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• 1. [Article] The economics of forest-dependent regions

  This dissertation explores two economic phenomena involving forest-dependent areas: wage distribution and migration pattern of individuals. Are forest-dependent rural areas less desirable for workers from ...

  Citation × Citation Citation Abstract Copy Title: The economics of forest-dependent regions Author: Biswas, Smita This dissertation explores two economic phenomena involving forest-dependent areas: wage distribution and migration pattern of individuals. Are forest-dependent rural areas less desirable for workers from the standpoint of labor market returns? Are different skills (e.g. education, experience) rewarded differently in these areas? If there are interregional wage differences, would that influence a working-age individual's migration decision and residential location choice? These questions are examined here with data from Public Use Microdata Survey (PUMS) of the United States 2000 decennial census. I focus my inquiry on the socio-economic characteristics of forest and non forest-dependent areas, the interregional difference in labor market outcomes, and the influence of wage differential and other factors on the migration decisions and residential location choice of working-age individuals. Reduced form log wage equations are estimated for individuals, which incorporate explanatory variables related to both skill factors (such as years of schooling and potential experience) and to non-skill factors (such as minority status) potentially influencing wage. Variations in the interregional wage distribution resulting from differences in skill mix of workers are removed by using a standardized skill distribution. The results indicate that average wages and variation in wage distribution are lower in the forest-dependent areas than other areas. For migration analysis, a Partially Degenerate Nested Logit (PDNL) model is used to model migration decisions and location choice of individuals in the Northwest between 1995 and 2000. Migration decision is modelled as a two stage process: first an individual decides whether to move or stay in his/her original location. Conditional on migration, the individual next chooses his/her destination location from a set of alternative areas. Empirical results indicate that educational attainment and labor market outcomes influence individual's migration decision. Conditional on moving, non-forest dependent areas are more attractive to individuals as residential destinations. Title: The economics of forest-dependent regions Author: Biswas, Smita This dissertation explores two economic phenomena involving forest-dependent areas: wage distribution and migration pattern of individuals. Are forest-dependent rural areas less desirable for workers from the standpoint of labor market returns? Are different skills (e.g. education, experience) rewarded differently in these areas? If there are interregional wage differences, would that influence a working-age individual's migration decision and residential location choice? These questions are examined here with data from Public Use Microdata Survey (PUMS) of the United States 2000 decennial census. I focus my inquiry on the socio-economic characteristics of forest and non forest-dependent areas, the interregional difference in labor market outcomes, and the influence of wage differential and other factors on the migration decisions and residential location choice of working-age individuals. Reduced form log wage equations are estimated for individuals, which incorporate explanatory variables related to both skill factors (such as years of schooling and potential experience) and to non-skill factors (such as minority status) potentially influencing wage. Variations in the interregional wage distribution resulting from differences in skill mix of workers are removed by using a standardized skill distribution. The results indicate that average wages and variation in wage distribution are lower in the forest-dependent areas than other areas. For migration analysis, a Partially Degenerate Nested Logit (PDNL) model is used to model migration decisions and location choice of individuals in the Northwest between 1995 and 2000. Migration decision is modelled as a two stage process: first an individual decides whether to move or stay in his/her original location. Conditional on migration, the individual next chooses his/her destination location from a set of alternative areas. Empirical results indicate that educational attainment and labor market outcomes influence individual's migration decision. Conditional on moving, non-forest dependent areas are more attractive to individuals as residential destinations. Close

• 2. [Article] Extreme Weather Events and Rural-Urban Migration

  In numerous regions around the globe, climate change can be expected to change the pattern of severe weather events. Migration flows have been systematically larger the higher the proportion of the population ...

