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1.
The recreational value of coral reefs: A meta-analysis   总被引:3,自引:0,他引:3  
Coral reefs are highly productive ecosystems that provide a variety of valuable goods and services, including recreational opportunities. The open-access nature and public good characteristics of coral reefs often result in them being undervalued in decision making related to their use and conservation. In response to this, there now exists a substantial economic valuation literature on coral reefs. For the purposes of conducting a meta-analysis of this literature, we collected 166 coral reef valuation studies, 52 of which provided sufficient information for a statistical meta-analysis, yielding 100 separate value observations in total. Focusing on recreational values, we use US$ per visit as the dependent variable in our meta-analysis. The meta-regression results reveal a number of important factors in explaining variation in coral reef recreational values, notably the area of dive sites and the number of visitors. Different valuation methods are shown to produce widely different values, with the contingent valuation method producing significantly lower value estimates. Using a multi-level modelling approach we also control for authorship effects, which proves to be highly significant in explaining variation in value estimates. We assess the prospects for using this analysis for out-of-sample value transfer, and find average transfer errors of 186%. We conclude that there is a need for further high-quality valuation research on coral reefs.  相似文献   

2.
The Tonle Sap wetland fishery was previously divided into 3 different management zones for conservation, open access fishing and private fishing. Rights to the private fishing zone involved auctions for exclusive rights to temporarily designated plots. This paper aims to explore the auction-based system by investigating how this fishery management system affects different groups of small scale fishermen and how different characteristics of the fishing lots affect the bidding. A choice experiment approach was used to model fishermen's choices in a hypothetical auction market by offering fishermen the choice between purchasing different potential fishing lots and a no purchase option, implying fishing only in the communal fishing grounds. The preferred latent class model with two segments of fishermen showed that the bidding behavior of the more privileged group out-competes the other group irrespective of the lot characteristics. This result suggests that it is unlikely that the redesign of the auction system itself would be an effective way of securing access to fishing resources for the two observed groups of fishermen. This implies that open access fishing grounds and/or other regulations may also be needed in future management as they serve an important role for the poorer segments.  相似文献   

3.
Recent studies have shown that many marine ecosystems are experiencing an accelerating loss of population and biodiversity. It is apparent that there is a growing disparity between the available supply of fish and the desire of the growing world population to catch them. Although studies have begun to question the ecological sustainability of managed fishery systems, they often omit the corresponding effects on the economic sustainability of fishery industries. This is particularly important in rural coastal areas where the fishing industry is often a dominant employer. In this article, we analyze the interactions between economic and ecological dynamic systems using a multi-agent dynamic model of fishery management. Multiple agents (fishers) harvest multiple fish species and adapt the amount and allocation of their effort to their value functions, which are given as net profits of the fish harvest sold for a market price. This is largely unique in fishery models, since many econometric studies view fishers as represented by homogenous ‘average’ agents. We introduce and compare two different decision rules governing the behavior of fishers engaged in a competitive market. We demonstrate a situation where both behaviors lead to a decline of all fish stocks, as well as profits for most fishers. As an alternative, we introduce a cooperative approach in which fisheries jointly set sustainable limits for total harvest and effort that are then distributed to the fishers according to distribution rules. The simulation reveals that fish stocks and profits can stabilize at significantly higher levels in the cooperative case, leading to a continuous accumulation of capital for all fishers. This model demonstrates key aspects of overfishing conflicts that can be overcome through planned fishing quotas and cooperative market mechanisms. It also demonstrates a novel approach for simulating the dynamic behavior of heterogeneous fishers.  相似文献   

4.
We estimated the economic value of changes in the quality of a coral reef ecosystem to SCUBA divers in the Caribbean using a stated preference mail survey. Our sampling frame was all divers with U.S. home addresses who purchased a tag required for diving in the Bonaire National Marine Park in 2001. Divers were asked how they might have altered their trip choice had the quality of the coral reef system been different from what they experienced. From these responses we inferred the value of three different levels of quality defined by visibility, species diversity, and percent coral cover. We used random utility theory and mixed logit to analyze the choice questions. Our sample size was 211, and our survey response rate was 75%. For modest changes in quality we estimated per person annual losses at $45. For larger losses the value was $192. Presented at the 3rd World Congress of Environmental and Resource Economists in Kyoto, Japan, July 2006.  相似文献   

