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• 211. [Article] Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes

  Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat ...

  Citation × Citation Citation Abstract Copy Title: Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes Author: Renfrew, Rosalind B., Hill, Jason M., Kim, Daniel H., Romanek, Christopher, Perlut, Noah G. Year: 2017 Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate breeding populations. We compared winter diet composition among 3 breeding populations of Bobolinks and during 3 stages of winter molt using stable carbon isotope ratios. We used mixing models to compare the ratio of carbon-12 to carbon-13 isotope (d13C value) in feathers—grown on the wintering grounds but collected from individuals (n ¼ 105) breeding in Vermont, Nebraska, and North Dakota, USA—to estimate diet during early, middle, and late winter molt. Across the 3 breeding populations, Bobolinks relied on C3 sources for nearly one-third of their diet during the winter molt. Isotope data from feathers collected while growing on the wintering grounds from birds in rice vs. non-rice regions supported our assumption that C3 signatures are primarily due to a rice diet. The proportion of rice consumed was highest during late molt, corresponding with a period of greater rice availability to Bobolinks. Our results demonstrate that rice was a substantial component of the diet throughout the winter molt and was most exploited prior to northbound migration. Research is needed on the potential trade-offs of feeding on abundant cultivated rice, including its nutritional value and associated risks and conflicts from foraging in an agricultural setting. Title: Winter Diet of Bobolink, a Long-Distance Migratory Grassland Bird, Inferred from Feather Isotopes Author: Renfrew, Rosalind B., Hill, Jason M., Kim, Daniel H., Romanek, Christopher, Perlut, Noah G. Year: 2017 Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate breeding populations. We compared winter diet composition among 3 breeding populations of Bobolinks and during 3 stages of winter molt using stable carbon isotope ratios. We used mixing models to compare the ratio of carbon-12 to carbon-13 isotope (d13C value) in feathers—grown on the wintering grounds but collected from individuals (n ¼ 105) breeding in Vermont, Nebraska, and North Dakota, USA—to estimate diet during early, middle, and late winter molt. Across the 3 breeding populations, Bobolinks relied on C3 sources for nearly one-third of their diet during the winter molt. Isotope data from feathers collected while growing on the wintering grounds from birds in rice vs. non-rice regions supported our assumption that C3 signatures are primarily due to a rice diet. The proportion of rice consumed was highest during late molt, corresponding with a period of greater rice availability to Bobolinks. Our results demonstrate that rice was a substantial component of the diet throughout the winter molt and was most exploited prior to northbound migration. Research is needed on the potential trade-offs of feeding on abundant cultivated rice, including its nutritional value and associated risks and conflicts from foraging in an agricultural setting. Close

• 212. [Article] Metagenomes from High-Temperature Chemotrophic Systems Reveal Geochemical Controls on Microbial Community Structure and Function

  The Yellowstone caldera contains the most numerous and diverse geothermal systems on Earth, yielding an extensive array of unique high-temperature environments that host a variety of deeply-rooted and ...

