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1.
A model of individual behavior for recreational fisheries which considers both the participation decision and the activity level decision is developed. The model also distinguishes between the catch rate, which is a biologically determined parameter, and the landings rate, which is a control variable. Individual and fisherywide equilibria under open access are described for both homogeneous and heterogeneous participants. Optimal utilization is also described. Optimal utilization differs from open access in terms of activity levels of participants and number and type of participants. Regulations to achieve optimal utilization are described.  相似文献   

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Abstract: Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive‐management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles.  相似文献   

4.
As coastal populations expand, demands for recreational opportunities on beaches and coastal dunes grow correspondingly. Although dunes are known to be sensitive to direct human disturbance and provide irreplaceable ecosystem services (e.g. erosion control, critical habitat and nesting sites), dunes serve as campsites for large numbers of people (∼90,000 p.a.) on the ocean-exposed shores of Fraser Island, Australia. Campsites are located in the established dunes and can only be accessed with 4WD vehicles along tracks cut directly from the beach through the foredunes. Here we quantified the extent of physical damage to foredunes caused by this practice, and tested whether human-induced physical changes to foredunes translate into biological effects. Of the 124 km of ocean-exposed beaches, 122 km (98%) are open to vehicles driven on the beaches, and camping zones cover 28.7 km or 23% of the dunes. A total of 235 vehicle tracks are cut across the foredunes at an average density of eight tracks per km of beach. These tracks have effectively destroyed one-fifth (20.2%) of the dune front in camping zones, deeply incising the dune-beach interface. There is evidence of accelerated erosion and shoreline retreat centred around vehicle tracks, resulting in a “scalloping” of the shoreline. No dune vegetation remains in the tracks and the abundance of ghost crabs (Ocypode spp.) is significantly reduced compared with the abutting dunes. Because current levels of environmental change caused by dune camping may not be compatible with the sustainable use of coastal resources and conservation obligations for the island (listed as a World Heritage Area and gazetted as a National Park), restoration and mitigation interventions are critical. These will require spatial prioritisation of effort, and we present a multi-criteria ranking method, based on quantitative measures of environmental damage and ecological attributes, to objectively target rehabilitation and conservation measures. Ultimately, coastal management needs to develop and implement strategies that reconcile demands for human recreation, including beach camping, with conservation of coastal dune ecosystems.  相似文献   

5.
The purpose of this paper is to comment on and extend the analysis of a paper by Wetzel. He uses a commonly accepted model of demand for a congested recreational resource and shows how the Clawson method of estimating a recreational demand curve relates to it. Much of his analysis is useful but he errs in his interpretation of the proper value of consumer surplus. In this paper a specific formalization of the demand model is developed for the first time and it is used to show the correct measure of consumer surplus and how to specify the proper level of use for the congested resource.  相似文献   

6.
In order to take account of the congestion externalities associated with increased use intensity during a given period at a low density recreational resource, it is necessary to determine the effects of alternative use levels on the expected quality of each individual's experience. This paper describes a simulation model for wilderness recreation designed to provide such measures. In order to illustrate the model it is applied to the Spanish Peaks Areas in Montana.  相似文献   

7.
The purpose of this paper is to develop and estimate a simultaneous model of recreation participation. The logic of the model is that participation in one activity (for example, boating) is influenced by and influences participation in other activities (for example, fishing). For the empirical part of our paper we have used the simultaneous logit model developed by P. Schmidt and R. P. Strauss (Econometrics43, 745–755, 1975). For the application, we have applied the simultaneous logit model to participation in summer recreational activities in Rhode Island. Our results show that simultaneous equation models tend to forecast better, but that the specification bias from excluding the endogenous variables tends to be small.  相似文献   

8.
Recreational fisheries are increasingly important in fisheries management; for some species, recreational take rivals or exceeds the amount harvested by commercial fishermen. Most recreational fisheries are regulated with gear restrictions, bag limits, and time/area closures, but there is increasing interest in the market-based solutions employed in commercial fisheries — this despite the lack of an adequate bioeconomic theory of the joint commercial/recreational aspects of many recreational fisheries. This paper integrates a detailed production specification with traditional bioeconomic tools in order to better understand the implications of rationalization schemes targeted at the charter sector. While confirming some of the qualitative conclusions of the commercial fisheries literature on open access and regulated open access our model also generates rich and novel predictions with respect to input choices, the number of vessels and congestion externalities. We devise a system of instruments that generate efficient outcomes and extensively discuss issues associated with their real-world implementation.  相似文献   

