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• 41. [Article] Vertical distribution and migration of fishes from the lower mesopelagic zone off Oregon

  A 50 m² pelagic trawl equipped with a codend opening-closing device was used to sample micronektonic fishes between 500 m and 1000 m. Horizontal tows were made at 500, 650, 800 and 1000 m. Twelve of 15 ...

  Citation × Citation Citation Abstract Copy Title: Vertical distribution and migration of fishes from the lower mesopelagic zone off Oregon Author: Willis, John Marcus A 50 m² pelagic trawl equipped with a codend opening-closing device was used to sample micronektonic fishes between 500 m and 1000 m. Horizontal tows were made at 500, 650, 800 and 1000 m. Twelve of 15 common species captured showed significant diel differences in abundance at one or more depths indicative of vertical migration. Distinct vertical separation of day and night peaks in abundance of Bathylagus milleri shows that it migrates from 650 m during the day to 500 m at night. Catches of Cyclothone acclinidens and C. atraria were significantly higher during night than day at 800 m, suggesting upward migration from deeper depths at night. Several species showed changes in migratory behavior with size. Only small (<240 mm) Tactostoma macropus migrated vertically, whereas only large (>110 mm) Bathylagus pacificus appeared to migrate. Many species exhibited trends in size with depth, with size either increasing or decreasing with depth. Congeneric species usually had well separated population centers. Bathylagus mulleri and B. pacificus had similar abundance peaks by day, but B. milleri were shallower at night. Stenobrachius leucopsarus and S. nannochir were clearly separated vertically both day and night. The four common Cyclothone species were divided into an upper and a lower mesopelagic pair. Cyclothone pseudopallida and C. signata were most abundant at 500 m day and night, whereas C. acclinidens and C. atraria were most abundant at 800 m. All four common Cyclothone species appeared to migrate. Title: Vertical distribution and migration of fishes from the lower mesopelagic zone off Oregon Author: Willis, John Marcus A 50 m² pelagic trawl equipped with a codend opening-closing device was used to sample micronektonic fishes between 500 m and 1000 m. Horizontal tows were made at 500, 650, 800 and 1000 m. Twelve of 15 common species captured showed significant diel differences in abundance at one or more depths indicative of vertical migration. Distinct vertical separation of day and night peaks in abundance of Bathylagus milleri shows that it migrates from 650 m during the day to 500 m at night. Catches of Cyclothone acclinidens and C. atraria were significantly higher during night than day at 800 m, suggesting upward migration from deeper depths at night. Several species showed changes in migratory behavior with size. Only small (<240 mm) Tactostoma macropus migrated vertically, whereas only large (>110 mm) Bathylagus pacificus appeared to migrate. Many species exhibited trends in size with depth, with size either increasing or decreasing with depth. Congeneric species usually had well separated population centers. Bathylagus mulleri and B. pacificus had similar abundance peaks by day, but B. milleri were shallower at night. Stenobrachius leucopsarus and S. nannochir were clearly separated vertically both day and night. The four common Cyclothone species were divided into an upper and a lower mesopelagic pair. Cyclothone pseudopallida and C. signata were most abundant at 500 m day and night, whereas C. acclinidens and C. atraria were most abundant at 800 m. All four common Cyclothone species appeared to migrate. Close

• 42. [Article] Investigation of depleted uranium migration offsite from a military ordnance range : potential concentrations and radiological doses

  Citation × Citation Citation Abstract Copy Title: Investigation of depleted uranium migration offsite from a military ordnance range : potential concentrations and radiological doses Author: Rynders, David G. Title: Investigation of depleted uranium migration offsite from a military ordnance range : potential concentrations and radiological doses Author: Rynders, David G. Close

• 43. [Article] Factors influencing the seaward migration of smolt steelhead trout : Salmo gairdnerii gairdnerii Richardson, in the Alsea River, Oregon

  Citation × Citation Citation Abstract Copy Title: Factors influencing the seaward migration of smolt steelhead trout : Salmo gairdnerii gairdnerii Richardson, in the Alsea River, Oregon Author: Andrews, Rupert Earle Title: Factors influencing the seaward migration of smolt steelhead trout : Salmo gairdnerii gairdnerii Richardson, in the Alsea River, Oregon Author: Andrews, Rupert Earle Close

• 44. [Article] International students as educational migrants : east and southwest Asian perspectives

  Projected to reach one million people next year, international students in the United States are undergoing a transformative educational migration. Moving away from the existing study abroad paradigm is ...

