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• 1. [Article] A Stochastic Viability Approach for Ecosystem-Based Management of Mixed Fisheries: The Case of The Bay of Biscay Demersal Fisheries

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: A Stochastic Viability Approach for Ecosystem-Based Management of Mixed Fisheries: The Case of The Bay of Biscay Demersal Fisheries Author: Gourguet, Sophie, Doyen, Luc, Thébaud, Olivier, Macher, Claire, Guyader, Olivier Abstract only. Title: A Stochastic Viability Approach for Ecosystem-Based Management of Mixed Fisheries: The Case of The Bay of Biscay Demersal Fisheries Author: Gourguet, Sophie, Doyen, Luc, Thébaud, Olivier, Macher, Claire, Guyader, Olivier Abstract only. Close

• 2. [Article] Towards Behavioural Models of Fleet Dynamics

  Considerable attention has been applied to the development of models explaining how fish stocks change over space and time, from relatively simple stock-recruitment relationships to ecosystem models with ...

  Citation × Citation Citation Abstract Copy Title: Towards Behavioural Models of Fleet Dynamics Author: Hamon, Katell G., Kulmala, Soile, Thébaud, Olivier, Van Putten, Ingrid, Hutton, Trevor, Dowling, Natalie, Pascoe, Sean Considerable attention has been applied to the development of models explaining how fish stocks change over space and time, from relatively simple stock-recruitment relationships to ecosystem models with a complex food web structure. However, in many case studies fishing effort is assumed to be exogenous and even in dynamic models pre-determined by external factors such as management. An increasing number of operational bio-economic models for the marine environment are including a fleet dynamics component, recognising that fishers respond to changing environmental and economic conditions. These models are based on different assumptions about behaviour. In this review, we examine models of fisher behaviour that are empirically or theoretically developed and tested. In particular, we focus on the range of different economic and social drivers and their relevance to different types of behaviour. We find that economic factors are a dominant driver included in many types of short term behavioural models, although we acknowledge and find that other social factors play a significant role in some types of behaviour. The link between management and economic impacts is reasonably well established, and most bioeconomic models are able to incorporate these feedback systems. Incorporating these other social-dependent behaviours into bioeconomic models, however, is likely to remain a challenge unless links between management and changes in the social drivers are developed. Title: Towards Behavioural Models of Fleet Dynamics Author: Hamon, Katell G., Kulmala, Soile, Thébaud, Olivier, Van Putten, Ingrid, Hutton, Trevor, Dowling, Natalie, Pascoe, Sean Considerable attention has been applied to the development of models explaining how fish stocks change over space and time, from relatively simple stock-recruitment relationships to ecosystem models with a complex food web structure. However, in many case studies fishing effort is assumed to be exogenous and even in dynamic models pre-determined by external factors such as management. An increasing number of operational bio-economic models for the marine environment are including a fleet dynamics component, recognising that fishers respond to changing environmental and economic conditions. These models are based on different assumptions about behaviour. In this review, we examine models of fisher behaviour that are empirically or theoretically developed and tested. In particular, we focus on the range of different economic and social drivers and their relevance to different types of behaviour. We find that economic factors are a dominant driver included in many types of short term behavioural models, although we acknowledge and find that other social factors play a significant role in some types of behaviour. The link between management and economic impacts is reasonably well established, and most bioeconomic models are able to incorporate these feedback systems. Incorporating these other social-dependent behaviours into bioeconomic models, however, is likely to remain a challenge unless links between management and changes in the social drivers are developed. Close

• 3. [Article] Tragedy of the Commons and International Trade: Case of International Fisheries

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Tragedy of the Commons and International Trade: Case of International Fisheries Author: Takarada, Yasuhiro, Fujii, Takamune Abstract only. Title: Tragedy of the Commons and International Trade: Case of International Fisheries Author: Takarada, Yasuhiro, Fujii, Takamune Abstract only. Close

• 4. [Article] Economics of the Recovery of Fish Stocks: Comparison of A Npv Calculation of A Recovery Strategy With the Real Development of the Baltic Cod Fishery

  The recovery of fish stocks is in principle an investment decision weighing up short term losses against future gains. In the Common Fisheries Policy (CFP) of the EU long term management or recovery plans are ...

