Fishery externalities and biodiversity: Trade-offs between the viability of shrimp trawling and the conservation of Frigatebirds in French Guiana

Sustainable management of natural resources, and in particular fisheries, must take into account several conflicting objectives. This is the case in the French Guiana shrimp fishery for which profitability objectives imply a reduction in the fishing activity. On the one hand, this fishery has negative externalities on marine biodiversity due to discards. On the other hand, this fishery has positive externalities on the economy of the local community and interestingly enough on a protected seabird species in the area (the Frigatebird that feeds on discards). In this paper, we examine the viability of that system considering two sustainability objectives: an economic objective in terms of the profitability of the fishing activity, and a conservation objective in terms of the Frigatebird population. For that purpose, we have developed a dynamic model of that bioeconomic system and study here the trade-offs between the two conflicting objectives. It provides a means to quantify the necessary give and takes involving the economic and ecological objectives that would ensure a viable management solution. Our study confirms the relevance of the viability approach to address natural resource management issues, which should lead to the development of new tools for the arbitration of conflicting sustainability objectives. In particular, such tools could be used as a quantitative basis for cost–benefit analysis taking into account environmental externalities.     

Fishery externalities and biodiversity: Trade-offs between the viability of shrimp trawling and the conservation of Frigatebirds in French Guiana

Sustainable management of natural resources, and in particular fisheries, must take into account several conflicting objectives. This is the case in the French Guiana shrimp fishery for which profitability objectives imply a reduction in the fishing activity. On the one hand, this fishery has negative externalities on marine biodiversity due to discards. On the other hand, this fishery has positive externalities on the economy of the local community and interestingly enough on a protected seabird species in the area (the Frigatebird that feeds on discards). In this paper, we examine the viability of that system considering two sustainability objectives: an economic objective in terms of the profitability of the fishing activity, and a conservation objective in terms of the Frigatebird population. For that purpose, we have developed a dynamic model of that bioeconomic system and study here the trade-offs between the two conflicting objectives. It provides a means to quantify the necessary give and takes involving the economic and ecological objectives that would ensure a viable management solution. Our study confirms the relevance of the viability approach to address natural resource management issues, which should lead to the development of new tools for the arbitration of conflicting sustainability objectives. In particular, such tools could be used as a quantitative basis for cost–benefit analysis taking into account environmental externalities.     

Species diversity, fishing induced change in carrying capacity and sustainable fisheries management

It is well established in the fisheries management literature that marine ecosystems are complex and marine species depend on one another. As a result, it is important to account for species diversity to ensure sustainable management. In addition, recent research published in the marine sciences literature has provided unequivocal evidence that fishing activities destroy habitats and inhibit production of planktons. This paper illustrates that if a conventional bioeconomic model is employed, an optimum effort policy as opposed to quota appears to result in sustainable management even if fishing impacts carrying capacity. However, the so-called optimum effort may collapse the stock if species diversity is not accounted for. Conversely, if species diversity and the impact of fishing on carrying capacity are considered, neither the equilibrium quota nor effort may guarantee sustainable yield.     

Assessing the ecological and economic benefits of a no-take marine reserve

The management of marine resources is often impeded by a lack of models to integrate ecological and economic information on exploited populations. We used available biological and economic data for an overexploited population of the leopard grouper (Mycteroperca rosacea) to study if closing parts of the population to fishing would allow sustainable use and maximum economic benefits. Our results suggest that fishing should be closed in all spawning areas and in at least 50% of the adjacent areas. High non-consumptive benefits would be achieved with large closures because the abundance of the leopard groupers, which is an important attribute for SCUBA divers, would increase. In a no-take reserve, the welfare gains of divers seemingly could compensate for losses incurred by fishers if parts of their fishing grounds are closed. An adaptive management scheme could provide a way to incorporate newly available information into management decisions for the no-take reserve.     

Payments for agrobiodiversity conservation services for sustained on-farm utilization of plant and animal genetic resources

This paper discusses the potential application of Payment for Ecosystem Services-like schemes to tackle market failures associated with the public good characteristics of agrobiodiversity conservation services. So called payments for agrobiodiversity conservation services (PACS) would increase the private benefits from utilizing local plant and animal genetic resources on-farm through voluntary reward mechanisms, so as to sustain their on-farm conservation. Theoretical and applied insights about PACS are discussed and attention drawn to some of the challenges to be overcome in implementing PACS. In particular, these relate to the identification of potential buyers, the complex institutional setting in which PACS might operate and the articulation of a meaningful conservation goal based on a safe minimum standard approach. The latter is urgently needed, so as to ensure that additional agrobiodiversity services are generated. Relative to a fixed pricing approach, PACS schemes that seek to overcome information asymmetries through the use of conservation auctions may be associated with significant efficiency gains. However, potential trade-offs between ecological effectiveness, economic efficiency, and social equity considerations need to be carefully evaluated.     

