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• 31. [Article] Adaptive genetic markers discriminate migratory runs of Chinook salmon (Oncorhynchus tshawytscha) amid continued gene flow

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/jo...

  Citation × Citation Citation Abstract Copy Title: Adaptive genetic markers discriminate migratory runs of Chinook salmon (Oncorhynchus tshawytscha) amid continued gene flow Author: Jacobson, Dave P., Banks, Michael A., Dill, Allen J., Kurth, Ryon, O'Malley, Kathleen G. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1752-4571. Title: Adaptive genetic markers discriminate migratory runs of Chinook salmon (Oncorhynchus tshawytscha) amid continued gene flow Author: Jacobson, Dave P., Banks, Michael A., Dill, Allen J., Kurth, Ryon, O'Malley, Kathleen G. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1752-4571. Close

• 32. [Article] Use of Genetic Stock Identification Data for Comparison of the Ocean Spatial Distribution, Size at Age, and Fishery Exposure of an Untagged Stock and Its Indicator: California Coastal versus Klamath River Chinook Salmon

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the American Fisheries ...

  Citation × Citation Citation Abstract Copy Title: Use of Genetic Stock Identification Data for Comparison of the Ocean Spatial Distribution, Size at Age, and Fishery Exposure of an Untagged Stock and Its Indicator: California Coastal versus Klamath River Chinook Salmon Author: Mohr, Michael S., Banks, Michael A., Borgerson, Lisa A., Lawson, Peter W., Anderson, Eric C., Garza, John Carlos, Crandall, Eric D., Satterthwaite, William H., O'Farrell, Michael R., Bellinger, M. Renee, Palmer-Zwahlen, Melodie L., Bates, Sarah J., Kormos, Brett J. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the American Fisheries Society and published by Taylor & Francis. It can be found at: http://www.tandfonline.com/toc/utaf20/current#.UzNNkfPn-Hs. Title: Use of Genetic Stock Identification Data for Comparison of the Ocean Spatial Distribution, Size at Age, and Fishery Exposure of an Untagged Stock and Its Indicator: California Coastal versus Klamath River Chinook Salmon Author: Mohr, Michael S., Banks, Michael A., Borgerson, Lisa A., Lawson, Peter W., Anderson, Eric C., Garza, John Carlos, Crandall, Eric D., Satterthwaite, William H., O'Farrell, Michael R., Bellinger, M. Renee, Palmer-Zwahlen, Melodie L., Bates, Sarah J., Kormos, Brett J. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the American Fisheries Society and published by Taylor & Francis. It can be found at: http://www.tandfonline.com/toc/utaf20/current#.UzNNkfPn-Hs. Close

• 33. [Article] Testing advances in molecular discrimination among Chinook salmon life histories: evidence from a blind test

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the author(s) ...

  Citation × Citation Citation Abstract Copy Title: Testing advances in molecular discrimination among Chinook salmon life histories: evidence from a blind test Author: Banks, Michael A., Ardren, William R., Bernier-Latmani, Jeremiah, Meusnier, Isabelle, Van Sickle, John, Rashbrook, Vanessa K., Jacobson, David P., Smith, Christian T., O'Malley, Kathleen G., Greig, Carolyn A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2052. Title: Testing advances in molecular discrimination among Chinook salmon life histories: evidence from a blind test Author: Banks, Michael A., Ardren, William R., Bernier-Latmani, Jeremiah, Meusnier, Isabelle, Van Sickle, John, Rashbrook, Vanessa K., Jacobson, David P., Smith, Christian T., O'Malley, Kathleen G., Greig, Carolyn A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2052. Close

• 34. [Article] Neural gene expression profiling in chinook salmon (Oncorhynchus tshawytscha) of alternate run times

  Chinook salmon (Oncorhynchus tshawytscha) display the greatest variability of return times to freshwater of all Pacific salmon. Differential return times to freshwater have segregated populations of ...

