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• 61. [Article] Comparative Characterization of Two Nearshore Rocky Reef Areas: A high-use recreational fishing reef vs. an unfished reef

  This project has provided the ODFW Marine Habitat Project with a unique opportunity to make a comparative examination of the habitats and fish communities of a heavily fished reef off of Siletz Bay, and ...

  Citation × Citation Citation Abstract Copy Title: Comparative Characterization of Two Nearshore Rocky Reef Areas: A high-use recreational fishing reef vs. an unfished reef Author: Merems, Arlene, Appy, Marcus, Romsos, Chris, Weeks, Hal, Fox, David, Amend, Mark This project has provided the ODFW Marine Habitat Project with a unique opportunity to make a comparative examination of the habitats and fish communities of a heavily fished reef off of Siletz Bay, and a nearly unfished reef off Cape Perpetua. There are over 17,000 angler trips for groundfish out of Depoe Bay annually, many choosing to fish Siletz Reef. In addition, numerous whale watching and sightseeing charter vessels operate in the vicinity of the reef. Cape Perpetua Reef consists of isolated patches of rock, and is too far from Newport (the nearest port) to receive much fishing effort. This examination of the influences of fishing pressure in nearshore rocky habitat complements, and is embedded in, a broader effort to understand the distribution and character of Oregon’s nearshore rocky reefs, and the species that are dependent upon them for habitat. The ODFW Marine Habitat Project has spent the last eight years working in cooperation with scientists and other resource agencies to develop methods for classifying and mapping nearshore rocky reefs habitats off Oregon. Because nearshore reefs are in state waters, Oregon is responsible for managing these living resources and habitats to sustain their long-term use and productivity. To date, eight reefs have been surveyed and mapped with sidescan and/or multibeam bathymetry at a resolution indicative of fish habitat. ODFW has also been developing non-extractive fish survey techniques to describe fish-habitat associations and estimate fish abundance at the habitat and reef scale. The importance of habitat to reef species cannot be over-stated and is now widely accepted in the scientific community and is the focus of major research efforts in other Pacific coastal states. Better understanding of the degree to which harvest influences relative and absolute abundance, combined with species-habitat relationships, is essential for resource managers to exercise their stewardship responsibilities to protect 5 essential habitat, develop population indices for species at risk, and maintain healthy and productive ecological systems. Title: Comparative Characterization of Two Nearshore Rocky Reef Areas: A high-use recreational fishing reef vs. an unfished reef Author: Merems, Arlene, Appy, Marcus, Romsos, Chris, Weeks, Hal, Fox, David, Amend, Mark This project has provided the ODFW Marine Habitat Project with a unique opportunity to make a comparative examination of the habitats and fish communities of a heavily fished reef off of Siletz Bay, and a nearly unfished reef off Cape Perpetua. There are over 17,000 angler trips for groundfish out of Depoe Bay annually, many choosing to fish Siletz Reef. In addition, numerous whale watching and sightseeing charter vessels operate in the vicinity of the reef. Cape Perpetua Reef consists of isolated patches of rock, and is too far from Newport (the nearest port) to receive much fishing effort. This examination of the influences of fishing pressure in nearshore rocky habitat complements, and is embedded in, a broader effort to understand the distribution and character of Oregon’s nearshore rocky reefs, and the species that are dependent upon them for habitat. The ODFW Marine Habitat Project has spent the last eight years working in cooperation with scientists and other resource agencies to develop methods for classifying and mapping nearshore rocky reefs habitats off Oregon. Because nearshore reefs are in state waters, Oregon is responsible for managing these living resources and habitats to sustain their long-term use and productivity. To date, eight reefs have been surveyed and mapped with sidescan and/or multibeam bathymetry at a resolution indicative of fish habitat. ODFW has also been developing non-extractive fish survey techniques to describe fish-habitat associations and estimate fish abundance at the habitat and reef scale. The importance of habitat to reef species cannot be over-stated and is now widely accepted in the scientific community and is the focus of major research efforts in other Pacific coastal states. Better understanding of the degree to which harvest influences relative and absolute abundance, combined with species-habitat relationships, is essential for resource managers to exercise their stewardship responsibilities to protect 5 essential habitat, develop population indices for species at risk, and maintain healthy and productive ecological systems. Close

• 62. [Article] Woody riparian species patterns along northeast Oregon mountainous streams and the relationship to riparian capability

  Woody riparian vegetation is an essential component of riparian ecosystems, responsible in part for the maintenance of functional ecological processes. The plant community composition and distribution ...

  Citation × Citation Citation Abstract Copy Title: Woody riparian species patterns along northeast Oregon mountainous streams and the relationship to riparian capability Author: Yancey, Jennifer M. Woody riparian vegetation is an essential component of riparian ecosystems, responsible in part for the maintenance of functional ecological processes. The plant community composition and distribution provide an indication of the underlying mosaic of environmental attributes and processes. Restoration and management of riparian communities have been hindered by the lack of measurable criteria for the assessment of a riparian systems modified by human imposed infrastructures. The woody vegetation community offered a quantifiable indicator of the underlying mosaic of environmental, physical, and hydrological attributes, while allowing the investigation of the concept of riparian potential versus riparian capability. The examination of riparian condition was measured through the determination of species-environmental relationships along three mountainous channels in northeast Oregon. The physical and environmental attributes of channel morphology, hydrology, understory community composition, surface particle characteristics, and microclimate variables were quantified and analyzed in relation to the woody vegetation composition and distribution across the three separate streams and within flood-frequency elevation zones. The second component of the study evaluated and described methods for quantifying the concept of riparian capability, based on the measured species-environmental relationships and channel morphology. The evaluation of condition was measured against the reference baseline of Rosgen hierarchical classification and regional hydraulic geometry curves. Multivariate analyses indicated that vegetation transects grouped by stream and vegetation belt transects weakly grouped by flood zone, based on the species composition quantified within the vegetation transects and flood zones. Secondly, channel geometry, canopy cover, air temperature, channel particle size, understory composition attributes, and flood zone distance were found to be overall gradients, which described the variation in species composition across the three streams in northeast Oregon. Direct individual species-environmental relationship conclusions were weak due to the close clustering of species and multiple physical and environmental gradients. Riparian condition at the Grande Ronde River and North Fork Catherine Creek was determined to be functioning at riparian capability. Channel geometry measurements at the two stream reaches aligned with Rosgen stream type criteria and regional hydrologic curves, while species composition represented characteristics of potential natural communities. Meadow Creek was concluded to have departed from the highest attainable condition, thus riparian condition was less than capability. The results suggested that woody riparian vegetation response was a function the physical sttributes: channel morphological widths, bankfull, floodprone, 25-year flood width, valley width, channel sinuosity, and channel slope. Environmental attributes, floodplain canopy cover, air temperature, and understory composition, were further factors that influenced the woody riparian vegetation community variation. The results also suggested species richness and diversity were associated with specific physical and environmental attributes. Finally, the results provided the determination of riparian capability along montane streams in northeast Oregon and criteria acceptable for the determination of riparian capability. These criteria included the physical channel measurements assessed against Rosgen hierarchiecal classification and regional channel geometry curves; and woody vegetation presence and distribution assessed against potential natural community plant associations. Further research should be done across a variety of riparian systems to determine both indicator species and reference values for the physical and environmental attributes that could be utilized for the assessment of riparian capability. Title: Woody riparian species patterns along northeast Oregon mountainous streams and the relationship to riparian capability Author: Yancey, Jennifer M. Woody riparian vegetation is an essential component of riparian ecosystems, responsible in part for the maintenance of functional ecological processes. The plant community composition and distribution provide an indication of the underlying mosaic of environmental attributes and processes. Restoration and management of riparian communities have been hindered by the lack of measurable criteria for the assessment of a riparian systems modified by human imposed infrastructures. The woody vegetation community offered a quantifiable indicator of the underlying mosaic of environmental, physical, and hydrological attributes, while allowing the investigation of the concept of riparian potential versus riparian capability. The examination of riparian condition was measured through the determination of species-environmental relationships along three mountainous channels in northeast Oregon. The physical and environmental attributes of channel morphology, hydrology, understory community composition, surface particle characteristics, and microclimate variables were quantified and analyzed in relation to the woody vegetation composition and distribution across the three separate streams and within flood-frequency elevation zones. The second component of the study evaluated and described methods for quantifying the concept of riparian capability, based on the measured species-environmental relationships and channel morphology. The evaluation of condition was measured against the reference baseline of Rosgen hierarchical classification and regional hydraulic geometry curves. Multivariate analyses indicated that vegetation transects grouped by stream and vegetation belt transects weakly grouped by flood zone, based on the species composition quantified within the vegetation transects and flood zones. Secondly, channel geometry, canopy cover, air temperature, channel particle size, understory composition attributes, and flood zone distance were found to be overall gradients, which described the variation in species composition across the three streams in northeast Oregon. Direct individual species-environmental relationship conclusions were weak due to the close clustering of species and multiple physical and environmental gradients. Riparian condition at the Grande Ronde River and North Fork Catherine Creek was determined to be functioning at riparian capability. Channel geometry measurements at the two stream reaches aligned with Rosgen stream type criteria and regional hydrologic curves, while species composition represented characteristics of potential natural communities. Meadow Creek was concluded to have departed from the highest attainable condition, thus riparian condition was less than capability. The results suggested that woody riparian vegetation response was a function the physical sttributes: channel morphological widths, bankfull, floodprone, 25-year flood width, valley width, channel sinuosity, and channel slope. Environmental attributes, floodplain canopy cover, air temperature, and understory composition, were further factors that influenced the woody riparian vegetation community variation. The results also suggested species richness and diversity were associated with specific physical and environmental attributes. Finally, the results provided the determination of riparian capability along montane streams in northeast Oregon and criteria acceptable for the determination of riparian capability. These criteria included the physical channel measurements assessed against Rosgen hierarchiecal classification and regional channel geometry curves; and woody vegetation presence and distribution assessed against potential natural community plant associations. Further research should be done across a variety of riparian systems to determine both indicator species and reference values for the physical and environmental attributes that could be utilized for the assessment of riparian capability. Close

• 63. [Article] Tradeoffs associated with managing forested landscapes for multiple-uses

  This study focuses on the tradeoffs that exist for managing forested landscapes for biodiversity and timber production. Tradeoff evaluation is important to natural resource managers so they can understand ...

