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471.
Market-based conservation mechanisms are designed to facilitate the mitigation of harm to and conservation of habitats and biodiversity. Their potential is partly hindered, however, by the quantification tools used to assess habitat quality and functionality. Of specific concern are the lack of transparency and standardization in tool development and gaps in tool availability. To address these issues, we collected information via internet and literature searchers and through conversations with tool developers and users on tools used in U.S. conservation mechanisms, such as payments for ecosystem services (PES) and ecolabel programs, conservation banking, and habitat exchanges. We summarized information about tools and explored trends among and within mechanisms based on criteria detailing geographic, ecological, and technical features of tools. We identified 69 tools that assessed at least 34 species and 39 habitat types. Where tools reported pricing, 98% were freely available. More tools were applied to states along the U.S. West Coast than elsewhere, and the level of tool transferability varied markedly among mechanisms. Tools most often incorporated conditions at numerous spatial scales, frequently addressed multiple risks to site viability, and required 1–83 data inputs. Most tools required a moderate or greater level of user skill. Average tool-complexity estimates were similar among all mechanisms except PES programs. Our results illustrate the diversity among tools in their ecological features, data needs, and geographic application, supporting concerns about a lack of standardization. However, consistency among tools in user skill requirements, incorporation of multiple spatial scales, and complexity highlight important commonalities that could serve as a starting point for establishing more standardized tool development and feature-incorporation processes. Greater standardization in tool design may expand market participation and facilitate a needed assessment of the effectiveness of market-based conservation. 相似文献
472.
Wildlife corridors aim to promote species’ persistence by connecting habitat patches across fragmented landscapes. Their implementation is limited by patterns of land ownership and complicated by differences in the jurisdictional and regulatory authorities under which lands are managed. Terrestrial corridor conservation requires coordination across jurisdictions and sectors subject to site-specific overlapping sources of legal authority. Mapping spatial patterns of legal authority concurrent with habitat condition can illustrate opportunities to build or leverage capacity for connectivity conservation. Streamside areas provide pragmatic opportunities to leverage existing policy mechanisms for riverine and terrestrial habitat connectivity across boundaries. Conservation planners and practitioners can make use of these opportunities by harmonizing actions for multiple conservation outcomes. We formulated an integrative, data-driven method for mapping multiple sources of legal authority weighted by capacity for coordinating terrestrial habitat conservation along streams. We generated a map of capacity to coordinate streamside corridor protections across a wildlife habitat gap to demonstrate this approach. We combined values representing coordination capacity and naturalness to generate an integrated legal-ecological resistance map for connectivity modeling. We then computed least-cost corridors across the integrated map, masking the terrestrial landscape to focus on streamside areas. Streamside least-cost corridors in the integrated, local-scale model diverged (∼25 km) from national-scale least-cost corridors based on naturalness. Spatial categories comparing legal- and naturalness-based resistance values by stream reach highlighted potential locations for building or leveraging existing capacity through spatial coordination of policy mechanisms or restoration actions. Agencies or nongovernmental organizations intending to restore or maintain habitat connectivity across fragmented landscapes can use this approach to inform spatial prioritization and build coordination capacity. Article impact statement: Combined mapping of legal authority and habitat condition reveals capacity to coordinate actions along streams for clean water and wildlife. 相似文献
473.
Michael J. Manfredo Tara L. Teel Andrew W. Don Carlos Leeann Sullivan Alan D. Bright Alia M. Dietsch Jeremy Bruskotter David Fulton 《Conservation biology》2020,34(6):1549-1559
We introduced a multilevel model of value shift to describe the changing social context of wildlife conservation. Our model depicts how cultural-level processes driven by modernization (e.g., increased wealth, education, and urbanization) affect changes in individual-level cognition that prompt a shift from domination to mutualism wildlife values. Domination values promote beliefs that wildlife should be used primarily to benefit humans, whereas mutualism values adopt a view that wildlife are part of one's social network and worthy of care and compassion. Such shifts create emergent effects (e.g., new interest groups) and challenges to wildlife management organizations (e.g., increased conflict) and dramatically alter the sociopolitical context of conservation decisions. Although this model is likely applicable to many modernized countries, we tested it with data from a 2017–2018 nationwide survey (mail and email panel) of 43,949 residents in the United States. We conducted hierarchical linear modeling and correlational analysis to examine relationships. Modernization variables had strong state-level effects on domination and mutualism. Higher levels of education, income, and urbanization were associated with higher percentages of mutualists and lower percentages of traditionalists, who have strong domination values. Values affected attitudes toward wildlife management challenges; for example, states with higher proportions of mutualists were less supportive of lethal control of wolves (Canis lupus) and had lower percentages of active hunters, who represent the traditional clientele of state wildlife agencies in the United States. We contend that agencies will need to embrace new strategies to engage and represent a growing segment of the public with mutualism values. Our model merits testing for application in other countries. 相似文献
474.