The use of trade measures against illicit fishing: Economic and legal considerations

Illegal, Unreported and Unregulated (IUU) fishing activities are a threat for both the marine environment and society. By undermining effective management systems, IUU fishing activities affect economic performance, social welfare and compliance decisions. So far, “traditional” control and surveillance-like measures have had a limited success in deterring IUU fishing, so this paper aims at throwing light on several forms of trade-related initiatives that can be more effective. The paper suggests that both the effectiveness and further development of such measures strongly depend on the way they are designed, especially with respect to their trade-law compatibility. However, current discussions on future trade-based policy developments within some key economic areas suggest that trade measures are a sound option for policy makers. While the paper focuses on fisheries issues, it is also expected to inform the international debate surrounding the sustainable use of natural resources in general, as many sectors face similar biodiversity and trade challenges (e.g. tropical forest, mangroves, etc.).     

Optimum reserve size,fishing induced change in carrying capacity,and phenotypic diversity

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.     

Alternative targets and economic efficiency of selecting protected areas for biodiversity conservation in boreal forest

We examine the relative merits of alternative forest biodiversity targets, which give different weights to species according to their conservation status and abundance. A site selection framework is used for choosing the habitat-protection strategy that maximizes biodiversity subject to an upper bound on funding with six alternative conservation goals. By using Finnish data on old-growth forests, we found that alternative conservation goals yield different benefit-cost tradeoffs. Goals relying on complementarity between protected stands result in great marginal costs at a high conservation level. Therefore, under these conditions it may not be economically efficient to establish a large conservation network to protect all species in a given area. In contrast, a large conservation network is more likely to be justified when the habitat-protection strategy focuses on species abundance. The trade-offs between alternative objectives are explicitly measured by incrementally varying the weights given to the species. We found that the targets for all species representation and species abundance can largely be met simultaneously. Protecting red-listed species reduces overall species coverage and species abundance particularly at low budget levels.     

Identification of development indicators in tropical mountainous regions and some implications for natural resource policy designs: an integrated community case study

In tropical and subtropical countries a social gradient can be observed in mountainous regions between small-scale farmers on fragile ecosystems associated with human poverty, and the fertile plains and broad valleys with large-scale cash crop productions and industrial centers associated with relative economic welfare. Sustainable community development paths have to be identified in these less privileged regions. The objective of this study was to make a contribution for defining and assessing development indicators at community level, including ecological, economic and social dimensions, to elicit the conflicting objectives in development and to discuss some practical implications. The study was performed in a typical watershed in central Honduras and special attention was given to autochthonous and qualitative indicators for development. Using the pressure-state-response model as a framework, a series of indicators were identified and assessed, which were also used by the local population and grouped into landscape structure, soil fertility, water availability and quality, production system and extractive activities, economic and social performance, and institutions. The development path in this specific case illustrated the transition from an expansive forest conversion agriculture to an intensified and diversified agriculture. This was made possible through technology transfer and improved market access. However, this development path, while increasing economic welfare, generated increasing negative environmental impacts caused by pesticide residues, soil erosion and less regular water supply. As the watershed carrying capacity for traditional shifting cultivation (used as a system indicator) reached its ecological limit, new sustainable development strategies had to be identified. The implications of the study for policy design are that tools need to be provided for natural and environmental resource monitoring, which may consist of sustainability goal definitions, a minimal set of indicators and simple maps for planning land use at local level.     

