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Voluntary conservation agreements are becoming increasingly important in implementing the Endangered Species Act on private land. We analyze when such agreements arise and what level of conservation they generate in the presence of uncertainty about future conservation benefits and irreversibility of habitat loss and species extinction. Our results suggest that the likelihood of an agreement and the resulting conservation levels depend on the background threat of regulation, the cost advantage offered by voluntary agreements, and the availability of assurances regarding future regulation. Under conditions likely to hold in practice, conservation agreements that offer assurances may generate higher levels of conservation and higher net social benefits than agreements that do not offer assurances. However, the resulting level of conservation will not be optimal, and may be lower than that attainable under regulation.  相似文献   

3.
Abstract: Current networks of protected areas are biased in many countries toward landscapes of low productivity. Voluntary conservation incentives have been suggested as a socially acceptable way to supplement existing networks with more productive, privately owned areas of high priority for nature conservation. The limited resources committed to nature conservation demand cost‐efficiency. Efficiency, however, depends not only on costs incurred to society from alternative ways of maintaining biodiversity but also on ecological values that can be captured. We examined the ecological efficiency of the new market‐based voluntary program to preserve forest habitats on private land in southwestern Finland. We compared sites that have become protected (10‐year contracts) in the program with managed forests, with sites that have been negotiated for protection for which no contract has been signed, and with the most ecologically valuable privately owned sites in the region that have not been offered for protection by forest owners. We surveyed sites for the amount of dead wood, wood‐decomposing fungi, and epiphytic lichens to evaluate their ecological quality. Contracted sites had more features important for overall biodiversity than managed forests and negotiated sites with no contract. These results indicate that procedures used during site selection and negotiations were appropriate and not opportunistic. The contracted sites were also as valuable in ecological terms as the best, still‐unprotected, privately owned forests in the region that have not been offered for protection. We conclude that voluntary conservation programs have the potential to yield ecologically valuable sites for protection if the site‐selection procedures are appropriate. Reliance on completely voluntary programs, however, may entail uncertainties and inadequacies, for example, in terms of spatial configuration and persistence of the ecological values. Thus, such programs may often need to be supplemented with alternative methods such as land purchase to achieve an ecologically effective network of protected sites.  相似文献   

4.
In negotiations over land‐right acquisitions, landowners have an informational advantage over conservation groups because they know more about the opportunity costs of conservation measures on their sites. This advantage creates the possibility that landowners will demand payments greater than the required minimum, where this minimum required payment is known as the landowner's willingness to accept (WTA). However, in recent studies of conservation costs, researchers have assumed landowners will accept conservation with minimum payments. We investigated the ability of landowners to demand payments above their WTA when a conservation group has identified multiple sites for protection. First, we estimated the maximum payment landowners could potentially demand, which is set when groups of landowners act as a cooperative. Next, through the simulation of conservation auctions, we explored the amount of money above landowners’ WTA (i.e., surplus) that conservation groups could cede to secure conservation agreements, again investigating the influence of landowner cooperatives. The simulations showed the informational advantage landowners held could make conservation investments up to 42% more expensive than suggested by the site WTAs. Moreover, all auctions resulted in landowners obtaining payments greater than their WTA; thus, it may be unrealistic to assume landowners will accept conservation contracts with minimum payments. Of particular significance for species conservation, conservation objectives focused on overall species richness, which therefore recognize site complementarity, create an incentive for landowners to form cooperatives to capture surplus. To the contrary, objectives in which sites are substitutes, such as the maximization of species occurrences, create a disincentive for cooperative formation. La Habilidad de Propietarios y Sus Cooperativas para Implementar Pagos Mayores que los Costos de Oportunidad en Contratos de Conservación  相似文献   

