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• 31. [Article] Coordinated Population Forecast for Jackson County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2015-2065

  Different growth patterns occur in different parts of the county and these local trends within the UGBs and the area outside UGBs collectively influence population growth rates for the county as a whole. Jackson ...

  Citation × Citation Citation Abstract Copy Title: Coordinated Population Forecast for Jackson County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2015-2065 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Gorecki, Carson, Tetrick, David Year: 2015 Different growth patterns occur in different parts of the county and these local trends within the UGBs and the area outside UGBs collectively influence population growth rates for the county as a whole. Jackson County’s total population has grown steadily since 2000, with an average annual growth rate of above one percent between 2000 and 2010 (Figure 1); however some of its sub-areas experienced more rapid population growth during the 2000s. Eagle Point and Central Point UGBs posted the highest average annual growth rates at 5.6 and 2.9 percent, respectively, during the 2000 to 2010 period. Jackson County’s positive population growth in the 2000s was the result of substantial net in-migration and natural increase. Meanwhile an aging population not only led to an increase in deaths, but also resulted in a smaller proportion of women in their childbearing years. This along with more women choosing to have fewer children and have them at older ages has led to slower growth in births. The more rapid growth in deaths relative to that of births caused natural increase—the difference between births and deaths—to decline to almost nothing by 2014. While net in-migration outweighed declining natural increase during the early and middle years of the last decade, the gap between these two numbers shrank during the later years—slowing population growth by 2010. Since 2010 net in-migration has driven rising population growth rates, while natural increase continues to shrink. Total population in Jackson County as a whole as well as within its sub-areas will likely grow at a slightly faster pace in the first 20 years of the forecast period (2015 to 2035), relative to the last 30 years (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to lead to natural decrease (more deaths than births). As natural decrease occurs, population growth will become increasingly reliant on net in-migration. Even so, Jackson County’s total population is forecast to increase by nearly 44,600 over the next 20 years (2015-2035) and by nearly 95,600 over the entire 50-year forecast period (2015-2065). Sub-areas that showed strong population growth in the 2000s are expected to experience similar rates of population growth during the forecast period. Title: Coordinated Population Forecast for Jackson County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2015-2065 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Gorecki, Carson, Tetrick, David Year: 2015 Different growth patterns occur in different parts of the county and these local trends within the UGBs and the area outside UGBs collectively influence population growth rates for the county as a whole. Jackson County’s total population has grown steadily since 2000, with an average annual growth rate of above one percent between 2000 and 2010 (Figure 1); however some of its sub-areas experienced more rapid population growth during the 2000s. Eagle Point and Central Point UGBs posted the highest average annual growth rates at 5.6 and 2.9 percent, respectively, during the 2000 to 2010 period. Jackson County’s positive population growth in the 2000s was the result of substantial net in-migration and natural increase. Meanwhile an aging population not only led to an increase in deaths, but also resulted in a smaller proportion of women in their childbearing years. This along with more women choosing to have fewer children and have them at older ages has led to slower growth in births. The more rapid growth in deaths relative to that of births caused natural increase—the difference between births and deaths—to decline to almost nothing by 2014. While net in-migration outweighed declining natural increase during the early and middle years of the last decade, the gap between these two numbers shrank during the later years—slowing population growth by 2010. Since 2010 net in-migration has driven rising population growth rates, while natural increase continues to shrink. Total population in Jackson County as a whole as well as within its sub-areas will likely grow at a slightly faster pace in the first 20 years of the forecast period (2015 to 2035), relative to the last 30 years (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to lead to natural decrease (more deaths than births). As natural decrease occurs, population growth will become increasingly reliant on net in-migration. Even so, Jackson County’s total population is forecast to increase by nearly 44,600 over the next 20 years (2015-2035) and by nearly 95,600 over the entire 50-year forecast period (2015-2065). Sub-areas that showed strong population growth in the 2000s are expected to experience similar rates of population growth during the forecast period. Close

• 32. [Article] Coordinated Population Forecast for Union County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066

  Union County’s total population has grown slowly since 2000, with an average annual growth rate of half percent between 2000 and 2010 (Figure 1). However, some of its sub-areas experienced more rapid population ...

