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• 1. [Article] The cost of fisheries induced evolution. An example using data for North-East Atlantic cod

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: The cost of fisheries induced evolution. An example using data for North-East Atlantic cod Author: Reithe, Siv Abstract only. Title: The cost of fisheries induced evolution. An example using data for North-East Atlantic cod Author: Reithe, Siv Abstract only. Close

• 2. [Article] Growth Overfishing

  Growth overfishing squanders large parts of the potential rents in fisheries. Many of today’s fisheries are characterized by a severely truncated age-distribution, which in addition may have irreversible ...

  Citation × Citation Citation Abstract Copy Title: Growth Overfishing Author: Diekert, Florian K. Growth overfishing squanders large parts of the potential rents in fisheries. Many of today’s fisheries are characterized by a severely truncated age-distribution, which in addition may have irreversible ecological consequences. Nevertheless, the implications of age-differentiated harvesting for management have received surprisingly little attention in the literature. In the present paper, optimal and non-cooperative exploitation paths for a generic age-distributed resource are derived. We show that, in the case of perfect selectivity, competition between two agents is sufficient to dissipate all rents. Akin to the classical Bertrand competition in prices, each agent has an incentive to target fish at a younger age. That is, the “race to fish” extends to the dimension of age. This observation is crucial also with respect to management: Individual quotas are not able to restore efficiency unless accompanied by gear regulation. Moreover, it turns out that quotas specified in terms of numbers are far superior to those specified in terms of volume or value. Title: Growth Overfishing Author: Diekert, Florian K. Growth overfishing squanders large parts of the potential rents in fisheries. Many of today’s fisheries are characterized by a severely truncated age-distribution, which in addition may have irreversible ecological consequences. Nevertheless, the implications of age-differentiated harvesting for management have received surprisingly little attention in the literature. In the present paper, optimal and non-cooperative exploitation paths for a generic age-distributed resource are derived. We show that, in the case of perfect selectivity, competition between two agents is sufficient to dissipate all rents. Akin to the classical Bertrand competition in prices, each agent has an incentive to target fish at a younger age. That is, the “race to fish” extends to the dimension of age. This observation is crucial also with respect to management: Individual quotas are not able to restore efficiency unless accompanied by gear regulation. Moreover, it turns out that quotas specified in terms of numbers are far superior to those specified in terms of volume or value. Close

• 3. [Article] Fisheries induced evolution. A review

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Fisheries induced evolution. A review Author: Primicerio, Raul, Reithe, Siv Abstract only. Title: Fisheries induced evolution. A review Author: Primicerio, Raul, Reithe, Siv Abstract only. Close

• 4. [Article] Appreciating the value of age: An evaluation of efficiency gains from controlling gear selectivity under various scenarios

  Abstract only

  Citation × Citation Citation Abstract Copy Title: Appreciating the value of age: An evaluation of efficiency gains from controlling gear selectivity under various scenarios Author: Diekert, Florian Abstract only Title: Appreciating the value of age: An evaluation of efficiency gains from controlling gear selectivity under various scenarios Author: Diekert, Florian Abstract only Close

• 5. [Article] Age-Structured Ecological-Economic Multi-Species Models for Baltic Sea Fisheries

  Abstract Only

  Citation × Citation Citation Abstract Copy Title: Age-Structured Ecological-Economic Multi-Species Models for Baltic Sea Fisheries Author: Quaas, Martin Abstract Only Title: Age-Structured Ecological-Economic Multi-Species Models for Baltic Sea Fisheries Author: Quaas, Martin Abstract Only Close

• 6. [Article] The Spawners' Shadow price: Joint Production of Recruitment and Growth in Agestructured Fish Populations

  Abstract Only

  Citation × Citation Citation Abstract Copy Title: The Spawners' Shadow price: Joint Production of Recruitment and Growth in Agestructured Fish Populations Author: Voss, Rudi, Quaas, Martin Abstract Only Title: The Spawners' Shadow price: Joint Production of Recruitment and Growth in Agestructured Fish Populations Author: Voss, Rudi, Quaas, Martin Abstract Only Close

• 7. [Article] Age, Period, of Birth Cohort: What Determines Demographic Differences in Seafood Consumption?

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Age, Period, of Birth Cohort: What Determines Demographic Differences in Seafood Consumption? Author: Lund, Eiliv, Trondsen, Torbjorn, Scholderer, Joachim Research Paper Title: Age, Period, of Birth Cohort: What Determines Demographic Differences in Seafood Consumption? Author: Lund, Eiliv, Trondsen, Torbjorn, Scholderer, Joachim Research Paper Close

• 8. [Article] Optimal Management of the Baltic Sea Fishery Under Climate Change: An Ecological-Economic Age-Structured Multi-Species Model Analysis

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Optimal Management of the Baltic Sea Fishery Under Climate Change: An Ecological-Economic Age-Structured Multi-Species Model Analysis Author: Voss, Rüdiger, Neuenfeldt, Stefan, Quaas, Martin F., Schmidt, Jörn O. Abstract only. Title: Optimal Management of the Baltic Sea Fishery Under Climate Change: An Ecological-Economic Age-Structured Multi-Species Model Analysis Author: Voss, Rüdiger, Neuenfeldt, Stefan, Quaas, Martin F., Schmidt, Jörn O. Abstract only. Close

• 9. [Article] Determining Optimal Catch in Age-Structural Multispecies Fisheries

  This study investigates optimal catch of Barents Sea stocks, namely Northeast Arctic Cod and Capelin in multispecies ecosystem. We solve a multispecies age structured bioeconomic model for predator-prey ...

  Citation × Citation Citation Abstract Copy Title: Determining Optimal Catch in Age-Structural Multispecies Fisheries Author: Steinshamn, Stein Ivar, Poudel, Diwakar This study investigates optimal catch of Barents Sea stocks, namely Northeast Arctic Cod and Capelin in multispecies ecosystem. We solve a multispecies age structured bioeconomic model for predator-prey interaction. Barents Sea stock data from ICES are employed for model application. Among others, we also include sustainability constraint in the model that contributes towards ecosystem based management of fishery. Our preliminary result suggests that a conservative harvest is optimal for capelin compared to the single species model and a higher harvest is possible in cod in multispecies model. Furthermore, we found that a pulse fishing yields higher value in cod (predator) compared to the uniform (current) fishing policy. Title: Determining Optimal Catch in Age-Structural Multispecies Fisheries Author: Steinshamn, Stein Ivar, Poudel, Diwakar This study investigates optimal catch of Barents Sea stocks, namely Northeast Arctic Cod and Capelin in multispecies ecosystem. We solve a multispecies age structured bioeconomic model for predator-prey interaction. Barents Sea stock data from ICES are employed for model application. Among others, we also include sustainability constraint in the model that contributes towards ecosystem based management of fishery. Our preliminary result suggests that a conservative harvest is optimal for capelin compared to the single species model and a higher harvest is possible in cod in multispecies model. Furthermore, we found that a pulse fishing yields higher value in cod (predator) compared to the uniform (current) fishing policy. Close

• 10. [Article] Contribution of Children in Artisanal Fisheries to Households’ Poverty Alleviation in Ondo State, Nigeria

  Despite the global clamour for the eradication of child labour in agriculture, children in developing countries continue to be prominent actors in the fisheries sector though their contribution is unrecorded ...