  Citation × Citation Citation Abstract Copy Title: International students as educational migrants : east and southwest Asian perspectives Author: Visconti, Lauren A. Projected to reach one million people next year, international students in the United States are undergoing a transformative educational migration. Moving away from the existing study abroad paradigm is the first step to more accurately understand the lived experience of an educational migrant. Discovering the perceptions of what value an American education holds and accomplishes for students back home is central to revealing the major conditions and influences both propelling educational migration, the experience, and the course, features, and impacts of reentry migration. What prompts students to engage in this risky transformative activity? How can U.S. academic institutions better adapt to the international student experience by adapting a lens of migration? What is the role of cultural capital acquired while abroad in the process of reentry migration? Is the reentry process facilitated by the educational objectives obtained in the U.S? This study examines the lived experience of South Korea and Saudi Arabians as a window into the lives of international students as educational migrants. Acquiring cultural capital - the personal resources and assets an individual uses to negotiate their social environment - abroad is perceived as a way to better navigate the conditions of economic precarity. However, what unfolds is a significant transformative experience in the interstices of liminal spaces abroad that often results into a liminal condition upon reentry migration. The role of cultural capital acquired from the educational migration process has a stronger influence than the actual educational achievements obtained. This research seeks to work towards an anthropology of higher education, bringing the topic of student mobility into an anthropological frame in order to expand scholarship and inform educational curriculum and policy affecting the international student experience. Title: International students as educational migrants : east and southwest Asian perspectives Author: Visconti, Lauren A. Projected to reach one million people next year, international students in the United States are undergoing a transformative educational migration. Moving away from the existing study abroad paradigm is the first step to more accurately understand the lived experience of an educational migrant. Discovering the perceptions of what value an American education holds and accomplishes for students back home is central to revealing the major conditions and influences both propelling educational migration, the experience, and the course, features, and impacts of reentry migration. What prompts students to engage in this risky transformative activity? How can U.S. academic institutions better adapt to the international student experience by adapting a lens of migration? What is the role of cultural capital acquired while abroad in the process of reentry migration? Is the reentry process facilitated by the educational objectives obtained in the U.S? This study examines the lived experience of South Korea and Saudi Arabians as a window into the lives of international students as educational migrants. Acquiring cultural capital - the personal resources and assets an individual uses to negotiate their social environment - abroad is perceived as a way to better navigate the conditions of economic precarity. However, what unfolds is a significant transformative experience in the interstices of liminal spaces abroad that often results into a liminal condition upon reentry migration. The role of cultural capital acquired from the educational migration process has a stronger influence than the actual educational achievements obtained. This research seeks to work towards an anthropology of higher education, bringing the topic of student mobility into an anthropological frame in order to expand scholarship and inform educational curriculum and policy affecting the international student experience. Close

• 45. [Article] A behavior‐oriented dynamic model for sandbar migration and 2DH evolution

  A nonlinear model is developed to study the time‐dependent relationship between the alongshore variability of a sandbar, a(t), and alongshore‐averaged sandbar position, xc(t). Sediment transport equations ...

  Citation × Citation Citation Abstract Copy Title: A behavior‐oriented dynamic model for sandbar migration and 2DH evolution Author: Plant, Nathaniel G., Splinter, Kristen D., Holman, Robert A. A nonlinear model is developed to study the time‐dependent relationship between the alongshore variability of a sandbar, a(t), and alongshore‐averaged sandbar position, xc(t). Sediment transport equations are derived from energetics‐based formulations. A link between this continuous physical representation and a parametric form describing the migration of sandbars of constant shape is established through a simple transformation of variables. The model is driven by offshore wave conditions. The parametric equations are dynamically coupled such that changes in one term (i.e., xc) drive changes in the other (i.e., a(t)). The model is tested on 566 days of data from Palm Beach, New South Wales, Australia. Using weighted nonlinear least squares to estimate best fit model coefficients, the model explained 49% and 41% of the variance in measured xc and a(t), respectively. Comparisons against a 1‐D horizontal (1DH) version of the model showed significant improvements when the 2DH terms were included (1DH and 2DH Brier skill scores were −0.12 and 0.42, respectively). Onshore bar migration was not predicted in the 1DH model, while the 2DH model correctly predicted onshore migration in the presence of 2DH morphology and allowed the bar to remain closer to shore for a given amount of breaking, providing an important hysteresis to the system. The model is consistent with observations that active bar migration occurs under breaking waves with onshore migration occurring at timescales of days to weeks and increasing 2DH morphology, while offshore migration occurs rapidly under high waves and coincides with a reduction in 2DH morphology. Title: A behavior‐oriented dynamic model for sandbar migration and 2DH evolution Author: Plant, Nathaniel G., Splinter, Kristen D., Holman, Robert A. A nonlinear model is developed to study the time‐dependent relationship between the alongshore variability of a sandbar, a(t), and alongshore‐averaged sandbar position, xc(t). Sediment transport equations are derived from energetics‐based formulations. A link between this continuous physical representation and a parametric form describing the migration of sandbars of constant shape is established through a simple transformation of variables. The model is driven by offshore wave conditions. The parametric equations are dynamically coupled such that changes in one term (i.e., xc) drive changes in the other (i.e., a(t)). The model is tested on 566 days of data from Palm Beach, New South Wales, Australia. Using weighted nonlinear least squares to estimate best fit model coefficients, the model explained 49% and 41% of the variance in measured xc and a(t), respectively. Comparisons against a 1‐D horizontal (1DH) version of the model showed significant improvements when the 2DH terms were included (1DH and 2DH Brier skill scores were −0.12 and 0.42, respectively). Onshore bar migration was not predicted in the 1DH model, while the 2DH model correctly predicted onshore migration in the presence of 2DH morphology and allowed the bar to remain closer to shore for a given amount of breaking, providing an important hysteresis to the system. The model is consistent with observations that active bar migration occurs under breaking waves with onshore migration occurring at timescales of days to weeks and increasing 2DH morphology, while offshore migration occurs rapidly under high waves and coincides with a reduction in 2DH morphology. Close