5.
Recreational fishermen derive utility from catch and fishing effort. Building our analysis on the Gordon-Clark model for renewable resources, we show that a lower importance of catch may result in higher catches. While this effect also holds under first-best management, it may destabilize open-access recreational fisheries to the point of stock collapse. Technical progress in recreational fisheries may mask such dynamics as it enables unaltered angler behavior and constant catches during stock declines.  相似文献   

6.
Water temperature is an important factor affecting aquatic life within the stream environment. Cold water species, such as salmonids, are particularly susceptible to elevated water temperatures. This paper examines the economic value of short‐term water temperature forecasts for salmonid management. Forecasts may have economic value if they allow the water resource manager to make better water allocation decisions. This study considers two applications: water releases for management of Chinook salmon in the Klamath River and leasing water from agriculture for management of steelhead trout in the John Day River. We incorporate biophysical models and water temperature distribution data into a Bayesian framework to simulate changes in fish populations and the corresponding benefit from recreational fishing and opportunity cost of water under different temperature forecast accuracies. Simulation results indicate that use of the forecasts results in increased fish production and that marginal costs decline and net benefits increase as forecast accuracy increases, suggesting that provision and use of such stream temperature forecasts would have value to society. (JEL Q22, Q25, Q28, Q50)  相似文献   

7.
Using a bioeconomic model of a coral reef-mangrove-seagrass system, we analyze the dynamic path of incentives to achieve an efficient transition to the steady state levels of fish biomass and mangrove habitat conservation. Our model nests different types of species habitat dependency and allows for changes in the extent of habitat to affect the growth rate and the long-run fish level. We solve the two-control, two-state non-linear optimal control problem numerically and compute the input efficiency frontier characterizing the tradeoff between mangrove habitat and fish population. After identifying the optimal locus on the frontier, we determine the optimal transition path to the frontier from a set of initial conditions to illustrate the necessary investments. Finally, we demonstrate how dynamic conservation incentives (payments for ecosystem services) for a particular habitat with multiple services are interdependent, change over time, and can be greater than contemporaneous fishing profits when the ecosystem is degraded.  相似文献   

8.
Exploitation of the marine ecosystem brings with it an intertemporal choice: there is a choice of catching the fish today, or restrain from fishing with the option of an increase in the benefit from future harvest. In a marine ecosystem under common pool management regime the contribution margin from catching the fish belongs to the fisher, while the benefit from the investment of leaving the fish in the sea will be shared in the common pool. The intertemporal choice therefore creates a driver for short sighted use of the ecosystem. The intertemporal balance of the exploitation is analyzed by applying capital theory to a size-based ecosystem model. The model reveals a need for intertemporal balance with respect to both fish size and harvest volume. The management therefore is, at an ecosystem level, to set target and regulate not only harvest volume but also size.  相似文献   

9.
Economists have relied on convexity assumptions for a long time but many natural resources that stem from ecosystems have non-convexities in their dynamics. This article illustrates the consequences of relaxing convexity assumptions for management and the role of fast and slow variables. The paper presents a general framework to handle systems with fast and slow variables, and illustrates the method using a model of coral reefs subject to fishing pressure. The insights obtained are used to discuss alternative management strategies.

Electronic Supplementary Material Supplementary material is available in the online version of this article at .   相似文献   

10.
Fish stocks around the world are heavily overexploited in spite of fishing policies in several parts of the world designed to limit overfishing. Recent studies have found that the complexity of ecological systems and the diversity of species, as well as negative impact of fishing activities on environmental carrying capacity of fish stocks—all contribute to the problem. A number of biologists, managers, and practitioners strongly support the use of marine reserves as a management strategy for marine conservation. This paper contributes to this line of research by seeking an optimum reserve size and fishing effort for situations where species diversity decrease at fishing grounds and fishing activities impact carrying capacity. We found that a reserve size which maximizes economic rents could ruin a fish stock if fishing impacts are not accounted for. On the other hand, the reserve serves as a bifurcation term which could improve the resilience of a marine ecosystem.  相似文献   

11.
In Switzerland 60% of electricity is produced by hydropower plants. The construction and operation of these plants determine some negative environmental externalities, such as diminishing groundwater levels and spring flows, and a reduction in river flow, which can severely curtail recreational and fishing activities. This study concentrates on an ex-ante appraisal of the monetary benefits resulting from an enhancement of river flow for recreational fishing purposes. A comparison of estimates of these benefits to the corresponding costs, in terms of loss of electricity production, incurred by hydropower plants to alleviate low flows may be useful for policy makers. For this analysis, as suggested by Layman et al. (Land Economics 72, pp. 113-128, 1996), the Travel Cost Method (TCM) is extended to estimate the economic value of recreational fishing in the Ticino River (the most important river of the Canton Ticino) under existing and hypothetical river flow conditions. Anglers were asked to state how the number of trips they took to the Ticino River would change if an increase in the river flow was imposed on the hydropower plants. The empirical results show that an enhancement of river flow increases the annual consumer surplus for a typical angler by approximately 440 SFr.  相似文献   

