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How Do Any Species Persist? Lessons for Conservation Biology   总被引:1,自引:0,他引:1  
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Abstract: An essential foundation of any science is a standard lexicon. Any given conservation project can be described in terms of the biodiversity targets, direct threats, contributing factors at the project site, and the conservation actions that the project team is employing to change the situation. These common elements can be linked in a causal chain, which represents a theory of change about how the conservation actions are intended to bring about desired project outcomes. If project teams want to describe and share their work and learn from one another, they need a standard and precise lexicon to specifically describe each node along this chain. To date, there have been several independent efforts to develop standard classifications for the direct threats that affect biodiversity and the conservation actions required to counteract these threats. Recognizing that it is far more effective to have only one accepted global scheme, we merged these separate efforts into unified classifications of threats and actions, which we present here. Each classification is a hierarchical listing of terms and associated definitions. The classifications are comprehensive and exclusive at the upper levels of the hierarchy, expandable at the lower levels, and simple, consistent, and scalable at all levels. We tested these classifications by applying them post hoc to 1191 threatened bird species and 737 conservation projects. Almost all threats and actions could be assigned to the new classification systems, save for some cases lacking detailed information. Furthermore, the new classification systems provided an improved way of analyzing and comparing information across projects when compared with earlier systems. We believe that widespread adoption of these classifications will help practitioners more systematically identify threats and appropriate actions, managers to more efficiently set priorities and allocate resources, and most important, facilitate cross‐project learning and the development of a systematic science of conservation.  相似文献   
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Abstract: Amazonia is a highly threatened rainforest that encompasses a major proportion of Earth's biological diversity. Our main goal was to establish conservation priorities for Amazonia's areas of endemism on the basis of measures of evolutionary distinctiveness. We considered two previously identified sets of areas of endemism. The first set consisted of eight large areas used traditionally in biogeographical studies: Belém, Tapajós, Xingu, Guiana, Rondônia, Imeri, Inambari, and Napo. The second set consisted of 16 smaller areas that were subdivisions of the larger areas. We assembled a data set of 50 phylogenies that represented 16 orders and 1715 distributional records. We identified priority conservation areas for the areas of endemism according to node‐based metrics of evolutionary distinctiveness. We contrasted these results with priority areas identified on the basis of raw species richness and species endemicity. For the larger areas, we identified Guiana and Inambari as the first‐ and second‐most important areas for conservation. The remaining areas in this first group scored half (e.g., Napo) or less than Guiana and Inambari on all indices. For the smaller areas, a subdivision of Guiana (i.e., Guyana and the Brazilian states of Roraima and Amazonas) was at the top of the ranking and was followed by a subdivision of Inambari (i.e., northwestern portion of Amazonas) and then another subdivision of Guiana (i.e., Suriname, French Guiana, and the Brazilian state of Amapá). The distinctiveness‐based rankings of the priority of areas correlated directly with those derived from species richness and species endemicity. Current conservation strategies in Amazonia, although they rely on many other criteria apart from phylogeny, are focusing on the most important areas for conservation we identified here.  相似文献   
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Abstract: Lethal control, which has been used to reduce local abundances of animals in conflict with humans or with endangered species, may not achieve management goals if animal movement is not considered. In populations with emigration and immigration, lethal control may induce compensatory immigration, if the source of attraction remains unchanged. Within the Columbia River Basin (Washington, U.S.A.), avian predators forage at dams because dams tend to reduce rates of emigration of juvenile salmonids (Oncorhynchus spp.), artificially concentrating these prey. We used differences in fatty acid profiles between Caspian Terns (Hydroprogne caspia) at coastal and inland breeding colonies and terns culled by a lethal control program at a mid‐Columbia River dam to infer dispersal patterns. We modeled the rate of loss of fatty acid biomarkers, which are fatty acids that can be traced to a single prey species or groups of species, to infer whether and when terns foraging at dams had emigrated from the coast. Nonmetric multidimensional scaling showed that coastal terns had high levels of C20 and C22 monounsaturated fatty acids, whereas fatty acids of inland breeders were high in C18:3n3, C20:4n6, and C22:5n3. Models of the rate of loss of fatty acid showed that approximately 60% of the terns collected at Rock Island Dam were unlikely to have bred successfully at local (inland) sites, suggesting that terns foraging at dams come from an extensive area. Fatty acid biomarkers may provide accurate information about patterns of dispersal in animal populations and may be extremely valuable in cases where populations differ demonstrably in prey base.  相似文献   