  Citation × Citation Citation Abstract Copy Title: Neural gene expression profiling in chinook salmon (Oncorhynchus tshawytscha) of alternate run times Author: Bernier, Jeremiah C. Chinook salmon (Oncorhynchus tshawytscha) display the greatest variability of return times to freshwater of all Pacific salmon. Differential return times to freshwater have segregated populations of Chinook into two broad types or runs, fall and spring, named for the time of year in which they migrate to freshwater. Migration time in Chinook has a strong genetic component, and historically, fall and spring runs were spatially and temporally isolated in watersheds. Using a population of Chinook from California’s Central Valley, I sought to examine gene regulation that results in differential run-timing. Functional genomics has proven to be powerful in distinguishing genes differentially expressed between alternate behaviors in other systems and I used the technique LongSAGE to examine genes differentially regulated between fall and spring run Chinook during freshwater migration. I constructed three LongSAGE libraries from the brains of a spring, fall and ocean sample and observed 221 differentially expressed tags. Using expressed sequence tag (EST) libraries from Atlantic salmon (Salmo salar) and rainbow trout (O. mykiss), I was able to assign putative functions to 59% of differentially expressed tags. Additionally, I tested the expression levels of seven genes in the brains of 8 additional individuals from both runs and found none significantly differentially expressed between fall and spring runs. This study is the first to apply LongSAGE to salmon and provides a framework for conducting future gene expression research into reproduction and migration times, as well as physiology of migrating salmon. Title: Neural gene expression profiling in chinook salmon (Oncorhynchus tshawytscha) of alternate run times Author: Bernier, Jeremiah C. Chinook salmon (Oncorhynchus tshawytscha) display the greatest variability of return times to freshwater of all Pacific salmon. Differential return times to freshwater have segregated populations of Chinook into two broad types or runs, fall and spring, named for the time of year in which they migrate to freshwater. Migration time in Chinook has a strong genetic component, and historically, fall and spring runs were spatially and temporally isolated in watersheds. Using a population of Chinook from California’s Central Valley, I sought to examine gene regulation that results in differential run-timing. Functional genomics has proven to be powerful in distinguishing genes differentially expressed between alternate behaviors in other systems and I used the technique LongSAGE to examine genes differentially regulated between fall and spring run Chinook during freshwater migration. I constructed three LongSAGE libraries from the brains of a spring, fall and ocean sample and observed 221 differentially expressed tags. Using expressed sequence tag (EST) libraries from Atlantic salmon (Salmo salar) and rainbow trout (O. mykiss), I was able to assign putative functions to 59% of differentially expressed tags. Additionally, I tested the expression levels of seven genes in the brains of 8 additional individuals from both runs and found none significantly differentially expressed between fall and spring runs. This study is the first to apply LongSAGE to salmon and provides a framework for conducting future gene expression research into reproduction and migration times, as well as physiology of migrating salmon. Close

• 35. [Article] The relationships between fluctuations in oceanographic conditions, forage fishes, predatory fishes, predator food habits, and juvenile salmonid marine survival off the Columbia River

  Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other ...