  Citation × Citation Citation Abstract Copy Title: Contribution of Children in Artisanal Fisheries to Households’ Poverty Alleviation in Ondo State, Nigeria Author: Mafimisebi, Taiwo Ejiola, Fasina, Oluwatosin Despite the global clamour for the eradication of child labour in agriculture, children in developing countries continue to be prominent actors in the fisheries sector though their contribution is unrecorded in the national income accounts of many countries. The study examined the involvement of children in artisanal fisheries in Ondo State, Nigeria. Simple random sampling procedure was used to select 90 children aged 9-18 years who were involved in artisanal fishing activities. Descriptive statistics were used to present the data gathered for the study. Pearson Product Moment Correlation and the Chi-Square analysis were used to test the study hypotheses at the 0.05 level of significance. Respondents were mostly males (70%) with mean age of 15 ± 2 years. Fishing experience for two-thirds was over 7 years. Major economic activities engaged in by children were fishing (100.0%) and fish marketing (97.8%). All respondents fished more on rivers, lakes, creeks and canals with friends mostly in the mornings (70.0%) between 4-5am (43.3%). Mean daily catch per caput per day amounted in monetary terms to N317. Income increased significantly with age of children (r = 0.27, p< 0.05). Respondents’ major constraint was lack of capital to purchase nets and boats of their own (97.8%). Sustainable involvement of children in artisanal fisheries can help alleviate poverty as the children remitted their incomes to their parents for food, school fees or other school needs. Children’s capacity for production can be boosted through capacity building and greater access to fishing equipment and capital assets used in fishing. Scholarship programmes should be put in place to encourage children who do well at both school and fishing to further develop the quality of future manpower available for fishing in the coastal areas. Title: Contribution of Children in Artisanal Fisheries to Households’ Poverty Alleviation in Ondo State, Nigeria Author: Mafimisebi, Taiwo Ejiola, Fasina, Oluwatosin Despite the global clamour for the eradication of child labour in agriculture, children in developing countries continue to be prominent actors in the fisheries sector though their contribution is unrecorded in the national income accounts of many countries. The study examined the involvement of children in artisanal fisheries in Ondo State, Nigeria. Simple random sampling procedure was used to select 90 children aged 9-18 years who were involved in artisanal fishing activities. Descriptive statistics were used to present the data gathered for the study. Pearson Product Moment Correlation and the Chi-Square analysis were used to test the study hypotheses at the 0.05 level of significance. Respondents were mostly males (70%) with mean age of 15 ± 2 years. Fishing experience for two-thirds was over 7 years. Major economic activities engaged in by children were fishing (100.0%) and fish marketing (97.8%). All respondents fished more on rivers, lakes, creeks and canals with friends mostly in the mornings (70.0%) between 4-5am (43.3%). Mean daily catch per caput per day amounted in monetary terms to N317. Income increased significantly with age of children (r = 0.27, p< 0.05). Respondents’ major constraint was lack of capital to purchase nets and boats of their own (97.8%). Sustainable involvement of children in artisanal fisheries can help alleviate poverty as the children remitted their incomes to their parents for food, school fees or other school needs. Children’s capacity for production can be boosted through capacity building and greater access to fishing equipment and capital assets used in fishing. Scholarship programmes should be put in place to encourage children who do well at both school and fishing to further develop the quality of future manpower available for fishing in the coastal areas. Close

• 11. [Article] Participation in Vessel Buyback Programs: An Option Value Model of the Vessel-Scrapping Decision

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Participation in Vessel Buyback Programs: An Option Value Model of the Vessel-Scrapping Decision Author: Chen, Chin-Chen, Lee, Yao-Hsien, Ching-Ta, Chung Research Paper Title: Participation in Vessel Buyback Programs: An Option Value Model of the Vessel-Scrapping Decision Author: Chen, Chin-Chen, Lee, Yao-Hsien, Ching-Ta, Chung Research Paper Close

• 12. [Article] An Ecological-Economic Simulation Model of Genetic interaction Between Farmed and Wild Salmon

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: An Ecological-Economic Simulation Model of Genetic interaction Between Farmed and Wild Salmon Author: Hindar, Kjetil, Liu, Yajie, Skonhoft, Anders, Diserud, Ola Abstract only. Title: An Ecological-Economic Simulation Model of Genetic interaction Between Farmed and Wild Salmon Author: Hindar, Kjetil, Liu, Yajie, Skonhoft, Anders, Diserud, Ola Abstract only. Close

• 13. [Article] Generalization of Age-Structured Models in Theory and Practice

  A generalization of the harvesting functions and the stock updating functions in age-structured bioeconomic models is outlined. Using this generalization everything from completely uniformly distributed ...

  Citation × Citation Citation Abstract Copy Title: Generalization of Age-Structured Models in Theory and Practice Author: Steinshamn, Stein Ivar A generalization of the harvesting functions and the stock updating functions in age-structured bioeconomic models is outlined. Using this generalization everything from completely uniformly distributed fish to extreme schooling is taken care of. The classical Beverton-Holt model comes out as a special case of the generalized model. Both the theoretical outline as well as practical numerical examples are provided, and the generalization can be applied both for simulation as well as optimization purposes given appropriate software. Here we apply advanced non-linear programming to maximize the net present value in a bioeconomic setting where the new updating and harvesting functions are used as constraints. This is possible thanks to new software, such as KNITRO, for solving highly nonlinear problems. Applications of this generalized model produce interesting new results. One such practical result is that pulse fishing seems to become less and less economically profitable as we move from uniformly distributed fish to schooling species. The main reason why pulse fishing cease to be optimal in schooling fisheries, is that the economies of scale present in search fisheries gradually disappear when we move from search fisheries to schooling fisheries. This may have important implications for how fish stocks ought to be managed in the future, especially with respect to total allowable catches based on bioeconomic criteria. Title: Generalization of Age-Structured Models in Theory and Practice Author: Steinshamn, Stein Ivar A generalization of the harvesting functions and the stock updating functions in age-structured bioeconomic models is outlined. Using this generalization everything from completely uniformly distributed fish to extreme schooling is taken care of. The classical Beverton-Holt model comes out as a special case of the generalized model. Both the theoretical outline as well as practical numerical examples are provided, and the generalization can be applied both for simulation as well as optimization purposes given appropriate software. Here we apply advanced non-linear programming to maximize the net present value in a bioeconomic setting where the new updating and harvesting functions are used as constraints. This is possible thanks to new software, such as KNITRO, for solving highly nonlinear problems. Applications of this generalized model produce interesting new results. One such practical result is that pulse fishing seems to become less and less economically profitable as we move from uniformly distributed fish to schooling species. The main reason why pulse fishing cease to be optimal in schooling fisheries, is that the economies of scale present in search fisheries gradually disappear when we move from search fisheries to schooling fisheries. This may have important implications for how fish stocks ought to be managed in the future, especially with respect to total allowable catches based on bioeconomic criteria. Close

• 14. [Article] Viability of Transboundary Fisheries and International Quota Sharing

  This paper examines the viability of the management of a transboundary resource, the Bay of Biscay anchovy (Engraulis encrasicolus L.). A deterministic model is used to simulate the anchovy dynamics, with ...

  Citation × Citation Citation Abstract Copy Title: Viability of Transboundary Fisheries and International Quota Sharing Author: Curtin, Richard, Martinet, Vincent This paper examines the viability of the management of a transboundary resource, the Bay of Biscay anchovy (Engraulis encrasicolus L.). A deterministic model is used to simulate the anchovy dynamics, with the fish stock consisting of two age groups, “young" and “old", while recruitment follows a Beverton Holt pattern. Two countries, France and Spain, harvest the resource, with two different types of gear, the purse seiner for Spain and the pelagic trawler for France. These technologies impact the different age-groups of anchovy at differing rates. A regulatory agency defines an annual fishing quota and its allocation between the two countries, with the aim of sustainability in the overall allocation design. A set of constraints is defined to describe the sustainability of the system which encompasses the economic, ecological and social aspects of the fishery. The optimal harvest share between the two countries is found and a number of scenarios are then tested in relation to their ability to remain within the set of constraints, or viability kernel. Other scenarios, including the historical trajectory, the optimal harvest share trajectory and the minimum time of crisis trajectory, are examined. Title: Viability of Transboundary Fisheries and International Quota Sharing Author: Curtin, Richard, Martinet, Vincent This paper examines the viability of the management of a transboundary resource, the Bay of Biscay anchovy (Engraulis encrasicolus L.). A deterministic model is used to simulate the anchovy dynamics, with the fish stock consisting of two age groups, “young" and “old", while recruitment follows a Beverton Holt pattern. Two countries, France and Spain, harvest the resource, with two different types of gear, the purse seiner for Spain and the pelagic trawler for France. These technologies impact the different age-groups of anchovy at differing rates. A regulatory agency defines an annual fishing quota and its allocation between the two countries, with the aim of sustainability in the overall allocation design. A set of constraints is defined to describe the sustainability of the system which encompasses the economic, ecological and social aspects of the fishery. The optimal harvest share between the two countries is found and a number of scenarios are then tested in relation to their ability to remain within the set of constraints, or viability kernel. Other scenarios, including the historical trajectory, the optimal harvest share trajectory and the minimum time of crisis trajectory, are examined. Close

