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The progressive decline in red squirrel (Sciurus vulgaris) numbers in Wales has led to conservation and reintroduction projects being established on the island of Anglesey. The recovery of the island’s remnant wild population was initially successful, however concern remained over potential loss of genetic diversity resulting from an observed demographic bottleneck. We used mitochondrial DNA (mtDNA) control region sequences and six microsatellite loci to assess current levels of genetic variation in the population. Samples were monomorphic for control region sequences and a historic specimen from the same area carrying a different haplotype demonstrated a loss of mtDNA diversity during the last 20 years. Inclusion of other Welsh haplotypes indicated phylogeographic structure in the region, in contrast to previous UK studies. Genotyping results showed allelic diversity and heterozygosity to be less than 50% of that recorded in other UK populations, with strong evidence for a recent genetic bottleneck. A parallel reintroduction programme on Anglesey included genetic analysis of individuals during the selection of captive breeding pairs. We present analysis of sequence and microsatellite data, and subsequent management decisions taken to maximise diversity in the founder and F1 generations. Population and Habitat Viability Analysis applied to both populations modelled future levels of heterozygosity and allelic diversity. Supplementation of the remnant and reintroduced populations with translocated squirrels was simulated as a potential management tool; results support use of this strategy to reduce loss of diversity and increase survival. The limitations of applying conservation genetic theory within small-scale management projects are discussed.  相似文献   

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While wild populations continue to decrease, the number of orphaned primates, sanctuaries, and attempts to reintroduce primates back to the natural environment are increasing. An umbrella organization called the Pan-African Sanctuary Alliance (PASA) was formed in 2000 and recently the IUCN Reintroduction Specialist Group developed a set of specific policy guidelines for primates (2002). Data presented in this report are based upon questionnaire responses by managers from 17 African facilities that have become members of PASA (membership in PASA is defined by attendance at an annual PASA workshop). These PASA facilities house over 500 great apes. (There may be other facilities not represented here simply because their managers did not attend a PASA workshop.) The majority of the apes arrived at the sanctuaries when they were less than 4 years old and half were confiscated. Over 40% were found awaiting sale, and 30% had been previously kept as pets. Common ailments upon arrival included internal parasites, behavioral abnormalities, and malnutrition; 20% of the total sanctuary population died prematurely. Most sanctuaries use a combination of enclosures surrounded by electric fencing and cages to accommodate the apes. Sanctuaries actively participate in conservation education, habitat protection, tourism, scientific data collection, local development, and reintroduction. The median total facility operating cost was 65,000 US dollars per annum. The median facility cost per ape was 2,222 US dollars per annum. Most funding comes from overseas nongovernmental agencies. Discussion focuses on evaluating the present status of sanctuaries, the problems facing them, and their potential role in African conservation issues.  相似文献   

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生物多样性资源:利用、保护与管理   总被引:11,自引:3,他引:11  
生物多样性在本质上是一种具有多重价值,高度综合的资源形式,是人类社会生存与发展的物质基础,在人类社会发展过程中,生物多样性资源利用与保护之间日益表现为彼此冲突的特征,但并非不可调和。本文认为,协调二者关系,实现生物多样性资源可持续利用和区域社会经济可持续发展的根本途径是生物多样性资源管理,它由主体层,客体层和目标层构成,应该具备主体多元化,参与的广泛性,过程的动态性与持续性,尺度性与地域性和公平性等基本特征,主体层是由以人为核心的各种组织形式构成的,是从社会经济系统中分化出来的一个职能层次;客体层也就是管理的对象层,是生物多样性资源系统和社会经济系统的耦合体,目标层包括生物多样性资源的可持续利用,生态文明的构建与发展和区域社会经济的可持续发展,生态文明是生物多样性资源可持续利用和区域社会可持续发展的根本保障,其中,主体层和客体层构成了生物多样性资源管理的实体部分,而目标层则是生物多样性资源管理的参照体系,生物多样性资源管理包括管理范围界定,问题辨识,目标确定,政策制定与方案运筹,实施,监测与评价,适应性调整6个基本步骤,是一个复杂的多层次动态反馈过程,这一过程中,科学研究发挥着非常重要的作用,因此应该在加强生物多样性科学研究的同时融合科学与管理的关系,使科学成果真正转化成效的管理行为。  相似文献   

