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• 1. [Article] Combining and Aggregating Environmental Data for Status and Trend Assessments: Challenges and Approaches

  Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess ...

  Citation × Citation Citation Abstract Copy Title: Combining and Aggregating Environmental Data for Status and Trend Assessments: Challenges and Approaches Author: Maas-Hebner, Kathleen G., Harte, Michael, Molina, Nancy, Hughes, Robert M., Schreck, Carl B., Yeakley, J. Alan Year: 2015 Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess local-, regional-, and landscape-level environmental conditions, particularly status and trends, and to improve their ability to make short-and long-term management decisions. Status monitoring assesses the current condition of a population or environmental condition across an area. Monitoring for trends aims at monitoring changes in populations or environmental condition through time. We wrote this paper to inform agency and nongovernmental organization managers, analysts, and consultants regarding the kinds of environmental data that can be combined with suitable techniques and statistically aggregated for new assessments. By doing so, they can increase the (1) use of available data and (2) the validity and reliability of the assessments. Increased awareness of the difficulties inherent in combining and aggregating data for local-and regional-level analyses can increase the likelihood that future monitoring efforts will be modified and/or planned to accommodate data from multiple sources. Title: Combining and Aggregating Environmental Data for Status and Trend Assessments: Challenges and Approaches Author: Maas-Hebner, Kathleen G., Harte, Michael, Molina, Nancy, Hughes, Robert M., Schreck, Carl B., Yeakley, J. Alan Year: 2015 Increasingly, natural resource management agencies and nongovernmental organizations are sharing monitoring data across geographic and jurisdictional boundaries. Doing so improves their abilities to assess local-, regional-, and landscape-level environmental conditions, particularly status and trends, and to improve their ability to make short-and long-term management decisions. Status monitoring assesses the current condition of a population or environmental condition across an area. Monitoring for trends aims at monitoring changes in populations or environmental condition through time. We wrote this paper to inform agency and nongovernmental organization managers, analysts, and consultants regarding the kinds of environmental data that can be combined with suitable techniques and statistically aggregated for new assessments. By doing so, they can increase the (1) use of available data and (2) the validity and reliability of the assessments. Increased awareness of the difficulties inherent in combining and aggregating data for local-and regional-level analyses can increase the likelihood that future monitoring efforts will be modified and/or planned to accommodate data from multiple sources. Close

• 2. [Article] Effects of Water Development on Arid Land Freshwater Ecosystems

  This presentation focuses on the Columbia Basin Project

  Citation × Citation Citation Abstract Copy Title: Effects of Water Development on Arid Land Freshwater Ecosystems Author: Strecker, Angela L. Year: 2013 This presentation focuses on the Columbia Basin Project Title: Effects of Water Development on Arid Land Freshwater Ecosystems Author: Strecker, Angela L. Year: 2013 This presentation focuses on the Columbia Basin Project Close

• 3. [Article] Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon

  We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of ...

  Citation × Citation Citation Abstract Copy Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Title: Tree Cover Mapping for Assessing Greater Sage-Grouse Habitat in Eastern Oregon Author: Nielsen, Eric M., Noone, Matthew D. Year: 2014 We used a predictive model to map canopy cover of vegetation over seven feet in height ("tall woody vegetation") at 30-meter resolution over nearly 29 million acres within and adjacent to the range of the greater sage-grouse in Oregon (Figure 1). Texture measures computed at various resolutions from color-infrared aerial photography provided the main source of predictor data used to produce the map. Canopy cover was treated as a categorical variable using six cover classes: absent (cover class C0), present at less than 4% (C1), 4 – 10% (C2), 10 – 20% (C3), 20 – 50% (C4), and 50% and over (C5). The map is referenced to conditions in the years 2011 and 2012. Although the specific target of the mapping was western juniper (Juniperus occidentalis), our reference data did not permit separating juniper from other tall woody vegetation during the predictive modeling process. The majority of the tall woody vegetation within the project area is western juniper. However, in high elevation regions, riparian, wetland, and residential areas, other vegetation is occasionally represented. The methodology discussed here produces raw modeled data. It is recommended that prior to use in most applications this raw tree cover product be additionally filtered or masked to eliminate false detections which often occur adjacent to agricultural areas and roads. For species-specific applications, an additional modeling phase is necessary to either eliminate tree cover detections likely to be species other than the target, or to model species importance values associated with each tree occurrence. Close