• 15. [Article] Market-Based Size Selection in the Bering Sea Pollock Fishery

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Market-Based Size Selection in the Bering Sea Pollock Fishery Author: Haynie, Alan, Ianelli, James Abstract only. Title: Market-Based Size Selection in the Bering Sea Pollock Fishery Author: Haynie, Alan, Ianelli, James Abstract only. Close

• 16. [Article] From Shark Fin Markets to Shark Populations: An Integrated Market Preference Cohort Analysis Of the Blacktip Shark (Carcharhinus limbatus)

  The increasing demand for shark fins in Asia and the shark s life history pattern of slow growth, late maturity, and few offspring, have generated concerns regarding the sustainability of shark resources. ...

  Citation × Citation Citation Abstract Copy Title: From Shark Fin Markets to Shark Populations: An Integrated Market Preference Cohort Analysis Of the Blacktip Shark (Carcharhinus limbatus) Author: Fong, Quentin S.W., Anderson, James L. Year: 2001 The increasing demand for shark fins in Asia and the shark s life history pattern of slow growth, late maturity, and few offspring, have generated concerns regarding the sustainability of shark resources. Despite this concern, little effort has been spent on understanding the markets for shark fin products and the population dynamics of sharks. This work incorporates the results of a conjoint analysis of dried processed shark fins from Hong Kong into a cohort model of the balcktip shark with the objective of maximizing the utility of Hong Kong shark fin importers/processors. Results show that optimal harvest sizes and ages for all mortality and discount factor scenarios are greater than the maturation sizes and ages for both male and female blacktip. Policy implications for this study are also discussed. Title: From Shark Fin Markets to Shark Populations: An Integrated Market Preference Cohort Analysis Of the Blacktip Shark (Carcharhinus limbatus) Author: Fong, Quentin S.W., Anderson, James L. Year: 2001 The increasing demand for shark fins in Asia and the shark s life history pattern of slow growth, late maturity, and few offspring, have generated concerns regarding the sustainability of shark resources. Despite this concern, little effort has been spent on understanding the markets for shark fin products and the population dynamics of sharks. This work incorporates the results of a conjoint analysis of dried processed shark fins from Hong Kong into a cohort model of the balcktip shark with the objective of maximizing the utility of Hong Kong shark fin importers/processors. Results show that optimal harvest sizes and ages for all mortality and discount factor scenarios are greater than the maturation sizes and ages for both male and female blacktip. Policy implications for this study are also discussed. Close

• 17. [Article] The Stability of Rent Maximization in the Western and Central Pacific Fishery

  The potential for achieving sustainable and efficient harvesting of three species of migratory tuna in the Western and Central Pacific Ocean is examined. The stocks reside in exclusive economic zones (mainly ...

  Citation × Citation Citation Abstract Copy Title: The Stability of Rent Maximization in the Western and Central Pacific Fishery Author: Kennedy, John, Hannesson, Rögnvaldur The potential for achieving sustainable and efficient harvesting of three species of migratory tuna in the Western and Central Pacific Ocean is examined. The stocks reside in exclusive economic zones (mainly those of Pacific island countries) and in the high seas. Most harvesting is carried out by distant water fishing nations, including the USA, Japan, Taiwan, China and Korea. Problems of achieving sustainability and efficiency in the harvesting of the stocks by disparate countries are made more difficult due to changes in the harvesting levels of one fleet affecting the rents of another fleet through changes in the age distribution of stock. These types of problem are under review by the Western and Central Pacific Fisheries Commission. Results from an age-structured steady-state bioeconomic model are used to show: the changes in fleet rents and catches of tuna if all fleets form a cooperative grand coalition to deploy fishing effort to maximize rents over the region; the likely non-stability of the grand coalition; and the inferior Nash Equilibria outcomes if fleets fish non-cooperatively to maximize their own rents. Title: The Stability of Rent Maximization in the Western and Central Pacific Fishery Author: Kennedy, John, Hannesson, Rögnvaldur The potential for achieving sustainable and efficient harvesting of three species of migratory tuna in the Western and Central Pacific Ocean is examined. The stocks reside in exclusive economic zones (mainly those of Pacific island countries) and in the high seas. Most harvesting is carried out by distant water fishing nations, including the USA, Japan, Taiwan, China and Korea. Problems of achieving sustainability and efficiency in the harvesting of the stocks by disparate countries are made more difficult due to changes in the harvesting levels of one fleet affecting the rents of another fleet through changes in the age distribution of stock. These types of problem are under review by the Western and Central Pacific Fisheries Commission. Results from an age-structured steady-state bioeconomic model are used to show: the changes in fleet rents and catches of tuna if all fleets form a cooperative grand coalition to deploy fishing effort to maximize rents over the region; the likely non-stability of the grand coalition; and the inferior Nash Equilibria outcomes if fleets fish non-cooperatively to maximize their own rents. Close

• 18. [Article] Optimal Harvest in a Multispecies Age Structured Fishery Model at Different Level of Density Dependency

  Presentation

  Citation × Citation Citation Abstract Copy Title: Optimal Harvest in a Multispecies Age Structured Fishery Model at Different Level of Density Dependency Author: Poudel, Diwakar Presentation Title: Optimal Harvest in a Multispecies Age Structured Fishery Model at Different Level of Density Dependency Author: Poudel, Diwakar Presentation Close

• 19. [Article] Economics of Fish Harvesting in Nigeria: A Case Study of Yola North Local Government Area of Adamawa State

  Powerpoint Presentation and Research Paper

  Citation × Citation Citation Abstract Copy Title: Economics of Fish Harvesting in Nigeria: A Case Study of Yola North Local Government Area of Adamawa State Author: Adebayo, Elizabeth Powerpoint Presentation and Research Paper Title: Economics of Fish Harvesting in Nigeria: A Case Study of Yola North Local Government Area of Adamawa State Author: Adebayo, Elizabeth Powerpoint Presentation and Research Paper Close

• 20. [Article] Misplaced Concreteness: Prospects and Problems with Interdisciplinary Approaches to the Fisheries

  In an age of increasing complexity, simple answers no longer suffice, but the demand for greater sophistication is itself at odds with an era of growing specialization. Researchers must thus incorporate ...

