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• 351. [Article] Competitive interactions and resource partitioning between northern spotted owls and barred owls in western Oregon

  The federally threatened northern spotted owl (Strix occidentalis caurina) is the focus of intensive conservation efforts that have led to much forested land being reserved as habitat for the owl and associated ...

  Citation × Citation Citation Abstract Copy Title: Competitive interactions and resource partitioning between northern spotted owls and barred owls in western Oregon Author: Wiens, J. David The federally threatened northern spotted owl (Strix occidentalis caurina) is the focus of intensive conservation efforts that have led to much forested land being reserved as habitat for the owl and associated wildlife species throughout the Pacific Northwest of the United States. Recently, however, a relatively new threat to spotted owls has emerged in the form of an invasive competitor: the congeneric barred owl (Strix varia). As barred owls have rapidly expanded their populations into the entire range of the northern spotted owl, mounting evidence indicates that they are displacing, hybridizing with, and even killing spotted owls. The barred owl invasion into western North America has made an already complex conservation issue even more contentious, and a lack of information on the ecological relationships between the 2 species has hampered conservation efforts. During 2007–2009 I investigated spatial relationships, habitat selection, diets, survival, and reproduction of sympatric spotted owls and barred owls in western Oregon, USA. My overall objective was to determine the potential for and possible consequences of competition for space, habitat, and food between the 2 species. My study included 29 spotted owls and 28 barred owls that were radio-marked in 36 neighboring territories and monitored over a 24-month tracking period. Based on repeated surveys of both species, the number of territories occupied by pairs of barred owls in the 745 km² study area (82) greatly outnumbered those occupied by pairs of spotted owls (15). Estimates of mean size of home-ranges and core-use areas of spotted owls (1,843 ha and 305 ha, respectively) were 2–4 times larger than those of barred owls (581 ha and 188 ha, respectively). Individual spotted and barred owls in adjacent territories often had overlapping home ranges, but inter-specific space sharing was largely restricted to broader foraging areas in the home range with minimal spatial overlap among core-use areas. I used an information-theoretic approach to rank discrete choice models representing alternative hypotheses about the influence of forest conditions and interspecific interactions on species-specific patterns of nighttime habitat selection. Spotted owls spent a disproportionate amount of time foraging on steep slopes in ravines dominated by old (>120 yrs old) conifer trees. Barred owls used available forest types more evenly than spotted owls, and were most strongly associated with patches of large hardwood and conifer trees that occupied relatively flat areas along streams. Spotted and barred owls differed in the relative use of old conifer forest (higher for spotted owls) and slope conditions (steeper slopes for spotted owls). I found no evidence that the 2 species differed in their use of young, mature, and riparian-hardwood forest types, and both species avoided forest-nonforest edges. The best resource selection function for spotted owls indicated that the relative probability of a location being selected was reduced if the location was within or in close proximity to a core-use area of a barred owl. I used pellet analysis and measures of food niche overlap to examine the potential for dietary competition between spatially associated pairs of spotted owls and barred owls. I identified 1,223 prey items from 15 territories occupied by pairs of spotted owls and 4,299 prey items from 24 territories occupied by pairs of barred owls. Diets of both species were dominated by nocturnal mammals, but diets of barred owls included many terrestrial, aquatic, and diurnal prey species that were rare or absent in diets of spotted owls. Northern flying squirrels (Glaucomys sabrinus), woodrats (Neotoma fuscipes, N. cinerea), and lagomorphs (Lepus americanus, Sylvilagus bachmani) were particularly important prey for both owl species, accounting for 81% and 49% of total dietary biomass for spotted owls and barred owls, respectively. Dietary overlap between pairs of spotted and barred owls in adjacent territories ranged from 28–70% (mean = 42%) In addition to overlap in resource use, I also identified strong associations between the presence of barred owls and the behavior of spotted owls, as shown by changes in space-use, habitat selection, and reproductive output of spotted owls exposed to different levels of spatial overlap with barred owls in adjacent territories. Barred owls in my study area displayed both numeric and demographic superiority over spotted owls; the annual survival probability of radio-marked spotted owls from known-fate analyses (0.81, SE = 0.05) was lower than that of barred owls (0.92, SE = 0.04), and barred owls produced over 6 times as many young over a 3-year period as spotted owls. Survival of both species was positively associated with an increasing proportion of old (>120 yrs old) conifer forest within the home range, which suggested that availability of old forest was a potential limiting factor in the competitive relationship between the 2 species. When viewed collectively, my results support the hypothesis that interference competition with a high density of barred owls for territorial space can act to constrain the availability of critical resources required for successful recruitment and reproduction of spotted owls. My findings have broad implications for the conservation of spotted owls, as they suggest