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• 201. [Image] The Third Klamath Basin Watershed Restoration and Research Conference

  	Cover title; "March 1999."
  	Citation × Citation Citation Abstract Copy Title: The Third Klamath Basin Watershed Restoration and Research Conference Year: 1999, 2004 Cover title; "March 1999." Title: The Third Klamath Basin Watershed Restoration and Research Conference Year: 1999, 2004 Cover title; "March 1999." Close

• 202. [Article] Distribution patterns of reptiles and amphibians in Puerto Rico

  This study examined the question of whether a big island can be divided into many smaller islands with the same pattern of area-species curve as that of the complete island. To address this question, this ...

  Citation × Citation Citation Abstract Copy Title: Distribution patterns of reptiles and amphibians in Puerto Rico Author: Le, Minh Duc, 1973- This study examined the question of whether a big island can be divided into many smaller islands with the same pattern of area-species curve as that of the complete island. To address this question, this study used data on the number and distribution of amphibians and reptiles on Puerto Rico and landbridge islands of the Puerto Rican Bank, which were fragmented from the big island about 10,000 years ago. In Puerto Rico, the data show correlations between the number of species and area available at different elevation levels and between species and area after removing effects of elevation. These patterns are different from the patterns of correlation between area and the number of reptiles and amphibians on 29 islands on the Puerto Rican Bank. The area-species curves of the elevationally and areally subdivided "islands" on Puerto Rico tend to have steeper slopes than the curves of the Puerto Rican Bank islands. Analyses of area and the number of those species on fragmented habitat islands at different elevations also indicated correlation between them. However, patterns of correlation seem not to be the same at each altitude. The slope of the area-species curve seems to decrease with increasing elevation levels. Other patterns of species distribution of Puerto Rico's herpetofauna are: there are linear relationships between the number of species and elevation, the number of species and distance from the coast, and the number of species and the species range areas. Multiple regression analyses of three variables: area, precipitation, and elevation, suggested that variation of species distribution in Puerto Rico is partly caused by interactions among these variables. Elevation plays an especially important role in explaining reptile and amphibian distribution. The rainfall variable had the least effect on determining herpetofauna diversity. The study results suggest that area-species correlation is a consequence of habitat heterogeneity on the island. Title: Distribution patterns of reptiles and amphibians in Puerto Rico Author: Le, Minh Duc, 1973- This study examined the question of whether a big island can be divided into many smaller islands with the same pattern of area-species curve as that of the complete island. To address this question, this study used data on the number and distribution of amphibians and reptiles on Puerto Rico and landbridge islands of the Puerto Rican Bank, which were fragmented from the big island about 10,000 years ago. In Puerto Rico, the data show correlations between the number of species and area available at different elevation levels and between species and area after removing effects of elevation. These patterns are different from the patterns of correlation between area and the number of reptiles and amphibians on 29 islands on the Puerto Rican Bank. The area-species curves of the elevationally and areally subdivided "islands" on Puerto Rico tend to have steeper slopes than the curves of the Puerto Rican Bank islands. Analyses of area and the number of those species on fragmented habitat islands at different elevations also indicated correlation between them. However, patterns of correlation seem not to be the same at each altitude. The slope of the area-species curve seems to decrease with increasing elevation levels. Other patterns of species distribution of Puerto Rico's herpetofauna are: there are linear relationships between the number of species and elevation, the number of species and distance from the coast, and the number of species and the species range areas. Multiple regression analyses of three variables: area, precipitation, and elevation, suggested that variation of species distribution in Puerto Rico is partly caused by interactions among these variables. Elevation plays an especially important role in explaining reptile and amphibian distribution. The rainfall variable had the least effect on determining herpetofauna diversity. The study results suggest that area-species correlation is a consequence of habitat heterogeneity on the island. Close

• 203. [Article] A Phylogenetic Perspective on the Individual Species- Area Relationship in Temperate and Tropical Tree Communities

  This is the publisher’s final pdf. The published article is copyrighted by Public Library of Science and can be found at: http://www.plos.org/.

  Citation × Citation Citation Abstract Copy Title: A Phylogenetic Perspective on the Individual Species- Area Relationship in Temperate and Tropical Tree Communities Author: Kenfack, David, Howe, Robert, Cao, Min, Ewango, Corneille E. N., Chuyong, George B., Swenson, Nathan G., Lin, Luxiang, Yang, Jie, Thomas, Duncan, Wolf, Amy This is the publisher’s final pdf. The published article is copyrighted by Public Library of Science and can be found at: http://www.plos.org/. Title: A Phylogenetic Perspective on the Individual Species- Area Relationship in Temperate and Tropical Tree Communities Author: Kenfack, David, Howe, Robert, Cao, Min, Ewango, Corneille E. N., Chuyong, George B., Swenson, Nathan G., Lin, Luxiang, Yang, Jie, Thomas, Duncan, Wolf, Amy This is the publisher’s final pdf. The published article is copyrighted by Public Library of Science and can be found at: http://www.plos.org/. Close

• 204. [Article] Wood density patterns of young Costa Rican trees in planted and natural forests

  In plantation forestry, rapid growth rate is favorable for wood production, but may decrease wood density, which is an important indicator of wood quality for both pulp and solid wood products. I looked ...

  Citation × Citation Citation Abstract Copy Title: Wood density patterns of young Costa Rican trees in planted and natural forests Author: Baker, David C. In plantation forestry, rapid growth rate is favorable for wood production, but may decrease wood density, which is an important indicator of wood quality for both pulp and solid wood products. I looked for (1) differences in radial patterns of wood density between planted and naturally grown Costa Rican tree species, and (2) between species characteristic of different successional stages. Trees were sampled from seven- and eleven-year-old research plantations and the nearby forests at La Selva Biological Station, Costa Rica and analyzed by x-ray densitometry at Oregon State University. Four of eight tree species had significantly higher wood densities for naturally grown trees than for the seven-year-old planted trees as shown by x-ray densitometry. Two species had significantly higher wood density for planted trees, and the two remaining species showed no significant differences between planted and naturally grown trees. Height-diameter ratios for eleven-year-old trees were higher for later successional species than for early successional species, and later successional species showed greater increases in wood density than early successional species. As expected, wood density was lowest in early successional species. The index S (ht/(dia*SG)) was expected to correlate with successional status. S provided an accurate prediction of relative successional order, with high values representing late successional species, due to the unexpected height-diameter ratio results. The results show that early-successional tree species do not necessarily have rapid height growth at the expense of diameter growth, nor a related radial increase in wood density. Different species had different patterns of wood density and/or height-to-diameter ratios that defied simple generalizations. More research is necessary to understand the underlying reasons for this the observed variation, rather than reject outright previously held generalities in the literature. Preferably, such studies will use older trees, larger sample sizes, and better-documented and more diverse growing conditions in plantations. Title: Wood density patterns of young Costa Rican trees in planted and natural forests Author: Baker, David C. In plantation forestry, rapid growth rate is favorable for wood production, but may decrease wood density, which is an important indicator of wood quality for both pulp and solid wood products. I looked for (1) differences in radial patterns of wood density between planted and naturally grown Costa Rican tree species, and (2) between species characteristic of different successional stages. Trees were sampled from seven- and eleven-year-old research plantations and the nearby forests at La Selva Biological Station, Costa Rica and analyzed by x-ray densitometry at Oregon State University. Four of eight tree species had significantly higher wood densities for naturally grown trees than for the seven-year-old planted trees as shown by x-ray densitometry. Two species had significantly higher wood density for planted trees, and the two remaining species showed no significant differences between planted and naturally grown trees. Height-diameter ratios for eleven-year-old trees were higher for later successional species than for early successional species, and later successional species showed greater increases in wood density than early successional species. As expected, wood density was lowest in early successional species. The index S (ht/(dia*SG)) was expected to correlate with successional status. S provided an accurate prediction of relative successional order, with high values representing late successional species, due to the unexpected height-diameter ratio results. The results show that early-successional tree species do not necessarily have rapid height growth at the expense of diameter growth, nor a related radial increase in wood density. Different species had different patterns of wood density and/or height-to-diameter ratios that defied simple generalizations. More research is necessary to understand the underlying reasons for this the observed variation, rather than reject outright previously held generalities in the literature. Preferably, such studies will use older trees, larger sample sizes, and better-documented and more diverse growing conditions in plantations. Close

• 205. [Image] An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 1]