  Citation × Citation Citation Abstract Copy Title: Misplaced Concreteness: Prospects and Problems with Interdisciplinary Approaches to the Fisheries Author: Tayloe, Joseph E. III Year: 2001 In an age of increasing complexity, simple answers no longer suffice, but the demand for greater sophistication is itself at odds with an era of growing specialization. Researchers must thus incorporate information from specialists in other fields. This trend in interdisciplinary research contains hidden challenges, however, including a necessary familiarity with the development, ideas, major questions, and dominant institutions of those disciplines. Title: Misplaced Concreteness: Prospects and Problems with Interdisciplinary Approaches to the Fisheries Author: Tayloe, Joseph E. III Year: 2001 In an age of increasing complexity, simple answers no longer suffice, but the demand for greater sophistication is itself at odds with an era of growing specialization. Researchers must thus incorporate information from specialists in other fields. This trend in interdisciplinary research contains hidden challenges, however, including a necessary familiarity with the development, ideas, major questions, and dominant institutions of those disciplines. Close

• 21. [Article] Optimal Effort Controls for the Multispecies Groundfish Complex in New England

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Optimal Effort Controls for the Multispecies Groundfish Complex in New England Author: Maguire, Jean-Jacques, Holland, Daniel S. Research Paper Title: Optimal Effort Controls for the Multispecies Groundfish Complex in New England Author: Maguire, Jean-Jacques, Holland, Daniel S. Research Paper Close

• 22. [Article] A Management Policy for North Japan Sea Sailfin Sandfish, Arctoscopus japonicus Stock

  Research Paper

  Citation × Citation Citation Abstract Copy Title: A Management Policy for North Japan Sea Sailfin Sandfish, Arctoscopus japonicus Stock Author: Sugishita, Shigeo, Sugiyama, Hideki, Suzuki, Naoki, Sakuramoto, Kazumi, Watanabe, Kyuji Research Paper Title: A Management Policy for North Japan Sea Sailfin Sandfish, Arctoscopus japonicus Stock Author: Sugishita, Shigeo, Sugiyama, Hideki, Suzuki, Naoki, Sakuramoto, Kazumi, Watanabe, Kyuji Research Paper Close

• 23. [Article] Influence of Climate Change and Natural Disasters for Fishing Communities and Propose Appropriate Policies

  No poster available.

  Citation × Citation Citation Abstract Copy Title: Influence of Climate Change and Natural Disasters for Fishing Communities and Propose Appropriate Policies Author: Quang, Khanh Van Tran, Nguyen, Linh No poster available. Title: Influence of Climate Change and Natural Disasters for Fishing Communities and Propose Appropriate Policies Author: Quang, Khanh Van Tran, Nguyen, Linh No poster available. Close

• 24. [Article] Measurement of Technical Efficiency of Farmed Catfish Production in Southwest, Nigeria: A Stochastic Frontier Production Function Approach

  Catfishes are the most popularly raised and consumed fish species in Nigeria. Given changes in the dynamics of the aquaculture sector, this paper estimated technical efficiency and factors contributing ...

  Citation × Citation Citation Abstract Copy Title: Measurement of Technical Efficiency of Farmed Catfish Production in Southwest, Nigeria: A Stochastic Frontier Production Function Approach Author: Mafimisebi, Taiwo Ejiola Catfishes are the most popularly raised and consumed fish species in Nigeria. Given changes in the dynamics of the aquaculture sector, this paper estimated technical efficiency and factors contributing to it using data collected from 108 farmers stocking catfish in earthen ponds in the study area. Catfish aquaculture was found to be capital intensive. The most expensive item of total variable cost (TVC) was fish feeds which accounted for 61.4% and 67.8% of TVC in Ondo and Ogun States, respectively. There were no significant differences in cost items between the two States. Empirical analysis showed wide variations in predicted TEs across farms ranging from 48.4% to 77.2% in Ondo State and 45.4% to 82.1% in Ogun State with means of 64.0% and 67.0%, respectively. The results also indicate that coefficients of the quantity of feeds, total number of ponds, labour and number of times pond water is changed were positive and highly significant in catfish production. The inefficiency model revealed that age and farming experience coefficients (significant) and education level coefficient (not significant) were negative indicating that older and more experienced farmers tended to be less inefficient. The test of various null hypotheses showed that the inefficiency effects were related to the age, management pattern, years of experience and education level of farmers. The study identified the opportunities that exist for improving TE in the study area. Results of the analysis having implications for the aquaculture industry and for policy-makers were discussed. Title: Measurement of Technical Efficiency of Farmed Catfish Production in Southwest, Nigeria: A Stochastic Frontier Production Function Approach Author: Mafimisebi, Taiwo Ejiola Catfishes are the most popularly raised and consumed fish species in Nigeria. Given changes in the dynamics of the aquaculture sector, this paper estimated technical efficiency and factors contributing to it using data collected from 108 farmers stocking catfish in earthen ponds in the study area. Catfish aquaculture was found to be capital intensive. The most expensive item of total variable cost (TVC) was fish feeds which accounted for 61.4% and 67.8% of TVC in Ondo and Ogun States, respectively. There were no significant differences in cost items between the two States. Empirical analysis showed wide variations in predicted TEs across farms ranging from 48.4% to 77.2% in Ondo State and 45.4% to 82.1% in Ogun State with means of 64.0% and 67.0%, respectively. The results also indicate that coefficients of the quantity of feeds, total number of ponds, labour and number of times pond water is changed were positive and highly significant in catfish production. The inefficiency model revealed that age and farming experience coefficients (significant) and education level coefficient (not significant) were negative indicating that older and more experienced farmers tended to be less inefficient. The test of various null hypotheses showed that the inefficiency effects were related to the age, management pattern, years of experience and education level of farmers. The study identified the opportunities that exist for improving TE in the study area. Results of the analysis having implications for the aquaculture industry and for policy-makers were discussed. Close

• 25. [Article] Precautionary Management of North-East Arctic Cod under Environmental and Evolutionary Change

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Precautionary Management of North-East Arctic Cod under Environmental and Evolutionary Change Author: Hjermann, Dag, Kaitala, Veijo Abstract only. Title: Precautionary Management of North-East Arctic Cod under Environmental and Evolutionary Change Author: Hjermann, Dag, Kaitala, Veijo Abstract only. Close

• 26. [Article] Health and Seafood Consumption Patterns among Women 45-69 years: A Norwegian Seafood Consumption Study 1996

  Submitted for publication in “Appetite” 26.04.01

  Citation × Citation Citation Abstract Copy Title: Health and Seafood Consumption Patterns among Women 45-69 years: A Norwegian Seafood Consumption Study 1996 Author: Lund, E., Trondsen, Torbjorn, Eggen, A.E., Braaten, T. Year: 2001 Submitted for publication in “Appetite” 26.04.01 Title: Health and Seafood Consumption Patterns among Women 45-69 years: A Norwegian Seafood Consumption Study 1996 Author: Lund, E., Trondsen, Torbjorn, Eggen, A.E., Braaten, T. Year: 2001 Submitted for publication in “Appetite” 26.04.01 Close

• 27. [Article] Age-Structure Metrics for Precautionary Management- Can we save fish, time, and money?

  Abstract Only

  Citation × Citation Citation Abstract Copy Title: Age-Structure Metrics for Precautionary Management- Can we save fish, time, and money? Author: Cusack, Christopher Abstract Only Title: Age-Structure Metrics for Precautionary Management- Can we save fish, time, and money? Author: Cusack, Christopher Abstract Only Close

• 28. [Article] Bioeconomic Modeling and Management of the Southern Bluefin Tuna Fishery

  The paper reviews the management and bioeconomic modeling of the Southern Bluefin Tuna stock. It describes two studies using simultaneous, non-cooperative, three player games to predict revenue and stock ...