  Citation × Citation Citation Abstract Copy Title: The relationships between fluctuations in oceanographic conditions, forage fishes, predatory fishes, predator food habits, and juvenile salmonid marine survival off the Columbia River Author: Emmett, Robert L. Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other fishes. Changes in the biological and physical environment off the Columbia River region affects the distribution and abundance of predatory fishes and their feeding, forage fishes, and juvenile salmonid marine survival. From 1998-2004, forage fish and predatory fish distribution and abundance off the Columbia River was quantified by surface trawling at night during spring/summer. The effect of predation on salmonids was measured by stomach analysis of predatory fishes. During the study period (1998-2004), forage fishes increased in abundance by orders of magnitude and were strongly related to the abundance of cold-water copepods the previous year. Higher forage fish populations were also linked to cooler ocean conditions and perhaps fewer predatory Pacific hake (Merluccius productus). Most forage fishes were distributed nearshore while predators had a more offshore distribution. Pacific hake was most abundant in 1998, 2003, and 2004; warm ocean years. Jack mackerel (Trachurus symmetricus) was most abundant during 1999-2002; relatively cool ocean years. Deep (50-m) ocean temperatures and the date of the spring transition, when nearshore currents switched from northward to southward, were good predictors of Pacific hake abundance in the study area. Forage fish or salmonid occurrence in a haul was negatively related to the occurrence of predators. Pacific hake and jack mackerel ate primarily euphausiids and small fishes. Salmonids were rarely eaten by either predator. However, because the Pacific hake population can be very large, hake predation can be a significant source of juvenile salmon mortality off the Columbia River during some years. A trophic model showed that marine mortality of Columbia River juvenile salmonids may be related to the abundance of Pacific hake and forage fishes. A multiple regression using the predictions from the trophic model of annual numbers of juvenile salmonids eaten by hake and Columbia River spring flows as independent variables, accounted for much of the variation observed in the annual marine survival of Columbia River coho (Oncorhynchus kisutch) and Chinook salmon (O. tshawytscha), the dependent variable. Future research should identify the physical and biological forces that alter the feeding habits, migration and movements of Pacific hake and jack mackerel off the Northwest, and how Columbia River flows affect trophic interactions. Title: The relationships between fluctuations in oceanographic conditions, forage fishes, predatory fishes, predator food habits, and juvenile salmonid marine survival off the Columbia River Author: Emmett, Robert L. Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other fishes. Changes in the biological and physical environment off the Columbia River region affects the distribution and abundance of predatory fishes and their feeding, forage fishes, and juvenile salmonid marine survival. From 1998-2004, forage fish and predatory fish distribution and abundance off the Columbia River was quantified by surface trawling at night during spring/summer. The effect of predation on salmonids was measured by stomach analysis of predatory fishes. During the study period (1998-2004), forage fishes increased in abundance by orders of magnitude and were strongly related to the abundance of cold-water copepods the previous year. Higher forage fish populations were also linked to cooler ocean conditions and perhaps fewer predatory Pacific hake (Merluccius productus). Most forage fishes were distributed nearshore while predators had a more offshore distribution. Pacific hake was most abundant in 1998, 2003, and 2004; warm ocean years. Jack mackerel (Trachurus symmetricus) was most abundant during 1999-2002; relatively cool ocean years. Deep (50-m) ocean temperatures and the date of the spring transition, when nearshore currents switched from northward to southward, were good predictors of Pacific hake abundance in the study area. Forage fish or salmonid occurrence in a haul was negatively related to the occurrence of predators. Pacific hake and jack mackerel ate primarily euphausiids and small fishes. Salmonids were rarely eaten by either predator. However, because the Pacific hake population can be very large, hake predation can be a significant source of juvenile salmon mortality off the Columbia River during some years. A trophic model showed that marine mortality of Columbia River juvenile salmonids may be related to the abundance of Pacific hake and forage fishes. A multiple regression using the predictions from the trophic model of annual numbers of juvenile salmonids eaten by hake and Columbia River spring flows as independent variables, accounted for much of the variation observed in the annual marine survival of Columbia River coho (Oncorhynchus kisutch) and Chinook salmon (O. tshawytscha), the dependent variable. Future research should identify the physical and biological forces that alter the feeding habits, migration and movements of Pacific hake and jack mackerel off the Northwest, and how Columbia River flows affect trophic interactions. Close

• 36. [Article] Economic evaluation of projects and policies affecting anadromous fish : a simulation approach

  Anadromous fish populations in the Pacific Northwest have undergone substantial change throughout the past century. Historical periods of over-harvest and the construction of numerous dams throughout the ...