  Citation × Citation Citation Abstract Copy Title: Economics of the Recovery of Fish Stocks: Comparison of A Npv Calculation of A Recovery Strategy With the Real Development of the Baltic Cod Fishery Author: Berkenhagen, Jörg, Döring, Ralf The recovery of fish stocks is in principle an investment decision weighing up short term losses against future gains. In the Common Fisheries Policy (CFP) of the EU long term management or recovery plans are a main instrument. One of the basic aims is to move from a short term to a longer term perspective in the management process by having automatic rules about how to set quotas in the following years. This gives fishermen more security on catch possibilities in the future. However, it is not clear whether measures in recovery plans are economically feasible or not. Fishermen may lose more than they gain from such a recovery plan. In the first part of the paper we describe the economics behind long term management plans and the rationale of such plans from an economic viewpoint. Secondly, we use the Baltic cod fishery as an example to compare the present value of recovery scenarios and a status quo scenario. As a simplification only one cod stock is assumed in that calculation (in the Baltic Sea a western and eastern stock are distinguished). In the meantime a long term management plan for Baltic cod is in place since 2008. Especially the Eastern stock shows strong signs of recovery because of reduced fishing effort and good recruitment. In a third part we analyze to which extent the general calculations are comparable to the experiences in the real fishery. Title: Economics of the Recovery of Fish Stocks: Comparison of A Npv Calculation of A Recovery Strategy With the Real Development of the Baltic Cod Fishery Author: Berkenhagen, Jörg, Döring, Ralf The recovery of fish stocks is in principle an investment decision weighing up short term losses against future gains. In the Common Fisheries Policy (CFP) of the EU long term management or recovery plans are a main instrument. One of the basic aims is to move from a short term to a longer term perspective in the management process by having automatic rules about how to set quotas in the following years. This gives fishermen more security on catch possibilities in the future. However, it is not clear whether measures in recovery plans are economically feasible or not. Fishermen may lose more than they gain from such a recovery plan. In the first part of the paper we describe the economics behind long term management plans and the rationale of such plans from an economic viewpoint. Secondly, we use the Baltic cod fishery as an example to compare the present value of recovery scenarios and a status quo scenario. As a simplification only one cod stock is assumed in that calculation (in the Baltic Sea a western and eastern stock are distinguished). In the meantime a long term management plan for Baltic cod is in place since 2008. Especially the Eastern stock shows strong signs of recovery because of reduced fishing effort and good recruitment. In a third part we analyze to which extent the general calculations are comparable to the experiences in the real fishery. Close

• 5. [Article] Uncertainty and Risk in the Ecosystems Approach to Fisheries Management: Some Insights from an Ecosystem Computer Simulation Model

  Understanding the complexities of ecosystems is difficult enough, but when the human dimension is added to the inherent uncertainty and risk in fisheries management, the actual versus expected results ...