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As defaunation spreads through the world, there is an urgent need for restoring ecological interactions, thus assuring ecosystem processes. Here, we define the new concept of credit of ecological interactions, as the number of interactions that can be restored in a focal area by species colonization or reintroduction. We also define rewiring time, as the time span until all the links that build the credit of ecological interactions of a focal area have become functional again. We expect that the credit will be gradually cashed following refaunation in rates that are proportional to (1) the abundance of the reintroduced species (that is expected to increase in time since release), (2) the abundance of the local species that interact with them, and (3) the traits of reintroduced species. We illustrated this approach using a theoretical model and an empirical case study where the credit of ecological interactions was estimated. This new conceptual framework is useful for setting reintroduction priorities and for evaluating the success of conservation initiatives that aim to restore ecosystem services.  相似文献   

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Thuriferous juniper is only found in isolated parts of the western Mediterranean: France (Alps, Pyrenees and Corsican highlands), Spain, Algeria and Morocco. These semi-arid mountain stands, where thuriferous juniper trees grow in low-density open woodland, are seriously endangered: (i) In the Atlas mountains, the thuriferous juniper stands are heavily degraded as a result of the intensive wood removal and livestock activity in these densely populated areas. This situation, which will soon become irreversible unless remedial measures are urgently taken, has produced impoverished soils and hillside instability while contributing to desertification. (ii) In Spain, although livestock activity and cultivation have strongly reduced areas occupied by Juniperus thurifera, stands are still numerous and, in some regions, show a good regeneration due to conservation measures. (iii) In France, the decline in human and livestock activities over recent decades has led to a recolonization of some of the Juniper stands by pines or oak. A forest management system that enables these original stands to survive and regenerate must be undertaken without delay. The dynamics of evolution of these stands is quite different north and south of the Mediterranean. In both cases, conservation measures are urgently required to protect or rehabilitate these original stands with floristic, ecological and socio-economic interest.  相似文献   

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Sensory‐based conservation harnesses species' natural communication and signalling behaviours to mitigate threats to wild populations. To evaluate this emerging field, we assess how sensory‐based manipulations, sensory mode, and target taxa affect success. To facilitate broader, cross‐species application of successful techniques, we test which behavioural and life‐history traits correlate with positive conservation outcomes. We focus on seabirds, one of the world's most rapidly declining groups, whose philopatry, activity patterns, foraging, mate choice, and parental care behaviours all involve reliance on, and therefore strong selection for, sophisticated sensory physiology and accurate assessment of intra‐ and inter‐species signals and cues in several sensory modes. We review the use of auditory, olfactory, and visual methods, especially for attracting seabirds to newly restored habitat or deterring birds from fishing boats and equipment. We found that more sensory‐based conservation has been attempted with Procellariiformes (tube‐nosed seabirds) and Charadriiformes (e.g. terns and gulls) than other orders, and that successful outcomes are more likely for Procellariiformes. Evolutionary and behavioural traits are likely to facilitate sensory‐based techniques, such as social attraction to suitable habitat, across seabird species. More broadly, successful application of sensory‐based conservation to other at‐risk animal groups is likely to be associated with these behavioural and life‐history traits: coloniality, philopatry, nocturnal, migratory, long‐distance foraging, parental care, and pair bonds/monogamy.  相似文献   

