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• 1. [Article] Changes in a seafood market: substitution and elasticity of fish categories behavior in SE Brazil

  Poster session.

  Citation × Citation Citation Abstract Copy Title: Changes in a seafood market: substitution and elasticity of fish categories behavior in SE Brazil Author: Gasalla, Maria A., Pincinato, Ruth B. M. Poster session. Title: Changes in a seafood market: substitution and elasticity of fish categories behavior in SE Brazil Author: Gasalla, Maria A., Pincinato, Ruth B. M. Poster session. Close

• 2. [Article] Nutrient Enrichment and Marine Ecosystem Disturbance: A Deterministic and Stochastic Approach

  Pollution of the marine areas that support much of the world's commercial fisheries is regarded as a pressing global environmental problem. One often-cited issue is nutrient enrichment, but this may be ...

  Citation × Citation Citation Abstract Copy Title: Nutrient Enrichment and Marine Ecosystem Disturbance: A Deterministic and Stochastic Approach Author: Knowler, Duncan Year: 2001 Pollution of the marine areas that support much of the world's commercial fisheries is regarded as a pressing global environmental problem. One often-cited issue is nutrient enrichment, but this may be a mixed blessing: it contributes to primary productivity and increases the sustainable fish catch, while simultaneously causing occasional and damaging ecosystem events. Thus, enrichment's aggregate impact on the economic value of fisheries may be ambiguous. This research develops a method for analyzing such problems, using the example of the Black Sea anchovy fishery. Employing a bioeconomic model that incorporates nutrients directly into fish population dynamics, the problem is formulated in deterministic and stochastic terms and the results compared. The deterministic model assumes that nutrients only contribute positively to fish production for a given ecological state, and ignores stochastic events leading to shifts between states. Accordingly, marginal abatement of nutrients leads to annual welfare losses of US$ 45,000 to 713,00 per μ (1989/90 prices), depending upon the ecosystem state. The stochastic formulation recognizes that planners may have some knowledge of potentially damaging shifts in ecological states, and wish to take this into account. When these shifts are related stochastically to the level of enrichment, nutrient abatement is shown to have an indeterminate welfare effect. However, an experimental empirical analysis indicates that a marginal change in nutrients can generate positive and sizeable aggregate benefits for the Black Sea anchovy fishery under certain conditions. The general applicability of such an approach for analyzing a range of marine environmental problems is noted Title: Nutrient Enrichment and Marine Ecosystem Disturbance: A Deterministic and Stochastic Approach Author: Knowler, Duncan Year: 2001 Pollution of the marine areas that support much of the world's commercial fisheries is regarded as a pressing global environmental problem. One often-cited issue is nutrient enrichment, but this may be a mixed blessing: it contributes to primary productivity and increases the sustainable fish catch, while simultaneously causing occasional and damaging ecosystem events. Thus, enrichment's aggregate impact on the economic value of fisheries may be ambiguous. This research develops a method for analyzing such problems, using the example of the Black Sea anchovy fishery. Employing a bioeconomic model that incorporates nutrients directly into fish population dynamics, the problem is formulated in deterministic and stochastic terms and the results compared. The deterministic model assumes that nutrients only contribute positively to fish production for a given ecological state, and ignores stochastic events leading to shifts between states. Accordingly, marginal abatement of nutrients leads to annual welfare losses of US$ 45,000 to 713,00 per μ (1989/90 prices), depending upon the ecosystem state. The stochastic formulation recognizes that planners may have some knowledge of potentially damaging shifts in ecological states, and wish to take this into account. When these shifts are related stochastically to the level of enrichment, nutrient abatement is shown to have an indeterminate welfare effect. However, an experimental empirical analysis indicates that a marginal change in nutrients can generate positive and sizeable aggregate benefits for the Black Sea anchovy fishery under certain conditions. The general applicability of such an approach for analyzing a range of marine environmental problems is noted Close

• 3. [Article] Anticipating the Unintended Consequences of Environmental Management in a Marine Socio-Ecological System using Qualitative Loop Analysis

  presentation

  Citation × Citation Citation Abstract Copy Title: Anticipating the Unintended Consequences of Environmental Management in a Marine Socio-Ecological System using Qualitative Loop Analysis Author: Jennings, Sarah, Austen, Giles presentation Title: Anticipating the Unintended Consequences of Environmental Management in a Marine Socio-Ecological System using Qualitative Loop Analysis Author: Jennings, Sarah, Austen, Giles presentation Close

• 4. [Article] Modelling the Potential Fisheries Impacts on the Trophic Structure of Moreton Bay, Australia

  presentation

  Citation × Citation Citation Abstract Copy Title: Modelling the Potential Fisheries Impacts on the Trophic Structure of Moreton Bay, Australia Author: Chaloupka, Milani, Fondo, Esther, Skilleter, Greg presentation Title: Modelling the Potential Fisheries Impacts on the Trophic Structure of Moreton Bay, Australia Author: Chaloupka, Milani, Fondo, Esther, Skilleter, Greg presentation Close

