Shooting at the poachers while the rhinos drown: Managing short‐ and long‐term threats to endangered wildlife in conservation reserves

This paper addresses management challenges associated with conserving endangered wildlife facing multiple threats from illegal poaching, habitat encroachment, and climate and land‐use change‐induced flooding. While poaching and encroachment challenges in conservation parks are of immediate nature, climate‐related risks exist in the long term. The park manager faces a utility function that includes as its arguments local community’s incomes, benefits to the larger society from preserving threatened species and the financial costs of monitoring and land‐use change efforts. Using the case of single‐horned rhinos in the Kaziranga National Park, India, an optimal mix of monitoring and land‐use changes is designed in presence of tradeoffs between short‐ and long‐term management efforts. As monitoring only addresses immediate challenges associated with poaching and encroachment, long‐term climatic risks remain ignored. Land‐use management offers risk‐protection as well as risk‐insurance benefits with respect to climate change‐induced flooding of the park. Recommendations for Resource Managers

• It is important to incorporate both short‐ and long‐term risks posed to endangered wildlife while investing in conservation efforts. There may exist a tradeoff between mitigating short‐ and long‐run risks due to financial and physical resource constraints. However, ignoring long‐term risks to wildlife habitats can jeopardize past conservation efforts.
• Land‐use management, both within and outside of conservation reserves, enhances resilience to climatic shocks through reducing flooding risks and must be an essential part of wildlife conservation efforts.
• Conservation efforts ignoring local community welfare considerations can become suboptimal as they lead to reduced cooperation and potential conflicts. When wildlife conservation efforts account for local community welfare implications, optimal management plans could result in lower species abundance in the short term. However, increasing the park size through additional land enrollment can mitigate some of this tradeoff.

     

Optimal harvest strategy for even‐aged stands with price uncertainty and risk of natural disturbances

We present a reservation price model to examine the joint impacts of natural disturbances and stumpage price uncertainty on the optimal harvesting decision for even‐aged forest stands. We consider a landowner who manages a loblolly pine stand to produce timber and amenities, under age‐dependent risk of wildfires and uncertainty in future timber prices. We show that the incorporation of risk of wildfires decreases the optimal reservation prices. The inclusion of risk of wildfires leads to lower land values and reduces the mean harvest age compared with the case of no‐risk of wildfires. Higher economic gains are obtained with the reservation price strategy compared with the deterministic rotation age model—a difference in the land value of $2,326 ha^?1 (21%) between the two approaches. Recommendations for Resource Managers

• Our adaptive harvest strategy shows that the incorporation of risk of wildfires decreases the optimal reservation prices compared with the case of no‐risk of wildfires.
• Low reservation prices—a price that makes the landowner indifferent between harvesting or waiting longer—result in lower economic benefits for landowners and potential conversions of lands to nonforest use.
• Forest management practices oriented to reduce the effects of catastrophic disturbances, for example, creating a more complex forest structure with different stand densities, become imperative to ensure the sustainability of forestlands in the US South.
• Our analysis also suggests that the valuation of forestry investments should consider not only the risk of catastrophic events but also uncertainty in future timber prices. Higher appraisals of land value are obtained when timber price uncertainty is explicitly recognized, providing financial incentives for landowners to invest in forestry.

     

EVALUATING THE PROSPECTS OF BENEFIT SHARING SCHEMES IN PROTECTING MOUNTAIN GORILLAS IN CENTRAL AFRICA

Presently, the mountain gorilla in Rwanda, Uganda, and the Democratic Republic of Congo is endangered mainly by poaching and habitat loss. This paper sets out to investigate the possible resolution of poaching involving the local community by using benefit sharing schemes with local communities. Using a bioeconomic model, the paper demonstrates that the current revenue sharing scheme yields suboptimal conservation outcomes. It is, however, shown that a performance‐linked benefit sharing scheme in which the Park Agency makes payment to the local community based on the growth of the gorilla stock can achieve socially optimal conservation. This scheme renders poaching effort by the local community, and therefore poaching fines and antipoaching enforcement toward the local community unnecessary. Given the huge financial outlay requirements for the ideal benefit sharing scheme, the Park Agencies in central Africa could reap more financial benefits for use in conservation if they employ an oligopolistic pricing strategy for gorilla tourism.     