  	Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 1. Gen. Tech. Rep. PNW-GTR-405. ...
  	Citation × Citation Citation Abstract Copy Title: An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 1] Author: Quigley, Thomas Milton; Arbelbide, S. J. (Sylvia J.) Year: 1997, 2008, 2005 Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 1. Gen. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 vol. (Quigley, Thomas M., tech. ed.; The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment). The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basin. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area covers about 8 percent of the U.S. land area, 24 percent of the Nation's National Forest System lands, 10 percent of the Nation's BLM-administered lands, and contains about 1.2 percent of the Nation's population. This results in a population density that is less than one-sixth of the U.S. average. The area has experienced recent, rapid population growth and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease than under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than others. Aquatic systems are now more fragmented and isolated than historically and the introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit. Keywords: Columbia basin, biophysical systems, social systems, ecosystem. Title: An assessment of ecosystem components in the interior Columbia Basin and portions of the Klamath and Great Basins [volume 1] Author: Quigley, Thomas Milton; Arbelbide, S. J. (Sylvia J.) Year: 1997, 2008, 2005 Quigley, Thomas M.; Arbelbide, Sylvia J., tech. eds. 1997. An assessment of ecosystem components in the interior Columbia basin and portions of the Klamath and Great Basins: volume 1. Gen. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 vol. (Quigley, Thomas M., tech. ed.; The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment). The Assessment of Ecosystem Components in the Interior Columbia Basin and Portions of the Klamath and Great Basins provides detailed information about current conditions and trends for the biophysical and social systems within the Basin. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to smaller geographic areas. The Assessment area covers about 8 percent of the U.S. land area, 24 percent of the Nation's National Forest System lands, 10 percent of the Nation's BLM-administered lands, and contains about 1.2 percent of the Nation's population. This results in a population density that is less than one-sixth of the U.S. average. The area has experienced recent, rapid population growth and generally has a robust, diverse economy. As compared to historic conditions, the terrestrial, aquatic, forest, and rangeland systems have undergone dramatic changes. Forested landscapes are more susceptible to fire, insect, and disease than under historic conditions. Rangelands are highly susceptible to noxious weed invasion. The disturbance regimes that operate on forest and rangeland have changed substantially, with lethal fires dominating many areas where non-lethal fires were the norm historically. Terrestrial habitats that have experienced the greatest decline include the native grassland, native shrubland, and old forest structures. There are areas within the Assessment area that have higher diversity than others. Aquatic systems are now more fragmented and isolated than historically and the introduction of non-native fish species has complicated current status of native fishes. Core habitat and population centers do remain as building blocks for restoration. Social and economic conditions within the Assessment area vary considerably, depending to a great extent on population, diversity of employment opportunities, and changing demographics. Those counties with the higher population densities and greater diversity of employment opportunities are generally more resilient to economic downturns. This Assessment provides a rich information base, including over 170 mapped themes with associated models and databases, from which future decisions can benefit. Keywords: Columbia basin, biophysical systems, social systems, ecosystem. Close

• 206. [Article] The effects of density and proportion on spring wheat and Lolium multiflorum Lam

  This thesis consists of four chapters. Literature is reviewed in Chapter 1. Chapter 2 describes an addition series experiment to determine the influence of species density and proportion on vegetative ...

  Citation × Citation Citation Abstract Copy Title: The effects of density and proportion on spring wheat and Lolium multiflorum Lam Author: Concannon, Julie Ann This thesis consists of four chapters. Literature is reviewed in Chapter 1. Chapter 2 describes an addition series experiment to determine the influence of species density and proportion on vegetative and reproductive yield of spring wheat and Lolium multiflorum. Chapter 3 consists of a growth analysis experiment to determine whether proximity factors and time and temperature (incorporated into growing degree day units) affect the growth rates of species height, leaf number, tiller number, and leaf area index. The final chapter contains conclusions drawn from both experiments. A review of competition literature indicates that yield-density relationships can be studied using additive studies, replacement series, and addition series experiments. Intra- and interspecific competitive responses may be quantified best with the latter two approaches. Additive studies confound variables of species density and adequately Spring multiflorum proportion and therefore, do not assess competitive responses of weed and crop. wheat (Triticum aestivum) (L.) and Lolium (Lam.) were grown together in an addition series to examine the influence of species density and proportion on vegetative and reproductive biomass. Wheat grain yields indicated that yield increased with wheat monoculture density. However, the increase in grain yield was not linear, indicating that constant final yield occurred at high wheat monoculture densities. Grain yield decreased with increasing ryegrass density. These observations suggest that both intra- and interspecific competition occurred during the study. Grain yield was highly correlated with total biomass. Therefore mean plant biomass was used as a competitive predictive regression models. Regression results indicate that wheat was a more effective competitor than ryegrass over all species relative and total densities. A model was developed by regressing mean reciprocal weight as a response to final densities of both species. Relative competitive abilities were calculated for each species. The relative competitive ability of wheat suggests that one wheat plant was as competitive as 6.7 ryegrass plants. However, wheat also was more competitive with itself than with ryegrass. Ryegrass relative competitive ability indicated that one ryegrass plant was as competitive as one wheat or ryegrass plant. Species density and proportion and time and temperature (incorporated in growing degree day units (GDD)) were included in the regression model as independent variables to describe relative rates of plant growth for both species. Growth parameters (seed size, height, leaf number, tiller number, and leaf area index (LAI)) were measured throughout the growing season. Analysis of variance and covariance on relative rates of growth and seasonal LAI indicated that proximity factors of species density and proportion influenced relative rates of growth and seasonal LAI of both species. GDD was usually a significant variable in the regression equations, suggesting that time and temperature also influenced rates of growth. The regression equations describing relative rates of growth indicate that wheat, by virtue of a large seed size and high early season LAI, captured a large share of resources by germinating fast and quickly overtopping ryegrass in the mixture. The trend continued throughout the season. However, suppressed ryegrass plants maintained a constant rate of growth. Ryegrass eventually grew as tall or taller than wheat plants and produced a higher LAI than wheat in mixtures. This may be a growth strategy which makes ryegrass a persistent weed in spring wheat cropping systems. Title: The effects of density and proportion on spring wheat and Lolium multiflorum Lam Author: Concannon, Julie Ann This thesis consists of four chapters. Literature is reviewed in Chapter 1. Chapter 2 describes an addition series experiment to determine the influence of species density and proportion on vegetative and reproductive yield of spring wheat and Lolium multiflorum. Chapter 3 consists of a growth analysis experiment to determine whether proximity factors and time and temperature (incorporated into growing degree day units) affect the growth rates of species height, leaf number, tiller number, and leaf area index. The final chapter contains conclusions drawn from both experiments. A review of competition literature indicates that yield-density relationships can be studied using additive studies, replacement series, and addition series experiments. Intra- and interspecific competitive responses may be quantified best with the latter two approaches. Additive studies confound variables of species density and adequately Spring multiflorum proportion and therefore, do not assess competitive responses of weed and crop. wheat (Triticum aestivum) (L.) and Lolium (Lam.) were grown together in an addition series to examine the influence of species density and proportion on vegetative and reproductive biomass. Wheat grain yields indicated that yield increased with wheat monoculture density. However, the increase in grain yield was not linear, indicating that constant final yield occurred at high wheat monoculture densities. Grain yield decreased with increasing ryegrass density. These observations suggest that both intra- and interspecific competition occurred during the study. Grain yield was highly correlated with total biomass. Therefore mean plant biomass was used as a competitive predictive regression models. Regression results indicate that wheat was a more effective competitor than ryegrass over all species relative and total densities. A model was developed by regressing mean reciprocal weight as a response to final densities of both species. Relative competitive abilities were calculated for each species. The relative competitive ability of wheat suggests that one wheat plant was as competitive as 6.7 ryegrass plants. However, wheat also was more competitive with itself than with ryegrass. Ryegrass relative competitive ability indicated that one ryegrass plant was as competitive as one wheat or ryegrass plant. Species density and proportion and time and temperature (incorporated in growing degree day units (GDD)) were included in the regression model as independent variables to describe relative rates of plant growth for both species. Growth parameters (seed size, height, leaf number, tiller number, and leaf area index (LAI)) were measured throughout the growing season. Analysis of variance and covariance on relative rates of growth and seasonal LAI indicated that proximity factors of species density and proportion influenced relative rates of growth and seasonal LAI of both species. GDD was usually a significant variable in the regression equations, suggesting that time and temperature also influenced rates of growth. The regression equations describing relative rates of growth indicate that wheat, by virtue of a large seed size and high early season LAI, captured a large share of resources by germinating fast and quickly overtopping ryegrass in the mixture. The trend continued throughout the season. However, suppressed ryegrass plants maintained a constant rate of growth. Ryegrass eventually grew as tall or taller than wheat plants and produced a higher LAI than wheat in mixtures. This may be a growth strategy which makes ryegrass a persistent weed in spring wheat cropping systems. Close

• 207. [Image] Williamson River delta restoration project : environmental assessment

  	"May 2000"; From cover: Prepared for U.S. Department of Agriculture/Natural Resources Conservation Service, 2316 South 6th Street, Suite C, Klamath Falls, Oregon 97601. In Partnership with The Nature Conservancy, ...
  	Citation × Citation Citation Abstract Copy Title: Williamson River delta restoration project : environmental assessment Year: 2000, 2005 "May 2000"; From cover: Prepared for U.S. Department of Agriculture/Natural Resources Conservation Service, 2316 South 6th Street, Suite C, Klamath Falls, Oregon 97601. In Partnership with The Nature Conservancy, 821 SE 14th Avenue, Portland, Oregon 97214 and US Fish and Wildlife Service, US Bureau of Reclamation, Klamath Tribes, PacifiCorp, Cell Tech International; Includes bibliographic references (p. 60-66) Title: Williamson River delta restoration project : environmental assessment Year: 2000, 2005 "May 2000"; From cover: Prepared for U.S. Department of Agriculture/Natural Resources Conservation Service, 2316 South 6th Street, Suite C, Klamath Falls, Oregon 97601. In Partnership with The Nature Conservancy, 821 SE 14th Avenue, Portland, Oregon 97214 and US Fish and Wildlife Service, US Bureau of Reclamation, Klamath Tribes, PacifiCorp, Cell Tech International; Includes bibliographic references (p. 60-66) Close

• 208. [Article] The influence of tree cover and shade pattern upon the distribution of understory plants in ponderosa pine stands of central Oregon

  Seven sites of uniform topography and soil were selected within a self perpetuating ponderosa pine forest found on the eastern flank of the central Oregon Cascades. These plots were located along a vegetational ...