5.
Abstract:  Uncertainty in the implementation and outcomes of conservation actions that is not accounted for leaves conservation plans vulnerable to potential changes in future conditions. We used a decision-theoretic approach to investigate the effects of two types of investment uncertainty on the optimal allocation of global conservation resources for land acquisition in the Mediterranean Basin. We considered uncertainty about (1) whether investment will continue and (2) whether the acquired biodiversity assets are secure, which we termed transaction uncertainty and performance uncertainty, respectively. We also developed and tested the robustness of different rules of thumb for guiding the allocation of conservation resources when these sources of uncertainty exist. In the presence of uncertainty in future investment ability (transaction uncertainty), the optimal strategy was opportunistic, meaning the investment priority should be to act where uncertainty is highest while investment remains possible. When there was a probability that investments would fail (performance uncertainty), the optimal solution became a complex trade-off between the immediate biodiversity benefits of acting in a region and the perceived longevity of the investment. In general, regions were prioritized for investment when they had the greatest performance certainty, even if an alternative region was highly threatened or had higher biodiversity value. The improved performance of rules of thumb when accounting for uncertainty highlights the importance of explicitly incorporating sources of investment uncertainty and evaluating potential conservation investments in the context of their likely long-term success.  相似文献   

6.
Abstract:  Biodiversity conservation outcomes are closely related to the rules and institutions governing resource use. Creating local incentives for conservation through more secure resource tenure is central to conservation outcomes on private and communal lands, where the preponderance of biodiversity occurs. Conservation efforts in sub-Saharan Africa are therefore centrally concerned with governance dynamics and institutional reform processes, such as the decentralization of property rights, and how best to achieve such reforms. Traditional mechanisms for financing conservation efforts in Africa rely heavily on funds channeled through multilateral and bilateral aid agencies. The history of development aid highlights a range of constraints these aid agencies face in terms of working toward more effective resource governance arrangements and promoting reforms. Government aid agencies possess incentives for promoting large-scale and short-term projects that maximize expenditure volumes and tend to define issues in technical rather than political terms. The history of development aid suggests that these and other characteristics of aid agencies impedes their ability to influence governance reform processes and that aid funding may discourage the adoption of reforms. Greater emphasis in African conservation financing needs to be placed on flexible, small-scale investments aligned to local interests and constituencies that prioritize innovation, learning, and experimentation. Additionally, more research is required that explores the linkages between conservation funding, donor decision-making processes, and governance reforms.  相似文献   

7.
Systematic conservation planning optimizes trade‐offs between biodiversity conservation and human activities by accounting for socioeconomic costs while aiming to achieve prescribed conservation objectives. However, the most cost‐efficient conservation plan can be very dissimilar to any other plan achieving the set of conservation objectives. This is problematic under conditions of implementation uncertainty (e.g., if all or part of the plan becomes unattainable). We determined through simulations of parallel implementation of conservation plans and habitat loss the conditions under which optimal plans have limited chances of implementation and where implementation attempts would fail to meet objectives. We then devised a new, flexible method for identifying conservation priorities and scheduling conservation actions. This method entails generating a number of alternative plans, calculating the similarity in site composition among all plans, and selecting the plan with the highest density of neighboring plans in similarity space. We compared our method with the classic method that maximizes cost efficiency with synthetic and real data sets. When implementation was uncertain—a common reality—our method provided higher likelihood of achieving conservation targets. We found that χ, a measure of the shortfall in objectives achieved by a conservation plan if the plan could not be implemented entirely, was the main factor determining the relative performance of a flexibility enhanced approach to conservation prioritization. Our findings should help planning authorities prioritize conservation efforts in the face of uncertainty about future condition and availability of sites.  相似文献   