  Citation × Citation Citation Abstract Copy Title: Coordinated Population Forecast for Union County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Tetrick, David, Michel, Julia Year: 2016 Union County’s total population has grown slowly since 2000, with an average annual growth rate of half percent between 2000 and 2010 (Figure 1). However, some of its sub-areas experienced more rapid population growth during the 2000s. Summerville posted the highest average annual growth rate of 1.4 percent, and Imbler and Union were close behind with average annual growth rates of about 1.2 percent each. Union County’s positive population growth in the 2000s was the combined result of a consistent natural increase and a net in-migration. The larger number of births relative to deaths has led to a natural increase (more births than deaths) in every year from 2000 to 2015 (Figure 12). While net in-migration fluctuated dramatically during the early years of the last decade, the number of in-migrants has been slightly more stable during recent years, accounting for the majority of Union County’s population increase. Total population in Union County as a whole as well as within some of its sub-areas will likely grow at a slightly faster pace in the nearer-term (2016 to 2035) compared to the longer-term (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to contribute to natural decrease (more deaths than births). As natural decrease occurs, population growth will become increasingly reliant on net in-migration. Steady increase in net in-migration is expected to offset the growing natural decrease, leading to relatively steady population growth over the forecast period. However, an aging population is expected to not only lead to an increase in deaths, but a smaller proportion of women in their childbearing years will likely result in a long-term stabilization in the number of births. Title: Coordinated Population Forecast for Union County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Tetrick, David, Michel, Julia Year: 2016 Union County’s total population has grown slowly since 2000, with an average annual growth rate of half percent between 2000 and 2010 (Figure 1). However, some of its sub-areas experienced more rapid population growth during the 2000s. Summerville posted the highest average annual growth rate of 1.4 percent, and Imbler and Union were close behind with average annual growth rates of about 1.2 percent each. Union County’s positive population growth in the 2000s was the combined result of a consistent natural increase and a net in-migration. The larger number of births relative to deaths has led to a natural increase (more births than deaths) in every year from 2000 to 2015 (Figure 12). While net in-migration fluctuated dramatically during the early years of the last decade, the number of in-migrants has been slightly more stable during recent years, accounting for the majority of Union County’s population increase. Total population in Union County as a whole as well as within some of its sub-areas will likely grow at a slightly faster pace in the nearer-term (2016 to 2035) compared to the longer-term (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to contribute to natural decrease (more deaths than births). As natural decrease occurs, population growth will become increasingly reliant on net in-migration. Steady increase in net in-migration is expected to offset the growing natural decrease, leading to relatively steady population growth over the forecast period. However, an aging population is expected to not only lead to an increase in deaths, but a smaller proportion of women in their childbearing years will likely result in a long-term stabilization in the number of births. Close

• 33. [Article] Coordinated Population Forecast for Sherman County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066

  Sherman County’s total population has declined since 2000, at an average annual rate of nearly one percent between 2000 and 2010 (Figure 1); however, Wasco UGB, one of its sub-areas, experienced population ...