that spatial heterogeneity in survival and reproduction may arise not only because of differences among territories in the quality of forest habitat, but also because of the spatial distribution of an invasive competitor. Title: Competitive interactions and resource partitioning between northern spotted owls and barred owls in western Oregon Author: Wiens, J. David The federally threatened northern spotted owl (Strix occidentalis caurina) is the focus of intensive conservation efforts that have led to much forested land being reserved as habitat for the owl and associated wildlife species throughout the Pacific Northwest of the United States. Recently, however, a relatively new threat to spotted owls has emerged in the form of an invasive competitor: the congeneric barred owl (Strix varia). As barred owls have rapidly expanded their populations into the entire range of the northern spotted owl, mounting evidence indicates that they are displacing, hybridizing with, and even killing spotted owls. The barred owl invasion into western North America has made an already complex conservation issue even more contentious, and a lack of information on the ecological relationships between the 2 species has hampered conservation efforts. During 2007–2009 I investigated spatial relationships, habitat selection, diets, survival, and reproduction of sympatric spotted owls and barred owls in western Oregon, USA. My overall objective was to determine the potential for and possible consequences of competition for space, habitat, and food between the 2 species. My study included 29 spotted owls and 28 barred owls that were radio-marked in 36 neighboring territories and monitored over a 24-month tracking period. Based on repeated surveys of both species, the number of territories occupied by pairs of barred owls in the 745 km² study area (82) greatly outnumbered those occupied by pairs of spotted owls (15). Estimates of mean size of home-ranges and core-use areas of spotted owls (1,843 ha and 305 ha, respectively) were 2–4 times larger than those of barred owls (581 ha and 188 ha, respectively). Individual spotted and barred owls in adjacent territories often had overlapping home ranges, but inter-specific space sharing was largely restricted to broader foraging areas in the home range with minimal spatial overlap among core-use areas. I used an information-theoretic approach to rank discrete choice models representing alternative hypotheses about the influence of forest conditions and interspecific interactions on species-specific patterns of nighttime habitat selection. Spotted owls spent a disproportionate amount of time foraging on steep slopes in ravines dominated by old (>120 yrs old) conifer trees. Barred owls used available forest types more evenly than spotted owls, and were most strongly associated with patches of large hardwood and conifer trees that occupied relatively flat areas along streams. Spotted and barred owls differed in the relative use of old conifer forest (higher for spotted owls) and slope conditions (steeper slopes for spotted owls). I found no evidence that the 2 species differed in their use of young, mature, and riparian-hardwood forest types, and both species avoided forest-nonforest edges. The best resource selection function for spotted owls indicated that the relative probability of a location being selected was reduced if the location was within or in close proximity to a core-use area of a barred owl. I used pellet analysis and measures of food niche overlap to examine the potential for dietary competition between spatially associated pairs of spotted owls and barred owls. I identified 1,223 prey items from 15 territories occupied by pairs of spotted owls and 4,299 prey items from 24 territories occupied by pairs of barred owls. Diets of both species were dominated by nocturnal mammals, but diets of barred owls included many terrestrial, aquatic, and diurnal prey species that were rare or absent in diets of spotted owls. Northern flying squirrels (Glaucomys sabrinus), woodrats (Neotoma fuscipes, N. cinerea), and lagomorphs (Lepus americanus, Sylvilagus bachmani) were particularly important prey for both owl species, accounting for 81% and 49% of total dietary biomass for spotted owls and barred owls, respectively. Dietary overlap between pairs of spotted and barred owls in adjacent territories ranged from 28–70% (mean = 42%) In addition to overlap in resource use, I also identified strong associations between the presence of barred owls and the behavior of spotted owls, as shown by changes in space-use, habitat selection, and reproductive output of spotted owls exposed to different levels of spatial overlap with barred owls in adjacent territories. Barred owls in my study area displayed both numeric and demographic superiority over spotted owls; the annual survival probability of radio-marked spotted owls from known-fate analyses (0.81, SE = 0.05) was lower than that of barred owls (0.92, SE = 0.04), and barred owls produced over 6 times as many young over a 3-year period as spotted owls. Survival of both species was positively associated with an increasing proportion of old (>120 yrs old) conifer forest within the home range, which suggested that availability of old forest was a potential limiting factor in the competitive relationship between the 2 species. When viewed collectively, my results support the hypothesis that interference competition with a high density of barred owls for territorial space can act to constrain the availability of critical resources required for successful recruitment and reproduction of spotted owls. My findings have broad implications for the conservation of spotted owls, as they suggest that spatial heterogeneity in survival and reproduction may arise not only because of differences among territories in the quality of forest habitat, but also because of the spatial distribution of an invasive competitor. Close