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Abstract: Community‐based natural resource conservation programs in developing nations face many implementation challenges underpinned by social‐psychological mechanisms. One challenge is garnering local support in an economically and socially sustainable fashion despite economic hardship and historical alienation from local resources. Unfortunately, conservationists' limited understanding of the social‐psychological mechanisms underlying participatory conservation impedes the search for appropriate solutions. We address this issue by revealing key underlying social‐psychological mechanisms of participatory conservation. Different administrative designs create social atmospheres that differentially affect endorsement of conservation goals. Certain forms of endorsement may be less effective motivators and less economically and socially sustainable than others. From a literature review we found that conservation initiatives endorsed primarily for nonautonomous instrumental reasons, such as to avoid economic fines or to secure economic rewards, are less motivating than those endorsed for autonomous reasons, such as for the opportunity for personal expression and growth. We suggest that successful participatory programs promote autonomous endorsement of conservation through an administrative framework of autonomy support—free and open democratic participation in management, substantive recognition and inclusion of local stakeholder identity, and respectful, noncoercive social interaction. This framework of the autonomy‐supportive environment (self‐determination theory) has important implications for future research into program design and incentive‐based conservation and identifies a testable social‐psychological theory of conservancy motivation.  相似文献   
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A comprehensive evaluation of the Nova Scotia graduated licensing program was conducted. This program was implemented on October 1, 1994 and applies to all novice drivers, regardless of age. It spans 2 1/2 years in two stages: a 6-month learner phase, followed by a 24-month newly licensed driver phase. During both phases several driving restrictions apply, most notably a requirement for adult supervision at all times in the learner phase and a night driving restriction from midnight to 5 a.m. in the newly licensed driver phase. The evaluation of this program used a series of increasingly refined analyses that controlled for the influence of other explanatory variables. All the analyses showed that the graduated licensing program in Nova Scotia was associated with a significant reduction in crashes. For drivers age 16, there was a 24 percent decrease in total crashes during the first full year of the program and a 37 percent reduction during the first 3 years of the program. Comparable decreases occurred in injury crashes. Improvements also were observed for all novice drivers, not just those who are young - there was a 19 percent decrease in the crash rate for all novice drivers. Comparisons with results from other graduated licensing programs indicate the Nova Scotia program has been more effective than others in reducing crashes.  相似文献   
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Abstract: New species conservation strategies, including the EDGE of Existence (EDGE) program, have expanded threatened species assessments by integrating information about species' phylogenetic distinctiveness. Distinctiveness has been measured through simple scores that assign shared credit among species for evolutionary heritage represented by the deeper phylogenetic branches. A species with a high score combined with a high extinction probability receives high priority for conservation efforts. Simple hypothetical scenarios for phylogenetic trees and extinction probabilities demonstrate how such scoring approaches can provide inefficient priorities for conservation. An existing probabilistic framework derived from the phylogenetic diversity measure (PD) properly captures the idea of shared responsibility for the persistence of evolutionary history. It avoids static scores, takes into account the status of close relatives through their extinction probabilities, and allows for the necessary updating of priorities in light of changes in species threat status. A hypothetical phylogenetic tree illustrates how changes in extinction probabilities of one or more species translate into changes in expected PD. The probabilistic PD framework provided a range of strategies that moved beyond expected PD to better consider worst‐case PD losses. In another example, risk aversion gave higher priority to a conservation program that provided a smaller, but less risky, gain in expected PD. The EDGE program could continue to promote a list of top species conservation priorities through application of probabilistic PD and simple estimates of current extinction probability. The list might be a dynamic one, with all the priority scores updated as extinction probabilities change. Results of recent studies suggest that estimation of extinction probabilities derived from the red list criteria linked to changes in species range sizes may provide estimated probabilities for many different species. Probabilistic PD provides a framework for single‐species assessment that is well‐integrated with a broader measurement of impacts on PD owing to climate change and other factors.  相似文献   
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