  Citation × Citation Citation Abstract Copy Title: Bioeconomic Modeling and Management of the Southern Bluefin Tuna Fishery Author: Kennedy, John, Campbell, Harry The paper reviews the management and bioeconomic modeling of the Southern Bluefin Tuna stock. It describes two studies using simultaneous, non-cooperative, three player games to predict revenue and stock outcomes generated by a deterministic, discrete, age-structured model of the SBT population. Two versions of the model, corresponding to biological and harvesting conditions prevailing around 2000 and 2007 respectively are considered. Because of a significant downward revision of estimates of the productivity of the SBT stock between these two dates, the later model suggests that conservation and optimal utilization of the SBT stock will require a substantial cut in catch quotas as compared with the results of the earlier model. Title: Bioeconomic Modeling and Management of the Southern Bluefin Tuna Fishery Author: Kennedy, John, Campbell, Harry The paper reviews the management and bioeconomic modeling of the Southern Bluefin Tuna stock. It describes two studies using simultaneous, non-cooperative, three player games to predict revenue and stock outcomes generated by a deterministic, discrete, age-structured model of the SBT population. Two versions of the model, corresponding to biological and harvesting conditions prevailing around 2000 and 2007 respectively are considered. Because of a significant downward revision of estimates of the productivity of the SBT stock between these two dates, the later model suggests that conservation and optimal utilization of the SBT stock will require a substantial cut in catch quotas as compared with the results of the earlier model. Close

• 29. [Article] Sasi Laut as a Community-Based Fishery Resources Management in Maluku

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Sasi Laut as a Community-Based Fishery Resources Management in Maluku Author: Apituley, Yolanda Marla Tania Nangkah, Hiariey, J. Research Paper Title: Sasi Laut as a Community-Based Fishery Resources Management in Maluku Author: Apituley, Yolanda Marla Tania Nangkah, Hiariey, J. Research Paper Close

• 30. [Article] The Optimal Recovery of a Semelparous Fish Population with Delayed Recruitment

  Research Paper

  Citation × Citation Citation Abstract Copy Title: The Optimal Recovery of a Semelparous Fish Population with Delayed Recruitment Author: Alexander, Robert R., Doole, Graeme J. Research Paper Title: The Optimal Recovery of a Semelparous Fish Population with Delayed Recruitment Author: Alexander, Robert R., Doole, Graeme J. Research Paper Close

• 31. [Article] Optimization Model for the Oregon Ocean Shrimp Fishery

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Optimization Model for the Oregon Ocean Shrimp Fishery Author: Sylvia, Gilbert, Gallagher, Charmaine Marie Research Paper Title: Optimization Model for the Oregon Ocean Shrimp Fishery Author: Sylvia, Gilbert, Gallagher, Charmaine Marie Research Paper Close

• 32. [Article] Economic Performance of offshore Fisheries - the Case of Trawling and Purse Seining in Ben Tre Province, Vietnam

  Poster session.

  Citation × Citation Citation Abstract Copy Title: Economic Performance of offshore Fisheries - the Case of Trawling and Purse Seining in Ben Tre Province, Vietnam Author: Nguyen, Kim Anh Thi, Nguyen, Dien Van Poster session. Title: Economic Performance of offshore Fisheries - the Case of Trawling and Purse Seining in Ben Tre Province, Vietnam Author: Nguyen, Kim Anh Thi, Nguyen, Dien Van Poster session. Close

• 33. [Article] Lessons From the Collapse of the Stock of Anchovy in the Bay of Biscay

  No poster available.

  Citation × Citation Citation Abstract Copy Title: Lessons From the Collapse of the Stock of Anchovy in the Bay of Biscay Author: Del Valle Erkiaga, Ikerne, Astorkiza, Kepa No poster available. Title: Lessons From the Collapse of the Stock of Anchovy in the Bay of Biscay Author: Del Valle Erkiaga, Ikerne, Astorkiza, Kepa No poster available. Close

• 34. [Article] Age Structure Metrics for Precautionary Management: Can Simpler Assessment Techniques Save Fish, Time, and Money?

  Stock assessment techniques currently used in the United States are extremely costly to implement, involve significant data requirements, and are inaccessible to all but a few stock assessment scientists. ...

  Citation × Citation Citation Abstract Copy Title: Age Structure Metrics for Precautionary Management: Can Simpler Assessment Techniques Save Fish, Time, and Money? Author: Harte, Michael, Heppell, Selina, Sylvia, Gil, Cusack, Christopher, Larkin, Sherry Stock assessment techniques currently used in the United States are extremely costly to implement, involve significant data requirements, and are inaccessible to all but a few stock assessment scientists. A systematic decrease in fishery yields and the designation of several species as overfished on the west coast of the United States have resulted in stricter protocols regarding sustainable fisheries management and the rebuilding of overfished stocks, including the need to set annual harvest limits for all exploited species. An alternative and simpler approach to stock assessment which could address this need is described and an evaluation framework set up. Although no results have been obtained to date, possible costs and benefits of incorporating this approach into fisheries management are discussed. Title: Age Structure Metrics for Precautionary Management: Can Simpler Assessment Techniques Save Fish, Time, and Money? Author: Harte, Michael, Heppell, Selina, Sylvia, Gil, Cusack, Christopher, Larkin, Sherry Stock assessment techniques currently used in the United States are extremely costly to implement, involve significant data requirements, and are inaccessible to all but a few stock assessment scientists. A systematic decrease in fishery yields and the designation of several species as overfished on the west coast of the United States have resulted in stricter protocols regarding sustainable fisheries management and the rebuilding of overfished stocks, including the need to set annual harvest limits for all exploited species. An alternative and simpler approach to stock assessment which could address this need is described and an evaluation framework set up. Although no results have been obtained to date, possible costs and benefits of incorporating this approach into fisheries management are discussed. Close

• 35. [Article] An Analysis of the Tuna-Mackerel Gillnet Fishery in Nha Trang, Vietnam

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: An Analysis of the Tuna-Mackerel Gillnet Fishery in Nha Trang, Vietnam Author: Nguyen, Tuan, Flaaten, Ola, Nguyen, Kim Anh Thi, Nguyen, Tram Anh Thi Abstract only. Title: An Analysis of the Tuna-Mackerel Gillnet Fishery in Nha Trang, Vietnam Author: Nguyen, Tuan, Flaaten, Ola, Nguyen, Kim Anh Thi, Nguyen, Tram Anh Thi Abstract only. Close

• 36. [Article] North-East Arctic Cod Model

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: North-East Arctic Cod Model Author: Ekerhovd, Nils-Arne Abstract only. Title: North-East Arctic Cod Model Author: Ekerhovd, Nils-Arne Abstract only. Close

• 37. [Article] Consumer Demand for Meat, Poultry and Seafood in Taiwan

  This study provides estimates of a complete demand elasticities matrix for meat, poultry, fishery fish, aquaculture fish, as well as shrimp and shell fish in Taiwan, using the linear approximate almost ...

  Citation × Citation Citation Abstract Copy Title: Consumer Demand for Meat, Poultry and Seafood in Taiwan Author: Lee, Hwang-Jaw Year: 2001 This study provides estimates of a complete demand elasticities matrix for meat, poultry, fishery fish, aquaculture fish, as well as shrimp and shell fish in Taiwan, using the linear approximate almost ideal demand system. Estimation is based on aggregate annual consumption data complied from Taiwan Food Balance Sheets during 1970-1998. The estimated own-price elasticities indicate meat, poultry and seafood are all price inelastic. The results reveal that expenditure effects are strong for meat and fishery fish. The estimated cross-price elasticities are generally small and most products are gross complements. In addition, the effects of household size and the ratio of population aged over 64 on animal products consumption are observed to be significant. Moreover, own-price and expenditure elasticities computed at selected years reveal a possible change in pattern of consumption behavior which, however, may require further statistical analysis. Title: Consumer Demand for Meat, Poultry and Seafood in Taiwan Author: Lee, Hwang-Jaw Year: 2001 This study provides estimates of a complete demand elasticities matrix for meat, poultry, fishery fish, aquaculture fish, as well as shrimp and shell fish in Taiwan, using the linear approximate almost ideal demand system. Estimation is based on aggregate annual consumption data complied from Taiwan Food Balance Sheets during 1970-1998. The estimated own-price elasticities indicate meat, poultry and seafood are all price inelastic. The results reveal that expenditure effects are strong for meat and fishery fish. The estimated cross-price elasticities are generally small and most products are gross complements. In addition, the effects of household size and the ratio of population aged over 64 on animal products consumption are observed to be significant. Moreover, own-price and expenditure elasticities computed at selected years reveal a possible change in pattern of consumption behavior which, however, may require further statistical analysis. Close

• 38. [Article] Sea Turtles of Bahia Magdalena, Baja California Sur, Mexico: Demand and Supply of an Endangered Species

  Sea turtles have historically been a primary resource for many of the coastal inhabitants of Bahia Magdalena, Baja California Sur, Mexico. Despite their endangered status and the implementation in 1990 ...