ECOLOGICAL‐ECONOMIC MODELS OF SUSTAINABLE HARVEST FOR AN ENDANGERED BUT EXOTIC MEGAHERBIVORE IN NORTHERN AUSTRALIA

ABSTRACT. How can one manage wildlife under a suite of competing values? In isolation, the ecological economics of native wildlife harvest, threatened species conservation and control of exotic species are all well established sub‐disciplines of wildlife management. However, the wild banteng (Bos javanicus) population of northern Australia represents an interesting combination of these aspirations. A native bovid of Southeast Asia now ‘endangered’ in its native range, banteng were introduced into northern Australia in 1849. Today, a population of 8,000–10,000 resides on one small, isolated peninsula in western Arnhem Land, Northern Territory and is harvested by both recreational (trophy) and aboriginal subsistence hunters. Indigenous, industry and conservationist stakeholders differ in their requirements for population management. Here we analyze the ecological and economic costs/benefits of a series of potential harvest management options for Australia's banteng population, with the aim being either to: (1) maximize sustainable yield (MSY); (2) maximize harvest of trophy males; (3) maximize indigenous off‐take; (4) suppress density or completely eradicate the population; (5) minimize risk of extinction whilst limiting range expansion; (6) scenarios incorporating two or more of options 1–5. The modeling framework employed stochastic, density‐regulated matrix population models with life‐history parameters derived from (i) allometric relationships (for estimating r_max, generation length, fecundity and densities for a banteng‐sized mammal) and (ii) measured vital rates for wild and captive banteng and other Bos spp. For each management option, we present a simple economic analysis that incorporates estimated costs of management implementation and associated profits projected. Results demonstrate that revenue of >Ä$200,000 is possible from meat production and safari hunting without compromising long‐term population stability or the conservation status of this endangered bovid.     

TOWARD CONTROLLING NONPOINT SOURCE POLLUTION OF GROUNDWATER: A HIERARCHICAL POLICY FORMULATION GAME

An integrative approach to formulating agricultural policy instrument levels is suggested for controlling groundwater quality deterioration from agricultural chemical-use, while reconciling the conflicting goals of primary interest groups in the farm policy process. The paper develops a Stackelberg game-theoretic model of public policy formation that simultaneously determines endogenous price supports and nitrogen-use quota, as well as the optimal permissible water contamination. The analysis distinguishes between the private and social opportunity costs of producing agricultural crops and using groundwater as a repository for nitrate leachate from agricultural sources. It is recognized that the social benefit of using nitrogen in agriculture is less than the private benefit to producers. Private and social benefits, as well as optimal production and pollution solutions, will vary as the relative weights which policymakers attach to different social constituents change. The method developed in this paper may be applicable to any policy process in which policymakers exercise indirect influence over industrial production decisions through economic instruments.     

MODELING: A TOOL FOR ENHANCING THE SURVIVAL PROSPECTS OF AFRICAN WILDLIFE

ABSTRACT. In this article we consider the role of modeling in some aspects of the conservation of African wildlife. The first study is concerned with the endangered black rhino. Animals are being translocated from high density areas to new sites in an attempt to build up the South African population as rapidly as possible. We investigate the efficacy of different translocation strategies. Next we discuss a spatial stochastic metapopulation model used to test management strategies to enhance the survival likelihood of the rare samango monkey. The value of the model is to encourage the use of corridor policies even though there may be little apparent observable benefit in a manager's lifetime. Finally, we look at some commercial aspects of exploiting wildlife on a sustainable basis. By increasing the profitability of wildlife enterprises the incentive to conserve is increased. We look at improving the financial returns from game ranches.     

ON THE MANAGEMENT OF INTERCONNECTED WILDLIFE POPULATIONS

Abstract Economic interdependency of wildlife or fish stocks is usually attributed to ecological interdependency, such as predator–prey and competitive relationships, or to density‐dependent migration of species between different areas. This paper provides another channel for economic interdependency of wildlife where density‐independent migration and market price interaction affect the management strategies among different landowners. Management is studied under three market conditions for selling hunting licenses: price taking behavior, monopoly market, and duopoly market. Harvesting of the Scandinavian moose is used as an example. The paper provides several results on how economic interdependency works through the migration pattern. When a duopoly market is introduced, hunting license price interaction among the landowners plays an additional role in determining the optimal harvesting strategy.     

NSGA-II算法在农业水保措施配置优化中的应用

农业水保措施的配置要考虑其生态效益和经济效益.不同水保措施组合方案有其相应的生态和经济效益,如何配置使综合效益最佳是一个最优化问题.分析了农业水保措施配置最优化需要考虑的两个目标,并将其公式化,建立了水保措施配置优化模型,并应用NSGA-II多目标遗传算法求解该模型.最后,以甘肃天水市罗玉沟流域的水保措施配置为例,进行了初步应用.结果表明,采用NSGA-II算法在水保措施配置优化模型求解时,计算效率较高,优化结果稳定,具有一定的应用价值.     