  Citation × Citation Citation Abstract Copy Title: Tradeoffs associated with managing forested landscapes for multiple-uses Author: Lichtenstein, Mark E. This study focuses on the tradeoffs that exist for managing forested landscapes for biodiversity and timber production. Tradeoff evaluation is important to natural resource managers so they can understand the benefits and costs of alternative management prescriptions. The study examines three watersheds in the Oregon Coast Range and 166 terrestrial vertebrate species to determine the productive capacity of the site in terms of biodiversity and timber revenue. Two points are identified that maximize biodiversity and maximize timber revenue that serve as corner solutions for the production possibilities frontier for biodiversity and timber revenue. The frontier identifies all combinations of outputs that are equal in productive efficiency and the slope of the frontier identifies the marginal cost of biodiversity in terms of foregone timber revenue. A special case is then examined that reenacts the proposed management intentions of each ownership group in the study area. The special case model is used to examine the level of efficiency that exists with respect to the productive possibilities frontier. The results of the study indicate that there is a high level of inefficiency in the proposed management intentions of the various ownership groups. Higher levels of revenues can be achieved at the same level of biodiversity. Conversely more biodiversity can be produced at the same level of revenue. Marginal cost analysis also showed that biodiversity comes at an increasingly high cost at the extreme end of the productive capability of the study area. Results also indicate the species that are most affected by management activities are those that require large home ranges (> 200 acres) and species that are the most taxonomically unique. Title: Tradeoffs associated with managing forested landscapes for multiple-uses Author: Lichtenstein, Mark E. This study focuses on the tradeoffs that exist for managing forested landscapes for biodiversity and timber production. Tradeoff evaluation is important to natural resource managers so they can understand the benefits and costs of alternative management prescriptions. The study examines three watersheds in the Oregon Coast Range and 166 terrestrial vertebrate species to determine the productive capacity of the site in terms of biodiversity and timber revenue. Two points are identified that maximize biodiversity and maximize timber revenue that serve as corner solutions for the production possibilities frontier for biodiversity and timber revenue. The frontier identifies all combinations of outputs that are equal in productive efficiency and the slope of the frontier identifies the marginal cost of biodiversity in terms of foregone timber revenue. A special case is then examined that reenacts the proposed management intentions of each ownership group in the study area. The special case model is used to examine the level of efficiency that exists with respect to the productive possibilities frontier. The results of the study indicate that there is a high level of inefficiency in the proposed management intentions of the various ownership groups. Higher levels of revenues can be achieved at the same level of biodiversity. Conversely more biodiversity can be produced at the same level of revenue. Marginal cost analysis also showed that biodiversity comes at an increasingly high cost at the extreme end of the productive capability of the study area. Results also indicate the species that are most affected by management activities are those that require large home ranges (> 200 acres) and species that are the most taxonomically unique. Close

• 64. [Article] Hydrologic and vegetation responses associated with restoration of wetlands in the Willamette Valley, Oregon

  I examined hydrological and plant community changes associated with the implementation of a restoration management plan in two riparian meadows located within an agricultural landscape of the central Willamette ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic and vegetation responses associated with restoration of wetlands in the Willamette Valley, Oregon Author: Coleman, Gregory A. I examined hydrological and plant community changes associated with the implementation of a restoration management plan in two riparian meadows located within an agricultural landscape of the central Willamette Valley, Oregon. I established exclosure fencing (a form of passive restoration) in one agricultural field and established fencing and plugged a drainage ditch (active restoration) in a separate agricultural field. Permanent transects 15 m in length were established within two plant communities associated with hydrological regimes within these restored agricultural fields. Plant communities were classified as wetland meadow (inundated for more than 4 weeks/year) and mesic meadow (saturated within the upper 30 cm but not inundated) for at least 4 weeks/year. Four transects were randomly established within the wet meadow community and 6 transects were randomly situated within the mesic meadow community. Two shallow subsurface piezometers were installed to a depth of 1 m at 5 m and 10 m along each of these 15 m transects. Additionally, two shallow sub-surface piezometers were established at the outer perimeter of the agriculturally excluded fields. Shallow sub-surface and surface water table levels were measured at each piezometer after wetlands were inundated and continued until water table dropped below the piezometers (Dec. - June) for one pre-treatment and two post treatment years. The actively restored wet and mesic meadows demonstrated increased water table elevation and a decrease in water table fluctuation during both post treatment years. Increases in water table elevation were greatest in areas closest to active restoration but were significant up to 102 m. from restoration. Results indicate that filling drainage ditches induce hydrologic effects at great distances across floodplain soils. Plant community composition (species response) was quantified in both restored sites as well as the adjacent agriculturally managed (untreated) sites one year before treatment and two post-treatment years. I sampled two plant community types: wet meadow and mesic meadow. I calculated species richness and the relative abundance of wetland indicator species, nuisance weeds, and native plants. Nuisance weeds increased and native plant abundance decreased in agriculturally managed mesic meadows. Wetland plant species abundance tended to increase in agricultural sites with light grazing, and decreased in areas that were plowed and re-seeded. Native plants increased and nuisance weeds decreased in the actively restored mesic meadow. The passively restored mesic meadow exhibited no change in native plant abundance and decreases in all other categories. In the actively restored wetland there were increases in plant species richness and nuisance weed abundance with a decrease in native plant abundance. Agriculturally excluded wetlands dominated by Reed canary grass (Phalaris arundinacea) exhibited no changes for the entire study period. Results suggest that for the first few years following agricultural exclusion, nuisance weed species do not increase, but active restoration may result in increases (due to disturbance). Additionally, results indicate restored agricultural landscapes dominated by introduced grasses demonstrate minimal short-term plant community change unless initiated by intense land management practices (e g., plowing, re-seeding, or removal of dominant plant communities). Based upon results of this study, I conclude that restoration plans should repair damaged hydrological features before planting riparian plant species. Following this chronological sequence will minimize the potential destruction of planted communities by future shifts in water table elevation caused by hydrologic restoration. Furthermore, any active restoration that initiates a direct or indirect removal of the dominant plant community should be accompanied by aggressive plantings of desirable plant species and prolonged site maintenance. Title: Hydrologic and vegetation responses associated with restoration of wetlands in the Willamette Valley, Oregon Author: Coleman, Gregory A. I examined hydrological and plant community changes associated with the implementation of a restoration management plan in two riparian meadows located within an agricultural landscape of the central Willamette Valley, Oregon. I established exclosure fencing (a form of passive restoration) in one agricultural field and established fencing and plugged a drainage ditch (active restoration) in a separate agricultural field. Permanent transects 15 m in length were established within two plant communities associated with hydrological regimes within these restored agricultural fields. Plant communities were classified as wetland meadow (inundated for more than 4 weeks/year) and mesic meadow (saturated within the upper 30 cm but not inundated) for at least 4 weeks/year. Four transects were randomly established within the wet meadow community and 6 transects were randomly situated within the mesic meadow community. Two shallow subsurface piezometers were installed to a depth of 1 m at 5 m and 10 m along each of these 15 m transects. Additionally, two shallow sub-surface piezometers were established at the outer perimeter of the agriculturally excluded fields. Shallow sub-surface and surface water table levels were measured at each piezometer after wetlands were inundated and continued until water table dropped below the piezometers (Dec. - June) for one pre-treatment and two post treatment years. The actively restored wet and mesic meadows demonstrated increased water table elevation and a decrease in water table fluctuation during both post treatment years. Increases in water table elevation were greatest in areas closest to active restoration but were significant up to 102 m. from restoration. Results indicate that filling drainage ditches induce hydrologic effects at great distances across floodplain soils. Plant community composition (species response) was quantified in both restored sites as well as the adjacent agriculturally managed (untreated) sites one year before treatment and two post-treatment years. I sampled two plant community types: wet meadow and mesic meadow. I calculated species richness and the relative abundance of wetland indicator species, nuisance weeds, and native plants. Nuisance weeds increased and native plant abundance decreased in agriculturally managed mesic meadows. Wetland plant species abundance tended to increase in agricultural sites with light grazing, and decreased in areas that were plowed and re-seeded. Native plants increased and nuisance weeds decreased in the actively restored mesic meadow. The passively restored mesic meadow exhibited no change in native plant abundance and decreases in all other categories. In the actively restored wetland there were increases in plant species richness and nuisance weed abundance with a decrease in native plant abundance. Agriculturally excluded wetlands dominated by Reed canary grass (Phalaris arundinacea) exhibited no changes for the entire study period. Results suggest that for the first few years following agricultural exclusion, nuisance weed species do not increase, but active restoration may result in increases (due to disturbance). Additionally, results indicate restored agricultural landscapes dominated by introduced grasses demonstrate minimal short-term plant community change unless initiated by intense land management practices (e g., plowing, re-seeding, or removal of dominant plant communities). Based upon results of this study, I conclude that restoration plans should repair damaged hydrological features before planting riparian plant species. Following this chronological sequence will minimize the potential destruction of planted communities by future shifts in water table elevation caused by hydrologic restoration. Furthermore, any active restoration that initiates a direct or indirect removal of the dominant plant community should be accompanied by aggressive plantings of desirable plant species and prolonged site maintenance. Close

• 65. [Article] Ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae)

  A study consisting of three parts was undertaken to investigate how variation in species interactions, population genetic structure, epidemiological parameters, and plant breeding system may influence ...