• 4. [Article] Getting Salmon Back in Salmon Creek: Systematizing Comparative Water Quality Analysis for Targeted Restoration

  This presentation focuses on water quality restoration efforts in Salmon Creek

  Citation × Citation Citation Abstract Copy Title: Getting Salmon Back in Salmon Creek: Systematizing Comparative Water Quality Analysis for Targeted Restoration Author: Grabowski, Zbigniew J., Janjua, Sarah, Swamer, Michael, Chang, Heejun, Watson, Eric Year: 2013 This presentation focuses on water quality restoration efforts in Salmon Creek Title: Getting Salmon Back in Salmon Creek: Systematizing Comparative Water Quality Analysis for Targeted Restoration Author: Grabowski, Zbigniew J., Janjua, Sarah, Swamer, Michael, Chang, Heejun, Watson, Eric Year: 2013 This presentation focuses on water quality restoration efforts in Salmon Creek Close

• 5. [Article] The Interplay Between Landscape Structure and Biotic Interactions

  Landscape structure and biotic interactions are closely linked. We identify five aspects of landscape structure that contribute to the co-occurrence of species and restrict or enable different types of ...

  Citation × Citation Citation Abstract Copy Title: The Interplay Between Landscape Structure and Biotic Interactions Author: Zarnetske, Phoebe, Baiser, Benjamin, Strecker, Angela L., Record, Sydne, Belmaker, Jonathan, Tuanmu, Mao-Ning Year: 2017 Landscape structure and biotic interactions are closely linked. We identify five aspects of landscape structure that contribute to the co-occurrence of species and restrict or enable different types of biotic interactions: patch size and habitat amount, isolation of patches, barriers to dispersal and movement, persistence of landscape structure, and landscape complexity. In addition, these aspects of landscape structure influence the strength and outcome of biotic interactions. Whereas most research focuses on the effects of the abiotic environment on species and their biotic interactions, research on foundation species and ecosystem engineers demonstrates the important influence of biotic interactions on landscape structure itself, including effects on landscape complexity, extent of habitat, and the structure of landscape features. In this review, we describe ecological theories that lay the foundation for interplay between landscape structure and biotic interactions, and summarize these connections across an array of interacting species in freshwater, marine, and terrestrial systems. We end with suggestions for integrating the fields of landscape ecology and community ecology to better understand the connections between landscape structure and biotic interactions and better predict their dynamics in light of global change. Title: The Interplay Between Landscape Structure and Biotic Interactions Author: Zarnetske, Phoebe, Baiser, Benjamin, Strecker, Angela L., Record, Sydne, Belmaker, Jonathan, Tuanmu, Mao-Ning Year: 2017 Landscape structure and biotic interactions are closely linked. We identify five aspects of landscape structure that contribute to the co-occurrence of species and restrict or enable different types of biotic interactions: patch size and habitat amount, isolation of patches, barriers to dispersal and movement, persistence of landscape structure, and landscape complexity. In addition, these aspects of landscape structure influence the strength and outcome of biotic interactions. Whereas most research focuses on the effects of the abiotic environment on species and their biotic interactions, research on foundation species and ecosystem engineers demonstrates the important influence of biotic interactions on landscape structure itself, including effects on landscape complexity, extent of habitat, and the structure of landscape features. In this review, we describe ecological theories that lay the foundation for interplay between landscape structure and biotic interactions, and summarize these connections across an array of interacting species in freshwater, marine, and terrestrial systems. We end with suggestions for integrating the fields of landscape ecology and community ecology to better understand the connections between landscape structure and biotic interactions and better predict their dynamics in light of global change. Close

• 6. [Article] How 5-day Weather Patterns and Buoyancy Regulation Impact Algal Community Assemblage

  The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden ...