  Citation × Citation Citation Abstract Copy Title: Extreme Weather Events and Rural-Urban Migration Author: Saif, Raisa Year: 2012 In numerous regions around the globe, climate change can be expected to change the pattern of severe weather events. Migration flows have been systematically larger the higher the proportion of the population in urban areas in the destination county relative to the origin county. Richer models demonstrate that the effects of a number of different types of extreme weather events (i.e. flooding, heat waves, and wildfires) in the origin county on county-to-county migration flows are statistically significantly greater when the destination county is more urbanized. The effect of the number of fatalities from flooding and heat waves in the origin county on migration flows is also amplified when the destination county is more urbanized. Thus it appears that even in a developed country like the U.S. extreme weather events still exacerbate rural-to-urban migration flows. Title: Extreme Weather Events and Rural-Urban Migration Author: Saif, Raisa Year: 2012 In numerous regions around the globe, climate change can be expected to change the pattern of severe weather events. Migration flows have been systematically larger the higher the proportion of the population in urban areas in the destination county relative to the origin county. Richer models demonstrate that the effects of a number of different types of extreme weather events (i.e. flooding, heat waves, and wildfires) in the origin county on county-to-county migration flows are statistically significantly greater when the destination county is more urbanized. The effect of the number of fatalities from flooding and heat waves in the origin county on migration flows is also amplified when the destination county is more urbanized. Thus it appears that even in a developed country like the U.S. extreme weather events still exacerbate rural-to-urban migration flows. Close

• 3. [Article] Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska

  Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater ...

  Citation × Citation Citation Abstract Copy Title: Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska Author: Neilson, Brian J. Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater and marine habitats including lacustrine, riverine, estuarine, and marine. Forty-five whitefish were tagged with radio transmitters in 2006 and 2007, and another 29 whitefish were tagged with acoustic tags in 2008. In addition, otolith chemistry was used to evaluate marine habitat use of humpback whitefish sampled from McKinley Lake in the Copper River Delta, Alaska. Movements and migration of tagged fish were tracked using biotelemetry techniques from boats, airplanes, and fixed receiver stations throughout the spring, summer, and fall. Sagittal otoliths were extracted from 20 humpback whitefish and a chemical analysis was performed to evaluate levels of Sr:Ca. Biotelemetry and sampling results revealed seasonal migrations where humpback whitefish migrated into McKinley Lake in mid to late spring and left the lake by late summer and early fall. Fish migrated to the Copper River in the fall by traveling down Alaganik Slough and then to the Copper River by traveling through Pete Dahl Cutoff Slough or the Gulf of Alaska. Fish travel up the Copper River presumably to their spawning grounds. Nine tagged fish returned to McKinley Lake in 2007 and four tagged fish in 2008, indicating some fidelity to the summer feeding site. Otolith chemistry detected marine migrations in 45% of the samples. Three migratory behaviors were observed, while some individuals inhabited only freshwater environments, some individuals made single migrations to marine habitats, and other individuals made multiple migrations to marine habitats. Age of whitefish ranged from 2 to 9 years. Analysis of small-scale movement of humpback whitefish in McKinley Lake found movement rates to be significantly higher at dusk compared to night in one sampling period. However, diel movement activity in all other diel periods did not significantly differ, suggesting arrhythmic diel movement. A large portion of the lake was occupied at any given time, but not all areas were used equally. Activity levels, measured by change in zones, were variable between dates and indicated that fish often moved between detection zones. An increase in activity was observed in individuals 48 h prior to migration from the lake. This study provides the first documentation of migration, movement, and habitat use of humpback whitefish in the Copper River Delta, Alaska. Results of this study will help inform management of humpback whitefish in order to sustain populations into the future. This information should be considered in land use and species management planning in the Copper River basin including fish passage and harvest regulations. Title: Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska Author: Neilson, Brian J. Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater and marine habitats including lacustrine, riverine, estuarine, and marine. Forty-five whitefish were tagged with radio transmitters in 2006 and 2007, and another 29 whitefish were tagged with acoustic tags in 2008. In addition, otolith chemistry was used to evaluate marine habitat use of humpback whitefish sampled from McKinley Lake in the Copper River Delta, Alaska. Movements and migration of tagged fish were tracked using biotelemetry techniques from boats, airplanes, and fixed receiver stations throughout the spring, summer, and fall. Sagittal otoliths were extracted from 20 humpback whitefish and a chemical analysis was performed to evaluate levels of Sr:Ca. Biotelemetry and sampling results revealed seasonal migrations where humpback whitefish migrated into McKinley Lake in mid to late spring and left the lake by late summer and early fall. Fish migrated to the Copper River in the fall by traveling down Alaganik Slough and then to the Copper River by traveling through Pete Dahl Cutoff Slough or the Gulf of Alaska. Fish travel up the Copper River presumably to their spawning grounds. Nine tagged fish returned to McKinley Lake in 2007 and four tagged fish in 2008, indicating some fidelity to the summer feeding site. Otolith chemistry detected marine migrations in 45% of the samples. Three migratory behaviors were observed, while some individuals inhabited only freshwater environments, some individuals made single migrations to marine habitats, and other individuals made multiple migrations to marine habitats. Age of whitefish ranged from 2 to 9 years. Analysis of small-scale movement of humpback whitefish in McKinley Lake found movement rates to be significantly higher at dusk compared to night in one sampling period. However, diel movement activity in all other diel periods did not significantly differ, suggesting arrhythmic diel movement. A large portion of the lake was occupied at any given time, but not all areas were used equally. Activity levels, measured by change in zones, were variable between dates and indicated that fish often moved between detection zones. An increase in activity was observed in individuals 48 h prior to migration from the lake. This study provides the first documentation of migration, movement, and habitat use of humpback whitefish in the Copper River Delta, Alaska. Results of this study will help inform management of humpback whitefish in order to sustain populations into the future. This information should be considered in land use and species management planning in the Copper River basin including fish passage and harvest regulations. Close

