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• 41. [Article] The influence of sex, migration distance, and latitude on expression of anadromy in Oncorhynchus mykiss

  The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation ...

  Citation × Citation Citation Abstract Copy Title: The influence of sex, migration distance, and latitude on expression of anadromy in Oncorhynchus mykiss Author: Ohms, Haley The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation of partially migratory species. In particular, why individuals adopt a particular phenotype has been the focus of numerous research efforts. In the partially migratory species Oncorhynchys mykiss (commonly known as steelhead and rainbow trout), I found that sex plays a strong role in whether an individual adopts an anadromous or resident life history. I observed a higher frequency of females adopting the anadromous tactic throughout the species range, and I attributed this to the relationship between body size and reproductive success in females that is not present in males. I did not observe differences in female bias along gradients of latitude or migration distance, and I hypothesize that while the frequency of tactics among populations may change along these gradients, either the change is equal between males and females, or an interaction of latitude and migration distance may control changes. I did not observe a corresponding male bias in the one resident population I sampled, and suggest that this is the result of a high frequency of residents in that population. I propose that sex ratios could be a valuable metric for measuring frequency of life-history tactics in populations and could facilitate the investigation into the controls of life-history tactics across broad scales. Title: The influence of sex, migration distance, and latitude on expression of anadromy in Oncorhynchus mykiss Author: Ohms, Haley The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation of partially migratory species. In particular, why individuals adopt a particular phenotype has been the focus of numerous research efforts. In the partially migratory species Oncorhynchys mykiss (commonly known as steelhead and rainbow trout), I found that sex plays a strong role in whether an individual adopts an anadromous or resident life history. I observed a higher frequency of females adopting the anadromous tactic throughout the species range, and I attributed this to the relationship between body size and reproductive success in females that is not present in males. I did not observe differences in female bias along gradients of latitude or migration distance, and I hypothesize that while the frequency of tactics among populations may change along these gradients, either the change is equal between males and females, or an interaction of latitude and migration distance may control changes. I did not observe a corresponding male bias in the one resident population I sampled, and suggest that this is the result of a high frequency of residents in that population. I propose that sex ratios could be a valuable metric for measuring frequency of life-history tactics in populations and could facilitate the investigation into the controls of life-history tactics across broad scales. Close

• 42. [Article] Transhumance as an adaptive strategy of West Coast RV retirees

  This ethnography describes RV [recreational vehicle] seasonal migration as an adaptive, transhumant strategy. The study population is retired, transhumant migrants, who are members of a nation-wide, membership ...

  Citation × Citation Citation Abstract Copy Title: Transhumance as an adaptive strategy of West Coast RV retirees Author: Williams, Diane This ethnography describes RV [recreational vehicle] seasonal migration as an adaptive, transhumant strategy. The study population is retired, transhumant migrants, who are members of a nation-wide, membership camping organization. Fieldwork was conducted over a period of seven months at two sites located on the West Coast. These sites reflect northern and southern locations corresponding to seasonal migration patterns. Standard scholarly orientations to the study of retired RV seasonal migrants manifest ethnocentrism and a tendency to stereotype RVers as amenity-migrants. An original and primary objective of the present study was to reach beyond these conceptualizations and popularized images through first-hand, descriptive accounts collected within the context of the culture. This research expands on two existing studies focusing on social and cultural aspects of RV seasonal migration. In contrast to these accounts, the present study provides cultural description of the daily life of retired RVers focusing on the distinctive ways that members of this subculture express mainstream American cultural values underlying their adaptive strategies. This study proposes an alternative conceptualization of RV seasonal migration, derived from the culture itself. The conclusion is that these adaptive strategies reflect patterns of social organization, patterns of resource management, and patterns of social, familial, and interpersonal relationships, that are congruent with mainstream American cultural values of self-reliant individualism, equality, and material comfort; values that have historical, philosophical roots in the Protestant Work Ethic. The RVers' identity derives from maintaining membership in a temporary, fluid, mobile community. They have cohesive social networks with well-defined boundaries, which they defend against threats to group identity. This study contributes to an understanding of what RV seasonal migration means to the participants themselves, and by extension, to their families, to communities, and to our aging society. Title: Transhumance as an adaptive strategy of West Coast RV retirees Author: Williams, Diane This ethnography describes RV [recreational vehicle] seasonal migration as an adaptive, transhumant strategy. The study population is retired, transhumant migrants, who are members of a nation-wide, membership camping organization. Fieldwork was conducted over a period of seven months at two sites located on the West Coast. These sites reflect northern and southern locations corresponding to seasonal migration patterns. Standard scholarly orientations to the study of retired RV seasonal migrants manifest ethnocentrism and a tendency to stereotype RVers as amenity-migrants. An original and primary objective of the present study was to reach beyond these conceptualizations and popularized images through first-hand, descriptive accounts collected within the context of the culture. This research expands on two existing studies focusing on social and cultural aspects of RV seasonal migration. In contrast to these accounts, the present study provides cultural description of the daily life of retired RVers focusing on the distinctive ways that members of this subculture express mainstream American cultural values underlying their adaptive strategies. This study proposes an alternative conceptualization of RV seasonal migration, derived from the culture itself. The conclusion is that these adaptive strategies reflect patterns of social organization, patterns of resource management, and patterns of social, familial, and interpersonal relationships, that are congruent with mainstream American cultural values of self-reliant individualism, equality, and material comfort; values that have historical, philosophical roots in the Protestant Work Ethic. The RVers' identity derives from maintaining membership in a temporary, fluid, mobile community. They have cohesive social networks with well-defined boundaries, which they defend against threats to group identity. This study contributes to an understanding of what RV seasonal migration means to the participants themselves, and by extension, to their families, to communities, and to our aging society. Close

