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501.
Taxonomy is the foundation of biodiversity science because it furthers discovery of new species. Globally, there have never been so many people involved in naming species new to science. The number of new marine species described per decade has never been greater. Nevertheless, it is estimated that tens of thousands of marine species, and hundreds of thousands of terrestrial species, are yet to be discovered; many of which may already be in specimen collections. However, naming species is only a first step in documenting knowledge about their biology, biogeography, and ecology. Considering the threats to biodiversity, new knowledge of existing species and discovery of undescribed species and their subsequent study are urgently required. To accelerate this research, we recommend, and cite examples of, more and better communication: use of collaborative online databases; easier access to knowledge and specimens; production of taxonomic revisions and species identification guides; engagement of nonspecialists; and international collaboration. “Data‐sharing” should be abandoned in favor of mandated data publication by the conservation science community. Such a step requires support from peer reviewers, editors, journals, and conservation organizations. Online data publication infrastructures (e.g., Global Biodiversity Information Facility, Ocean Biogeographic Information System) illustrate gaps in biodiversity sampling and may provide common ground for long‐term international collaboration between scientists and conservation organizations.  相似文献   
502.
Forests cover approximately one‐third of Central Europe. Oak (Quercus) and European beech (Fagus sylvatica) are considered the natural dominants at low and middle elevations, respectively. Many coniferous forests (especially of Picea abies) occur primarily at midelevations, but these are thought to have resulted from forestry plantations planted over the past 200 years. Nature conservation and forestry policy seek to promote broadleaved trees over conifers. However, there are discrepancies between conservation guidelines (included in Natura 2000) and historical and palaeoecological data with regard to the distribution of conifers. Our aim was to bring new evidence to the debate on the conservation of conifers versus broadleaved trees at midelevations in Central Europe. We created a vegetation and land‐cover model based on pollen data for a highland area of 11,300 km2 in the Czech Republic and assessed tree species composition in the forests before the onset of modern forestry based on 18th‐century archival sources. Conifers dominated the study region throughout the entire Holocene (approximately 40–60% of the area). Broadleaved trees were present in a much smaller area than envisaged by current ideas of natural vegetation. Rather than casting doubt on the principles of Central European nature conservation in general, our results highlight the necessity of detailed regional investigations and the importance of historical data in challenging established notions on the natural distribution of tree species.  相似文献   
503.
Mitigation translocation of nuisance animals is a commonly used management practice aimed at resolution of human–animal conflict by removal and release of an individual animal. Long considered a reasonable undertaking, especially by the general public, it is now known that translocated subjects are negatively affected by the practice. Mitigation translocation is typically undertaken with individual adult organisms and has a much lower success rate than the more widely practiced conservation translocation of threatened and endangered species. Nonetheless, the public and many conservation practitioners believe that because population‐level conservation translocations have been successful that mitigation translocation can be satisfactorily applied to a wide variety of human‐wildlife conflict situations. We reviewed mitigation translocations of reptiles, including our own work with 3 long‐lived species (Gila monsters [Heloderma suspectum], Sonoran desert tortoises [Gopherus morafkai], and western diamond‐backed rattlesnakes [Crotalus atrox]). Overall, mitigation translocation had a low success rate when judged either by effects on individuals (in all studies reviewed they exhibited increased movement or increased mortality) or by the success of the resolution of the human–animal conflict (translocated individuals often returned to the capture site). Careful planning and identification of knowledge gaps are critical to increasing success rates in mitigation translocations in the face of increasing pressure to find solutions for species threatened by diverse anthropogenic factors, including climate change and exurban and energy development. Problemas con la Mitigación por Traslocación de Herpetofauna  相似文献   
504.
