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1.
This study combines niche modeling and systematic area prioritization using distribution data for 131 species of amphibians and reptiles from Northeast India and Burma, with two objectives: (i) to evaluate the performance of the current conservation area network in Northeast India with respect to the representation of amphibians and reptiles, and (ii) to identify potential areas for expanding the current conservation area network. In a two-step protocol, maximum entropy niche modeling was used to project species’ potential geographic occurrences, and the resulting probabilistic distribution data were used to prioritize areas with algorithms that maximize the representation of all species in minimal total area. The results provided a critical assessment of conservation priorities in this data-deficient region, and indicate the utility of combining niche modeling with systematic area prioritization in such situations. Many areas that had been overlooked in previous assessments were identified. Although the existing protected areas were found to be inadequate for representation of amphibian and reptile diversity, the prioritization results show that by targeting a minimal representation of 5% of the current total area suitable for each species, the gaps can be filled with a relatively modest (0.41%) increase in the current total area covered by the network. Extended analyses were also performed to assess the effects of putatively rare species on reserve selection, which showed that the inclusion of these taxa can change the prioritization solutions significantly. The prioritization results also highlight areas of Northeast India that warrant attention from future surveys.  相似文献   

2.
National and International Red Lists and Legal Acts specify species with conservation needs, mainly on the basis of personal experiences. For effective conservation we need scientifically justified prioritization and grouping of these species. We propose a new combined approach where species are grouped according to the similar activities needed for their conservation. We used the national list of vascular plant species with conservation need for Estonia (301 species), and linked these species to eight qualitative conservation characteristics, four reflecting natural causes of rarity (restricted global distribution; restricted local distribution within a country; always small populations; very rare habitat type), and four connected with nature management (species needing the management of semi-natural grasslands; species needing local disturbances like forest fires; species needing traditional extensive agriculture; species which may be threatened by collecting). Only one positive association occurred among the characteristics - between restricted local distribution and small size of populations. Thus, natural causes of rarity and management aspects are not overlapping, and both should be used in conservation activities. Species grouping by different conservation characteristics allows one to focus on species groups with similar conservation needs instead of individual species. Prioritization of species with conservation needs can be based on the number of conservation characteristics that are associated with a particular species. Our prioritization did not correlate with the categories of the national Red Data Book, but a positive association was found with legal protection categories. The legislation, however, covers only the natural causes of rarity. We propose a new combined approach for plant species’ conservation planning that starts by considering human induced rarity and progresses through to natural rarity causes.  相似文献   

3.
Agricultural landscapes are the dominating landscape types in many parts of the world. Land-use intensification and spatial homogeneity are major threats to biodiversity in these landscapes. Thus cost-effective strategies for species conservation in large-scale agricultural landscapes are required. Spatial optimisation methods can be applied to identify the most effective allocation of a given budget for conservation. However, the optimisation of spatial land-use patterns in real landscapes on a large spatial scale is often limited by computational power. In this paper, we present a simplifying methodology for analysing cost-effectiveness of management actions on a regional scale. A spatially explicit optimisation approach is employed to identify optimum agricultural land-use patterns with respect to an ecological-economic goal function. Based on the optimisation results for small scale landscape samples we derive a target- and site-specific cost-benefit function that can be applied to predict ecological improvement as a function of costs and local conditions on a large spatial scale. Thus, it is possible to identify areas where management actions for ecological improvement are most efficient with respect to a certain conservation goal. The fitted function is validated independently. In a case study, we analyse cost-effectiveness of management actions to enhance habitat suitability for three different target species. The approach is flexible and could be applied to a variety of other landscape planning problems dealing with the effective allocation of management measures.  相似文献   

