Fishing Revenue, Productivity and Product Choice in the Alaskan Pollock Fishery

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.     

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.     

Reconciling economic and biological modeling of migratory fish stocks: Optimal management of the Atlantic salmon fishery in the Baltic Sea

The paper puts forward a model of the Atlantic salmon fishery in the Baltic Sea that integrates the salient biological and economic characteristics of migratory fish stocks. Designed to be compatible with the framework used for actual stock assessments, the model accounts for age-structured population dynamics, the seasonal harvest and competing harvesting by commercial and recreational fishermen. It is parameterized for the Simojoki River stock. The socially optimal policy for maximizing discounted net benefits from the fishery within an uncertain environment is determined using a dynamic programming approach and numerical solution method. Our results indicate that substantial economic benefits could be realized under optimal management without compromising stock sustainability.     

Boundary conditions for the sustainable use of major fish stocks in the Baltic Sea

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.     

A model for estimating fish population and optimal fishing effort in lakes and rivers

We developed a model for estimating the fish population for various species in lakes and rivers. Our estimation focuses, in its first step, on fish species that breed outside the lake. Using the annual outside supply of fingerlings, natural survival rate and reported amounts of fish caught, we estimated fish stock. Given the estimated stock for fish bred outside the lake, we can evaluate the catch rate. Assuming equal catch rates for other species, and given the amount caught for each species, we are able to evaluate each species stock. Using the proposed technique, we evaluated various species stocks in the Sea of Galilee (Lake Kinneret) in Israel. Using our suggested technique for evaluating fish stock, we calculated the optimal effort of fishing needed for maximizing steady state profit of the fishers.     

Costs and Benefits of Bycatch Reduction Devices in European Brown Shrimp Trawl Fisheries

Discarding of juvenile fish is a wellrecognised problem in shrimp fisheries. In manycases, these fish are commercial species that,if not caught, could increase the productivityof other fisheries. In January 2003, Europeanlegislation was implemented by Member Statesrequiring all vessels fishing for brown shrimpto use selective trawls in order to minimisethe bycatch of other commercial species. Incomplying with the regulations, however, thecatch rate of the target species (the shrimp)is likely to be reduced. In this paper, we usea bioeconomic model to assess the impact ofbycatch reduction devices on fishing effort,catch and profitability in the European Crangon fisheries. The potential benefits (interms of higher future yields and consequentlyhigher profits) to the white-fish fisheries arealso estimated. From the model results, theregulation is expected to result in a netreduction in the profitability of the shrimpfishers. However, the benefits to thewhite-fish fishers is expected to more thanoffset this cost, resulting in an overall netbenefit.     

Cooperative and Non-Cooperative Exploitation of the Arcto-Norwegian Cod Stock

A two-agent model for the exploitation of the Arcto-Norwegian cod stock is developed to investigate the economic benefits that can be realized from the resource, and the effect of exploitation on stock sustainability under cooperation and non-cooperation. The two agents are identified in this study as a trawl fishery versus a coastal fishery. Unlike in Munro (1979), where conflicts in the management strategies of agents arise from differences in the perceptions of the discount factor, fishing effort costs, and consumer preferences, here conflicts arise mainly from the differences in fishing gear and grounds, and the age group of cod targeted by the two agents. Using a game theoretic framework, we show that given available data, the optimum optimorum is obtained under cooperation with side payments and no predetermined harvest shares, in which case the coastal fishery buys out the trawl fishery. However, sensitivity analysis shows that if the price premium assumed for mature cod is taken away, the trawl fishery takes over as the producer of the optimum optimorum.     

Dynamic and Comparative Static Analysis of Imperfectly Competitive International Fishery

A dynamic system for change of fish stock is formulated assuming that two asymmetric rival countries harvest fish from a common fishing ground and sell it in an imperfectly competitive market. The existence of a unique stable steady state is examined based on the dynamic system. Comparative static analysis is conducted in relation to changes in national fishing management policies to explore, among other things, rent-shifting from one country to another.     

PRIVATE PROPERTY RIGHTS AND CRISES IN WORLD FISHERIES: TURNING THE TIDE?

