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1.
From Red Lists to Species of Conservation Concern   总被引:3,自引:0,他引:3  
Abstract:  National red lists of threatened animal and plant species prepared according to the criteria of the World Conservation Union (IUCN) adequately reflect the extinction risk of species within a country but cannot be used directly to set conservation priorities. In particular, the significance of national populations for the conservation of the species as a whole is not taken into account. We present a procedure that can be used to assess national responsibility based on the national red-list status of a species, the international importance of the national population, and the species' "historical rarity" status. We distinguished five responsibility classes for breeding birds: B1, threatened species with internationally important populations in Switzerland; B2, threatened species with internationally less important populations; B3, nonthreatened species with internationally important populations; B4, nonthreatened species with internationally less important populations; and B5, species that have never been common in Switzerland. Two responsibility classes were distinguished for birds occurring in Switzerland as visitors: G1, species with large concentrations in Switzerland and an unfavorable conservation status in Europe, and G2, species with large concentrations in Switzerland and a favorable conservation status in Europe. Two additional classes (G3 and G4) for visiting species occurring in internationally less important numbers are possible but were not analyzed in detail. Responsibility classes B1, B2, B3, G1, and G2 were defined as species of national conservation concern. We developed the method for birds in Switzerland, but it can be used in other countries and for other taxonomic groups as well. It is particularly suitable where national red lists are established according to IUCN guidelines.  相似文献   

2.
Abstract:  A World Conservation Union (IUCN) regional red list is an objective assessment of regional extinction risk and is not the same as a list of conservation priority species. Recent research reveals the widespread, but incorrect, assumption that IUCN Red List categories represent a hierarchical list of priorities for conservation action. We developed a simple eight-step priority-setting process and applied it to the conservation of bees in Ireland. Our model is based on the national red list but also considers the global significance of the national population; the conservation status at global, continental, and regional levels; key biological, economic, and societal factors; and is compatible with existing conservation agreements and legislation. Throughout Ireland, almost one-third of the bee fauna is threatened (30 of 100 species), but our methodology resulted in a reduced list of only 17 priority species. We did not use the priority species list to broadly categorize species to the conservation action required; instead, we indicated the individual action required for all threatened, near-threatened, and data-deficient species on the national red list based on the IUCN's conservation-actions template file. Priority species lists will strongly influence prioritization of conservation actions at national levels, but action should not be exclusive to listed species. In addition, all species on this list will not necessarily require immediate action. Our method is transparent, reproducible, and readily applicable to other taxa and regions.  相似文献   

3.
Abstract: Conservation funds are grossly inadequate to address the plight of threatened species. Government and conservation organizations faced with the task of conserving threatened species desperately need simple strategies for allocating limited resources. The academic literature dedicated to systematic priority setting usually recommends ranking species on several criteria, including level of endangerment and metrics of species value such as evolutionary distinctiveness, ecological importance, and social significance. These approaches ignore 2 crucial factors: the cost of management and the likelihood that the management will succeed. These oversights will result in misallocation of scarce conservation resources and possibly unnecessary losses. We devised a project prioritization protocol (PPP) to optimize resource allocation among New Zealand's threatened‐species projects, where costs, benefits (including species values), and the likelihood of management success were considered simultaneously. We compared the number of species managed and the expected benefits gained with 5 prioritization criteria: PPP with weightings based on species value; PPP with species weighted equally; management costs; species value; and threat status. We found that the rational use of cost and success information substantially increased the number of species managed, and prioritizing management projects according to species value or threat status in isolation was inefficient and resulted in fewer species managed. In addition, we found a clear trade‐off between funding management of a greater number of the most cost‐efficient and least risky projects and funding fewer projects to manage the species of higher value. Specifically, 11 of 32 species projects could be funded if projects were weighted by species value compared with 16 projects if projects were not weighted. This highlights the value of a transparent decision‐making process, which enables a careful consideration of trade‐offs. The use of PPP can substantially improve conservation outcomes for threatened species by increasing efficiency and ensuring transparency of management decisions.  相似文献   