云南山区生态农业产业发展思路与对策

山区农业是云南农业发展的一大难题,资源开发与生态环境问题一直是西部开发战略的核心,实现经济与环境持续发展,在生态系统承载能力范围内,充分发挥生态优势,依托地域优势,采用积极有效的经营机制,对提高农业生态系统生态能力,实现生态、经济和社会效益具有重要的意义,也是解决＂三农＂问题,建立和谐社会主义新农村必须面对的问题。面对云南山区农业令人担忧的现状,以生态农业产业为出发点,对云南山区生态农业的发展进行分析,提出了发展云南山区生态农业产业的基本思路和对策。     

Site accessibility and prioritization of nature reserves

Nature reserves not only protect habitat-stressed species but also provide recreation and welfare services to people. Therefore, site accessibility matters in reserve design. This study incorporates public accessibility, determined by urban populations and distances between urban areas and reserve sites, as an additional factor in conservation reserve design besides species representation and economic characteristics of individual sites. An optimization approach is introduced to determine a reserve network with maximum accessibility while satisfying specified representation targets under financial constraints. The paper also presents an empirical application of this approach to endangered/threatened birds in Illinois, USA, and analyzes the tradeoffs between ecological, economic, and social objectives of biological conservation. The results show that: i) the conventional minimal representation approach would result in a small reserve network, but this network would have poor accessibility; ii) public accessibility can be improved significantly by selecting alternative sites with the same amount of conservation budget; iii) further improvement in accessibility can be achieved by enlarging the network, but in this particular case the gains would be insignificant after the first few additional sites; and iv) a regionally integrated conservation plan, as opposed to decentralized conservation efforts, is beneficial for both species protection and social welfare.     

POLITICALLY FEASIBLE, REVENUE SUFFICIENT, AND ECONOMICALLY EFFICIENT MUNICIPAL WATER RATES

Water rates are designed to meet multiple objectives, typically resulting in trade-offs among the objectives of economic efficiency, revenue sufficiency, and related revenue stability. Standard theory of natural monopoly is extended here to explain why long-run marginal cost (LMC) can be greater than both average cost and short-run marginal cost (SMC) for municipal water utilities. The distinctions between "benign monopoly rates" and "marginal cost rate design" favor LMC over SMC as the basis for economically efficient rate design. Taking into account conservation investments by consumers, SMC rates are economically inefficient, except during temporary shortages. The City of Los Angeles adopted economically efficient, revenue sufficient, and revenue-stable water rates at the end of a prolonged drought. After the drought ended, Los Angeles (LA) modified the rate design, making the design politically feasible during normal rainfall years. Unique features in the LA rate design determine the allocation of consumer surplus among ratepayers, making the rate design politically feasible by sharing efficiency gains among customer classes. Revenue sufficiency and stability features in the rate design minimize adverse job effects on water utility management, reducing the frequency of rate hearings with an increasing block design. ( JEL L51, L95, Q25, Q51)     

Money,Trust, and Culture: Elements for an Institutional Approach to Money

The development gap between countries in tropical and temperate zones has been attributed to a variety of factors. Using data from the World Values Survey, we find that social norms about thrift, as opposed to sharing, vary with the length of the winter season. We also show that this cultural dimension “thrift versus sharing” and institutional quality both have an independent effect on contemporary economic outcomes. This suggests that the tropical development gap might be the consequence of deep-rooted effects of pre-industrial agro-climatic conditions on both the quality of institutions and social norms about thrift versus sharing that fostered development in the industrial era.     

Ecological and economic sustainability in fishery management: A multi-agent model for understanding competition and cooperation

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.     

The Impact of Land-Use Change on Ecosystem Services,Biodiversity and Returns to Landowners: A Case Study in the State of Minnesota

Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands, wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits (private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately reflect social returns.     

Economic valuation of the Leuser National Park on Sumatra,Indonesia

The Leuser Ecosystem in Northern Sumatra is officially protected by its status as an Indonesian national park. Nevertheless, it remains under severe threat of deforestation. Rainforest destruction has already caused a decline in ecological functions and services. Besides, it is affecting numerous economic activities in and around the Leuser National Park. The objectives of this study are twofold: firstly, to determine the total economic value (TEV) of the Leuser Ecosystem through a systems dynamic model. And secondly, to evaluate the economic consequences of deforestation versus conservation, disaggregating the economic value for the main stakeholders and regions involved. Using a dynamic simulation model, economic valuation is applied to evaluate the TEV of the Leuser National Park over the period 2000–2030. Three scenarios are considered: ‘conservation’, ‘deforestation’ and, ‘selective use’. The results are presented in terms of (1) the type of benefits, (2) the allocation of these benefits among stakeholders, and (3) the regional distribution of benefits. The economic benefits considered include: water supply, fisheries, flood and drought prevention, agriculture and plantations, hydro-electricity, tourism, biodiversity, carbon sequestration, fire prevention, non-timber forest products, and timber. The stakeholders include: local community members, the local government, the logging and plantation industry, the national government, and the international community. The regions considered cover the 11 districts involved in the management of the Leuser Ecosystem. With a 4% discount rate, the accumulated TEV for the ecosystem over the 30-year period is: US $7.0 billion under the ‘deforestation scenario’, US $9.5 billion under the ‘conservation scenario’ and US $9.1 billion under the ‘selective utilisation scenario’. The main contributors in the conservation and selective use scenarios are water supply, flood prevention, tourism and agriculture. Timber revenues play an important role in the deforestation scenario. Compared to deforestation, conservation of the Leuser Ecosystem benefits all categories of stakeholders, except for the elite logging and plantation industry.     