• 352. [Article] Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA

  Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future ...

  Citation × Citation Citation Abstract Copy Title: Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA Author: Kennedy, Rebecca S.H. Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition. Title: Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA Author: Kennedy, Rebecca S.H. Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition. Close

• 353. [Article] Community conflict : a case study of the implementation of a bilingual education program

  This research project is an historical case study of the conflict which evolved from the deliberations and subsequent implementation of bilingual education in Central School District 13J, Independence, Oregon. ...

  Citation × Citation Citation Abstract Copy Title: Community conflict : a case study of the implementation of a bilingual education program Author: Guzmán, Juan This research project is an historical case study of the conflict which evolved from the deliberations and subsequent implementation of bilingual education in Central School District 13J, Independence, Oregon. The time period under consideration spans 35 months, beginning in August 1974, when district officials first proposed bilingual education, and ending in June 1977, when the first year of bilingual education in the district was completed. Investigation of the conflict in Independence was guided by the following questions. 1. What is the nature of the conflict resulting from the bilingual education issue in Independence, Oregon? 2. To what extent does this conflict affect educational policy? 3. What is the nature of community influence regarding school decisions and educational policy? The investigation of these questions required that two types of data be gathered. The first type--news media reporting, county and school district surveys, personal correspondence, government records--provided an historical perspective for considering the district's decision to implement bilingual education. The second type of data--personal interviews and informal conversations--addressed the need for bilingual education in Independence, the policy making process, and community involvement in decision-making. Conclusions: The conflict which surfaced in the small community of Independence is rooted in the value conflict--assimilation vs. cultural pluralism. Two conflicting views have emerged in Independence regarding the role of public education as a transmitter of culture. One perspective endorses pluralism in society and encourages bilingual education as one means of accommodating pluralism. An opposing viewpoint supports traditional educational practices which support the assimilation of ethnic and racial minorities through the promotion of a single language and culture. The question of whether public education is responsible for promoting cultural homogeneity or the lesser accepted concept of cultural pluralism still remains unresolved in Independence as in other parts of the nation. Supporters for each viewpoint seem unwilling to compromise, thus prolonging the value conflict in the community. The value conflict existing in Independence has not been recognized as such by the community. Rather, this conflict is being viewed as mere misunderstandings due to poor communications between supporters of pluralism and defenders of assimilation. By refusing to recognize the existence of value conflict, the school district, Chicano parents, and the community at large have avoided any real confrontation with the status quo regarding bilingual education. Because the value conflict which presently exists within the Independence community is not acknowledged, it can have no effect on educational policy per se. Throughout its existence, the bilingual education program has not prompted community activism either for or against the program. The sporadic and limited nature of community participation and influence in decision-making has not changed because of bilingual education, and it appears that maintaining the status quo regarding bilingual education in School District 13J has become preferable to seeking change through district policy. Title: Community conflict : a case study of the implementation of a bilingual education program Author: Guzmán, Juan This research project is an historical case study of the conflict which evolved from the deliberations and subsequent implementation of bilingual education in Central School District 13J, Independence, Oregon. The time period under consideration spans 35 months, beginning in August 1974, when district officials first proposed bilingual education, and ending in June 1977, when the first year of bilingual education in the district was completed. Investigation of the conflict in Independence was guided by the following questions. 1. What is the nature of the conflict resulting from the bilingual education issue in Independence, Oregon? 2. To what extent does this conflict affect educational policy? 3. What is the nature of community influence regarding school decisions and educational policy? The investigation of these questions required that two types of data be gathered. The first type--news media reporting, county and school district surveys, personal correspondence, government records--provided an historical perspective for considering the district's decision to implement bilingual education. The second type of data--personal interviews and informal conversations--addressed the need for bilingual education in Independence, the policy making process, and community involvement in decision-making. Conclusions: The conflict which surfaced in the small community of Independence is rooted in the value conflict--assimilation vs. cultural pluralism. Two conflicting views have emerged in Independence regarding the role of public education as a transmitter of culture. One perspective endorses pluralism in society and encourages bilingual education as one means of accommodating pluralism. An opposing viewpoint supports traditional educational practices which support the assimilation of ethnic and racial minorities through the promotion of a single language and culture. The question of whether public education is responsible for promoting cultural homogeneity or the lesser accepted concept of cultural pluralism still remains unresolved in Independence as in other parts of the nation. Supporters for each viewpoint seem unwilling to compromise, thus prolonging the value conflict in the community. The value conflict existing in Independence has not been recognized as such by the community. Rather, this conflict is being viewed as mere misunderstandings due to poor communications between supporters of pluralism and defenders of assimilation. By refusing to recognize the existence of value conflict, the school district, Chicano parents, and the community at large have avoided any real confrontation with the status quo regarding bilingual education. Because the value conflict which presently exists within the Independence community is not acknowledged, it can have no effect on educational policy per se. Throughout its existence, the bilingual education program has not prompted community activism either for or against the program. The sporadic and limited nature of community participation and influence in decision-making has not changed because of bilingual education, and it appears that maintaining the status quo regarding bilingual education in School District 13J has become preferable to seeking change through district policy. Close

• 354. [Article] Stable occupancy by breeding hawks (Buteo spp.) over 25 years on a privately managed bunchgrass prairie in northeastern Oregon, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Cooper ...

  Citation × Citation Citation Abstract Copy Title: Stable occupancy by breeding hawks (Buteo spp.) over 25 years on a privately managed bunchgrass prairie in northeastern Oregon, USA Author: Bartuszevige, Anne M., Humphrey, Ann B., Houle, Marcy, Kennedy, Patricia L., Dugger, Katie M., Williams, John To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Cooper Ornithological Society and can be found at: http://www.bioone.org/loi/cond. Title: Stable occupancy by breeding hawks (Buteo spp.) over 25 years on a privately managed bunchgrass prairie in northeastern Oregon, USA Author: Bartuszevige, Anne M., Humphrey, Ann B., Houle, Marcy, Kennedy, Patricia L., Dugger, Katie M., Williams, John To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Cooper Ornithological Society and can be found at: http://www.bioone.org/loi/cond. Close

• 355. [Article] Who we are and will be

  The protagonists in the fiction of Paule Marshall, Alice Walker, and Toni Morrison illuminate American cultural perceptions of black women and illustrate how the creators of these characters hope to change ...

