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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

• 11. [Article] Critically endangered western gray whales migrate to the eastern North Pacific

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Author(s) and published by the Royal Society. It can be found at: http://r...

  Citation × Citation Citation Abstract Copy Title: Critically endangered western gray whales migrate to the eastern North Pacific Author: Bradford, Amanda L., Tsidulko, Grigory A., Irvine, Ladd M., Mate, Bruce R., Rozhnov, Vyacheslav V., Vertyankin, Vladimir V., Ilyashenko, Valentin Yu. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Author(s) and published by the Royal Society. It can be found at: http://rsbl.royalsocietypublishing.org/ Title: Critically endangered western gray whales migrate to the eastern North Pacific Author: Bradford, Amanda L., Tsidulko, Grigory A., Irvine, Ladd M., Mate, Bruce R., Rozhnov, Vyacheslav V., Vertyankin, Vladimir V., Ilyashenko, Valentin Yu. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The Author(s) and published by the Royal Society. It can be found at: http://rsbl.royalsocietypublishing.org/ Close

• 12. [Article] Migratory behavior and passage of redband trout (Oncorhynchus mykiss) in the Donner und Blitzen River, Oregon

  Salmonids in arid high-elevation streams find themselves at the fringe of their tolerance range. Under the conditions they endure in such environments, long-distance migratory movements among widely dispersed ...

  Citation × Citation Citation Abstract Copy Title: Migratory behavior and passage of redband trout (Oncorhynchus mykiss) in the Donner und Blitzen River, Oregon Author: Anderson, Matthew C. Salmonids in arid high-elevation streams find themselves at the fringe of their tolerance range. Under the conditions they endure in such environments, long-distance migratory movements among widely dispersed habitats may be an important mechanism for some fish to persist, and even thrive. The Donner und Blitzen (Blitzen) River redband trout (Oncorhynchus mykiss gairdneri) population is known to have a migratory life-history component, but little is known about the timing, spatial patterns, or ecological context of the migration. I tracked trout movements and passage delays at diversion dams with radio telemetry and passive integrated transponder (PIT) tags from March 2007 to November 2008. PIT tag readers established at four locations (river km 1, 35, 48, and 76) recorded large-scale movements of trout. Three of the readers also recorded ladder entry time, ladder ascending time, and total passage time of each trout. My results indicated the existence of a life-history in which redband trout made long-distance migrations both as sub-adults and as adults. While adult trout migrated for reproductive purposes, movement of immature individuals appeared to be a response to seasonal stream temperature conditions. Trout migration rate was positively correlated with fork length and mean river discharge but was not associated with stream temperature, tagging method, or the number of dams passed. The upstream-most detection location for radio-tagged adults that reached potential spawning habitat was not different for trout from the lower river versus the middle river (t(42) = 1.07, p = .29); however, lower river trout reached spawning habitats an average of 20 days later (t(42) = 3.78, p < .001). Passage times at the dams were not affected by discharge, fork length, or tagging method. At a jump-pool ladder trout were 7.23 times more likely to pass during day than at night (2(1, N = 40) = 9.96, p = .002). At a Denil ladder, trout were 25.6% more likely to pass with each degree Celsius increase in stream temperature (2(1, N = 22) = 4.39, p = .036). At all three dams, a greater proportion of the total passage time involved trout finding and entering the ladder than ascending the ladder after initial entry. Trout passage times varied significantly between each of the dams. This study highlights the importance of landscape-scale distribution of habitats and refugia in determining life-history and movement patterns of trout. Migratory behavior was related to both life-stage and environmental conditions. Maintaining connectivity with efficient passage throughout the river is a critical element in managing migratory fish populations like the one in this study. The well-functioning fish ladders were those that provided adequate fish attraction, while those ladders with poor attraction delayed migrating trout for long periods. Title: Migratory behavior and passage of redband trout (Oncorhynchus mykiss) in the Donner und Blitzen River, Oregon Author: Anderson, Matthew C. Salmonids in arid high-elevation streams find themselves at the fringe of their tolerance range. Under the conditions they endure in such environments, long-distance migratory movements among widely dispersed habitats may be an important mechanism for some fish to persist, and even thrive. The Donner und Blitzen (Blitzen) River redband trout (Oncorhynchus mykiss gairdneri) population is known to have a migratory life-history component, but little is known about the timing, spatial patterns, or ecological context of the migration. I tracked trout movements and passage delays at diversion dams with radio telemetry and passive integrated transponder (PIT) tags from March 2007 to November 2008. PIT tag readers established at four locations (river km 1, 35, 48, and 76) recorded large-scale movements of trout. Three of the readers also recorded ladder entry time, ladder ascending time, and total passage time of each trout. My results indicated the existence of a life-history in which redband trout made long-distance migrations both as sub-adults and as adults. While adult trout migrated for reproductive purposes, movement of immature individuals appeared to be a response to seasonal stream temperature conditions. Trout migration rate was positively correlated with fork length and mean river discharge but was not associated with stream temperature, tagging method, or the number of dams passed. The upstream-most detection location for radio-tagged adults that reached potential spawning habitat was not different for trout from the lower river versus the middle river (t(42) = 1.07, p = .29); however, lower river trout reached spawning habitats an average of 20 days later (t(42) = 3.78, p < .001). Passage times at the dams were not affected by discharge, fork length, or tagging method. At a jump-pool ladder trout were 7.23 times more likely to pass during day than at night (2(1, N = 40) = 9.96, p = .002). At a Denil ladder, trout were 25.6% more likely to pass with each degree Celsius increase in stream temperature (2(1, N = 22) = 4.39, p = .036). At all three dams, a greater proportion of the total passage time involved trout finding and entering the ladder than ascending the ladder after initial entry. Trout passage times varied significantly between each of the dams. This study highlights the importance of landscape-scale distribution of habitats and refugia in determining life-history and movement patterns of trout. Migratory behavior was related to both life-stage and environmental conditions. Maintaining connectivity with efficient passage throughout the river is a critical element in managing migratory fish populations like the one in this study. The well-functioning fish ladders were those that provided adequate fish attraction, while those ladders with poor attraction delayed migrating trout for long periods. Close