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  • 1 This review highlights the status of the European wild rabbit Oryctolagus cuniculus, which is threatened within its native range and yet is a highly successful colonizer across its worldwide, introduced range.
  • 2 The European wild rabbit is a keystone species in Iberia, and the survival of a range of threatened predator species, including the Iberian lynx Lynx pardinus and Spanish imperial eagle Aquila aldabertii, is dependent upon the restoration of rabbit populations. Although not native to the UK, the rabbit also performs significant ecosystem services for nationally rare UK species, by maintaining short sward heights in heathland and grassland ecosystems, and serving as a prey item for populations of predators.
  • 3 We identify the European wild rabbit as an excellent model to demonstrate the wide range of complex effects that an introduced mammalian species may exert on ecosystems to which it has been introduced. These effects include habitat degradation following overgrazing, competition with native mammals and facilitating meso‐predator release and hyperpredation.
  • 4 We also show that rabbit eradication from some sites may generate more problems than are solved because of the impacts of trophic cascades stemming from dependence on rabbits by native predator assemblages.
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The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human–carnivore conflict, which has led to long‐term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the ‘pre‐genomic era’ and the first insights of the ‘genomics era’. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large‐scale trends and patterns of genetic variation in European wolf populations, we conducted a meta‐analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south‐west (lowest genetic diversity) to north‐east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650?850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science‐based wolf conservation and management at regional and Europe‐wide scales.  相似文献   

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Forest conservation and environmental management in Nepal: a review   总被引:1,自引:0,他引:1  
This paper provides information on the status of forests and environmental problems related to forestry in Nepal. It aims to integrate the conservation and sustainable management of forests as a part of environmental planning. A critical review of the main environmental problems with prioritization within the forestry sector; thorough review of all forest related documents, strategies, development plans, programs, institutional arrangements, policies mentioned in the Master Plan for Forestry Sector Nepal of 1988, and other relevant documents; identification of major gaps and constraints of forestry policy and plans and current practices of forest conservation and management have been done. The decline in forestry resources in Nepal took place in the past due to lack of appropriate policy to guide the legal, institutional and operational development for the forestry sector. Forestry policy in Nepal, in the past, was shaped by political and economic motives rather than ecological considerations. Policy formulation mechanisms exist in Nepal; however, there is an excessive delay in translating policies into legislation and then into operational rules and administrative orders. There is a need to implement the international obligations by transforming them into regulations in order to make them legally binding. The data to be generated in the coming years in the areas of forestry at both national and international levels suggest that we should revise the research priorities and strategies. Research to add value to the forest resource products has yet been neglected. More attention is required on regular monitoring and evaluation of the projects. A thorough evaluation of the programs and planning for the forestry sector in Nepal is urgently required to update the progress and revise the programs.  相似文献   

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Application of habitat models for predicting expected local densities of Atlantic Salmon Salmo salar in healthy populations has been hampered by a lack of generality in their fit to data from different systems. It is believed that this problem results at least in part from difficulties of effectively integrating factors that act across a range of spatial and temporal scales. Here, as an aid to developing more robust modelling and sampling methodologies, a simple process‐based model for local‐scale dynamics of Atlantic salmon juveniles is developed from first principles by integrating contemporary understanding of self‐thinning, density‐dependent growth and dispersal. The aim is to present a readily understood structure to illustrate the links between spawning and stocking strategies, habitat, migration and fish production. Based on this structure, contemporary understanding of the more complex biological processes that affect density, growth and habitat are discussed in relation to some of the key requirements of managers, including stocking for rehabilitation, assessment of predation impact and development of strategies for sampling populations effectively when deriving habitat‐production models. A major conclusion is that more structured, integrated research is required to provide the basic variables needed to model links between local and global scale habitat and fish production effectively. Nevertheless, application of the current understanding of the biology of Atlantic salmon should be of great benefit to managers in extracting key information from field surveys.  相似文献   

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普氏原羚(Procapra przewalskii)是青藏高原特有物种, 为了掌握该物种的分布和种群状况, 我们于2014-2015年采用全面调查和直接计数的方法, 对普氏原羚的分布、种群和保护现状进行了调查。结果如下: 普氏原羚分布在青海湖周边12个隔离的分布点, 与全国第一次野生动物资源调查的结果相比, 有多个新的分布点被发现, 分布范围和面积扩大; 调查共发现1,238只普氏原羚, 与2010年以后的调查结果相比, 种群数量维持在一个稳定的水平。然而, 仅有4个分布点位于青海湖国家级自然保护区范围内。尽管刚察县成立了青海湖普氏原羚特护区, 天峻县成立了普氏原羚自然保护站, 但现有的管护力度仍然不够, 且缺乏系统的管理规划。我们建议在天峻县布哈河上游的生格-快尔玛地区成立普氏原羚自然保护区; 同时建立适当的生态补偿机制, 协调保护与社区发展的矛盾; 鉴于目前圈养种群发展迅速, 建议在历史分布区选取合适的地点进行人工繁育个体的迁地放归。  相似文献   

