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• 1. [Article] A Double Hurdle Application of Fishermen’s Catch Sales Through Fish Mothers in Ghana

  Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), ...

  Citation × Citation Citation Abstract Copy Title: A Double Hurdle Application of Fishermen’s Catch Sales Through Fish Mothers in Ghana Author: Quagrainie, Kwamena, Chu, Jingjie Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Title: A Double Hurdle Application of Fishermen’s Catch Sales Through Fish Mothers in Ghana Author: Quagrainie, Kwamena, Chu, Jingjie Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Close

• 2. [Article] Confidence of the Trembling Hand: Bayseian Learning with Data Poor Stocks

  Management of data-poor fisheries typically relies on setting an annual catch limit (ACL) using catch-based methods that are concerned with estimating a sustainable harvest and hinge on the logic that ...

  Citation × Citation Citation Abstract Copy Title: Confidence of the Trembling Hand: Bayseian Learning with Data Poor Stocks Author: Qu, Qian, Holzer, Jorge Management of data-poor fisheries typically relies on setting an annual catch limit (ACL) using catch-based methods that are concerned with estimating a sustainable harvest and hinge on the logic that historic catches reflect a level of exploitation the stock can sustain. The resulting harvest control rules routinely set ACLs at the median (or mean) landings over a reference period, with or without a scalar downward adjustment according to the assumed level of depletion. Thus, the only way for the ACL to increase in the future is for the fishery to routinely exceed the ACL, which may be highly unlikely with strong enforcement. We propose an alternative approach: perturbations in the form of small, temporary and intermittent increases to ACLs between stock assessments (combined with a safety valve) can increase the permanent value of the stock. On one hand, these perturbations translate into a more accurate estimation of the population model in the next assessment, which leads to ACLs closer to the true maximum sustainable yield thereafter. On the other hand, increases in ACLs imply a higher management risk in the form of overfishing. To characterize this tradeoff, we first build a dynamic stochastic model that summarizes the interaction among the stock, the industry and the regulator. Then we perform several Monte Carlo experiments. We find that under reasonable parameterization, a wide range of perturbations give rise to a net present value of the stock that not only in expectation is higher than, but oftentimes first-order stochastically dominates that without perturbation. Title: Confidence of the Trembling Hand: Bayseian Learning with Data Poor Stocks Author: Qu, Qian, Holzer, Jorge Management of data-poor fisheries typically relies on setting an annual catch limit (ACL) using catch-based methods that are concerned with estimating a sustainable harvest and hinge on the logic that historic catches reflect a level of exploitation the stock can sustain. The resulting harvest control rules routinely set ACLs at the median (or mean) landings over a reference period, with or without a scalar downward adjustment according to the assumed level of depletion. Thus, the only way for the ACL to increase in the future is for the fishery to routinely exceed the ACL, which may be highly unlikely with strong enforcement. We propose an alternative approach: perturbations in the form of small, temporary and intermittent increases to ACLs between stock assessments (combined with a safety valve) can increase the permanent value of the stock. On one hand, these perturbations translate into a more accurate estimation of the population model in the next assessment, which leads to ACLs closer to the true maximum sustainable yield thereafter. On the other hand, increases in ACLs imply a higher management risk in the form of overfishing. To characterize this tradeoff, we first build a dynamic stochastic model that summarizes the interaction among the stock, the industry and the regulator. Then we perform several Monte Carlo experiments. We find that under reasonable parameterization, a wide range of perturbations give rise to a net present value of the stock that not only in expectation is higher than, but oftentimes first-order stochastically dominates that without perturbation. Close

• 3. [Article] A Qualitative Risk Assessment of Hookah Diving as Fishing Technology in Small-Scale Fisheries

  In many small-scale fisheries around the world, hookah diving is the main fishing method and gear to catch high-value species like sea urchin, sea cucumber, queen conch and spiny lobster. Decompression ...