  Citation × Citation Citation Abstract Copy Title: The influence of tree cover and shade pattern upon the distribution of understory plants in ponderosa pine stands of central Oregon Author: Robinson, Andrew Frederick, Jr. Seven sites of uniform topography and soil were selected within a self perpetuating ponderosa pine forest found on the eastern flank of the central Oregon Cascades. These plots were located along a vegetational gradient caused mainly by an orographic rain shadow. Data gathered included density, frequency, and cover for all understory species, amount of direct overhead tree cover, and amount of shade cast by the tree canopy. An attempt was made to relate the distributional pattern of understory species to influences caused by shade, overhead tree cover, and shrub cover within each pIot. The Dfd index and Cole's index were statistical methods used to correlate the herbaceous species pattern to overhead tree cover, shrub cover, and shade. Of the two, Cole's index appeared to be a more sensitive tool for this study. All the shrub species with the exception of Purshia tridentata showed a consistent distributional pattern to insolation. The position along the vegetational gradient appeared to be related with the shrub's affinity for an insolation class. Those shrubs restricted to the mesic end of the gradient showed an affinity for Iow insolation or deep shade. Conversely, those shrubs occurring on the xeric end showed an affinity for higher insolation. Those shrubs found in the center of the gradient showed an affinity for moderate insolation. Ten herbaceous species out of a total of 16 observed showed apparent affinities for a certain microhabitat within the stand. Plot location, shade, overhead vertical crown cover, and shrub cover influenced the distribution of herbaceous species within the plot. Species found within mesic plots showed a weak affinity for cover, but those on xeric plots showed a strong affinity for cover. A weak indication of the spatial ecological niche was gained for 15 herbaceous species, but a strong indication was observed for Trientalis latifolia. Similarly, some insight into the ecological performance of the species was gained in regard to insolation. Usually the plot location coincided with the species' affinity for an insolation class. If the species occurred mainly on the mesic end of the gradient, it showed an affinity, for deep shade (Lupinus caudatus, Fragaria virginiana, Trientalis latifolia, and Pteridium aquilinum). If the species occurred mainly on the xeric end of the gradient, it showed an affinity for high insolation (Viola purpurea, Carex inops, and Madia minirna). Five species showed some affinity for moderate insolation (Clarkia rhornboidea, Eriogonurn urnbellaturn, Kelloggia galioides , Mimulus nanus, and Stipa occidentalis), but the correlation with plot location was less clear. Four species (Festuca idahoensis, Sitanion hvstrix, Achillea rnillefoliurn, and Lathvrus lanswertii) were not restricted to any part of the gradient. These species showed preference to insolation with the plot, but this preference was not usually the same throughout the gradient. Indications of the limits of ecological potential were found for some of these species, in particular Achillea millefolium which did not occur on any plot where insolation was less than 10%. Title: The influence of tree cover and shade pattern upon the distribution of understory plants in ponderosa pine stands of central Oregon Author: Robinson, Andrew Frederick, Jr. Seven sites of uniform topography and soil were selected within a self perpetuating ponderosa pine forest found on the eastern flank of the central Oregon Cascades. These plots were located along a vegetational gradient caused mainly by an orographic rain shadow. Data gathered included density, frequency, and cover for all understory species, amount of direct overhead tree cover, and amount of shade cast by the tree canopy. An attempt was made to relate the distributional pattern of understory species to influences caused by shade, overhead tree cover, and shrub cover within each pIot. The Dfd index and Cole's index were statistical methods used to correlate the herbaceous species pattern to overhead tree cover, shrub cover, and shade. Of the two, Cole's index appeared to be a more sensitive tool for this study. All the shrub species with the exception of Purshia tridentata showed a consistent distributional pattern to insolation. The position along the vegetational gradient appeared to be related with the shrub's affinity for an insolation class. Those shrubs restricted to the mesic end of the gradient showed an affinity for Iow insolation or deep shade. Conversely, those shrubs occurring on the xeric end showed an affinity for higher insolation. Those shrubs found in the center of the gradient showed an affinity for moderate insolation. Ten herbaceous species out of a total of 16 observed showed apparent affinities for a certain microhabitat within the stand. Plot location, shade, overhead vertical crown cover, and shrub cover influenced the distribution of herbaceous species within the plot. Species found within mesic plots showed a weak affinity for cover, but those on xeric plots showed a strong affinity for cover. A weak indication of the spatial ecological niche was gained for 15 herbaceous species, but a strong indication was observed for Trientalis latifolia. Similarly, some insight into the ecological performance of the species was gained in regard to insolation. Usually the plot location coincided with the species' affinity for an insolation class. If the species occurred mainly on the mesic end of the gradient, it showed an affinity, for deep shade (Lupinus caudatus, Fragaria virginiana, Trientalis latifolia, and Pteridium aquilinum). If the species occurred mainly on the xeric end of the gradient, it showed an affinity for high insolation (Viola purpurea, Carex inops, and Madia minirna). Five species showed some affinity for moderate insolation (Clarkia rhornboidea, Eriogonurn urnbellaturn, Kelloggia galioides , Mimulus nanus, and Stipa occidentalis), but the correlation with plot location was less clear. Four species (Festuca idahoensis, Sitanion hvstrix, Achillea rnillefoliurn, and Lathvrus lanswertii) were not restricted to any part of the gradient. These species showed preference to insolation with the plot, but this preference was not usually the same throughout the gradient. Indications of the limits of ecological potential were found for some of these species, in particular Achillea millefolium which did not occur on any plot where insolation was less than 10%. Close

• 209. [Article] Rapid endangered species assessment : a novel approach to improve extinction risk assessments in poorly known species

  The number of endangered species is rapidly increasing while paucity of adequate information and resources delays establishment of conservation actions. The IUCN’s listing system is insufficient to determine ...

  Citation × Citation Citation Abstract Copy Title: Rapid endangered species assessment : a novel approach to improve extinction risk assessments in poorly known species Author: Bianchi, Carlos A. The number of endangered species is rapidly increasing while paucity of adequate information and resources delays establishment of conservation actions. The IUCN’s listing system is insufficient to determine conservation priorities and many species lack information even to be evaluated (i.e., “data deficient”). Here I proposed and tested the Rapid Endangered Species Assessment approach, combining methods including distribution modeling, landscape/habitat availability analysis and an evaluation of population spatial structure to improve information about species of concern and make future extinction risk assessments more attainable. I used the Pfrimer’s Parakeet (Pyrrhura pfrimeri) an endemic Brazilian species, as a case study. I modeled and validated the potential distribution of the species, known to occur in association with the tropical dry forests in central Brazil, using the Maxent method. The model predicted potential occurrence in three regions in central Brazil. Field surveys used to validate model found the species at 17 sites, all located in the dry forests of the Paranã River Basin. Modeling results set boundaries for the analysis of loss and fragmentation of the species’ habitat. Satellite imagery and remote sensing techniques were used to estimate deforestation trends over a large spatiotemporal scale (31 years). Results indicated a 66.3% decrease in forest extent, average annual deforestation rate of 2.1% and significant increase in fragmentation, suggesting that these forests may disappear in less than 20 years if current deforestation rates persist. The habitat availability analysis set boundaries for the investigation of spatial arrangement of local populations of Pfrimer’s Parakeets, which was carried out by collecting information on abundance, densities estimates, species home range, and habitat use. Twenty individuals were monitored with radio transmitters and home range estimates averaged between 195.7 ha (fixed kernel) and 261.8 ha (minimum convex polygons). Habitat use was estimated with behavioral observations of birds flying through a mosaic of forests and pastures. I found no evidence that the species used open areas farther than 300m from the forest edge. Systematic line transects and observations of parakeets per time effort produced estimates of population densities at 11.7 individuals/km2; indicating strong variation in abundance indices among areas, suggesting a population decline. The Rapid Endangered Species Assessment represents a broad and integrative approach carried out over a short term and was successfully used to produce relevant data about a poorly known species. Thus, I propose the use of this approach as a minimally ideal yet scientifically viable method to generate information for extinction risk assessment of species. Title: Rapid endangered species assessment : a novel approach to improve extinction risk assessments in poorly known species Author: Bianchi, Carlos A. The number of endangered species is rapidly increasing while paucity of adequate information and resources delays establishment of conservation actions. The IUCN’s listing system is insufficient to determine conservation priorities and many species lack information even to be evaluated (i.e., “data deficient”). Here I proposed and tested the Rapid Endangered Species Assessment approach, combining methods including distribution modeling, landscape/habitat availability analysis and an evaluation of population spatial structure to improve information about species of concern and make future extinction risk assessments more attainable. I used the Pfrimer’s Parakeet (Pyrrhura pfrimeri) an endemic Brazilian species, as a case study. I modeled and validated the potential distribution of the species, known to occur in association with the tropical dry forests in central Brazil, using the Maxent method. The model predicted potential occurrence in three regions in central Brazil. Field surveys used to validate model found the species at 17 sites, all located in the dry forests of the Paranã River Basin. Modeling results set boundaries for the analysis of loss and fragmentation of the species’ habitat. Satellite imagery and remote sensing techniques were used to estimate deforestation trends over a large spatiotemporal scale (31 years). Results indicated a 66.3% decrease in forest extent, average annual deforestation rate of 2.1% and significant increase in fragmentation, suggesting that these forests may disappear in less than 20 years if current deforestation rates persist. The habitat availability analysis set boundaries for the investigation of spatial arrangement of local populations of Pfrimer’s Parakeets, which was carried out by collecting information on abundance, densities estimates, species home range, and habitat use. Twenty individuals were monitored with radio transmitters and home range estimates averaged between 195.7 ha (fixed kernel) and 261.8 ha (minimum convex polygons). Habitat use was estimated with behavioral observations of birds flying through a mosaic of forests and pastures. I found no evidence that the species used open areas farther than 300m from the forest edge. Systematic line transects and observations of parakeets per time effort produced estimates of population densities at 11.7 individuals/km2; indicating strong variation in abundance indices among areas, suggesting a population decline. The Rapid Endangered Species Assessment represents a broad and integrative approach carried out over a short term and was successfully used to produce relevant data about a poorly known species. Thus, I propose the use of this approach as a minimally ideal yet scientifically viable method to generate information for extinction risk assessment of species. Close

• 210. [Article] Community organization and succession in rocky intertidal surfgrass beds

  Succession and organization of rocky intertidal zone surfgrass beds (Phyllospadix scouleri Hook) were examined experimentally at two sites on the Oregon coast. The interaction of three attributes of the ...