• 13. [Article] Lakeview Newcomers: Mexican and Caucasian Perspectives

  Citation × Citation Citation Abstract Copy Title: Lakeview Newcomers: Mexican and Caucasian Perspectives Author: Johnson, Carly Title: Lakeview Newcomers: Mexican and Caucasian Perspectives Author: Johnson, Carly Close

• 14. [Article] IrvineLaddHMSCCriticallyEndangeredWesternGrayWhales.pdf

  Citation × Citation Citation Abstract Copy Title: IrvineLaddHMSCCriticallyEndangeredWesternGrayWhales.pdf Author: Vertyankin, Vladimir V., Tsidulko, Grigory A., Irvine, Ladd M., Ilyashenko, Valentin Yu., Rozhnov, Vyacheslav V., Bradford, Amanda L., Mate, Bruce R. Title: IrvineLaddHMSCCriticallyEndangeredWesternGrayWhales.pdf Author: Vertyankin, Vladimir V., Tsidulko, Grigory A., Irvine, Ladd M., Ilyashenko, Valentin Yu., Rozhnov, Vyacheslav V., Bradford, Amanda L., Mate, Bruce R. Close

• 15. [Article] Foraging ecology, diving behavior, and migration patterns of harbor seals (Phoca vitulina richardii) from a glacial fjord in Alaska in relation to prey availability and oceanographic features

  Understanding the movement behavior and foraging strategies of individuals across multiple spatial and temporal scales is essential not only for understanding the biological requirements of individuals ...