4.
Utility of Mitochondrial DNA Barcodes in Species Conservation   总被引:9,自引:0,他引:9  
Abstract:  Molecular tools are a standard part of many conservation studies and can be informative at many different levels of analysis, although there are inherent limitations and strengths of different genes or parts of genes to inform specific questions. Animal DNA barcodes, 600- to 800-base-pair segments of the mitochondrial gene cytochrome oxidase I, have been proposed as a means to quantify global biodiversity. Although mitochondrial (mt) DNA has a long history of use at the species level, recent analyses suggest that the use of a single gene, particularly mitochondrial, is unlikely to yield data that are balanced, universally acceptable, or sufficient in taxonomic scope to recognize many species lineages. Mitochondrial and nuclear genomes have different patterns of evolution and modes of inheritance, which can result in very different assessments of biodiversity. The ramifications of choosing a particular definition of species (species concept) need to be carefully considered because current efforts have designated DNA barcodes as the universal species concept without demonstrating its superiority over preexisting concepts. The results of such a barcoding paradigm may include a failure to recognize significant portions of biodiversity or nuclear/mitochondrial mixed lineages and could spuriously focus conservation resources on populations with relatively minor mtDNA divergence. DNA barcodes are most likely to provide potentially useful information for groups that are already well studied, and such taxa do not constitute the majority of biodiversity or those in most need of research attention. DNA barcode-length sequences are an important source of data but, when used alone or out of context, may offer only a fraction of the information needed to characterize species while taking resources from broader studies that could produce information essential to robust and informed conservation decisions.  相似文献   

5.
Abstract:  Analysis of large-scale biodiversity patterns can uncover general relationships and problems that need to be taken into account when conservation strategies are developed. Nevertheless, these large-scale patterns need to be supplemented with information from local studies that can identify specific problems and determine how the land can be divided between conservation and development interests. I analyzed biodiversity patterns at three different scales to show how various scales of research contributed to conservation planning. A gap analysis for all of sub-Saharan Africa revealed that the network of wildlife reserves provides insufficient protection of narrowly endemic and threatened species, mainly because such species are aggregated in certain areas with dense human populations. A more fine-grained analysis of the distribution of forest birds of eastern Africa generally confirmed the results obtained with coarse-scale data and added precision by identifying forest tracts where conservation actions should be concentrated. Detailed local distribution data for one of the prioritized areas, the Uluguru Mountains in Tanzania, suggest that the actions to halt the loss of biodiversity should be concentrated in the submontane zone, immediately adjacent to densely populated areas. To achieve conservation on the ground, these general planning tools must be supplemented with other kinds of research concerning land-use and local knowledge and with approaches that promote more sustainable development. Different types of institutions will be needed for these different tasks, but it is essential that researchers maintain a dialogue with planners in this area .  相似文献   

6.
Abstract:  Public preferences are likely to play an important role in prioritizing species at risk for conservation. We conducted a survey of British Columbians (Canada) ( n = 555 , r = 73 % ) to examine how the public ranks a species' attributes (rather than named species) with respect to conservation priority. Endemism, defined as species only or mainly occurring in British Columbia or species occurring in British Columbia and nowhere else in Canada, was considered the most important among the measured attributes. This preference was strongest among men and among respondents who had completed postsecondary education. The preference for endemism is generally consistent with science-based federal listings of British Columbian species. This congruence between listing and public opinion is welcome if such congruence is considered important. We suggest that investigating how much the public values species' attributes, as opposed to named species, provides a more efficient way of incorporating public opinion into policies on species at risk, especially if large numbers of species must be ranked for conservation priority .  相似文献   

7.
Abstract:  We developed a method with which to analyze a specie's response to chronic anthropogenic disturbance (CAD). We regressed density of individuals on the intensity of 3 disturbance agents (human activities, raising livestock, and land degradation) along CAD gradients to determine how much CAD is experienced by a species; whether species are ruderal (achieving maximum densities in disturbed sites); whether density declines as a result of CAD; which disturbance agents are responsible for this reduction; and the number of populations that decline as a result of CAD. We tested the method on 9 threatened Mammillaria species (Cactaceae). Seven species were ruderal. In 4 species, actual disturbance surpassed the CAD intensity in which plants achieved their maximum densities; thus, the density of those 4 species appeared to be declining. For 7 species, some populations were threatened by human activities or livestock, whereas others were favored by them. Land degradation negatively affected all species. Our results allowed us to distinguish 4 groups of species that had similar responses and thus may require different forms of management. Our method provided an estimation of the growth rate (λ) of the studied populations that was significantly correlated with λs obtained from demographic studies. The size structures of populations were consistent with the predictions of the analysis, which suggests our results are consistent and reliable. Disturbance–response analysis provides a basis for management in heavily populated areas, where conservation must be achieved along with development activities that cause CAD. The method provides readily interpretable information, which facilitates participative decision making; the data are rapidly generated, which makes it appropriate when results are required promptly or for assessment of large numbers of species; and it provides a comprehensive perception of how threatened species behave in the real world.  相似文献   