• 5. [Article] Fisheries and Optimal Eutrophication Management: A Bayesian Approach

  presentation

  Citation × Citation Citation Abstract Copy Title: Fisheries and Optimal Eutrophication Management: A Bayesian Approach Author: Oinonen, Soile, Lindroos, Marko, Peltonen, Heikki, Heikinheimo, Outi, Uusitalo, Laura presentation Title: Fisheries and Optimal Eutrophication Management: A Bayesian Approach Author: Oinonen, Soile, Lindroos, Marko, Peltonen, Heikki, Heikinheimo, Outi, Uusitalo, Laura presentation Close

• 6. [Article] Impacts of Marine Reserves in the Galapagos Islands: Some Considerations

  The recent establishment of the Galápagos Marine Reserve (GMR) presents a unique opportunity to analyze the economic implications of using zonification as a tool to manage conflicting claims to a fragile ...

  Citation × Citation Citation Abstract Copy Title: Impacts of Marine Reserves in the Galapagos Islands: Some Considerations Author: Wilen, James E., Stewart, Micki Year: 2001 The recent establishment of the Galápagos Marine Reserve (GMR) presents a unique opportunity to analyze the economic implications of using zonification as a tool to manage conflicting claims to a fragile and limited resource. Recognizing that the long-term success of the GMR depends on the cooperation of all of the stakeholders involved, a remarkable feature of the new legislation is that further policy development depends upon analysis of the socio-economic and environmental impacts that the new management regime has on both the users and the ecosystems of the GMR. We consider some of the economic impacts to the residents of Galápagos, and in particular to the fisheries sector, resulting from the use of “no take” zones as a management tool. We develop a simple two-sector fixed labor model to illustrate how the establishment of “no take” zones, which impact the fishing sector, will also affect the tourism sector through both the labor market and biotic mechanisms. Although we find that the establishment of marine refugia passes a rough cost-benefit analysis, we discuss the importance of considering the intertemporal nature of the impacts resulting from the closure of fishing grounds in the GMR when analyzing the economic impacts to the various sectors. Title: Impacts of Marine Reserves in the Galapagos Islands: Some Considerations Author: Wilen, James E., Stewart, Micki Year: 2001 The recent establishment of the Galápagos Marine Reserve (GMR) presents a unique opportunity to analyze the economic implications of using zonification as a tool to manage conflicting claims to a fragile and limited resource. Recognizing that the long-term success of the GMR depends on the cooperation of all of the stakeholders involved, a remarkable feature of the new legislation is that further policy development depends upon analysis of the socio-economic and environmental impacts that the new management regime has on both the users and the ecosystems of the GMR. We consider some of the economic impacts to the residents of Galápagos, and in particular to the fisheries sector, resulting from the use of “no take” zones as a management tool. We develop a simple two-sector fixed labor model to illustrate how the establishment of “no take” zones, which impact the fishing sector, will also affect the tourism sector through both the labor market and biotic mechanisms. Although we find that the establishment of marine refugia passes a rough cost-benefit analysis, we discuss the importance of considering the intertemporal nature of the impacts resulting from the closure of fishing grounds in the GMR when analyzing the economic impacts to the various sectors. Close

• 7. [Article] Fisheries and Aquaculture Management Within the Scope of System Approach; A Review of Experiences, Limits and Advantages

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Fisheries and Aquaculture Management Within the Scope of System Approach; A Review of Experiences, Limits and Advantages Author: Mongruel, Rémi, Michel, Lample, Raux, Pascal, Bailly, Denis, Pérez Agúndez, José Antonio, Balle-Beganton, Johanna Abstract only. Title: Fisheries and Aquaculture Management Within the Scope of System Approach; A Review of Experiences, Limits and Advantages Author: Mongruel, Rémi, Michel, Lample, Raux, Pascal, Bailly, Denis, Pérez Agúndez, José Antonio, Balle-Beganton, Johanna Abstract only. Close

• 8. [Article] Incorporating Habitat Dynamics into Bioeconomic Model of Fishery. Application to Artificial Reefs

  In this paper the emphasis is put on an important aspect of renewable resource use that was disregarded until now. It is the evolution of environmental carrying capacity which is traditionally interpreted ...