  Citation × Citation Citation Abstract Copy Title: Coordinated Population Forecast for Sherman County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Tetrick, David, Michel, Julia Year: 2016 Sherman County’s total population has declined since 2000, at an average annual rate of nearly one percent between 2000 and 2010 (Figure 1); however, Wasco UGB, one of its sub-areas, experienced population growth during the 2000s. Wasco, the most populous UGB, posted an average annual growth rate of a little less than one percent during the 2000 to 2010 period. This translated into a population increase of about 30 persons. Sherman County’s population decline in the 2000s was the direct result of consistent net out-migration and periods of natural decreases (more deaths than births, Figure 12). The county’s aging population has contributed to an increase in deaths, which combined with a relatively steady number of births has resulted in a natural decrease for nine out of the 15 years between 2000 and 2015. While net out-migration and natural decrease were common during the last decade, in more recent years (2010 to 2015) net in-migration has occurred, bringing with it some population growth. Total population in Sherman County is forecast to increase in the near-term (2016 to 2035), a trend that is driven by growth in the two sub-areas of Rufus and Wasco (Figure 1); however population decline is expected for the county over the remaining 31 years of the forecast period. This population decrease is the result of a growing natural decrease, which is expected to exceed net in-migration around 2030. Sherman County’s total population is forecast to increase by about 50 persons over the next 19 years (2016-2035), but will likely see population decline of more than 80 persons during the last 31 years of the forecast period (2035-2066). Sub-areas are expected to generally follow their historical patterns of population increase or decrease over the forecast period. Title: Coordinated Population Forecast for Sherman County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Tetrick, David, Michel, Julia Year: 2016 Sherman County’s total population has declined since 2000, at an average annual rate of nearly one percent between 2000 and 2010 (Figure 1); however, Wasco UGB, one of its sub-areas, experienced population growth during the 2000s. Wasco, the most populous UGB, posted an average annual growth rate of a little less than one percent during the 2000 to 2010 period. This translated into a population increase of about 30 persons. Sherman County’s population decline in the 2000s was the direct result of consistent net out-migration and periods of natural decreases (more deaths than births, Figure 12). The county’s aging population has contributed to an increase in deaths, which combined with a relatively steady number of births has resulted in a natural decrease for nine out of the 15 years between 2000 and 2015. While net out-migration and natural decrease were common during the last decade, in more recent years (2010 to 2015) net in-migration has occurred, bringing with it some population growth. Total population in Sherman County is forecast to increase in the near-term (2016 to 2035), a trend that is driven by growth in the two sub-areas of Rufus and Wasco (Figure 1); however population decline is expected for the county over the remaining 31 years of the forecast period. This population decrease is the result of a growing natural decrease, which is expected to exceed net in-migration around 2030. Sherman County’s total population is forecast to increase by about 50 persons over the next 19 years (2016-2035), but will likely see population decline of more than 80 persons during the last 31 years of the forecast period (2035-2066). Sub-areas are expected to generally follow their historical patterns of population increase or decrease over the forecast period. Close

• 34. [Article] Coordinated Population Forecast for Hood River County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066

  Hood River County’s total population has grown steadily since 2000, with an average annual growth rate of about one percent between 2000 and 2010 (Figure 1). The Hood River UGB experienced more rapid population ...