8.
Abstract:  Conservation organizations and public agencies are interested in identifying and prioritizing areas for conservation action, often acquisition or easements. Typically, this requires the use of uncertain data and vaguely defined decision criteria. I developed a decision support system to address these uncertainty issues and assist in evaluating conservation opportunities for the endangered California tiger salamander ( Ambystoma californiense ) in Santa Barbara, California. Functionally defined planning units were used to aggregate data on land suitability, land cover change, salamander presence, and movement risk along potential linkages between breeding ponds. I used a fuzzy-logic-based inference engine to evaluate the planning units and rank the relative suitability of interpond linkages for conservation action. The sensitivity of the rankings was considered with respect to uncertainty in salamander occurrence data and the relationship between land-cover-change threats and site suitability. All linkages were substantially degraded, but five areas were consistently identified with high relative suitability for conservation action despite differences in assumptions and uncertainty in biological data. The combination of functionally defined planning units and a fuzzy-logic-based decision support system provides a general framework for considering the suitability of sites for conservation action.  相似文献   

9.
The participation of private landowners in conservation is crucial to efficient biodiversity conservation. This is especially the case in settings where the share of private ownership is large and the economic costs associated with land acquisition are high. We used probit regression analysis and historical participation data to examine the likelihood of participation of Danish forest owners in a voluntary conservation program. We used the results to spatially predict the likelihood of participation of all forest owners in Denmark. We merged spatial data on the presence of forest, cadastral information on participation contracts, and individual‐level socioeconomic information about the forest owners and their households. We included predicted participation in a probability model for species survival. Uninformed and informed (included land owner characteristics) models were then incorporated into a spatial prioritization for conservation of unmanaged forests. The choice models are based on sociodemographic data on the entire population of Danish forest owners and historical data on their participation in conservation schemes. Inclusion in the model of information on private landowners’ willingness to supply land for conservation yielded at intermediate budget levels up to 30% more expected species coverage than the uninformed prioritization scheme. Our landowner‐choice model provides an example of moving toward more implementable conservation planning.  相似文献   

10.
Marxan is the most common decision-support tool used to inform the design of protected-area systems. The original version of Marxan does not consider risk and uncertainty associated with threatening processes affecting protected areas, including uncertainty about the location and condition of species’ populations and habitats now and in the future. We described and examined the functionality of a modified version of Marxan, Marxan with Probability. This software explicitly considers 4 types of uncertainty: probability that a feature exists in a particular place (estimated based on species distribution models or spatially explicit population models); probability that features in a site will be lost in the future due to a threatening process, such as climate change, natural catastrophes, and uncontrolled human interventions; probability that a feature will exist in the future due to natural successional processes, such as a fire or flood; and probability the feature exists but has been degraded by threatening processes, such as overfishing or pollution, and thus cannot contribute to conservation goals. We summarized the results of 5 studies that illustrate how each type of uncertainty can be used to inform protected area design. If there were uncertainty in species or habitat distribution, users could maximize the chance that these features were represented by including uncertainty using Marxan with Probability. Similarly, if threatening processes were considered, users minimized the chance that species or habitats were lost or degraded by using Marxan with Probability. Marxan with Probability opens up substantial new avenues for systematic conservation planning research and application by agencies.  相似文献   

11.
Climate‐change induced uncertainties in future spatial patterns of conservation‐related outcomes make it difficult to implement standard conservation‐planning paradigms. A recent study translates Markowitz's risk‐diversification strategy from finance to conservation settings, enabling conservation agents to use this diversification strategy for allocating conservation and restoration investments across space to minimize the risk associated with such uncertainty. However, this method is information intensive and requires a large number of forecasts of ecological outcomes associated with possible climate‐change scenarios for carrying out fine‐resolution conservation planning. We developed a technique for iterative, spatial portfolio analysis that can be used to allocate scarce conservation resources across a desired level of subregions in a planning landscape in the absence of a sufficient number of ecological forecasts. We applied our technique to the Prairie Pothole Region in central North America. A lack of sufficient future climate information prevented attainment of the most efficient risk‐return conservation outcomes in the Prairie Pothole Region. The difference in expected conservation returns between conservation planning with limited climate‐change information and full climate‐change information was as large as 30% for the Prairie Pothole Region even when the most efficient iterative approach was used. However, our iterative approach allowed finer resolution portfolio allocation with limited climate‐change forecasts such that the best possible risk‐return combinations were obtained. With our most efficient iterative approach, the expected loss in conservation outcomes owing to limited climate‐change information could be reduced by 17% relative to other iterative approaches.  相似文献   

