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31.
All U.S. federal agencies administering environmental laws purport to practice adaptive management (AM), but little is known about how they actually implement this conservation tool. A gap between the theory and practice of AM is revealed in judicial decisions reviewing agency adaptive management plans. We analyzed all U.S. federal court opinions published through 1 January 2015 to identify the agency AM practices courts found most deficient. The shortcomings included lack of clear objectives and processes, monitoring thresholds, and defined actions triggered by thresholds. This trio of agency shortcuts around critical, iterative steps characterizes what we call AM‐lite. Passive AM differs from active AM in its relative lack of management interventions through experimental strategies. In contrast, AM‐lite is a distinctive form of passive AM that fails to provide for the iterative steps necessary to learn from management. Courts have developed a sophisticated understanding of AM and often offer instructive rather than merely critical opinions. The role of the judiciary is limited by agency discretion under U.S. administrative law. But courts have overturned some agency AM‐lite practices and insisted on more rigorous analyses to ensure that the promised benefits of structured learning and fine‐tuned management have a reasonable likelihood of occurring. Nonetheless, there remains a mismatch in U.S. administrative law between the flexibility demanded by adaptive management and the legal objectives of transparency, public participation, and finality.  相似文献   
32.
Unsustainable hunting outside protected areas is threatening tropical biodiversity worldwide and requires conservationists to engage increasingly in antipoaching activities. Following the example of ecocertified logging companies, we argue that other extractive industries managing large concessions should engage in antipoaching activities as part of their environmental management plans. Onshore hydrocarbon concessions should also adopt antipoaching protocols as a standard because they represent a biodiversity threat comparable to logging. We examined the spatiotemporal patterns of small‐ and large‐mammal poaching in an onshore oil concession in Gabon, Central Africa, with a Bayesian occupancy model based on signs of poaching collected from 2010 to 2015 on antipoaching patrols. Patrol locations were initially determined based on local intelligence and past patrol successes (adaptive management) and subsequently with a systematic sampling of the concession. We generated maps of poaching probability in the concession and determined the temporal trends of this threat over 5 years. The spatiotemporal patterns of large‐ and small‐mammal poaching differed throughout the concession, and likely these groups will need different management strategies. By elucidating the relationship between site‐specific sampling effort and detection probability, the Bayesian method allowed us to set goals for future antipoaching patrols. Our results indicate that a combination of systematic sampling and adaptive management data is necessary to infer spatiotemporal patterns with the statistical method we used. On the basis of our case study, we recommend hydrocarbon companies interested in implementing efficient antipoaching activities in their onshore concessions to lay the foundation of long‐needed industry standards by: adequately measuring antipoaching effort; mixing adaptive management and balanced sampling; setting goals for antipoaching effort; pairing patrols with large‐mammal monitoring; supporting antipoaching patrols across the landscape; restricting access to their concessions; performing random searches for bushmeat and mammal products at points of entry; controlling urban and agricultural expansion; supporting bushmeat alternatives; and supporting land‐use planning.  相似文献   
33.
Agriculturally altered vegetation, especially oil‐palm plantations, is rapidly increasing in Southeast Asia. Low species diversity is associated with this commodity, but data on anuran diversity in oil‐palm plantations are lacking. We investigated how anuran biological diversity differs between forest and oil‐palm plantation, and whether observed differences in biological diversity of these areas is linked to specific environmental factors. We hypothesized that biological diversity is lower in plantations and that plantations support a larger proportion of disturbance‐tolerant species than forest. We compared species richness, abundance, and community composition between plantation and forest areas and between site types within plantation and forest (forest stream vs. plantation stream, forest riparian vs. plantation riparian, forest terrestrial vs. plantation terrestrial). Not all measures of biological diversity differed between oil‐palm plantations and secondary forest sites. Anuran community composition, however, differed greatly between forest and plantation, and communities of anurans in plantations contained species that prosper in disturbed areas. Although plantations supported large numbers of breeding anurans, we concluded the community consisted of common species that were of little conservation concern (commonly found species include Fejervarya limnocharis, Microhyla heymonsi, and Hylarana erythrea). We believe that with a number of management interventions, oil‐palm plantations can provide habitat for species that dwell in secondary forests. Efectos de las Plantaciones de Palma de Aceite sobre la Diversidad de Anuros Tropicales Faruk et al.  相似文献   
34.