12.
In this paper we apply the repeated nested multinomial logit model, a version of a random utility model (RUM), to estimate the choice of an overnight versus single day recreation trip, along with the other usual choice of which of the sites to visit, and less typically, the choice of whether to participate (in our application – to fish) at all. We also find statistically significant income effects in the empirical results. The application is to Atlantic Salmon fishing and the data set is for Maine resident angler's fishing trips to rivers in Maine and Canada.  相似文献   

13.
Recreation demand models frequently are used to explain outdoor recreation behavior and to estimate willingness to pay for changes in environmental quality at recreation sites. Among the most commonly used recreation demand models are site choice models based on the multinomial logit framework, which account for the spatial relationships between each recreator's home and multiple alternative destinations thereby capturing the substitution possibilities among recreation sites. However, standard applications of this framework typically do not account for the possibility of spatial connections among the sites via movements of the target species, such as fish in connected water bodies in recreational angling applications or terrestrial species in hunting or wildlife viewing applications. In this paper we examine aspects of environmental valuation and natural resource dynamics that generally are addressed separately. Specifically, we show that in such spatially connected systems, a “reduced form” application of the standard site choice modeling approach, using proxy measures of environmental quality rather than direct measures of species abundances, can produce biased estimates of willingness to pay for environmental improvements. Furthermore, we show that under some conditions poorly targeted environmental improvements in spatially connected systems can lead to welfare decreases. In such systems a structural model of recreator site choices and species sorting behavior and population dynamics may be required to fully account for the spatial linkages among sites and the feedback effects between recreators and the target species.  相似文献   

14.
Estimation of consistent parameter estimates for recreational demand models faces challenges arising from the choice-based nature of the data collected primarily for resource management purposes. As an alternative to randomized respondent-based sampling, choice-based onsite sampling can provide information on actual choices made by a subset of the population where participation has a low incidence. While the literature has shown that under specific restrictions the estimation of choice models from onsite sampling data yields unbiased fixed parameter estimates for the conditional logit model, this result does not carry over to estimation of the random parameter logit model. We propose an estimator for the unbiased estimation of the random parameter model using choice-based data; our estimator uses weights based on information about the level of sampling effort. An empirical application of the standard and weighted discrete choice RUM models to onsite sample data on recreational fishing illustrates the advantages of the proposed estimator. The estimation results indicate the compensating variation associated with an decrease, or increase, of 50 % in expected catch rates for a recreational shoreline sportfishing trip to a man-made structure in southern California is $$-{\$}2.80$$ or $${\$}3.54$$ per trip, respectively.  相似文献   

15.
An age structured model of a fishery is studied where two fishing fleets, or fishing agents, are targeting two different mature age classes of the fish stock. The agents are using different fishing gear with different fishing selectivity. The model includes young and old mature fish that can be harvested, in addition to an age class of immature fish. The paper describes the optimal harvesting policy under different assumptions on the objectives of the social planner and on fishing selectivity. First, biomass yield is maximized under perfect fishing selectivity, second, equilibrium profit (rent) is maximized under perfect fishing selectivity, and third, equilibrium profit is maximized under imperfect fishing selectivity. The paper provides results that differ significantly from the standard lumped parameter (also surplus production, or biomass) model.  相似文献   

16.
The optimal fishing pattern in a multi-cohort fishery is determined using risk theory.Portfolio theory becomes applicable by treating different age groups of fish as different assets. A possibility set is derived using data on Icelandic cod fisheries. In the presence of risk aversion, it is shown that the abrupt behavior found in deterministic models is changed towards a smoother fishing pattern. The historical selection pattern for the Icelandic cod stock is shown to be near optimal using a maximal effort-type cost function, but historical levels of effort are inefficient and lead to less profit and greater fluctuations than implied by profit or utility maximization.  相似文献   