  Citation × Citation Citation Abstract Copy Title: Metagenomes from High-Temperature Chemotrophic Systems Reveal Geochemical Controls on Microbial Community Structure and Function Author: Inskeep, William P., Rusch, Douglas B., Jay, Zackary J., Herrgard, Markus J., Kozubal, Mark A., Richardson, Toby H., Macur, Richard E., Hamamura, Natsuko, Jennings, Ryan deM., Fouke, Bruce W., Reysenbach, Anna-Louise, Roberto, Frank, Young, Mark, Schwartz, Ariel, Boyd, Eric S., Badger, Jonathan H., Mathur, Eric J., Ortmann, Alice C., Bateson, Mary, Geesey, Gill Year: 2010 The Yellowstone caldera contains the most numerous and diverse geothermal systems on Earth, yielding an extensive array of unique high-temperature environments that host a variety of deeply-rooted and understudied Archaea, Bacteria and Eukarya. The combination of extreme temperature and chemical conditions encountered in geothermal environments often results in considerably less microbial diversity than other terrestrial habitats and offers a tremendous opportunity for studying the structure and function of indigenous microbial communities and for establishing linkages between putative metabolisms and element cycling. Metagenome sequence (14-15,000 Sanger reads per site) was obtained for five hightemperature (>65°C) chemotrophic microbial communities sampled from geothermal springs (or pools) in Yellowstone National Park (YNP) that exhibit a wide range in geochemistry including pH, dissolved sulfide, dissolved oxygen and ferrous iron. Metagenome data revealed significant differences in the predominant phyla associated with each of these geochemical environments. Novel members of the Sulfolobales are dominant in low pH environments, while other Crenarchaeota including distantly-related Thermoproteales and Desulfurococcales populations dominate in suboxic sulfidic sediments. Several novel archaeal groups are well represented in an acidic (pH 3) Fe-oxyhydroxide mat, where a higher O2 influx is accompanied with an increase in archaeal diversity. The presence or absence of genes and pathways important in S oxidation-reduction, H2-oxidation, and aerobic respiration (terminal oxidation) provide insight regarding the metabolic strategies of indigenous organisms present in geothermal systems. Multiple-pathway and protein-specific functional analysis of metagenome sequence data corroborated results from phylogenetic analyses and clearly demonstrate major differences in metabolic potential across sites. The distribution of functional genes involved in electron transport is consistent with the hypothesis that geochemical parameters (e.g., pH, sulfide, Fe, O2) control microbial community structure and function in YNP geothermal springs. Title: Metagenomes from High-Temperature Chemotrophic Systems Reveal Geochemical Controls on Microbial Community Structure and Function Author: Inskeep, William P., Rusch, Douglas B., Jay, Zackary J., Herrgard, Markus J., Kozubal, Mark A., Richardson, Toby H., Macur, Richard E., Hamamura, Natsuko, Jennings, Ryan deM., Fouke, Bruce W., Reysenbach, Anna-Louise, Roberto, Frank, Young, Mark, Schwartz, Ariel, Boyd, Eric S., Badger, Jonathan H., Mathur, Eric J., Ortmann, Alice C., Bateson, Mary, Geesey, Gill Year: 2010 The Yellowstone caldera contains the most numerous and diverse geothermal systems on Earth, yielding an extensive array of unique high-temperature environments that host a variety of deeply-rooted and understudied Archaea, Bacteria and Eukarya. The combination of extreme temperature and chemical conditions encountered in geothermal environments often results in considerably less microbial diversity than other terrestrial habitats and offers a tremendous opportunity for studying the structure and function of indigenous microbial communities and for establishing linkages between putative metabolisms and element cycling. Metagenome sequence (14-15,000 Sanger reads per site) was obtained for five hightemperature (>65°C) chemotrophic microbial communities sampled from geothermal springs (or pools) in Yellowstone National Park (YNP) that exhibit a wide range in geochemistry including pH, dissolved sulfide, dissolved oxygen and ferrous iron. Metagenome data revealed significant differences in the predominant phyla associated with each of these geochemical environments. Novel members of the Sulfolobales are dominant in low pH environments, while other Crenarchaeota including distantly-related Thermoproteales and Desulfurococcales populations dominate in suboxic sulfidic sediments. Several novel archaeal groups are well represented in an acidic (pH 3) Fe-oxyhydroxide mat, where a higher O2 influx is accompanied with an increase in archaeal diversity. The presence or absence of genes and pathways important in S oxidation-reduction, H2-oxidation, and aerobic respiration (terminal oxidation) provide insight regarding the metabolic strategies of indigenous organisms present in geothermal systems. Multiple-pathway and protein-specific functional analysis of metagenome sequence data corroborated results from phylogenetic analyses and clearly demonstrate major differences in metabolic potential across sites. The distribution of functional genes involved in electron transport is consistent with the hypothesis that geochemical parameters (e.g., pH, sulfide, Fe, O2) control microbial community structure and function in YNP geothermal springs. Close

• 213. [Article] Factors for Improved Fish Passage Waterway Construction

  Streambeds are important fish passageways in Oregon; they provide for the necessary habitats and spawning cycles of a healthy fish population. Oregon state law requires that hydraulic structures located ...

  Citation × Citation Citation Abstract Copy Title: Factors for Improved Fish Passage Waterway Construction Author: Sillars, David N., Moradkhani, Hamid, Tymvios, Nicholas, Smith, Trevor D. Year: 2011 Streambeds are important fish passageways in Oregon; they provide for the necessary habitats and spawning cycles of a healthy fish population. Oregon state law requires that hydraulic structures located in water properly provide fish passage. Increasingly stringent state and federal regulations apply to these fish passageways, and designers must become more cognizant of conditions over a range of flows to accommodate fish movement and avoid expensive structural failure of these passageways. Fish passage structures are built when roads cross streambeds and may include culverts, or bridges. When these structures are built, the streambeds are re-created using a technique called “roughened channels”. Roughened channels are man-made stream channels utilized for re-creating the hydraulics necessary for adequate stream passage, and this may include new constructions or retrofits of older, inadequate structures. Mixtures of materials are used to construct the bed of roughened channels, ranging from fines such as sand, silt and gravel to coarse elements like cobbles and boulders. Fines are a critical element in limiting permeability of the constructed bed thus keeping stream flow at the surface of the roughened channel during low flow periods. This report discusses work of a research project designed to discover factors that are key to successful long-term implementation of fish passageways, especially focused on the construction process. Areas of inquiry postulated in this study are that failures experienced in actual installations may be due to inadequate range and/or mix of soil and rock material gradation; unexpected water velocity, especially during high flows; inadequate mixing of rock and soil materials during construction; and inadequate compaction of rock and soil materials during construction. This report suggests that several factors may be especially important considerations in fish passage success. These factors are the relationship of downstream slope to structure slope, well-graded fine soil materials in the channel fill (improved by choice of fill source), and frequent site visits. Improving fish passages for cost-efficient fish movement is a priority for government agencies such as Oregon Department of Transportation (ODOT) and Oregon Transportation Research and Education Consortium (OTREC). Title: Factors for Improved Fish Passage Waterway Construction Author: Sillars, David N., Moradkhani, Hamid, Tymvios, Nicholas, Smith, Trevor D. Year: 2011 Streambeds are important fish passageways in Oregon; they provide for the necessary habitats and spawning cycles of a healthy fish population. Oregon state law requires that hydraulic structures located in water properly provide fish passage. Increasingly stringent state and federal regulations apply to these fish passageways, and designers must become more cognizant of conditions over a range of flows to accommodate fish movement and avoid expensive structural failure of these passageways. Fish passage structures are built when roads cross streambeds and may include culverts, or bridges. When these structures are built, the streambeds are re-created using a technique called “roughened channels”. Roughened channels are man-made stream channels utilized for re-creating the hydraulics necessary for adequate stream passage, and this may include new constructions or retrofits of older, inadequate structures. Mixtures of materials are used to construct the bed of roughened channels, ranging from fines such as sand, silt and gravel to coarse elements like cobbles and boulders. Fines are a critical element in limiting permeability of the constructed bed thus keeping stream flow at the surface of the roughened channel during low flow periods. This report discusses work of a research project designed to discover factors that are key to successful long-term implementation of fish passageways, especially focused on the construction process. Areas of inquiry postulated in this study are that failures experienced in actual installations may be due to inadequate range and/or mix of soil and rock material gradation; unexpected water velocity, especially during high flows; inadequate mixing of rock and soil materials during construction; and inadequate compaction of rock and soil materials during construction. This report suggests that several factors may be especially important considerations in fish passage success. These factors are the relationship of downstream slope to structure slope, well-graded fine soil materials in the channel fill (improved by choice of fill source), and frequent site visits. Improving fish passages for cost-efficient fish movement is a priority for government agencies such as Oregon Department of Transportation (ODOT) and Oregon Transportation Research and Education Consortium (OTREC). Close