8.
9.
Status of Species Conservation Banking in the United States   总被引:1,自引:0,他引:1  
Abstract:  Receiving financial gains for protecting habitat may be necessary to proactively protect endangered species in the United States. Species conservation banking, the creation and trading of "credits" that represent biodiversity values on private land, is nearly a decade old. We detail the biological, financial, and political experience of conservation banking in the United States. We contacted agencies, nongovernmental organizations, and bank owners and compiled comprehensive accounts of the experiences of current banks. There are 76 properties identified as conservation banks in the United States, but only 35 of these are established under a conservation banking agreement approved by the U.S. Fish and Wildlife Service (USFWS). The 35 official conservation banks cumulatively cover 15,987 ha and shelter a range of biodiversity, including more than 22 species listed under the U.S. Endangered Species Act. Financial motives drove the establishment of 91% of conservation banks, and the majority of for-profit banks are breaking even or making money. With credit prices ranging from $3,000 to $125,000/0.41 ha (1 acre), banking agreements offer financial incentives that compete with development and provide a business-based argument for conserving habitat. Although the bureaucracy of establishing an agreement with the USFWS was burdensome, 63% of bank owners reported they would set up another agreement given the appropriate opportunity. Increasing information sharing, decreasing the time to establish agreements (currently averaging 2.18 years), and reducing bureaucratic challenges can further increase the amount of private property voluntarily committed to banking. Although many ecological uncertainties remain, conservation banking offers at least a partial solution to the conservation versus development conflict over biodiversity.  相似文献   

10.
Abstract:  Developed nations intervened in conservation policy across Africa during the 20th century to address needs to protect species and biodiversity that were based on their own perceptions and priorities. In the 21st century, conservationists in Africa have revised these perceptions and begun the process of identifying conservation priorities from an African perspective and in consideration of Africans' priorities. Although foreign conservation interveners struggled to identify mechanisms to which local people would respond, African conservationists are now demonstrating how to integrate the continent's unique socioeconomic circumstances into efforts to protect biodiversity. In Africa effective conservation policy must include the generation of wealth, reduction of disease and hunger, and support of traditional land-use practices.  相似文献   

11.
Abstract:  The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species.  相似文献   

12.
Abstract:  It has been suggested that transgenics and vertebrate cloning have a role to play in conservation. Now is the time to evaluate their risks and benefits, before these technologies are widely implemented in our field. Direct risks of transgenics include escape and introgression of transgenes into wild populations; weedy invasion by transgenic organisms; toxicity or pathogenicity of engineered organisms and their products; and human error in the field testing and tracking of transgenic organisms. Indirect risks include environmental effects of increased herbicide use; the danger that engineered organisms may aid the development of bioweapons; the likelihood that gene patenting will lead to the privatization of natural resources; and the diversion of support from less glamorous forms of conservation. Formal risk assessments are commonly used to evaluate transgenic procedures, but our incomplete understanding of both ecosystem processes and the action of transgenes renders most of these assessments scientifically and socially unjustified. Nevertheless, a few, low-risk applications of transgenics may be possible: for example, "super-sterile" ornamental cultivars. Vertebrate cloning poses little risk to the environment, but it can consume scarce conservation resources, and its chances of success in preserving species seem poor. To date, the conservation benefits of transgenics and vertebrate cloning remain entirely theoretical, but many of the risks are known and documented. Conservation biologists should devote their research and energies to the established methods of conservation, none of which require transgenics or vertebrate cloning.  相似文献   

13.
Use of Substitute Species in Conservation Biology   总被引:2,自引:0,他引:2  
Abstract:  In conservation biology, researchers often want to study the reasons why an endangered population is faring poorly but are unable to study it directly for logistical or political reasons. Instead they study a species that substitutes for the one of concern in the hope that it will cast light on the conservation problem. Here we outline the assumptions underlying this approach. Substitutes can be different populations or species and may be chosen because they are similar biologically to the target or representatives of a constellation of species of which the target is one. They also may be used to develop a predictive model to which the conservation target can be related. For substitutes to be appropriate, they should share the same key ecological or behavioral traits that make the target sensitive to environmental disturbance and the relationship between population vital rates and level of disturbance should match that of the target. These conditions are unlikely to pertain in most circumstances and the use of substitute species to predict endangered populations' responses to disturbance is questionable.  相似文献   