CONSERVATION OF WILDLIFE. A BIO‐ECONOMIC MODEL OF A WILDLIFE RESERVE UNDER THE PRESSURE OF HABITAT DESTRUCTION AND HARVESTING OUTSIDE THE RESERVE

ABSTRACT. Biodiversity is today threatened by many factors of which destruction and reduction of habitats are considered most important for terrestrial species. One way to counteract these threats is to establish reserves with restrictions on land use and exploitation. However, very few reserves can be considered islands, wildlife species roam over large expanses, often via some density dependent dispersal process. As a consequence, habitat destruction, and exploitation, taking place outside will influence the species abundance inside the conservation area. The paper presents a theoretical model for analyzing this type of management problem. The model presented allows for both the common symmetric dispersal as well as what is called asymmetric dispersal between reserve and outside area. The main finding is that habitat destruction outside may not necessarily have negative impact upon the species abundance in the reserve. As a consequence, economic forces working in the direction of reducing the surrounding habitat have unclear effects on the species abundance within the protected area. We also find that harvesting outside the reserve may have quite modest effect on the species abundance in the reserve. This underlines the attractiveness of reserves from a conservation viewpoint.     

Real options in biodiversity conservation

The literature on optimal conversion defines rules that determine the rate at which land is irreversibly moved out of conservation into production. This paper explores the implications on these rules of allowing for a feedback between conversion decisions and the stochasticity of conservation benefits, using the well-known ecological mechanism of extinction debt as an illustration. This yields a model with a controlled-diffusion process at its core that is solved using a real-options approach and that leads to the conventional conversion rule as a special case. Calibrating the model to a specific case (Costa Rica), the paper demonstrates the presence of an augmented quasi-option value depending on the strength of the feedback. This results in quantifiable changes in land values and the amount of conservation. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Mathematical Modeling of Viral Zoonoses in Wildlife

Zoonoses are a worldwide public health concern, accounting for approximately 75% of human infectious diseases. In addition, zoonoses adversely affect agricultural production and wildlife. We review some mathematical models developed for the study of viral zoonoses in wildlife and identify areas where further modeling efforts are needed.     

The Stochastic Control Model for Use Conversion of Land

In this paper, the authors investigate the optimal conversion rate at which land use is irreversibly converted from biodiversity conservation to agricultural production. This problem is formulated as a stochastic control model, then transformed into a HJB equation involving free boundary. Since the state equation has singularity, it is difficult to directly derive the boundary value condition for the HJB equation. They provide a new method to overcome the difficulty via constructing another auxi...     

SUSTAINABLE FOREST MANAGEMENT FOR OPTIMIZING MULTISPECIES WILDLIFE HABITAT: A COASTAL DOUGLAS-FIR EXAMPLE

Wildlife species viability optimization models are developed to convert a given set of initial forest conditions, through a combination of natural growth and management treatments, to a forest system which addresses the joint habitat needs of multispecies populations over time. A linear model of forest cover and wildlife populations is used to form a system of forest management control variables for wildlife habitat modification. The paper examines two objective functions coupled to this system for optimizing sustainable joint species viability. The first maximizes the product of periodic joint viabilities over all time periods, focusing management resources on long-term equilibria, with less emphasis on conversion strategy. The second iteratively maximizes the minimum periodic joint viability over all time periods. This focuses management resources on the most limiting time periods, typically the conversion phase periods. Both objective functions resulted in either point or cyclic equilibria, with cycle lengths equal to minimum forest treatment ages. A third objective, based on maximizing the minimum individual species periodic viability is used to examine single species emphasis. Examples are developed through a case study of 92 vertebrate species found in coastal Douglas-fir stands of northwestern California.     

A dynamic model of supplier switching

While a broad branch of literature deals with the development of buyer–supplier relationships, limited research exists under which circumstances a buyer should terminate such a relationship and switch to a new supplier. Recently, Wagner and Friedl (2007) have developed a framework to analyze a static one-shot supplier switching decision when the buyer has asymmetric information about the supplier’s production costs. We extend their basic framework to a dynamic one, assuming that the supplier learns the production costs over time when he sets up the production process. Since the supplier’s cost information at the individual stages crucially determines the setup and the switching decision, it becomes essential for supply chain management to provide proper incentives so that the supplier reveals his cost information truthfully over time. We characterize the optimal setup and switching strategy as well as the optimal supply chain contract. We also compare our findings with those of the static setting to provide further insights.     