• 214. [Article] Road Ecology Course and Seminar Series

  The American road network is a major economic investment that is a major organizing force for human activity. The road system has profoundly altered ecological processes and, as a result, it is also an ...

  Citation × Citation Citation Abstract Copy Title: Road Ecology Course and Seminar Series Author: Sytsma, Mark D. Year: 2008 The American road network is a major economic investment that is a major organizing force for human activity. The road system has profoundly altered ecological processes and, as a result, it is also an important organizing force for ecosystems. Understanding the ecological consequences of road system design and use is critical to effective engineering and management of road systems to minimize impacts. I propose a new course within Environmental Science and Resources at PSU that will expose upper division undergraduate and graduate students to the fundamental concepts of road ecology through discussion, guest speakers, and field trips. I propose a student-led discussion course focusing on the book Road Ecology, edited by Forman et al. This book provides an introduction to the basic concepts underlying road impacts on the environment. Students will be required to read the book; discussion of each chapter will be led by a student who will make a presentation on results of a search of the primary literature on the subject of each chapter. The classroom discussion will be supplemented with guest speakers that will bring real- world examples to the classroom. Potential topics for guest speakers include: impacts of highway runoff and roadside spraying on water quality, impacts of roads on erosional processes, impacts of culverts on anadromous fish passage, mitigation of habitat fragmentation and road impacts on animal movements, and role of maintenance activities in facilitating weed invasions. Invited speakers will also be requested to provide a departmental seminar to communicate road ecology principles to a wider audience of undergraduate and graduate students in Environmental Science and Resources. Field trips to observe road impacts and mitigation measures will add to students understanding of road ecology. We will schedule field trips to observe impacts as well as efforts to mitigate environmental effects of roads. Students performance will be evaluated by participation in class discussions and field trips, and a term paper. Undergraduates will be required to write a literature review on an aspect of road ecology of their choosing. Graduate students will be required to write a proposal to investigate some aspect of road ecology. Following completion of the course students will have a broad understanding of the environmental impacts of road systems on ecological processes and methods of mitigating impacts. Graduate students will have a research proposal that may be appropriate for submittal to OTREC for funding. Title: Road Ecology Course and Seminar Series Author: Sytsma, Mark D. Year: 2008 The American road network is a major economic investment that is a major organizing force for human activity. The road system has profoundly altered ecological processes and, as a result, it is also an important organizing force for ecosystems. Understanding the ecological consequences of road system design and use is critical to effective engineering and management of road systems to minimize impacts. I propose a new course within Environmental Science and Resources at PSU that will expose upper division undergraduate and graduate students to the fundamental concepts of road ecology through discussion, guest speakers, and field trips. I propose a student-led discussion course focusing on the book Road Ecology, edited by Forman et al. This book provides an introduction to the basic concepts underlying road impacts on the environment. Students will be required to read the book; discussion of each chapter will be led by a student who will make a presentation on results of a search of the primary literature on the subject of each chapter. The classroom discussion will be supplemented with guest speakers that will bring real- world examples to the classroom. Potential topics for guest speakers include: impacts of highway runoff and roadside spraying on water quality, impacts of roads on erosional processes, impacts of culverts on anadromous fish passage, mitigation of habitat fragmentation and road impacts on animal movements, and role of maintenance activities in facilitating weed invasions. Invited speakers will also be requested to provide a departmental seminar to communicate road ecology principles to a wider audience of undergraduate and graduate students in Environmental Science and Resources. Field trips to observe road impacts and mitigation measures will add to students understanding of road ecology. We will schedule field trips to observe impacts as well as efforts to mitigate environmental effects of roads. Students performance will be evaluated by participation in class discussions and field trips, and a term paper. Undergraduates will be required to write a literature review on an aspect of road ecology of their choosing. Graduate students will be required to write a proposal to investigate some aspect of road ecology. Following completion of the course students will have a broad understanding of the environmental impacts of road systems on ecological processes and methods of mitigating impacts. Graduate students will have a research proposal that may be appropriate for submittal to OTREC for funding. Close

• 215. [Article] Osmosis Alive – Algae Water Filtration System

  Goals: Our goals of this project was to: Obtain an energy efficient, self-sufficient system to help reduce waste and money, and reuse and recycle water. To have a successful, natural, and more self-sufficient ...