  Citation × Citation Citation Abstract Copy Title: Economic evaluation of projects and policies affecting anadromous fish : a simulation approach Author: Hastie, James D. Anadromous fish populations in the Pacific Northwest have undergone substantial change throughout the past century. Historical periods of over-harvest and the construction of numerous dams throughout the region have contributed to declines in the runs of naturally spawning stocks. Management efforts to rebuild fish populations have focused on the restriction of harvest activities and the release of hatchery-reared salmon. A microcomputer simulation model is developed to estimate the economic impacts of management alternatives. In it, fish are passed throughout a network of nodes, according to parameters governing mortality and harvest. These parameters, and the node structure itself, are provided to the model by a user-specified input file. As a result, the model affords flexibility in meeting the modeling needs of differing salmonid stocks. The model's economic assessment capabilities are demonstrated through a case study of Rogue River spring chinook. Results of this exercise include estimates for the impacts of dam construction, hatchery releases, and changes in ocean and river harvest policies on the social value derived from harvest activities. The research also examines the redistribution of economic benefits associated with these policies. The impact of a recently constructed dam upon spring chinook fishermen is estimated at a loss of more than $10,600,000 over thirty years, given no hatchery supplementation. Current hatchery programs have mitigated the loss to fishermen, but whether they also offset their operating costs depends upon the particular harvest values employed. The value of providing an additional wild spawner to the basin is estimated to be roughly $300. Examination of various harvest alternatives indicates that restrictions placed on the commercial ocean fishery would be more successful in increasing the present value of harvests than would similar restrictions in the sport fishery. An important factor in this outcome is the higher value attributed to sport catch by currently accepted methods of valuation. Suggestions are made for improvements to the simulation model and the availability of information for use with it. Foremost among these is the need for improved specification of the marginal social value derived from salmon harvested in commercial and recreational fisheries. Title: Economic evaluation of projects and policies affecting anadromous fish : a simulation approach Author: Hastie, James D. Anadromous fish populations in the Pacific Northwest have undergone substantial change throughout the past century. Historical periods of over-harvest and the construction of numerous dams throughout the region have contributed to declines in the runs of naturally spawning stocks. Management efforts to rebuild fish populations have focused on the restriction of harvest activities and the release of hatchery-reared salmon. A microcomputer simulation model is developed to estimate the economic impacts of management alternatives. In it, fish are passed throughout a network of nodes, according to parameters governing mortality and harvest. These parameters, and the node structure itself, are provided to the model by a user-specified input file. As a result, the model affords flexibility in meeting the modeling needs of differing salmonid stocks. The model's economic assessment capabilities are demonstrated through a case study of Rogue River spring chinook. Results of this exercise include estimates for the impacts of dam construction, hatchery releases, and changes in ocean and river harvest policies on the social value derived from harvest activities. The research also examines the redistribution of economic benefits associated with these policies. The impact of a recently constructed dam upon spring chinook fishermen is estimated at a loss of more than $10,600,000 over thirty years, given no hatchery supplementation. Current hatchery programs have mitigated the loss to fishermen, but whether they also offset their operating costs depends upon the particular harvest values employed. The value of providing an additional wild spawner to the basin is estimated to be roughly $300. Examination of various harvest alternatives indicates that restrictions placed on the commercial ocean fishery would be more successful in increasing the present value of harvests than would similar restrictions in the sport fishery. An important factor in this outcome is the higher value attributed to sport catch by currently accepted methods of valuation. Suggestions are made for improvements to the simulation model and the availability of information for use with it. Foremost among these is the need for improved specification of the marginal social value derived from salmon harvested in commercial and recreational fisheries. Close

• 37. [Article] An investigation into the genetic basis of migration timing in Chinook salmon (Oncorhynchus tshawytscha)

  The genetic basis of adaptation is complex as many fitness-related traits are quantitative and likely influenced by multiple genes with variable effects across different selective environments. One important ...