A Bioeconomic Analysis of Marine Reserves for Paua (Abalone) Management at Stewart Island,New Zealand

Traditional fisheries management relies on the imposition of gear and/or effort restrictions. In spite of much experience with such techniques, the danger of fishery collapse is ever present. Biologists have advocated an alternative strategy, the establishment of marine reserves. However, it is possible that the benefits of marine reserve creation can be overstated if economic behaviour is ignored. In spite of being managed under a system of transferable quotas, the Stewart Island paua (abalone) fishery has been in decline for some time. We develop an integrated economic and biological model of this fishery and use it to predict biomass levels in a number of scenarios, including the imposition of a network of no-take areas. We identify circumstances under which the marine reserve solution outperforms traditional management techniques. We show that the benefit of a marine reserve is highest when a fishery is heavily exploited and when accounting for stochastic recruitment.     

Challenges for economic policy in sustainable management of marine natural resources

The sustainable management of marine natural resources presents particular challenges to the managers of those resources. While such management has typically been based on biological considerations, it is argued that this has resulted in overexploitation and destruction of important marine assets in industries such as fishing and tourism. Consequently, it is concluded that other approaches are needed, with the use of economic concepts and management tools particularly relevant. At the same time, the human welfare outcomes of the application of various policy instruments must be carefully considered. While biological information is critical to the formulation and implementation of successful management regimes, it is concluded that the application of economic instruments will become more attractive to resource managers, with these instruments underpinned by consideration of property rights and an appropriate allocation of economic rents. A greater focus on these economic matters will take resource managers further in the direction of sustainable management of increasingly scarce marine resources. The conclusions in the paper are supported by various case studies from fisheries and tourism.     

Impacts of birdwatching tourism on environment and economy

Birdwatching tourism can be a good model for nature conservation and economic development if it is managed with the well-being of local ecosystems and human communities. Birdwatchers can bring financial sources to local nature conservation. Many communities and local leaders consider birdwatching as a significant mean to develop local economics and publicize regional image, but only few research have tried to study the impacts of relevant activities on destinations. The purpose of the paper is to give a comprehensive review on impacts of birdwatching from conservation economics and biology perspective. Use a behavioral approach study impacts of birdwatching tourism on environment and economy. Specific objectives here are： （1） review the value and significance on environment and economy; （2） economic potential of non-residential birdwatching for community-based conservations; （3） using a behavioral approach, combine quantitative and qualitative methods study birdwatching impacts; （4） outline the economic and environmental benefits and problems associated with the activity; and （5） aid community leaders and tourism business related company in their efforts to improving the value of birdwatching; help the leaders of natural reserve areas develop birdwatching tourism.     

The role of natural capital in supporting national income and social welfare

Using life satisfaction as a proxy for social welfare, this study contributes to the extant literature by empirically demonstrating that natural capital contributes to social welfare, functioning in part through increasing national income and in part through its direct effect on life satisfaction; the direct effect is approximately 40% greater than the indirect effect. This suggests that the true welfare benefits of natural capital may not be adequately reflected in conventional economic data and, therefore, studies seeking to evaluate the contribution of natural capital to human well-being should consider employing data sets that capture subjective elements of welfare. The magnitudes of the reported marginal effects of natural capital on social welfare, however, are small. This is perhaps due to the fact that (1) there are shortcomings in the measure of natural capital; (2) life satisfaction effects are unlikely to reflect the poorly understood benefits that natural capital provides; and (3) keystone species (such as mosquitoes) and integral ecosystems (such as wetlands) may be negatively associated with life satisfaction, even though such components of natural capital are vitally important to sustaining ecosystems and human life