• 43. [Article] Housing Prices and Inter-urban Migration

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/regional-science...

  Citation × Citation Citation Abstract Copy Title: Housing Prices and Inter-urban Migration Author: Plantinga, Andrew J., Detang-Dessendre, Cécile, Hunt, Gary L., Piguet, Virginie This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/regional-science-and-urban-economics/. Title: Housing Prices and Inter-urban Migration Author: Plantinga, Andrew J., Detang-Dessendre, Cécile, Hunt, Gary L., Piguet, Virginie This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/regional-science-and-urban-economics/. Close

• 44. [Article] Utilization of the Columbia River Estuary by American shad, Alosa sapidissima (Wilson)

  The migrations, distribution, and feeding of American shad, Alosa sapidissima (Wilson), were studied from February 1980 through January 1981 in the Columbia River Estuary, an important rearing zone for young-of-the-year ...

  Citation × Citation Citation Abstract Copy Title: Utilization of the Columbia River Estuary by American shad, Alosa sapidissima (Wilson) Author: Hammann, Mark Gregory The migrations, distribution, and feeding of American shad, Alosa sapidissima (Wilson), were studied from February 1980 through January 1981 in the Columbia River Estuary, an important rearing zone for young-of-the-year shad. Sampling was performed with purse seine, beach seine, and otter trawl. Adult shad and large numbers of juveniles from the 1979 spawning (age group I) entered the estuary from the ocean in May 1980. Adults continued on their upstream migration while age group I juveniles appeared to congregate in the estuary, joining those (age group I) that had over-wintered there. Many young-of-the-year shad (age group 0) reached the estuary on their seaward migration in September 1980, during which time most of the age group I juveniles migrated back to the ocean. By January 1981, large numbers of young-of-the-year shad migrated to the ocean, although a few remained in the estuary. The stomachs of 26 adult shad and 503 juveniles were analyzed. Adults did not appear to feed during their upstream migration, but juvenile shad fed extensively. Diet varied with season, gear type, and salinity zone. Calanoid copepods were important throughout the year, but Corophium salmonis and Neomysis mercedis were important during fall, winter, and spring. Freshwater prey were consumed during summer and fall. The most important of these were Daphnia spp., Chironomidae larvae and pupae, and Trichoptera adults for shad feeding in shallow water near beaches. Title: Utilization of the Columbia River Estuary by American shad, Alosa sapidissima (Wilson) Author: Hammann, Mark Gregory The migrations, distribution, and feeding of American shad, Alosa sapidissima (Wilson), were studied from February 1980 through January 1981 in the Columbia River Estuary, an important rearing zone for young-of-the-year shad. Sampling was performed with purse seine, beach seine, and otter trawl. Adult shad and large numbers of juveniles from the 1979 spawning (age group I) entered the estuary from the ocean in May 1980. Adults continued on their upstream migration while age group I juveniles appeared to congregate in the estuary, joining those (age group I) that had over-wintered there. Many young-of-the-year shad (age group 0) reached the estuary on their seaward migration in September 1980, during which time most of the age group I juveniles migrated back to the ocean. By January 1981, large numbers of young-of-the-year shad migrated to the ocean, although a few remained in the estuary. The stomachs of 26 adult shad and 503 juveniles were analyzed. Adults did not appear to feed during their upstream migration, but juvenile shad fed extensively. Diet varied with season, gear type, and salinity zone. Calanoid copepods were important throughout the year, but Corophium salmonis and Neomysis mercedis were important during fall, winter, and spring. Freshwater prey were consumed during summer and fall. The most important of these were Daphnia spp., Chironomidae larvae and pupae, and Trichoptera adults for shad feeding in shallow water near beaches. Close