  Citation × Citation Citation Abstract Copy Title: An investigation into the genetic basis of migration timing in Chinook salmon (Oncorhynchus tshawytscha) Author: O'Malley, Kathleen Gallen, 1976- The genetic basis of adaptation is complex as many fitness-related traits are quantitative and likely influenced by multiple genes with variable effects across different selective environments. One important adaptation for anadromous Chinook salmon (Oncorhynchus tshawytscha) is the time at which individuals return to natal breeding sites within a reproductive season. Here, I tested for adaptive genetic differentiation among temporally divergent migratory runs using candidate loci. First, I isolated and characterized two copies of the circadian rhythm gene, Clock, from Chinook salmon (OtsClock1a and OtsClock1b). Phylogenetic analysis revealed that these copies likely arose subsequent to the salmonid genome-wide duplication event. Each copy contains a polyglutamine repeat motif (PolyQ), an essential binding domain of this transcription factor. However, a 1200bp non-coding segment, showing >90% sequence identity to the Salmo salar Transferrin gene, is located downstream of the OtsClock1a PolyQ, yet absent from OtsClock1b providing evidence for nonhomologous recombination. Another candidate, Ots515NWFSC, shows sequence identity to three salmonid genes central to reproductive development: Gonadotropin-releasing hormone, CYP19b-I, and Ghrelin. I employed OtsClock1b and Ots515NWFSC to test for differentiation in two unique systems: Feather River, California; and Waitaki and Poulter Rivers, New Zealand. Based on length variation in these candidate genes, Feather River fall and spring run Chinook salmon are genetically differentiated. In contrast, these seasonal runs are genetically indistinguishable based on neutral microsatellite loci. Correspondingly, temporally divergent Chinook salmon runs in the Waitaki and Poulter Rivers show greater differentiation based on variation in OtsClock1b and Ots515NWFSC than microsatellite loci. Tests for selective neutrality indicate that OtsClock1b and Ots515NWFSC are likely under selection in both systems. In addition, I found evidence for a latitudinal cline in two OtsClock1b PolyQ alleles among 42 Chinook salmon runs which is likely maintained by selection and thus may reflect an adaptation to photoperiodic parameters. Lastly, a hierarchical gene diversity analysis of OtsClock1b PolyQ variation revealed that run timing explained 43.7% of the overall genetic variance which contrast sharply with the 8.1% calculated for microsatellite loci. Evidence presented here suggests that OtsClock1b and Ots515NWFSC may influence migration timing of Chinook salmon. Title: An investigation into the genetic basis of migration timing in Chinook salmon (Oncorhynchus tshawytscha) Author: O'Malley, Kathleen Gallen, 1976- The genetic basis of adaptation is complex as many fitness-related traits are quantitative and likely influenced by multiple genes with variable effects across different selective environments. One important adaptation for anadromous Chinook salmon (Oncorhynchus tshawytscha) is the time at which individuals return to natal breeding sites within a reproductive season. Here, I tested for adaptive genetic differentiation among temporally divergent migratory runs using candidate loci. First, I isolated and characterized two copies of the circadian rhythm gene, Clock, from Chinook salmon (OtsClock1a and OtsClock1b). Phylogenetic analysis revealed that these copies likely arose subsequent to the salmonid genome-wide duplication event. Each copy contains a polyglutamine repeat motif (PolyQ), an essential binding domain of this transcription factor. However, a 1200bp non-coding segment, showing >90% sequence identity to the Salmo salar Transferrin gene, is located downstream of the OtsClock1a PolyQ, yet absent from OtsClock1b providing evidence for nonhomologous recombination. Another candidate, Ots515NWFSC, shows sequence identity to three salmonid genes central to reproductive development: Gonadotropin-releasing hormone, CYP19b-I, and Ghrelin. I employed OtsClock1b and Ots515NWFSC to test for differentiation in two unique systems: Feather River, California; and Waitaki and Poulter Rivers, New Zealand. Based on length variation in these candidate genes, Feather River fall and spring run Chinook salmon are genetically differentiated. In contrast, these seasonal runs are genetically indistinguishable based on neutral microsatellite loci. Correspondingly, temporally divergent Chinook salmon runs in the Waitaki and Poulter Rivers show greater differentiation based on variation in OtsClock1b and Ots515NWFSC than microsatellite loci. Tests for selective neutrality indicate that OtsClock1b and Ots515NWFSC are likely under selection in both systems. In addition, I found evidence for a latitudinal cline in two OtsClock1b PolyQ alleles among 42 Chinook salmon runs which is likely maintained by selection and thus may reflect an adaptation to photoperiodic parameters. Lastly, a hierarchical gene diversity analysis of OtsClock1b PolyQ variation revealed that run timing explained 43.7% of the overall genetic variance which contrast sharply with the 8.1% calculated for microsatellite loci. Evidence presented here suggests that OtsClock1b and Ots515NWFSC may influence migration timing of Chinook salmon. Close

• 38. [Article] A methodology for evaluating the economic impact on directed fisheries of by-catch losses in the foreign and joint-venture groundfish fisheries

  The principal objective of this analysis is the development of a methodological approach that would permit a more complete evaluation of the physical and economic consequences of prohibited species by-catch (PSC) ...