  Citation × Citation Citation Abstract Copy Title: Who we are and will be Author: Jackson, Linda Carol, 1949- The protagonists in the fiction of Paule Marshall, Alice Walker, and Toni Morrison illuminate American cultural perceptions of black women and illustrate how the creators of these characters hope to change those perceptions. I studied Paule Marshall's Daughters, Alice Walker's Meridian and The Color Purple, and Toni Morrison's The Bluest Eye to learn what the writers of these novels have to say about the women they hope black girls can grow up to be and to learn what potential for self-development they see for black women. For example, in order to become whole people, what do black girls and black women need from their parents and their community? What do black women need from their intimate relationships? "Part One: Political, Historical and Religious Identity " surveys politics, religion and history for views of black women. Politically, they appear disenfranchised; historically they were property. In reference to religion, I found that a white male religion does not serve black women well. Walker sees god within her female protagonist Celie, and Marshall has a belief in a Caribbean/African diaspora that provides a sense of spiritual and cultural continuity. "Part Two: Childhood Identity" explores childhood and the community's role. Childhood appears as a critical time for self-development. The adults in the community contribute to the child's self-awareness. Mistreatment of girls causes them harm throughout their lives. How well the community safeguards its children is a measure of how highly these children are valued. These authors want to see girls more highly regarded. Toward this end, they expose the abuse that takes place in the community. Morrison shows not only the abuse, but also the love. By showing concerned parents as well as neglectful ones, Morrison offers a fuller portrait of the community she knows. The Color Purple also tells a story of sexual abuse of a girl, but this abuse is overcome by the inner strength of the victim combined with the loving support of Shug Avery and the supportive community context of the juke where Celie is accepted. The portrayal of childhood in Daughters involves a Caribbean island culture where the roles of the women that the child Ursa observes offer few role models. "Part Three: Adult Relational Identity" looks at the dilemma in communication between the sexes and across the generations from mother to daughter. Step-fathers and husbands are abusive characters in Walker's writing, while Morrison shows a loving father and an incestuous father in The Bluest Eye. "Part Four: Language Identity" discusses Black English, orality and dialect, looking at the role of language as an aspect of self-definition. James Baldwin's view of language is presented: rejecting a child's language is rejecting the child himself. Baldwin's view supports the attitude toward language as self-defining that appears in the writing of Marshall, Morrison, and Walker. These authors show pride in Black English, and they demonstrate their ability with edited English through their own writing. Title: Who we are and will be Author: Jackson, Linda Carol, 1949- The protagonists in the fiction of Paule Marshall, Alice Walker, and Toni Morrison illuminate American cultural perceptions of black women and illustrate how the creators of these characters hope to change those perceptions. I studied Paule Marshall's Daughters, Alice Walker's Meridian and The Color Purple, and Toni Morrison's The Bluest Eye to learn what the writers of these novels have to say about the women they hope black girls can grow up to be and to learn what potential for self-development they see for black women. For example, in order to become whole people, what do black girls and black women need from their parents and their community? What do black women need from their intimate relationships? "Part One: Political, Historical and Religious Identity " surveys politics, religion and history for views of black women. Politically, they appear disenfranchised; historically they were property. In reference to religion, I found that a white male religion does not serve black women well. Walker sees god within her female protagonist Celie, and Marshall has a belief in a Caribbean/African diaspora that provides a sense of spiritual and cultural continuity. "Part Two: Childhood Identity" explores childhood and the community's role. Childhood appears as a critical time for self-development. The adults in the community contribute to the child's self-awareness. Mistreatment of girls causes them harm throughout their lives. How well the community safeguards its children is a measure of how highly these children are valued. These authors want to see girls more highly regarded. Toward this end, they expose the abuse that takes place in the community. Morrison shows not only the abuse, but also the love. By showing concerned parents as well as neglectful ones, Morrison offers a fuller portrait of the community she knows. The Color Purple also tells a story of sexual abuse of a girl, but this abuse is overcome by the inner strength of the victim combined with the loving support of Shug Avery and the supportive community context of the juke where Celie is accepted. The portrayal of childhood in Daughters involves a Caribbean island culture where the roles of the women that the child Ursa observes offer few role models. "Part Three: Adult Relational Identity" looks at the dilemma in communication between the sexes and across the generations from mother to daughter. Step-fathers and husbands are abusive characters in Walker's writing, while Morrison shows a loving father and an incestuous father in The Bluest Eye. "Part Four: Language Identity" discusses Black English, orality and dialect, looking at the role of language as an aspect of self-definition. James Baldwin's view of language is presented: rejecting a child's language is rejecting the child himself. Baldwin's view supports the attitude toward language as self-defining that appears in the writing of Marshall, Morrison, and Walker. These authors show pride in Black English, and they demonstrate their ability with edited English through their own writing. Close

• 356. [Article] Effects of oil and natural gas development on territory occupancy of ferruginous hawks and golden eagles in Wyoming, USA

  Energy development is expanding rapidly across the western US. Negative effects have been documented for some wildlife, but consequences of development are unclear for other taxa, including raptors. We ...