  Citation × Citation Citation Abstract Copy Title: Uncertainty and Risk in the Ecosystems Approach to Fisheries Management: Some Insights from an Ecosystem Computer Simulation Model Author: Ward, John, Metzner, Rebecca, DeYoung, Cassandra Understanding the complexities of ecosystems is difficult enough, but when the human dimension is added to the inherent uncertainty and risk in fisheries management, the actual versus expected results move from the counter-intuitive to the paradoxical. Without an adequate understanding of the interrelationships between ecosystem components, including the human dimension, scientific management becomes intuition-based management, which is often counterproductive to achieving desired goals and objectives. A computer simulation model is developed for multiple species, resource areas, stocks, and cohorts. To explicitly incorporate ecosystem effects predator-prey and competitor relationships are constructed to interpret interactions between different species of fish. Fishing fleet dynamics are captured by modeling multiple vessel classes based on specifications for catchability and concentration profiles. Additional uncertainty is included through the effects of market supply and demand on price for different discount rates. Economic impacts are also estimated for each point in time as biological and market conditions change. This simulation model results are then compared to determine if the management objective of maximization of net benefits subject to the fish stock conservation goal are achievable in an ecosystem context while also considering impacts on jobs, income, and sales. Insights from this simulation of an ecosystem should provide information on the needed research required for the ecosystem approach to fisheries management to be successful in achieving its multiple objectives. Title: Uncertainty and Risk in the Ecosystems Approach to Fisheries Management: Some Insights from an Ecosystem Computer Simulation Model Author: Ward, John, Metzner, Rebecca, DeYoung, Cassandra Understanding the complexities of ecosystems is difficult enough, but when the human dimension is added to the inherent uncertainty and risk in fisheries management, the actual versus expected results move from the counter-intuitive to the paradoxical. Without an adequate understanding of the interrelationships between ecosystem components, including the human dimension, scientific management becomes intuition-based management, which is often counterproductive to achieving desired goals and objectives. A computer simulation model is developed for multiple species, resource areas, stocks, and cohorts. To explicitly incorporate ecosystem effects predator-prey and competitor relationships are constructed to interpret interactions between different species of fish. Fishing fleet dynamics are captured by modeling multiple vessel classes based on specifications for catchability and concentration profiles. Additional uncertainty is included through the effects of market supply and demand on price for different discount rates. Economic impacts are also estimated for each point in time as biological and market conditions change. This simulation model results are then compared to determine if the management objective of maximization of net benefits subject to the fish stock conservation goal are achievable in an ecosystem context while also considering impacts on jobs, income, and sales. Insights from this simulation of an ecosystem should provide information on the needed research required for the ecosystem approach to fisheries management to be successful in achieving its multiple objectives. Close

• 6. [Article] Fishing Capacity of Georgian Anchovy Fishery

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Fishing Capacity of Georgian Anchovy Fishery Author: Bilashvili, Kakhaber, García del Hoyo, Juan José, Castilla Espino, David, Metreveli, Maya Abstract only. Title: Fishing Capacity of Georgian Anchovy Fishery Author: Bilashvili, Kakhaber, García del Hoyo, Juan José, Castilla Espino, David, Metreveli, Maya Abstract only. Close

• 7. [Article] Fishery Management When Biological and Economic Disturbances Are Correlated

  Economists studying the management of fisheries have universally assumed disturbances affecting harvest costs are unrelated to disturbances affecting biological growth. This paper gives examples of commercially ...

  Citation × Citation Citation Abstract Copy Title: Fishery Management When Biological and Economic Disturbances Are Correlated Author: Kennedy, Chris J. Economists studying the management of fisheries have universally assumed disturbances affecting harvest costs are unrelated to disturbances affecting biological growth. This paper gives examples of commercially valuable species that are impacted reproductively and behaviorally by a single environmental variable (e.g., temperature), leading to correlated disturbances in current marginal harvest costs and future biological growth. A general analytical model examines the importance of considering correlated disturbances when choosing optimal escapement targets, and shows how the presence of correlation affects the value of waiting for information on harvest costs. These results give insight as to the appropriate use of "self-correcting" mechanisms for controlling harvest, such as landing fees, versus hard targets, and provide a framework for proactive management of fisheries in the face of large-scale marine disturbances that can affect both the biological growth and behavior of commercially valuable species. Title: Fishery Management When Biological and Economic Disturbances Are Correlated Author: Kennedy, Chris J. Economists studying the management of fisheries have universally assumed disturbances affecting harvest costs are unrelated to disturbances affecting biological growth. This paper gives examples of commercially valuable species that are impacted reproductively and behaviorally by a single environmental variable (e.g., temperature), leading to correlated disturbances in current marginal harvest costs and future biological growth. A general analytical model examines the importance of considering correlated disturbances when choosing optimal escapement targets, and shows how the presence of correlation affects the value of waiting for information on harvest costs. These results give insight as to the appropriate use of "self-correcting" mechanisms for controlling harvest, such as landing fees, versus hard targets, and provide a framework for proactive management of fisheries in the face of large-scale marine disturbances that can affect both the biological growth and behavior of commercially valuable species. Close

• 8. [Article] Estimating A Supply Function for the Galician Fleet in the Celtic Sea Fishery

  The aim of this work is to estimate the supply elasticity of the fish regarding the variationsin one of the most important running costs (fuel cost) for the Galician fleet in the Celtic Sea. The Spanish ...