  Citation × Citation Citation Abstract Copy Title: Ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae) Author: Campanella, Donald Michael A study consisting of three parts was undertaken to investigate how variation in species interactions, population genetic structure, epidemiological parameters, and plant breeding system may influence the ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae). Interactions between natural enemy species may modify their net effect on host plants, but little research has been done to examine how plant resistance influences species interactions in biological weed control. First, we performed common garden experiments with clonal accessions of C. juncea to compare a rust-susceptible weed biotype with a rust-resistant biotype, both of which are invasive in western North America. Inoculations with two biological control organisms, a rust fungus pathogen (Puccinia chondrillina) and an eriophyid gall mite (Eriophyes chondrillae), were applied separately and in combination to test if plant performance is modified by antagonistic or facilitative species interactions. We found no significant rust x mite interaction effects for several plant traits (shoot length, shoot dry biomass, fecundity, rosette growth, and rosette senescence), and therefore the two natural enemies appear to have independent and complementary effects on plant performance. However, rust inoculation reduced the total dry biomass of mite galls in the rust-susceptible biotype by indirect competition due to decreased growth of diseased shoots, but not in the rust-resistant biotype. Our results indicate that rust disease may have the potential to modify mite gall epidemiology and relative plant performance in mixed populations of resistant and susceptible C. juncea biotypes. In the second part of the study, a monitoring survey of C. juncea was conducted in southwest Oregon during 2006 to investigate natural associations in the distribution of damage caused by P. chondrillina, E. chondrillae, and the cecidomyiid gall midge Cystiphora schmidti. Mite galling was the most aggregated type of damage both within and among field sites. Analysis of an allometric relationship of shoot growth (biomass versus stem area) indicates that rust disease reduced C. juncea growth but only at high stand density, and in general rust disease was the most randomly distributed type of damage within sites. There was no evidence from the field survey to support a species interaction between the gall mite and the rust pathogen, but negative associations were detected between midge galling and the damage caused by both of the other natural enemies, which may indicate species interaction via rust and/or mite interference with C. schmidti oviposition. However, this potential antagonism was found only at high stand density with relatively high levels of damage caused by each natural enemy, and so the overall impact of biological control probably is not strongly diminished by enemy interference. The third part of the study was a mathematical model of inheritance and genetic equilibrium in meiotic diplospory, which is an unusual mechanism of gametophytic apomixis occurring in invasive populations of C. juncea and also in triploid dandelions (Taraxacum officinale). Crossing-over during prophase I of meiotic diplospory has the potential to generate genotypic diversity in apomictic lineages because it involves homologous recombination without fertilization ("subsexual reproduction"). I developed a stage-structured matrix model of inheritance in subsexual reproduction using a wide range of probabilities for recombination and mutation to assess the range of equilibrium conditions under which genotypic diversity is stable in obligately apomictic lines. The analysis supports predictions of genotypic diversity when rates of crossing-over and mutation are not highly imbalanced. Therefore subsexual reproduction remains mathematically plausible as a contributing factor to the quantitative variation in disease resistance and ecological traits of invasive C. juncea found in this study and others. Title: Ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae) Author: Campanella, Donald Michael A study consisting of three parts was undertaken to investigate how variation in species interactions, population genetic structure, epidemiological parameters, and plant breeding system may influence the ecology and biological control of an apomictic invasive plant, Chondrilla juncea (Asteraceae). Interactions between natural enemy species may modify their net effect on host plants, but little research has been done to examine how plant resistance influences species interactions in biological weed control. First, we performed common garden experiments with clonal accessions of C. juncea to compare a rust-susceptible weed biotype with a rust-resistant biotype, both of which are invasive in western North America. Inoculations with two biological control organisms, a rust fungus pathogen (Puccinia chondrillina) and an eriophyid gall mite (Eriophyes chondrillae), were applied separately and in combination to test if plant performance is modified by antagonistic or facilitative species interactions. We found no significant rust x mite interaction effects for several plant traits (shoot length, shoot dry biomass, fecundity, rosette growth, and rosette senescence), and therefore the two natural enemies appear to have independent and complementary effects on plant performance. However, rust inoculation reduced the total dry biomass of mite galls in the rust-susceptible biotype by indirect competition due to decreased growth of diseased shoots, but not in the rust-resistant biotype. Our results indicate that rust disease may have the potential to modify mite gall epidemiology and relative plant performance in mixed populations of resistant and susceptible C. juncea biotypes. In the second part of the study, a monitoring survey of C. juncea was conducted in southwest Oregon during 2006 to investigate natural associations in the distribution of damage caused by P. chondrillina, E. chondrillae, and the cecidomyiid gall midge Cystiphora schmidti. Mite galling was the most aggregated type of damage both within and among field sites. Analysis of an allometric relationship of shoot growth (biomass versus stem area) indicates that rust disease reduced C. juncea growth but only at high stand density, and in general rust disease was the most randomly distributed type of damage within sites. There was no evidence from the field survey to support a species interaction between the gall mite and the rust pathogen, but negative associations were detected between midge galling and the damage caused by both of the other natural enemies, which may indicate species interaction via rust and/or mite interference with C. schmidti oviposition. However, this potential antagonism was found only at high stand density with relatively high levels of damage caused by each natural enemy, and so the overall impact of biological control probably is not strongly diminished by enemy interference. The third part of the study was a mathematical model of inheritance and genetic equilibrium in meiotic diplospory, which is an unusual mechanism of gametophytic apomixis occurring in invasive populations of C. juncea and also in triploid dandelions (Taraxacum officinale). Crossing-over during prophase I of meiotic diplospory has the potential to generate genotypic diversity in apomictic lineages because it involves homologous recombination without fertilization ("subsexual reproduction"). I developed a stage-structured matrix model of inheritance in subsexual reproduction using a wide range of probabilities for recombination and mutation to assess the range of equilibrium conditions under which genotypic diversity is stable in obligately apomictic lines. The analysis supports predictions of genotypic diversity when rates of crossing-over and mutation are not highly imbalanced. Therefore subsexual reproduction remains mathematically plausible as a contributing factor to the quantitative variation in disease resistance and ecological traits of invasive C. juncea found in this study and others. Close

• 66. [Article] Trophic dynamics of marine nekton and zooplankton in the Northern California Current ecosystem

  The Northern California Current (NCC) ecosystem exhibits extreme seasonal, interannual and interdecadal shifts in the abiotic environment and shifts in primary and higher production. This variability is ...