  Citation × Citation Citation Abstract Copy Title: A Qualitative Risk Assessment of Hookah Diving as Fishing Technology in Small-Scale Fisheries Author: Seijo, Juan Carlos, Huchim, Oswaldo In many small-scale fisheries around the world, hookah diving is the main fishing method and gear to catch high-value species like sea urchin, sea cucumber, queen conch and spiny lobster. Decompression sickness (DCS) and carbon monoxide poisoning (COP) are diseases related to hookah diving and are the cause of non-fatal and fatal injuries in small-scale fishers with the social and economic effects over households and coastal communities. A misunderstanding about diving risks still prevails among small-scale fishers. This study reports on a qualitative risk analysis method developed to obtain fishers perception, the likelihood of undesired health threatening events occurring as a result of hookah diving, and the corresponding perceptions of impacts or consequences of such accidents. These risk perceptions are contrasted with hyperbaric physicians’ perceptions and the actual diving accidents occurring in the spiny lobster (P. argus) and sea cucumber (I. badionotus) small-scale fisheries in a Yucatan northeastern coastal community. Fishers identified the DCS as a major problem in the diving activity; however, their impact value perceived was lower than the one perceived by the physicians. Fishers diving behavior exceeded the recommended standards for a safety diving practice. The method allows for identification of priority decisions relevant to the need for appropriate fishing technologies, for fishers capacity building associated with health-related precautionary measures, and increased community awareness of possible consequences of current fishing technology.  Title: A Qualitative Risk Assessment of Hookah Diving as Fishing Technology in Small-Scale Fisheries Author: Seijo, Juan Carlos, Huchim, Oswaldo In many small-scale fisheries around the world, hookah diving is the main fishing method and gear to catch high-value species like sea urchin, sea cucumber, queen conch and spiny lobster. Decompression sickness (DCS) and carbon monoxide poisoning (COP) are diseases related to hookah diving and are the cause of non-fatal and fatal injuries in small-scale fishers with the social and economic effects over households and coastal communities. A misunderstanding about diving risks still prevails among small-scale fishers. This study reports on a qualitative risk analysis method developed to obtain fishers perception, the likelihood of undesired health threatening events occurring as a result of hookah diving, and the corresponding perceptions of impacts or consequences of such accidents. These risk perceptions are contrasted with hyperbaric physicians’ perceptions and the actual diving accidents occurring in the spiny lobster (P. argus) and sea cucumber (I. badionotus) small-scale fisheries in a Yucatan northeastern coastal community. Fishers identified the DCS as a major problem in the diving activity; however, their impact value perceived was lower than the one perceived by the physicians. Fishers diving behavior exceeded the recommended standards for a safety diving practice. The method allows for identification of priority decisions relevant to the need for appropriate fishing technologies, for fishers capacity building associated with health-related precautionary measures, and increased community awareness of possible consequences of current fishing technology.  Close

• 4. [Article] A Small Parasite Making Big Waves: Industry Consolidation and Collaboration under Spatial-Dynamic Externalities

  Parasites and diseases represent major challenges in aquaculture. In the Norwegian salmon farming industry, costs associated with treatment of sea lice are surging and reached 5bn NOK or 10% of the industry’s ...

  Citation × Citation Citation Abstract Copy Title: A Small Parasite Making Big Waves: Industry Consolidation and Collaboration under Spatial-Dynamic Externalities Author: Abbott, Joshua, Morency-Lavoie, Félix, Nøstbakken, Linda Parasites and diseases represent major challenges in aquaculture. In the Norwegian salmon farming industry, costs associated with treatment of sea lice are surging and reached 5bn NOK or 10% of the industry’s total export value in 2015. In addition to the direct impact on production, sea lice affect the industry indirectly through stricter regulations and monitoring requirements. Another feature of the Norwegian salmon farming industry is increasing consolidation ever since the deregulation in the early 1990s. In this paper, we investigate whether and to which extent consolidation is driven by a desire to internalize the spatial disease and parasite externality. Theory suggests that such intra-industry spatial externalities create incentives both for mergers and acquisitions, or spatial cooperation, to increase coordination in pest management. Using spatial techniques to capture the geographical spread and density of sea lice, we estimate the spatial dependencies between neighboring farms. The analysis rests on a novel and unique dataset regrouping high frequency biological and financial information at the farm and company level, with industry-wide history of mergers and acquisition as well as of collaboration in the form of joint production. Using this dataset, we are able to identify the impact of sea lice and other pathogens on the structure and behavior of the industry.  Title: A Small Parasite Making Big Waves: Industry Consolidation and Collaboration under Spatial-Dynamic Externalities Author: Abbott, Joshua, Morency-Lavoie, Félix, Nøstbakken, Linda Parasites and diseases represent major challenges in aquaculture. In the Norwegian salmon farming industry, costs associated with treatment of sea lice are surging and reached 5bn NOK or 10% of the industry’s total export value in 2015. In addition to the direct impact on production, sea lice affect the industry indirectly through stricter regulations and monitoring requirements. Another feature of the Norwegian salmon farming industry is increasing consolidation ever since the deregulation in the early 1990s. In this paper, we investigate whether and to which extent consolidation is driven by a desire to internalize the spatial disease and parasite externality. Theory suggests that such intra-industry spatial externalities create incentives both for mergers and acquisitions, or spatial cooperation, to increase coordination in pest management. Using spatial techniques to capture the geographical spread and density of sea lice, we estimate the spatial dependencies between neighboring farms. The analysis rests on a novel and unique dataset regrouping high frequency biological and financial information at the farm and company level, with industry-wide history of mergers and acquisition as well as of collaboration in the form of joint production. Using this dataset, we are able to identify the impact of sea lice and other pathogens on the structure and behavior of the industry.  Close

• 5. [Article] The Value of Eco-Labels through Revealed Consumer Preferences for Seafood in San Diego County

  Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), ...