  Citation × Citation Citation Abstract Copy Title: Foraging ecology, diving behavior, and migration patterns of harbor seals (Phoca vitulina richardii) from a glacial fjord in Alaska in relation to prey availability and oceanographic features Author: Womble, Jamie Neil Understanding the movement behavior and foraging strategies of individuals across multiple spatial and temporal scales is essential not only for understanding the biological requirements of individuals but also for linking individual strategies to population level effects. Glacial fjords scattered throughout south-central and southeastern Alaska host some of the largest seasonal aggregations of harbor seals (Phoca vitulina richardii) in the world, and an estimated 15% of the harbor seal population in Alaska is found seasonally at these glacial ice sites. Over the last two decades, the number of harbor seals has declined at two of the primary glacial fjords, in Aialik Bay in south-central Alaska and in Glacier Bay in southeastern Alaska, thus raising concerns regarding the viability of seal populations in glacial fjord environments. From 2004-2009, the foraging ecology, diving behavior, and migration patterns of harbor seals from Glacier Bay National Park, Alaska were examined in relation to prey availability and oceanographic features in Glacier Bay and the surrounding regions of southeastern Alaska. Time-depth recorders, very high frequency transmitters, and satellite-linked transmitters were used to quantify the vertical and horizontal movement patterns of harbor seals in the marine environment. Specifically, (1) I characterized the diving behavior, foraging areas, and foraging strategies of female harbor seals from terrestrial and glacial ice sites relative to prey availability during the breeding season (May-June) in Glacier Bay, (2) I quantified the intra-population variation in at-sea post-breeding season (September-April) distribution and movement patterns of female harbor seals in relation to oceanographic features, (3) I quantified the post-breeding season migration patterns of female harbor seals relative to the boundaries of the marine protected area of Glacier Bay National Park, and (4) I characterized the use of the continental shelf region of the eastern Gulf of Alaska by female harbor seals from Glacier Bay, both as a foraging area and as a migratory corridor in relation to oceanographic features. During the breeding season, there was a substantial degree of intra-population variation in the diving behavior and foraging areas of juvenile and adult female seals from glacial ice and terrestrial sites in Glacier Bay. The presence of multiple diving strategies suggests that differences in the relative density and depth of prey fields in glacial ice and terrestrial habitats in addition to seal age and reproductive status may influence diving and foraging behavior of harbor seals. During the post-breeding season, juvenile and adult female harbor seals ranged extensively beyond the boundaries of the marine protected area of Glacier Bay National Park, throughout the northern inshore waters of southeastern Alaska and the continental shelf region of the eastern Gulf of Alaska between Cross Sound and Prince William Sound, Alaska (up to 900 kilometers away). Seals exhibited a relatively high degree of intra-population variation in their at-sea post-breeding season distribution patterns that may be a function of extrinsic factors such as oceanographic characteristics, which can influence prey availability as well as intrinsic factors including previous experience with foraging areas and seal condition and age. Use of the continental shelf region of the eastern Gulf of Alaska by harbor seals as a foraging area may be due to enhanced biological productivity which may be associated with ephemeral hydrographic and/or static bathymetric features. Despite extensive migrations of seals from Glacier Bay during the post-breeding season, there was a high degree of inter-annual site fidelity of seals to Glacier Bay the following breeding season after seals were captured. Title: Foraging ecology, diving behavior, and migration patterns of harbor seals (Phoca vitulina richardii) from a glacial fjord in Alaska in relation to prey availability and oceanographic features Author: Womble, Jamie Neil Understanding the movement behavior and foraging strategies of individuals across multiple spatial and temporal scales is essential not only for understanding the biological requirements of individuals but also for linking individual strategies to population level effects. Glacial fjords scattered throughout south-central and southeastern Alaska host some of the largest seasonal aggregations of harbor seals (Phoca vitulina richardii) in the world, and an estimated 15% of the harbor seal population in Alaska is found seasonally at these glacial ice sites. Over the last two decades, the number of harbor seals has declined at two of the primary glacial fjords, in Aialik Bay in south-central Alaska and in Glacier Bay in southeastern Alaska, thus raising concerns regarding the viability of seal populations in glacial fjord environments. From 2004-2009, the foraging ecology, diving behavior, and migration patterns of harbor seals from Glacier Bay National Park, Alaska were examined in relation to prey availability and oceanographic features in Glacier Bay and the surrounding regions of southeastern Alaska. Time-depth recorders, very high frequency transmitters, and satellite-linked transmitters were used to quantify the vertical and horizontal movement patterns of harbor seals in the marine environment. Specifically, (1) I characterized the diving behavior, foraging areas, and foraging strategies of female harbor seals from terrestrial and glacial ice sites relative to prey availability during the breeding season (May-June) in Glacier Bay, (2) I quantified the intra-population variation in at-sea post-breeding season (September-April) distribution and movement patterns of female harbor seals in relation to oceanographic features, (3) I quantified the post-breeding season migration patterns of female harbor seals relative to the boundaries of the marine protected area of Glacier Bay National Park, and (4) I characterized the use of the continental shelf region of the eastern Gulf of Alaska by female harbor seals from Glacier Bay, both as a foraging area and as a migratory corridor in relation to oceanographic features. During the breeding season, there was a substantial degree of intra-population variation in the diving behavior and foraging areas of juvenile and adult female seals from glacial ice and terrestrial sites in Glacier Bay. The presence of multiple diving strategies suggests that differences in the relative density and depth of prey fields in glacial ice and terrestrial habitats in addition to seal age and reproductive status may influence diving and foraging behavior of harbor seals. During the post-breeding season, juvenile and adult female harbor seals ranged extensively beyond the boundaries of the marine protected area of Glacier Bay National Park, throughout the northern inshore waters of southeastern Alaska and the continental shelf region of the eastern Gulf of Alaska between Cross Sound and Prince William Sound, Alaska (up to 900 kilometers away). Seals exhibited a relatively high degree of intra-population variation in their at-sea post-breeding season distribution patterns that may be a function of extrinsic factors such as oceanographic characteristics, which can influence prey availability as well as intrinsic factors including previous experience with foraging areas and seal condition and age. Use of the continental shelf region of the eastern Gulf of Alaska by harbor seals as a foraging area may be due to enhanced biological productivity which may be associated with ephemeral hydrographic and/or static bathymetric features. Despite extensive migrations of seals from Glacier Bay during the post-breeding season, there was a high degree of inter-annual site fidelity of seals to Glacier Bay the following breeding season after seals were captured. Close