  Citation × Citation Citation Abstract Copy Title: Osmosis Alive – Algae Water Filtration System Author: Gurganus, Adrik, Soe, Htet Htet, Baird, Jonathan, Beckett, Liam, Vautravers, Nick, Swensen, Parker, Johnson, Tucker Year: 2015 Goals: Our goals of this project was to: Obtain an energy efficient, self-sufficient system to help reduce waste and money, and reuse and recycle water. To have a successful, natural, and more self-sufficient filtration system, using algae. To use algae and other plants as an efficient way to filter water. To create a water filtration system that is organic and would have 0 waste. To use the water in the best and most efficient way possible, and to reduce energy and coal/oil consumption (water turbine) To make our community cleaner and greener, and reduce carbon footprint, pollution, and environmental impact. When we started this project, our first thought was renewable energy. We wanted to create a self-sustaining urban habitat for Humans to live in. We eventually began to gravitate towards a more specific concept which would involve grey water treatment. While gray water is known to be used for in home appliances such as toilets, it's not really used to generate electricity. What we have created is a system that utilizes the kinetic energy of grey water to help power the system itself. The system includes both standard filters and a less common non-photosynthetic algae filter to allow better use of the recycled city rainwater. If one spends time in our fine city, they will certainly notice the many old buildings around Portland. Though, they have majesty and charm flowing out of the rafters, they are also often inefficient in many regards. The other thing they will likely notice is the consistent downpour Portland has during the winter months, and even an occasional trickle during the summer months. The Peaceful Penguins team also manages to be this observant. We saw in our tours that many of the greener buildings in Portland make use of grey water run offs, i.e. rain, and recycle it for use around the facility. We aim to truly re-envision the way we think about grey water and it’s recycling. Title: Osmosis Alive – Algae Water Filtration System Author: Gurganus, Adrik, Soe, Htet Htet, Baird, Jonathan, Beckett, Liam, Vautravers, Nick, Swensen, Parker, Johnson, Tucker Year: 2015 Goals: Our goals of this project was to: Obtain an energy efficient, self-sufficient system to help reduce waste and money, and reuse and recycle water. To have a successful, natural, and more self-sufficient filtration system, using algae. To use algae and other plants as an efficient way to filter water. To create a water filtration system that is organic and would have 0 waste. To use the water in the best and most efficient way possible, and to reduce energy and coal/oil consumption (water turbine) To make our community cleaner and greener, and reduce carbon footprint, pollution, and environmental impact. When we started this project, our first thought was renewable energy. We wanted to create a self-sustaining urban habitat for Humans to live in. We eventually began to gravitate towards a more specific concept which would involve grey water treatment. While gray water is known to be used for in home appliances such as toilets, it's not really used to generate electricity. What we have created is a system that utilizes the kinetic energy of grey water to help power the system itself. The system includes both standard filters and a less common non-photosynthetic algae filter to allow better use of the recycled city rainwater. If one spends time in our fine city, they will certainly notice the many old buildings around Portland. Though, they have majesty and charm flowing out of the rafters, they are also often inefficient in many regards. The other thing they will likely notice is the consistent downpour Portland has during the winter months, and even an occasional trickle during the summer months. The Peaceful Penguins team also manages to be this observant. We saw in our tours that many of the greener buildings in Portland make use of grey water run offs, i.e. rain, and recycle it for use around the facility. We aim to truly re-envision the way we think about grey water and it’s recycling. Close

• 216. [Article] The Impeccable Timing of the Apple Maggot Fly, <i>Rhagoletis pomonella</i> (Dipetera: Tephritidae), and its Implications for Ecological Speciation

  Speciation is the process by which life diversifies into discrete forms, and understanding its underlying mechanisms remains a primary focus for biologists. Increasingly, empirical studies are helping ...