  Citation × Citation Citation Abstract Copy Title: Sea Turtles of Bahia Magdalena, Baja California Sur, Mexico: Demand and Supply of an Endangered Species Author: Garcia-Martinez, S., Nichols, W.J. Year: 2001 Sea turtles have historically been a primary resource for many of the coastal inhabitants of Bahia Magdalena, Baja California Sur, Mexico. Despite their endangered status and the implementation in 1990 of Mexican laws prohibiting the harvest of sea turtles, the demand for and the supply of these animals has persisted to some degree. To determine the current demand for sea turtles 122 surveys and 56 interviews were conducted (June 12th-30th, 1999) throughout the Bahia Magdalena region. Through a generalized least squares (GLS) analysis it was estimated that 35.7% of the variation in demand was explained by six independent variables. The GLS model shows that the family size, special occasions of consumption such as birthdays, and the decline in sea turtle populations positively affect the demand function. The person's occupation, monthly income, and the 1990 ban on sea turtle harvest negatively affect this demand. Ninety-four surveys and seventy interviews conducted in the region (July 24th-August 1st, 1999) were used to describe a supply function. The GLS estimation indicates that 27.8% of the variation in the supply of sea turtles in the bay is influenced by nine variables. Age, level of education, fishing practices, number of dependents, availability of sea turtles, and culture significantly affect the supply of sea turtles in the Bahia Magdalena region. Title: Sea Turtles of Bahia Magdalena, Baja California Sur, Mexico: Demand and Supply of an Endangered Species Author: Garcia-Martinez, S., Nichols, W.J. Year: 2001 Sea turtles have historically been a primary resource for many of the coastal inhabitants of Bahia Magdalena, Baja California Sur, Mexico. Despite their endangered status and the implementation in 1990 of Mexican laws prohibiting the harvest of sea turtles, the demand for and the supply of these animals has persisted to some degree. To determine the current demand for sea turtles 122 surveys and 56 interviews were conducted (June 12th-30th, 1999) throughout the Bahia Magdalena region. Through a generalized least squares (GLS) analysis it was estimated that 35.7% of the variation in demand was explained by six independent variables. The GLS model shows that the family size, special occasions of consumption such as birthdays, and the decline in sea turtle populations positively affect the demand function. The person's occupation, monthly income, and the 1990 ban on sea turtle harvest negatively affect this demand. Ninety-four surveys and seventy interviews conducted in the region (July 24th-August 1st, 1999) were used to describe a supply function. The GLS estimation indicates that 27.8% of the variation in the supply of sea turtles in the bay is influenced by nine variables. Age, level of education, fishing practices, number of dependents, availability of sea turtles, and culture significantly affect the supply of sea turtles in the Bahia Magdalena region. Close

• 39. [Article] International Management Strategies for a Migratory Fish Stock: A Bio-economic Simulation Model of the Norwegian Spring-spawning Herring Fishery

  In this paper, a three-country dynamic bio-economic model is presented and used to simulate catch levels, stock size and profit potential of alternative management strategies for the Norwegian spring-spawning ...

  Citation × Citation Citation Abstract Copy Title: International Management Strategies for a Migratory Fish Stock: A Bio-economic Simulation Model of the Norwegian Spring-spawning Herring Fishery Author: Gordon, Daniel V., Bjorndal, Trond, Lindroos, Marko, Kaitala, Veijo Year: 2001 In this paper, a three-country dynamic bio-economic model is presented and used to simulate catch levels, stock size and profit potential of alternative management strategies for the Norwegian spring-spawning herring fishery. Management of the herring fishery is complicated by the migratory behaviour of the species moving between coastal state zones and the high seas. The biological model is described by a discrete time age structured model and the economic model is described by a rent maximising model with constant price of herring and different costs of harvesting and efficiency levels for the different national fleets. The simulations are carried out over a 70-year period and show that the benefits of international cooperation far exceed the returns of a competitive open access fishery. Title: International Management Strategies for a Migratory Fish Stock: A Bio-economic Simulation Model of the Norwegian Spring-spawning Herring Fishery Author: Gordon, Daniel V., Bjorndal, Trond, Lindroos, Marko, Kaitala, Veijo Year: 2001 In this paper, a three-country dynamic bio-economic model is presented and used to simulate catch levels, stock size and profit potential of alternative management strategies for the Norwegian spring-spawning herring fishery. Management of the herring fishery is complicated by the migratory behaviour of the species moving between coastal state zones and the high seas. The biological model is described by a discrete time age structured model and the economic model is described by a rent maximising model with constant price of herring and different costs of harvesting and efficiency levels for the different national fleets. The simulations are carried out over a 70-year period and show that the benefits of international cooperation far exceed the returns of a competitive open access fishery. Close

• 40. [Article] The Development of a Bioeconomic Model for the Oregon Ocean Shrimp Fishery

  Selecting ‘optimal’ strategies to manage Oregon ocean shrimp is challenged by uncertain and variable natural mortality, recruitment, and growth. Fishery management is focused on measures to prevent long-term ...

  Citation × Citation Citation Abstract Copy Title: The Development of a Bioeconomic Model for the Oregon Ocean Shrimp Fishery Author: Sylvia, Gilbert, Hannah, Robert, Gallagher, Charmaine Marie Year: 2001 Selecting ‘optimal’ strategies to manage Oregon ocean shrimp is challenged by uncertain and variable natural mortality, recruitment, and growth. Fishery management is focused on measures to prevent long-term biological damage to the stock, to protect age-1 shrimp from overharvest and to sustain long term fishery benefits. Developing harvest strategies such as mesh size and season dates are complicated by economic factors including differences in output prices as a function of shrimp size. To address these questions economic information was integrated with biological data to develop static and dynamic bioeconomic models. Equilibrium biological yield per recruit and revenue per recruit models indicate that a delay in the season opening of this fishery would generate increased revenue as a result of shrimp growth and size-based price differentials. Results using a dynamic non-linear programming model indicate targeting fishing intensity later in the season can generate better yield and revenue. Sensitivity analysis indicates that higher rates of natural mortality will decrease the benefits of delaying the season opening. Future research will build on this analysis by including selectivity at length, variable recruitment, harvester and processor costs, and product quality. Title: The Development of a Bioeconomic Model for the Oregon Ocean Shrimp Fishery Author: Sylvia, Gilbert, Hannah, Robert, Gallagher, Charmaine Marie Year: 2001 Selecting ‘optimal’ strategies to manage Oregon ocean shrimp is challenged by uncertain and variable natural mortality, recruitment, and growth. Fishery management is focused on measures to prevent long-term biological damage to the stock, to protect age-1 shrimp from overharvest and to sustain long term fishery benefits. Developing harvest strategies such as mesh size and season dates are complicated by economic factors including differences in output prices as a function of shrimp size. To address these questions economic information was integrated with biological data to develop static and dynamic bioeconomic models. Equilibrium biological yield per recruit and revenue per recruit models indicate that a delay in the season opening of this fishery would generate increased revenue as a result of shrimp growth and size-based price differentials. Results using a dynamic non-linear programming model indicate targeting fishing intensity later in the season can generate better yield and revenue. Sensitivity analysis indicates that higher rates of natural mortality will decrease the benefits of delaying the season opening. Future research will build on this analysis by including selectivity at length, variable recruitment, harvester and processor costs, and product quality. Close

• 41. [Article] Several Major Factors Influencing Revenues of the Yellowfin Tuna Long-lining Fishery in Phu Yen Province

  Vietnam is in the club of countries gifted with the long coastal line, and strong in marine features accordingly. Fishing operations are artisan characteristic and the management method is primarily open ...