  Citation × Citation Citation Abstract Copy Title: Trophic dynamics of marine nekton and zooplankton in the Northern California Current ecosystem Author: Miller, Todd William The Northern California Current (NCC) ecosystem exhibits extreme seasonal, interannual and interdecadal shifts in the abiotic environment and shifts in primary and higher production. This variability is also apparent in the spatial structure of the ecosystem with nearshore-shelf waters (<150 m isobath) being highly productive and having a different community structure relative to more offshore-slope (>150 m) waters. Very little is known of the trophic relationships between primary consumers and higher trophic levels within this system, and the potential influence of spatial gradients in productivity and community composition on trophic structure. This dissertation research covers several important aspects of trophic dynamics within the NCC ecosystem through the use of conventional dietary analysis and stable isotope analysis of multiple trophic levels. From June and August 2000 and 2002 cruises off the shelf-slope ecosystem from Northern California to central Oregon, I collected and analyzed the diets from 25 species of pelagic nekton (Chapter 2). Trophic groups were formed from agglomerative hierarchical cluster analysis of prey contribution to nekton diet, with cluster groups described by indicator species analysis. Seasonal, interannual and interdecadal comparisons in diet were examined for some nekton species. Results from general description of diets and cluster analysis showed clustering based primarily on prey of copepods, euphausiids, decapod larvae and larval-juvenile fishes, representing lower (copepods), middle (euphausiids and decapod larvae) and upper (larval-juvenile fishes) trophic groups, but that many species exhibited omnivory by feeding on prey several levels down the food web. Results from carbon and nitrogen stable isotope analysis (Chapter 3) support the general trophic structure observed through dietary analysis; that the copepod-euphausiid-larval/juvenile fish structure in the diets were generally observed in relative trophic position using δ15N. Carbon stable isotopes displayed signatures more indicative of onshore-offshore distribution of species (Chapter 4) with nearshore species of nekton and zooplankton being enriched in 13C relative to offshore. This provided an effective trophically-based delineation of the NCC pelagic food web. Although stable isotopes are effective tools for measuring relative trophic position and source production, the duration of time that stable isotopes are a measure of past trophic hsitory is not well known. To examine this, I conducted a laboratory-controlled experiment to examine the tissue-specific response of isotope δ15N to changes in isotopic signature of diet in an adult marine fish (Pacific herring, Clupea pallasi)(Chapter 5). To test which animal tissue was the most accurate measure of isotope shift I examined multiple tissues (eye, heart, liver, blood, and white muscle) and the importance of growth and metabolism in this shift. This study showed that (i) isotopic response of individual tissues following an isotopic shift in diet varied in both rate of change and fractionation level, (ii) most of this isotopic shift is due to growth, and (iii) white muscle and liver tissue appeared the most responsive to isotopic shift in diet, reaching isotopic equilibrium with diet in a matter of months (not years). The culmination of this dissertation in the context of trophic controls on the NCC ecosystem, and how they are different from other EBC systems are discussed in Chapter 6. Title: Trophic dynamics of marine nekton and zooplankton in the Northern California Current ecosystem Author: Miller, Todd William The Northern California Current (NCC) ecosystem exhibits extreme seasonal, interannual and interdecadal shifts in the abiotic environment and shifts in primary and higher production. This variability is also apparent in the spatial structure of the ecosystem with nearshore-shelf waters (<150 m isobath) being highly productive and having a different community structure relative to more offshore-slope (>150 m) waters. Very little is known of the trophic relationships between primary consumers and higher trophic levels within this system, and the potential influence of spatial gradients in productivity and community composition on trophic structure. This dissertation research covers several important aspects of trophic dynamics within the NCC ecosystem through the use of conventional dietary analysis and stable isotope analysis of multiple trophic levels. From June and August 2000 and 2002 cruises off the shelf-slope ecosystem from Northern California to central Oregon, I collected and analyzed the diets from 25 species of pelagic nekton (Chapter 2). Trophic groups were formed from agglomerative hierarchical cluster analysis of prey contribution to nekton diet, with cluster groups described by indicator species analysis. Seasonal, interannual and interdecadal comparisons in diet were examined for some nekton species. Results from general description of diets and cluster analysis showed clustering based primarily on prey of copepods, euphausiids, decapod larvae and larval-juvenile fishes, representing lower (copepods), middle (euphausiids and decapod larvae) and upper (larval-juvenile fishes) trophic groups, but that many species exhibited omnivory by feeding on prey several levels down the food web. Results from carbon and nitrogen stable isotope analysis (Chapter 3) support the general trophic structure observed through dietary analysis; that the copepod-euphausiid-larval/juvenile fish structure in the diets were generally observed in relative trophic position using δ15N. Carbon stable isotopes displayed signatures more indicative of onshore-offshore distribution of species (Chapter 4) with nearshore species of nekton and zooplankton being enriched in 13C relative to offshore. This provided an effective trophically-based delineation of the NCC pelagic food web. Although stable isotopes are effective tools for measuring relative trophic position and source production, the duration of time that stable isotopes are a measure of past trophic hsitory is not well known. To examine this, I conducted a laboratory-controlled experiment to examine the tissue-specific response of isotope δ15N to changes in isotopic signature of diet in an adult marine fish (Pacific herring, Clupea pallasi)(Chapter 5). To test which animal tissue was the most accurate measure of isotope shift I examined multiple tissues (eye, heart, liver, blood, and white muscle) and the importance of growth and metabolism in this shift. This study showed that (i) isotopic response of individual tissues following an isotopic shift in diet varied in both rate of change and fractionation level, (ii) most of this isotopic shift is due to growth, and (iii) white muscle and liver tissue appeared the most responsive to isotopic shift in diet, reaching isotopic equilibrium with diet in a matter of months (not years). The culmination of this dissertation in the context of trophic controls on the NCC ecosystem, and how they are different from other EBC systems are discussed in Chapter 6. Close

• 67. [Article] Reconnaissance botany of alpine ecosystems on Prince of Wales Island, southeast Alaska

  A study of the Prince of Wales Island alpine areas was undertaken to determine what species occur in the region and to describe plant communities making up the alpine vegetation. For one month in 1972, ...

  Citation × Citation Citation Abstract Copy Title: Reconnaissance botany of alpine ecosystems on Prince of Wales Island, southeast Alaska Author: Jaques, Dennis Randall A study of the Prince of Wales Island alpine areas was undertaken to determine what species occur in the region and to describe plant communities making up the alpine vegetation. For one month in 1972, specimens were collected and 78 micro-plots were analyzed for cover, frequency and constancy data. Three basic habitat types were discovered, with different associations being recognized on calcareous and noncalcareous substrates. Alpine vegetation patterns are formed in a physiographically unstable area. However, where conditions remain favorable for a long enough period of time, a climatic climax of Empetrum-heath vegetation develops. Elsewhere topographic climax vegetation exists. The region is thought to have maintained a flora of significant proportions at least since early post-Pleistocene time. The presence of many disjunct species indicates that floral elements may have survived Pleistocene ice advances in various refugial sites. The west coast of Prince of Wales Island appears to have served as a small migration center following Pleistocene ice recession. Title: Reconnaissance botany of alpine ecosystems on Prince of Wales Island, southeast Alaska Author: Jaques, Dennis Randall A study of the Prince of Wales Island alpine areas was undertaken to determine what species occur in the region and to describe plant communities making up the alpine vegetation. For one month in 1972, specimens were collected and 78 micro-plots were analyzed for cover, frequency and constancy data. Three basic habitat types were discovered, with different associations being recognized on calcareous and noncalcareous substrates. Alpine vegetation patterns are formed in a physiographically unstable area. However, where conditions remain favorable for a long enough period of time, a climatic climax of Empetrum-heath vegetation develops. Elsewhere topographic climax vegetation exists. The region is thought to have maintained a flora of significant proportions at least since early post-Pleistocene time. The presence of many disjunct species indicates that floral elements may have survived Pleistocene ice advances in various refugial sites. The west coast of Prince of Wales Island appears to have served as a small migration center following Pleistocene ice recession. Close

• 68. [Article] El Nino related variations in nutrient and chlorophyll distributions off Oregon

  The Oregon continental shelf waters are typically characterized by four to five major upwelling events that occur between May and October. The upwelled water is rich in nutrients, which fuels an increase ...

  Citation × Citation Citation Abstract Copy Title: El Nino related variations in nutrient and chlorophyll distributions off Oregon Author: Corwith, Holly L. The Oregon continental shelf waters are typically characterized by four to five major upwelling events that occur between May and October. The upwelled water is rich in nutrients, which fuels an increase in phytoplankton biomass. The onset of El Nino, however, can disrupt the normal physical processes along the Oregon coastline by decreasing upwelling, thereby potentially changing the distribution of nutrients and chlorophyll in this region. As part of the Eastern North Pacific GLOBEC program, we have examined the direct effect of El Nino on nutrient and chlorophyll distributions along the Oregon coast. We sampled chlorophyll and nutrients (phosphate, silicate, nitrate, nitrite, and ammonium) from September 1997 through July 1999 along 4 lines from 40°52.0' to 44°39.1'. Results showed that the shelf was nitrate limited, and chlorophyll concentrations were significantly lower off Newport during the El Nino summer. The percentage of large sized cells (> 10 gm) was decreased to 23% of the total population, as compared to 92% found during the more typical upwelling conditions in August. 1998, which indicates a species composition change occurred during the El Nino period. The slope and offshore waters were less affected by the El Nino conditions during the upwelling season. Title: El Nino related variations in nutrient and chlorophyll distributions off Oregon Author: Corwith, Holly L. The Oregon continental shelf waters are typically characterized by four to five major upwelling events that occur between May and October. The upwelled water is rich in nutrients, which fuels an increase in phytoplankton biomass. The onset of El Nino, however, can disrupt the normal physical processes along the Oregon coastline by decreasing upwelling, thereby potentially changing the distribution of nutrients and chlorophyll in this region. As part of the Eastern North Pacific GLOBEC program, we have examined the direct effect of El Nino on nutrient and chlorophyll distributions along the Oregon coast. We sampled chlorophyll and nutrients (phosphate, silicate, nitrate, nitrite, and ammonium) from September 1997 through July 1999 along 4 lines from 40°52.0' to 44°39.1'. Results showed that the shelf was nitrate limited, and chlorophyll concentrations were significantly lower off Newport during the El Nino summer. The percentage of large sized cells (> 10 gm) was decreased to 23% of the total population, as compared to 92% found during the more typical upwelling conditions in August. 1998, which indicates a species composition change occurred during the El Nino period. The slope and offshore waters were less affected by the El Nino conditions during the upwelling season. Close

• 69. [Article] Lidar-derived canopy architecture predicts brown creeper occupancy of two western coniferous forests

  This is the publisher’s final pdf. The published article is copyrighted by The Cooper Ornithological Society and can be found at: http://www.cooper.org/.