  Citation × Citation Citation Abstract Copy Title: The Impeccable Timing of the Apple Maggot Fly, <i>Rhagoletis pomonella</i> (Dipetera: Tephritidae), and its Implications for Ecological Speciation Author: Mattsson, Monte Arthur Year: 2015 Speciation is the process by which life diversifies into discrete forms, and understanding its underlying mechanisms remains a primary focus for biologists. Increasingly, empirical studies are helping explain the role of ecology in generating biodiversity. Adaptive radiations are often propelled by selective fitness tradeoffs experienced by individuals that invade new habitats, resulting in reproductive isolation from ancestral conspecifics and potentially cladogenesis. Host specialist insects are among the most speciose organisms known and serve as highly useful models for studying adaptive radiations. We are just beginning to understand the pace and degree with which these insects diversify. The apple maggot, Rhagoletis pomonella, is a well-studied insect whose eastern and southern populations are models for ecological speciation. Recently (40–65 ya), the fly has invaded the Pacific Northwestern United States through human-transported apples infested with larvae. There, populations of R. pomonella have rapidly colonized two novel hawthorn hosts whose fruiting times bracket apple’s (early-season native Crataegus douglasii and introduced C. monogyna, which fruits late in the season). The recent introduction might initiate host shifts, providing opportunities to examine the pace and mechanistic means with which host races (an evolutionary stage preceding speciation) become established. Here, I demonstrate that host-associated populations at a site in southwest Washington are partially allochronically isolated from one another, and life cycles temporally match with natal host fruit ripening times in sympatry. If spatially widespread, these temporal barriers could result in reproductive isolation and possibly cladogenesis. Implications of these findings reach beyond academic import, as R. pomonella is expanding not only its host range, but its geographic range is encroaching upon central Washington, the site of a multi-billion dollar per year apple-growing industry. Title: The Impeccable Timing of the Apple Maggot Fly, <i>Rhagoletis pomonella</i> (Dipetera: Tephritidae), and its Implications for Ecological Speciation Author: Mattsson, Monte Arthur Year: 2015 Speciation is the process by which life diversifies into discrete forms, and understanding its underlying mechanisms remains a primary focus for biologists. Increasingly, empirical studies are helping explain the role of ecology in generating biodiversity. Adaptive radiations are often propelled by selective fitness tradeoffs experienced by individuals that invade new habitats, resulting in reproductive isolation from ancestral conspecifics and potentially cladogenesis. Host specialist insects are among the most speciose organisms known and serve as highly useful models for studying adaptive radiations. We are just beginning to understand the pace and degree with which these insects diversify. The apple maggot, Rhagoletis pomonella, is a well-studied insect whose eastern and southern populations are models for ecological speciation. Recently (40–65 ya), the fly has invaded the Pacific Northwestern United States through human-transported apples infested with larvae. There, populations of R. pomonella have rapidly colonized two novel hawthorn hosts whose fruiting times bracket apple’s (early-season native Crataegus douglasii and introduced C. monogyna, which fruits late in the season). The recent introduction might initiate host shifts, providing opportunities to examine the pace and mechanistic means with which host races (an evolutionary stage preceding speciation) become established. Here, I demonstrate that host-associated populations at a site in southwest Washington are partially allochronically isolated from one another, and life cycles temporally match with natal host fruit ripening times in sympatry. If spatially widespread, these temporal barriers could result in reproductive isolation and possibly cladogenesis. Implications of these findings reach beyond academic import, as R. pomonella is expanding not only its host range, but its geographic range is encroaching upon central Washington, the site of a multi-billion dollar per year apple-growing industry. Close

• 217. [Article] The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams

  Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial ...

  Citation × Citation Citation Abstract Copy Title: The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams Author: Hoy, Raymond S. Year: 2001 Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial space in the substratum, which may have adverse effects on stream biota. A field survey was conducted in Oregon urban and non-urban basins to investigate the relationship between fine sediments and stream macroinvertebrates. Physical, chemical, and biological data were collected from 59 stream sites in two urban and two rural streams. The stream sites fulfilled a continuous sediment gradient, which ranged from a low of 2% of fine sediment in the substrate to a high of 64% with an average of 22%. The % fines, in Clear Creek (rural basin) was significantly lower than in the urban basins (Johnson Creek and Tryon Creek) (p=0.005). Johnson Creek (mean=23%) had approximately three times more fine sediment than Clear Creek (mean=7%), while Tryon Creek (mean=32%) had nearly five times as much fine sediment as Clear Creek. EPT taxa richness was significantly higher in both rural streams than in both urban streams (p0.05). For example, regression analysis of EPT taxa richness vs. % fine sediments displayed a coefficient of determination (r2) value of 0.2. Other macro invertebrates metrics displayed similar patterns. The lack of significant correlations may be due to the cumulative effect of basin-wide "historical land use past". Past land use activity may have resulted in long-term reductions of sensitive taxa in the basin taxa pool and efforts to improve local habitats may not be quickly colonized by pollution sensitive taxa. Long-term degradation to the urban streams resulted in a relatively homogenous assemblage of macro invertebrates, which may have confounded the quantitative relationship between sediments and macroinvertebrates. This study suggests there is a clear difference between urban and non-urban streams in terms of macro invertebrates, which may be likely due to sediments, but the quantitative relationship between fine sediments and macro invertebrates is weak. Title: The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams Author: Hoy, Raymond S. Year: 2001 Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial space in the substratum, which may have adverse effects on stream biota. A field survey was conducted in Oregon urban and non-urban basins to investigate the relationship between fine sediments and stream macroinvertebrates. Physical, chemical, and biological data were collected from 59 stream sites in two urban and two rural streams. The stream sites fulfilled a continuous sediment gradient, which ranged from a low of 2% of fine sediment in the substrate to a high of 64% with an average of 22%. The % fines, in Clear Creek (rural basin) was significantly lower than in the urban basins (Johnson Creek and Tryon Creek) (p=0.005). Johnson Creek (mean=23%) had approximately three times more fine sediment than Clear Creek (mean=7%), while Tryon Creek (mean=32%) had nearly five times as much fine sediment as Clear Creek. EPT taxa richness was significantly higher in both rural streams than in both urban streams (p0.05). For example, regression analysis of EPT taxa richness vs. % fine sediments displayed a coefficient of determination (r2) value of 0.2. Other macro invertebrates metrics displayed similar patterns. The lack of significant correlations may be due to the cumulative effect of basin-wide "historical land use past". Past land use activity may have resulted in long-term reductions of sensitive taxa in the basin taxa pool and efforts to improve local habitats may not be quickly colonized by pollution sensitive taxa. Long-term degradation to the urban streams resulted in a relatively homogenous assemblage of macro invertebrates, which may have confounded the quantitative relationship between sediments and macroinvertebrates. This study suggests there is a clear difference between urban and non-urban streams in terms of macro invertebrates, which may be likely due to sediments, but the quantitative relationship between fine sediments and macro invertebrates is weak. Close

• 218. [Article] Community level impacts associated with the invasion of English ivy (Hedera spp.) in Forest Park: a look at the impacts of ivy on community composition and soil moisture.