  Citation × Citation Citation Abstract Copy Title: How 5-day Weather Patterns and Buoyancy Regulation Impact Algal Community Assemblage Author: Brunkalla, Roberta Year: 2016 The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden changes in weather patterns can quickly impact lake thermal structure, which can rapidly influence the competition between buoyancy regulating cyanobacteria. By modeling competition, I hope to address how altered climate would shift the competitive advantage to toxin forming cyanobacteria. I plan on accomplishing this by coupling a one-dimensional hydrodynamic and algal competition model, with lake specific physiological parameters. A sensitivity test of the model could reveal dramatic shifts in algal competition under future climate change scenarios, which could have implications in how Upper Klamath Lake is managed and how restoration efforts are implemented. Title: How 5-day Weather Patterns and Buoyancy Regulation Impact Algal Community Assemblage Author: Brunkalla, Roberta Year: 2016 The purpose of this study is to model how 5-day weather patterns and algal buoyancy regulation influence the competition between two bloom forming cyanobacteria species in Upper Klamath Lake, Oregon. Sudden changes in weather patterns can quickly impact lake thermal structure, which can rapidly influence the competition between buoyancy regulating cyanobacteria. By modeling competition, I hope to address how altered climate would shift the competitive advantage to toxin forming cyanobacteria. I plan on accomplishing this by coupling a one-dimensional hydrodynamic and algal competition model, with lake specific physiological parameters. A sensitivity test of the model could reveal dramatic shifts in algal competition under future climate change scenarios, which could have implications in how Upper Klamath Lake is managed and how restoration efforts are implemented. Close

• 7. [Article] Climate Change and Land Management Impact Rangeland Condition and Sage-Grouse Habitat in Southeastern Oregon

  Contemporary pressures on sagebrush steppe from climate change, exotic species, wildfire, and land use change threaten rangeland species such as the greater sage-grouse (Centrocercus urophasianus). To ...

  Citation × Citation Citation Abstract Copy Title: Climate Change and Land Management Impact Rangeland Condition and Sage-Grouse Habitat in Southeastern Oregon Author: Creutzburg, Megan K., Henderson, Emilie B., Conklin, David R. Year: 2015 Contemporary pressures on sagebrush steppe from climate change, exotic species, wildfire, and land use change threaten rangeland species such as the greater sage-grouse (Centrocercus urophasianus). To effectively manage sagebrush steppe landscapes for long-term goals, managers need information about the potential impacts of climate change, disturbances, and management activities. We integrated information from a dynamic global vegetation model, a sage-grouse habitat climate envelope model, and a state-and-transition simulation model to project broad-scale vegetation dynamics and potential sage-grouse habitat across 23.5 million acres in southeastern Oregon. We evaluated four climate scenarios, including continuing current climate and three scenarios of global climate change, and three management scenarios, including no management, current management and a sage-grouse habitat restoration scenario. All climate change scenarios projected expansion of moist shrub steppe and contraction of dry shrub steppe, but climate scenarios varied widely in the projected extent of xeric shrub steppe, where hot, dry summer conditions are unfavorable for sage-grouse. Wildfire increased by 26% over the century under current climate due to exotic grass encroachment, and by two- to four-fold across all climate change scenarios as extreme fire years became more frequent. Exotic grasses rapidly expanded in all scenarios as large areas of the landscape initially in semi-degraded condition converted to exotic-dominated systems. Due to the combination of exotic grass invasion, juniper encroachment, and climatic unsuitability for sage-grouse, projected sage-grouse habitat declined in the first several decades, but increased in area under the three climate change scenarios later in the century, as moist shrub steppe increased and rangeland condition improved. Management activities in the model were generally unsuccessful in controlling exotic grass invasion but were effective in slowing woodland expansion. Current levels of restoration treatments were insufficient to prevent some juniper expansion, but increased treatment rates under the restoration scenario maintained juniper near initial levels in priority treatment areas. Our simulations indicate that climate change may have both positive and negative implications for maintaining sage-grouse habitat. Title: Climate Change and Land Management Impact Rangeland Condition and Sage-Grouse Habitat in Southeastern Oregon Author: Creutzburg, Megan K., Henderson, Emilie B., Conklin, David R. Year: 2015 Contemporary pressures on sagebrush steppe from climate change, exotic species, wildfire, and land use change threaten rangeland species such as the greater sage-grouse (Centrocercus urophasianus). To effectively manage sagebrush steppe landscapes for long-term goals, managers need information about the potential impacts of climate change, disturbances, and management activities. We integrated information from a dynamic global vegetation model, a sage-grouse habitat climate envelope model, and a state-and-transition simulation model to project broad-scale vegetation dynamics and potential sage-grouse habitat across 23.5 million acres in southeastern Oregon. We evaluated four climate scenarios, including continuing current climate and three scenarios of global climate change, and three management scenarios, including no management, current management and a sage-grouse habitat restoration scenario. All climate change scenarios projected expansion of moist shrub steppe and contraction of dry shrub steppe, but climate scenarios varied widely in the projected extent of xeric shrub steppe, where hot, dry summer conditions are unfavorable for sage-grouse. Wildfire increased by 26% over the century under current climate due to exotic grass encroachment, and by two- to four-fold across all climate change scenarios as extreme fire years became more frequent. Exotic grasses rapidly expanded in all scenarios as large areas of the landscape initially in semi-degraded condition converted to exotic-dominated systems. Due to the combination of exotic grass invasion, juniper encroachment, and climatic unsuitability for sage-grouse, projected sage-grouse habitat declined in the first several decades, but increased in area under the three climate change scenarios later in the century, as moist shrub steppe increased and rangeland condition improved. Management activities in the model were generally unsuccessful in controlling exotic grass invasion but were effective in slowing woodland expansion. Current levels of restoration treatments were insufficient to prevent some juniper expansion, but increased treatment rates under the restoration scenario maintained juniper near initial levels in priority treatment areas. Our simulations indicate that climate change may have both positive and negative implications for maintaining sage-grouse habitat. Close