• 46. [Article] Patterns of vertical distribution and migration of zooplankton at Ocean Station “P”

  Stratified bongo net samples taken at depths between 0 and 500 m at Ocean Station “P” in the subarctic Pacific in early July 1971 have been analyzed to determine the vertical structure of the zooplankton ...

  Citation × Citation Citation Abstract Copy Title: Patterns of vertical distribution and migration of zooplankton at Ocean Station “P” Author: Marlowe, Christopher J., Miller, Charles B. Stratified bongo net samples taken at depths between 0 and 500 m at Ocean Station “P” in the subarctic Pacific in early July 1971 have been analyzed to determine the vertical structure of the zooplankton community. Distributions for 99 categories of animals have been grouped by factor analysis into five basic patterns: surface dwellers, a bimodal subsurface pattern, and three patterns of deep-dwelling forms with progressively deeper upper limits. Diurnal vertical migration was restricted to a very small fraction of the species present, primarily those previously described as strong migrators. The upward migration of some of these species stopped in the thermocline between 25 and 100 m. The minimum of biomass density found between 75 and 200 m by earlier workers was confirmed, and a similar minimum was found in the distribution of a number of species. Title: Patterns of vertical distribution and migration of zooplankton at Ocean Station “P” Author: Marlowe, Christopher J., Miller, Charles B. Stratified bongo net samples taken at depths between 0 and 500 m at Ocean Station “P” in the subarctic Pacific in early July 1971 have been analyzed to determine the vertical structure of the zooplankton community. Distributions for 99 categories of animals have been grouped by factor analysis into five basic patterns: surface dwellers, a bimodal subsurface pattern, and three patterns of deep-dwelling forms with progressively deeper upper limits. Diurnal vertical migration was restricted to a very small fraction of the species present, primarily those previously described as strong migrators. The upward migration of some of these species stopped in the thermocline between 25 and 100 m. The minimum of biomass density found between 75 and 200 m by earlier workers was confirmed, and a similar minimum was found in the distribution of a number of species. Close

• 47. [Article] Vertical distribution patterns in a subarctic Pacific zooplankton community

  A study has been made of the vertical distributions and migrations of a large number of zooplankton species at Weather Station "P" in the Subarctic Pacific. Simultaneously towed horizontal opening-closing ...

  Citation × Citation Citation Abstract Copy Title: Vertical distribution patterns in a subarctic Pacific zooplankton community Author: Marlowe, Christopher J. A study has been made of the vertical distributions and migrations of a large number of zooplankton species at Weather Station "P" in the Subarctic Pacific. Simultaneously towed horizontal opening-closing nets were used for the study. The distributions and migrations of 104 taxa have been subjectively grouped into seven basic patterns. A few taxa could not be so grouped. Examination of hydrographic features reveals correlations between animal distributions and strong hydrographic gradients. It is concluded that: 1. In boreal oceanic waters, few animals perform diurnal migrations, 2. Depth ranges for most zooplankton are on the order of hundreds of meters, and 3. Hydrographic features may influence the vertical distributions and migrations of zooplankton. Title: Vertical distribution patterns in a subarctic Pacific zooplankton community Author: Marlowe, Christopher J. A study has been made of the vertical distributions and migrations of a large number of zooplankton species at Weather Station "P" in the Subarctic Pacific. Simultaneously towed horizontal opening-closing nets were used for the study. The distributions and migrations of 104 taxa have been subjectively grouped into seven basic patterns. A few taxa could not be so grouped. Examination of hydrographic features reveals correlations between animal distributions and strong hydrographic gradients. It is concluded that: 1. In boreal oceanic waters, few animals perform diurnal migrations, 2. Depth ranges for most zooplankton are on the order of hundreds of meters, and 3. Hydrographic features may influence the vertical distributions and migrations of zooplankton. Close

• 48. [Article] Latinos en Oregón: Stories of Migration and Settlement in Madras, Oregon

  The Oregon Migrations Symposium was sponsored by Oregon Historical Society, Wayne Morse Center for Law and Politics and the UO Labor Education Research Center. It brought together scholars and holders ...