  Citation × Citation Citation Abstract Copy Title: Effects of oil and natural gas development on territory occupancy of ferruginous hawks and golden eagles in Wyoming, USA Author: Wallace, Zachary P. Energy development is expanding rapidly across the western US. Negative effects have been documented for some wildlife, but consequences of development are unclear for other taxa, including raptors. We had the opportunity to examine effects of oil and natural gas development on two raptor species of conservation concern, ferruginous hawks (Buteo regalis) and golden eagles (Aquila chrysaetos), in sagebrush steppe and prairie habitats of Wyoming. We surveyed nest sites of these species using fixed-wing aircraft during 2010–2011, and monitored occupancy of the resulting sample of historically active breeding territories during 2011–2013 for ferruginous hawks, and 2012–2013 for golden eagles. We used single-season occupancy models to evaluate post-construction effects of oil and natural gas development in the context of other factors predicted to influence use of territories by these species, including prey abundance, nest site characteristics, and vegetation. An additional objective was to demonstrate a monitoring protocol for raptors in Wyoming that used probabilistic sampling and accounted for imperfect detection. In support of our predictions, probability of territory occupancy by ferruginous hawks had a strong positive relationship to abundance of ground squirrels (Urocitellus spp.), a strong negative relationship to vegetative cover of sagebrush (Artemisia spp.), and was slightly higher for artificial nest platforms compared to other substrates; and territory occupancy for golden eagles had a strong positive relationship to nest height. Contrary to our predictions, density of oil and natural gas infrastructure was not strongly related to occupancy for either species, and prey abundance was not related to occupancy for golden eagles. The only anthropogenic factor that influenced occupancy for either species was density of improved roads not associated with oil and natural gas fields, which had a weak positive correlation with occupancy for ferruginous hawks, contrary to our predictions. Annual occupancy probability did not vary significantly for either species during our study, but environmental factors associated with occupancy and the strength of relationships varied among years for both species, suggesting occupancy was influenced by additional factors not included in our analysis (e.g. weather, regional dynamics). Detection probability for both species was <1, and strongly influenced by nest substrates. For ferruginous hawks, detection probability varied significantly between years, and was positively associated with nest height. For golden eagles, detection probability was significantly higher in territories with nests on trees, shrubs, and anthropogenic structures, compared to those on cliffs and rock outcrops, with a weak negative trend in detection rates across survey occasions during one year. Our results suggest ferruginous hawks and golden eagles used breeding territories that contained active oil and gas roads and well pads, and density of infrastructure in these territories did not affect their probability of use. However, we advise that limitations of our approach (i.e. post-construction, short-term, observational study) make our results most relevant as a baseline for ongoing monitoring of these species. We suggest protection efforts should be focused on ferruginous hawk territories with abundant ground squirrels and low natural cover of sagebrush, and golden eagle territories with higher nest sites. We recommend conserving populations and habitats of burrowing mammals, mitigating loss of nests using artificial platforms, and long-term monitoring of ferruginous hawks and golden eagles using robust methods that account for imperfect detection. Title: Effects of oil and natural gas development on territory occupancy of ferruginous hawks and golden eagles in Wyoming, USA Author: Wallace, Zachary P. Energy development is expanding rapidly across the western US. Negative effects have been documented for some wildlife, but consequences of development are unclear for other taxa, including raptors. We had the opportunity to examine effects of oil and natural gas development on two raptor species of conservation concern, ferruginous hawks (Buteo regalis) and golden eagles (Aquila chrysaetos), in sagebrush steppe and prairie habitats of Wyoming. We surveyed nest sites of these species using fixed-wing aircraft during 2010–2011, and monitored occupancy of the resulting sample of historically active breeding territories during 2011–2013 for ferruginous hawks, and 2012–2013 for golden eagles. We used single-season occupancy models to evaluate post-construction effects of oil and natural gas development in the context of other factors predicted to influence use of territories by these species, including prey abundance, nest site characteristics, and vegetation. An additional objective was to demonstrate a monitoring protocol for raptors in Wyoming that used probabilistic sampling and accounted for imperfect detection. In support of our predictions, probability of territory occupancy by ferruginous hawks had a strong positive relationship to abundance of ground squirrels (Urocitellus spp.), a strong negative relationship to vegetative cover of sagebrush (Artemisia spp.), and was slightly higher for artificial nest platforms compared to other substrates; and territory occupancy for golden eagles had a strong positive relationship to nest height. Contrary to our predictions, density of oil and natural gas infrastructure was not strongly related to occupancy for either species, and prey abundance was not related to occupancy for golden eagles. The only anthropogenic factor that influenced occupancy for either species was density of improved roads not associated with oil and natural gas fields, which had a weak positive correlation with occupancy for ferruginous hawks, contrary to our predictions. Annual occupancy probability did not vary significantly for either species during our study, but environmental factors associated with occupancy and the strength of relationships varied among years for both species, suggesting occupancy was influenced by additional factors not included in our analysis (e.g. weather, regional dynamics). Detection probability for both species was <1, and strongly influenced by nest substrates. For ferruginous hawks, detection probability varied significantly between years, and was positively associated with nest height. For golden eagles, detection probability was significantly higher in territories with nests on trees, shrubs, and anthropogenic structures, compared to those on cliffs and rock outcrops, with a weak negative trend in detection rates across survey occasions during one year. Our results suggest ferruginous hawks and golden eagles used breeding territories that contained active oil and gas roads and well pads, and density of infrastructure in these territories did not affect their probability of use. However, we advise that limitations of our approach (i.e. post-construction, short-term, observational study) make our results most relevant as a baseline for ongoing monitoring of these species. We suggest protection efforts should be focused on ferruginous hawk territories with abundant ground squirrels and low natural cover of sagebrush, and golden eagle territories with higher nest sites. We recommend conserving populations and habitats of burrowing mammals, mitigating loss of nests using artificial platforms, and long-term monitoring of ferruginous hawks and golden eagles using robust methods that account for imperfect detection. Close