• 45. [Article] Cooperative Management of Trans-Boundary Fish Stocks: Implications for Tropical Tuna Management in the Pacific Island Region

  Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), ...

  Citation × Citation Citation Abstract Copy Title: Cooperative Management of Trans-Boundary Fish Stocks: Implications for Tropical Tuna Management in the Pacific Island Region Author: Tokunaga, Kanae Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Title: Cooperative Management of Trans-Boundary Fish Stocks: Implications for Tropical Tuna Management in the Pacific Island Region Author: Tokunaga, Kanae Suggested Bibliographic Reference: NAAFE Forum 2017 Proceedings, March 22-24, 2017. Compiled by Ann L. Shriver with assistance from Stefani Evers. North American Association of Fisheries Economists (NAAFE), Corvallis, 2017. Close

• 46. [Article] Oregon's changing rural population : age, migration and policy response

  Like rural residents in other places, people in rural Oregon have expressed concern about the demographic shifts occurring in their communities. Principally they are concerned about youth leaving and not ...

  Citation × Citation Citation Abstract Copy Title: Oregon's changing rural population : age, migration and policy response Author: Johnson, Samuel L. Like rural residents in other places, people in rural Oregon have expressed concern about the demographic shifts occurring in their communities. Principally they are concerned about youth leaving and not returning. This analysis uses recent Census Bureau data to describe, in detail, the demographic changes occurring in rural Oregon. Particular attention is paid to migration’s role in driving these changes. Interviews of community leaders in rural Oregon reveal how rural Oregon is responding to, and thinking about, these demographic changes. Results indicate that there is no comprehensive public policy in place to address the concern about demographic change. Possible policy strategies to address the demographic changes in rural Oregon are identified. Title: Oregon's changing rural population : age, migration and policy response Author: Johnson, Samuel L. Like rural residents in other places, people in rural Oregon have expressed concern about the demographic shifts occurring in their communities. Principally they are concerned about youth leaving and not returning. This analysis uses recent Census Bureau data to describe, in detail, the demographic changes occurring in rural Oregon. Particular attention is paid to migration’s role in driving these changes. Interviews of community leaders in rural Oregon reveal how rural Oregon is responding to, and thinking about, these demographic changes. Results indicate that there is no comprehensive public policy in place to address the concern about demographic change. Possible policy strategies to address the demographic changes in rural Oregon are identified. Close

• 47. [Article] Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature

  Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial ...