14.
Abstract:  Species conservation status is commonly used as a broad-scale indicator of the state of biological diversity. To learn about its value for tracking trends, we examined provincial lists of terrestrial vertebrate species and subspecies at risk in British Columbia, Canada, for 1992 and 2002 to see whether changes in these lists reflected changes in the status of the taxa they represent. Examination of the case histories of individual species and subspecies showed that 65% of additions and deletions to the British Columbia Red List were the result of improvement in knowledge of species status, changes in assessment procedures, and refinements in taxonomy rather than actual changes in a species' status. Comparison to an alternate set of rank scores provided by NatureServe for taxa that appeared on both 1992 and 2002 British Columbia Red Lists revealed changes in status that were not reflected by movement from the list. Estimates of historical conservation status for species on the 1992 British Columbia Red List demonstrated ambiguity around the natural baseline with regard to tracking changes in list composition over time. We discourage the continued use of indicators based solely on conservation status as a means of tracking biodiversity. Instead we recommend advancing strategic indicators around species at risk based on long-term monitoring data, deliberate and explicitly stated baselines, and consistent methods of conservation ranking.  相似文献   

15.
Guidelines for Systematic Review in Conservation and Environmental Management   总被引:10,自引:0,他引:10  
Abstract:  An increasing number of applied disciplines are utilizing evidence-based frameworks to review and disseminate the effectiveness of management and policy interventions. The rationale is that increased accessibility of the best available evidence will provide a more efficient and less biased platform for decision making. We argue that there are significant benefits for conservation in using such a framework, but the scientific community needs to undertake and disseminate more systematic reviews before the full benefit can be realized. We devised a set of guidelines for undertaking formalized systematic review, based on a health services model. The guideline stages include planning and conducting a review, including protocol formation, search strategy, data inclusion, data extraction, and analysis. Review dissemination is addressed in terms of current developments and future plans for a Web-based open-access library. By the use of case studies we highlight critical modifications to guidelines for protocol formulation, data-quality assessment, data extraction, and data synthesis for conservation and environmental management. Ecological data presented significant but soluble challenges for the systematic review process, particularly in terms of the quantity, accessibility, and diverse quality of available data. In the field of conservation and environmental management there needs to be further engagement of scientists and practitioners to develop and take ownership of an evidence-based framework.  相似文献   

16.
Protected Areas and Prospects for Endangered Species Conservation in Canada   总被引:3,自引:0,他引:3  
Abstract:  Reserve networks figure prominently in conservation strategies that aim to reduce extinction rates. We tested the effectiveness of the current reserve network at protecting species at risk in Canada, where relatively extensive wilderness areas remain. We compared numbers of terrestrial species at risk included in existing reserves to randomly generated networks with the same total area and number of reserves. Existing reserve networks rarely performed better than randomly selected areas and several included fewer endangered species than expected by chance, particularly in the most biologically imperiled regions. The extent of protected area and density of species at risk were unrelated at either broad (countrywide) or finer spatial scales (50 × 50 km grids), although there was a tendency for the most threatened regions of the country to have few or no protected areas (1.5% of areas with >30 endangered species were in reserves). Although reserves will play a useful role in conserving endangered species that occur within them, reducing extinction rates in a region with much of the world's remaining wilderness will require integrating conservation strategies with agricultural and urban land-use plans outside formally protected areas.  相似文献   

17.
Abstract:  Marine protected areas, and other fishery management systems that impart partial or total protection from fishing, are increasingly advocated as an essential management tool to ensure the sustainable use of marine resources. Beneficial effects for fish species are well documented for tropical and reef systems, but the effects of marine protected areas remain largely untested in temperate waters. We compared trends in sport-fishing catches of nine fish species in an area influenced by a large (500-km2) towed-fishing-gear restriction zone and in adjacent areas under conventional fishery management controls. Over the period 1973–2002 the mean reported weight of above-average-sized (trophy) fish of species with early age at maturity and limited home range was greatest within the area influenced by the fishing-gear restriction zone. The reported weight of trophy fish of species that mature early also declined less and more slowly over time within the area influenced by the fishing-gear restriction zone. Importantly, the mean reported weight of trophy fish of species that mature late and those that undertake extensive spatial movements declined at the same rate in all areas. Hence these species are likely to require protected areas >500 km2 for effective protection. Our results also indicated that fish species with a localized distribution or high site fidelity may require additional protection from sport fishing to prevent declines in the number or size of fish within the local population.  相似文献   