  Citation × Citation Citation Abstract Copy Title: Community organization and succession in rocky intertidal surfgrass beds Author: Turner, Teresa Succession and organization of rocky intertidal zone surfgrass beds (Phyllospadix scouleri Hook) were examined experimentally at two sites on the Oregon coast. The interaction of three attributes of the plant -- high persistence, high preemption, and slow recovery -- strongly influences the organization of surfgrass beds. Permanent plots indicate that surfgrass is persistent. Comparisons of experimental surfgrass removal and control plots demonstrate its preemptive ability, because removal plots are invaded by many algal species, but these algae are preempted from control plots. The slow growth of surfgrass rhizomes and the slower recruitment of surfgrass seeds indicate its recovery ability is low. The interaction of these phenomena produces a mosaic of surfgrass and algae in different successional stages. The successional sequence following a disturbance is more complex than predicted by any simple model because of temporal and spatial variation as well as differences in the species replacement mechanism. In some plots the early colonists, the perennial brown algal blade Phaeostrophion irregulare and the annual green algal blade Ulva sp., dominated for three years; in others they were replaced by a suite of middle successional species including the branched red algae Cryptosiphonia woodii. In other plots the slowest growing middle successional species, the branched red alga Rhodomela larix replaced other species. Part of this variability appears to be caused by large waves in the fall and winter, which remove large areas of algal cover, allowing dominant species to be replace by either earlier or later successional species. Part of the variability appears to be caused by local differences in the surfgrass understory before disturbance. Rhodomela larix is usually not completely removed by disturbance and regrows from its holdfast more readily than it recruits from spores. The mechanisms by which later species replace earlier ones differ depending on the successional stage. Established Phaeostrophion inhibits Ulva and filamentous diatoms. In contrast, certain middle successional species are necessary for seeds of the late successional surfgrass to recruit. The barbed seeds become attached to algal species with a central axis approximately 1 mm in diameter but not to algae with other forms. Title: Community organization and succession in rocky intertidal surfgrass beds Author: Turner, Teresa Succession and organization of rocky intertidal zone surfgrass beds (Phyllospadix scouleri Hook) were examined experimentally at two sites on the Oregon coast. The interaction of three attributes of the plant -- high persistence, high preemption, and slow recovery -- strongly influences the organization of surfgrass beds. Permanent plots indicate that surfgrass is persistent. Comparisons of experimental surfgrass removal and control plots demonstrate its preemptive ability, because removal plots are invaded by many algal species, but these algae are preempted from control plots. The slow growth of surfgrass rhizomes and the slower recruitment of surfgrass seeds indicate its recovery ability is low. The interaction of these phenomena produces a mosaic of surfgrass and algae in different successional stages. The successional sequence following a disturbance is more complex than predicted by any simple model because of temporal and spatial variation as well as differences in the species replacement mechanism. In some plots the early colonists, the perennial brown algal blade Phaeostrophion irregulare and the annual green algal blade Ulva sp., dominated for three years; in others they were replaced by a suite of middle successional species including the branched red algae Cryptosiphonia woodii. In other plots the slowest growing middle successional species, the branched red alga Rhodomela larix replaced other species. Part of this variability appears to be caused by large waves in the fall and winter, which remove large areas of algal cover, allowing dominant species to be replace by either earlier or later successional species. Part of the variability appears to be caused by local differences in the surfgrass understory before disturbance. Rhodomela larix is usually not completely removed by disturbance and regrows from its holdfast more readily than it recruits from spores. The mechanisms by which later species replace earlier ones differ depending on the successional stage. Established Phaeostrophion inhibits Ulva and filamentous diatoms. In contrast, certain middle successional species are necessary for seeds of the late successional surfgrass to recruit. The barbed seeds become attached to algal species with a central axis approximately 1 mm in diameter but not to algae with other forms. Close

• 211. [Article] Supplementary Data Terrestrial Mollusk Location and Species Count

  Supporting data in csv table format.

  Citation × Citation Citation Abstract Copy Title: Supplementary Data Terrestrial Mollusk Location and Species Count Author: Emery-Wetherell, Meaghan Marie, Mathew, Christine, Church, Cameron, Dellard, Ellie, Davis, Edward Byrd, Roering, Josh Year: 2017 Supporting data in csv table format. Title: Supplementary Data Terrestrial Mollusk Location and Species Count Author: Emery-Wetherell, Meaghan Marie, Mathew, Christine, Church, Cameron, Dellard, Ellie, Davis, Edward Byrd, Roering, Josh Year: 2017 Supporting data in csv table format. Close

• 212. [Article] Using a species-centered approach to examine patterns and drivers of avian species richness in the Rogue Basin, Oregon

  The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific ...

  Citation × Citation Citation Abstract Copy Title: Using a species-centered approach to examine patterns and drivers of avian species richness in the Rogue Basin, Oregon Author: Halstead, Katherine E. The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients for multiple species across broad spatial scales. Technologies such as fine-resolution remote sensing combined with enhanced species distribution modeling techniques hold promise for more accurate assessments of multi-species habitat distributions. In this research, I focused on forest bird species which utilize and/or are highly associated with threatened Oregon white oak and California black oak (Quercus garrayana and Q. kelloggii) vegetation types in the Rogue Basin of southwest Oregon. I created individual species distribution models (SDMs) for 48 bird species as a function of fine-resolution (30 x 30 m) remotely sensed land cover and other environmental variables using boosted regression tree (BRT) models. I then 'stacked' SDMs for spatially explicit regional estimates of multi-species avian richness. In my first chapter, I examined the potential for site-level species richness to be influenced by local vegetation and environmental conditions (e.g. the "local vegetation heterogeneity hypothesis") or by landscape-level dispersal potential (e.g. the "regional species pool hypothesis"). I summarized 'stacked' SDMs for indices of 1) habitat amount at a local scale relevant bird territory use and 2) habitat amount at a broad scale relevant to forest bird dispersal, and ask whether local- or landscape-scale habitat amount is relatively more important to site-level bird species richness. I hypothesized that greater importance of either habitat amount metric would indicate greater influence of local or landscape drivers to local richness. I found evidence that for a large pool of bird species with diverse habitat associations, landscape-scale habitat amount may be relatively more important to local (i.e., territory level) richness of forest birds than is local habitat amount. In contrast, for more specialized (i.e., oak-associated) guilds, local-scale habitat may be considerably more important than amount of habitat within the surrounding landscape. My results suggest the importance of local- and landscape-scale processes in structuring bird communities, supporting both 'local vegetation heterogeneity' and 'regional species pool' hypotheses. In my second chapter, I examined the relationships between landownership, oak vegetation distribution, and bird diversity, with the objective of determining which of five primary landownership types contribute most strongly to bird species habitat in the Rogue Basin. I asked whether individual bird species distributions and estimated richness are 'additive' or 'redundant' among land ownership types, hypothesizing that differences among owners will be apparent and related to the amount of oak-dominant vegetation held by each owner regionally. I found that estimated local mean species richness of oak-associated birds in private non-industrial (PNI) ownerships is approximately double that of other Rogue Basin public and private ownerships examined. This result may be driven by disproportionate PNI ownership of limited oak cover types, and/or by hypothesized variation in management goals and activities among owners which influence local vegetation structure. Relatively greater importance of territory-scale habitat to local oak-associated species richness suggests management for these species should maximize site-level habitat amount and quality. The importance of private non-industrial owners to oak-associated avian richness validates current focus on engaging private landowners in bird-focused oak conservation and restoration. Overall, my research links efforts to conserve avian habitat with efforts to understand multi-scale drivers of bird diversity, using a novel methodology that embraces the complexity of species' habitat gradients. Title: Using a species-centered approach to examine patterns and drivers of avian species richness in the Rogue Basin, Oregon Author: Halstead, Katherine E. The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients for multiple species across broad spatial scales. Technologies such as fine-resolution remote sensing combined with enhanced species distribution modeling techniques hold promise for more accurate assessments of multi-species habitat distributions. In this research, I focused on forest bird species which utilize and/or are highly associated with threatened Oregon white oak and California black oak (Quercus garrayana and Q. kelloggii) vegetation types in the Rogue Basin of southwest Oregon. I created individual species distribution models (SDMs) for 48 bird species as a function of fine-resolution (30 x 30 m) remotely sensed land cover and other environmental variables using boosted regression tree (BRT) models. I then 'stacked' SDMs for spatially explicit regional estimates of multi-species avian richness. In my first chapter, I examined the potential for site-level species richness to be influenced by local vegetation and environmental conditions (e.g. the "local vegetation heterogeneity hypothesis") or by landscape-level dispersal potential (e.g. the "regional species pool hypothesis"). I summarized 'stacked' SDMs for indices of 1) habitat amount at a local scale relevant bird territory use and 2) habitat amount at a broad scale relevant to forest bird dispersal, and ask whether local- or landscape-scale habitat amount is relatively more important to site-level bird species richness. I hypothesized that greater importance of either habitat amount metric would indicate greater influence of local or landscape drivers to local richness. I found evidence that for a large pool of bird species with diverse habitat associations, landscape-scale habitat amount may be relatively more important to local (i.e., territory level) richness of forest birds than is local habitat amount. In contrast, for more specialized (i.e., oak-associated) guilds, local-scale habitat may be considerably more important than amount of habitat within the surrounding landscape. My results suggest the importance of local- and landscape-scale processes in structuring bird communities, supporting both 'local vegetation heterogeneity' and 'regional species pool' hypotheses. In my second chapter, I examined the relationships between landownership, oak vegetation distribution, and bird diversity, with the objective of determining which of five primary landownership types contribute most strongly to bird species habitat in the Rogue Basin. I asked whether individual bird species distributions and estimated richness are 'additive' or 'redundant' among land ownership types, hypothesizing that differences among owners will be apparent and related to the amount of oak-dominant vegetation held by each owner regionally. I found that estimated local mean species richness of oak-associated birds in private non-industrial (PNI) ownerships is approximately double that of other Rogue Basin public and private ownerships examined. This result may be driven by disproportionate PNI ownership of limited oak cover types, and/or by hypothesized variation in management goals and activities among owners which influence local vegetation structure. Relatively greater importance of territory-scale habitat to local oak-associated species richness suggests management for these species should maximize site-level habitat amount and quality. The importance of private non-industrial owners to oak-associated avian richness validates current focus on engaging private landowners in bird-focused oak conservation and restoration. Overall, my research links efforts to conserve avian habitat with efforts to understand multi-scale drivers of bird diversity, using a novel methodology that embraces the complexity of species' habitat gradients. Close

• 213. [Article] Distribution of Euphausiacea and Copepoda off Oregon in relation to oceanographic conditions

  Fifty-two one-meter plankton net samples from four stations off Newport, Oregon, were examined for composition and abundance of euphausiids and copepods. They provided data on dominance, species associations ...