• 16. [Article] IrvineLaddHMSCCriticallyEndangeredWesternGrayWhalesFigure1.jpg

  Citation × Citation Citation Abstract Copy Title: IrvineLaddHMSCCriticallyEndangeredWesternGrayWhalesFigure1.jpg Author: Bradford, Amanda L., Tsidulko, Grigory A., Irvine, Ladd M., Mate, Bruce R., Rozhnov, Vyacheslav V., Vertyankin, Vladimir V., Ilyashenko, Valentin Yu. Title: IrvineLaddHMSCCriticallyEndangeredWesternGrayWhalesFigure1.jpg Author: Bradford, Amanda L., Tsidulko, Grigory A., Irvine, Ladd M., Mate, Bruce R., Rozhnov, Vyacheslav V., Vertyankin, Vladimir V., Ilyashenko, Valentin Yu. Close

• 17. [Article] Juvenile coho salmon movement and migration through tide gates

  Tidal marshlands in the upper estuary ecotone provide essential habitat for juvenile salmonids. In this environment, salmonids grow rapidly and acclimate to saltwater. Worldwide, tidal marshes have been ...

  Citation × Citation Citation Abstract Copy Title: Juvenile coho salmon movement and migration through tide gates Author: Bass, Arthur Langer Tidal marshlands in the upper estuary ecotone provide essential habitat for juvenile salmonids. In this environment, salmonids grow rapidly and acclimate to saltwater. Worldwide, tidal marshes have been diked and drained to provide agricultural and residential land. Tide gates are one-way doors integrated into dike systems that prevent saltwater flooding and allow upland drainage to the estuary during low tide. By preventing tidal exchange, tide gates have significant upstream effects on water temperature and chemistry, plant and animal community structure, and geomorphology. Since they are closed most of the day and may be difficult to pass when open, tide gates may act as fish passage barriers for juvenile salmonids. They may also affect juvenile salmon migration timing by altering environmental variables that influence emigration rate in upstream habitats. We conducted our research in Coos Bay, one of the many Oregon estuaries with extensive use of tide gates. We studied three streams, one with a top-hinged tide gate, one with a side-hinged gate, and one without any tide gates that acted as our reference site. Our study species was coho salmon, Oncorhynchus kisutch, which may encounter tide gates both in the subyearling and smolt life stages in our study streams. Our objectives were to: 1) quantify upstream and downstream fish passage occurrence at all three sites, 2) determine whether juvenile coho salmon passage is associated with a specific range of gate conditions, and 3) identify any associations between coho smolt emigration rate and environmental variables that are influenced by tide gates. We installed stationary passive integrated transponder (PIT) antennae around both tide gates and a tidal channel in the non-gated stream to record the movement of PIT tagged juvenile coho salmon. Coho salmon smolts passed upstream most frequently at the non-gated channel (48% of all smolts detected at the array), next the side-hinged gate (28%), and lastly, the top-hinged gate (3%). Juvenile coho salmon passed more frequently at a specific range of gate angles and tailwater depths at both top hinged and side-hinged tide gates. Smolts passed downstream more frequently at greater gate angles and tailwater depths than available on average at both tide gates. Subyearlings passed upstream more frequently during small gate angles and a narrow range of tailwater depths at the top-hinged gate but did not pass more frequently under a particular range of conditions at the side-hinged gate. At the top-hinged gate, conditions favorable for subyearling upstream passage occurred towards the end of the gate open period and therefore subyearlings were severely limited in their opportunities for passage. At multiple sites, emigration rate was associated with environmental variables that may be altered by tide gates. Increases in water temperature were associated with an increasing likelihood of smolt emigration at multiple sites. At a tide gate that allowed upstream estuarine influence, increasing salinity was associated with a decreasing likelihood of emigration. Our results suggest that tide gates may interfere with salmonid movement and migration by creating physical barriers to fish passage and potentially influencing migratory timing by altering environmental variables. When installing or retrofitting tide gates, these factors should be taken