9.
In coastal wetlands, the increasing level of disturbance from recreational activities could threaten waterbird populations, which overall are showing decreasing trends. Despite the crucial contribution of waterbirds to biodiversity, empirical studies measuring the effects of disturbance on them remain scarce, especially in terms of the impact upon their roosting sites. We developed an experimental treatment to measure the effects of a pedestrian walking on a site used by overwintering waterbirds in a wetland of international importance. We registered 156 events (88 at high tide) of flushing birds, totaling 4,018 individuals. Each treatment drove the flushing of 1?C5?% of the wintering populations of nearly all species present during high tide. In addition, 1.5?% of the Eurasian curlew wintering population was driven to change site. All the effects were found to be reduced during other tidal periods. Therefore, allowing recreational use in a previously undisturbed area can systematically increase daily energy expenditure of significant percentages of different waterbird populations during high tide, and even cause birds to avoid a site completely. These effects will probably be even worse given that our results were derived only from a disturbance source of low magnitude and frequency. We recommend that, prior to developing recreational areas close to the shoreline, coastal wetland managers should study the habitat use of waterbirds during high tide in relation to total waterbird populations using the wetland.  相似文献   

10.
Green electricity products are increasingly made available to consumers in many countries in order to address a number of environmental and social concerns. Most of the literature on this green electricity market focuses on consumers’ characteristics and product attributes that could affect participation. However, the contribution of this environmental consumerism to the overall environmental good does not depend on participation alone. The real impact relies on market participation for green consumers (the proportion of green consumers) combined with the level of green consumption intensity – the commitment levels, or proportion of consumption that is green. We design an online interface that closely mimics the real market decision environment for electricity consumers in Western Australia and use an error component model to analyze consumers’ choice of green electricity products and their commitment levels. We show that product attributes have limited impact on the choice of green products; however, there is still great potential for better participation by improving the design of green electricity programs. When green products are selected, most respondents select the minimum commitment possible, and this is insensitive to the premium being charged on green power, suggesting that we are largely observing a buy-in ‘warm glow’ for carbon mitigation.  相似文献   

11.
The frequently discussed gap between conservation science and practice is manifest in the gap between spatial conservation prioritization plans and their implementation. We analyzed the research‐implementation gap of one zoning case by comparing results of a spatial prioritization analysis aimed at avoiding ecological impact of peat mining in a regional zoning process with the final zoning plan. We examined the relatively complex planning process to determine the gaps among research, zoning, and decision making. We quantified the ecological costs of the differing trade‐offs between ecological and socioeconomic factors included in the different zoning suggestions by comparing the landscape‐level loss of ecological features (species occurrences, habitat area, etc.) between the different solutions for spatial allocation of peat mining. We also discussed with the scientists and planners the reasons for differing zoning suggestions. The implemented plan differed from the scientists suggestion in that its focus was individual ecological features rather than all the ecological features for which there were data; planners and decision makers considered effects of peat mining on areas not included in the prioritization analysis; zoning was not truly seen as a resource‐allocation process and not emphasized in general minimizing ecological losses while satisfying economic needs (peat‐mining potential); and decision makers based their prioritization of sites on site‐level information showing high ecological value and on single legislative factors instead of finding a cost‐effective landscape‐level solution. We believe that if the zoning and decision‐making processes are very complex, then the usefulness of science‐based prioritization tools is likely to be reduced. Nevertheless, we found that high‐end tools were useful in clearly exposing trade‐offs between conservation and resource utilization.  相似文献   

12.
Providing insight on decisions to hunt and trade bushmeat can facilitate improved management interventions that typically include enforcement, alternative employment, and donation of livestock. Conservation interventions to regulate bushmeat hunting and trade have hitherto been based on assumptions of utility- (i.e., personal benefits) maximizing behavior, which influences the types of incentives designed. However, if individuals instead strive to minimize regret, interventions may be misguided. We tested support for 3 hypotheses regarding decision rules through a choice experiment in Tanzania. We estimated models based on the assumptions of random utility maximization (RUM) and pure random regret maximization (P-RRM) and combinations thereof. One of these models had an attribute-specific decision rule and another had a class-specific decision rule. The RUM model outperformed the P-RRM model, but the attribute-specific model performed better. Allowing respondents with different decision rules and preference heterogeneity within each decision rule in a class-specific model performed best, revealing that 55% of the sample used a P-RRM decision rule. Individuals using a P-RRM decision rule responded less to enforcement, salary, and livestock donation than did individuals using the RUM decision rule. Hence, 3 common strategies, enforcement, alternative income-generating activities, and providing livestock as a substitute protein, are likely less effective in changing the behavior of more than half of respondents. Only salary elicited a large (i.e. elastic) response, and only for one RUM class. Policies to regulate the bushmeat trade based solely on the assumption of individuals maximizing utility, may fail for a significant proportion of the sample. Despite the superior performance of models that allow both RUM and P-RRM decision rules there are drawbacks that must be considered before use in the Global South, where very little is known about the social–psychology of decision making.  相似文献   