• 4. [Article] Source of cobalt-60 and migrations of albacore off the west coast of north America

  Citation × Citation Citation Abstract Copy Title: Source of cobalt-60 and migrations of albacore off the west coast of north America Author: Pearcy, William G., Krygier, Earl E. Title: Source of cobalt-60 and migrations of albacore off the west coast of north America Author: Pearcy, William G., Krygier, Earl E. Close

• 5. [Article] Latino Immigrant Students: Exploring the Relationship between Migration Experience and Education Outcomes

  The purpose of this study was to contribute to the literature on the educational outcomes and protective factors (i.e., support systems) in the lives of Latino immigrant youth, with a special emphasis ...

  Citation × Citation Citation Abstract Copy Title: Latino Immigrant Students: Exploring the Relationship between Migration Experience and Education Outcomes Author: Ramos, Karina Year: 2015 The purpose of this study was to contribute to the literature on the educational outcomes and protective factors (i.e., support systems) in the lives of Latino immigrant youth, with a special emphasis on how these experiences relate to and are impacted by their migration experiences. Using the cultural-ecological theoretical framework and the Stages of Migration framework, this study utilized an existing data set to explore the relationships between migration stress, psychological distress, experiences of discrimination, and awareness of discrimination in relation to educational outcomes in a sample of 281 Latino immigrant youth. These relationships were then examined to see if they differed as a function of perceived support, gender, and school type (i.e., middle school versus high school). Structural equation modeling was utilized to test the hypothesized model that included migration stress, psychological distress, and education outcomes. The structural model showed very good fit. Results suggest that migration stress has a significant direct effect on psychological distress and on educational outcomes among Latino immigrant youth. Participants reporting high migration stress reported greater psychological distress and had poorer educational outcomes with respect to academic grades, educational aspirations, and educational expectations. Moderation testing indicated the structural model did not vary as a function of perceived support, gender, or school. Implications for research and practice are discussed. Title: Latino Immigrant Students: Exploring the Relationship between Migration Experience and Education Outcomes Author: Ramos, Karina Year: 2015 The purpose of this study was to contribute to the literature on the educational outcomes and protective factors (i.e., support systems) in the lives of Latino immigrant youth, with a special emphasis on how these experiences relate to and are impacted by their migration experiences. Using the cultural-ecological theoretical framework and the Stages of Migration framework, this study utilized an existing data set to explore the relationships between migration stress, psychological distress, experiences of discrimination, and awareness of discrimination in relation to educational outcomes in a sample of 281 Latino immigrant youth. These relationships were then examined to see if they differed as a function of perceived support, gender, and school type (i.e., middle school versus high school). Structural equation modeling was utilized to test the hypothesized model that included migration stress, psychological distress, and education outcomes. The structural model showed very good fit. Results suggest that migration stress has a significant direct effect on psychological distress and on educational outcomes among Latino immigrant youth. Participants reporting high migration stress reported greater psychological distress and had poorer educational outcomes with respect to academic grades, educational aspirations, and educational expectations. Moderation testing indicated the structural model did not vary as a function of perceived support, gender, or school. Implications for research and practice are discussed. Close

• 6. [Article] Aspirational Migration: The Case of Chinese Birth Tourism in the U.S.