12.
Evaluations of the effectiveness of protected areas often report their inadequate representation of regional variation in environmental conditions, land cover, and biological diversity. One frequent contributory explanation is the heavy reliance placed upon the designation of public as opposed to private lands for statutory protection. Given that protected area designation in Britain has no such constraint, and indeed that more than half of such areas are on private lands, we tested the a priori assumption that within this region the representation of environmental conditions and land cover within statutory protected areas would be more equitable. Despite the reduction in land ownership constraints on where protected areas can be established, a marked bias in protected area coverage remains. Protected areas in Britain tend toward regions of higher elevation, soils of lower economic potential, and coastal/estuarine habitat and fail adequately to represent areas of lower elevation and woodland habitats. Improving the current situation requires not only a more systematic approach to site selection, but a more equitable and diverse portfolio of incentives for private landowners to facilitate the decision to manage sites for conservation.  相似文献   

13.
The importance of movement corridors for maintaining connectivity within metapopulations of wild animals is a cornerstone of conservation. One common approach for determining corridor locations is least‐cost corridor (LCC) modeling, which uses algorithms within a geographic information system to search for routes with the lowest cumulative resistance between target locations on a landscape. However, the presentation of multiple LCCs that connect multiple locations generally assumes all corridors contribute equally to connectivity, regardless of the likelihood that animals will use them. Thus, LCCs may overemphasize seldom‐used longer routes and underemphasize more frequently used shorter routes. We hypothesize that, depending on conservation objectives and available biological information, weighting individual corridors on the basis of species‐specific movement, dispersal, or gene flow data may better identify effective corridors. We tested whether locations of key connectivity areas, defined as the highest 75th and 90th percentile cumulative weighted value of approximately 155,000 corridors, shift under different weighting scenarios. In addition, we quantified the amount and location of private land that intersect key connectivity areas under each weighting scheme. Some areas that appeared well connected when analyzed with unweighted corridors exhibited much less connectivity compared with weighting schemes that discount corridors with large effective distances. Furthermore, the amount and location of key connectivity areas that intersected private land varied among weighting schemes. We believe biological assumptions and conservation objectives should be explicitly incorporated to weight corridors when assessing landscape connectivity. These results are highly relevant to conservation planning because on the basis of recent interest by government agencies and nongovernmental organizations in maintaining and enhancing wildlife corridors, connectivity will likely be an important criterion for prioritization of land purchases and swaps. Efectos de los Esquemas de Ponderación sobre la Identificación de Corredores para Vida Silvestre Generados con Métodos Menos Costosos  相似文献   

14.
Abstract: Conservation development projects combine real‐estate development with conservation of land and other natural resources. Thousands of such projects have been conducted in the United States and other countries through the involvement of private developers, landowners, land trusts, and government agencies. Previous research has demonstrated the potential value of conservation development for conserving species, ecological functions, and other resource values on private lands, especially when traditional sources of conservation funding are not available. Nevertheless, the aggregate extent and effects of conservation development were previously unknown. To address this gap, we estimated the extent and trends of conservation development in the United States and characterized its key attributes to understand its aggregate contribution to land‐conservation and growth‐management objectives. We interviewed representatives from land trusts, planning agencies, and development companies, searched the Internet for conservation development projects and programs, and compiled existing databases of conservation development projects. We collected data on 3884 projects encompassing 1.38 million ha. About 43% of the projects targeted the conservation of specific plant or animal species or ecological communities of conservation concern; 84% targeted the protection of native ecosystems representative of the project area; and 42% provided buffers to existing protected areas. The percentage of protected land in conservation development projects ranged from <40% to >99%, and the effects of these projects on natural resources differed widely. We estimate that conservation development projects have protected roughly 4 million ha of land in the United States and account for about 25% of private‐land conservation activity nationwide.  相似文献   