4.
Freshwater ecosystems are among the most threatened in the world. In light of the threats to freshwater biodiversity, it is essential to map the distribution and status of species to ascertain their threat status for prioritizing conservation action. However, while there is agreement that the conservation of freshwater ecosystems depends on whole-catchment management, there are still a wide variety of large-scale mapping methods in use, the advantages and disadvantages of which have not been fully explored. This study shows that area estimation based on minimum convex polygons should not be encouraged for aquatic species. The IUCN definition of area of occupancy (AOO) is a useful term, albeit highly scale-dependent, for assessment of the total approximate area over which a species occurs. However, for aquatic fauna, and perhaps many other organisms, assessment of occurrence should be based on the more accurate point-locality presences only. The IUCN extent of occurrence (EOO), for freshwater catchment species, should be redefined as ‘the sum of the smallest hydrological units identified, of presently known, inferred or projected occurrences of a taxon, excluding cases of vagrancy, that are used to estimate the threat to a taxon’. A single hydrological unit is also the conservation or management unit. Here we suggest that this unit is the quaternary catchment. This new mapping approach is more appropriate and practical for use in both management planning and conservation action. We suggest that conservation managers and decision makers facilitate co-operation in freshwater mapping efforts by working at the same spatial scale, i.e. the same hydrological unit.  相似文献   

5.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

6.
The present study is the first to determine priorities for the location of marine reserves using spatial prioritization software in the eastern Mediterranean Sea. We used biophysical data from visual census surveys on: fish species abundance, presence of various habitat types, and percent coverage of seagrasses and canopy algae. Efficient conservation planning requires spatially explicit information on how proposed management will affect stakeholders, which in this region was very limited. We created novel socio-economic cost indices to account for fisheries and tourists. Our fishing metrics were based on fisher behaviour including information on the location of ports and areas often inaccessible to fishers due to high wind exposure. We developed a cost index for tourism based on the availability of beds for tourists. We examined how the spatial priorities for marine reserves varied using different combinations of these socio-economic cost metrics. We found about 17% of sites were a high priority regardless of which cost metric was used. We also compared, for the first time in the Mediterranean, our results devised using systematic conservation planning approaches with priorities developed by two non-systematic methods, the Natura 2000 proposed marine reserves and sites that local fishers proposed for protection. Only a few sites identified by our approach were the same as those recommended as part of Natura 2000 or the fishers’ proposals. This suggests that much more work is needed to harmonise existing proposals with the principles of efficient systematic conservation planning.  相似文献   

7.
Conservation involves making decisions on appropriate action from a wide range of options. For conservation to be effective, decision-makers need to know what actions do and do not work. Ideally, decisions should be based on effectiveness as demonstrated by scientific experiment or systematic review of evidence. Can decision-makers get this kind of information? We undertook a formal assessment of the extent to which scientific evidence is being used in conservation practice by conducting a survey of management plans and their compilers from major conservation organizations within the UK. Data collected suggest that the majority of conservation actions remain experience-based and rely heavily on traditional land management practices because, many management interventions remain unevaluated and, although some evidence exists, much is not readily accessible in a suitable form. We argue that nature conservation along with other fields of applied ecology, should exploit the concept of evidence-based practice developed and used in medicine and public health that aims to provide the best available evidence to the decision-maker(s) on the likely outcomes of alternative actions. Through critical evaluation, we present the challenges and benefits of adopting evidence based practice from the decision-makers point of view and identify the process to be followed to make it work.  相似文献   

8.
The integration of freshwater and terrestrial biodiversity priorities in systematic conservation planning is a major challenge to conservation planners. Maintaining upstream–downstream connectivity and the influence of catchments on freshwater ecological integrity are some of the issues that make it difficult to reconcile terrestrial and freshwater conservation planning. As a result most conservation assessments are often biased towards terrestrial systems without adequate incorporation of freshwater biodiversity in determining priority areas for conservation. In this paper, we propose a protocol for integrating the assessment of freshwater and terrestrial priorities in conservation planning, based on a case study from Mpumalanga Province in South Africa. The approach involves the separate assessment of freshwater priority areas, and using the outcome to influence the selection of terrestrial priority areas. This allowed both freshwater and terrestrial biodiversity to be incorporated in conservation planning without compromising their unique requirements. To test the effectiveness of this approach, we assessed percentage overlap between freshwater and terrestrial priority areas, target achievement, and the area required to achieve targets. We then compared the outcome from the proposed approach with the separate assessments of freshwater and terrestrial biodiversity priorities, and when both systems are given an equal weighting in a single assessment. The results showed that there was a noticeable improvement in the overlap of priority areas for freshwater and terrestrial biodiversity from 23% to 47%. Target achievement for freshwater biodiversity improved by 10% when terrestrial assessment was based on freshwater priority areas as opposed to terrestrial systems being assessed alone. There was negligible increase in area required, whether there was integration of freshwater and terrestrial biodiversity or no integration. We conclude that the most efficient way to achieve integration in conservation planning is to preferentially select areas where freshwater and terrestrial biodiversity priorities overlap.  相似文献   