  Citation × Citation Citation Abstract Copy Title: Distribution of Euphausiacea and Copepoda off Oregon in relation to oceanographic conditions Author: Hebard, James Frank Fifty-two one-meter plankton net samples from four stations off Newport, Oregon, were examined for composition and abundance of euphausiids and copepods. They provided data on dominance, species associations and environmental relationships. The euphausiid-copepod population off Oregon is composed of 12 numerically dominant species. These species occurred in most of the samples regardless of season or location. In order of their percentage contribution these species were Euphausia pacifica, Metridia pacifica, Calanus finmarchicus, Calanus pacificus, Eucalanus bungii, Calanus plumchrus, Calanus A., Metridia lucens, Thysanoessa spinifera, Acartia longiremis, Aetideus armatus and Calanus tenuico rnis. Sixty-seven other species were collected, several undergoing distributional changes in response to changing oceanographic conditions. Three species, Nematoscelis difficilis (d), Rhincalanus nasutus and Acartia danae are associated with the fall influx of water from the south . Tessarabrachion oculatus, Eucalanus elongatus hyalinus, Pseudocalanus minutus and Oithona spinirostris were primarily summer species. Eighteen other species occurred consistently at NH-45 and beyond throughout the year with an occasional shoreward extension in distribution during the winter. Two methods of association analysis were used. The Fager- McConnaughey method, which utilizes only presence or absence, produced 47 separate associations. Most of these were determined by a few infrequent or rare species. The Sanders method, which utilizes relative abundance, produced six basic associations which differed mainly in the proportions of the dominant species rather than major changes in species composition. Neither method revealed well defined communities off Oregon, probably because of the absence of rapid or extreme fluctuations in the environment or because of the small geographical area sampled. The similarity between species associations were compared with the temperature and salinity relationships indicative of changes in the physical environment. Higher affinities occurred between samples taken under similar temperature and salinity conditions than occurred between samples from different conditions. Title: Distribution of Euphausiacea and Copepoda off Oregon in relation to oceanographic conditions Author: Hebard, James Frank Fifty-two one-meter plankton net samples from four stations off Newport, Oregon, were examined for composition and abundance of euphausiids and copepods. They provided data on dominance, species associations and environmental relationships. The euphausiid-copepod population off Oregon is composed of 12 numerically dominant species. These species occurred in most of the samples regardless of season or location. In order of their percentage contribution these species were Euphausia pacifica, Metridia pacifica, Calanus finmarchicus, Calanus pacificus, Eucalanus bungii, Calanus plumchrus, Calanus A., Metridia lucens, Thysanoessa spinifera, Acartia longiremis, Aetideus armatus and Calanus tenuico rnis. Sixty-seven other species were collected, several undergoing distributional changes in response to changing oceanographic conditions. Three species, Nematoscelis difficilis (d), Rhincalanus nasutus and Acartia danae are associated with the fall influx of water from the south . Tessarabrachion oculatus, Eucalanus elongatus hyalinus, Pseudocalanus minutus and Oithona spinirostris were primarily summer species. Eighteen other species occurred consistently at NH-45 and beyond throughout the year with an occasional shoreward extension in distribution during the winter. Two methods of association analysis were used. The Fager- McConnaughey method, which utilizes only presence or absence, produced 47 separate associations. Most of these were determined by a few infrequent or rare species. The Sanders method, which utilizes relative abundance, produced six basic associations which differed mainly in the proportions of the dominant species rather than major changes in species composition. Neither method revealed well defined communities off Oregon, probably because of the absence of rapid or extreme fluctuations in the environment or because of the small geographical area sampled. The similarity between species associations were compared with the temperature and salinity relationships indicative of changes in the physical environment. Higher affinities occurred between samples taken under similar temperature and salinity conditions than occurred between samples from different conditions. Close

• 214. [Article] Exploring stakeholders' attitudes and beliefs regarding behaviors that prevent the spread of invasive species : a focus group study

  This research explores the barriers that prevent stakeholders from changing their hobby behaviors to help prevent the spread of invasive species in Oregon. Invasive species are increasingly causing economic ...

  Citation × Citation Citation Abstract Copy Title: Exploring stakeholders' attitudes and beliefs regarding behaviors that prevent the spread of invasive species : a focus group study Author: Kubeck, Gwenn This research explores the barriers that prevent stakeholders from changing their hobby behaviors to help prevent the spread of invasive species in Oregon. Invasive species are increasingly causing economic and ecosystem harm in Oregon. This is among the first studies done on the human dimensions of invasive species. Using the Theory of Planned Behavior as a framework, the attitudes, norms and perceived behavioral controls regarding preventative behaviors were elucidated during four focus groups (29 individuals) with individual groupings of gardeners, anglers, hunters and boaters. Findings indicate six belief barriers to changing hobby behaviors. These include 1) the attitude that preventative behaviors, such as using pesticides, may be worse for the environment than invasive species, 2)the attitude that the fight against invasive species is a losing battle, 3)the norm belief that institutions don’t care enough to prioritize action on the issue of invasive species, 4) the norm belief that the general public both doesn’t know and doesn't care about invasive species, 5) the behavioral control belief that one doesn't know enough about the preventative behaviors to be effective, and 6) the behavioral control belief that preventative behaviors are too difficult to perform. Understanding the beliefs that prevent changes in behavior will help inform the creation of effective statewide invasive species awareness and actions campaigns, such as that being led by the Oregon Invasive Species Council, as well as provide a foundation of research on which to build additional research. Findings suggest that an effective way to engage stakeholders in being part of the solution to invasive species may include addressing social norms by targeting awareness messaging and engagement activities to hobby groups. Title: Exploring stakeholders' attitudes and beliefs regarding behaviors that prevent the spread of invasive species : a focus group study Author: Kubeck, Gwenn This research explores the barriers that prevent stakeholders from changing their hobby behaviors to help prevent the spread of invasive species in Oregon. Invasive species are increasingly causing economic and ecosystem harm in Oregon. This is among the first studies done on the human dimensions of invasive species. Using the Theory of Planned Behavior as a framework, the attitudes, norms and perceived behavioral controls regarding preventative behaviors were elucidated during four focus groups (29 individuals) with individual groupings of gardeners, anglers, hunters and boaters. Findings indicate six belief barriers to changing hobby behaviors. These include 1) the attitude that preventative behaviors, such as using pesticides, may be worse for the environment than invasive species, 2)the attitude that the fight against invasive species is a losing battle, 3)the norm belief that institutions don’t care enough to prioritize action on the issue of invasive species, 4) the norm belief that the general public both doesn’t know and doesn't care about invasive species, 5) the behavioral control belief that one doesn't know enough about the preventative behaviors to be effective, and 6) the behavioral control belief that preventative behaviors are too difficult to perform. Understanding the beliefs that prevent changes in behavior will help inform the creation of effective statewide invasive species awareness and actions campaigns, such as that being led by the Oregon Invasive Species Council, as well as provide a foundation of research on which to build additional research. Findings suggest that an effective way to engage stakeholders in being part of the solution to invasive species may include addressing social norms by targeting awareness messaging and engagement activities to hobby groups. Close

• 215. [Article] Effects of scale properties on biodiversity mapping in Oregon

  The effect of scale is an important concern in mapping of biodiversity. Scale issues include the grid cell size used for analysis and the effect of the extent and internal boundaries. Because biodiversity ...