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The importance of long-distance dispersal in biodiversity conservation   总被引:4,自引:6,他引:4  
Dispersal is universally considered important for biodiversity conservation. However, the significance of long‐ as opposed to short‐distance dispersal is insufficiently recognized in the conservation context. Long‐distance dispersal (LDD) events, although typically rare, are crucial to population spread and to maintenance of genetic connectivity. The main threats to global biodiversity involve excessive LDD of elements alien to ecosystems and insufficient dispersal of native species, for example, because of habitat fragmentation. In this paper, we attempt to bridge the gap in the treatment of LDD by reviewing the conservation issues for which LDD is most important. We then demonstrate how taking LDD into consideration can improve conservation management decisions.  相似文献   

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Ong Jin-Eong 《Hydrobiologia》1995,295(1-3):343-351
Despite the recent better understanding and awareness of the role of mangroves, these coastal forest communities continue to be destroyed or degraded (or euphemistically reclaimed) at an alarming rate. The figure of 1% per year given by Ong (1982) for Malaysia can be taken as a conservative estimate of destruction of mangroves in the Asia-Pacific region. Whilst the Japanese-based mangrove wood-chips industry continues in its destructive path through the larger mangrove ecosystems of the region, the focus of mangrove destruction has shifted to the conversion of mangrove areas into aquaculture ponds and the consequences of the unprecedented massive addition of carbon dioxide to the atmosphere by post industrial man.Mangroves are non-homogeneous; characterised by distinct vegetative zones that occupy the interface between land and sea and dynamically interacting with the atmosphere above as well as with the influences of the adjacent land and sea. The conservation of mangroves should thus include not only the various vegetation and tidal inundation zones but also the adjacent marine and terrestrial areas (including the water catchment area).On the current concern with global climate change, it is pointed out that relative sea level change is very much site dependent. For effective planning and management, it is vital to know if a particular site is stable, rising or sinking so efforts should be directed to find suitable methods for determining this. However, should rapid relative sea level rise take place, there is very little likelihood of saving mangroves whose landward margins have been developed by man, a fact to bear in mind when selecting sites for conservation. The Matang mangroves of Malaysia is rare case of successful sustainable management of a tropical rain forest. Although the tools of management are available they are not widely applied. We particularly urge the Japanese mangrove wood-chips industry to look to long term sustainable use rather than short term gains. A suggestion is made to appeal to the new Government of Japan to take the lead in environmental friendliness especially to the rain forests of the Asia-Pacific region.  相似文献   

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Passerines are especially vulnerable to predation at the pre-independence stage. Although the role of nest success in British farmland passerine declines is contentious, improvement in nest success through sympathetic management could play a role in their reversal. Because habitat is known to interact with predation, management options for mitigation will need to consider effects of nest predation. We present results from an observational study of a population of Common Blackbird Turdus merula on a farm which has experienced a range of agri-environment and game-management options, including a period with nest predator control, as a case study to address some of these issues. We used an information theoretic model comparison procedure to look for evidence of interactions between habitat and nest predation, and then asked whether habitat management and nest predator abundances could explain population trends at the site through their effects on nest success. Interactions were detected between measures of predator abundance and habitat variables, and these varied with nest stage – habitat within the vicinity of the nest appeared to be important at the egg stage, and nest-placement characteristics were important at the nestling stage. Although predator control appeared to have a positive influence on Blackbird breeding population size, the non-experimental set-up meant we could not eliminate other potential explanations. Variation in breeding population size did not appear to be influenced by variation in nest success alone. Our study demonstrates that observational data can only go so far in detection of such effects, and we discuss how it might be taken further. Agri-environment and game-management techniques are likely to influence nest predation pressure on farmland passerines, but the patterns, mechanisms and importance to population processes remain not wholly understood.  相似文献   

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