This paper addresses the crises in the world's fisheries involving dwindling stocks, overcapitalization, and jurisdiction disputes from a property rights perspective. In particular, it examines the causes of the problems fishers face and explores the potential of privatizing the right to catch fish as a means to address the crises. The analysis assesses experiences of private harvesting rights with reference to monitoring and enforcement, allocating rights, economic benefits, adjustments in the fishery, and resource rents. It also examines issues such as fluctuating fish stocks, straddling stocks and high seas fisheries, and the endemic poverty of many artisanal fisheries in the context of current fisheries practice.     

IUU捕捞对渔业资源的损害及港口国的管制措施分析

IUU捕捞是国际海洋渔业资源的公害。港口国可以通过渔船登陆等措施执行防范、遏制与消除IUU捕捞的渔业政策。IUU导致的后果很严重,甚至可以摧毁整个渔业。从事IUU捕捞行为的人都是不负责任的人,它们无视捕鱼纪律和规则,相对于行为端正的渔业人（也即：按照捕鱼规则作业的渔民）,获得了不公平的竞争优势。     

Economic and conservation implications of a variable effort penalty system in effort-controlled fisheries

Bycatch of threatened, endangered or protected species by commercial fishers is a universal problem. Technical solutions are often applied that may impose inefficiencies across the fleet, even in periods or areas when the risk of bycatch is low. These may include gear specifically designed to avoid the bycatch which may also reduce the targeted catch, or designation of marine protected areas that exclude fishing from whole areas. In this article, we examine the effectiveness of a variable penalty system that can provide incentives for fishers to redirect their effort away from problem areas. The system is examined using a case study of fishery, which is currently subjected to gear and closure controls to limit bycatch of turtles and seabirds. An alternative incentive-based management policy using a series of differential hook penalties has been proposed as a flexible tool to discourage vessels operating in certain areas. The effects of various hook penalties and closures in key areas on fishing effort in those areas and elsewhere as well as vessel economic performance are assessed using a location choice model. The results suggest that incentive-based approaches may result in lower costs to industry than closures provided some level of residual bycatch is acceptable.     

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.     

Individual Rationality and the “Zonal Attachment” Principle: Three Stock Migration Models

Shared fish stocks migrate across borders between different countries’ exclusive economic zones. This paper discusses the individual rationality of fish-sharing agreements based on the zonal attachment of such stocks. Three types of migrations are considered: (i) a common stock that grows and reproduces and is then distributed in given proportions between two countries’ zones at the beginning of each fishing season; (ii) sub-stocks that breed and grow independently in their separate zones but spill over between zones according to relative abundance; (iii) a stock that grows and breeds in one country’s zone but migrates into the zone of another if it exceeds a certain size. It is shown that in all these cases the minor partner in a fish-sharing agreement may not have an incentive to cooperate unless he gets a larger share of the cooperative profits than that corresponds to his share of the stock. This is particularly likely to happen when the unit cost of fish does not depend on the stock. An exception could occur if stock migration depends on the stock level; the major partner could then keep the entire stock by fishing it down to a critical level.     

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.     

Fisheries Management Under Cyclical Population Dynamics

Cycles in environmental conditions (e.g., sea-surface temperature) directly impact fish growth. This paper extends the classical Gordon-Schaefer fishery model by replacing the constant growth rate with a cyclical growth rate. The optimal harvest rate is shown to fluctuate, but the cycle of the harvest rate lags the cycle of the biological growth function with the highest harvest rate occurring after biological conditions start to decline. Simulations contrast various fishing policies and illustrate the proclivity to crash a fishery if it is wrongfully managed as if there is a constant growth rate with i.i.d. environmental shocks. Finally, we show that small cyclical fluctuations in one species can result in large fluctuations in the optimal harvest rate of another species if the fish species are interlinked through predator-prey relationships.      