  Citation × Citation Citation Abstract Copy Title: The Value of Eco-Labels through Revealed Consumer Preferences for Seafood in San Diego County Author: Poindexter, Oriana Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Title: The Value of Eco-Labels through Revealed Consumer Preferences for Seafood in San Diego County Author: Poindexter, Oriana Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Close

• 6. [Article] Reference Points for Vulnerable Fish Species Based on Bioeconomic Age-Structured Models: An Approach for Totoaba macdonaldi

  Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), ...

  Citation × Citation Citation Abstract Copy Title: Reference Points for Vulnerable Fish Species Based on Bioeconomic Age-Structured Models: An Approach for Totoaba macdonaldi Author: María Da-Rocha, José, Hernández-Flores, Alvaro, De Anda-Montañez, Juan Antonio, Salas-Márquez, Silvia, Rodríguez-García, Oswaldo Uriel, Valenzuela-Quiñonez, Fausto Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Title: Reference Points for Vulnerable Fish Species Based on Bioeconomic Age-Structured Models: An Approach for Totoaba macdonaldi Author: María Da-Rocha, José, Hernández-Flores, Alvaro, De Anda-Montañez, Juan Antonio, Salas-Márquez, Silvia, Rodríguez-García, Oswaldo Uriel, Valenzuela-Quiñonez, Fausto Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Close

• 7. [Article] Measuring the Value of Forage Fish to Recreational Fishermen

  Fisheries management has been traditionally single-species oriented. Only recently more pressure has been put on developing a holistic, science-based approach that considers the ecosystem as a whole. This ...

  Citation × Citation Citation Abstract Copy Title: Measuring the Value of Forage Fish to Recreational Fishermen Author: Lipton, Doug, Hutniczak, Barbara, Townsend, Howard Fisheries management has been traditionally single-species oriented. Only recently more pressure has been put on developing a holistic, science-based approach that considers the ecosystem as a whole. This approach is widely known as ecosystem-based fisheries management (EBFM). One of the most often highlighted aspects of EBFM is the relevance of predator-prey interactions in the aquatic ecosystems. The motivation is that there are considerable trade-offs between the supporting role of forage species as energy conveyors in food webs and provisioning service as target species to fisheries. We study this aspect by looking at the Chesapeake Bay. The motivation is a recent debate on the potential impact of excessive forage base fishing. In particular, we are interested in the propagation of forage overfishing through the food web and its influence on more valuable, higher trophic species fisheries. We develop a Bayesian model of recreational harvest of striped bass where benefits are derived from stock size as well as age structure. The age structure drives the probability of catching a fish of a particular size what is of considerable importance to the fishery highly constrained by minimum catch size regulations. Then, using a dynamic multispecies framework (Ecosim) and modified random utility model, we analyze multiple scenarios varying by menhaden regulations and derive benefits changes imposed on the striped bass recreational fishery. We focus on the recreational sector as recent research indicates that the recreational fishing is becoming increasingly important and new management strategies may be necessary to address this shifting trend. Title: Measuring the Value of Forage Fish to Recreational Fishermen Author: Lipton, Doug, Hutniczak, Barbara, Townsend, Howard Fisheries management has been traditionally single-species oriented. Only recently more pressure has been put on developing a holistic, science-based approach that considers the ecosystem as a whole. This approach is widely known as ecosystem-based fisheries management (EBFM). One of the most often highlighted aspects of EBFM is the relevance of predator-prey interactions in the aquatic ecosystems. The motivation is that there are considerable trade-offs between the supporting role of forage species as energy conveyors in food webs and provisioning service as target species to fisheries. We study this aspect by looking at the Chesapeake Bay. The motivation is a recent debate on the potential impact of excessive forage base fishing. In particular, we are interested in the propagation of forage overfishing through the food web and its influence on more valuable, higher trophic species fisheries. We develop a Bayesian model of recreational harvest of striped bass where benefits are derived from stock size as well as age structure. The age structure drives the probability of catching a fish of a particular size what is of considerable importance to the fishery highly constrained by minimum catch size regulations. Then, using a dynamic multispecies framework (Ecosim) and modified random utility model, we analyze multiple scenarios varying by menhaden regulations and derive benefits changes imposed on the striped bass recreational fishery. We focus on the recreational sector as recent research indicates that the recreational fishing is becoming increasingly important and new management strategies may be necessary to address this shifting trend. Close