  Citation × Citation Citation Abstract Copy Title: Lidar-derived canopy architecture predicts brown creeper occupancy of two western coniferous forests Author: Vogeler, Jody C., Vierling, Lee A., Vierling, Kerri T., Hudak, Andrew T. This is the publisher’s final pdf. The published article is copyrighted by The Cooper Ornithological Society and can be found at: http://www.cooper.org/. Title: Lidar-derived canopy architecture predicts brown creeper occupancy of two western coniferous forests Author: Vogeler, Jody C., Vierling, Lee A., Vierling, Kerri T., Hudak, Andrew T. This is the publisher’s final pdf. The published article is copyrighted by The Cooper Ornithological Society and can be found at: http://www.cooper.org/. Close

• 70. [Article] Species associations and redundancy in relation to biological hotspots within the northern California Current ecosystem

  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 Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Species associations and redundancy in relation to biological hotspots within the northern California Current ecosystem Author: Reese, Douglas C., Brodeur, Richard D. 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 Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-marine-systems/. Title: Species associations and redundancy in relation to biological hotspots within the northern California Current ecosystem Author: Reese, Douglas C., Brodeur, Richard D. 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 Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-marine-systems/. Close

• 71. [Article] Effects of pesticides on amphibians with special reference to the pyrethroid insecticide, cypermethrin

  Pollution by pesticides is a ubiquitous concern for wildlife. The effects of pesticides are especially concerning in aquatic environments, which are particularly vulnerable as they have several exposure ...

  Citation × Citation Citation Abstract Copy Title: Effects of pesticides on amphibians with special reference to the pyrethroid insecticide, cypermethrin Author: Biga, Lindsay M. Pollution by pesticides is a ubiquitous concern for wildlife. The effects of pesticides are especially concerning in aquatic environments, which are particularly vulnerable as they have several exposure routes for the influx of chemicals. These effects are of particular concern as biodiversity loss reaches unprecedented rates. This includes recent declines of amphibian populations and loss of amphibian species. Pesticide exposure may contribute to some amphibian populations and extinctions. This dissertation explores the effects of pesticides on amphibians, with particular reference to the pyrethroid insecticide cypermethrin. I first synthesized acute toxicity data of pesticides for amphibians from the literature (Chapter 2). Using 96h LC50 values for amphibian larvae exposed to insecticides, herbicides, and fungicides, I determined that amphibian species cannot be systematically classified as sensitive or tolerant to pesticides. Rather, relative acute lethal toxicities varied among species and between chemicals and types of pesticides even within a species, indicating that no amphibian species from this analysis can represent anticipated toxic effects to all amphibians. I next examined the differences in sensitivity to cypermethrin among three developmental stages for three anuran (frog) species (Chapter 3). I experimentally exposed embryos, recently hatched larvae and larvae with limb buds to cypermethrin in the laboratory. Exposure to cypermethrin had lethal and sublethal effects on some species and stages, but not all. The Pacific treefrog (Pseudacris regilla) was the most sensitive species and the early larval stage was the most sensitive for these three species. Additionally, cypermethrin exposure induced abnormal behavior in response to prodding for some species and stages. These results indicate differences in sensitivity to cypermethrin among species of amphibians. To further understand differences in sensitivity to pesticides among amphibians, I compared how three populations of P. regilla responded to cypermethrin exposure (Chapter 4). I performed a time-to-death assay in the laboratory, exposing newly hatched larvae from each population to cypermethrin under identical conditions. All populations had high rates of mortality when exposed to cypermethrin compared to unexposed controls and populations varied in the time to death. Moreover, exposed individuals were smaller than unexposed controls. Interestingly, population sensitivity did not appear to be associated with proximity to agriculture, but rather with elevation gradient, indicating that an evolved tolerance to pesticide exposure is not the mechanism for the differences in sensitivity observed here. To investigate the effects of cypermethrin on amphibians within a community context, I studied exposure in mesocosms (Chapter 5). I set up semi-natural aquatic ponds in enclosures that contained zooplankton, phytoplankton, and periphyton along with amphibian larvae. I experimentally exposed these mesocosms to cypermethrin and measured the effects on the amphibians and the other members of the community. Cypermethrin affected the entire aquatic community, even at the lowest dose, indicating the direct and indirect deleterious effects of cypermethrin on both invertebrate and vertebrate species in an aquatic community. This dissertation provides needed data on the effects of the pyrethroid insecticide cypermethrin on amphibians and their communities. Understanding the toxicity of newer, commonly used pesticides to non-target organisms is important as conservation biologists and managers make efforts to combat future amphibian population declines which may be associated with chemicals in the environment. Title: Effects of pesticides on amphibians with special reference to the pyrethroid insecticide, cypermethrin Author: Biga, Lindsay M. Pollution by pesticides is a ubiquitous concern for wildlife. The effects of pesticides are especially concerning in aquatic environments, which are particularly vulnerable as they have several exposure routes for the influx of chemicals. These effects are of particular concern as biodiversity loss reaches unprecedented rates. This includes recent declines of amphibian populations and loss of amphibian species. Pesticide exposure may contribute to some amphibian populations and extinctions. This dissertation explores the effects of pesticides on amphibians, with particular reference to the pyrethroid insecticide cypermethrin. I first synthesized acute toxicity data of pesticides for amphibians from the literature (Chapter 2). Using 96h LC50 values for amphibian larvae exposed to insecticides, herbicides, and fungicides, I determined that amphibian species cannot be systematically classified as sensitive or tolerant to pesticides. Rather, relative acute lethal toxicities varied among species and between chemicals and types of pesticides even within a species, indicating that no amphibian species from this analysis can represent anticipated toxic effects to all amphibians. I next examined the differences in sensitivity to cypermethrin among three developmental stages for three anuran (frog) species (Chapter 3). I experimentally exposed embryos, recently hatched larvae and larvae with limb buds to cypermethrin in the laboratory. Exposure to cypermethrin had lethal and sublethal effects on some species and stages, but not all. The Pacific treefrog (Pseudacris regilla) was the most sensitive species and the early larval stage was the most sensitive for these three species. Additionally, cypermethrin exposure induced abnormal behavior in response to prodding for some species and stages. These results indicate differences in sensitivity to cypermethrin among species of amphibians. To further understand differences in sensitivity to pesticides among amphibians, I compared how three populations of P. regilla responded to cypermethrin exposure (Chapter 4). I performed a time-to-death assay in the laboratory, exposing newly hatched larvae from each population to cypermethrin under identical conditions. All populations had high rates of mortality when exposed to cypermethrin compared to unexposed controls and populations varied in the time to death. Moreover, exposed individuals were smaller than unexposed controls. Interestingly, population sensitivity did not appear to be associated with proximity to agriculture, but rather with elevation gradient, indicating that an evolved tolerance to pesticide exposure is not the mechanism for the differences in sensitivity observed here. To investigate the effects of cypermethrin on amphibians within a community context, I studied exposure in mesocosms (Chapter 5). I set up semi-natural aquatic ponds in enclosures that contained zooplankton, phytoplankton, and periphyton along with amphibian larvae. I experimentally exposed these mesocosms to cypermethrin and measured the effects on the amphibians and the other members of the community. Cypermethrin affected the entire aquatic community, even at the lowest dose, indicating the direct and indirect deleterious effects of cypermethrin on both invertebrate and vertebrate species in an aquatic community. This dissertation provides needed data on the effects of the pyrethroid insecticide cypermethrin on amphibians and their communities. Understanding the toxicity of newer, commonly used pesticides to non-target organisms is important as conservation biologists and managers make efforts to combat future amphibian population declines which may be associated with chemicals in the environment. Close

• 72. [Article] Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California

  Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional ...