  Citation × Citation Citation Abstract Copy Title: Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature Author: LovellFord, Rachel Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement to spawning grounds. These cues may also provide usable habitat for migration and spawning. River discharge, temperature, and length of day have long been assumed to be the environmental cues which trigger migration and spawning of coho salmon as coho return within the same season each year to spawn. Hatchery studies have also shown that the timing of reproductive behavior is heritable. If this heritability is determined by the fluvial conditions of the spawning grounds, then a predictable relationship should exist between reproductive behavior and the hydrologic and thermal regimes. Surprisingly, no defensible correlations between discharge thresholds and spawning or migrating activity have been identified for naturally reproducing coho salmon. Thermal, velocity, and depth limitations have been identified for coho salmon, but these values have not been examined in combination or within the context of a hydrologic and thermal regime. This study compares interannual patterns in the timing of coho mid-river migration in the North Umqua (180 km up river from the estuary) and the initiation of spawn timing in the Smith River basins (Oregon) with river discharge and water temperature data to ascertain whether these behaviors are driven by fluvial conditions. Additionally, we used this data to identify the window over which most migration and spawning takes place in our test systems. On the North Umpqua, coho salmon mid-river migration initiated (first 5% of migrants) after summer peak temperatures and following a threshold average daily temperature of 18 C°, but before fall storm events occurred. In most years, approximately 75% of the migrating coho salmon have moved past the Winchester Dam before fall storms initiated and when discharge remained less than the 11 year average for the month of November, more similar to summer than winter flow levels. Additionally, characteristic lengths and numbers of peaks within the distribution of annual migrations were attributable to the generational cohort that the migration belonged to despite the similarity in population size across all years. These patterns in the distribution of generational cohorts suggest an inherited timing response as well as highlight cohorts which may contain diminished sub-populations. The initiation of coho salmon spawning appears limited both by a thermal threshold of 12 C° in all basins, as well as by a minimal discharge threshold, which is unique to each stream. Continued spawning activity occurs as discharge remains elevated from fall levels. It is also notable that there was no statistical difference in the date of the initiation of spawning within each basin in a given year or across years at a given site. Together, these studies highlight the important role that the coho salmon genome plays in reproductive timing as well as the ways that fluvial thresholds limit reproductive behavior in time. Coho have survived because of their genome has been resilient when faced with environmental change. Future work should consider variability in fluvial conditions relative to coho salmon phenotypic plasticity over time. Coho salmon phenotypic plasticity will determine whether the rate of change of the hydrologic and thermal regimes important to coho salmon survival outpaces the coho’s ability to adapt. This study contributed to this future work by establishing baseline relationships between the behavior of a threatened species and measurable environmental thresholds. Title: Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature Author: LovellFord, Rachel Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement to spawning grounds. These cues may also provide usable habitat for migration and spawning. River discharge, temperature, and length of day have long been assumed to be the environmental cues which trigger migration and spawning of coho salmon as coho return within the same season each year to spawn. Hatchery studies have also shown that the timing of reproductive behavior is heritable. If this heritability is determined by the fluvial conditions of the spawning grounds, then a predictable relationship should exist between reproductive behavior and the hydrologic and thermal regimes. Surprisingly, no defensible correlations between discharge thresholds and spawning or migrating activity have been identified for naturally reproducing coho salmon. Thermal, velocity, and depth limitations have been identified for coho salmon, but these values have not been examined in combination or within the context of a hydrologic and thermal regime. This study compares interannual patterns in the timing of coho mid-river migration in the North Umqua (180 km up river from the estuary) and the initiation of spawn timing in the Smith River basins (Oregon) with river discharge and water temperature data to ascertain whether these behaviors are driven by fluvial conditions. Additionally, we used this data to identify the window over which most migration and spawning takes place in our test systems. On the North Umpqua, coho salmon mid-river migration initiated (first 5% of migrants) after summer peak temperatures and following a threshold average daily temperature of 18 C°, but before fall storm events occurred. In most years, approximately 75% of the migrating coho salmon have moved past the Winchester Dam before fall storms initiated and when discharge remained less than the 11 year average for the month of November, more similar to summer than winter flow levels. Additionally, characteristic lengths and numbers of peaks within the distribution of annual migrations were attributable to the generational cohort that the migration belonged to despite the similarity in population size across all years. These patterns in the distribution of generational cohorts suggest an inherited timing response as well as highlight cohorts which may contain diminished sub-populations. The initiation of coho salmon spawning appears limited both by a thermal threshold of 12 C° in all basins, as well as by a minimal discharge threshold, which is unique to each stream. Continued spawning activity occurs as discharge remains elevated from fall levels. It is also notable that there was no statistical difference in the date of the initiation of spawning within each basin in a given year or across years at a given site. Together, these studies highlight the important role that the coho salmon genome plays in reproductive timing as well as the ways that fluvial thresholds limit reproductive behavior in time. Coho have survived because of their genome has been resilient when faced with environmental change. Future work should consider variability in fluvial conditions relative to coho salmon phenotypic plasticity over time. Coho salmon phenotypic plasticity will determine whether the rate of change of the hydrologic and thermal regimes important to coho salmon survival outpaces the coho’s ability to adapt. This study contributed to this future work by establishing baseline relationships between the behavior of a threatened species and measurable environmental thresholds. Close

• 48. [Article] Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA

  The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region ...