15.
Conserving biodiversity and combating ecological hazards require cost-effective allocation of limited resources among potential management projects. Project priorities, however, can change over time as underlying social-ecological systems progress, novel priorities emerge, and management capabilities evolve. Thus, reallocation of ongoing investments in response to shifting priorities could improve management outcomes and address urgent demands, especially when additional funding is not available immediately. Resource reallocation, however, could incur transaction costs, require additional monitoring and reassessment, and be constrained by ongoing project commitments. Such complexities may prevent managers from considering potentially beneficial reallocation strategies, reducing long-term effectiveness. We propose an iterative project prioritization approach, based on marginal return-on-investment estimation and portfolio optimization, that guides resource reallocation among ongoing and new projects. Using simulation experiments in 2 case studies, we explored how this approach can improve efficacy under varying reallocation constraints, frequencies, costs, and rates of project portfolio change. Periodic budget reallocation could enhance the management of stochastically emerging invasive weeds in Australia and thus reduce the overall risk by up to 50% compared with a static budget. Reallocation frequency and the rate of new weed incursion synergistically increased the conservation gains achieved by allowing unconstrained reallocation. Conversely, budget reallocation would not improve the International Union for Conservation of Nature conservation status of threatened Australian birds due to slow rates of transition among conservation states; extinction risk could increase if portfolio reassessment is costly. Although other project prioritization studies may recommend periodic reassessment and reallocation, our findings revealed conditions when reallocation is valuable and demonstrated a structured approach that can help conservation agencies schedule and implement iterative budget-allocation decisions cost-effectively.  相似文献   

16.
It is difficult for public agencies to make optimal reserve-site selections without knowing how new public reserves might influence the configuration of private conservation. Private land trusts protect much land in the USA, but little is known about how private groups respond to conservation decisions made by other conservation agents. To fill that gap, we analyze township-level spatial data on conservation in California, Illinois, and Massachusetts to explore relationships between the location of private and public conservation land. Using linear spatial-econometric models and Bayesian spatial probit models, we find evidence that private-protected acres are clustered together in space. In California, it appears that private land conservation is attracted towards places where the government has reserves. In Illinois and Massachusetts, however, it appears that private conservation shifts away from townships with government reserves due to a mixture of spatial repulsion and simple acreage displacement.  相似文献   

17.
The availability of genomic data for an increasing number of species makes it possible to incorporate evolutionary processes into conservation plans. Recent studies show how genetic data can inform spatial conservation prioritization (SCP), but they focus on metrics of diversity and distinctness derived primarily from neutral genetic data sets. Identifying adaptive genetic markers can provide important information regarding the capacity for populations to adapt to environmental change. Yet, the effect of including metrics based on adaptive genomic data into SCP in comparison to more widely used neutral genetic metrics has not been explored. We used existing genomic data on a commercially exploited species, the giant California sea cucumber (Parastichopus californicus), to perform SCP for the coastal region of British Columbia (BC), Canada. Using a RAD-seq data set for 717 P. californicus individuals across 24 sampling locations, we identified putatively adaptive (i.e., candidate) single nucleotide polymorphisms (SNPs) based on genotype–environment associations with seafloor temperature. We calculated various metrics for both neutral and candidate SNPs and compared SCP outcomes with independent metrics and combinations of metrics. Priority areas varied depending on whether neutral or candidate SNPs were used and on the specific metric used. For example, targeting sites with a high frequency of warm-temperature-associated alleles to support persistence under future warming prioritized areas in the southern coastal region. In contrast, targeting sites with high expected heterozygosity at candidate loci to support persistence under future environmental uncertainty prioritized areas in the north. When combining metrics, all scenarios generated intermediate solutions, protecting sites that span latitudinal and thermal gradients. Our results demonstrate that distinguishing between neutral and adaptive markers can affect conservation solutions and emphasize the importance of defining objectives when choosing among various genomic metrics for SCP.  相似文献   