  Citation × Citation Citation Abstract Copy Title: Estimating A Supply Function for the Galician Fleet in the Celtic Sea Fishery Author: Pérez-Pérez, Marcos, Varela-Lafuente, Manuel M., Torralba-Cano, Julia, Garza-Gil, M. Dolores The aim of this work is to estimate the supply elasticity of the fish regarding the variationsin one of the most important running costs (fuel cost) for the Galician fleet in the Celtic Sea. The Spanish fleet involved in the Celtic Sea fishing grounds, also known as the _300 fleet_, as when Spain joined the EEC it was made up of this number of vessels, presently has 199 vessels (the 70% of them operate from Galicia).This fleet mainly catches hake (merlucius merlucius), anglerfish (Lophius piscatorius and Lophius budegassa), horse mackerel (trauchurus trauchurus), megrim (Lepidorhombus whiffiagonis) and nephrops. Although it is currently possible to associate specific target species with particular fleets, various quantities of hake, anglerfish, megrim and nephrops are taken together, depending on the gear type. A supply function for each species has been estimated as an expression that depends on the price of fish, price of other fish landed by the fleet and the fuel price. The preliminary results indicate that the supply of some species is more elastic regarding the fluctuations in fuel prices than other ones. It could explain the strategy of the fleet for selecting the less elastic stocks to the fuel costs. Title: Estimating A Supply Function for the Galician Fleet in the Celtic Sea Fishery Author: Pérez-Pérez, Marcos, Varela-Lafuente, Manuel M., Torralba-Cano, Julia, Garza-Gil, M. Dolores The aim of this work is to estimate the supply elasticity of the fish regarding the variationsin one of the most important running costs (fuel cost) for the Galician fleet in the Celtic Sea. The Spanish fleet involved in the Celtic Sea fishing grounds, also known as the _300 fleet_, as when Spain joined the EEC it was made up of this number of vessels, presently has 199 vessels (the 70% of them operate from Galicia).This fleet mainly catches hake (merlucius merlucius), anglerfish (Lophius piscatorius and Lophius budegassa), horse mackerel (trauchurus trauchurus), megrim (Lepidorhombus whiffiagonis) and nephrops. Although it is currently possible to associate specific target species with particular fleets, various quantities of hake, anglerfish, megrim and nephrops are taken together, depending on the gear type. A supply function for each species has been estimated as an expression that depends on the price of fish, price of other fish landed by the fleet and the fuel price. The preliminary results indicate that the supply of some species is more elastic regarding the fluctuations in fuel prices than other ones. It could explain the strategy of the fleet for selecting the less elastic stocks to the fuel costs. Close

• 9. [Article] The Norwegian Winter Herring Fishery: A Story Technological Progress and Collapse

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: The Norwegian Winter Herring Fishery: A Story Technological Progress and Collapse Author: Gordon, Daniel, Hannesson, Rögnvaldur Abstract only. Title: The Norwegian Winter Herring Fishery: A Story Technological Progress and Collapse Author: Gordon, Daniel, Hannesson, Rögnvaldur Abstract only. Close

• 10. [Article] Addressing the Distribution of Bio-Economic Impacts of Management Measures Between Fleets: the Case of the Demersal Fisheries in the Bay of Biscay

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Addressing the Distribution of Bio-Economic Impacts of Management Measures Between Fleets: the Case of the Demersal Fisheries in the Bay of Biscay Author: Fresard, Marjolaine, Merzéréaud, Mathieu, Le Grand, Christelle, Macher, Claire, Bertignac, Michel, Guyader, Olivier, Daures, Fabienne, Fifas, Spyros, Le Corre, Lanwenn Abstract only. Title: Addressing the Distribution of Bio-Economic Impacts of Management Measures Between Fleets: the Case of the Demersal Fisheries in the Bay of Biscay Author: Fresard, Marjolaine, Merzéréaud, Mathieu, Le Grand, Christelle, Macher, Claire, Bertignac, Michel, Guyader, Olivier, Daures, Fabienne, Fifas, Spyros, Le Corre, Lanwenn Abstract only. Close