Gavin McDonald Molly Wilson Diogo Veríssimo Rebecca Twohey Michaela Clemence Dean Apistar Stephen Box Paul Butler Fel Cesar Cadiz Stuart J. Campbell Courtney Cox Micah Effron Steve Gaines Raymond Jakub Roquelito H. Mancao Pablo T. Rojas Rocky Sanchez Tirona Gabriel Vianna 《Conservation biology》2020,34(5):1176-1189
Small-scale fisheries are an important livelihood and primary protein source for coastal communities in many of the poorest regions in the world, yet many are overfished and thus require effective and scalable management solutions. Positive ecological and socioeconomic responses to management typically lag behind immediate costs borne by fishers from fishing pressure reductions necessary for fisheries recovery. These short-term costs challenge the long-term success of these interventions. However, social marketing may increase perceptions of management benefits before ecological and socioeconomic benefits are fully realized, driving new social norms and ultimately long-term sustainable behavior change. By conducting underwater visual surveys to quantify ecological conditions and by conducting household surveys with community members to quantify their perceptions of management support and socioeconomic conditions, we assessed the impact of a standardized small-scale fisheries management intervention that was implemented across 41 sites in Brazil, Indonesia, and the Philippines. The intervention combines TURF reserves (community-based territorial use rights for fishing coupled with no-take marine reserves) with locally tailored social-marketing behavior change campaigns. Leveraging data across 22 indicators and 4 survey types, along with data from 3 control sites, we found that ecological and socioeconomic impacts varied and that communities supported the intervention and were already changing their fishing practices. These results suggest that communities were developing new social norms and fishing more sustainably before long-term ecological and socioeconomic benefits of fisheries management materialized. 相似文献
475.
476.
Ocon CS Rodrigues Capítulo A Paggi AC 《Environmental pollution (Barking, Essex : 1987)》2008,156(1):82-89
The objective of this work was to analyse zoobenthic assemblages in the coastal sector of the Río de La Plata, Argentina, after a petroleum spill. Sampling stations were located in representative sites of various landscapes. Structure, composition, physico-chemical parameters and seasonal changes were recorded in order to assess taxocenosis evolution during the period 1999–2003. Recovery signs were estimated by means of biotic indices and the presence of sensitive species. Tolerant species were dominant in heavily polluted sites, with low diversity and water quality values, according to the biotic indices used. In certain zones, sediment quality remains impoverished, with a visible oil film on the surface. However, during the last sampling, some points showed an increase in biotic indices, pointing to a slight improvement in environmental conditions. 相似文献
477.
Abstract: The commercial trade of wildlife occurs on a global scale. In addition to removing animals from their native populations, this trade may lead to the release and subsequent introduction of nonindigenous species and the pathogens they carry. Emerging infectious diseases, such as chytridiomycosis caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), and ranaviral disease have spread with global trade in amphibians and are linked to amphibian declines and die‐offs worldwide, which suggests that the commercial trade in amphibians may be a source of pathogen pollution. We screened tiger salamanders involved in the bait trade in the western United States for both ranaviruses and Bd with polymerase chain reaction and used oral reports from bait shops and ranavirus DNA sequences from infected bait salamanders to determine how these animals and their pathogens are moved geographically by commerce. In addition, we conducted 2 surveys of anglers to determine how often tiger salamanders are used as bait and how often they are released into fishing waters by anglers, and organized bait‐shop surveys to determine whether tiger salamanders are released back into the wild after being housed in bait shops. Ranaviruses were detected in the tiger salamander bait trade in Arizona, Colorado, and New Mexico, and Bd was detected in Arizona bait shops. Ranaviruses were spread geographically through the bait trade. All tiger salamanders in the bait trade were collected from the wild, and in general they moved east to west and north to south, bringing with them their multiple ranavirus strains. Finally, 26–73% of anglers used tiger salamanders as fishing bait, 26–67% of anglers released tiger salamanders bought as bait into fishing waters, and 4% of bait shops released tiger salamanders back into the wild after they were housed in shops with infected animals. The tiger salamander bait trade in the western United States is a useful model for understanding the consequences of the unregulated anthropogenic movement of amphibians and their pathogens through trade. 相似文献
478.
