacking, this study provides insight into the socio-economic impacts of the dramatic spread of this unique invasive species. "Biby kely tsy fantam-piaviana, mahavelona fianakaviana" (a small animal coming from who knows where which supports the needs of the family). Government worker Analamanga, Madagascar.