  Citation × Citation Citation Abstract Copy Title: Effects of scale properties on biodiversity mapping in Oregon Author: Kennelly, Patrick J., (Patrick Joseph) The effect of scale is an important concern in mapping of biodiversity. Scale issues include the grid cell size used for analysis and the effect of the extent and internal boundaries. Because biodiversity analysis involves combinatorial processes, determining the proper scale is data dependent and cannot be predicted from the initial data values and their distribution. Biodiversity analysis often samples combinations of species within geopolitical boundaries. The effects of ecoregion boundaries on prioritization analysis was analyzed in two ways. This study determined that prioritization hexagons for Oregon do not fall preferentially on ecoregion boundaries. This research also concluded that results of prioritization analysis are geographically stable with the elimination of hexagons on ecoregion boundaries from analysis. Species maps based on the Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) grid were analyzed. Grid cells 7 times as large result in species richness maps statistically similar to maps made with the EMAP grid. Patterns of localized variation between grid cells indicate no one area is contributing to the overall variation. Prioritization maps, however, show different patterns of selected hexagons. Grid cells 49 times as large show a loss of species richness variation and a different pattern of prioritization hexagons. Richness maps based on wildlife habitat relations were used to map species richness at seven different three-fold compositions and decompositions of the EMAP grid. Analysis of statistics indicates that no scale shows a small relative decrease in coefficient of variation(CV), indicating no scale is relatively superior for richness mapping. Prioritization analysis was performed on the new combinations of species lists for five grid cell sizes ranging from 1/9 to 9X's the size of the EMAP grid. Efficiency of prioritization and map patterns of prioritization areas indicate that grid cells 1/3 the size of the EMAP hexagons are optimal. Comparisons can be made between the two biodiversity analyses at the EMAP scale for wildlife habitat vs. EMAP grid based species range maps. CV values have increased and the efficiency of prioritization is enhanced. This can be attributed to finer resolution sampling capturing additional information. Title: Effects of scale properties on biodiversity mapping in Oregon Author: Kennelly, Patrick J., (Patrick Joseph) The effect of scale is an important concern in mapping of biodiversity. Scale issues include the grid cell size used for analysis and the effect of the extent and internal boundaries. Because biodiversity analysis involves combinatorial processes, determining the proper scale is data dependent and cannot be predicted from the initial data values and their distribution. Biodiversity analysis often samples combinations of species within geopolitical boundaries. The effects of ecoregion boundaries on prioritization analysis was analyzed in two ways. This study determined that prioritization hexagons for Oregon do not fall preferentially on ecoregion boundaries. This research also concluded that results of prioritization analysis are geographically stable with the elimination of hexagons on ecoregion boundaries from analysis. Species maps based on the Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) grid were analyzed. Grid cells 7 times as large result in species richness maps statistically similar to maps made with the EMAP grid. Patterns of localized variation between grid cells indicate no one area is contributing to the overall variation. Prioritization maps, however, show different patterns of selected hexagons. Grid cells 49 times as large show a loss of species richness variation and a different pattern of prioritization hexagons. Richness maps based on wildlife habitat relations were used to map species richness at seven different three-fold compositions and decompositions of the EMAP grid. Analysis of statistics indicates that no scale shows a small relative decrease in coefficient of variation(CV), indicating no scale is relatively superior for richness mapping. Prioritization analysis was performed on the new combinations of species lists for five grid cell sizes ranging from 1/9 to 9X's the size of the EMAP grid. Efficiency of prioritization and map patterns of prioritization areas indicate that grid cells 1/3 the size of the EMAP hexagons are optimal. Comparisons can be made between the two biodiversity analyses at the EMAP scale for wildlife habitat vs. EMAP grid based species range maps. CV values have increased and the efficiency of prioritization is enhanced. This can be attributed to finer resolution sampling capturing additional information. Close

• 216. [Article] Range Contractions of North American Carnivores and Ungulates

  We compared the historic and current geographical ranges of 43 North American carnivores and ungulates to identify large-scale patterns in range contractions and expansions. Seventeen of the species had ...

  Citation × Citation Citation Abstract Copy Title: Range Contractions of North American Carnivores and Ungulates Author: Laliberte, Andrea S., Ripple, William J. We compared the historic and current geographical ranges of 43 North American carnivores and ungulates to identify large-scale patterns in range contractions and expansions. Seventeen of the species had experienced range contractions over more than 20% of their historic range. In areas of higher human influence, species were more likely to contract and less likely to persist. Species richness had also declined considerably since historic times. The temperate grasslands and temperate broadleaf–mixed forest biomes lost the highest average number of species, while the boreal forest and tundra showed fewer numbers of species lost. Species contractions were a result of Euro-American settlement and postsettlement development in North America. These effects have been widespread and indicate a rapid collapse of species distributions over the course of only 1 to 2 centuries. The results of this study can be used to improve scientists’ knowledge of historical reference conditions and to provide input for wildlife reintroductions and for the creation of wildlife reserves. Title: Range Contractions of North American Carnivores and Ungulates Author: Laliberte, Andrea S., Ripple, William J. We compared the historic and current geographical ranges of 43 North American carnivores and ungulates to identify large-scale patterns in range contractions and expansions. Seventeen of the species had experienced range contractions over more than 20% of their historic range. In areas of higher human influence, species were more likely to contract and less likely to persist. Species richness had also declined considerably since historic times. The temperate grasslands and temperate broadleaf–mixed forest biomes lost the highest average number of species, while the boreal forest and tundra showed fewer numbers of species lost. Species contractions were a result of Euro-American settlement and postsettlement development in North America. These effects have been widespread and indicate a rapid collapse of species distributions over the course of only 1 to 2 centuries. The results of this study can be used to improve scientists’ knowledge of historical reference conditions and to provide input for wildlife reintroductions and for the creation of wildlife reserves. Close

• 217. [Article] Fire effects on wetland prairie species: final report

  Project No. 14-48-0001-96749

  Citation × Citation Citation Abstract Copy Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Close

• 218. [Article] Exploring the Perspectives and Behaviors of Teachers on Invasive Species

  This study explores the role of classroom use of live organisms as a pathway for the spread of invasive species. The overall guiding research question is “Are behavioral changes necessary to reduce the ...

  Citation × Citation Citation Abstract Copy Title: Exploring the Perspectives and Behaviors of Teachers on Invasive Species Author: Root, Skye This study explores the role of classroom use of live organisms as a pathway for the spread of invasive species. The overall guiding research question is “Are behavioral changes necessary to reduce the spread from the classroom pathway?” Using focus groups comprised of key educators, this study seeks to identify attitudes, norms, and barriers to inform the development of solutions to mitigate the spread of aquatic invasive species from the classroom. A modified version of the Theory of Planned Behavior is used to tabulate values, knowledge, concerns, and solutions that could lead to behavioral change. A total of 65 educators participated in six different focus groups, with nearly half of the participants elementary teachers. Findings indicate strong educational, use-related, and ethical values deeply rooted in having, and continuing to have, live organisms in the classroom. Information about invasive species, however, is not perceived as readily available, and credible sources are often difficult to discern by participants who are mainly searching online for needed information. Logistical concerns, euthanization practices, ecological damages, and children’s outdoor experiences are described as potential barriers to behavior change, and educational liaisons, outreach activities, and policy changes are suggested solutions intended to change behavior. Using the Theory of Planned Behavior as a foundational theory and Multiple Streams framework as a policy guide, this study recommends five specific actions be taken by policy entrepreneurs: (1) Fund, develop, and maintain an invasive species informational website where educators can go for up-to-date references on sourcing, care and handling, disposal, and species identification. (2) Create example fact sheets for organism suppliers and encourage their adoption by the suppliers. (3) Add invasive species educational standards on a national scale through the NSTA and NISC, and provide teachers with curriculum suggestions involving the integration of invasive species education into core subject matter. (4) Develop and test an invasive species professional development training seminar for K-12 educators to be applied to large scale science association meetings or local in-service days. (5) Seek funding for the development of invasive species education curriculum that could be implemented through credentialing programs. Title: Exploring the Perspectives and Behaviors of Teachers on Invasive Species Author: Root, Skye This study explores the role of classroom use of live organisms as a pathway for the spread of invasive species. The overall guiding research question is “Are behavioral changes necessary to reduce the spread from the classroom pathway?” Using focus groups comprised of key educators, this study seeks to identify attitudes, norms, and barriers to inform the development of solutions to mitigate the spread of aquatic invasive species from the classroom. A modified version of the Theory of Planned Behavior is used to tabulate values, knowledge, concerns, and solutions that could lead to behavioral change. A total of 65 educators participated in six different focus groups, with nearly half of the participants elementary teachers. Findings indicate strong educational, use-related, and ethical values deeply rooted in having, and continuing to have, live organisms in the classroom. Information about invasive species, however, is not perceived as readily available, and credible sources are often difficult to discern by participants who are mainly searching online for needed information. Logistical concerns, euthanization practices, ecological damages, and children’s outdoor experiences are described as potential barriers to behavior change, and educational liaisons, outreach activities, and policy changes are suggested solutions intended to change behavior. Using the Theory of Planned Behavior as a foundational theory and Multiple Streams framework as a policy guide, this study recommends five specific actions be taken by policy entrepreneurs: (1) Fund, develop, and maintain an invasive species informational website where educators can go for up-to-date references on sourcing, care and handling, disposal, and species identification. (2) Create example fact sheets for organism suppliers and encourage their adoption by the suppliers. (3) Add invasive species educational standards on a national scale through the NSTA and NISC, and provide teachers with curriculum suggestions involving the integration of invasive species education into core subject matter. (4) Develop and test an invasive species professional development training seminar for K-12 educators to be applied to large scale science association meetings or local in-service days. (5) Seek funding for the development of invasive species education curriculum that could be implemented through credentialing programs. Close

• 219. [Article] Birds of the Coast Range of Lincoln County, Oregon : v.1. Birds of Thornton Creek

  Incidental to his outdoor activities such as farming, fern-picking, and horse logging, Darrel Faxon made 17.4 years of detailed observations at Thornton Creek during 1973-1990. He determined bird presence, ...