• 8. [Article] GC/MS Analysis of Some Extractives from <i>Eichhornia crassipes</i>

  Eichhornia crassipes (water hyacinth) is an invasive weed that causes serious issues for rivers, lakes, and other reservoirs around the world, although it can be an excellent source for bioactive compounds ...

  Citation × Citation Citation Abstract Copy Title: GC/MS Analysis of Some Extractives from <i>Eichhornia crassipes</i> Author: Fileto-Pérez, Héctor A., Rutiaga-Quiñones, O. Miriam, Sytsma, Mark D., Lorne, Isabelle M., Luo, Wentai, Pankow, James F., Rutiaga-Quiñones, José G. Year: 2015 Eichhornia crassipes (water hyacinth) is an invasive weed that causes serious issues for rivers, lakes, and other reservoirs around the world, although it can be an excellent source for bioactive compounds such as phytosterols and some steroids found in many plants. In this study, water hyacinth samples from both Durango and Distrito Federal in Mexico were collected. Ascendant extracts (cyclohexane, hexane, acetone, and methanol) from their leaves, stems, and roots were analyzed. Using boron trifluoride (similar to 10% [similar to 1.3 M] in 1-butanol), all extracts were derivatized. Twenty-four derivatized samples were analyzed using a gas chromatography-mass spectrometry (GC/MS) method. Twenty carboxylic acids were found, as well as squalene, which was found in nine extract samples: four cyclohexane extracts, one hexane extract, three acetone extracts, and two methanol extracts. A compound not reported before, beta-stigmasterol, was identified on three hexane extracts, an acetone extract, and a methalonic extract. Spirostane in acetone root extract and cholestane in cyclohexane stem-leaf extract were also identified. Title: GC/MS Analysis of Some Extractives from <i>Eichhornia crassipes</i> Author: Fileto-Pérez, Héctor A., Rutiaga-Quiñones, O. Miriam, Sytsma, Mark D., Lorne, Isabelle M., Luo, Wentai, Pankow, James F., Rutiaga-Quiñones, José G. Year: 2015 Eichhornia crassipes (water hyacinth) is an invasive weed that causes serious issues for rivers, lakes, and other reservoirs around the world, although it can be an excellent source for bioactive compounds such as phytosterols and some steroids found in many plants. In this study, water hyacinth samples from both Durango and Distrito Federal in Mexico were collected. Ascendant extracts (cyclohexane, hexane, acetone, and methanol) from their leaves, stems, and roots were analyzed. Using boron trifluoride (similar to 10% [similar to 1.3 M] in 1-butanol), all extracts were derivatized. Twenty-four derivatized samples were analyzed using a gas chromatography-mass spectrometry (GC/MS) method. Twenty carboxylic acids were found, as well as squalene, which was found in nine extract samples: four cyclohexane extracts, one hexane extract, three acetone extracts, and two methanol extracts. A compound not reported before, beta-stigmasterol, was identified on three hexane extracts, an acetone extract, and a methalonic extract. Spirostane in acetone root extract and cholestane in cyclohexane stem-leaf extract were also identified. Close