Adaptive management implies a continuous knowledge‐based decision‐making process in conservation. Yet, the coupling of scientific monitoring and management frameworks remains rare in practice because formal and informal communication pathways are lacking. We examined 4 cases in Micronesia where conservation practitioners are using new knowledge in the form of monitoring data to advance marine conservation. These cases were drawn from projects in Micronesia Challenge jurisdictions that received funding for coupled monitoring‐to‐management frameworks and encompassed all segments of adaptive management. Monitoring in Helen Reef, Republic of Palau, was catalyzed by coral bleaching and revealed evidence of overfishing that led to increased enforcement and outreach. In Nimpal Channel, Yap, Federated States of Micronesia (FSM), monitoring the recovery of marine food resources after customary restrictions were put in place led to new, more effective enforcement approaches. Monitoring in Laolao Bay, Saipan, Commonwealth of the Northern Mariana Islands, was catalyzed by observable sediment loads from poor land‐use practices and resulted in actions that reduced land‐based threats, particularly littering and illegal burning, and revealed additional threats from overfishing. Pohnpei (FSM) began monitoring after observed declines in grouper spawning aggregations. This data led to adjusting marine conservation area boundaries and implementing market‐based size class restrictions. Two themes emerged from these cases. First, in each case monitoring was conducted in a manner relevant to the social and ecological systems and integrated into the decision‐making process. Second, conservation practitioners and scientists in these cases integrated culturally appropriate stakeholder engagement throughout all phases of the adaptive management cycle. More broadly, our study suggests, when describing adaptive management, providing more details on how monitoring and management activities are linked at similar spatial scales and across similar time frames can enhance the application of knowledge.  相似文献   
505.
We used linear and multivariate models to examine the associations between geography, biodiversity, per capita economic output, national spending on conservation, governance, and cultural traits in 55 countries. Cultural traits and social metrics of modernization correlated positively with national spending on conservation. The global distribution of this spending culture was poorly aligned with the distribution of biodiversity. Specifically, biodiversity was greater in the tropics where cultures tended to spend relatively less on conservation and tended to have higher collectivism, formalized and hierarchical leadership, and weaker governance. Consequently, nations lacking social traits frequently associated with modernization, environmentalism, and conservation spending have the largest component of Earth's biodiversity. This has significant implications for setting policies and priorities for resource management given that biological diversity is rapidly disappearing and cultural traits change slowly. Therefore, we suggest natural resource management adapt to and use characteristics of existing social organization rather than wait for or promote social values associated with conservation spending. Supporting biocultural traditions, engaging leaders to increase conservation commitments, cross‐national efforts that complement attributes of cultures, and avoiding interference with nature may work best to conserve nature in collective and hierarchical societies. Spending in modernized nations may be a symbolic response to a symptom of economic development and environmental degradation, and here conservation actions need to ensure that biodiversity is not being lost.  相似文献   
506.
The nonsteroidal anti‐inflammatory drug (NSAID) diclofenac is highly toxic to Gyps vultures, and its recent widespread use in South Asia caused catastrophic declines in at least 3 scavenging raptors. The manufacture of veterinary formulations of diclofenac has since been banned across the region with mixed success. However, at least 12 other NSAIDs are available for veterinary use in South Asia. Aceclofenac is one of these compounds, and it is known to metabolize into diclofenac in some mammal species. The metabolic pathway of aceclofenac in cattle, the primary food of vultures in South Asia, is unknown. We gave 6 cattle the recommended dose of aceclofenac (2 mg/kg), collected blood thereafter at intervals for up to 12 h, and used liquid chromatography with mass spectrometry in a pharmacokinetic analysis of aceclofenac and diclofenac in the plasma. Nearly all the aceclofenac administered to the cattle was very rapidly metabolized into diclofenac. At 2 h, half the aceclofenac had been converted into diclofenac, and at 12 h four‐fifths of the aceclofenac had been converted into diclofenac. Therefore, administering aceclofenac to livestock poses the same risk to vultures as administering diclofenac to livestock. This, coupled with the risk that aceclofenac may replace diclofenac in the veterinary market, points to the need for an immediate ban on all aceclofenac formulations that can be used to treat livestock. Without such a ban, the recovery of vultures across South Asia will not be successful.  相似文献   
507.
508.