  Citation × Citation Citation Abstract Copy Title: A methodology for evaluating the economic impact on directed fisheries of by-catch losses in the foreign and joint-venture groundfish fisheries Author: Queirolo, Lewis E. The principal objective of this analysis is the development of a methodological approach that would permit a more complete evaluation of the physical and economic consequences of prohibited species by-catch (PSC) losses, such as occur in the harvest of groundfish. To achieve efficient management of the several marine species involved in the groundfish and associated PSC controversy, U.S. regulatory authorities sought to obtain estimates of the probable economic and physical impacts attributable to these harvesting activities. Early efforts were based upon the assumption that all PSC losses would have accrued to directed fisheries in the year subsequent to that in which the by-caught specimen would have been legally harvestable. The present analysis hypothesizes that substantial latent economic costs, associated with foregone reproductive potential, are also attributable to PSC losses and incorrectly ignored by previous assessment methodologies. To test this assertion an alternative methodology was developed and empirically applied to the case of Pacific salmon PSCs in the Gulf of Alaska groundfish fisheries. The empirical results demonstrate the presence of substantial latent losses associated with salmon PSC reproductive potential foregone. Although preliminary, these results confirm the presence of the hypothesized long run adverse economic impacts on directed salmon fisheries associated with a single season's PSC interception. Similar results would be expected in the case of Pacific halibut, king crab, and Tanner crab, although substantial research on the biological impacts of PSC losses on these species remains to be done. Refinement of the economic components of the proposed model and improvement of the primary data upon which it relies will, likewise, involve substantial investments in further research. Title: A methodology for evaluating the economic impact on directed fisheries of by-catch losses in the foreign and joint-venture groundfish fisheries Author: Queirolo, Lewis E. The principal objective of this analysis is the development of a methodological approach that would permit a more complete evaluation of the physical and economic consequences of prohibited species by-catch (PSC) losses, such as occur in the harvest of groundfish. To achieve efficient management of the several marine species involved in the groundfish and associated PSC controversy, U.S. regulatory authorities sought to obtain estimates of the probable economic and physical impacts attributable to these harvesting activities. Early efforts were based upon the assumption that all PSC losses would have accrued to directed fisheries in the year subsequent to that in which the by-caught specimen would have been legally harvestable. The present analysis hypothesizes that substantial latent economic costs, associated with foregone reproductive potential, are also attributable to PSC losses and incorrectly ignored by previous assessment methodologies. To test this assertion an alternative methodology was developed and empirically applied to the case of Pacific salmon PSCs in the Gulf of Alaska groundfish fisheries. The empirical results demonstrate the presence of substantial latent losses associated with salmon PSC reproductive potential foregone. Although preliminary, these results confirm the presence of the hypothesized long run adverse economic impacts on directed salmon fisheries associated with a single season's PSC interception. Similar results would be expected in the case of Pacific halibut, king crab, and Tanner crab, although substantial research on the biological impacts of PSC losses on these species remains to be done. Refinement of the economic components of the proposed model and improvement of the primary data upon which it relies will, likewise, involve substantial investments in further research. Close

• 39. [Article] Measuring recreational fishing benefits in a multiple site framework : a case study of the Willamette spring chinook sports fishery

  The management options chosen by decision makers in managing wildlife and fisheries have different effects for diverse user groups. As a result, natural resource management agencies often seek information ...