  Citation × Citation Citation Abstract Copy Title: Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California Author: Moriarty, Katie M. Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order to maintain connectivity and viable populations, public land managers require science to inform how changes in structure affect the individual movements and thus population connectivity of sensitive species. I collected detailed movement data on Pacific martens (Martes caurina) in Lassen National Forest, California, during 2010-2013. Martens are small carnivores that are closely associated with old forest elements (e.g., large snags and logs). Marten populations rapidly decline with loss and fragmentation of forest cover. As such, martens are a U.S. Forest Service Management Indicator Species and a Species of Special Concern in the state of California. My goal was to understand martens' behavior in forest patches that were altered by thinning to remove ladder fuels-small diameter trees, understory vegetation, and branches near the ground. Such fuels treatments are increasingly prevalent on public lands, especially in dry forests, to reduce risk of high-severity and high-intensity fire. Although previous research suggested martens selection for dense forest and avoid gaps in forest cover, no information was available describing martens' use of simplified thinned patches. The objectives of my dissertation were to: (1) test whether marten movement and activity could accurately be measured using miniature GPS collars, and (2) evaluate marten use, selection, and behavior in patches that differed in structural complexity. Global positioning system (GPS) telemetry provides opportunities to collect detailed information from free-ranging animals with a high degree of precision and accuracy. Miniature GPS collars (42-60g) have only been available since 2009 for mammals and have not been consistently effective. Furthermore, all GPS units suffer from non-random data loss and location error, which is often exacerbated by dense vegetation. Given these constraints, it was questionable whether GPS collars would be an effective tool for studying martens. In Chapter 1, I evaluated how satellite data and environmental conditions affected performance of GPS units. I used a paired experimental design and programmed the GPS unit to retain or remove satellite data before attempting a location (fix). I found that short intervals between fix attempts significantly increased the likelihood of fix success. Locations estimated using at least 4 satellites were, on average, within 28 m of the actual location regardless of vegetation cover. Thus, location estimates at short intervals with >4 satellites were not typically biased by dense vegetation. Accurate fine-scale information on martens was necessary to quantify and interpret patch use and habitat selection. I evaluated martens’ use and behavior in three forest patch types that differed in structural complexity (complex, simple, and open). In Chapter 2, I quantified use patch use in two seasons–summer and winter. I used food-titration experiments to standardize motivation of martens to enter different patch types and compared these short-term incentivized experiments with year-round observational telemetry data (GPS and very high frequency telemetry). Martens selected complex patches and avoided both simple patches and openings, but not equivalently–openings were strongly avoided. With baited incentive, martens were more likely to enter simple patches and openings during winter, when deep snow was present. Because marten patch use differed during winter, I concluded that researchers should use caution when using seasonally collected data to create year-round habitat models. Overall, movement was most limited during summer when predation risk likely deterred martens from moving through simple patches and openings. In Chapter 3, I quantified habitat selection and marten behavior using fine-scale movement data. I evaluated movement-based habitat selection at two scales: (1) selection of home ranges within landscapes and (2) selection of patches within the home ranges. I characterized marten movement patterns and tested whether variance, speed, and sinuosity of movements differed by patch, sex, and season. Martens selected home ranges with fewer openings than available in the landscape, and selected complex patches over simple patches and openings within their home range. On average, martens moved approximately 7 km per day and greater than 1 km per hour – which is notably high for a 600-1000g mammal. Martens moved more slowly, consistently, and sinuously in complex patches. In openings, martens traveled linearly with greater variance in their speed. In simple patches, movement generally was linear and rapid with some variation. I hypothesized that martens used complex patches for foraging and acquisition of resources, traveled through simple patches with the potential for infrequent foraging bouts, and very infrequently crossed openings. Although I found some differences in movement behavior between sexes and seasons, behavior was generally consistent for both sexes in different patch types. I provide general conclusions in Chapter 4 and discuss considerations for future research and management. Title: Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California Author: Moriarty, Katie M. Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order to maintain connectivity and viable populations, public land managers require science to inform how changes in structure affect the individual movements and thus population connectivity of sensitive species. I collected detailed movement data on Pacific martens (Martes caurina) in Lassen National Forest, California, during 2010-2013. Martens are small carnivores that are closely associated with old forest elements (e.g., large snags and logs). Marten populations rapidly decline with loss and fragmentation of forest cover. As such, martens are a U.S. Forest Service Management Indicator Species and a Species of Special Concern in the state of California. My goal was to understand martens' behavior in forest patches that were altered by thinning to remove ladder fuels-small diameter trees, understory vegetation, and branches near the ground. Such fuels treatments are increasingly prevalent on public lands, especially in dry forests, to reduce risk of high-severity and high-intensity fire. Although previous research suggested martens selection for dense forest and avoid gaps in forest cover, no information was available describing martens' use of simplified thinned patches. The objectives of my dissertation were to: (1) test whether marten movement and activity could accurately be measured using miniature GPS collars, and (2) evaluate marten use, selection, and behavior in patches that differed in structural complexity. Global positioning system (GPS) telemetry provides opportunities to collect detailed information from free-ranging animals with a high degree of precision and accuracy. Miniature GPS collars (42-60g) have only been available since 2009 for mammals and have not been consistently effective. Furthermore, all GPS units suffer from non-random data loss and location error, which is often exacerbated by dense vegetation. Given these constraints, it was questionable whether GPS collars would be an effective tool for studying martens. In Chapter 1, I evaluated how satellite data and environmental conditions affected performance of GPS units. I used a paired experimental design and programmed the GPS unit to retain or remove satellite data before attempting a location (fix). I found that short intervals between fix attempts significantly increased the likelihood of fix success. Locations estimated using at least 4 satellites were, on average, within 28 m of the actual location regardless of vegetation cover. Thus, location estimates at short intervals with >4 satellites were not typically biased by dense vegetation. Accurate fine-scale information on martens was necessary to quantify and interpret patch use and habitat selection. I evaluated martens’ use and behavior in three forest patch types that differed in structural complexity (complex, simple, and open). In Chapter 2, I quantified use patch use in two seasons–summer and winter. I used food-titration experiments to standardize motivation of martens to enter different patch types and compared these short-term incentivized experiments with year-round observational telemetry data (GPS and very high frequency telemetry). Martens selected complex patches and avoided both simple patches and openings, but not equivalently–openings were strongly avoided. With baited incentive, martens were more likely to enter simple patches and openings during winter, when deep snow was present. Because marten patch use differed during winter, I concluded that researchers should use caution when using seasonally collected data to create year-round habitat models. Overall, movement was most limited during summer when predation risk likely deterred martens from moving through simple patches and openings. In Chapter 3, I quantified habitat selection and marten behavior using fine-scale movement data. I evaluated movement-based habitat selection at two scales: (1) selection of home ranges within landscapes and (2) selection of patches within the home ranges. I characterized marten movement patterns and tested whether variance, speed, and sinuosity of movements differed by patch, sex, and season. Martens selected home ranges with fewer openings than available in the landscape, and selected complex patches over simple patches and openings within their home range. On average, martens moved approximately 7 km per day and greater than 1 km per hour – which is notably high for a 600-1000g mammal. Martens moved more slowly, consistently, and sinuously in complex patches. In openings, martens traveled linearly with greater variance in their speed. In simple patches, movement generally was linear and rapid with some variation. I hypothesized that martens used complex patches for foraging and acquisition of resources, traveled through simple patches with the potential for infrequent foraging bouts, and very infrequently crossed openings. Although I found some differences in movement behavior between sexes and seasons, behavior was generally consistent for both sexes in different patch types. I provide general conclusions in Chapter 4 and discuss considerations for future research and management. Close

• 73. [Article] Species Diversification in Aquaculture: a Global Assessment

  Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, ...

  Citation × Citation Citation Abstract Copy Title: Species Diversification in Aquaculture: a Global Assessment Author: Zhou, Xiaowei, Yan, Xue, Cai, Junning Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Title: Species Diversification in Aquaculture: a Global Assessment Author: Zhou, Xiaowei, Yan, Xue, Cai, Junning Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Close

• 74. [Article] Geographic variation in Dunn's salamander Plethodon dunni Bishop (Amphibia:Caudata:Plethodontidae)

  Life history attributes and apparent distributional patterns suggest that Plethodon dunni exists as small, semi-isolated populations throughout its range. Isozyme and morphological variation in this species ...

  Citation × Citation Citation Abstract Copy Title: Geographic variation in Dunn's salamander Plethodon dunni Bishop (Amphibia:Caudata:Plethodontidae) Author: Hanlin, Hugh Grady Life history attributes and apparent distributional patterns suggest that Plethodon dunni exists as small, semi-isolated populations throughout its range. Isozyme and morphological variation in this species was examined to determine any possible geographic trends. Starch gel electrophoresis was utilized to examine genetic variation at 24 isozyme loci in 287 individuals from 12 populations to determine the genetic structure of populations of this species. Low total genetic variability was observed. However, this variability is partitioned into relatively low genetic heterozygosity within populations and proportionally high diversity between populations. It is concluded that this geographically restricted species is characterized by small local populations with little gene flow. Comparisons with previous reports of Plethodon species indicate that the high genetic divergence between local populations is apparently general for species in this genus. There is marked reduction in heterozygosity with peripheral populations of P. dunni, which may result from the reduction in genetic exchange from surrounding populations in peripheral as ccmpared to central populations. No indication of additional structural genes associated with the increased DNA in P. dunni was found. Morphological variation in 10 populations was examined via stepwise discriminant analyses. Considerable overlap of individuals' canonical scores and only moderately correct classifications into groups indicate that phenotypic expression in this species is exceedingly similar. However, on a fine scale there is significant heterogeneity between all populations. Generalized distance values (D²) between the P. dunni populations are high, particularly when compared to those of Aneides ferreus, a wider-ranging, more ubiquitous sympatric species. Clinal variation in morphological divergence was observed and was highly correlated with a similar cline in allele frequencies of EST-2. It is concluded that the phenotypic structuring of populations of P. dunni is consistent with the structuring observed via electrophoresis and that this species is characterized by small, localized populations throughout its range. Title: Geographic variation in Dunn's salamander Plethodon dunni Bishop (Amphibia:Caudata:Plethodontidae) Author: Hanlin, Hugh Grady Life history attributes and apparent distributional patterns suggest that Plethodon dunni exists as small, semi-isolated populations throughout its range. Isozyme and morphological variation in this species was examined to determine any possible geographic trends. Starch gel electrophoresis was utilized to examine genetic variation at 24 isozyme loci in 287 individuals from 12 populations to determine the genetic structure of populations of this species. Low total genetic variability was observed. However, this variability is partitioned into relatively low genetic heterozygosity within populations and proportionally high diversity between populations. It is concluded that this geographically restricted species is characterized by small local populations with little gene flow. Comparisons with previous reports of Plethodon species indicate that the high genetic divergence between local populations is apparently general for species in this genus. There is marked reduction in heterozygosity with peripheral populations of P. dunni, which may result from the reduction in genetic exchange from surrounding populations in peripheral as ccmpared to central populations. No indication of additional structural genes associated with the increased DNA in P. dunni was found. Morphological variation in 10 populations was examined via stepwise discriminant analyses. Considerable overlap of individuals' canonical scores and only moderately correct classifications into groups indicate that phenotypic expression in this species is exceedingly similar. However, on a fine scale there is significant heterogeneity between all populations. Generalized distance values (D²) between the P. dunni populations are high, particularly when compared to those of Aneides ferreus, a wider-ranging, more ubiquitous sympatric species. Clinal variation in morphological divergence was observed and was highly correlated with a similar cline in allele frequencies of EST-2. It is concluded that the phenotypic structuring of populations of P. dunni is consistent with the structuring observed via electrophoresis and that this species is characterized by small, localized populations throughout its range. Close

• 75. [Article] Age, growth and maturity of the longnose skate (Raja rhina) for the U.S. west coast and sensitivity to fishing impacts

  In the past, sharks, skates and ray species have mainly occurred in incidental fisheries. Now they are increasingly being directly targeted due to the depleted status of traditionally targeted species. ...