into consideration since a tide gate's design may determine the severity of its effects on salmonids. Our work should be considered a case study and the findings should not be assumed to be transferable due to the great diversity of tide gate installations in use. We recommend further research, including a more in depth analysis of the affects of tide gates on subyearling coho salmon and an investigation of piscivorous predator exploitation of tide gates. Title: Juvenile coho salmon movement and migration through tide gates Author: Bass, Arthur Langer Tidal marshlands in the upper estuary ecotone provide essential habitat for juvenile salmonids. In this environment, salmonids grow rapidly and acclimate to saltwater. Worldwide, tidal marshes have been diked and drained to provide agricultural and residential land. Tide gates are one-way doors integrated into dike systems that prevent saltwater flooding and allow upland drainage to the estuary during low tide. By preventing tidal exchange, tide gates have significant upstream effects on water temperature and chemistry, plant and animal community structure, and geomorphology. Since they are closed most of the day and may be difficult to pass when open, tide gates may act as fish passage barriers for juvenile salmonids. They may also affect juvenile salmon migration timing by altering environmental variables that influence emigration rate in upstream habitats. We conducted our research in Coos Bay, one of the many Oregon estuaries with extensive use of tide gates. We studied three streams, one with a top-hinged tide gate, one with a side-hinged gate, and one without any tide gates that acted as our reference site. Our study species was coho salmon, Oncorhynchus kisutch, which may encounter tide gates both in the subyearling and smolt life stages in our study streams. Our objectives were to: 1) quantify upstream and downstream fish passage occurrence at all three sites, 2) determine whether juvenile coho salmon passage is associated with a specific range of gate conditions, and 3) identify any associations between coho smolt emigration rate and environmental variables that are influenced by tide gates. We installed stationary passive integrated transponder (PIT) antennae around both tide gates and a tidal channel in the non-gated stream to record the movement of PIT tagged juvenile coho salmon. Coho salmon smolts passed upstream most frequently at the non-gated channel (48% of all smolts detected at the array), next the side-hinged gate (28%), and lastly, the top-hinged gate (3%). Juvenile coho salmon passed more frequently at a specific range of gate angles and tailwater depths at both top hinged and side-hinged tide gates. Smolts passed downstream more frequently at greater gate angles and tailwater depths than available on average at both tide gates. Subyearlings passed upstream more frequently during small gate angles and a narrow range of tailwater depths at the top-hinged gate but did not pass more frequently under a particular range of conditions at the side-hinged gate. At the top-hinged gate, conditions favorable for subyearling upstream passage occurred towards the end of the gate open period and therefore subyearlings were severely limited in their opportunities for passage. At multiple sites, emigration rate was associated with environmental variables that may be altered by tide gates. Increases in water temperature were associated with an increasing likelihood of smolt emigration at multiple sites. At a tide gate that allowed upstream estuarine influence, increasing salinity was associated with a decreasing likelihood of emigration. Our results suggest that tide gates may interfere with salmonid movement and migration by creating physical barriers to fish passage and potentially influencing migratory timing by altering environmental variables. When installing or retrofitting tide gates, these factors should be taken into consideration since a tide gate's design may determine the severity of its effects on salmonids. Our work should be considered a case study and the findings should not be assumed to be transferable due to the great diversity of tide gate installations in use. We recommend further research, including a more in depth analysis of the affects of tide gates on subyearling coho salmon and an investigation of piscivorous predator exploitation of tide gates. Close