  Citation × Citation Citation Abstract Copy Title: Several Major Factors Influencing Revenues of the Yellowfin Tuna Long-lining Fishery in Phu Yen Province Author: Phan, Thi Dung Vietnam is in the club of countries gifted with the long coastal line, and strong in marine features accordingly. Fishing operations are artisan characteristic and the management method is primarily open – access. Since the past few years, the yellow fin tuna long- lining fishery has become one sub-sector experiencing high growth rate in the region of South Centre of Vietnam. Phu Yen Province has been a special case in point. Fishers there have invested much capital into developing these ventures that culminates in the sharp increase of vessel numbers, total catch and therefore revenue. This paper is to look into some factors namely engine power (capacity), fishers, production organizations, equipment values, vessel age, baits, education level of skippers, which together impact revenues of the long-lining fishery in Phu Yen Province. Results of the model under examination are statistically significant. Generally, the research findings are consistent to those previously inferred in international papers. Based on this research, some orientations for management have been suggested. Title: Several Major Factors Influencing Revenues of the Yellowfin Tuna Long-lining Fishery in Phu Yen Province Author: Phan, Thi Dung Vietnam is in the club of countries gifted with the long coastal line, and strong in marine features accordingly. Fishing operations are artisan characteristic and the management method is primarily open – access. Since the past few years, the yellow fin tuna long- lining fishery has become one sub-sector experiencing high growth rate in the region of South Centre of Vietnam. Phu Yen Province has been a special case in point. Fishers there have invested much capital into developing these ventures that culminates in the sharp increase of vessel numbers, total catch and therefore revenue. This paper is to look into some factors namely engine power (capacity), fishers, production organizations, equipment values, vessel age, baits, education level of skippers, which together impact revenues of the long-lining fishery in Phu Yen Province. Results of the model under examination are statistically significant. Generally, the research findings are consistent to those previously inferred in international papers. Based on this research, some orientations for management have been suggested. Close

• 42. [Article] Implications of bycatch reduction strategies for the economic viability of mixed fisheries

  There is growing recognition worldwide that the impacts of fishing on non-targeted components of marine ecosystems should be included in the assessment of fisheries sustainability. This leads to the inclusion ...

  Citation × Citation Citation Abstract Copy Title: Implications of bycatch reduction strategies for the economic viability of mixed fisheries Author: Thebaud, Olivier, Martinet, Vincent There is growing recognition worldwide that the impacts of fishing on non-targeted components of marine ecosystems should be included in the assessment of fisheries sustainability. This leads to the inclusion of new constraints in evaluations of the long-term bio-economic performance of fisheries. In this paper, we analyze the implications of such constraints based on the case of bycatch of juvenile hake in the Bay of Biscay (ICES area VIIIa,b) trawl fishery for nephrops. The analysis is based on a discrete time model of the trawl fishery including an age-structured representation of stock dynamics, with uncertainty. We define sustainability using the viability framework of analysis: viability objectives are represented as constraints which relate to the economic status of the fishing fleet and to the biological status of fish stocks. We include an ecological constraint defined as a minimal target threshold for the recruitment of mature hakes, which is related to the fishing mortality induced by trawlers on juvenile hake. Based on stochastic analysis, we define the probability that both economic and ecosystemic constraints are met, as a function of the level of these constraints. We use the model to assess the sustainability of the fishery under different scenarios as regards bycatch reduction strategies. Title: Implications of bycatch reduction strategies for the economic viability of mixed fisheries Author: Thebaud, Olivier, Martinet, Vincent There is growing recognition worldwide that the impacts of fishing on non-targeted components of marine ecosystems should be included in the assessment of fisheries sustainability. This leads to the inclusion of new constraints in evaluations of the long-term bio-economic performance of fisheries. In this paper, we analyze the implications of such constraints based on the case of bycatch of juvenile hake in the Bay of Biscay (ICES area VIIIa,b) trawl fishery for nephrops. The analysis is based on a discrete time model of the trawl fishery including an age-structured representation of stock dynamics, with uncertainty. We define sustainability using the viability framework of analysis: viability objectives are represented as constraints which relate to the economic status of the fishing fleet and to the biological status of fish stocks. We include an ecological constraint defined as a minimal target threshold for the recruitment of mature hakes, which is related to the fishing mortality induced by trawlers on juvenile hake. Based on stochastic analysis, we define the probability that both economic and ecosystemic constraints are met, as a function of the level of these constraints. We use the model to assess the sustainability of the fishery under different scenarios as regards bycatch reduction strategies. Close

• 43. [Article] Consumer Concern for Ethical Issues in Fish Farming: A Segmentation Study

  The main objective of this paper was to study consumer concern for ethical and environmental issues regarding fishing and aquaculture. Cross-sectional data was collected in Valencia, Spain. A total sample ...

  Citation × Citation Citation Abstract Copy Title: Consumer Concern for Ethical Issues in Fish Farming: A Segmentation Study Author: Olsen, Svein Ottar, Honkanen, Pirjo The main objective of this paper was to study consumer concern for ethical and environmental issues regarding fishing and aquaculture. Cross-sectional data was collected in Valencia, Spain. A total sample of 452 consumers was obtained. This study uses descriptive and multivariate techniques to present data, and to obtain and describe the segments. The analysis resulted in three segments: the unconcerned, the wild fish concerned and the ambivalent. These represented 27%, 35% and 39% of the sample respectively. The segments were profiled with variables age, gender, education, social class, fish consumption, attitudes towards fish, attitudes towards farmed fish, perceived knowledge about fish farming, health involvement and the type of information used when buying fish (product vs. environmental). Title: Consumer Concern for Ethical Issues in Fish Farming: A Segmentation Study Author: Olsen, Svein Ottar, Honkanen, Pirjo The main objective of this paper was to study consumer concern for ethical and environmental issues regarding fishing and aquaculture. Cross-sectional data was collected in Valencia, Spain. A total sample of 452 consumers was obtained. This study uses descriptive and multivariate techniques to present data, and to obtain and describe the segments. The analysis resulted in three segments: the unconcerned, the wild fish concerned and the ambivalent. These represented 27%, 35% and 39% of the sample respectively. The segments were profiled with variables age, gender, education, social class, fish consumption, attitudes towards fish, attitudes towards farmed fish, perceived knowledge about fish farming, health involvement and the type of information used when buying fish (product vs. environmental). Close

• 44. [Article] Factors Affecting the Decision Process of Catfish Consumers: An Empirical Study in the Two Biggest Cities in Vietnam

  The consumption of catfish in Vietnam has not grown enough to match their increased production. The objective of this study is to explore the factors that influence the decision process of catfish consumers ...

  Citation × Citation Citation Abstract Copy Title: Factors Affecting the Decision Process of Catfish Consumers: An Empirical Study in the Two Biggest Cities in Vietnam Author: Myrland, Oystein, Huynh, Mai Thi Xuan The consumption of catfish in Vietnam has not grown enough to match their increased production. The objective of this study is to explore the factors that influence the decision process of catfish consumers in Vietnam. The findings provide information for the Vietnamese catfish industry to better attract more domestic consumers to eat catfish. This study seeks to address its objective by examining the relationships that exist between the experiences, perceptions of product attributes, preference, market constraints, and consumption levels of consumers for catfish products. Data collected in the two biggest cities in Vietnam is analyzed by using multivariate techniques based on a partially-recursive model. Factors such as age, region, ease of preparation, perceptions of catfish taste, odour, and fat along with beliefs that catfish are safe and inexpensive are found to significantly influence the decision-making process. Title: Factors Affecting the Decision Process of Catfish Consumers: An Empirical Study in the Two Biggest Cities in Vietnam Author: Myrland, Oystein, Huynh, Mai Thi Xuan The consumption of catfish in Vietnam has not grown enough to match their increased production. The objective of this study is to explore the factors that influence the decision process of catfish consumers in Vietnam. The findings provide information for the Vietnamese catfish industry to better attract more domestic consumers to eat catfish. This study seeks to address its objective by examining the relationships that exist between the experiences, perceptions of product attributes, preference, market constraints, and consumption levels of consumers for catfish products. Data collected in the two biggest cities in Vietnam is analyzed by using multivariate techniques based on a partially-recursive model. Factors such as age, region, ease of preparation, perceptions of catfish taste, odour, and fat along with beliefs that catfish are safe and inexpensive are found to significantly influence the decision-making process. Close

• 45. [Article] Analysis of the French demand for oysters and mussels, within the European market

  Shellfish farming is the most common and the most established activity of aquaculture in France and in EU15. Such as main suppliers of mussels and oysters, mariculture production makes up the referent ...