  Citation × Citation Citation Abstract Copy Title: Coordinated Population Forecast for Hood River County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Tetrick, David, Michel, Julia Year: 2016 Hood River County’s total population has grown steadily since 2000, with an average annual growth rate of about one percent between 2000 and 2010 (Figure 1). The Hood River UGB experienced more rapid population growth during the 2000s, averaging more than one percent per year during the 2000 to 2010 period. Hood River County’s positive population growth in the 2000s was the result of a steady natural increase and periods of substantial net in-migration (Figure 12). The larger number of births relative to deaths has led to a natural increase (more births than deaths) in every year from 2000 to 2015. While net in-migration fluctuated dramatically during the early and middle years of the last decade, the number of in-migrants has increased stably during recent years, contributing to a population increase. Overall, Hood River County’s population growth is becoming more reliant on net in-migration. Total population in Hood River County as a whole as well as within its sub-areas will likely grow at a slightly faster pace in the near-term (2016 to 2035) compared to the long-term (Figure 1). The tapering of growth rates is driven by a growing natural decrease, as well as a larger population base. As natural decrease occurs over the final 31-year period, population growth will become increasingly reliant on net in-migration. Even so, Hood River County’s total population is forecast to increase by more than 6,000 during the initial 19-year period (2016-2035) and by more than 14,000 over the entire 50-year forecast (2016-2066). Sub-areas that showed strong population growth in the 2000s are expected to experience similar rates of population growth during the forecast period. Title: Coordinated Population Forecast for Hood River County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2016-2066 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Tetrick, David, Michel, Julia Year: 2016 Hood River County’s total population has grown steadily since 2000, with an average annual growth rate of about one percent between 2000 and 2010 (Figure 1). The Hood River UGB experienced more rapid population growth during the 2000s, averaging more than one percent per year during the 2000 to 2010 period. Hood River County’s positive population growth in the 2000s was the result of a steady natural increase and periods of substantial net in-migration (Figure 12). The larger number of births relative to deaths has led to a natural increase (more births than deaths) in every year from 2000 to 2015. While net in-migration fluctuated dramatically during the early and middle years of the last decade, the number of in-migrants has increased stably during recent years, contributing to a population increase. Overall, Hood River County’s population growth is becoming more reliant on net in-migration. Total population in Hood River County as a whole as well as within its sub-areas will likely grow at a slightly faster pace in the near-term (2016 to 2035) compared to the long-term (Figure 1). The tapering of growth rates is driven by a growing natural decrease, as well as a larger population base. As natural decrease occurs over the final 31-year period, population growth will become increasingly reliant on net in-migration. Even so, Hood River County’s total population is forecast to increase by more than 6,000 during the initial 19-year period (2016-2035) and by more than 14,000 over the entire 50-year forecast (2016-2066). Sub-areas that showed strong population growth in the 2000s are expected to experience similar rates of population growth during the forecast period. Close

• 35. [Article] Beyond the Fringe

  Reviews the book: Lincoln Bramwell. Wilderburbs: Communities on Nature’s Edge. Seattle: University of Washington Press, 2014. Andrew Needham. Power Lines: Phoenix and the Making of the Modern Southwest. ...

  Citation × Citation Citation Abstract Copy Title: Beyond the Fringe Author: Abbott, Carl Year: 2016 Reviews the book: Lincoln Bramwell. Wilderburbs: Communities on Nature’s Edge. Seattle: University of Washington Press, 2014. Andrew Needham. Power Lines: Phoenix and the Making of the Modern Southwest. Princeton, N.J.: Princeton University Press, 2014. Title: Beyond the Fringe Author: Abbott, Carl Year: 2016 Reviews the book: Lincoln Bramwell. Wilderburbs: Communities on Nature’s Edge. Seattle: University of Washington Press, 2014. Andrew Needham. Power Lines: Phoenix and the Making of the Modern Southwest. Princeton, N.J.: Princeton University Press, 2014. Close

• 36. [Article] Melting in the Mantle Wedge: Quantifying the Effects of Crustal Morphology and Viscous Decoupling on Melt Production with Application to the Cascadia Subduction Zone

  Arc magmatism is sustained by the complex interactions between the subducting slab, the overriding plate, and the mantle wedge. Partial melting of mantle peridotite is achieved by fluid-induced flux melting ...