AN ALTERNATIVE SPECIFICATION FOR MODELING GROUNDWATER DYNAMICS

This research extends previous work with dynamic models to manage groundwater quality by using the consumptive nitrate use rate instead of the nitrate application rate. The analysis indicates that misspecification results in overestimation of economic benefits, and supra-optimum nitrogen fertilizer application rates and groundwater nitrate stocks at a steady state.     

Sustainable management of an alpine national park: handling the two-edged effect of tourism

Attracting visitors to an alpine national park can open up additional sources of funding for species conservation. However, tourism also brings ecologically negative impacts to the park and, in particular, to endangered species. In this paper, we discuss the handling of this two-edged effect of nature-based tourism within the context of a national park’s management decision. We develop a stylized model which frames the interaction of a representative largely unknown species, its habitat, and park visitors in an alpine ecosystem. In applying this to the protection of a rock partridge population in the Hohe Tauern National Park (Austria), we illustrate that a combined visitor and species protection policy can maximize steady state net benefits from tourism and conservation, while ensuring that the endangered species reaches its conservation target in the long run. Thus, even for a small, largely unknown species such as the rock partridge, and not only for popular species like the golden eagle, it is possible to endogenously generate a conservation budget by attracting visitors.     

农地城市流转福利优化的动态分析

以动态最优化理论为基础,通过建立理论模型研究农民福利最优和总体福利最优的农地城市流转数量和时间路径,并得出以下结论.为做到长期可持续农地城市流转,首先,必须给予农民足额的补偿,该补偿既包括农地的经济收益,也包括其非经济收益;其次,要使农民对土地的权利在流转过程中得到充分体现,增加农民和农民集体讨价还价的权利;再次,促使政府在流转决策中以农地的总体福利改进为决策目标,而不仅仅是用途转换带来的巨大经济价值;最后,在补偿的政策措施上,可灵活使用补偿基数和补偿增长速度这两个指标来进行福利补偿调控.     

Flexible contracting theory and case examples

When companies or governmental agencies arrange for contracts that call for deliveries over extended periods of time, arrangements are often made to adjust the final prices for exogenous changes in the costs of production. This paper shows, under specified conditions, how contracts can be devised which allow for price changes but at the same time still provide incentives for the producing unit to be efficient. For example, only under very specific conditions will a “pass-through” arrangement be acceptable. We show how the techniques of Geometric Programming applied to the economic theory of production can be used to analyze such problems.     

CREATION OF MARINE RESERVES AND INCENTIVES FOR BIODIVERSITY CONSERVATION

Abstract Despite a number of benefits, marine reserves provide neither incentives for fishermen to protect biodiversity nor compensation for financial loss due to the designation of the reserves. To obtain fishermen's support for marine reserves, some politicians have suggested that managers of new marine reserves should consider subsidizing or compensating those fishermen affected by the new operations. The objective of this paper is to apply principal–agent theory, which is still infrequently applied to fisheries, to define the optimal reserve area, fishing effort, and transfer payments in the context of symmetric and asymmetric information between managers and fishermen. The expected optimal reserve size under asymmetric information is smaller than that under symmetric information. Fishing efforts encouraged with a transfer payment are always less compared to those without payment. This reflects the fact that as the manager induces the fishermen to participate in the conservation program, the fishermen will take into account their effects on fish stock by decreasing their effort. Examples are also supplied to demonstrate these concepts.     

Efficiency in microfinance: financial and social performance of agricultural credit cooperatives in Bulgaria

Efficiency in microfinance requires accounting for a specific ambiguous production goal. Beyond financial performance, microfinance institutions are to be assessed with regard to their social impact. Based on a comprehensive data collection campaign on 15 Bulgarian agricultural credit cooperatives (ACCs), we compiled a database uniting financial (perennial data from 2000 to 2009) and social performance indicators (2009). The social performance assessment follows an internationally renowned methodology of social auditing. It provides the database for the construction of a social output, which, apart from outreach, evaluates social network quality, client benefits (protection from over-indebtedness) and other items that have not been assessed in efficiency analysis before. We develop a new analytical model for Data Envelopment Analysis and gain meaningful results for the sample of ACCs. Interestingly, the efficiency rankings revealed that only ACCs with sound financial performance can achieve a higher ranking in the specification including the social output.