Given that funds for biodiversity conservation are limited, there is a need to understand people's preferences for its different components. To date, such preferences have largely been measured in monetary terms. However, how people value biodiversity may differ from economic theory, and there is little consensus over whether monetary metrics are always appropriate or the degree to which other methods offer alternative and complementary perspectives on value. We used a choice experiment to compare monetary amounts recreational visitors to urban green spaces were willing to pay for biodiversity enhancement (increases in species richness for birds, plants, and aquatic macroinvertebrates) with self‐reported psychological gains in well‐being derived from visiting the same sites. Willingness‐to‐pay (WTP) estimates were significant and positive, and respondents reported high gains in well‐being across 3 axes derived from environmental psychology theories (reflection, attachment, continuity with past). The 2 metrics were broadly congruent. Participants with above‐median self‐reported well‐being scores were willing to pay significantly higher amounts for enhancing species richness than those with below‐median scores, regardless of taxon. The socio‐economic and demographic background of participants played little role in determining either their well‐being or the probability of choosing a paying option within the choice experiment. Site‐level environmental characteristics were only somewhat related to WTP, but showed strong associations with self‐reported well‐being. Both approaches are likely to reflect a combination of the environmental properties of a site and unobserved individual preference heterogeneity for the natural world. Our results suggest that either metric will deliver mutually consistent results in an assessment of environmental preferences, although which approach is preferable depends on why one wishes to measure values for the natural world. Preferencias de Cuantificación para el Mundo Natural Usando Estudios de Valor Monetario y No Monetario.  相似文献   
509.
Oyster reefs form over extensive areas and the diversity and productivity of sheltered coasts depend on them. Due to the relatively recent population growth of coastal settlements in Australia, we were able to evaluate the collapse and extirpation of native oyster reefs (Ostrea angasi) over the course of a commercial fishery. We used historical records to quantify commercial catch of O. angasi in southern Australia from early colonization, around 1836, to some of the last recorded catches in 1944 and used our estimates of catch and effort to map their past distribution and assess oyster abundance over 180 years. Significant declines in catch and effort occurred from 1886 to 1946 and no native oyster reefs occur today, but historically oyster reefs extended across more than 1,500 km of coastline. That oyster reefs were characteristic of much of the coastline of South Australia from 1836 to 1910 appears not to be known because there is no contemporary consideration of their ecological and economic value. Based on the concept of a shifted baseline, we consider this contemporary state to reflect a collective, intergenerational amnesia. Our model of generational amnesia accounts for differences in intergenerational expectations of food, economic value, and ecosystem services of nearshore areas. An ecological system that once surrounded much of the coast and possibly the past presence of oyster reefs altogether may be forgotten and could not only undermine progress towards their recovery, but also reduce our expectations of these coastal ecosystems. La Pérdida de una Línea de Base Ecológica por Medio de la Erradicación de Arrecifes de Ostión de los Ecosistemas Costeros y la Memoria Humana  相似文献   
510.
Territorial user rights for fisheries are being promoted to enhance the sustainability of small‐scale fisheries. Using Chile as a case study, we designed a market‐based program aimed at improving fishers’ livelihoods while incentivizing the establishment and enforcement of no‐take areas within areas managed with territorial user right regimes. Building on explicit enabling conditions (i.e., high levels of governance, participation, and empowerment), we used a place‐based, human‐centered approach to design a program that will have the necessary support and buy‐in from local fishers to result in landscape‐scale biodiversity benefits. Transactional infrastructure must be complex enough to capture the biodiversity benefits being created, but simple enough so that the program can be scaled up and is attractive to potential financiers. Biodiversity benefits created must be commoditized, and desired behavioral changes must be verified within a transactional context. Demand must be generated for fisher‐created biodiversity benefits in order to attract financing and to scale the market model. Important design decisions around these 3 components—supply, transactional infrastructure, and demand—must be made based on local social‐ecological conditions. Our market model, which is being piloted in Chile, is a flexible foundation on which to base scalable opportunities to operationalize a scheme that incentivizes local, verifiable biodiversity benefits via conservation behaviors by fishers that could likely result in significant marine conservation gains and novel cross‐sector alliances. Incentivar la Conservación de la Biodiversidad con Comunidades de Pesca Artesanal por medio de Derechos de Uso Territorial y la Innovación de Modelos de Negocio  相似文献   
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