  Citation × Citation Citation Abstract Copy Title: Melting in the Mantle Wedge: Quantifying the Effects of Crustal Morphology and Viscous Decoupling on Melt Production with Application to the Cascadia Subduction Zone Author: Yang, Jiaming Year: 2017 Arc magmatism is sustained by the complex interactions between the subducting slab, the overriding plate, and the mantle wedge. Partial melting of mantle peridotite is achieved by fluid-induced flux melting and decompression melting due to upward flow. The distribution of melting is sensitive to temperature, the pattern of flow, and the pressure in the mantle wedge. The arc front is the surface manifestation of partial melting in the mantle wedge and is characterized by a narrow chain of active volcanoes that migrate in time. The conventional interpretation is that changes in slab dip angle lead to changes in the arc front position relative to the trench. We explore an alternative hypothesis: evolution of the overlying plate, specifically thickening of the arc root, causes arc front migration. We investigate the effects of varying crustal morphology and viscous decoupling of the shallow slab-mantle interface on melt production using 2D numerical models involving a stationary overriding plate, a subducting plate with prescribed motion, and a dynamic mantle wedge. Melt production is quantified using a hydrous melting parameterization. We conclude: 1) Localized lithospheric thickening shifts the locus of melt production trenchward while thinning shifts melting landward. 2) Inclined LAB topography modulates the asthenospheric flow field, producing a narrow, well-defined arc front. 3) Thickening of the overriding plate exerts increased torque on the slab, favoring shallowing of the dip angle. 4) Viscous decoupling produces a cold, stagnant forearc mantle but promotes arc front melting due to reduction in the radius of corner flow, leading to higher temperatures at the coupling/decoupling transition. Title: Melting in the Mantle Wedge: Quantifying the Effects of Crustal Morphology and Viscous Decoupling on Melt Production with Application to the Cascadia Subduction Zone Author: Yang, Jiaming Year: 2017 Arc magmatism is sustained by the complex interactions between the subducting slab, the overriding plate, and the mantle wedge. Partial melting of mantle peridotite is achieved by fluid-induced flux melting and decompression melting due to upward flow. The distribution of melting is sensitive to temperature, the pattern of flow, and the pressure in the mantle wedge. The arc front is the surface manifestation of partial melting in the mantle wedge and is characterized by a narrow chain of active volcanoes that migrate in time. The conventional interpretation is that changes in slab dip angle lead to changes in the arc front position relative to the trench. We explore an alternative hypothesis: evolution of the overlying plate, specifically thickening of the arc root, causes arc front migration. We investigate the effects of varying crustal morphology and viscous decoupling of the shallow slab-mantle interface on melt production using 2D numerical models involving a stationary overriding plate, a subducting plate with prescribed motion, and a dynamic mantle wedge. Melt production is quantified using a hydrous melting parameterization. We conclude: 1) Localized lithospheric thickening shifts the locus of melt production trenchward while thinning shifts melting landward. 2) Inclined LAB topography modulates the asthenospheric flow field, producing a narrow, well-defined arc front. 3) Thickening of the overriding plate exerts increased torque on the slab, favoring shallowing of the dip angle. 4) Viscous decoupling produces a cold, stagnant forearc mantle but promotes arc front melting due to reduction in the radius of corner flow, leading to higher temperatures at the coupling/decoupling transition. Close

• 37. [Article] Papers Please: Immigration, Enforcement, and Remittances

  Immigrants are an understated agent in local economies. Whilst legal immigrants may be accounted for in the macro realm, illegal immigrants are very much an externality. Immigrant agents participate heavily ...

  Citation × Citation Citation Abstract Copy Title: Papers Please: Immigration, Enforcement, and Remittances Author: Rojas-Fallas, Jose A. Year: 2017 Immigrants are an understated agent in local economies. Whilst legal immigrants may be accounted for in the macro realm, illegal immigrants are very much an externality. Immigrant agents participate heavily in local economies, almost exclusively, due to their status and the implicit risks associated with it. Immigrants’ decision to migrate towards better economies come with the goal of achieving prosperity that more than likely would not have been possible in their location of origin. A majority of immigrants are heads of households that migrate alone seeking greater wages to support their household. They do this through remittances. These are capital accumulation packages that are sent through institutions (formal or informal) to their households and communities. In the presence of anti-immigration rhetoric and laws of this nature being created, the immigrant agent will see a change in economic activity. With certainty being removed, behavior goes through unintended changes. Immigrants that are in a position of danger, and a necessity to remit to their household back in their community of origin, will do so. One way or the other. If institutional mistrust sets in, there are economic consequences from the lack of use of institutions, that will spillover in to the macro-environment. Authors: Jose A. Rojas-Fallas, Jamein P. Cunningham Presenter: Jose A. Rojas-Fallas Title: Papers Please: Immigration, Enforcement, and Remittances Author: Rojas-Fallas, Jose A. Year: 2017 Immigrants are an understated agent in local economies. Whilst legal immigrants may be accounted for in the macro realm, illegal immigrants are very much an externality. Immigrant agents participate heavily in local economies, almost exclusively, due to their status and the implicit risks associated with it. Immigrants’ decision to migrate towards better economies come with the goal of achieving prosperity that more than likely would not have been possible in their location of origin. A majority of immigrants are heads of households that migrate alone seeking greater wages to support their household. They do this through remittances. These are capital accumulation packages that are sent through institutions (formal or informal) to their households and communities. In the presence of anti-immigration rhetoric and laws of this nature being created, the immigrant agent will see a change in economic activity. With certainty being removed, behavior goes through unintended changes. Immigrants that are in a position of danger, and a necessity to remit to their household back in their community of origin, will do so. One way or the other. If institutional mistrust sets in, there are economic consequences from the lack of use of institutions, that will spillover in to the macro-environment. Authors: Jose A. Rojas-Fallas, Jamein P. Cunningham Presenter: Jose A. Rojas-Fallas Close