• 18. [Article] Differential gene expression between fall- and spring-run Chinook salmon assessed by long serial analysis of gene expression

  Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been ...

  Citation × Citation Citation Abstract Copy Title: Differential gene expression between fall- and spring-run Chinook salmon assessed by long serial analysis of gene expression Author: Banks, Michael A., McArthur, Andrew G., Birkeland, Shanda R., Bernier, Jeremiah C., Cipriano, Michael J. Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been well described. Current methods, such as long serial analysis of gene expression (LongSAGE) and microarrays, allow gene expression to be analyzed for thousands of genes simultaneously. To investigate whether differential gene expression is observed between fall- and spring-run Chinook salmon from California's Central Valley, LongSAGE libraries were constructed. Three libraries containing between 25,512 and 29,372 sequenced tags (21 base pairs/tag) were generated using messenger RNA from the brains of adult Chinook salmon returning in fall and spring and from one ocean-caught Chinook salmon. Tags were annotated to genes using complementary DNA libraries from Atlantic salmon Salmo salar and rainbow trout O. mykiss. Differentially expressed genes, as estimated by differences in the number of sequence tags, were found in all pairwise comparisons of libraries (freshwater versus saltwater = 40 genes; fall versus spring = 11 genes; and spawning versus nonspawning = 51 genes). The gene for ependymin, an extracellular glycoprotein involved in behavioral plasticity in fish, exhibited the most differential expression among the three groupings. Reverse transcription polymerase chain reaction analysis verified the differential expression of ependymin between the fall- and spring-run samples. These LongSAGE libraries, the first reported for Chinook salmon, provide a window of the transcriptional changes during Chinook salmon return migration to freshwater and spawning and increase the amount of expressed sequence data. Title: Differential gene expression between fall- and spring-run Chinook salmon assessed by long serial analysis of gene expression Author: Banks, Michael A., McArthur, Andrew G., Birkeland, Shanda R., Bernier, Jeremiah C., Cipriano, Michael J. Of all Pacific salmonids, Chinook salmon Oncorhynchus tshawytscha display the greatest variability in return times to freshwater. The molecular mechanisms of these differential return times have not been well described. Current methods, such as long serial analysis of gene expression (LongSAGE) and microarrays, allow gene expression to be analyzed for thousands of genes simultaneously. To investigate whether differential gene expression is observed between fall- and spring-run Chinook salmon from California's Central Valley, LongSAGE libraries were constructed. Three libraries containing between 25,512 and 29,372 sequenced tags (21 base pairs/tag) were generated using messenger RNA from the brains of adult Chinook salmon returning in fall and spring and from one ocean-caught Chinook salmon. Tags were annotated to genes using complementary DNA libraries from Atlantic salmon Salmo salar and rainbow trout O. mykiss. Differentially expressed genes, as estimated by differences in the number of sequence tags, were found in all pairwise comparisons of libraries (freshwater versus saltwater = 40 genes; fall versus spring = 11 genes; and spawning versus nonspawning = 51 genes). The gene for ependymin, an extracellular glycoprotein involved in behavioral plasticity in fish, exhibited the most differential expression among the three groupings. Reverse transcription polymerase chain reaction analysis verified the differential expression of ependymin between the fall- and spring-run samples. These LongSAGE libraries, the first reported for Chinook salmon, provide a window of the transcriptional changes during Chinook salmon return migration to freshwater and spawning and increase the amount of expressed sequence data. Close