13.
Social animals are extraordinarily diverse and ecologically abundant. In understanding the success of complex animal societies, task differentiation has been identified as a central mechanism underlying the emergence and performance of adaptive collective behaviors. In this study, we explore how individual differences in behavior and body size determine task allocation in the social spider Stegodyphus dumicola. We found that individuals with high body condition indices were less likely to participate in prey capture, and individuals’ tendency to engage in prey capture was not associated with either their behavioral traits or body size. No traits were associated with individuals’ propensity to participation in web repair, but small individuals were more likely to engage in standard web-building. We also discovered consistent, differences among colonies in their collective behavior (i.e., colony-level personality). At the colony level, within-colony variation in behavior (aggressiveness) and body size were positively associated with aggressive foraging behavior. Together, our findings reveal a subtly complex relationship between individual variation and collective behavior in this species. We close by comparing the relationship between individual variation and social organization in nine species of social spider. We conclude that intraspecific variation is a major force behind the social organization of multiple independently derived lineages of social spider.  相似文献   

14.
Conservation scientists are increasingly focusing on the drivers of human behavior and on the implications of various sources of uncertainty for management decision making. Trophy hunting has been suggested as a conservation tool because it gives economic value to wildlife, but recent examples show that overharvesting is a substantial problem and that data limitations are rife. We use a case study of trophy hunting of an endangered antelope, the mountain nyala (Tragelaphus buxtoni), to explore how uncertainties generated by population monitoring and poaching interact with decision making by 2 key stakeholders: the safari companies and the government. We built a management strategy evaluation model that encompasses the population dynamics of mountain nyala, a monitoring model, and a company decision making model. We investigated scenarios of investment into antipoaching and monitoring by governments and safari companies. Harvest strategy was robust to the uncertainty in the population estimates obtained from monitoring, but poaching had a much stronger effect on quota and sustainability. Hence, reducing poaching is in the interests of companies wishing to increase the profitability of their enterprises, for example by engaging community members as game scouts. There is a threshold level of uncertainty in the population estimates beyond which the year‐to‐year variation in the trophy quota prevented planning by the safari companies. This suggests a role for government in ensuring that a baseline level of population monitoring is carried out such that this level is not exceeded. Our results illustrate the importance of considering the incentives of multiple stakeholders when designing frameworks for resource use and when designing management frameworks to address the particular sources of uncertainty that affect system sustainability most heavily. Incentivando el Monitoreo y el Cumplimiento en la Caza de Trofeos  相似文献   

15.
Sandy beaches represent typical venues for recreation and tourism worldwide, as well as part of the lifestyle and identity of coastal communities. Their overexploitation, however, threatens their survival. Especially in urban areas, beach management requires balancing needs by different users and obligations to protect beach functions, including conservation. In light of this, research about the human dimension of beach ecosystems has been advanced as a way to assist planning and decision making in beach management. This study assessed beachgoers' perceptions of sandy beach conditions in South Africa, by means of a questionnaire survey. The effects of demographic profile, travelling habits, motivations to visit, and recreational preferences on beachgoers' perceptions of beach conditions were tested. Beachgoers shared a general concern for the wellbeing of sandy beaches, with particular reference to the state of biodiversity and conservation. They also gave great importance to the values underlying beach ecosystems. Three motivations to visit groups and four recreational preferences types were identified. Demography, travelling habits, motivations to visit, and recreational preferences all influenced perceptions of beach conditions. The results from this study were used to draw management recommendations, with particular attention towards the promotion of conservation while also maintaining the recreational quality of urban sandy beaches. The results also highlighted the relevance of considering users' views as a tool in decision-making processes in Integrated Coastal Zone Management.  相似文献   

16.
The suitable spectral mode in remote sensing is often desirable to facilitate the inversion of ecological environment and landscape. This paper put forward an optimizing model based on variable precision rough sets (VPRS) for the land cover discrimination in wetland inventory. In the case study of Lake Baiyangdian which has important ecological functions to the northern China, this model is established successfully according to the domain-experts knowledge. The procedure is as follows. First step is data collection, including remote-sensing data (e.g., Landsat-5 TM bands), the digitized relief maps, and statistical yearbooks. Second, the remote sensing imagery (RSI) and relief maps are co-registered into the same resolution. Third, a condition set, including various attributes is derived from spectral bands, band math or ratio indices based on previous studies, at the same time, the decision set is derived from true land types after investigation and validation. Then, the remote sensing decision table (RSDT) is constructed by linking condition set with decision set according to the sequential pixels in RSI. Fourth, we create one forward greedy searching algorithm based on VPRS to handle this RSDT. After adjusting parameters such as β and knowledge granularity diameter (KGD), we obtain the stable optimized results. Comparative experiments and evaluation show that the discrimination or retrieval accuracy of VPRS model is satisfying (overall accuracy: 87.32% and KHAT: 0.84) and better than original data. Moreover, data dimension has been decreased dramatically (from 12 to 3) and key attributes found by the model may be useful for specific retrieval in wetland inventories.  相似文献   