  Invasive species degrade ecosystems by altering natural processes and decreasing the abundance and diversity of native flora. Communities with major fluctuations in resource supply allow invasive species ...

  Citation × Citation Citation Abstract Copy Title: Community level impacts associated with the invasion of English ivy (Hedera spp.) in Forest Park: a look at the impacts of ivy on community composition and soil moisture. Author: Copp, Sara Rose Year: 2014 Invasive species degrade ecosystems by altering natural processes and decreasing the abundance and diversity of native flora. Communities with major fluctuations in resource supply allow invasive species to exploit limiting resources making the community prone to invasion. In the Pacific Northwest, urban forests characterized with limited light and seasonally limited soil moisture are being dominated by nonnative English ivy (Hedera spp). Three observational studies were conducted in the Southern end of Forest Park within the Balch Creek Subwatershed in Portland, Oregon in order to understand 1) how English ivy changes over three growing seasons, 2) how the native understory composition responds to English ivy, 3) if the dominance of English ivy reduces soil moisture to neighboring plants, 4) how English ivy and two co-occurring native herbs (Hydrophyllum tenuipes and Vancouveria hexandra) physiologically respond to seasonal changes in soil moisture. Percent cover of the understory community was collected in both 2010 and 2013 growing seasons in 54 plots in order to understand the change in cover over time. Community response and the relationship with soil moisture was analyzed using percent cover of the understory community and associated environmental variables including soil moisture collected in 128 plots during the 2013 field season. Finally, 15 plots with co-occurring Hedera spp, H. tenuipes and V. hexandra were sampled for stomatal conductance, leaf water potential, and associated environmental variables. Results show ivy cover increases on average 14% between 2010 and 2013 while native understory cover increased on average < 1%. Once ivy forms dense cover over 44% there is a reduction of native richness, diversity and herb cover while also an increase in available soil moisture and deciduous canopy cover. There were disparate impacts to different functional groups and between species. As functional group, the herbaceous community was the most impacted by ivy invasion. The shrubs and fern community had a variable response to ivy invasion. Many of the fern and shrub species least impacted by ivy also had associations with high soil moisture and deciduous canopy cover. Finally, data suggests that ivy does not take advantage of seasonally limiting soil moisture to invade the understory community. This study indicates that English ivy is both efficient at water use and may have the ability to obtain water from distant locations throughout the forest. Once established, ivy has the ability to alter the community composition. Ivy removal and habitat restoration are essential in order to maintain and enhance biodiversity in Forest Park. Title: Community level impacts associated with the invasion of English ivy (Hedera spp.) in Forest Park: a look at the impacts of ivy on community composition and soil moisture. Author: Copp, Sara Rose Year: 2014 Invasive species degrade ecosystems by altering natural processes and decreasing the abundance and diversity of native flora. Communities with major fluctuations in resource supply allow invasive species to exploit limiting resources making the community prone to invasion. In the Pacific Northwest, urban forests characterized with limited light and seasonally limited soil moisture are being dominated by nonnative English ivy (Hedera spp). Three observational studies were conducted in the Southern end of Forest Park within the Balch Creek Subwatershed in Portland, Oregon in order to understand 1) how English ivy changes over three growing seasons, 2) how the native understory composition responds to English ivy, 3) if the dominance of English ivy reduces soil moisture to neighboring plants, 4) how English ivy and two co-occurring native herbs (Hydrophyllum tenuipes and Vancouveria hexandra) physiologically respond to seasonal changes in soil moisture. Percent cover of the understory community was collected in both 2010 and 2013 growing seasons in 54 plots in order to understand the change in cover over time. Community response and the relationship with soil moisture was analyzed using percent cover of the understory community and associated environmental variables including soil moisture collected in 128 plots during the 2013 field season. Finally, 15 plots with co-occurring Hedera spp, H. tenuipes and V. hexandra were sampled for stomatal conductance, leaf water potential, and associated environmental variables. Results show ivy cover increases on average 14% between 2010 and 2013 while native understory cover increased on average < 1%. Once ivy forms dense cover over 44% there is a reduction of native richness, diversity and herb cover while also an increase in available soil moisture and deciduous canopy cover. There were disparate impacts to different functional groups and between species. As functional group, the herbaceous community was the most impacted by ivy invasion. The shrubs and fern community had a variable response to ivy invasion. Many of the fern and shrub species least impacted by ivy also had associations with high soil moisture and deciduous canopy cover. Finally, data suggests that ivy does not take advantage of seasonally limiting soil moisture to invade the understory community. This study indicates that English ivy is both efficient at water use and may have the ability to obtain water from distant locations throughout the forest. Once established, ivy has the ability to alter the community composition. Ivy removal and habitat restoration are essential in order to maintain and enhance biodiversity in Forest Park. Close

• 219. [Article] Ecology of White-Cheeked Crested Gibbons in Laos

  The endangered white-cheeked crested gibbon (Nomascus leucogenys), native to Laos, Vietnam, and perhaps China, remains little known and highly threatened. I studied seasonal variation in the diet, activity ...