  Citation × Citation Citation Abstract Copy Title: Birds of the Coast Range of Lincoln County, Oregon : v.1. Birds of Thornton Creek Author: Bayer, Range D., 1947-, Faxon, Darrel Incidental to his outdoor activities such as farming, fern-picking, and horse logging, Darrel Faxon made 17.4 years of detailed observations at Thornton Creek during 1973-1990. He determined bird presence, not bird abundance, and made about 99,800 records, where a record is one bird species found during one day. Depending upon the calendar month, Faxon averaged 19-24 observation days/month, 13-34 bird species/day, and 34-66 species/month. He noted an average of 101 species each year. Faxon found 12 species only during casual observations prior to 1973 and 179 species in 1973-1990. He detected 47 waterbird species, so most birds he noted were terrestrial. 30% of waterbird species and 20% of terrestrial species were recorded in only one year, and just 16% of the waterbird species were seen in 16-18 years. However, Faxon noted the majority (50.4%) of terrestrial species in 16 or more years. For each species, daily relative frequencies of occurrence for each month and average monthly relative frequencies of occurrence for the 1973-1981 and 1982-1990 periods are given. Further, arrival and departure dates are listed for each species for each year, if appropriate. Faxon's records indicate that many migratory terrestrial species are often not present in the 10 days following their arrival or prior to their departure. Thus, determining arrival or departure dates may be very dependent upon daily observation effort. For example, if there are inadequate daily observations, then the actual arrival date may be missed, and it may be several days or a week before the species may re-appear. This inconsistency of presence after their "arrival" results in many species not being found on their "average" arrival date. Although Faxon did not record a spring migration wave, he usually noted a major movement of passerines during August-September. In fall, his records also indicate that some raptors appeared to be migrating through. In addition to his bird observations, Faxon recorded daily precipitation from 1975-1990, and monthly totals are given. Title: Birds of the Coast Range of Lincoln County, Oregon : v.1. Birds of Thornton Creek Author: Bayer, Range D., 1947-, Faxon, Darrel Incidental to his outdoor activities such as farming, fern-picking, and horse logging, Darrel Faxon made 17.4 years of detailed observations at Thornton Creek during 1973-1990. He determined bird presence, not bird abundance, and made about 99,800 records, where a record is one bird species found during one day. Depending upon the calendar month, Faxon averaged 19-24 observation days/month, 13-34 bird species/day, and 34-66 species/month. He noted an average of 101 species each year. Faxon found 12 species only during casual observations prior to 1973 and 179 species in 1973-1990. He detected 47 waterbird species, so most birds he noted were terrestrial. 30% of waterbird species and 20% of terrestrial species were recorded in only one year, and just 16% of the waterbird species were seen in 16-18 years. However, Faxon noted the majority (50.4%) of terrestrial species in 16 or more years. For each species, daily relative frequencies of occurrence for each month and average monthly relative frequencies of occurrence for the 1973-1981 and 1982-1990 periods are given. Further, arrival and departure dates are listed for each species for each year, if appropriate. Faxon's records indicate that many migratory terrestrial species are often not present in the 10 days following their arrival or prior to their departure. Thus, determining arrival or departure dates may be very dependent upon daily observation effort. For example, if there are inadequate daily observations, then the actual arrival date may be missed, and it may be several days or a week before the species may re-appear. This inconsistency of presence after their "arrival" results in many species not being found on their "average" arrival date. Although Faxon did not record a spring migration wave, he usually noted a major movement of passerines during August-September. In fall, his records also indicate that some raptors appeared to be migrating through. In addition to his bird observations, Faxon recorded daily precipitation from 1975-1990, and monthly totals are given. Close

• 220. [Article] Controlling woody vegetation in wetland prairies, 1994-1999

  Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining ...

  Citation × Citation Citation Abstract Copy Title: Controlling woody vegetation in wetland prairies, 1994-1999 Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After three treatments periods (1994, 1996, and 1998) the following patterns emerged: • Woody species Burning and hand-removal consistently caused the greatest reduction in cover of woody species. Mowing with removal of cut material did not reduce the abundance of woody species compared to the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species All management treatments consistently failed to significantly increase the cover of Deschampsia cespitosa, while burning decreased the number of inflorescences. As a group, native graminoid flowering consistently showed no significant responses to the management treatments. Although burning and hand-removal significantly increased the cover of native forbs as group after the second treatment period in 1997, native forbs showed no significant responses to treatments in 1999. • Non-native herbaceous species Response of non-native forb cover to management treatments has been inconsistent during the five year study period with no significant differences in 1995, significant reductions by burning and hand-removal in 1997, and increases with mowing in 1997. Mowing consistently increased flowering of nonnative graminoids as a group. Overall no treatment was clearly superior in fulfilling restoration objectives. Burning was effective in reducing woody cover and did not promote non-native herbaceous, but it reduced the flowering the dominant native grass, Deschampsia cespitosa. Hand-removal woody species was also effective at reducing woody cover and sometimes promoted the abundance of some native species at different times, but it also at times promoted non-native herbaceous species. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment is not a recommended management strategy. Title: Controlling woody vegetation in wetland prairies, 1994-1999 Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After three treatments periods (1994, 1996, and 1998) the following patterns emerged: • Woody species Burning and hand-removal consistently caused the greatest reduction in cover of woody species. Mowing with removal of cut material did not reduce the abundance of woody species compared to the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species All management treatments consistently failed to significantly increase the cover of Deschampsia cespitosa, while burning decreased the number of inflorescences. As a group, native graminoid flowering consistently showed no significant responses to the management treatments. Although burning and hand-removal significantly increased the cover of native forbs as group after the second treatment period in 1997, native forbs showed no significant responses to treatments in 1999. • Non-native herbaceous species Response of non-native forb cover to management treatments has been inconsistent during the five year study period with no significant differences in 1995, significant reductions by burning and hand-removal in 1997, and increases with mowing in 1997. Mowing consistently increased flowering of nonnative graminoids as a group. Overall no treatment was clearly superior in fulfilling restoration objectives. Burning was effective in reducing woody cover and did not promote non-native herbaceous, but it reduced the flowering the dominant native grass, Deschampsia cespitosa. Hand-removal woody species was also effective at reducing woody cover and sometimes promoted the abundance of some native species at different times, but it also at times promoted non-native herbaceous species. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment is not a recommended management strategy. Close

• 221. [Article] A biosystematic study in the genus Aster, section Aster, in western North America

  A biosystematic investigation was undertaken in 15 species and three subspecies of the genus Aster, in western North America. Previous studies had been based entirely on external morphological features, ...

  Citation × Citation Citation Abstract Copy Title: A biosystematic study in the genus Aster, section Aster, in western North America Author: Dean, Milton Lee A biosystematic investigation was undertaken in 15 species and three subspecies of the genus Aster, in western North America. Previous studies had been based entirely on external morphological features, and it was believed that much could be learned about the natural affinities of the taxa by exploring their cytological and genetical characteristics. More than 160 accessions were made during the course of the study. In the majority of cases, living rhizomes were transplanted in the greenhouse to provide material for making chromosome counts and hybridization experiments. Whenever possible, chromosomes were observed during meiotic divisions in microsporogenesis. One or more chromosome counts were made in 17 of the 18 taxa studied, 12 of which had not previously been examined cytologically. Ten taxa were found to include plants at two or more chromosome levels. The entire assemblage of species contains chromosome numbers on the basis of X = 8, with counts ranging from n = 8 to n = 48. Examples of aneuploidy, B-chromosomes, and meiotic irregularities were also discovered. A total of 383 artificial hybridizations was made among the species studied, resulting in the production of at least one fruit from 198 crosses. Most of the attempted crosses were interspecific, with the results indicating a striking lack of genetic incompatibility between the species at all polyploid levels. However, nearly all crosses involving diploid plants produced no fruits. First-generation hybrids of most species combinations were grown to maturity, and their potential fertility was estimated by observing the stainability of their pollen. The percent of pollen stainability in most of the hybrids was high enough to be judged partly or fully fertile. The polyploid complex composed of the species of Aster included in this study is comparable to certain other known complexes. Such complexes are similar in that the diploids are rather distinct morphologically and genetically, but they have contributed to the formation of a vast array of potentially interbreeding polyploids which lack sharp morphological definition. Most of the polyploids can be assigned to morphological categories that are more similar to related diploids than to other polyploids. Consequently, certain of the species have been delineated along vertical lines of relationship which may include several chromosome levels, In addition, some entities are retained as species which are known only as polypoids. which are relatively distinct and cannot be definitely donnested to a diploid species. This method is believed to be more indicative of relationship than would a system of grouping the entire polyploid assemblage in one highly polymorphic species, A phylogenetic chart of putative relationships among the taxa is presented, based largely on chromosome counts and morphology. The diploid entities are judged to be ancestral to, and thus more primitive than the polypoids, It was not possible to establish particular morphological traits as being more primitive or more advanced, Bathe it appears that evolution of morphological features has occurred at the diploid level, with subsequent polyploidy serving primarily to recombine the distinctive diploid features into various combinations. The information gained from the hybridization experiments contributed relative little to an understanding of natural affinities among these species, owing to the free crossability between the polyploids., Too few crosses were made involving diploids to determine accurately the degree of genetic incompatibility. Over 8000 herbarium specimens were examined in the process of delimiting species. The taxonomy section includes a key to the species, plus lists of synonyms, technical descriptions, citation of representative specimens, distribution maps, and brief discussions of the species. One new species, Aster idahoensis, is described in the thesis. Title: A biosystematic study in the genus Aster, section Aster, in western North America Author: Dean, Milton Lee A biosystematic investigation was undertaken in 15 species and three subspecies of the genus Aster, in western North America. Previous studies had been based entirely on external morphological features, and it was believed that much could be learned about the natural affinities of the taxa by exploring their cytological and genetical characteristics. More than 160 accessions were made during the course of the study. In the majority of cases, living rhizomes were transplanted in the greenhouse to provide material for making chromosome counts and hybridization experiments. Whenever possible, chromosomes were observed during meiotic divisions in microsporogenesis. One or more chromosome counts were made in 17 of the 18 taxa studied, 12 of which had not previously been examined cytologically. Ten taxa were found to include plants at two or more chromosome levels. The entire assemblage of species contains chromosome numbers on the basis of X = 8, with counts ranging from n = 8 to n = 48. Examples of aneuploidy, B-chromosomes, and meiotic irregularities were also discovered. A total of 383 artificial hybridizations was made among the species studied, resulting in the production of at least one fruit from 198 crosses. Most of the attempted crosses were interspecific, with the results indicating a striking lack of genetic incompatibility between the species at all polyploid levels. However, nearly all crosses involving diploid plants produced no fruits. First-generation hybrids of most species combinations were grown to maturity, and their potential fertility was estimated by observing the stainability of their pollen. The percent of pollen stainability in most of the hybrids was high enough to be judged partly or fully fertile. The polyploid complex composed of the species of Aster included in this study is comparable to certain other known complexes. Such complexes are similar in that the diploids are rather distinct morphologically and genetically, but they have contributed to the formation of a vast array of potentially interbreeding polyploids which lack sharp morphological definition. Most of the polyploids can be assigned to morphological categories that are more similar to related diploids than to other polyploids. Consequently, certain of the species have been delineated along vertical lines of relationship which may include several chromosome levels, In addition, some entities are retained as species which are known only as polypoids. which are relatively distinct and cannot be definitely donnested to a diploid species. This method is believed to be more indicative of relationship than would a system of grouping the entire polyploid assemblage in one highly polymorphic species, A phylogenetic chart of putative relationships among the taxa is presented, based largely on chromosome counts and morphology. The diploid entities are judged to be ancestral to, and thus more primitive than the polypoids, It was not possible to establish particular morphological traits as being more primitive or more advanced, Bathe it appears that evolution of morphological features has occurred at the diploid level, with subsequent polyploidy serving primarily to recombine the distinctive diploid features into various combinations. The information gained from the hybridization experiments contributed relative little to an understanding of natural affinities among these species, owing to the free crossability between the polyploids., Too few crosses were made involving diploids to determine accurately the degree of genetic incompatibility. Over 8000 herbarium specimens were examined in the process of delimiting species. The taxonomy section includes a key to the species, plus lists of synonyms, technical descriptions, citation of representative specimens, distribution maps, and brief discussions of the species. One new species, Aster idahoensis, is described in the thesis. Close