9.
Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6 × 6 km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82–100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining ‘proportion of area occupied’, we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as ‘probability of habitat used’. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands.  相似文献   

10.
Objective approaches are needed to select species for monitoring management effectiveness and to justify conservation investments. We develop and apply two approaches for selecting the most cost-effective and informative indicator species with a case study of monitoring investments in invasive predator control in south-western Australia. We compared species selected by a qualitative approach involving experts scoring 17 criteria for 12 potential indicators to a quantitative metric based on empirical data for a subset of criteria. Both approaches accounted for the monitoring cost, potential for leverage, data uncertainty and the risk of choosing an un-representative or un-informative indicator, albeit in different ways. The indicator species selected by the quantitative metric was the western brushtail possum Trichosurus vulpecula – a relatively common medium-sized mammal in the study region. When costs were not considered explicitly in the qualitative approach, the indicator selected was the woylie Bettongia penicillata. When costs were sensibly incorporated in the qualitative approach, indicator rankings changed and the top-ranked species was again T. vulpecula. Although when costs were included the qualitative expert-driven approach delivered the same result as the quantitative metric, it was not robust to minor data adjustments, and incorporating expert uncertainty made it difficult to distinguish the value of potential indicator species from each other. The quantitative metric was comparatively robust to minor data adjustments, and enabled evaluation of data uncertainty in a transparent way, presenting a more objective approach that enables explicit selection of the most informative indicator for monitoring management actions.  相似文献   

11.
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12.
Target-based spatial prioritization is the default approach in conservation resource allocation. Here, we clarify a poorly known feature of target-based spatial prioritization that may lead to an unbalanced allocation of resources between species or other biodiversity features. Highest per-species resources will be allocated to species occurring in costly and otherwise species-poor locations, whereas smallest per-species resources will be allocated to species that occur in species-rich locations at low-cost areas. Uncertainty in information about processes determining distributions of biodiversity features may lead to uncertainty in target setting. This can be a problem if unnecessarily high targets emerge to consume excessive resources thus detracting from other conservation action. Difficulties might be encountered in particular when there are many features, targets are given simultaneously to multiple different types of biodiversity features, or components of features, or when there are interactions or correlations between features. Consequently, we recommend that the costs of targets for individual features could be evaluated to screen for such targets that consume a disproportionate fraction of available resources. Costs of targets can be evaluated by a variant of the replacement cost technique. We also find that commonly used reserve selection methods, minimum set coverage, maximum coverage, and utility maximization differ significantly in how they treat targets and their costs.  相似文献   

13.
The main role of conservation planning is to design reserve networks to protect biodiversity in situ. Research within the field of conservation planning has focused on the development of theories and tools to design reserve networks that protect biodiversity in an efficient and representative manner. Whilst much progress has been made in this regard, there has been limited assessment of the sensitivity of conservation planning outcomes to uncertainty associated with the datasets used for conservation planning. Predicted species distribution data are commonly used for conservation planning because the alternatives (e.g. survey data) are incomplete or biased spatially. However, there may be considerable uncertainty associated with the use of predicted species distribution data, particularly given the variety of approaches available to generate a dataset from such predictions for use in conservation planning. These approaches range from using the probabilistic data directly to using a threshold identified a priori or a posteriori to convert the probabilistic data to presence/absence data. We assess the sensitivity of conservation planning outcomes to different uses of predicted species distribution data. The resulting reserve networks differed, and had different expected species representation. The choice of approach will depend on how much risk a conservation planner is willing to tolerate and how much efficiency can be sacrificed.  相似文献   