  Citation × Citation Citation Abstract Copy Title: Ecology of White-Cheeked Crested Gibbons in Laos Author: Ruppell, Julia Cleverly Year: 2013 The endangered white-cheeked crested gibbon (Nomascus leucogenys), native to Laos, Vietnam, and perhaps China, remains little known and highly threatened. I studied seasonal variation in the diet, activity budget, and ranging behavior of three groups of white-cheeked crested gibbons in Nam Kading National Protected Area, Bolikhamxay Province, Laos, over 12 months in wet seasonal evergreen forest. Crested gibbons (Nomascus spp.) are speculated to be more folivorous than other gibbons, but this has never been confirmed because of the paucity of fieldwork on the genus. I studied diet in relation to forest seasonality to determine the contribution of leaves to the diet over an annual cycle. Although leaves were the main dietary item throughout the year (53-85% of monthly diet), gibbons substantially increased their consumption of fruit during periods when it was most abundant in the forest. Because fruit is a calorically rich source of food, gibbons seek fruit when it is abundant and obtained easily. Young leaf consumption increased when they did not have access to fruit, indicating that their diet is flexible but strongly dependent on seasonal availability of resources. In addition, rainfall had a negative association with fruit abundance and fruit in diet. Activity budgets are an important aspect of a species' ecology because they are directly related to home range use, energy allocation, and diet, but they have never before been studied in gibbons (Nomascus spp.) of the rainy, mountainous, forests of Laos. Annually, the three groups that I studied spent nearly equal amounts of time resting (30%), feeding (33%), and traveling (35%), but only a small amount of time singing (2%). However, the proportion of time allocated to different activities showed significant seasonal variation associated with rainfall and diet, and correlated with home range use. Gibbons increased traveling time and decreased feeding time when they ate more fruit, and they decreased traveling time and increased feeding time when they ate more leaves. When the gibbons spent more of their time traveling, they also had longer day range lengths, and used a higher percentage of their total home range. Moreover, when rainfall was high, the gibbons decreased traveling time and increased time resting and feeding. Average home range size was 37.9 hectares and daily average distance over which the gibbons ranged over the 12 month study was 1.48 km per day. Differences existed among the three groups. Overall, white-cheeked crested gibbons have a home range similar in size or larger than frugivorous gibbons, and larger than the folivorous siamang. Ranging was highly seasonal with shorter day ranges during times of low fruit availability and consumption. During times of high fruit availability and low rainfall, the gibbons took on an energy maximizing strategy where they maintained large home ranges, traveled longer distances and consumed larger quantities of fruit. Gibbons and their habitat in Laos have faced continuous threats over the past 10 years because of large scale development projects and subsistence hunting. Given the highly threatened status of the species in Vietnam and China, the Lao population is certainly the world's largest and the best hope for conservation of behavioral, ecological, and genetic diversity. Resources for conserving species in the country are very limited, and wildlife populations are already greatly fragmented. I describe the current conservation issues and based on the dietary and ranging information that I collected, recommend important conservation measures to safeguard the remaining populations of endangered gibbons from extinction. Title: Ecology of White-Cheeked Crested Gibbons in Laos Author: Ruppell, Julia Cleverly Year: 2013 The endangered white-cheeked crested gibbon (Nomascus leucogenys), native to Laos, Vietnam, and perhaps China, remains little known and highly threatened. I studied seasonal variation in the diet, activity budget, and ranging behavior of three groups of white-cheeked crested gibbons in Nam Kading National Protected Area, Bolikhamxay Province, Laos, over 12 months in wet seasonal evergreen forest. Crested gibbons (Nomascus spp.) are speculated to be more folivorous than other gibbons, but this has never been confirmed because of the paucity of fieldwork on the genus. I studied diet in relation to forest seasonality to determine the contribution of leaves to the diet over an annual cycle. Although leaves were the main dietary item throughout the year (53-85% of monthly diet), gibbons substantially increased their consumption of fruit during periods when it was most abundant in the forest. Because fruit is a calorically rich source of food, gibbons seek fruit when it is abundant and obtained easily. Young leaf consumption increased when they did not have access to fruit, indicating that their diet is flexible but strongly dependent on seasonal availability of resources. In addition, rainfall had a negative association with fruit abundance and fruit in diet. Activity budgets are an important aspect of a species' ecology because they are directly related to home range use, energy allocation, and diet, but they have never before been studied in gibbons (Nomascus spp.) of the rainy, mountainous, forests of Laos. Annually, the three groups that I studied spent nearly equal amounts of time resting (30%), feeding (33%), and traveling (35%), but only a small amount of time singing (2%). However, the proportion of time allocated to different activities showed significant seasonal variation associated with rainfall and diet, and correlated with home range use. Gibbons increased traveling time and decreased feeding time when they ate more fruit, and they decreased traveling time and increased feeding time when they ate more leaves. When the gibbons spent more of their time traveling, they also had longer day range lengths, and used a higher percentage of their total home range. Moreover, when rainfall was high, the gibbons decreased traveling time and increased time resting and feeding. Average home range size was 37.9 hectares and daily average distance over which the gibbons ranged over the 12 month study was 1.48 km per day. Differences existed among the three groups. Overall, white-cheeked crested gibbons have a home range similar in size or larger than frugivorous gibbons, and larger than the folivorous siamang. Ranging was highly seasonal with shorter day ranges during times of low fruit availability and consumption. During times of high fruit availability and low rainfall, the gibbons took on an energy maximizing strategy where they maintained large home ranges, traveled longer distances and consumed larger quantities of fruit. Gibbons and their habitat in Laos have faced continuous threats over the past 10 years because of large scale development projects and subsistence hunting. Given the highly threatened status of the species in Vietnam and China, the Lao population is certainly the world's largest and the best hope for conservation of behavioral, ecological, and genetic diversity. Resources for conserving species in the country are very limited, and wildlife populations are already greatly fragmented. I describe the current conservation issues and based on the dietary and ranging information that I collected, recommend important conservation measures to safeguard the remaining populations of endangered gibbons from extinction. Close