• 9. [Article] Advancing Collaborative Solutions: Lessons from the Oregon Sage-Grouse Conservation Partnership (SageCon)

  The Sage-Grouse Conservation Partnership, also known as “SageCon,” was an unprecedented collaborative effort among federal, state, and private stakeholders to address landscape-scale threats to greater ...

  Citation × Citation Citation Abstract Copy Title: Advancing Collaborative Solutions: Lessons from the Oregon Sage-Grouse Conservation Partnership (SageCon) Author: Allen, Jennifer H., Odell, Turner, Babcock, Julia, Henrie, Charis Year: 2017 The Sage-Grouse Conservation Partnership, also known as “SageCon,” was an unprecedented collaborative effort among federal, state, and private stakeholders to address landscape-scale threats to greater sage-grouse while also acknowledging rural economic and community interests across eastern Oregon’s sagebrush range. A U.S. Fish and Wildlife Service (USFWS) preliminary finding that the sage-grouse warranted listing under the endangered species act, and a subsequent court settlement setting a deadline for a final listing decision were key drivers for SageCon participants to seek proactive solutions to protect the bird. A cadre of diverse Eastern Oregon stakeholders with experience working collaboratively on related public lands issues helped set the stage for the collaborative effort. As part of what the Department of the Interior described as a historic outcome, SageCon produced the 2015 Oregon Sage-Grouse Action Plan, which details voluntary and state-regulated conservation measures to preserve habitat and protect Oregon’s sage-grouse population from threats on public and private land. SageCon—as one part of a broader multi-state collaborative effort—led to a subsequent USFWS finding that the sage-grouse no longer warranted listing as endangered. In our study of this collaborative effort, we interviewed seventeen SageCon participants to identify collaborative approaches that may offer promise for other conservation and public policy efforts. We explored participant motivation for engaging in the process, collaborative process design, integration of science into the SageCon deliberations, and other experiences that interviewees found relevant. Title: Advancing Collaborative Solutions: Lessons from the Oregon Sage-Grouse Conservation Partnership (SageCon) Author: Allen, Jennifer H., Odell, Turner, Babcock, Julia, Henrie, Charis Year: 2017 The Sage-Grouse Conservation Partnership, also known as “SageCon,” was an unprecedented collaborative effort among federal, state, and private stakeholders to address landscape-scale threats to greater sage-grouse while also acknowledging rural economic and community interests across eastern Oregon’s sagebrush range. A U.S. Fish and Wildlife Service (USFWS) preliminary finding that the sage-grouse warranted listing under the endangered species act, and a subsequent court settlement setting a deadline for a final listing decision were key drivers for SageCon participants to seek proactive solutions to protect the bird. A cadre of diverse Eastern Oregon stakeholders with experience working collaboratively on related public lands issues helped set the stage for the collaborative effort. As part of what the Department of the Interior described as a historic outcome, SageCon produced the 2015 Oregon Sage-Grouse Action Plan, which details voluntary and state-regulated conservation measures to preserve habitat and protect Oregon’s sage-grouse population from threats on public and private land. SageCon—as one part of a broader multi-state collaborative effort—led to a subsequent USFWS finding that the sage-grouse no longer warranted listing as endangered. In our study of this collaborative effort, we interviewed seventeen SageCon participants to identify collaborative approaches that may offer promise for other conservation and public policy efforts. We explored participant motivation for engaging in the process, collaborative process design, integration of science into the SageCon deliberations, and other experiences that interviewees found relevant. Close