  Citation × Citation Citation Abstract Copy Title: Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA Author: Lampman, Ralph Tatsuo The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region in the past 40 to 50 years. Among the many potential causes of this decline, obstruction of migration routes has likely played a substantial role. Within the North Umpqua River basin in southwest Oregon, USA, I focused on the following three research goals: 1) to describe the passage efficiency and migration routes of adult Pacific lamprey at Winchester Dam; 2) to evaluate the seasonal movement patterns of adult Pacific lamprey and their use of holding habitat at Winchester Dam in relation to temperature conditions; and 3) to portray the diversity of upstream migratory behaviors of adult Pacific lamprey and the environmental factors that influence these behaviors. This radio telemetry study was conducted between March 2009 and August 2011 with a combination of fixed stations and manual tracking. Passage efficiency was low in both years (8% and 19%, respectively), and all tagged lamprey that successfully passed the dam used routes other than the fish ladder. Lamprey that migrated early within the run and those with relatively small tags had higher passage rates and traveled further than the other groups of lamprey. Lamprey released above of the dam or those that passed the dam on their own distributed themselves widely in the upstream environment, suggesting that the dam deterred their upstream migration. Using mark-recapture data for the two years, the adult Pacific lamprey population upstream of Winchester Dam was estimated at 960 (95% C.I. [188, 4760]) in 2009 and 556 (95% C.I. [110, 2798]) in 2010, which was considerably lower than historical counts at the dam (between 14,532-46,785 in 1965-1971). Most tagged lamprey that did not pass the dam remained at the base of the dam at the end of the summer migration (63% in 2009 and 67% in 2010). Types of habitat most frequently used by lamprey downstream from the dam included the dam surface (wooden structures with crevices), interface zones between fast and slow water, and highway bridge pilings. The lamprey movement changed considerably between August and September, and the frequency of movements decreased sharply during this period. Tagged lamprey were detected using thermal refuges immediately downstream of the dam that were 0.4 to 2.8 C° colder than the mean river temperature at the dam, and this temperature differential increased as the season progressed. Lamprey may be seeking overwintering habitat associated with hyporheic exchange flows at the dam towards the end of the summer season after their display of heightened activity early in the summer. Ninety-five percent of the overall upstream migration took place during the first spring/summer period, and only small-scale upstream movements were observed during the winter and second spring/summer (4% and 1%, respectively). The rate of upstream migration (median) was the fastest during the initial migration phase and was 1.9 km/day (ranging from 0.3 to 11.0 km/day) for tagged lamprey released above Winchester Dam. During winter, 71% of the lamprey remained in the same location where they initiated holding. Multiple regression analysis indicated that the total upstream distance traveled by individual lamprey was most strongly related to presence/absence of Winchester Dam, relative tag size, and water temperature and photoperiod conditions at release. The presence of Winchester Dam, large relative tag size, and high water temperature / short photoperiod conditions at release significantly reduced upstream migration distance. Title: Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA Author: Lampman, Ralph Tatsuo The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region in the past 40 to 50 years. Among the many potential causes of this decline, obstruction of migration routes has likely played a substantial role. Within the North Umpqua River basin in southwest Oregon, USA, I focused on the following three research goals: 1) to describe the passage efficiency and migration routes of adult Pacific lamprey at Winchester Dam; 2) to evaluate the seasonal movement patterns of adult Pacific lamprey and their use of holding habitat at Winchester Dam in relation to temperature conditions; and 3) to portray the diversity of upstream migratory behaviors of adult Pacific lamprey and the environmental factors that influence these behaviors. This radio telemetry study was conducted between March 2009 and August 2011 with a combination of fixed stations and manual tracking. Passage efficiency was low in both years (8% and 19%, respectively), and all tagged lamprey that successfully passed the dam used routes other than the fish ladder. Lamprey that migrated early within the run and those with relatively small tags had higher passage rates and traveled further than the other groups of lamprey. Lamprey released above of the dam or those that passed the dam on their own distributed themselves widely in the upstream environment, suggesting that the dam deterred their upstream migration. Using mark-recapture data for the two years, the adult Pacific lamprey population upstream of Winchester Dam was estimated at 960 (95% C.I. [188, 4760]) in 2009 and 556 (95% C.I. [110, 2798]) in 2010, which was considerably lower than historical counts at the dam (between 14,532-46,785 in 1965-1971). Most tagged lamprey that did not pass the dam remained at the base of the dam at the end of the summer migration (63% in 2009 and 67% in 2010). Types of habitat most frequently used by lamprey downstream from the dam included the dam surface (wooden structures with crevices), interface zones between fast and slow water, and highway bridge pilings. The lamprey movement changed considerably between August and September, and the frequency of movements decreased sharply during this period. Tagged lamprey were detected using thermal refuges immediately downstream of the dam that were 0.4 to 2.8 C° colder than the mean river temperature at the dam, and this temperature differential increased as the season progressed. Lamprey may be seeking overwintering habitat associated with hyporheic exchange flows at the dam towards the end of the summer season after their display of heightened activity early in the summer. Ninety-five percent of the overall upstream migration took place during the first spring/summer period, and only small-scale upstream movements were observed during the winter and second spring/summer (4% and 1%, respectively). The rate of upstream migration (median) was the fastest during the initial migration phase and was 1.9 km/day (ranging from 0.3 to 11.0 km/day) for tagged lamprey released above Winchester Dam. During winter, 71% of the lamprey remained in the same location where they initiated holding. Multiple regression analysis indicated that the total upstream distance traveled by individual lamprey was most strongly related to presence/absence of Winchester Dam, relative tag size, and water temperature and photoperiod conditions at release. The presence of Winchester Dam, large relative tag size, and high water temperature / short photoperiod conditions at release significantly reduced upstream migration distance. Close