• 19. [Article] A topography of dams in China : impacts to agriculture, labor, and migration

  Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, ...

  Citation × Citation Citation Abstract Copy Title: A topography of dams in China : impacts to agriculture, labor, and migration Author: Foster-Moore, Eric Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, remains contentious due to the potential for negative environmental and socioeconomic impacts. Despite numerous case studies, there is little systematic empirical evidence about either the contribution of dams to human development or their negative impacts to humans and the environment. Identifying the impact of dams also presents a methodological challenge because dam placement is likely endogenous to socioeconomic outcomes. The topographic suitability of a landscape for dam construction provides a source of exogenous variation in dam siting, which, building on the work of previous scholars, I exploit to identify the effect of large dams on agriculture, population change, and labor allocation. My results suggest that dams have decreased grain production in the counties where they were built and have drawn labor into non-agricultural fields. Dams appear to impact population subgroups in predictable ways and create identifiable winners and losers. Title: A topography of dams in China : impacts to agriculture, labor, and migration Author: Foster-Moore, Eric Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, remains contentious due to the potential for negative environmental and socioeconomic impacts. Despite numerous case studies, there is little systematic empirical evidence about either the contribution of dams to human development or their negative impacts to humans and the environment. Identifying the impact of dams also presents a methodological challenge because dam placement is likely endogenous to socioeconomic outcomes. The topographic suitability of a landscape for dam construction provides a source of exogenous variation in dam siting, which, building on the work of previous scholars, I exploit to identify the effect of large dams on agriculture, population change, and labor allocation. My results suggest that dams have decreased grain production in the counties where they were built and have drawn labor into non-agricultural fields. Dams appear to impact population subgroups in predictable ways and create identifiable winners and losers. Close

• 20. [Article] Copper, chromium, and arsenic levels in soils surrounding posts treated with chromated copper arsenate (CCA)

  The levels of copper, chromium, and arsenic in soil surrounding CCA-treated posts and beneath CCA-treated stakes were investigated at a plot near Gainesville, Florida. Metal levels were elevated in soil ...

  Citation × Citation Citation Abstract Copy Title: Copper, chromium, and arsenic levels in soils surrounding posts treated with chromated copper arsenate (CCA) Author: Morrell, Jeffrey J., Huffman, Jacob The levels of copper, chromium, and arsenic in soil surrounding CCA-treated posts and beneath CCA-treated stakes were investigated at a plot near Gainesville, Florida. Metal levels were elevated in soil immediately adjacent to the treated wood, but decreased with distance away or depth. Mean extractable arsenic levels ranged from 1.74 to 8.19 ppm immediately adjacent to the posts, but declined to less than 1 ppm in samples 150 and 300 mm away, regardless of depth sampled. The results suggest that soil contamination due to the presence of CCA-treated wood for 45 years is minimal. Title: Copper, chromium, and arsenic levels in soils surrounding posts treated with chromated copper arsenate (CCA) Author: Morrell, Jeffrey J., Huffman, Jacob The levels of copper, chromium, and arsenic in soil surrounding CCA-treated posts and beneath CCA-treated stakes were investigated at a plot near Gainesville, Florida. Metal levels were elevated in soil immediately adjacent to the treated wood, but decreased with distance away or depth. Mean extractable arsenic levels ranged from 1.74 to 8.19 ppm immediately adjacent to the posts, but declined to less than 1 ppm in samples 150 and 300 mm away, regardless of depth sampled. The results suggest that soil contamination due to the presence of CCA-treated wood for 45 years is minimal. Close