  Citation × Citation Citation Abstract Copy Title: Incorporating Habitat Dynamics into Bioeconomic Model of Fishery. Application to Artificial Reefs Author: Cartigny, Pierre, Ami, Dominique, Udumyan, Narine In this paper the emphasis is put on an important aspect of renewable resource use that was disregarded until now. It is the evolution of environmental carrying capacity which is traditionally interpreted as a maximal population level that can be supported by the environment (or by habitats of which it consists). Hence we adapt the Gordon-Schaefer model with constant carrying capacity by incorporating time-dependent carrying capacity that determines the state of habitats. They are subject to some biological processes (habitat rehabilitation) as well as to human aggressions (in particular habitat degradation due to fishing). Based on the developed model, we reassess the recommendations considered as a benchmark for resource managers until recently. Under simple hypotheses on the form of habitat (carrying capacity) dynamics, the current study has shown the importance of the latter for the design of management tools. When dynamic patterns of habitats are not taken into account, fishery recommendations based on Gordon-Schaefer model can be aberrant and lead to the collapse of the fishery. The presented model allows not only to enrich the design of management tools but also to assess the performance of artificial reefs, a promising ecosystem-based tool widely used in some coastal areas. The economic benefits of artificial reefs are still not well studied and represent a challenge to take up. Since artificial reefs are conceived as replacement for natural habitats, they assume the same role as these latter. Therefore the structure of our model seems appropriate to evaluate this particular management tool. Title: Incorporating Habitat Dynamics into Bioeconomic Model of Fishery. Application to Artificial Reefs Author: Cartigny, Pierre, Ami, Dominique, Udumyan, Narine In this paper the emphasis is put on an important aspect of renewable resource use that was disregarded until now. It is the evolution of environmental carrying capacity which is traditionally interpreted as a maximal population level that can be supported by the environment (or by habitats of which it consists). Hence we adapt the Gordon-Schaefer model with constant carrying capacity by incorporating time-dependent carrying capacity that determines the state of habitats. They are subject to some biological processes (habitat rehabilitation) as well as to human aggressions (in particular habitat degradation due to fishing). Based on the developed model, we reassess the recommendations considered as a benchmark for resource managers until recently. Under simple hypotheses on the form of habitat (carrying capacity) dynamics, the current study has shown the importance of the latter for the design of management tools. When dynamic patterns of habitats are not taken into account, fishery recommendations based on Gordon-Schaefer model can be aberrant and lead to the collapse of the fishery. The presented model allows not only to enrich the design of management tools but also to assess the performance of artificial reefs, a promising ecosystem-based tool widely used in some coastal areas. The economic benefits of artificial reefs are still not well studied and represent a challenge to take up. Since artificial reefs are conceived as replacement for natural habitats, they assume the same role as these latter. Therefore the structure of our model seems appropriate to evaluate this particular management tool. Close

• 9. [Article] Evaluating the Social Costs of Fishing Activities in A Deliberative Perspective

  The ECOST project aims to develop a new approach for the evaluation of fishing activities and policies in order to contribute to a better management of aquatic resources which affect sustainable development ...

  Citation × Citation Citation Abstract Copy Title: Evaluating the Social Costs of Fishing Activities in A Deliberative Perspective Author: O’Connor, Martin, Failler, Pierre, Johnson, Pierre W., Chamaret, Aurélie, Ferraro, Gianluca, Douguet, Jean-Marc The ECOST project aims to develop a new approach for the evaluation of fishing activities and policies in order to contribute to a better management of aquatic resources which affect sustainable development in coastal zones around the world. It has to be seen from the wider perspective of equipping public decisionmakers and society with the appropriate tools and methods needed to take into account, not only immediate economic and social profits, but also the costs engendered by fishing activities, which relate as much to ecosystems as to societies. The novelty and originality of the suggested approach doesn’t rely on the concept chosen for the analysis, the social cost, but on the way it is built and mobilised to deliberate on the evaluation of fishing activities. As Fisheries activity is a complex system, characterized by reciprocal interactions between fisheries activity and the harvested resource, it is difficult to define the effects of such activities in the society. The social cost is thus defined as an articulation between the frontiers of what is feasible? and the assessment of members of the society concerning what will be judged desirable? (O’Connor 2004). We propose an evaluation process defining the performance issue related to fishery metiers, a set of indicators and a method to assess the social cost using the Kerbabel Deliberation Matrix framework. Title: Evaluating the Social Costs of Fishing Activities in A Deliberative Perspective Author: O’Connor, Martin, Failler, Pierre, Johnson, Pierre W., Chamaret, Aurélie, Ferraro, Gianluca, Douguet, Jean-Marc The ECOST project aims to develop a new approach for the evaluation of fishing activities and policies in order to contribute to a better management of aquatic resources which affect sustainable development in coastal zones around the world. It has to be seen from the wider perspective of equipping public decisionmakers and society with the appropriate tools and methods needed to take into account, not only immediate economic and social profits, but also the costs engendered by fishing activities, which relate as much to ecosystems as to societies. The novelty and originality of the suggested approach doesn’t rely on the concept chosen for the analysis, the social cost, but on the way it is built and mobilised to deliberate on the evaluation of fishing activities. As Fisheries activity is a complex system, characterized by reciprocal interactions between fisheries activity and the harvested resource, it is difficult to define the effects of such activities in the society. The social cost is thus defined as an articulation between the frontiers of what is feasible? and the assessment of members of the society concerning what will be judged desirable? (O’Connor 2004). We propose an evaluation process defining the performance issue related to fishery metiers, a set of indicators and a method to assess the social cost using the Kerbabel Deliberation Matrix framework. Close