Transboundary marine protected areas

Countries exploiting transboundary natural resources face strong incentives to over-exploit. This basic economic insight has been validated empirically where numerous resources such as water, forests, game, and fisheries are found to be in worse condition than those completely contained in single nations. Attempts to solve this challenge through cross-country cooperation have been largely unsuccessful because competitive extraction is often more attractive than adhering to cooperative agreements. Focusing on the fishery, we explore the game-theoretic economics of an alternative to cooperative arrangements, called a transboundary marine protected area (TMPA), which straddles both countries’ waters. We derive the conditions under which it can improve profits and stock biomass, even in the presence of individually-rational non-cooperation across countries. Strikingly, we find that well-designed TMPAs have the potential to completely overcome non-cooperation across countries; this result is strongest for low growth rate species. A TMPA can earn higher harvest benefits for both countries, increase stocks in both countries, and in many cases, can even reproduce the fully cooperative outcome.     

Parameter Uncertainty in CGE Modeling of the Environmental Impacts of Economic Policies

Political and economic factors usually determine the harvest sharesallotted to heterogeneous fisher groups harvesting upon the same fishstock. Given that the fishers harvest upon different segments of a fishstock with, for instance, cannibalistic tendencies, the shares allottedmay have considerable effect upon the well-being of the stock and theeconomics of the fishery. This paper analyses an existing allocationrule defining harvest shares allotted to two vessel groups (trawlers andcoastal vessels) in the Norwegian cod fishery. We apply a model with twointeracting age groups within a single fish stock, where the interactionhas both biological and economic implications. Requiring a first bestapproach to an optimal stock size results in no harvest in the firstyears studied. In order to ensure harvest amounts close to the historicharvest, we design a second best model giving optimal biological sharesin the build-up phase of the stock, and bioeconomic optimal shares atthe optimum fish stock level. The second best model recommends that foran increasing stock size the trawlers should obtain decreasing shares.We find that the actual allocation rule functions in a manner oppositeto the second best model, since this rule allocates an increasing shareto the trawlers for an increasing stock size.     

Preference for Landings’ Smoothing and Risk of Collapse in Optimal Fishery Policies: The Ibero-Atlantic Sardine Fishery

Several world fish stocks are being explored at unsustainable levels and require management plans to rebuild stock abundance. Defining a management plan is, however, a complex task that entails multidisciplinary work. In fact, while it requires solid scientific knowledge of fish stocks, the inclusion of economic and social objectives is crucial to a successful management implementation. In this paper we develop an age-structured bioeconomic model where the objective function is modified to accommodate preferences from different stakeholders. In particular, we consider important characteristics that a management plan should take into account: profit maximization, fishermen’s preference for reducing landings’ fluctuations and risk of fishery collapse. Modeling preferences for reducing landings’ fluctuations is accomplished by defining a utility function with aversion to intertemporal income fluctuations. Building upon biology literature, we model precautionary concerns by incorporating a probability of collapse that depends on current spawning biomass. We illustrate how this framework is able to assist in the analysis and design of harvest control rules applying it to the Ibero-Atlantic sardine stock.     

Management of interacting species: regulation under nonlinearities and hysteresis

We consider the optimal regulation of an open access fishery when biomass dynamics are combined with fishing effort dynamics. The interaction of inelastic demand and backward bending nature of the ecological supply curve introduce nonlinearities that could lead to multiple bionomic equilibria and hysteresis effects. We obtain convergence results for general bionomic models and indicate cases where hysteretic regulation failure could be a problem when economic dynamics are slow enough relative to biological dynamics. We show that when biological dynamics are slow enough relative to the economic dynamics, the social optimum can be achieved by a time dependent landing fee.     

Creating Asset Accounts For A Commercial Fishery Out Of Equilibrium: A Case Study Of The Atlantic Sea Scallop Fishery

This paper demonstrates a methodology for constructing asset accounts for a commercial fishery in which the stock, harvest, and effort level are out of sustainable equilibrium. The paper adopts the framework used by the U.S. Department of Commerce Bureau of Economic Analysis in its preliminary 1993 Integrated Economic and Environmental Accounts and follows methodologies recommended by the National Research Council committee constituted to review those efforts. The accounts were constructed for the period 1985 to 1995 for the Atlantic sea scallop fishery, a significant commercial fishery, using information obtained with the cooperation of the National Marine Fisheries Service from existing databases constructed for management purposes. No significant additional data collection was required for the purpose of this study. Differences between the net rent and user cost values of the stocks over this period indicate the inefficient exploitation of immature scallop populations.