• 357. [Article] Fault behavior over geomorphic time scales in the Pakistan Himalaya, Kashmir Himalaya, and California

  The state of the knowledge for fault behavior in the northwest Himalaya and California varies dramatically. In the Pakistan and Kashmir Himalaya, few data constrain the role that individual active faults ...

  Citation × Citation Citation Abstract Copy Title: Fault behavior over geomorphic time scales in the Pakistan Himalaya, Kashmir Himalaya, and California Author: Madugo, Christopher Lee Madden The state of the knowledge for fault behavior in the northwest Himalaya and California varies dramatically. In the Pakistan and Kashmir Himalaya, few data constrain the role that individual active faults play in accommodating Indo-Eurasian convergence and the relative earthquake hazard across the region. By contrast, the San Andreas fault in California is one of the best-studied fault systems in the world, although seismic hazard models have yet to incorporate certain available geologic data, such as measurements of slip-in-the-last-event. This dissertation addresses the sparsity of earthquake hazard data in the northwest Himalaya, and the problem of how best to utilize available data in hazard models for California by (1) Providing the first quantitative constraints on the latest Pleistocene slip rate and earthquake potential for the thrust front Pakistan; (2) Characterizing the rate and style of upper plate faulting in Kashmir over geomorphic (10⁴ year) time scales; and (3) Creating a standardized database of fault offsets to help test time-dependent and time-independent seismic hazard models for the Uniform California Rupture Forecast. The Himalayan thrust front in Pakistan is defined by the Salt Range thrust (SRT), the up-dip extension of the plate boundary décollement, the Main Himalayan thrust (MHT). We constrain the convergence rate across the SRT by determining the slip rate for the Kalabagh fault (KF), a tear fault that is linked with the SRT at depth. Based on the age and offset of two alluvial fan apexes from their source canyons, we estimate a slip rate of between 9 and 27 mm/yr (~12-17 mm/yr best estimate) for the KF-SRT fault system. This rate matches well with the geodetically-constrained creep rate for the MHT at depth, suggesting the entire slip budget for the Pakistan Himalaya is accommodated at the thrust front. Because the SRT is cored by salt, the earthquake potential for the fault is inferred to be low, although evidence for seismogenic Holocene rupture on the Kalabagh fault, which is also locally lined with salt, suggests that the frontal fault ruptures in plate boundary earthquakes on the MHT. The primary implications of these findings are that convergence in the Pakistan Himalaya is focused at the thrust front rather than distributed between different faults across the plate boundary. In the Kashmir Himalaya, multiple active faults along the plate boundary suggest that Indo-Eurasian convergence is partitioned between the thrust front and faults to the north. To test how much deformation occurs within the overriding plate, we characterized deformation for the Balapora fault, a high-angle reverse fault on the southwest side of the Kashmir Valley. Based on dated offset stream terraces and alluvial fans, the slip rate for the Balapora fault is consistently between 0.3 and 0.5 mm/yr over time scales varying by an order magnitude between about 40 ka and 400 ka. These slip rates translate to shortening rates of 0.1 mm/yr, or less than 1% of the convergence rate across the Kashmir Himalaya. Earthquake recurrence for the Balapora fault is several thousand years, which is consistent with the low slip rate for the fault. The inference is thus that, the majority of convergence in the Kashmir Himalaya is accommodated near the thrust front, as in the Pakistan Himalaya. For California, a new database was created from thousands of measurements of slip resulting from one or more historical to prehistoric earthquakes for use in seismic hazard models. A new rating scheme characterizes the quality of the offsets. Multiple methods to estimate slip during the last event, average slip and slip-per-event are used to analyze the data. These data provide a first order check for models of earthquake behavior. With the advent of high resolution topographic datasets such as LiDAR, the new methodology serves as a template for inclusion of rapidly-accumulating topographic and paleoseismic data in California as well as to regions such as the Himalayan front, as those types of data are adopted. Title: Fault behavior over geomorphic time scales in the Pakistan Himalaya, Kashmir Himalaya, and California Author: Madugo, Christopher Lee Madden The state of the knowledge for fault behavior in the northwest Himalaya and California varies dramatically. In the Pakistan and Kashmir Himalaya, few data constrain the role that individual active faults play in accommodating Indo-Eurasian convergence and the relative earthquake hazard across the region. By contrast, the San Andreas fault in California is one of the best-studied fault systems in the world, although seismic hazard models have yet to incorporate certain available geologic data, such as measurements of slip-in-the-last-event. This dissertation addresses the sparsity of earthquake hazard data in the northwest Himalaya, and the problem of how best to utilize available data in hazard models for California by (1) Providing the first quantitative constraints on the latest Pleistocene slip rate and earthquake potential for the thrust front Pakistan; (2) Characterizing the rate and style of upper plate faulting in Kashmir over geomorphic (10⁴ year) time scales; and (3) Creating a standardized database of fault offsets to help test time-dependent and time-independent seismic hazard models for the Uniform California Rupture Forecast. The Himalayan thrust front in Pakistan is defined by the Salt Range thrust (SRT), the up-dip extension of the plate boundary décollement, the Main Himalayan thrust (MHT). We constrain the convergence rate across the SRT by determining the slip rate for the Kalabagh fault (KF), a tear fault that is linked with the SRT at depth. Based on the age and offset of two alluvial fan apexes from their source canyons, we estimate a slip rate of between 9 and 27 mm/yr (~12-17 mm/yr best estimate) for the KF-SRT fault system. This rate matches well with the geodetically-constrained creep rate for the MHT at depth, suggesting the entire slip budget for the Pakistan Himalaya is accommodated at the thrust front. Because the SRT is cored by salt, the earthquake potential for the fault is inferred to be low, although evidence for seismogenic Holocene rupture on the Kalabagh fault, which is also locally lined with salt, suggests that the frontal fault ruptures in plate boundary earthquakes on the MHT. The primary implications of these findings are that convergence in the Pakistan Himalaya is focused at the thrust front rather than distributed between different faults across the plate boundary. In the Kashmir Himalaya, multiple active faults along the plate boundary suggest that Indo-Eurasian convergence is partitioned between the thrust front and faults to the north. To test how much deformation occurs within the overriding plate, we characterized deformation for the Balapora fault, a high-angle reverse fault on the southwest side of the Kashmir Valley. Based on dated offset stream terraces and alluvial fans, the slip rate for the Balapora fault is consistently between 0.3 and 0.5 mm/yr over time scales varying by an order magnitude between about 40 ka and 400 ka. These slip rates translate to shortening rates of 0.1 mm/yr, or less than 1% of the convergence rate across the Kashmir Himalaya. Earthquake recurrence for the Balapora fault is several thousand years, which is consistent with the low slip rate for the fault. The inference is thus that, the majority of convergence in the Kashmir Himalaya is accommodated near the thrust front, as in the Pakistan Himalaya. For California, a new database was created from thousands of measurements of slip resulting from one or more historical to prehistoric earthquakes for use in seismic hazard models. A new rating scheme characterizes the quality of the offsets. Multiple methods to estimate slip during the last event, average slip and slip-per-event are used to analyze the data. These data provide a first order check for models of earthquake behavior. With the advent of high resolution topographic datasets such as LiDAR, the new methodology serves as a template for inclusion of rapidly-accumulating topographic and paleoseismic data in California as well as to regions such as the Himalayan front, as those types of data are adopted. Close

• 358. [Article] Disease resistance and spring phenological characteristics of Ribes L. germplasm

  North American cultivation of Ribes L. may expand as small fruit growers seek species to diversify horticultural crops. The Ribes industry was suppressed for decades out of fear that cultivated black currants ...