• 220. [Article] Informal Trails and the Spread of Invasive Species in Urban Natural Areas: Spatial Analysis of Informal Trails and their Effects on Understory Plant Communities in Forest Park, Portland, Oregon

  The risk of spread and establishment of invasive species to interior habitat within urban parks is of great concern to park managers and ecologists. Informal trails as a vector for this transmission are ...

  Citation × Citation Citation Abstract Copy Title: Informal Trails and the Spread of Invasive Species in Urban Natural Areas: Spatial Analysis of Informal Trails and their Effects on Understory Plant Communities in Forest Park, Portland, Oregon Author: Van Winkle, Jill Elise Year: 2014 The risk of spread and establishment of invasive species to interior habitat within urban parks is of great concern to park managers and ecologists. Informal trails as a vector for this transmission are not well understood. To characterize effects of informal trails on understory plant communities, I conducted a study of the informal trail network in Forest Park, Portland, Oregon. The system of 382 informal trails was mapped and evaluated qualitatively, and from this population a systematic sample was selected for analysis. To identify hotspots of informal trail activity, showing the relationship of informal trails to formal trails, other park features, and trail use level, I evaluated all mapped trails using line density spatial analysis tools. To characterize understory communities, thirty transects were placed along informal trails, with paired transects along nearby formal trails for comparison. I measured percent cover by species for non-graminoid understory plants, and percent total plant cover at different structural layers, for quadrats at regular intervals from the trail edge. I calculated richness and Shannon-Weaver diversity for non-graminoid understory plants. For community analysis, species were grouped by dispersal strategy, native status, and growth form. Observations from system mapping suggest that "hidden" behaviors drive many informal trails: bathroom stops, party spots, waste dumping, and camps make up 28% of all informal trails. Trails to private property are few but represent over 29% of total trail length. Informal trail density is highest along Balch Creek. Hotspots of informal trail presence are associated with trailheads, trail intersections, and water access. Quadrats located within one meter of informal trails showed higher richness and diversity due to increased number of introduced and ruderal species. Formal trails exhibit these same patterns to a stronger degree and over a greater distance (two meters) from the trail edge. Distance from trail edge explained variation in plant communities when grouped by dispersal type, but not by growth form. This study shows that although informal trails are widely distributed throughout the park, they are concentrated in high use areas. The presence of informal trails leads to significant changes in Forest Park plant communities that favor invasive and ruderal species, but these effects appear limited to two meters from the trail edge. Title: Informal Trails and the Spread of Invasive Species in Urban Natural Areas: Spatial Analysis of Informal Trails and their Effects on Understory Plant Communities in Forest Park, Portland, Oregon Author: Van Winkle, Jill Elise Year: 2014 The risk of spread and establishment of invasive species to interior habitat within urban parks is of great concern to park managers and ecologists. Informal trails as a vector for this transmission are not well understood. To characterize effects of informal trails on understory plant communities, I conducted a study of the informal trail network in Forest Park, Portland, Oregon. The system of 382 informal trails was mapped and evaluated qualitatively, and from this population a systematic sample was selected for analysis. To identify hotspots of informal trail activity, showing the relationship of informal trails to formal trails, other park features, and trail use level, I evaluated all mapped trails using line density spatial analysis tools. To characterize understory communities, thirty transects were placed along informal trails, with paired transects along nearby formal trails for comparison. I measured percent cover by species for non-graminoid understory plants, and percent total plant cover at different structural layers, for quadrats at regular intervals from the trail edge. I calculated richness and Shannon-Weaver diversity for non-graminoid understory plants. For community analysis, species were grouped by dispersal strategy, native status, and growth form. Observations from system mapping suggest that "hidden" behaviors drive many informal trails: bathroom stops, party spots, waste dumping, and camps make up 28% of all informal trails. Trails to private property are few but represent over 29% of total trail length. Informal trail density is highest along Balch Creek. Hotspots of informal trail presence are associated with trailheads, trail intersections, and water access. Quadrats located within one meter of informal trails showed higher richness and diversity due to increased number of introduced and ruderal species. Formal trails exhibit these same patterns to a stronger degree and over a greater distance (two meters) from the trail edge. Distance from trail edge explained variation in plant communities when grouped by dispersal type, but not by growth form. This study shows that although informal trails are widely distributed throughout the park, they are concentrated in high use areas. The presence of informal trails leads to significant changes in Forest Park plant communities that favor invasive and ruderal species, but these effects appear limited to two meters from the trail edge. Close