  The ways in which individuals navigate the globe today complicates previous conceptualizations of migration and mobility. Once such mode of contemporary movement which challenges scholars is known as "birth ...

  Citation × Citation Citation Abstract Copy Title: Aspirational Migration: The Case of Chinese Birth Tourism in the U.S. Author: Folse, Brandon Year: 2017 The ways in which individuals navigate the globe today complicates previous conceptualizations of migration and mobility. Once such mode of contemporary movement which challenges scholars is known as "birth tourism." This research considers birth tourism to be a form of "lifestyle migration," which I label aspirational migration. By analyzing the motivations which drive many parents to give birth abroad, I shed light on the complex and risky process, which involves a host of players, including family, friends, and a global birth tourism infrastructure. Through this drawn-out process, which begins well before the decision to give birth abroad and continues into the distant future, I argue that birth tourists and their foreign-born children become aspirational migrants and acquire cosmopolitan capital. Title: Aspirational Migration: The Case of Chinese Birth Tourism in the U.S. Author: Folse, Brandon Year: 2017 The ways in which individuals navigate the globe today complicates previous conceptualizations of migration and mobility. Once such mode of contemporary movement which challenges scholars is known as "birth tourism." This research considers birth tourism to be a form of "lifestyle migration," which I label aspirational migration. By analyzing the motivations which drive many parents to give birth abroad, I shed light on the complex and risky process, which involves a host of players, including family, friends, and a global birth tourism infrastructure. Through this drawn-out process, which begins well before the decision to give birth abroad and continues into the distant future, I argue that birth tourists and their foreign-born children become aspirational migrants and acquire cosmopolitan capital. Close

• 7. [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

• 8. [Article] Spawning migration of Perch, Perca fluviatilis (L.), in different coastal waters in the Baltic Sea

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Spawning migration of Perch, Perca fluviatilis (L.), in different coastal waters in the Baltic Sea Author: Siddika, Mahruba, Lehtonen, Hannu Research Paper Title: Spawning migration of Perch, Perca fluviatilis (L.), in different coastal waters in the Baltic Sea Author: Siddika, Mahruba, Lehtonen, Hannu Research Paper Close

• 9. [Article] Main-d'oeuvre et migrations côtières au Mexique

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Main-d'oeuvre et migrations côtières au Mexique Author: Fraga, Julia Research Paper Title: Main-d'oeuvre et migrations côtières au Mexique Author: Fraga, Julia Research Paper Close

• 10. [Article] Effects of estuarine circulation patterns and stress on the migratory behavior of juvenile salmonids (Oncorhynchus sp.)

  For the first objective of this thesis, we attempt to understand the role of water flow and directionality in determining steelhead (Oncorhynchus mykiss) and spring/summer and fall Chinook (O. tschawytscha) ...