  Citation × Citation Citation Abstract Copy Title: Disease resistance and spring phenological characteristics of Ribes L. germplasm Author: Dalton, Daniel T. North American cultivation of Ribes L. may expand as small fruit growers seek species to diversify horticultural crops. The Ribes industry was suppressed for decades out of fear that cultivated black currants and gooseberries would intensify the fungal disease white pine blister rust (WPBR) on five-needle pine (Pinus L. section Quinquefoliae) species. These pines were historically vital to the timber industry. Today, plant breeders seek to strengthen the Ribes small fruit industry through production of material suitable for North American conditions. Paramount to this effort is the development of resistance against major pests and diseases. Growers must be able to recognize the attributes of available genotypes prior to field establishment. The objectives of this research were to determine disease resistance and phenological characteristics of Ribes selections at the United States Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. Since the early 1930's, plant breeders have used immune black currant (R. nigrum L.) germplasm as a control tactic against the exotic WPBR, caused by the basidiomycete fungus Cronartium ribicola J.C. Fischer. In 1999, a seedling population was generated at the NCGR from a cross involving susceptible pistillate R. nigrum 'Ben Lomond' and immune staminate parent R. ussuriense Jancz. x R. nigrum 'Consort.' To test the inheritance of resistance in the F₁ population, aeciospore and urediniospore treatments were applied in 2008 to single-leaf softwood cuttings under controlled conditions in a greenhouse. Resistant F₁ phenotypes segregated in a 1:1 ratio consistent with the pattern of simple dominant inheritance of a single gene. Artificial inoculations testing aeciospore and urediniospore infectivity produced equivalent disease severity in the experimental Ribes genotypes. Resistance to the native powdery mildew fungus, Podosphaera mors-uvae (Schwein.) U. Brown and S. Takamatsu, was also evaluated in the F₁ population. Individuals segregated for resistance in a 1:3 ratio after exposure to elevated disease pressure in the greenhouse. Fifteen F₁ genotypes were resistant to both fungal pathogens and are candidates for further breeding trials. In a second study, five years of spring phenological survey data were analyzed using a growing degree-day (GDD) model, with the objective to identify cultivars adapted to North American conditions. Ribes section Calobotrya was the earliest group to reach "first bloom," followed sequentially by R. [superscript]xnidigrolaria Bauer hybrid species, section Symphocalyx, section Grossularia, section Ribes, and lastly, section Botrycarpum. Early and late-flowering accessions were identified for each taxon. Title: Disease resistance and spring phenological characteristics of Ribes L. germplasm Author: Dalton, Daniel T. North American cultivation of Ribes L. may expand as small fruit growers seek species to diversify horticultural crops. The Ribes industry was suppressed for decades out of fear that cultivated black currants and gooseberries would intensify the fungal disease white pine blister rust (WPBR) on five-needle pine (Pinus L. section Quinquefoliae) species. These pines were historically vital to the timber industry. Today, plant breeders seek to strengthen the Ribes small fruit industry through production of material suitable for North American conditions. Paramount to this effort is the development of resistance against major pests and diseases. Growers must be able to recognize the attributes of available genotypes prior to field establishment. The objectives of this research were to determine disease resistance and phenological characteristics of Ribes selections at the United States Department of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. Since the early 1930's, plant breeders have used immune black currant (R. nigrum L.) germplasm as a control tactic against the exotic WPBR, caused by the basidiomycete fungus Cronartium ribicola J.C. Fischer. In 1999, a seedling population was generated at the NCGR from a cross involving susceptible pistillate R. nigrum 'Ben Lomond' and immune staminate parent R. ussuriense Jancz. x R. nigrum 'Consort.' To test the inheritance of resistance in the F₁ population, aeciospore and urediniospore treatments were applied in 2008 to single-leaf softwood cuttings under controlled conditions in a greenhouse. Resistant F₁ phenotypes segregated in a 1:1 ratio consistent with the pattern of simple dominant inheritance of a single gene. Artificial inoculations testing aeciospore and urediniospore infectivity produced equivalent disease severity in the experimental Ribes genotypes. Resistance to the native powdery mildew fungus, Podosphaera mors-uvae (Schwein.) U. Brown and S. Takamatsu, was also evaluated in the F₁ population. Individuals segregated for resistance in a 1:3 ratio after exposure to elevated disease pressure in the greenhouse. Fifteen F₁ genotypes were resistant to both fungal pathogens and are candidates for further breeding trials. In a second study, five years of spring phenological survey data were analyzed using a growing degree-day (GDD) model, with the objective to identify cultivars adapted to North American conditions. Ribes section Calobotrya was the earliest group to reach "first bloom," followed sequentially by R. [superscript]xnidigrolaria Bauer hybrid species, section Symphocalyx, section Grossularia, section Ribes, and lastly, section Botrycarpum. Early and late-flowering accessions were identified for each taxon. Close

• 359. [Article] Biogeography of nonindigenous species: from description to prediction

  Nonindigenous species are a major threat to the ecological integrity and biodiversity of marine and estuarine ecosystems. To become a successful invader, species must pass through four phases: (1) survive ...

  Citation × Citation Citation Abstract Copy Title: Biogeography of nonindigenous species: from description to prediction Author: Reusser, Deborah A. Nonindigenous species are a major threat to the ecological integrity and biodiversity of marine and estuarine ecosystems. To become a successful invader, species must pass through four phases: (1) survive transport, (2) survive release, (3) establish a population, and (4) expand their range. To better understand these processes, an integrated framework was designed to capture life history characteristics, environmental preferences, dispersal mechanisms, and geographic distribution information for both native and nonindigenous marine and estuarine flora and fauna. Key aspects of this framework include: 1) consistent terminology; 2) translation of numerical habitat values and physiological requirements into classes; 3) development of classification schemas for natural history, environmental attributes, and geographic distributions; and 4) integration of biotic attributes to allow database queries on single or multiple species across spatial scales. Species data for the North Pacific were collected from the literature, local surveys, and regional databases. Ballast water discharges have been identified as a major source of species introductions. To predict the potential rate of invasion from ballast water, a linear invasion model predicting per capita invasion probabilities (PCIP) of new invaders was developed based on historic invasion rates and ballast discharge volumes for estuaries on the west coast of the United States. While the probability of invasion is likely to vary with ballast discharge values, organism concentrations in the ballast, and invasibility of individual ports, the PCIP provides a quantitative methodology for establishing protective ballast water discharge standards based on organism concentrations, the approach being used to regulate ballast water discharges both nationally and internationally. Habitat or niche models can be used to predict a nonindigenous species’ potential distribution in invaded areas over several spatial scales. The utility of non-parametric multiplicative regression (NPMR) was evaluated for predicting habitat- and estuary-scale distributions of native and nonindigenous species. Results indicate that NPMR generally performs well at both spatial scales and that distributions of nonindigenous species are predicted as well as those of native species. Development of approaches for regulating ballast water and identifying areas at risk through predictive modeling are useful tools in the management of the nonindigenous species threat. Title: Biogeography of nonindigenous species: from description to prediction Author: Reusser, Deborah A. Nonindigenous species are a major threat to the ecological integrity and biodiversity of marine and estuarine ecosystems. To become a successful invader, species must pass through four phases: (1) survive transport, (2) survive release, (3) establish a population, and (4) expand their range. To better understand these processes, an integrated framework was designed to capture life history characteristics, environmental preferences, dispersal mechanisms, and geographic distribution information for both native and nonindigenous marine and estuarine flora and fauna. Key aspects of this framework include: 1) consistent terminology; 2) translation of numerical habitat values and physiological requirements into classes; 3) development of classification schemas for natural history, environmental attributes, and geographic distributions; and 4) integration of biotic attributes to allow database queries on single or multiple species across spatial scales. Species data for the North Pacific were collected from the literature, local surveys, and regional databases. Ballast water discharges have been identified as a major source of species introductions. To predict the potential rate of invasion from ballast water, a linear invasion model predicting per capita invasion probabilities (PCIP) of new invaders was developed based on historic invasion rates and ballast discharge volumes for estuaries on the west coast of the United States. While the probability of invasion is likely to vary with ballast discharge values, organism concentrations in the ballast, and invasibility of individual ports, the PCIP provides a quantitative methodology for establishing protective ballast water discharge standards based on organism concentrations, the approach being used to regulate ballast water discharges both nationally and internationally. Habitat or niche models can be used to predict a nonindigenous species’ potential distribution in invaded areas over several spatial scales. The utility of non-parametric multiplicative regression (NPMR) was evaluated for predicting habitat- and estuary-scale distributions of native and nonindigenous species. Results indicate that NPMR generally performs well at both spatial scales and that distributions of nonindigenous species are predicted as well as those of native species. Development of approaches for regulating ballast water and identifying areas at risk through predictive modeling are useful tools in the management of the nonindigenous species threat. Close