  Citation × Citation Citation Abstract Copy Title: Measuring recreational fishing benefits in a multiple site framework : a case study of the Willamette spring chinook sports fishery Author: Lin, Pei-Chien The management options chosen by decision makers in managing wildlife and fisheries have different effects for diverse user groups. As a result, natural resource management agencies often seek information to evaluate the effects of alternative policies on the benefits provided to different constituencies. Over the past decade, economists have developed techniques to measure the benefits provided by such nonmarket goods. The random utility model (RUM), a variant of the travel cost model (TCM), is one of the techniques developed by economists to measure benefits associated with changes in the quantity or quality of nonmarket goods. The advantages of using RUN over other techniques are that the substitution effects among different sites providing similar recreational activities or services can be incorporated into the model to avoid overestimating the benefits provided by a certain site. Redacted for Privacy RUM is used in this thesis to measure the welfare changes caused by a reduction in fishing quality or closure of one of the sites in a recreational fishing area. The focus of this study is the spring chinook recreational fishery in the lower Willamette River. The 1988 Willamette Run Spring Chinook Survey and the 1988 Willamette River Spring Chinook Salmon Run Report, published by the Oregon Department of Fish and Wildlife, provide the data set to do this research. Three definitions of travel costs, TC1, TC2, and TC3 are derived from the data set and used alternatively in the RUM framework. Specific objectives of this thesis include: (1) estimate how the attributes of a site (travel cost, congestion level and fishing quality of the site) will affect the individual's site choice; and (2) estimate the welfare changes arising from the two hypothetical policies which change the quality of fishing experience and which restrict the access of anglers to a certain fishing site. The results indicate that fishing sites on the Willamette River are more attractive to anglers if the fishing quality is increased, if more people visit, and if the site is relatively inexpensive to reach. The results of the elasticities of probabilities show that the travel cost has the largest effect on individual site choice decision. For different definitions of travel costs, the estimated welfare losses caused by the first hypothetical policy (of a reduction in fishing. success) for a representative angler in the sample are $ 0.37, $ 0.91, and $ 0.47 respectively, per trip. For different definitions of travel costs, the aggregate welfare losses associated with this hypothetical policy are $ 82,309, $ 202,436, and $ 104,555. For different definitions of travel costs, the estimated welfare losses caused by the second hypothetical policy (a closure of one site) for a representative angler in the sample are $ 3.82, $ 54.91, and $ 4.83 per trip respectively. The aggregate welfare losses associated with this hypothetical policy are $ 849,786, $ 12,215,114, and $ 1,074,467 respectively for TC1, TC2, and TC3. Assuming that these two policies achieved the same objectives, the policy implication of these results is that the first policy is preferred because the welfare loss is much smaller than the second one. There is a methodological implication suggested by one of the findings. A few of the individual results obtained from the model with TC2 travel cost violate the assumption of utility maximization. This implies that TC2 may over-value the opportunity cost of time in the travel cost variable, and points out the uncertain of the definition of travel cost used in RUM analyses. Title: Measuring recreational fishing benefits in a multiple site framework : a case study of the Willamette spring chinook sports fishery Author: Lin, Pei-Chien The management options chosen by decision makers in managing wildlife and fisheries have different effects for diverse user groups. As a result, natural resource management agencies often seek information to evaluate the effects of alternative policies on the benefits provided to different constituencies. Over the past decade, economists have developed techniques to measure the benefits provided by such nonmarket goods. The random utility model (RUM), a variant of the travel cost model (TCM), is one of the techniques developed by economists to measure benefits associated with changes in the quantity or quality of nonmarket goods. The advantages of using RUN over other techniques are that the substitution effects among different sites providing similar recreational activities or services can be incorporated into the model to avoid overestimating the benefits provided by a certain site. Redacted for Privacy RUM is used in this thesis to measure the welfare changes caused by a reduction in fishing quality or closure of one of the sites in a recreational fishing area. The focus of this study is the spring chinook recreational fishery in the lower Willamette River. The 1988 Willamette Run Spring Chinook Survey and the 1988 Willamette River Spring Chinook Salmon Run Report, published by the Oregon Department of Fish and Wildlife, provide the data set to do this research. Three definitions of travel costs, TC1, TC2, and TC3 are derived from the data set and used alternatively in the RUM framework. Specific objectives of this thesis include: (1) estimate how the attributes of a site (travel cost, congestion level and fishing quality of the site) will affect the individual's site choice; and (2) estimate the welfare changes arising from the two hypothetical policies which change the quality of fishing experience and which restrict the access of anglers to a certain fishing site. The results indicate that fishing sites on the Willamette River are more attractive to anglers if the fishing quality is increased, if more people visit, and if the site is relatively inexpensive to reach. The results of the elasticities of probabilities show that the travel cost has the largest effect on individual site choice decision. For different definitions of travel costs, the estimated welfare losses caused by the first hypothetical policy (of a reduction in fishing. success) for a representative angler in the sample are $ 0.37, $ 0.91, and $ 0.47 respectively, per trip. For different definitions of travel costs, the aggregate welfare losses associated with this hypothetical policy are $ 82,309, $ 202,436, and $ 104,555. For different definitions of travel costs, the estimated welfare losses caused by the second hypothetical policy (a closure of one site) for a representative angler in the sample are $ 3.82, $ 54.91, and $ 4.83 per trip respectively. The aggregate welfare losses associated with this hypothetical policy are $ 849,786, $ 12,215,114, and $ 1,074,467 respectively for TC1, TC2, and TC3. Assuming that these two policies achieved the same objectives, the policy implication of these results is that the first policy is preferred because the welfare loss is much smaller than the second one. There is a methodological implication suggested by one of the findings. A few of the individual results obtained from the model with TC2 travel cost violate the assumption of utility maximization. This implies that TC2 may over-value the opportunity cost of time in the travel cost variable, and points out the uncertain of the definition of travel cost used in RUM analyses. Close