In managed natural resource systems, such as fisheries and rangelands, there is a recognized trade‐off between managing for short‐term benefits and managing for longer term resilience. Management actions that stabilize ecological attributes or processes can improve productivity in the supply of ecosystem goods and services in the short term but erode system resilience at longer time scales. For example, fire suppression in rangelands can increase grass biomass initially but ultimately result in an undesirable, shrub‐dominated system. Analyses of this phenomenon have focused largely on how management actions influence slow‐changing biophysical system attributes (such as vegetation composition). Data on the frequency of management actions that reduce natural ecological variation on 66 private land‐conservation areas (PLCAs) in South Africa were used to investigate how management actions are influenced by manager decision‐making approaches, a largely ignored part of the problem. The pathology of natural resource management was evident on some PLCAs: increased focus on revenue‐generation in decision making resulted in an increased frequency of actions to stabilize short‐term variation in large mammal populations, which led to increased revenues from ecotourism or hunting. On many PLCAs, these management actions corresponded with a reduced focus on ecological monitoring and an increase in overstocking of game (i.e., ungulate species) and stocking of extralimitals (i.e., game species outside their historical range). Positives in natural resource management also existed. Some managers monitored slower changing ecological attributes, which resulted in less‐intensive management, fewer extralimital species, and lower stocking rates. Our unique, empirical investigation of monitoring‐management relationships illustrates that management decisions informed by revenue monitoring versus ecological monitoring can have opposing consequences for natural resource productivity and sustainability. Promoting management actions that maintain resilience in natural resource systems therefore requires cognizance of why managers act the way they do and how these actions can gradually shift managers toward unsustainable strategies.  相似文献   
35.
Many organisms live in networks of local populations connected by dispersing individuals, called spatially structured populations (SSPs), where the long-term persistence of the entire network is determined by the balance between 2 processes acting at the scale of local populations: extinction and colonization. When multiple threats act on an SSP, a comparison of the different factors determining local extinctions and colonizations is essential to plan sound conservation actions. We assessed the drivers of long-term population dynamics of multiple amphibian species at the regional scale. We used dynamic occupancy models within a Bayesian framework to identify the factors determining persistence and colonization of local populations. Because connectivity among patches is fundamental to SSPs dynamics, we considered 2 measures of connectivity acting on each focal patch: incidence of the focal species and incidence of invasive crayfish. We used meta-analysis to summarize the effect of different drivers at the community level. Persistence and colonization of local populations were jointly determined by factors acting at different scales. Persistence probability was positively related to the area and the permanence of wetlands, whereas it was negatively related to occurrence of fish. Colonization probability was highest in semipermanent wetlands and in sites with a high incidence of the focal species in nearby sites, whereas it showed a negative relationship with the incidence of invasive crayfish in the landscape. By analyzing long-term data on amphibian population dynamics, we found a strong effect of some classic features commonly used in SSP studies, such as patch area and focal species incidence. The presence of an invasive non-native species at the landscape scale emerged as one of the strongest drivers of colonization dynamics, suggesting that studies on SSPs should consider different connectivity measures more frequently, such as the incidence of predators, especially when dealing with biological invasions.  相似文献   
36.
Herbarium specimens are increasingly recognized as an important resource for conservation science and virtual herbaria are making specimens freely available to a wider range of users than ever before. Few virtual herbaria are designed with conservation use as a primary driver. Exceptionally, Brazil's Reflora Virtual Herbarium (RVH) was created to increase knowledge and conservation of the Brazilian flora. The RVH is closely integrated with the Flora of Brazil 2020 platform on which Brazil's new national Flora is under construction. Both resources are accessible via the Reflora home page and thousands of users move seamlessly between these Reflora resources. To understand how the Reflora resources are currently used and their impact on conservation science, we conducted a literature review and an online survey. We searched for publications of studies in which Reflora resources were used and publications resulting from Brazilian researchers who were part of Reflora's research and mobility program. The survey contained multiple choice questions and questions that required a written response. We targeted Reflora webpage visitors with the survey to capture a wider range of Reflora users than the literature review. Reflora resources were used for a variety of conservation-relevant purposes. Half the 806 scientific publications in which Reflora was cited and 81% of the 1069 survey respondents accessing Reflora resources mentioned conservation-relevant research outputs. Most conservation-relevant uses of the Reflora resources in scientific publications were research rather than implementation focused. The survey of Reflora users showed conservation uses and impacts of virtual herbaria were more numerous and diverse than the uses captured in the literature review. Virtual herbaria are vital resources for conservation science, but they must document use and impacts more comprehensively to ensure sustainability.  相似文献   
37.
Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.  相似文献   
38.
