A Dynamic Model for Fishery Resource with Reserve Area and Taxation

The present paper deals with a dynamic reaction model of a fishery. The dynamics of a fishery resource system in an aquatic environment consists of two zones: a free fishing zone and a reserve zone. To protect fish population from over exploitation, a control instrument tax is imposed. The existence of its steady states and their stability are studied. The optimal harvest policy is discussed next with the help of Pontryagin's maximum principle. Our theoretical results are confirmed by numerical simulation

Optimal management of a renewable resource utilized by a population with taxation as a control variable

A dynamical model is proposed and analyzed to discuss the effect of population on a resource biomass by taking into account the crowding effect. It is assumed that the resource biomass, which has commercial importance, is subjected to harvesting. The harvesting effort is assumed to be a dynamical variable and taxation is being used as a control variable. The optimal harvesting policy is discussed using the Pontryagin’s maximum principle

Modelling the Dynamics of a Renewable Resource under Harvesting with Taxation as a Control Variable

The present paper describes a model of resource biomass and population with a non-linear catch rate function on resource biomass. The harvesting effort is assumed to be a dynamical variable. Tax on per unit harvested resource biomass is used as a tool to control exploitation of the resource. Pontryagin’s Maximum Principle is used to find the optimal control to maintain the resource biomass and population at an optimal level. A numerical simulation is also carried out to support the analytical results

Designing a Decision Support System for Marine Reserves Management: An Economic Analysis for the Dutch North Sea

In this paper we discuss how a Decision Support System (DSS) for managing the marine environment can be set up. We use the Driving force-Pressure-State-Impact-Respond (DPSIR) framework to analyze which are the major driving forces impacting upon the marine environment in the North Sea. Moreover, a number of potential responses are identified. Furthermore, a preliminary and simplified optimization model has been set up and can be used in a DSS to decide on the best location of marine reserves for the protection of species. The model is based on a bio-economic metapopulation model that can be used to decide which parts of the sea should be opened for fisheries and which should be protected as marine reserve. It accounts for the dispersal of fish and considers both the economic returns from fisheries and the ecological value of marine biodiversity. A number of suggestions are given on how to extend and improve the DSS.Decision Support System, Marine Biodiversity Conservation, DPSIR Framework, Bioeconomic Modeling, North Sea

Modeling ‘No-choice’ Responses in Attribute Based Valuation Surveys

We examine the impact of providing a ‘no-choice’ option in an attribute based valuation experiment. The aim of the experiment was to assess monetary values of cockle fishery management practices in the Dutch Wadden Sea for different stakeholder groups, namely Dutch citizens, local residents, and tourists. The current policy debate about the management of the Wadden Sea stresses the fact that individual preferences with respect to cockle-fishery differ. The aim of this paper is to analyze the individual preferences in an objective way. Special attention is given to the influence of including a ‘no-choice option’, which is analyzed using a nested logit model. We test whether the full set of policy options can be considered as close substitutes. The estimation results show that the influence of including the no choice option differs among the stakeholders considered.Stakeholder valuation, Stated choice method, Multinomial logit model, Binary logit model

Protecting Marine Biodiversity: A Comparison of Individual Habitat Quotas (IHQs) and Marine Protected Areas

Fisheries managers in the United States are required to identify and mitigate the adverse impacts of fishing activity on essential fish habitat (EFH). There are additional concerns that the viability of noncommercial species, animals that are habitat dependent and/or are themselves constituents of fishery habitat may still be threatened. We consider a cap-and-trade system for habitat conservation, individual habitat quotas for fisheries, to achieve habitat conservation and species protection goals cost effectively. Individual quotas of habitat impact units (HIUs) would be distributed to fishers with an aggregate quota set to maintain a target habitat “stock” of EFH conservation. Using a dynamic, spatially explicit fishery simulation model we explore the efficiency and cost effectiveness of an IHQ policy versus alternative marine protected area (MPA) configurations, at reducing the risk of extinguishing a habitat dependent species of unknown spatial distribution. Our findings indicate that an IHQ policy with a conservatively established habitat target is better suited to the protection of non-target species than a rotating or fixed MPA policy.Fisheries management, Individual transferable quota, ITQ, Individual habitat quota, IHQ, Essential fish habitat, EFH, Marine protected areas, MPA, Non-target species

Assessment of potential mare stocking impacts on resource access rights and livelihoods in Komio village, Niger River Delta, Mali

The Community-based Fish Culture in Seasonal Floodplains and Irrigation Systems (CBFC) project is a five year research project supported by the Challenge Program on Water and Food (CPWF), with the aim of increasing productivity of seasonally occurring water bodies through aquaculture. The project has been implemented in Bangladesh, Cambodia, China, Mali and Vietnam, where technical and institutional options for community based aquaculture have been tested. The project began in 2005 and was completed in March 2010. In the context of the CP-35 project, this visit follows up on a preliminary assessment of livelihoods and institutions in Komio village, Mali conducted by consultants Joffre and Lajaunie. The objective of the visit was to determine how stocking mares around Komio village may impact livelihoods and access rights to aquatic resources. Additional insights were gained from the governance experiences and livelihood impacts of village irrigation schemes (PIVs).Fishing rights, River fisheries, Livelihoods

Coasean economics and the evolution of marine property in Hawaii

The standard view that the absence of property rights is inefficient contradicts the Coasean proposition that the relative efficiency of different institutions depends on their ability to economize on transaction costs. Moreover, the comparative theory of open access and private property institutions fails to recognize the intermediate institution of common property, finesses dynamic optimization, and provides an incomplete account of governance. We provide a comparative statics framework for alternative modes of resource management, albeit one that allows for dynamic optimization, and show that open access can be efficient under conditions of low population pressure. We show that the intensification of production with population pressure in Hawaii co- evolved with specialization and increased governance, in accordance with the efficiency theory. Instead of market-based specialization, however, economic organization in pre-contact Hawaii was hierarchically determined via top-down management of the ahupua´a.Demsetz, property rights, Hawaiian history, specialization, decentralization