14.
Romania’s protected areas network currently covers 19.29% of the national territory, a significant increase from the 4.1% protected prior to 1989. The increase occurred over the past 20 years with the creation of 27 National and Natural Parks, and recently of 382 protected areas as part of the pan-European Natura 2000 network. Considering the recent increase in number and area of protected lands, we investigated two core topics critical to achieving conservation goals: (1) conservation value and (2) resources for conservation. The newly created Natura 2000 sites overlapped 96.19% of the existing protected areas network, generating up to three different protection statuses for some sites. Conservation goals were often unclear, as the focus switched to protecting species and habitats of European-level concern. Despite the fivefold increase in protected area, many ecoregions were poorly represented in the new system. Planning for conservation neither involved the local communities nor utilized principles for spatial prioritization. Over 80% of the species of European conservation concern were included in at least one protected area, but plants and invertebrates were underrepresented. Administrative bodies were generally under-staffed and poorly financed, conditions that were reflected in a poor enforcement and implementation of conservation goals. Overall, Romania shares many conservation concerns with other Eastern and Central European countries. A regional approach to conserving biodiversity based on spatial prioritization, rigorous scientific documentation, and social acceptance is needed for the Natura 2000 network to achieve its goals.  相似文献   

15.
Systematic conservation planning has become an important tool for increasing the efficiency of conservation decisions, but many planning efforts result in static plans that may lose relevance over time. We developed a process whereby planning is integrated into the decision-making process and updated every six months in response to conservation actions. The Florida Forever program is a 10-year, $3 billion land acquisition program expected to acquire approximately 1.25 million acres (607,000 ha) for conservation in Florida through the year 2010. With limited funding and duration, the program needs to be able to efficiently protect the most natural resources for a fixed cost, a situation well suited to a systematic reserve design approach. To inform this program, we conducted an assessment of natural resource conservation needs and developed the Florida Forever Tool for Efficient Resource Acquisition and Conservation (F-TRAC), a systematic reserve design analysis based on a simulated annealing site selection algorithm using Marxan software. The analysis considered conservation needs for a variety of natural resources including species, natural communities, high quality watersheds, wetlands, and sustainable forestry. Each 6-month analysis identifies an efficient portfolio of sites for resource protection, given the amount of land area likely remaining to be acquired by the Florida Forever program. The Spring 2004 model portfolio had a cost threshold of 206,308 ha, met conservation targets for 18 of 32 resource conservation features, and identified approximately 116,000 ha outside of current land acquisition projects. This study also demonstrates the use of reserve design results to evaluate existing and proposed land acquisition projects and inform decision makers; and the evaluation of acquisition trends and program success based on potential achievements as indicated by reserve design analyses.  相似文献   

16.
A number of global priority region schemes have been developed, but local assessments are needed to identify priority areas for conservation within these regions. Here, we describe results from a conservation assessment for Maputaland, part of a biodiversity hotspot in southern Africa that is also the focus of the Lubombo Transfrontier Conservation Area (TFCA) initiative between South Africa, Mozambique and Swaziland. The TFCA seeks to establish new state-, private- and communally-managed conservation areas to boost economic development through nature-based tourism and game ranching. The assessment will guide the TFCA process and used a systematic conservation planning approach to design a landscape to conserve 44 landcover types, 53 species and 14 ecological processes. The assessment also included data on modelled risk of agricultural transformation, of which low-risk areas were selected where possible. The current PA systems in the three countries cover 3830 km2, which represents 21.2% of the region, and meet the representation targets for 46% of the conservation features. The proposed conservation landscape adds 4291 km2 of new core areas and 480 km2 of linkages and, if appropriate, could provide potential revenues of US$18.8 million from game ranching, based on modelled large ungulate density, life history and game auction data. We also discuss the benefits of including data on widely distributed, better known conservation features together with less-well studied, range-restricted species and the advantages of using agricultural transformation risk data in conservation assessments.  相似文献   