  Citation × Citation Citation Abstract Copy Title: Latinos en Oregón: Stories of Migration and Settlement in Madras, Oregon Author: Fernández, Natalia The Oregon Migrations Symposium was sponsored by Oregon Historical Society, Wayne Morse Center for Law and Politics and the UO Labor Education Research Center. It brought together scholars and holders of community history to investigate the various ways that Oregon inhabitants and newcomers have shaped each other, helping us better understand today’s discussions about belonging. Title: Latinos en Oregón: Stories of Migration and Settlement in Madras, Oregon Author: Fernández, Natalia The Oregon Migrations Symposium was sponsored by Oregon Historical Society, Wayne Morse Center for Law and Politics and the UO Labor Education Research Center. It brought together scholars and holders of community history to investigate the various ways that Oregon inhabitants and newcomers have shaped each other, helping us better understand today’s discussions about belonging. Close

• 49. [Article] Families on the move : the Powledge family of Meriwether County, Georgia 1820-1900

  The migrations of four generations of the Powledge family centering around Meriwether County, Georgia were described within the context of social and economic forces in the United States in 1820 to 1900. ...

  Citation × Citation Citation Abstract Copy Title: Families on the move : the Powledge family of Meriwether County, Georgia 1820-1900 Author: Roberts, Nancy A. The migrations of four generations of the Powledge family centering around Meriwether County, Georgia were described within the context of social and economic forces in the United States in 1820 to 1900. The family was representative of thousands of families that migrated westward. The migrations were found to correlate with much of the literature on migration and with the economic and social trends in the nineteenth century. Land acquisition as a means to economic improvement and, secondarily, information and support from kin and neighbors were found to be the most important factors in Powledge family movements. Title: Families on the move : the Powledge family of Meriwether County, Georgia 1820-1900 Author: Roberts, Nancy A. The migrations of four generations of the Powledge family centering around Meriwether County, Georgia were described within the context of social and economic forces in the United States in 1820 to 1900. The family was representative of thousands of families that migrated westward. The migrations were found to correlate with much of the literature on migration and with the economic and social trends in the nineteenth century. Land acquisition as a means to economic improvement and, secondarily, information and support from kin and neighbors were found to be the most important factors in Powledge family movements. Close

• 50. [Article] A Pivot Point? Economic Slow-Down Affects Oregon’s Migration Flow

  The combination of three components: fertility, mortality, and migration, collectively lead to population change. Fertility and mortality events in recent history, including escalated fertility levels ...

  Citation × Citation Citation Abstract Copy Title: A Pivot Point? Economic Slow-Down Affects Oregon’s Migration Flow Author: Jurjevich, Jason R. Year: 2011 The combination of three components: fertility, mortality, and migration, collectively lead to population change. Fertility and mortality events in recent history, including escalated fertility levels associated with the ‘baby boom cohort’ and spikes in mortality linked to the Spanish Flu of 1918 for example, have produced demonstrative demographic effects. However, both the unpredictability and ability of migration to produce virtually immediate impacts, often enduring for decades across social, cultural, demographic, and economic landscapes, has long captured the attention of scholars and public policy makers alike. Over the past several decades here in Oregon, migration has undoubtedly shaped the state socially and culturally, but equally pronounced and perhaps more tangible have been the long-term challenges and prospects linked to the reciprocal relationship between migration and economics. Title: A Pivot Point? Economic Slow-Down Affects Oregon’s Migration Flow Author: Jurjevich, Jason R. Year: 2011 The combination of three components: fertility, mortality, and migration, collectively lead to population change. Fertility and mortality events in recent history, including escalated fertility levels associated with the ‘baby boom cohort’ and spikes in mortality linked to the Spanish Flu of 1918 for example, have produced demonstrative demographic effects. However, both the unpredictability and ability of migration to produce virtually immediate impacts, often enduring for decades across social, cultural, demographic, and economic landscapes, has long captured the attention of scholars and public policy makers alike. Over the past several decades here in Oregon, migration has undoubtedly shaped the state socially and culturally, but equally pronounced and perhaps more tangible have been the long-term challenges and prospects linked to the reciprocal relationship between migration and economics. Close