• 49. [Article] Censuses of Black Brant at Yaquina Estuary, Lincoln County, Oregon

  Black Brant (Branta bernicla nigricans) had two different seasonal patterns of occurrence at Yaquina Estuary. At embayment areas with eelgrass (Zostera marina), Brant typically arrived between October ...

  Citation × Citation Citation Abstract Copy Title: Censuses of Black Brant at Yaquina Estuary, Lincoln County, Oregon Author: Bayer, Range D., 1947- Black Brant (Branta bernicla nigricans) had two different seasonal patterns of occurrence at Yaquina Estuary. At embayment areas with eelgrass (Zostera marina), Brant typically arrived between October 22 and November 4, Brant numbers progressively climbed in November, Brant abundance in December-January was relatively constant, and Brant numbers often fluctuated greatly during spring migration in February-April. At a site near the estuary mouth where there was little eelgrass, Brant customarily only appeared during spring migration. About 300-500 Brant wintered at the Yaquina in the 1980's, and usually fewer than 700 Brant were counted during spring migration. Title: Censuses of Black Brant at Yaquina Estuary, Lincoln County, Oregon Author: Bayer, Range D., 1947- Black Brant (Branta bernicla nigricans) had two different seasonal patterns of occurrence at Yaquina Estuary. At embayment areas with eelgrass (Zostera marina), Brant typically arrived between October 22 and November 4, Brant numbers progressively climbed in November, Brant abundance in December-January was relatively constant, and Brant numbers often fluctuated greatly during spring migration in February-April. At a site near the estuary mouth where there was little eelgrass, Brant customarily only appeared during spring migration. About 300-500 Brant wintered at the Yaquina in the 1980's, and usually fewer than 700 Brant were counted during spring migration. Close

• 50. [Article] Reconstructing Velocities of Migrating Birds from Weather Radar – A Case Study in Computational Sustainability

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Association for the Advancement of Artificial Intelligence (AAAI) and can be ...

  Citation × Citation Citation Abstract Copy Title: Reconstructing Velocities of Migrating Birds from Weather Radar – A Case Study in Computational Sustainability Author: Van Doren, Benjamin, Farnsworth, Andrew, Dietterich, Thomas G., Webb, Kevin, Kelling, Steve, Irvine, Jed, Geevarghese, Jeffrey, Sheldon, Daniel This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Association for the Advancement of Artificial Intelligence (AAAI) and can be found at: http://www.aaai.org/Magazine/magazine.php. Title: Reconstructing Velocities of Migrating Birds from Weather Radar – A Case Study in Computational Sustainability Author: Van Doren, Benjamin, Farnsworth, Andrew, Dietterich, Thomas G., Webb, Kevin, Kelling, Steve, Irvine, Jed, Geevarghese, Jeffrey, Sheldon, Daniel This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Association for the Advancement of Artificial Intelligence (AAAI) and can be found at: http://www.aaai.org/Magazine/magazine.php. Close