18.
Key goals of conservation are to protect both species and the functional and genetic diversity they represent. A strictly species-based approach may underrepresent rare, threatened, or genetically distinct species and overrepresent widespread species. Although reserves are created for a number of reasons, including economic, cultural, and ecological reasons, their efficacy has been measured primarily in terms of how well species richness is protected, and it is useful to compare how well they protect other measures of diversity. We used Proteaceae species-occurrence data in the Cape Floristic Region of South Africa to illustrate differences in the spatial distribution of species and evolutionary diversity estimated from a new maximum-likelihood molecular phylogeny. We calculated species richness, phylogenetic diversity (i.e., summed phylogenetic branch lengths in a site), and a site-aggregated measure of biogeographically weighted evolutionary distinctiveness (i.e., an abundance weighted measure that captures the unique proportion of the phylogenetic tree a species represents) for sites throughout the Cape Floristic Region. Species richness and phylogenetic diversity values were highly correlated for sites in the region, but species richness was concentrated at a few sites that underrepresented the much more spatially extensive distribution of phylogenetic diversity. Biogeographically weighted evolutionary diversity produced a scheme of prioritization distinct from the other 2 metrics and highlighted southern sites as conservation priorities. In these sites, the high values of biogeographically weighted evolutionary distinctiveness were the result of a nonrandom relation between evolutionary distinctiveness and geographical rarity, where rare species also tended to have high levels of evolutionary distinctiveness. Such distinct and rare species are of particular concern, but are not captured by conservation schemes that focus on species richness or phylogenetic diversity alone.  相似文献   

19.
Abstract: Many ecosystems exist primarily, or solely, on privately owned (freehold) or managed (leasehold) land. In rural and semirural areas, local and regional government agencies are commonly responsible for encouraging landholders to conserve native vegetation and species on these private properties. Yet these agencies often lack the capacity to design and implement conservation programs tailored to rural and semirural landholdings and instead offer one program to all landholders. Landholders may elect not to participate because the program is irrelevant to their property or personal needs; consequently, vegetation–retention objectives may not be achieved. We differentiated landholders in Queensland, Australia, according to whether they derived income from the land (production landholders) or not (nonproduction landholders). We compared these two groups to identify similarities and differences that may inform the use of policy instruments (e.g., voluntary, economic, and regulatory) in conservation program design. We interviewed 45 landholders participating in three different conservation agreement programs (price‐based rate [property tax] rebate; market‐based tender; and voluntary, permanent covenant). Production landholders were more likely to participate in short‐term programs that offered large financial incentives that applied to <25% of their property. Nonproduction landholders were more likely to participate in long‐term programs that were voluntary or offered small financial incentives that applied to >75% of their property. These results may be explained by significant differences in the personal circumstances of production and nonproduction landholders (income, education, health) and differences in their norms (beliefs about how an individual is expected to act) and attitudes. Knowledge of these differences may allow for development of conservation programs that better meet the needs of landholders and thus increase participation in conservation programs and retention of native vegetation.  相似文献   

20.
We consider contracting of a principal with an agent if multilateral externalities are present. The motivating example is that of an international climate agreement given private information about the willingness-to-pay (WTP) for emissions abatement. Due to multilateral externalities the principal uses her own emissions besides subsidies to incentivize the agent and to assure his participation. Optimal contracts equalize marginal abatement costs and, thus, can be implemented by a system of competitive permit trading. Moreover, optimal contracts can include a boundary part (i.e., the endogenous, type dependent participation constraint is binding), which is not a copy of the outside option of no contract. Compared to this outside option, a contract can increase emissions of the principal for types with a low WTP, and reduce her payoff for high types. Subsidies can be constant or even decreasing in emission reductions, and turn negative so that the agent reduces emissions and pays the principal.  相似文献   

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