  Citation × Citation Citation Abstract Copy Title: Analysis of the French demand for oysters and mussels, within the European market Author: Mariojouls, Catherine, Girard, Sophie Year: 2001 Shellfish farming is the most common and the most established activity of aquaculture in France and in EU15. Such as main suppliers of mussels and oysters, mariculture production makes up the referent market for bivalves molluscs, unlike most other aquatic species for which capture fisheries are prevalent. Moreover, the specificity of oyster cultivation is marked with respect to the French position which is both leader and almost self sufficient on the European market. The sustainable development of shellfish farming is analysed through a demand-oriented-approach . The field of the study covers trading and marketing issues as well as consumer analysis. The comparison between the mussel and the oyster market highlight some key differences, in terms of distribution network, identification of origin and products differentiation, consumer profiles and regions. This lead to examine deeply the ways of market segmentation in relation with the image of the product and the consumer expectations. Quantitative surveys, mainly consumer panels, are used over a 15 years period to attempt a dynamic approach of the age criteria (consumers life cycle and generation effect). This is completed by a qualitative analysis of consumer attitude towards shellfish and an overview of the current innovation process in the two sectors concerned. Title: Analysis of the French demand for oysters and mussels, within the European market Author: Mariojouls, Catherine, Girard, Sophie Year: 2001 Shellfish farming is the most common and the most established activity of aquaculture in France and in EU15. Such as main suppliers of mussels and oysters, mariculture production makes up the referent market for bivalves molluscs, unlike most other aquatic species for which capture fisheries are prevalent. Moreover, the specificity of oyster cultivation is marked with respect to the French position which is both leader and almost self sufficient on the European market. The sustainable development of shellfish farming is analysed through a demand-oriented-approach . The field of the study covers trading and marketing issues as well as consumer analysis. The comparison between the mussel and the oyster market highlight some key differences, in terms of distribution network, identification of origin and products differentiation, consumer profiles and regions. This lead to examine deeply the ways of market segmentation in relation with the image of the product and the consumer expectations. Quantitative surveys, mainly consumer panels, are used over a 15 years period to attempt a dynamic approach of the age criteria (consumers life cycle and generation effect). This is completed by a qualitative analysis of consumer attitude towards shellfish and an overview of the current innovation process in the two sectors concerned. Close

• 46. [Article] The “Fast Fish” Campaign in Japan and Consumers’ Consciousness of Marine Environmental Preservation

  Extended Abstract and Presentation

  Citation × Citation Citation Abstract Copy Title: The “Fast Fish” Campaign in Japan and Consumers’ Consciousness of Marine Environmental Preservation Author: Mochizuki, M., Tatefuku, I., Oishi, Taro Extended Abstract and Presentation Title: The “Fast Fish” Campaign in Japan and Consumers’ Consciousness of Marine Environmental Preservation Author: Mochizuki, M., Tatefuku, I., Oishi, Taro Extended Abstract and Presentation Close

• 47. [Article] The Promise of Transferable Fishing Concessions

  Presentation

  Citation × Citation Citation Abstract Copy Title: The Promise of Transferable Fishing Concessions Author: Kucuksenel, Serkan, Kanik, Zafer Presentation Title: The Promise of Transferable Fishing Concessions Author: Kucuksenel, Serkan, Kanik, Zafer Presentation Close

• 48. [Article] Modeling Heterogeneous Fishing Fleet in an Ecosystem Based Management Context

  Multispecies fisheries pose a considerable management difficulty with respect to quota allocation between species. Externalities of direct control over the harvest may include, among others, creation of ...

  Citation × Citation Citation Abstract Copy Title: Modeling Heterogeneous Fishing Fleet in an Ecosystem Based Management Context Author: Hutniczak, Barbara Multispecies fisheries pose a considerable management difficulty with respect to quota allocation between species. Externalities of direct control over the harvest may include, among others, creation of unbalanced predator‐prey relationships in the environment. That, in turn, may affect the individual economic incentives of fishing vessels. Combining economic and ecological factors in one model has multiple advantages, whereas there have been little attempts to coordinate setting the total allowable catches in multispecies fisheries, particularly in the context of individual decision‐making process. The objective of this article is to develop a methodological framework for multispecies modeling with integrated ecological and economic realism suitable to evaluate the long term implications of the imposed regulations that can be used for better policy guidance. An empirical application is provided for the central Baltic Sea with its interacting fish community dominated by three species: cod, herring and sprat. The developed model includes three separate, dynamically updating, age‐structured submodels for each species, which are linked through predation. The harvest component is associated with the fishing vessels that optimize individual behavior subject to regulations, owned capital and individual technical efficiency derived with the use of a multiproduct distance function. The findings present a clear picture of asymmetries between vessels with respect to harvest process and reveal the rational harvest strategy that is accommodated in the multispecies simulation model. Title: Modeling Heterogeneous Fishing Fleet in an Ecosystem Based Management Context Author: Hutniczak, Barbara Multispecies fisheries pose a considerable management difficulty with respect to quota allocation between species. Externalities of direct control over the harvest may include, among others, creation of unbalanced predator‐prey relationships in the environment. That, in turn, may affect the individual economic incentives of fishing vessels. Combining economic and ecological factors in one model has multiple advantages, whereas there have been little attempts to coordinate setting the total allowable catches in multispecies fisheries, particularly in the context of individual decision‐making process. The objective of this article is to develop a methodological framework for multispecies modeling with integrated ecological and economic realism suitable to evaluate the long term implications of the imposed regulations that can be used for better policy guidance. An empirical application is provided for the central Baltic Sea with its interacting fish community dominated by three species: cod, herring and sprat. The developed model includes three separate, dynamically updating, age‐structured submodels for each species, which are linked through predation. The harvest component is associated with the fishing vessels that optimize individual behavior subject to regulations, owned capital and individual technical efficiency derived with the use of a multiproduct distance function. The findings present a clear picture of asymmetries between vessels with respect to harvest process and reveal the rational harvest strategy that is accommodated in the multispecies simulation model. Close

• 49. [Article] DATA MINING MULTIPLE STAKEHOLDERS’ RESPONSES TO DECLINING SCHIZOTHORAX FISHERY IN THE LAKES OF KASHMIR, INDIA

  Research paper and presentation

  Citation × Citation Citation Abstract Copy Title: DATA MINING MULTIPLE STAKEHOLDERS’ RESPONSES TO DECLINING SCHIZOTHORAX FISHERY IN THE LAKES OF KASHMIR, INDIA Author: Melake Araya, Tesfom, Sundaramoorthy, C., Quereshi, Neha W., Ramasubramanian, V., Krishnan, M. Research paper and presentation Title: DATA MINING MULTIPLE STAKEHOLDERS’ RESPONSES TO DECLINING SCHIZOTHORAX FISHERY IN THE LAKES OF KASHMIR, INDIA Author: Melake Araya, Tesfom, Sundaramoorthy, C., Quereshi, Neha W., Ramasubramanian, V., Krishnan, M. Research paper and presentation Close

• 50. [Article] THE INFLUENCE OF ECONOMIC GLOBALIZATION TO SEAFOOD CONSUMPTION DEMAND OF CHINESE RESIDENTS

  Research paper and presentation

  Citation × Citation Citation Abstract Copy Title: THE INFLUENCE OF ECONOMIC GLOBALIZATION TO SEAFOOD CONSUMPTION DEMAND OF CHINESE RESIDENTS Author: Chen, Sun Research paper and presentation Title: THE INFLUENCE OF ECONOMIC GLOBALIZATION TO SEAFOOD CONSUMPTION DEMAND OF CHINESE RESIDENTS Author: Chen, Sun Research paper and presentation Close