17.
Protected areas (PAs) are a frequently used conservation strategy, yet their socioeconomic impacts on local communities remain contentious. A shift toward increased participation by local communities in PA governance seeks to deliver benefits for human well‐being and biodiversity. Although participation is considered critical to the success of PAs, few researchers have investigated individuals’ decisions to participate and what this means for how local people experience the costs and benefits of conservation. We explored who participates in PA governance associations and why; the perceived benefits and costs to participation; and how costs and benefits are distributed within and between communities. Methods included 3 focus groups, 37 interviews, and 217 questionnaire surveys conducted in 3 communities and other stakeholders (e.g., employees of a nongovernmental organization and government officials) in PA governance in Madagascar. Our study design was grounded in the theory of planned behavior (TPB), the most commonly applied behavior model in social psychology. Participation in PA governance was limited by miscommunication and lack of knowledge about who could get involved and how. Respondents perceived limited benefits and high costs and uneven distribution of these within and between communities. Men, poorer households, and people in remote villages reported the highest costs. Our findings illustrate challenges related to comanagement of PAs: understanding the heterogeneous nature of communities; ensuring all households are represented in governance participation; understanding differences in the meaning of forest protection; and targeting interventions to reach households most in need to avoid elite capture.  相似文献   

18.
Local residents’ active participation is essential in protected areas to ensure achievement of conservation goals. One of the important steps for ensuring the active participation of local residents is to determine the perceptions and the factors that influence the perceptions of the local residents toward the protected area. In this context, the researchers of this study try to come up with the perception formed among the local residents toward the protected areas and especially toward Kure Mountains National Park (KMNP), the factors that would influence their perceptions and the ways how their perceptions are influenced. Multivariate linear regression was used to examine the putative influence of variables on perceptions toward protected areas. According to study results, the survey respondents have displayed a positive perception toward the protected areas in the world and in KMNP. It was determined that the respondents formed a positive perception from their economic, environmental and recreational interaction with KMNP. Also, the outcomes of this study showed that the perception developed by local residents toward the protected areas in the world and KMNP are influenced by gender, the level of satisfaction derived from the national park, duration of their residence in the national park, and that the perception that KMNP conservation are beneficial for the source values of the area, the current protection works in the world, as well as its impacts on their living conditions.  相似文献   

19.
Changes in human behavior are a precursor to measurable impacts of no-take marine reserves. We investigated changes in recreational fishing site selection in response to the 2005 announcement of enforcement in a marine reserve in the Gulf of California, Mexico. We used a novel data set of daily self-reported boating destinations from emergency rescue logbooks for a recreational angling community from 2000 to 2008. Because the reserve system has no experimental control, we modeled the data two ways to test for robustness to model specification. We tested for changes in human fishing behavior with regression and fit a fleet-level discrete choice model to project a. counterfactual scenario. The counterfactual is the statistically constructed ex post expectation of the human behavior we would have observed if the reserve never existed. We included month and year fixed effects in our models to account for seasonal and interannual fluctuations in fishing behavior and catch rates. We detected a decrease in reserve use compared to the counterfactual, indicating that the reserve rapidly experienced a decrease in visitation. However, the reserve's effect to reduce trips diminished with time. These results indicate that the reserve is unlikely to meet its ecological goals without institutional changes that enhance compliance. This illustrates the value of human use data to understanding the processes underlying marine reserve function. We suggest that managers should consider human use with the same frequency, rigor, and tools as they do fishery stocks. Marine reserves directly affect people, and understanding human behavioral responses to marine reserves is an important step in marine reserve management.  相似文献   

20.
A number of classic papers conclude that if a congestible facility is the property of a profit maximizing entrepreneur, he will impose a charge for use that induces the socially optimal level of use and congestion. All these papers happen to deal with a special case in which that conclusion holds, but it is not true in general. In general, the socially optimal level of use of a congestible facility is the level at which the marginal cost of providing the service is equal to the sum of the decreases in the users' willingnesses to pay for a unit of service when the level of congestion is optimal, and need not coincide with the level resulting from a profit-maximizing charge. This sum is derived from the integral under a fictitious demand curve constructed by imagining that the level of congestion is the same (and optimal) at all levels of the use-charge.  相似文献   

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