• 360. [Article] Habitat characteristics associated with abundance of band-tailed pigeons and use of mineral sites in the Pacific Northwest

  Index counts for the Pacific Coast race of the band-tailed pigeon (Columba fasciata monilis) have declined by -2% per year since survey efforts began in the 1950's and 60's. Mineral sites, important resources ...

  Citation × Citation Citation Abstract Copy Title: Habitat characteristics associated with abundance of band-tailed pigeons and use of mineral sites in the Pacific Northwest Author: Overton, Cory T. Index counts for the Pacific Coast race of the band-tailed pigeon (Columba fasciata monilis) have declined by -2% per year since survey efforts began in the 1950's and 60's. Mineral sites, important resources with high ion concentrations, are regularly visited by band-tailed pigeons which nest in surrounding forest lands. I used both ad hoc measurements of mineral site characteristics and composition and configuration of habitat types adjacent to mineral sites to develop models predicting band-tailed pigeon abundance at mineral sites, in the Pacific Northwest. Band-tailed pigeons were counted weekly during the summers of 2001 and 2002 at 20 mineral sites. Since, many mineral sites have been abandoned by band-tailed pigeons, I tested for an association between land use types mineral site use by band-tailed pigeons using a database of 69 currently used and 20 historically used mineral sites in Oregon. Lastly, I investigated the association between the timing and duration of precipitation on index counts of band-tailed pigeons at 20 mineral sites. Abundance of band-tailed pigeons was positively associated with habitat dominance, (i.e. 1-Shannon's Evenness or homogeneity of landcover types) at a scale larger than band-tailed pigeon home range size and with distance to the nearest adjacent mineral site. Both a quadratic effect of latitude and use of an indicator variable for regional variation in abundance were also present in top ranked models. Both latitudinal effects predicted an increase in birds from central Oregon to southern Washington, then a decrease from central Washington to British Columbia. My findings suggest that: 1) large areas of homogeneous landcover are important for band-tailed pigeons, 2) distribution of mineral sites is associated with the abundance of band-tailed pigeons, and 3) relative density of band-tailed pigeons in the Pacific Northwest exhibits a latitudinal gradient with more birds counted near the middle of their breeding range. Use of mineral sites in Oregon by band-tailed pigeons was associated with both the amount of forest cover (or lack thereof), and the amount of land under either private ownership or under special management to preserve biodiversity. Higher probability of mineral site use was predicted with increasing forest cover and special status land, lower probability of use was predicted with increasing non-forested landcover and private land. Four hot springs in Oregon were known to have once been used by band-tailed pigeons by no longer are, no hot springs are known to be currently used by band-tailed. Title: Habitat characteristics associated with abundance of band-tailed pigeons and use of mineral sites in the Pacific Northwest Author: Overton, Cory T. Index counts for the Pacific Coast race of the band-tailed pigeon (Columba fasciata monilis) have declined by -2% per year since survey efforts began in the 1950's and 60's. Mineral sites, important resources with high ion concentrations, are regularly visited by band-tailed pigeons which nest in surrounding forest lands. I used both ad hoc measurements of mineral site characteristics and composition and configuration of habitat types adjacent to mineral sites to develop models predicting band-tailed pigeon abundance at mineral sites, in the Pacific Northwest. Band-tailed pigeons were counted weekly during the summers of 2001 and 2002 at 20 mineral sites. Since, many mineral sites have been abandoned by band-tailed pigeons, I tested for an association between land use types mineral site use by band-tailed pigeons using a database of 69 currently used and 20 historically used mineral sites in Oregon. Lastly, I investigated the association between the timing and duration of precipitation on index counts of band-tailed pigeons at 20 mineral sites. Abundance of band-tailed pigeons was positively associated with habitat dominance, (i.e. 1-Shannon's Evenness or homogeneity of landcover types) at a scale larger than band-tailed pigeon home range size and with distance to the nearest adjacent mineral site. Both a quadratic effect of latitude and use of an indicator variable for regional variation in abundance were also present in top ranked models. Both latitudinal effects predicted an increase in birds from central Oregon to southern Washington, then a decrease from central Washington to British Columbia. My findings suggest that: 1) large areas of homogeneous landcover are important for band-tailed pigeons, 2) distribution of mineral sites is associated with the abundance of band-tailed pigeons, and 3) relative density of band-tailed pigeons in the Pacific Northwest exhibits a latitudinal gradient with more birds counted near the middle of their breeding range. Use of mineral sites in Oregon by band-tailed pigeons was associated with both the amount of forest cover (or lack thereof), and the amount of land under either private ownership or under special management to preserve biodiversity. Higher probability of mineral site use was predicted with increasing forest cover and special status land, lower probability of use was predicted with increasing non-forested landcover and private land. Four hot springs in Oregon were known to have once been used by band-tailed pigeons by no longer are, no hot springs are known to be currently used by band-tailed. Close