  Citation × Citation Citation Abstract Copy Title: Effects of estuarine circulation patterns and stress on the migratory behavior of juvenile salmonids (Oncorhynchus sp.) Author: Truelove, Nathan Kobun For the first objective of this thesis, we attempt to understand the role of water flow and directionality in determining steelhead (Oncorhynchus mykiss) and spring/summer and fall Chinook (O. tschawytscha) migration patterns within the Columbia River Estuary and plume by integrating recent advances in biotelemetry and environmental observation and forecasting systems (EOFS). The underlying methodology included analysis of the spatial and temporal movements of juvenile outmigrant salmonids with hydrological data from the CORIE modeling system (http://www.ccalmr.ogi.edu/CORIE). The CORIE modeling system, an EOFS for the Columbia River and nearshore environment, integrates a real-time sensor network, data management system and advanced 3-dimensional numerical models. Numerical simulations of key physical variables (water level, velocities, and directionality) were generated for the precise time and location that individual juvenile salmonids implanted with radio transmitters were present in the Columbia River Estuary. Five general behavioral trends were evident from these simulations: i) passive movement (drifting) during ebb tides, ii) active swimming with the current during ebb tides, iii) active swimming against the current during flood tides, iv) active swimming cross current during flood tides, and v) passive drifting during flood tide. Direction of water flow had a significant effect on fish velocity. All fish types showed a positive relationship between fish velocity and simulated drifter velocity with outgoing water flow. During slack water flow (< 0.25 m/s), this relationship was only observed in barged fall Chinook. With incoming water flow, spring/summer and fall Chinook fish types showed no relationship, whereas steelhead did. Analysis over a three-year period suggested that data from the CORIE modeling system corresponded well with juvenile salmonid migratory behavior and that the model may be a useful tool for evaluating the impact of different hydrological regimes on fish movement. The secondary objective of this thesis evaluated the effects of both acute and chronic crowding stressors on the migratory behavior of hatchery reared juvenile steelhead released into Abernathy Creek, a tributary of the Columbia River Estuary, Washington. The acute stress treatment consisted of surgical implantation of a NanoTag radio transmitter (Lotek Wireless, Canada), followed by 6 hours of crowding immediately prior to release. The chronic stress treatment consisted of surgical implantation of a PIT-tag (Digital Angel Corporation), 36 days of acclimation, followed by 3 weeks of crowding in low water conditions prior to release. Short-term migratory success of steelhead that received the acute stress treatment was determined by radio telemetry. Numbers of migrating fish that received experimental stress treatments and their speed was determined by both mobile radio telemetry and stationary PIT-tag and radio-tag interrogation systems already established on Abernathy Creek. Acute and chronic stress treatments both significantly delayed migration by 2 to 10 days, respectively, compared to controls. Furthermore, the acute stress treatment significantly decreased the both the rate of migration and numbers of juvenile steelhead that successfully migrated out of Abernathy creek. Title: Effects of estuarine circulation patterns and stress on the migratory behavior of juvenile salmonids (Oncorhynchus sp.) Author: Truelove, Nathan Kobun For the first objective of this thesis, we attempt to understand the role of water flow and directionality in determining steelhead (Oncorhynchus mykiss) and spring/summer and fall Chinook (O. tschawytscha) migration patterns within the Columbia River Estuary and plume by integrating recent advances in biotelemetry and environmental observation and forecasting systems (EOFS). The underlying methodology included analysis of the spatial and temporal movements of juvenile outmigrant salmonids with hydrological data from the CORIE modeling system (http://www.ccalmr.ogi.edu/CORIE). The CORIE modeling system, an EOFS for the Columbia River and nearshore environment, integrates a real-time sensor network, data management system and advanced 3-dimensional numerical models. Numerical simulations of key physical variables (water level, velocities, and directionality) were generated for the precise time and location that individual juvenile salmonids implanted with radio transmitters were present in the Columbia River Estuary. Five general behavioral trends were evident from these simulations: i) passive movement (drifting) during ebb tides, ii) active swimming with the current during ebb tides, iii) active swimming against the current during flood tides, iv) active swimming cross current during flood tides, and v) passive drifting during flood tide. Direction of water flow had a significant effect on fish velocity. All fish types showed a positive relationship between fish velocity and simulated drifter velocity with outgoing water flow. During slack water flow (< 0.25 m/s), this relationship was only observed in barged fall Chinook. With incoming water flow, spring/summer and fall Chinook fish types showed no relationship, whereas steelhead did. Analysis over a three-year period suggested that data from the CORIE modeling system corresponded well with juvenile salmonid migratory behavior and that the model may be a useful tool for evaluating the impact of different hydrological regimes on fish movement. The secondary objective of this thesis evaluated the effects of both acute and chronic crowding stressors on the migratory behavior of hatchery reared juvenile steelhead released into Abernathy Creek, a tributary of the Columbia River Estuary, Washington. The acute stress treatment consisted of surgical implantation of a NanoTag radio transmitter (Lotek Wireless, Canada), followed by 6 hours of crowding immediately prior to release. The chronic stress treatment consisted of surgical implantation of a PIT-tag (Digital Angel Corporation), 36 days of acclimation, followed by 3 weeks of crowding in low water conditions prior to release. Short-term migratory success of steelhead that received the acute stress treatment was determined by radio telemetry. Numbers of migrating fish that received experimental stress treatments and their speed was determined by both mobile radio telemetry and stationary PIT-tag and radio-tag interrogation systems already established on Abernathy Creek. Acute and chronic stress treatments both significantly delayed migration by 2 to 10 days, respectively, compared to controls. Furthermore, the acute stress treatment significantly decreased the both the rate of migration and numbers of juvenile steelhead that successfully migrated out of Abernathy creek. Close