  Citation × Citation Citation Abstract Copy Title: Age, growth and maturity of the longnose skate (Raja rhina) for the U.S. west coast and sensitivity to fishing impacts Author: Thompson, Josie E. In the past, sharks, skates and ray species have mainly occurred in incidental fisheries. Now they are increasingly being directly targeted due to the depleted status of traditionally targeted species. The life history characteristics of many elasmobranch species make them more sensitive to high rates of fishing mortality. The combination of these factors has resulted in the known local depletion of several elasmobranch species; including the barndoor skate, Raja laevis, of the Northwest Atlantic and the common skate, Raja batis, of Irish Sea. The longnose skate, Raja rhina, occurs commonly as incidental catch in trawl fisheries off the coast of California, Oregon and Washington. Commercial landings of skates, including R. rhina, have increased dramatically along the U.S. West coast. The objectives of this study have been to calculate accurate growth and maturity parameters for Raja rhina in order that the vulnerability of this species to fishing mortality can be assessed. The slow growth rates (k=0.04 to 0.06) and late ages-at-50% maturity (11 to 16 years with maximum ages between 15 and 22 years, depending on sex and region) which were calculated indicate that this species may be at great risk of depletion in the future. Survey biomass trends indicate that R. rhina populations have remained stable over the past twenty years. However, the possibility that biomass levels in the distant past were much higher than they are at present cannot be ruled out. It is recommended that the collection of fishery-dependent data for this species and other skate species begins immediately. This information, along with the results found in this are needed for a proper assessment for Raja rhina, so that the effects of current fishing pressures can be evaluated and regulated appropriately. Title: Age, growth and maturity of the longnose skate (Raja rhina) for the U.S. west coast and sensitivity to fishing impacts Author: Thompson, Josie E. In the past, sharks, skates and ray species have mainly occurred in incidental fisheries. Now they are increasingly being directly targeted due to the depleted status of traditionally targeted species. The life history characteristics of many elasmobranch species make them more sensitive to high rates of fishing mortality. The combination of these factors has resulted in the known local depletion of several elasmobranch species; including the barndoor skate, Raja laevis, of the Northwest Atlantic and the common skate, Raja batis, of Irish Sea. The longnose skate, Raja rhina, occurs commonly as incidental catch in trawl fisheries off the coast of California, Oregon and Washington. Commercial landings of skates, including R. rhina, have increased dramatically along the U.S. West coast. The objectives of this study have been to calculate accurate growth and maturity parameters for Raja rhina in order that the vulnerability of this species to fishing mortality can be assessed. The slow growth rates (k=0.04 to 0.06) and late ages-at-50% maturity (11 to 16 years with maximum ages between 15 and 22 years, depending on sex and region) which were calculated indicate that this species may be at great risk of depletion in the future. Survey biomass trends indicate that R. rhina populations have remained stable over the past twenty years. However, the possibility that biomass levels in the distant past were much higher than they are at present cannot be ruled out. It is recommended that the collection of fishery-dependent data for this species and other skate species begins immediately. This information, along with the results found in this are needed for a proper assessment for Raja rhina, so that the effects of current fishing pressures can be evaluated and regulated appropriately. Close

• 76. [Article] The morphology and taxonomic significance of the male genitalia of Coenonycha (Coleoptera, Scarabaeidae)

  The genus Coenonycha contains 30 described species of small to medium sized scarabs. They are found in the arid and semi-arid regions of western United States and northern Baja California. The adults feed ...

  Citation × Citation Citation Abstract Copy Title: The morphology and taxonomic significance of the male genitalia of Coenonycha (Coleoptera, Scarabaeidae) Author: Davidson, Jean Hoyt Puckle The genus Coenonycha contains 30 described species of small to medium sized scarabs. They are found in the arid and semi-arid regions of western United States and northern Baja California. The adults feed at night on several genera of xerophylous plants. An examination of the male genitalia of the 19 long-winged species indicates that the internal sac possesses characters which are stable within a species and are, therefore, taxonomically useful. These structures are a dorsal, toothed, knob-like sclerite and from one to four spinose fields on the enlarged portion of the sac. Variation in these structures within a species occurs in the number of teeth on the knob and spines in the fields. Sixteen new species of Coenonycha were discovered in the course of this study. They are indicated by letter in the text and phenetic tree and will be described elsewhere. The male genitalic structures of the 19 long-winged species are described in detail and illustrated. A key to these species, using primarily the basal knob and spinose fields is included. In addition, a key (modified from Cazier and Mc Clay, 1943) to all the described species of Coenonycha, using characters such as color, pilosity, clypeal reflection and pronatal punctation is provided. A key to the North American genera of Macrodacylini using the parameres, basal piece, basal apodeme, genital segment, and internal sac shows the diversity of genitalic structures in the tribe. Coenonycha, Dichelonyx, and Gymnopyge are presently placed with Macrodactylus and Isonychus in the Macrodactylini. Based on genitalic, larval, spiracular, and adult external morphological structures, Coenonycha, Dichelonyx, and Gymnopyge should be separated from the Macrodactylini and placed in the tribe Dichelonychini. Title: The morphology and taxonomic significance of the male genitalia of Coenonycha (Coleoptera, Scarabaeidae) Author: Davidson, Jean Hoyt Puckle The genus Coenonycha contains 30 described species of small to medium sized scarabs. They are found in the arid and semi-arid regions of western United States and northern Baja California. The adults feed at night on several genera of xerophylous plants. An examination of the male genitalia of the 19 long-winged species indicates that the internal sac possesses characters which are stable within a species and are, therefore, taxonomically useful. These structures are a dorsal, toothed, knob-like sclerite and from one to four spinose fields on the enlarged portion of the sac. Variation in these structures within a species occurs in the number of teeth on the knob and spines in the fields. Sixteen new species of Coenonycha were discovered in the course of this study. They are indicated by letter in the text and phenetic tree and will be described elsewhere. The male genitalic structures of the 19 long-winged species are described in detail and illustrated. A key to these species, using primarily the basal knob and spinose fields is included. In addition, a key (modified from Cazier and Mc Clay, 1943) to all the described species of Coenonycha, using characters such as color, pilosity, clypeal reflection and pronatal punctation is provided. A key to the North American genera of Macrodacylini using the parameres, basal piece, basal apodeme, genital segment, and internal sac shows the diversity of genitalic structures in the tribe. Coenonycha, Dichelonyx, and Gymnopyge are presently placed with Macrodactylus and Isonychus in the Macrodactylini. Based on genitalic, larval, spiracular, and adult external morphological structures, Coenonycha, Dichelonyx, and Gymnopyge should be separated from the Macrodactylini and placed in the tribe Dichelonychini. Close

• 77. [Article] Behavior of Nine Species of Pacific Rockfish after Hook-and-Line Capture, Recompression, and Release

  We evaluated the effect of barotrauma on the behavior of nine species of Pacific rockfish Sebastes spp. after hook-and-line capture and release using a video-equipped underwater release cage. Sampling ...

