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• 1. [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

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

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  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

• 3. [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

• 4. [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

• 5. [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

• 6. [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

• 7. [Article] A Spatial Bioeconomic Model of West Indian Ocean Tuna Fisheries. Assessing Mpas Relevance for Highly Migratory Species

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: A Spatial Bioeconomic Model of West Indian Ocean Tuna Fisheries. Assessing Mpas Relevance for Highly Migratory Species Author: Fortilus, Jeanne, Chaboud, Christian Abstract only. Title: A Spatial Bioeconomic Model of West Indian Ocean Tuna Fisheries. Assessing Mpas Relevance for Highly Migratory Species Author: Fortilus, Jeanne, Chaboud, Christian Abstract only. Close

• 8. [Article] A Vessel Cost Sampling Model

  The Social Sciences Branch (SSB) of NOAA’s Northeast Fisheries Science Center (NEFSC) uses economic data to estimate the economic impacts of fisheries regulatory actions. Since 1995, the Northeast Fisheries ...

  Citation × Citation Citation Abstract Copy Title: A Vessel Cost Sampling Model Author: Gates, John M., Kitts, Andrew The Social Sciences Branch (SSB) of NOAA’s Northeast Fisheries Science Center (NEFSC) uses economic data to estimate the economic impacts of fisheries regulatory actions. Since 1995, the Northeast Fisheries Observer Program has collected trip cost information from commercial fishing vessels on which observers have been deployed. However, the allocation of observer coverage to fisheries is largely determined by non-economic needs (e.g., regulatory compliance and monitoring, bycatch estimation, and assessment of protected species interactions). To obtain cost data from a much wide variety of fisheries, the SSB funds additional observer coverage to acquire economic data from underrepresented fisheries. In this paper, we describe a mathematical programming model to allocate marginal observer coverage, in terms of observer sea days. We apply a simple logarithmic utility function to the fisheries of New England. The potential universe of observations is divided into strata based on vessel size, gear type, and state of landing. Certain a priori assumptions underlie the approach: • Costs are assumed heterogeneous across strata until such time as statistical analysis supports the null hypothesis • The marginal utility of observations in a given cell is subject to diminishing returns • The utility of observations decays with age • The marginal utility of zero observations is positive and finite • The cost-effectiveness of data collection can be reduced by software that automates the process In addition: • Data collection each year is limited by a budget • Current data collection takes into account the amount of past data for each cell and most data will be collected via other programs Title: A Vessel Cost Sampling Model Author: Gates, John M., Kitts, Andrew The Social Sciences Branch (SSB) of NOAA’s Northeast Fisheries Science Center (NEFSC) uses economic data to estimate the economic impacts of fisheries regulatory actions. Since 1995, the Northeast Fisheries Observer Program has collected trip cost information from commercial fishing vessels on which observers have been deployed. However, the allocation of observer coverage to fisheries is largely determined by non-economic needs (e.g., regulatory compliance and monitoring, bycatch estimation, and assessment of protected species interactions). To obtain cost data from a much wide variety of fisheries, the SSB funds additional observer coverage to acquire economic data from underrepresented fisheries. In this paper, we describe a mathematical programming model to allocate marginal observer coverage, in terms of observer sea days. We apply a simple logarithmic utility function to the fisheries of New England. The potential universe of observations is divided into strata based on vessel size, gear type, and state of landing. Certain a priori assumptions underlie the approach: • Costs are assumed heterogeneous across strata until such time as statistical analysis supports the null hypothesis • The marginal utility of observations in a given cell is subject to diminishing returns • The utility of observations decays with age • The marginal utility of zero observations is positive and finite • The cost-effectiveness of data collection can be reduced by software that automates the process In addition: • Data collection each year is limited by a budget • Current data collection takes into account the amount of past data for each cell and most data will be collected via other programs Close

• 9. [Article] Spatial management of small-scale fisheries targeting metapopulations with source-sink configuration: a parsimonious ecosystem approach

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  Citation × Citation Citation Abstract Copy Title: Spatial management of small-scale fisheries targeting metapopulations with source-sink configuration: a parsimonious ecosystem approach Author: Seijo, Juan Carlos Abstract only. Title: Spatial management of small-scale fisheries targeting metapopulations with source-sink configuration: a parsimonious ecosystem approach Author: Seijo, Juan Carlos Abstract only. Close

• 10. [Article] Linking ecology, economics, and fleet dynamics to evaluate alternative management strategies for US West Coast trawl fisheries

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  Citation × Citation Citation Abstract Copy Title: Linking ecology, economics, and fleet dynamics to evaluate alternative management strategies for US West Coast trawl fisheries Author: Kaplan, Isaac, Fulton, Elizabeth, Holland, Daniel Abstract only. Title: Linking ecology, economics, and fleet dynamics to evaluate alternative management strategies for US West Coast trawl fisheries Author: Kaplan, Isaac, Fulton, Elizabeth, Holland, Daniel Abstract only. Close