18.
Abstract:  Traditional ecological knowledge can be highly informative and integrated with complementary scientific knowledge to improve species management. This is especially true for abundant species with which indigenous peoples have frequent interactions (e.g., through harvest), but has been studied less frequently in isolated or declining species. We examined Maori traditional ecological knowledge of tuatara ( Sphenodon spp., reptiles that resemble lizards but are the last living representatives of the order Sphenodontia) through semidirected interviews of elders of Te Atiawa, Ngati Koata, and Ngati Wai Iwi (similar to tribes), the guardians of several islands currently inhabited by tuatara. Maori are indigenous to New Zealand, having settled 800 to 1000 years ago. Tuatara are endemic to New Zealand, have declined in numbers since human settlement, and are now restricted to 37 offshore islands. The detail and volume of tuatara traditional ecological knowledge were less than that recorded in studies of more abundant or accessible species. In addition, traditional knowledge of the cultural significance of tuatara was more common and detailed among the elders than traditional knowledge of tuatara biology or ecology. The traditional knowledge collected, however, provided the first evidence of seven former sites of tuatara occupation, suggested five additional sites tuatara may currently occupy, contained novel hypotheses for scientific testing, and described tuatara cultural roles that have not been reported previously. We conclude that, in at least some cases, traditional ecological knowledge may persist as species decline and may serve as a valuable source of ecological information for conservation .  相似文献   

19.
Conservation Value of Multiple-Use Areas in East Africa   总被引:3,自引:0,他引:3  
Abstract:  Despite wide agreement that strictly protected areas (World Conservation Union categories I–III) are the best strategy for conserving biodiversity, they are limited in extent and exclude many species of key conservation importance. In contrast, multiple-use management areas (categories IV–VI), comprising >60% of the world's protected-area network, are often considered of little value to biodiversity conservation, particularly in Africa, where they typically contain few charismatic large mammals. We sampled small mammals, amphibians, birds, butterflies, and trees at 41 sites along a four-step gradient of increasing human activity and decreasing conservation protection, from a well-protected Tanzanian national park to nonintensive agricultural land. Although preliminary, our results indicate that species richness of these five taxa did not decline along this gradient, but different management areas, occupying areas of largely similar habitat, hosted distinct communities of each taxon. Differences in species composition in the absence of manifest differences in species richness highlight the importance of developing landscape-scale conservation strategies and the danger of using either a limited suite of indicator taxa or umbrella species as surrogates for biodiversity. Although strictly protected areas perform a unique and vital conservation service in East Africa by protecting large mammals, areas that allow varied resource extraction activities still possess vital and complementary conservation value.  相似文献   

20.
Abstract:  We assessed the extinction risks of Malagasy amphibians by evaluating their distribution, occurrence in protected areas, population trends, habitat quality, and prevalence in commercial trade. We estimated and mapped the distribution of each of the 220 described Malagasy species and applied, for the first time, the IUCN Red List categories and criteria to all species described at the time of the assessment. Nine species were categorized as critically endangered, 21 as endangered, and 25 as vulnerable. The most threatened species occur on the High Plateau and/or have been subjected to overcollection for the pet trade, but restricted extent of occurrence and ongoing habitat destruction were identified as the most important factors influencing extinction threats. The two areas with the majority of threatened species were the northern Tsaratanana-Marojejy-Masoala highlands and the southeastern Anosy Mountains. The current system of protected areas includes 82% of the threatened amphibian species. Of the critically endangered species, 6 did not occur in any protected area. For conservation of these species we recommend the creation of a reserve for the species of the Mantella aurantiaca group, the inclusion of two Scaphiophryne species in the Convention on the International Trade in Endangered Species Appendix II, and the suspension of commercial collecting for Mantella cowani . Field surveys during the last 15 years reveal no pervasive extinction of Malagasy amphibians resulting from disease or other agents, as has been reported in some other areas of the world.  相似文献   

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