  Citation × Citation Citation Abstract Copy Title: Behavior of Nine Species of Pacific Rockfish after Hook-and-Line Capture, Recompression, and Release Author: Hannah, Robert W., Matteson, Keith M. We evaluated the effect of barotrauma on the behavior of nine species of Pacific rockfish Sebastes spp. after hook-and-line capture and release using a video-equipped underwater release cage. Sampling was conducted across a range of bottom depths (12-194 m), mostly where barotrauma resulting from an expanded swim bladder and gaseous release of dissolved blood gases would be expected. Behavioral impairment from barotrauma was depth related but highly species specific. Increased depth of capture was associated with lower behavioral scores for black rockfish S. melanops, blue rockfish S. mystinus, and yelloweye rockfish S. ruberrimus, but not for canary rockfish S. pinniger. Behaviorally impaired fish showed a decreased ability to maintain vertical orientation and were slower in exiting the release cage. Species differed in the degree of behavioral impairment resulting from barotrauma and in how rapidly behavioral impairment increased with depth of capture. When captured at depths between 40 and 99 m, blue rockfish showed the most serious behavioral impairment, 8 of 18 (44%) failing to swim away at the time of release and simply drifting off in a sideways or upside-down posture. In the same depth range all of the other species sampled showed only moderate behavioral impairment, which is indicative of some potential for survival after discard by the fishery. Surface observations of the external signs of barotrauma were variable among species and were poor indicators of which species would show behavioral impairment upon release at depth. Within individual species, however, the external signs of barotrauma were associated with an increased probability of behavioral impairment at time of release. Title: Behavior of Nine Species of Pacific Rockfish after Hook-and-Line Capture, Recompression, and Release Author: Hannah, Robert W., Matteson, Keith M. We evaluated the effect of barotrauma on the behavior of nine species of Pacific rockfish Sebastes spp. after hook-and-line capture and release using a video-equipped underwater release cage. Sampling was conducted across a range of bottom depths (12-194 m), mostly where barotrauma resulting from an expanded swim bladder and gaseous release of dissolved blood gases would be expected. Behavioral impairment from barotrauma was depth related but highly species specific. Increased depth of capture was associated with lower behavioral scores for black rockfish S. melanops, blue rockfish S. mystinus, and yelloweye rockfish S. ruberrimus, but not for canary rockfish S. pinniger. Behaviorally impaired fish showed a decreased ability to maintain vertical orientation and were slower in exiting the release cage. Species differed in the degree of behavioral impairment resulting from barotrauma and in how rapidly behavioral impairment increased with depth of capture. When captured at depths between 40 and 99 m, blue rockfish showed the most serious behavioral impairment, 8 of 18 (44%) failing to swim away at the time of release and simply drifting off in a sideways or upside-down posture. In the same depth range all of the other species sampled showed only moderate behavioral impairment, which is indicative of some potential for survival after discard by the fishery. Surface observations of the external signs of barotrauma were variable among species and were poor indicators of which species would show behavioral impairment upon release at depth. Within individual species, however, the external signs of barotrauma were associated with an increased probability of behavioral impairment at time of release. Close

• 78. [Article] Pathogenicity and Virulence of Pythium Species Obtained from Forest Nursery Soils on Douglas-Fir Seedlings

  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 [publisher] ...

  Citation × Citation Citation Abstract Copy Title: Pathogenicity and Virulence of Pythium Species Obtained from Forest Nursery Soils on Douglas-Fir Seedlings Author: Davis, Anne, Beck, Bryan R., Weiland, Jerry E. 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 [publisher] and can be found at: https://www.apsnet.org/publications/Pages/default.aspx. Title: Pathogenicity and Virulence of Pythium Species Obtained from Forest Nursery Soils on Douglas-Fir Seedlings Author: Davis, Anne, Beck, Bryan R., Weiland, Jerry E. 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 [publisher] and can be found at: https://www.apsnet.org/publications/Pages/default.aspx. Close

• 79. [Article] Resveratrol Influence on Lifespan among Caenorhabditis Elegans Genetic Variants & Implications for Personalized Medicine

  46 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, ...

  Citation × Citation Citation Abstract Copy Title: Resveratrol Influence on Lifespan among Caenorhabditis Elegans Genetic Variants & Implications for Personalized Medicine Author: Caul, Tela Amber Year: 2017 46 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2017 Title: Resveratrol Influence on Lifespan among Caenorhabditis Elegans Genetic Variants & Implications for Personalized Medicine Author: Caul, Tela Amber Year: 2017 46 pages. A thesis presented to the Department of Human Physiology and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Science, Spring 2017 Close

• 80. [Article] Plant community dynamics in remnant and restored Willamette Valley wetland prairies

  Invasion by exotic species can pose a major challenge for developing native plant communities in wetland restoration projects. Often native plant communities do not develop as anticipated in restored wetlands ...

  Citation × Citation Citation Abstract Copy Title: Plant community dynamics in remnant and restored Willamette Valley wetland prairies Author: Schwindt, Rachel A. Invasion by exotic species can pose a major challenge for developing native plant communities in wetland restoration projects. Often native plant communities do not develop as anticipated in restored wetlands due to colonization by exotic species that dominate the native plant community. Despite the time and expense to restore wetlands, there has been little long term research to compare plant communities in restored and natural wetland sites. Research into plant community diversity across several wetland sites over several years can provide a broader perspective into how these ecosystems recover from long-term disturbance. The objective of this study was to compare plant community change from 2000 to 2005 between restored and remnant wetland prairie sites in the southern Willamette Valley in Oregon to determine if exotic species abundance was consistent between these groups. Specific objectives included 1) comparing the diversity and abundance of all species in remnant and restored wetland prairie sites, 2) evaluate the trajectory of community change between remnant and restored wetland prairie sites to determine if there was rapid change in restored sites, and 3) describe the plot level heterogeneity of the plant community in all sites to determine how microsites influence diversity. In 2005, species abundance was re-measured in four remnant wetland prairies and four restored wetland prairies that had been selected for an unrelated vegetation survey in 2000. Species were characterized by life form, origin, and wetland indicator status. Species abundance between groups of remnant and restored sites were compared using a multi-response permutation procedure (MRPP). The plant community trajectory was evaluated with nonmetric multidimensional scaling (NMS) and tested for significance with multivariate analysis of variance (MANOVA). Species area curves were compared between sites and within remnant and restored groups of plots. Within-year and between-year significance tests indicated that remnant and restored sites were similar in exotic species abundance, graminoid abundance, and wetland species abundance with no significant difference between these remnant and restored wetland prairie sites. Individual sites in both groups experienced changes in exotic species abundance which confounded the statistical results. Species heterogeneity was no more spatially diverse across the remnant site plots than restored site plots. Species area curves did not show significant differences between remnant and restored plots but individual plots did show homogeneous community characteristics at smaller spatial scales. Restoration sites had developed high graminoid cover by the 2000 survey which was conducted two to three years after restoration was initiated. All sites were equally likely to contain exotic species. Exotic species common across all sites included Centaurium umbellatum, Holcus lanatus, and Hypericum perforatum. Native species common across sites included Deschampsia cespitosa, Danthonia californica and Juncus tenuis. These results suggested that differences between remnant and restored Willamette Valley wetland prairie sites were not generalizable at the landscape scale and were more dependent on site specific management activities and local barriers to colonization. Five years may not be enough time to see evidence that suggests if restored plant communities will develop spatial characteristics of the remnant sites. This research does suggest that multi-site comparisons help distinguish individual sites that are not developing characteristics of remnant wetland plant communities. Title: Plant community dynamics in remnant and restored Willamette Valley wetland prairies Author: Schwindt, Rachel A. Invasion by exotic species can pose a major challenge for developing native plant communities in wetland restoration projects. Often native plant communities do not develop as anticipated in restored wetlands due to colonization by exotic species that dominate the native plant community. Despite the time and expense to restore wetlands, there has been little long term research to compare plant communities in restored and natural wetland sites. Research into plant community diversity across several wetland sites over several years can provide a broader perspective into how these ecosystems recover from long-term disturbance. The objective of this study was to compare plant community change from 2000 to 2005 between restored and remnant wetland prairie sites in the southern Willamette Valley in Oregon to determine if exotic species abundance was consistent between these groups. Specific objectives included 1) comparing the diversity and abundance of all species in remnant and restored wetland prairie sites, 2) evaluate the trajectory of community change between remnant and restored wetland prairie sites to determine if there was rapid change in restored sites, and 3) describe the plot level heterogeneity of the plant community in all sites to determine how microsites influence diversity. In 2005, species abundance was re-measured in four remnant wetland prairies and four restored wetland prairies that had been selected for an unrelated vegetation survey in 2000. Species were characterized by life form, origin, and wetland indicator status. Species abundance between groups of remnant and restored sites were compared using a multi-response permutation procedure (MRPP). The plant community trajectory was evaluated with nonmetric multidimensional scaling (NMS) and tested for significance with multivariate analysis of variance (MANOVA). Species area curves were compared between sites and within remnant and restored groups of plots. Within-year and between-year significance tests indicated that remnant and restored sites were similar in exotic species abundance, graminoid abundance, and wetland species abundance with no significant difference between these remnant and restored wetland prairie sites. Individual sites in both groups experienced changes in exotic species abundance which confounded the statistical results. Species heterogeneity was no more spatially diverse across the remnant site plots than restored site plots. Species area curves did not show significant differences between remnant and restored plots but individual plots did show homogeneous community characteristics at smaller spatial scales. Restoration sites had developed high graminoid cover by the 2000 survey which was conducted two to three years after restoration was initiated. All sites were equally likely to contain exotic species. Exotic species common across all sites included Centaurium umbellatum, Holcus lanatus, and Hypericum perforatum. Native species common across sites included Deschampsia cespitosa, Danthonia californica and Juncus tenuis. These results suggested that differences between remnant and restored Willamette Valley wetland prairie sites were not generalizable at the landscape scale and were more dependent on site specific management activities and local barriers to colonization. Five years may not be enough time to see evidence that suggests if restored plant communities will develop spatial characteristics of the remnant sites. This research does suggest that multi-site comparisons help distinguish individual sites that are not developing characteristics of remnant wetland plant communities. Close