17.
This dissertation focuses on the political economy of fisheries governance. The study develops a formal model of fisheries governance by combining the features of the common pool fishery and the political institution of lobbying; designs a laboratory fishery governance institution and conducts economic experiments to test the hypotheses derived from the formal model. Specifically, the study analyzes how fishing firms invest in efforts to influence fishery regulation and management through voluntary contribution lobbying. The study also analyses and compares contribution and effort behavior in the lobbying and the CPR using data from economic experiments. The results indicate that lobbying to change suboptimal fishery regulations was significantly below the subgame perfect equilibrium prediction and contributions to raise the cap were significantly different than contributions to lower the cap toward the social optimum. Study results show that subjects successfully lobbied to raise inefficiently low fishing quotas, but were unable to lobby to reduce inefficiently high fishing quotas. Detailed analysis of subjects’ contribution and effort behavior suggest that despite the interesting benefit-cost duality between pure public goods and CPRs, the pattern of cooperative behavior in these two social dilemma situations was different and the level of cooperation in the voluntary contribution lobbying experiment was lower than those reported in other public goods experiments. To provide external validity to these experimental findings, the study further analyzes and compares lobbying expenditures in the fishery sector with those in other natural resource industries using field data from the United States. A comparison of actual lobbying expenditures as percentage of valued added shows that lobbying effort in the U.S fishery sector is not significantly different than those in other natural resource industries such as mining and electric utility industries, but the pattern of lobbying is different. Whereas fishing firms lobby through associations or pressure groups, firms in other natural resource industries lobby unilaterally. This observation suggests that differences in industrial structure and incentives influence the pattern of lobbying and the lobbying behavior of firms across industries. The theoretical predictions derived from the formal model of fisheries governance are consistent with our experimental findings and with the field data on lobbying in the US fisheries sector. These findings suggest that heterogeneity drives rent-seeking activities in the US fisheries sector and that fishing firms attempt to circumvent political collective action problems by forming and lobbying through associations of stakeholders with relatively homogenous policy preferences. JEL Classification D22, D72, D78, H41 Advisor: Prof. Jon G. Sutinen  相似文献   

18.
A key element in evaluating fishery management strategies is examining their effects on the economic performance of fishery participants, yet nearly all empirical studies of fisheries focus exclusively on the amount of fish harvested. The economic benefits derived from fish stocks involve the amount of revenue generated from fish processing, which is linked to both the way fish are harvested and the products produced from the fish. In this study we econometrically estimate a flexible revenue function for catcher-processor vessels operating in the Alaskan pollock fishery, recognizing potential endogeneity and a variety of fishing inputs and conditions. We find significant own-price supply responses and product substitutability, and enhanced revenues from increased fishing days and tow duration after a regulatory change introduced property rights through a new fishing cooperative. We also find significant growth in economic productivity, or higher revenues over time after controlling for observed productive factors and price changes, which exceeds that attributable to increased harvest. These patterns suggest that the move to rights-based management has contributed significantly to economic performance in the pollock fishery.  相似文献   

19.
Coevolution of economic and ecological systems   总被引:1,自引:1,他引:0  
This paper analyzes a model of economy–environment coevolution in which economic activities induce the genetic evolution of a biological species. This model is applied to the problem of pesticide resistance management. Just as in Munro (Environ Resour Econ, 9:429–449, 1997), we consider three main types of interactions: (1) a large pest population reduces economic revenues, (2) economic activities select for resistant genes and (3) the spread of resistant genes affects the size of the pest population. The model differs from Munro in that it includes evolutionary modeling of economic strategies. Economic agents are assumed to be boundedly rational, i.e they cannot compute the optimal level of pesticide use that minimizes resistance among pests. Economic evolution represents the change in the distribution of pesticide strategies in the population of economic agents and is modeled by a replicator dynamics equation. The interactions between economic evolution of pesticide strategies, pest population dynamics and genetic evolution of resistance of pests are studied in a system of three differential equations. We explore the dynamics and stability properties of the system using numerical simulations.  相似文献   

20.
The history of the management of Baltic fishery resources suggests that both biological and non-biological factors influence management decisions and that both types of information are essential for management which promotes sustainability. There is a direct link between the exploitation level and the risks for fishing as an economic activity due to fluctuations in the resource. This paper analyses the sustainability of the present catch levels of major Baltic fish stocks. By examining the rate of fishing mortality and recruitment variability, the possibility of sustaining present catch levels can be investigated. Current catch levels of Baltic cod and some salmon stocks are not sustainable whereas sprat and herring catches are. High rates of fishing mortality of cod and salmon may endanger stocks if a drop in the recruitment causes an increase of the fishing mortality rates in order to sustain short-term catches. By analysing the trade off between exploitation level and risk of stock decline, managers can obtain a basis for quota negotiations.  相似文献   

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