17.
An approach to an overall management planning for the conservation of endangered species within protected natural areas is presented, based mainly on the development of methods for the diagnosis of the conservation status and the identification of critical life cycle stages (phenophases) of target species. This model includes other aspects inherent in the overall planning of a protected area so as to match its technical, human and economic resources in terms of research and conservation. We provide examples of some island endemics that are included in the “Recovery Plans for the Endangered Plants in the Canary Islands National Parks”. The use of demography and genetics is particularly emphasised. We propose reintroductions as one of the most important tools for the management and conservation of endangered plants and the use of “system dynamics” tools as an alternative to traditional population matrix analysis. We provide examples of the application of system dynamics to population dynamics studies and to the design of management actions.  相似文献   

18.
Conservation prioritization is an important consideration for planning of natural resources management, allowing decison makers to implement management strategies that are more sustainable in the long-term. However, only a current erosion status or a relative index cannot exactly identify priority area for conservation. The objective of this paper is to identify conservation priorities by a specific multicriteria evaluation method. Trends in erosion risk indicate regions of increasing erosion risk and are also chosen as one of the evaluation criteria to identify the priorities based on the instability of soil erosion in the Yongding river basin. In this paper, vegetation cover, land-use, and slope gradient are used to assess erosion risk and trends in erosion risk are obtained by comparing the results of erosion risk between 2000 and 2006. Using this information, the priority conservation areas are graded into six levels. The two highest priority levels cover the regions with severe erosion or a substantial recent increase in erosion risk (4722.56 km2, or 11.82% of the study area), and are recommended as erosion control regions with appropriate conservation strategies. The middle two levels cover the regions with stable erosion status or slight change, needing only minor measures. The method presented is fast and straightforward, showing good potential for successful application in other areas.  相似文献   

19.
We developed an interactive management model for wild and captive populations of the ploughshare tortoise or angonoka, Geochelone yniphora. Interactive management is based on the translocation of individuals between wild and captive populations to simulate a metapopulation. Demographic parameters of one captive and two wild populations of this rare tortoise were used to conduct a metapopulation viability analysis (MVA). The effectiveness of the conservation strategy proposed for this species was then evaluated by modifying the probability of extinction and growth of the metapopulation over a fixed period of time. Several alternative scenarios of interactive management were then tested and ranked in terms of their effect on the viability of the metapopulation. The model predicted that catastrophic events such as bush fires would likely have a negative effect on the future of remaining wild populations. However, the model also predicted that the use of captive-born offspring to establish additional wild populations would decrease the risk of extinction of the metapopulation as a whole. We believe that, when supported by sound knowledge of the demographic parameters of a species, the use of MVA as part of an interactive management program can be an effective conservation tool that allows assessment of the probable response of both captive and wild populations to different management alternatives. One of the most interesting aspects of this interactive management approach is the link between in situ and ex situ conservation.  相似文献   

20.
The increasing popularity of outdoor recreational activities in recent years has resulted in elevated human disturbance of waterbird communities. Anthropogenic disturbance is defined as any human activity that constitutes a stimulus sufficient to disrupt normal activities and/or distribution of animals relative to the situation in the absence of that activity. The goals of this study were (1) to quantify changes in habitat use by waterbirds caused by the proximity of people’s activities to the shoreline, in Los Padres Lagoon Reserve (Argentina), (2) to evaluate differential responses of waterbird groups caused by this human disturbance, and (3) to propose management guidelines to improve waterbird conservation in Pampas lagoon. We performed bird surveys monthly in areas with high levels of disturbance (HD areas) and with no or low levels of disturbance (LD areas) via recreational activities during days with (weekends) and without (weekdays) presence of people close to the lagoon. We recorded 34 bird species using the lagoon. The bird richness and abundance in HD areas was higher in days without recreational activities, conversely, in LD areas we found no differences in these parameters between days. Waders were found to be the group most vulnerable to disturbance, since these birds were only recorded in HD areas in days without human activity. Podicipedidae, as a group were less affected by recreational activities. We detected changes in the waterbird assembles and structure in relation to the presence of people on the shoreline. Our results in this study suggest direct effects of recreational activities on the habitat use of waterbirds. The buffer area defined by the current Reserve management strategy is working properly, and the impact of recreational activities on transitional area has only instantaneous effects on waterbirds because they return to that area in absence of disturbance. However, it should be considered that we only estimated the response to short-term effects of these activities on the waterbird community. Further studies should assess long-term effects.  相似文献   

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