Sébastien Desbureaux 《Conservation biology》2021,35(5):1615-1626
Arbitrary modeling choices are inevitable in scientific studies. Yet, few empirical studies in conservation science report the effects these arbitrary choices have on estimated results. I explored the effects of subjective modeling choices in the context of counterfactual impact evaluations. Over 5000 candidate models based on reasonable changes in the choice of statistical matching algorithms (e.g., genetic and nearest distance mahalanobis matching), the parametrization of these algorithms (e.g., number of matches), and the inclusion of specific covariates (e.g., distance to nearest city, slope, or rainfall) were valid for studying the effect of Virunga National Park in Democratic Republic of the Congo on changes in tree cover loss and carbon storage over time. I randomly picked 2000 of the 5000 candidate models to determine how much and which subjective modeling choices affected the results the most. All valid models indicated that tree cover loss decreased and carbon storage increased in Virunga National Park from 2000 to 2019. Nonetheless, the order of magnitude of the estimates varied by a factor of 3 (from −4.78 to −13.12 percentage points decrease in tree cover loss and from 20 to 46 t Ce/ha for carbon storage). My results highlight that modeling choices, notably the choice of the matching algorithm, can have significant effects on point estimates and suggest that more structured robustness checks are a key step toward more credible findings in conservation science. 相似文献
479.
Sophie S. Parker Gregory B. Pauly James Moore Naomi S. Fraga John J. Knapp Zachary Principe Brian V. Brown John M. Randall Brian S. Cohen Thomas A. Wake 《Conservation biology》2018,32(5):1007-1019
When conservation strategies require new, field‐based information, practitioners must find the best ways to rapidly deliver high‐quality survey data. To address this challenge, several rapid‐assessment approaches have been developed since the early 1990s. These typically involve large areas, take many months to complete, and are not appropriate when conservation‐relevant survey data are urgently needed for a specific locale. In contrast, bioblitzes are designed for quick collection of site‐specific survey data. Although bioblitzes are commonly used to achieve educational or public‐engagement goals, conservation practitioners are increasingly using a modified bioblitz approach to generate conservation‐relevant data while simultaneously enhancing research capacity and building working partnerships focused on conservation concerns. We term these modified events expert bioblitzes. Several expert bioblitzes have taken place on lands of conservation concern in Southern California and have involved collaborative efforts of government agencies, nonprofit organizations, botanic gardens, museums, and universities. The results of expert bioblitzes directly informed on‐the‐ground conservation and decision‐making; increased capacity for rapid deployment of expert bioblitzes in the future; and fostered collaboration and communication among taxonomically and institutionally diverse experts. As research and conservation funding becomes increasingly scarce, expert bioblitzes can play an increasingly important role in biodiversity conservation. 相似文献
480.
Time discounting and the decision to protect areas that are near and threatened or remote and cheap to acquire
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Paul R. Armsworth 《Conservation biology》2018,32(5):1063-1073
Should conservation organizations focus on protecting habitats that are at imminent risk of being converted but are expensive or more remote areas that are less immediately threatened but where a large amount of land can be set aside? Variants of this trade‐off commonly arise in spatial planning. I used models of land‐use change near a deforestation frontier to examine this trade‐off. The optimal choice of where to protect was determined by how decisions taken today accounted for ecological benefits and economic costs of conservation actions that would occur sometime in the future. I used an ecological and economic discount rate to weight these benefits and costs. A large economic discount rate favored protecting more remote areas, whereas a large, positive ecological discount rate favored protecting habitat near the current deforestation frontier. The decision over where to protect was also affected by the influence economic factors had on landowners' decisions, the rate of technological change, and ecological heterogeneity of the landscape. How benefits and costs through time are accounted for warrants careful consideration when specifying conservation objectives. It may provide a niche axis along which conservation organizations differentiate themselves when competing for donor funding or other support. 相似文献