• 10. [Article] The Effects of Urbanization and Human Disturbance Upon Plant Community Structure and Bird Species Richness, Diversity, and Abundance in a Natural Forested Area (Forest Park) in Portland, Oregon

  The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Urbanization and Human Disturbance Upon Plant Community Structure and Bird Species Richness, Diversity, and Abundance in a Natural Forested Area (Forest Park) in Portland, Oregon Author: Broshot, Nancy Ellen Year: 1999 The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of plant and avian communities at 25 sites, 24 which were in Forest Park and surrounding areas and one which was in the Ancient Forest Preserve (old-growth stand) northwest of Forest Park. Data were analyzed using multiple regression, ANOV A, and Bonferonni/Dunn. Seven variables were selected representing different urbanization gradients. An additional covariable coded for the old-growth stand, allowing it to be used as a control. Many tree variables, especially those related to shade-tolerant species, were positively correlated with both the distance from downtown Portland and the number of houses in the surrounding area, and negatively correlated with the distance from the nearest forest edge; however, many shrub and herbaceous variables were negatively correlated with the distance from downtown Portland. Species diversity for herbaceous and shrub species was greater at more urban sites, but diversity of trees was lower at more urban sites. There were significantly more non-native species of plants in the city section. I found significantly fewer saplings and small trees, especially shade-tolerant species, in the section of Forest Park closest to downtown Portland, although tree mortality was positively correlated with distance from Portland. Summer bird data revealed significant increases in the abundances of urban and edge species at more urban sites, with concomitant reductions in forest species. There were significantly more ground gleaning birds and short distance migratory species. I also found a significantly greater abundance of birds in the old-growth stand during the winter. This increase was positively correlated with the depth of snow in the nearby Cascade Mountains. My results indicate that Forest Park is apparently progressing in a normal successional pattern with the exception of the city section. The reduction in shade tolerant saplings and small trees in the city section suggest that rate of succession has been slower at more urban sites. Avian data suggest that urbanization affects bird species abundance and guild composition in the more urban areas. Title: The Effects of Urbanization and Human Disturbance Upon Plant Community Structure and Bird Species Richness, Diversity, and Abundance in a Natural Forested Area (Forest Park) in Portland, Oregon Author: Broshot, Nancy Ellen Year: 1999 The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of plant and avian communities at 25 sites, 24 which were in Forest Park and surrounding areas and one which was in the Ancient Forest Preserve (old-growth stand) northwest of Forest Park. Data were analyzed using multiple regression, ANOV A, and Bonferonni/Dunn. Seven variables were selected representing different urbanization gradients. An additional covariable coded for the old-growth stand, allowing it to be used as a control. Many tree variables, especially those related to shade-tolerant species, were positively correlated with both the distance from downtown Portland and the number of houses in the surrounding area, and negatively correlated with the distance from the nearest forest edge; however, many shrub and herbaceous variables were negatively correlated with the distance from downtown Portland. Species diversity for herbaceous and shrub species was greater at more urban sites, but diversity of trees was lower at more urban sites. There were significantly more non-native species of plants in the city section. I found significantly fewer saplings and small trees, especially shade-tolerant species, in the section of Forest Park closest to downtown Portland, although tree mortality was positively correlated with distance from Portland. Summer bird data revealed significant increases in the abundances of urban and edge species at more urban sites, with concomitant reductions in forest species. There were significantly more ground gleaning birds and short distance migratory species. I also found a significantly greater abundance of birds in the old-growth stand during the winter. This increase was positively correlated with the depth of snow in the nearby Cascade Mountains. My results indicate that Forest Park is apparently progressing in a normal successional pattern with the exception of the city section. The reduction in shade tolerant saplings and small trees in the city section suggest that rate of succession has been slower at more urban sites. Avian data suggest that urbanization affects bird species abundance and guild composition in the more urban areas. Close