Abstract: Biodiversity is too complex to measure directly, so conservation planning must rely on surrogates to estimate the biodiversity of sites. The species richness of selected taxa is often used as a surrogate for the richness of other taxa. Surrogacy values of taxa have been evaluated in diverse contexts, yet broad trends in their effectiveness remain unclear. We reviewed published studies testing the ability of species richness of surrogate taxa to capture the richness of other (target) taxa. We stratified studies into two groups based on whether a complementarity approach (surrogates used to select a combination of sites that together maximize total species richness for the taxon) or a richness‐hotspot approach (surrogates used to select sites containing the highest species richness for the taxon) was used. For each comparison of one surrogate taxon with one target, we used the following predictor variables: biome, spatial extent of study area, surrogate taxon, and target taxon. We developed a binary response variable based on whether the surrogate taxon provided better than random representation of the target taxon. For studies that used an evaluation approach that was not based on better than random representation of target taxa, we based the response variable on the interpretation of results in the original study. We performed a categorical regression to elucidate trends in the effectiveness of surrogate taxa with regard to each of the predictor variables. A surrogate was 25% more likely to be effective with a complementarity approach than with a hotspot approach. For hotspot‐based approaches, biome, extent of study, surrogate taxon, and target taxon significantly influenced effectiveness of the surrogate. For complementarity‐based approaches, biome, extent, and surrogate taxon significantly influenced effectiveness of the surrogate. For all surrogate evaluations, biome explained the greatest amount of variation in surrogate effectiveness. From most to least, extent, surrogate taxon, and target taxon explained the most variation after biome. Surrogate taxa were most effective in grasslands and in some cases boreal zones, deserts, and tropical forests; surrogate taxa also were more effective in studies examining larger areas. Herpetofauna were the most effective taxon as both surrogate and target when a richness‐hotspot approach was used; however, herpetofauna were analyzed in fewer studies, so this result is tentative. For complementarity approaches, taxa that are easy to measure and tend to have a large number of habitat specialists distributed collectively across broad environmental gradients (e.g., plants, birds, and mammals) were the most effective surrogates.  相似文献   
39.
Abstract: Social, economic, and ecological criteria contribute to the successful design, implementation, and management of marine protected areas (MPAs). In the context of California's Marine Life Protection Act Initiative, we developed a set of methods for collecting, compiling, and analyzing data about the spatial extent and relative economic importance of commercial and recreational fishing. We interviewed 174 commercial fishers who represented the major fisheries in the initiative's north‐central coast region, which extends from Point Arena south to Pigeon Point. These fishers provided data that we used to map the extent of each of the fishing grounds, to weight the relative importance of areas within the grounds, to characterize the operating costs of each fishery, and to analyze the potential economic losses associated with proposed marine protected areas. A regional stakeholder group used the maps and impact analyses in conjunction with other data sets to iteratively identify economic and ecological trade‐offs in designations of different areas as MPAs at regional, port, and fishery extents. Their final proposed MPA network designated 20% of state waters as MPAs. Potential net economic loss ranged from 1.7% to 14.2% in the first round of network design and totaled 6.3% in the final round of design. This process is a case study in the application of spatial analysis to validate and integrate local stakeholder knowledge in marine planning.  相似文献   
40.
Abstract: There is a growing recognition that conservation often entails trade‐offs. A focus on trade‐offs can open the way to more complete consideration of the variety of positive and negative effects associated with conservation initiatives. In analyzing and working through conservation trade‐offs, however, it is important to embrace the complexities inherent in the social context of conservation. In particular, it is important to recognize that the consequences of conservation activities are experienced, perceived, and understood differently from different perspectives, and that these perspectives are embedded in social systems and preexisting power relations. We illustrate the role of trade‐offs in conservation and the complexities involved in understanding them with recent debates surrounding REDD (Reducing Emissions from Deforestation and Degradation), a global conservation policy designed to create incentives to reduce tropical deforestation. Often portrayed in terms of the multiple benefits it may provide: poverty alleviation, biodiversity conservation, and climate‐change mitigation; REDD may involve substantial trade‐offs. The gains of REDD may be associated with a reduction in incentives for industrialized countries to decrease carbon emissions; relocation of deforestation to places unaffected by REDD; increased inequality in places where people who make their livelihood from forests have insecure land tenure; loss of biological and cultural diversity that does not directly align with REDD measurement schemes; and erosion of community‐based means of protecting forests. We believe it is important to acknowledge the potential trade‐offs involved in conservation initiatives such as REDD and to examine these trade‐offs in an open and integrative way that includes a variety of tools, methods, and points of view.  相似文献   
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