• 38. [Article] Destination Portland: Post-Great Recession Migration Trends in the Rose City Region

  This report explores how individuals decide to move to Portland, why they stay and how the region’s growth challenges might introduce costs that disproportionately burden people of color and young people ...

  Citation × Citation Citation Abstract Copy Title: Destination Portland: Post-Great Recession Migration Trends in the Rose City Region Author: Jurjevich, Jason R., Schrock, Greg, Kang, Jihye Year: 2017 This report explores how individuals decide to move to Portland, why they stay and how the region’s growth challenges might introduce costs that disproportionately burden people of color and young people of lower socioeconomic status. Title: Destination Portland: Post-Great Recession Migration Trends in the Rose City Region Author: Jurjevich, Jason R., Schrock, Greg, Kang, Jihye Year: 2017 This report explores how individuals decide to move to Portland, why they stay and how the region’s growth challenges might introduce costs that disproportionately burden people of color and young people of lower socioeconomic status. Close

• 39. [Article] Neurobiology of Seasonal Life-history Transitions

  Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such ...

  Citation × Citation Citation Abstract Copy Title: Neurobiology of Seasonal Life-history Transitions Author: Lucas, Ashley Rae Year: 2015 Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors. Title: Neurobiology of Seasonal Life-history Transitions Author: Lucas, Ashley Rae Year: 2015 Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected male and female snakes in different migratory stages during the spring and fall. Brains were processed for AVT and NPY immunohistochemistry and the total number of immunoreactive (-ir) cells quantified for each individual. As predicted, males had significantly more AVT-ir cells in the preoptic area and bed nucleus of the stria terminalis, brain regions important for courtship behavior, during the spring mating season compared to the fall. Females had significantly more AVT-ir cells in the preoptic area during the spring compared to the fall and, surprisingly, did not exhibit seasonal changes in NPY. In contrast, males had significantly more NPY-ir cells in the cortex, a region important for spatial memory, and in the posterior hypothalamus during the fall compared to the spring, which likely reflects increased feeding behavior during the summer foraging period. Neither AVT- nor NPY-ir cell number varied significantly with migratory status, indicating that seasonal changes in these neuropeptides are not directly related to migration. I then asked if the observed seasonal changes in AVT and NPY in males and females are related to the transition from reproductive to non-reproductive states. Compared to courting males, non-courting males had significantly more AVT-ir cells in the supraoptic nucleus and more NPY-ir cells in the cortex. AVT- and NPY-ir cells did not differ between unmated and mated females. Collectively, my results suggest that AVT and NPY play a role in regulating seasonal transitions in male reproductive behavior, rather than regulating migration per se. Further, these data indicate that both AVT and NPY are regulating reproductive behavior differently in males versus females. These data provide the framework for future studies examining the mechanisms regulating transitions between reproductive, migratory and foraging behaviors. Close

• 40. [Article] Coordinated Population Forecast for Josephine County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2015-2065

  Different growth patterns occur in different parts of the county and these local trends within the UGBs and the area outside UGBs collectively influence population growth rates for the county as a whole. Josephine ...