• 40. [Article] Salmon recovery in the Pacific Northwest : defining what constitutes a wild salmon

  In spite of considerable efforts to restore natural runs of anadromous salmonids in the Pacific Northwest, they remain at risk of extirpation. Along with many other factors influencing the decline, stocking ...

  Citation × Citation Citation Abstract Copy Title: Salmon recovery in the Pacific Northwest : defining what constitutes a wild salmon Author: Courter, Ian I. In spite of considerable efforts to restore natural runs of anadromous salmonids in the Pacific Northwest, they remain at risk of extirpation. Along with many other factors influencing the decline, stocking from hatcheries over the past hundred years is often suggested to be a major cause. The listing of over two dozen runs of salmon under the Endangered Species Act has catalyzed a re-assessment of hatchery effects on naturally spawning salmon. Recent policies have placed a much greater emphasis on restoring runs of wild salmon rather than maintaining runs through stocking from hatchery production. Except at the most superficial level, there is no consensus about how to define "wild." Rather, there is a continuum of definitions for "wild" and each definition supports an implicit policy goal. The precise way in which "wild salmon" is defined potentially has profound policy implications. Ultimately, the choice of definition is a policy decision that incorporates science as one of several factors influencing the decision. A suite of options, often poorly articulated, for defining "wild" are available to policy makers who are selecting recovery goals. To test a subset of the available definitions of wild, I quantified the number of hatchery and naturally spawning salmon for 19 populations of Oregon coastal coho. "Wild" was defined by types 1 through 5 based on the number of hatchery fish released annually and the number of naturally spawning hatchery adults. As currently managed by the Oregon Department of Fish and Wildlife, the Oregon coast has a range of "types" of coho salmon. By clearly and explicitly defining "wild" as steps along a continuum, policy makers and managers can more effectively monitor and achieve specific salmon recovery goals. Title: Salmon recovery in the Pacific Northwest : defining what constitutes a wild salmon Author: Courter, Ian I. In spite of considerable efforts to restore natural runs of anadromous salmonids in the Pacific Northwest, they remain at risk of extirpation. Along with many other factors influencing the decline, stocking from hatcheries over the past hundred years is often suggested to be a major cause. The listing of over two dozen runs of salmon under the Endangered Species Act has catalyzed a re-assessment of hatchery effects on naturally spawning salmon. Recent policies have placed a much greater emphasis on restoring runs of wild salmon rather than maintaining runs through stocking from hatchery production. Except at the most superficial level, there is no consensus about how to define "wild." Rather, there is a continuum of definitions for "wild" and each definition supports an implicit policy goal. The precise way in which "wild salmon" is defined potentially has profound policy implications. Ultimately, the choice of definition is a policy decision that incorporates science as one of several factors influencing the decision. A suite of options, often poorly articulated, for defining "wild" are available to policy makers who are selecting recovery goals. To test a subset of the available definitions of wild, I quantified the number of hatchery and naturally spawning salmon for 19 populations of Oregon coastal coho. "Wild" was defined by types 1 through 5 based on the number of hatchery fish released annually and the number of naturally spawning hatchery adults. As currently managed by the Oregon Department of Fish and Wildlife, the Oregon coast has a range of "types" of coho salmon. By clearly and explicitly defining "wild" as steps along a continuum, policy makers and managers can more effectively monitor and achieve specific salmon recovery goals. Close