Search

Search Results

• 1. [Article] Measuring the Effects of Catch Shares: Identifying Indicators and Establishing Baselines along the West and Northeast Coasts

  The Measuring the Effects of Catch Shares Project is a webportal-based effort that continues to compile and analyze data on ecological, economic, social, and administrative changes in groundfish catch ...

  Citation × Citation Citation Abstract Copy Title: Measuring the Effects of Catch Shares: Identifying Indicators and Establishing Baselines along the West and Northeast Coasts Author: Downs, Michael A., Shug, Don, Hartley, Marcus, Weidlich, Stev The Measuring the Effects of Catch Shares Project is a webportal-based effort that continues to compile and analyze data on ecological, economic, social, and administrative changes in groundfish catch share fisheries on the West Coast and in the Northeast. The purpose of the five-year project is to make the best available data and accompanying analyses readily accessible to the general public as well as to those with specific interests the fisheries, including fishery managers, fishermen, policymakers, legislators, and service business owners. Among other data, the project presents information on six key economic and social indicators across both fisheries. This presentation describes the overall project, its goals, and initial findings. Specifically described are methodological considerations used in determining how and why a much larger number of potential indicators considered during project planning and initial baseline data gathering processes were winnowed down to the final key economic and social indicators. These considerations included the public availability of data, data accuracy, confidentiality, geographic coverage, and replicability, among others. Specifically underlined by the project findings is the importance of extended baseline time series data in placing potentially catch share-related changes in the context of longer-term fishery fluctuations and trends of change. Another preliminary conclusion is related to the challenges of confidentiality that severely restrict the analysis of changes at the sub-regional and/or port level, which is requiring implementation of additional methodologies in later stages of the project to address data gaps. Title: Measuring the Effects of Catch Shares: Identifying Indicators and Establishing Baselines along the West and Northeast Coasts Author: Downs, Michael A., Shug, Don, Hartley, Marcus, Weidlich, Stev The Measuring the Effects of Catch Shares Project is a webportal-based effort that continues to compile and analyze data on ecological, economic, social, and administrative changes in groundfish catch share fisheries on the West Coast and in the Northeast. The purpose of the five-year project is to make the best available data and accompanying analyses readily accessible to the general public as well as to those with specific interests the fisheries, including fishery managers, fishermen, policymakers, legislators, and service business owners. Among other data, the project presents information on six key economic and social indicators across both fisheries. This presentation describes the overall project, its goals, and initial findings. Specifically described are methodological considerations used in determining how and why a much larger number of potential indicators considered during project planning and initial baseline data gathering processes were winnowed down to the final key economic and social indicators. These considerations included the public availability of data, data accuracy, confidentiality, geographic coverage, and replicability, among others. Specifically underlined by the project findings is the importance of extended baseline time series data in placing potentially catch share-related changes in the context of longer-term fishery fluctuations and trends of change. Another preliminary conclusion is related to the challenges of confidentiality that severely restrict the analysis of changes at the sub-regional and/or port level, which is requiring implementation of additional methodologies in later stages of the project to address data gaps. Close

• 2. [Article] An Iterated Multiyear Simulation Model to Assess Impacts of Halibut Bycatch Limits

  Bering Sea/Aleutian Islands (BSAI) groundfish fisheries are hugely productive with 2008 – 2014 harvests averaging 1.6 million tons and generating $1.95 billion annually. The BSAI also hosts a commercial ...

  Citation × Citation Citation Abstract Copy Title: An Iterated Multiyear Simulation Model to Assess Impacts of Halibut Bycatch Limits Author: Hartley, Marcus Bering Sea/Aleutian Islands (BSAI) groundfish fisheries are hugely productive with 2008 – 2014 harvests averaging 1.6 million tons and generating $1.95 billion annually. The BSAI also hosts a commercial halibut fishery with 2013 landings of 3,500 tons and revenues of $41.5 million. Downward trends in halibut biomass combined with continued bycatch mortality in the groundfish fishery pushed the commercial harvests down to 2,000 tons in 2014, with lower harvest limits expected in 2015. Halibut bycatch mortality in the groundfish fisheries have exceeded commercial halibut harvests since 2012, and barring significant changes, bycatch will continue to exceed commercial harvests. An Iterated Multi-year Simulation (IMS) model was developed to assess future impacts to both the groundfish and commercial halibut fisheries of proposed reductions of up to 35 percent from current NMFS limits on bycatch mortality, established in the groundfish management plan. The IMS-model randomly selects from the basis years (2008 – 2013) to generate a simulated future from 2014 – 2023, in which the exploitable halibut biomass is held at 2014 estimates. Each randomly drawn year brings with it the halibut bycatch from that year, along with the groundfish harvests and revenue generated. Allowable future halibut harvests are estimated using the International Pacific Halibut Commission’s harvest policy algorithm, which nets out predicted bycatch mortality from exploitable biomass levels. After 10,000 iterations, the IMS-model yields distributions of expected bycatch and harvest levels, along with estimates of changes in the net present value of revenue over the 10-year future period for both the halibut and groundfish fisheries. Title: An Iterated Multiyear Simulation Model to Assess Impacts of Halibut Bycatch Limits Author: Hartley, Marcus Bering Sea/Aleutian Islands (BSAI) groundfish fisheries are hugely productive with 2008 – 2014 harvests averaging 1.6 million tons and generating $1.95 billion annually. The BSAI also hosts a commercial halibut fishery with 2013 landings of 3,500 tons and revenues of $41.5 million. Downward trends in halibut biomass combined with continued bycatch mortality in the groundfish fishery pushed the commercial harvests down to 2,000 tons in 2014, with lower harvest limits expected in 2015. Halibut bycatch mortality in the groundfish fisheries have exceeded commercial halibut harvests since 2012, and barring significant changes, bycatch will continue to exceed commercial harvests. An Iterated Multi-year Simulation (IMS) model was developed to assess future impacts to both the groundfish and commercial halibut fisheries of proposed reductions of up to 35 percent from current NMFS limits on bycatch mortality, established in the groundfish management plan. The IMS-model randomly selects from the basis years (2008 – 2013) to generate a simulated future from 2014 – 2023, in which the exploitable halibut biomass is held at 2014 estimates. Each randomly drawn year brings with it the halibut bycatch from that year, along with the groundfish harvests and revenue generated. Allowable future halibut harvests are estimated using the International Pacific Halibut Commission’s harvest policy algorithm, which nets out predicted bycatch mortality from exploitable biomass levels. After 10,000 iterations, the IMS-model yields distributions of expected bycatch and harvest levels, along with estimates of changes in the net present value of revenue over the 10-year future period for both the halibut and groundfish fisheries. Close