  Citation × Citation Citation Abstract Copy Title: Coordinated Population Forecast for Josephine County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2015-2065 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Gorecki, Carson, Tetrick, David Year: 2015 Different growth patterns occur in different parts of the county and these local trends within the UGBs and the area outside UGBs collectively influence population growth rates for the county as a whole. Josephine County’s total population as a whole has grown slowly since 2000; with an average annual growth rate of less than one percent between 2000 and 2010 (Figure 1); however some of its sub-areas experienced more rapid population growth during the 2000s. Grants Pass and Cave Junction posted average annual growth rates at 2.1 and 1.6 percent, respectively, during the 2000 to 2010 period. Josephine County’s positive population growth in the 2000s was the result of substantial net inmigration. Meanwhile an aging population not only led to an increase in deaths, but also resulted in a smaller proportion of women in their childbearing years. This along with more women choosing to have fewer children and have them at older ages has led to slow growth in the number of births. The growing number of deaths and shrinking number of births led to natural decrease—more deaths than births—in every year from 2000 to 2014. While net in-migration outweighed natural decrease during the early and middle years of the last decade, the gap between these two numbers shrank during the later years— bringing population decline in 2012. Since 2012 net in-migration has increased, driving population increase for 2013 and 2014. Total population in Josephine County as a whole as well as within its sub-areas will likely grow at a slightly faster pace in the first 20 years of the forecast period (2015 to 2035) relative to the last 30 years (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to lead to natural decrease (more deaths than births). As natural decrease occurs over time population growth is expected to become increasingly reliant on net in-migration. Even so, Josephine County’s total population is forecast to increase by more than 16,000 over the next 20 years (2015-2035) and by nearly 38,000 over the entire 50-year forecast period (2015-2065). Subareas that showed strong population growth in the 2000s are expected to experience similar rates of population growth during the forecast period. Title: Coordinated Population Forecast for Josephine County, its Urban Growth Boundaries (UGB), and Area Outside UGBs 2015-2065 Author: Portland State University. Population Research Center, Ruan, Xiaomin, Proehl, Risa, Jurjevich, Jason R., Rancik, Kevin, Kessi, Janai, Gorecki, Carson, Tetrick, David Year: 2015 Different growth patterns occur in different parts of the county and these local trends within the UGBs and the area outside UGBs collectively influence population growth rates for the county as a whole. Josephine County’s total population as a whole has grown slowly since 2000; with an average annual growth rate of less than one percent between 2000 and 2010 (Figure 1); however some of its sub-areas experienced more rapid population growth during the 2000s. Grants Pass and Cave Junction posted average annual growth rates at 2.1 and 1.6 percent, respectively, during the 2000 to 2010 period. Josephine County’s positive population growth in the 2000s was the result of substantial net inmigration. Meanwhile an aging population not only led to an increase in deaths, but also resulted in a smaller proportion of women in their childbearing years. This along with more women choosing to have fewer children and have them at older ages has led to slow growth in the number of births. The growing number of deaths and shrinking number of births led to natural decrease—more deaths than births—in every year from 2000 to 2014. While net in-migration outweighed natural decrease during the early and middle years of the last decade, the gap between these two numbers shrank during the later years— bringing population decline in 2012. Since 2012 net in-migration has increased, driving population increase for 2013 and 2014. Total population in Josephine County as a whole as well as within its sub-areas will likely grow at a slightly faster pace in the first 20 years of the forecast period (2015 to 2035) relative to the last 30 years (Figure 1). The tapering of growth rates is largely driven by an aging population—a demographic trend which is expected to lead to natural decrease (more deaths than births). As natural decrease occurs over time population growth is expected to become increasingly reliant on net in-migration. Even so, Josephine County’s total population is forecast to increase by more than 16,000 over the next 20 years (2015-2035) and by nearly 38,000 over the entire 50-year forecast period (2015-2065). Subareas that showed strong population growth in the 2000s are expected to experience similar rates of population growth during the forecast period. Close