• 222. [Article] The Biology and ecology of weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana)

  Weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana) infest Kentucky bluegrass seed fields of eastern Oregon. Weeping alkaligrass is an introduced species from ...

  Citation × Citation Citation Abstract Copy Title: The Biology and ecology of weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana) Author: Tarasoff, Catherine Weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana) infest Kentucky bluegrass seed fields of eastern Oregon. Weeping alkaligrass is an introduced species from Eurasia, whereas Nuttall’s alkaligrass is native to semi arid environments of western North America. These species are often referred to collectively as ‘alkaligrass’; however, for farmers of eastern Oregon, there is concern as to which species may prove to be more troublesome. Germination experiments conducted to determine the seed biology attributes of the two species revealed that both species exhibit relatively long afterripening characteristics and viable seed for at least 1 year when dry stored. Once adequately afterripened, weeping alkaligrass had greater germination at most temperature combinations, in particular at constant temperatures. Weeping alkaligrass also was more tolerant of extreme high temperatures, as well as drought and salt conditions. Field experiments exploring the fitness of these two species on sodic versus normal soil types, found that weeping alkaligrass benefited from normal soil conditions growing larger and producing up to 4 times the seed. Weeping alkaligrass also was able to adjust to a lower solute potential under sodic soil conditions, and maintain a higher relative water content under normal soil conditions. For both species, a strong inhibitor to plant establishment was competing vegetation. Observational studies revealed that depressional areas increased the likelihood of establishment of both species. While Nuttall’s alkaligrass was positively associated with exchangeable sodium and negatively associated with exposed mineral soil, weeping alkaligrass exhibited the traits of a resource generalist, its abundance being negatively associated with competing vegetation. Results of a 2-year competition study comparing both species of alkaligrass with Kentucky bluegrass indicated that in year 1 Kentucky bluegrass grew slower than Nuttall’s alkaligrass, and to a lesser extent weeping alkaligrass. Yet, by year 2, the average Kentucky bluegrass plant was vastly larger than either of the alkaligrasses, in particular weeping alkaligrass. As well, during the first year of establishment, Kentucky bluegrass biomass was equally reduced by both species of alkaligrass more so than by itself. Results from the second year indicate that Kentucky bluegrass had much higher survival rates than the two species of alkaligrass, especially weeping alkaligrass. In year 2, the original planting density of Kentucky bluegrass was the strongest indicator of potential biomass for all three species. In a comparison between year 1 and year 2 biomass, it was apparent that while weeping alkaligrass exhibited high levels of mortality, the original planting densities strongly impacted the year 2 biomass accumulation of both Kentucky bluegrass and Nuttall’s alkaligrass. In conclusion, the traits of having wide ranging suitable germination conditions, a more dynamic phenotypic plasticity, increased fitness under agriculturally productive soils, traits of a resource generalist and lingering effects on the growth of both Nuttall’s alkaligrass and Kentucky bluegrass, may make the introduced weeping alkaligrass a species of greater concern than the native Nuttall’s alkaligrass for farmers of eastern Oregon. Title: The Biology and ecology of weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana) Author: Tarasoff, Catherine Weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia nuttalliana) infest Kentucky bluegrass seed fields of eastern Oregon. Weeping alkaligrass is an introduced species from Eurasia, whereas Nuttall’s alkaligrass is native to semi arid environments of western North America. These species are often referred to collectively as ‘alkaligrass’; however, for farmers of eastern Oregon, there is concern as to which species may prove to be more troublesome. Germination experiments conducted to determine the seed biology attributes of the two species revealed that both species exhibit relatively long afterripening characteristics and viable seed for at least 1 year when dry stored. Once adequately afterripened, weeping alkaligrass had greater germination at most temperature combinations, in particular at constant temperatures. Weeping alkaligrass also was more tolerant of extreme high temperatures, as well as drought and salt conditions. Field experiments exploring the fitness of these two species on sodic versus normal soil types, found that weeping alkaligrass benefited from normal soil conditions growing larger and producing up to 4 times the seed. Weeping alkaligrass also was able to adjust to a lower solute potential under sodic soil conditions, and maintain a higher relative water content under normal soil conditions. For both species, a strong inhibitor to plant establishment was competing vegetation. Observational studies revealed that depressional areas increased the likelihood of establishment of both species. While Nuttall’s alkaligrass was positively associated with exchangeable sodium and negatively associated with exposed mineral soil, weeping alkaligrass exhibited the traits of a resource generalist, its abundance being negatively associated with competing vegetation. Results of a 2-year competition study comparing both species of alkaligrass with Kentucky bluegrass indicated that in year 1 Kentucky bluegrass grew slower than Nuttall’s alkaligrass, and to a lesser extent weeping alkaligrass. Yet, by year 2, the average Kentucky bluegrass plant was vastly larger than either of the alkaligrasses, in particular weeping alkaligrass. As well, during the first year of establishment, Kentucky bluegrass biomass was equally reduced by both species of alkaligrass more so than by itself. Results from the second year indicate that Kentucky bluegrass had much higher survival rates than the two species of alkaligrass, especially weeping alkaligrass. In year 2, the original planting density of Kentucky bluegrass was the strongest indicator of potential biomass for all three species. In a comparison between year 1 and year 2 biomass, it was apparent that while weeping alkaligrass exhibited high levels of mortality, the original planting densities strongly impacted the year 2 biomass accumulation of both Kentucky bluegrass and Nuttall’s alkaligrass. In conclusion, the traits of having wide ranging suitable germination conditions, a more dynamic phenotypic plasticity, increased fitness under agriculturally productive soils, traits of a resource generalist and lingering effects on the growth of both Nuttall’s alkaligrass and Kentucky bluegrass, may make the introduced weeping alkaligrass a species of greater concern than the native Nuttall’s alkaligrass for farmers of eastern Oregon. Close

• 223. [Article] Prey-stage preference in phytoseiid mites

  Knowledge of how individual organisms behave in their environment can provide a greater understanding of population dynamics. In a predator-prey system, the choices made by predators when foraging for ...

  Citation × Citation Citation Abstract Copy Title: Prey-stage preference in phytoseiid mites Author: Blackwood, J. Scott Knowledge of how individual organisms behave in their environment can provide a greater understanding of population dynamics. In a predator-prey system, the choices made by predators when foraging for prey are important aspects of behavior. Particularly in the case of a stage-structured prey population, how the predator selects prey stages once a prey patch has been located can have implications for prey population growth, predator development and fecundity, and predator-prey system dynamics. Predaceous mites of the family Phytoseiidae are important biological control agents of Tetranychus spider mites in agricultural settings worldwide. Phytoseiid species range from specialists that require Tetranychus spider mite prey in order to develop and reproduce to generalist omnivores. In studies with 13 phytoseiid species, specialized species tended to prefer T. urticae eggs as prey or have no prey-stage preference while more generalist species tended to have no prey-stage preference or prey more often on mobile immatures. Further testing with a subset of these species suggested variability among species with regard to genetic and environmental influences on prey-stage preference. The specialist Phytoseiulus persimilis also preferred to forage and oviposit in patches containing egg-biased stage distributions rather than in adjacent mobile immature-biased patches. No benefits to offspring developing in either type of patch were found in terms of developmental time or subsequent adult fecundity. However, the results of both manipulative experiments and nonlinear population models indicated potential benefits of egg-biased predation in terms of current adult female fecundity, a less severe impact of predation on the prey population, and an increased number of predator descendents during the predator-prey interaction. Considering both subjective factors and discriminant analyses, prey-stage preference performed well as an indicator for the ecological classification of phytoseiid species. The classifications of four phytoseiid species occurring on apple in central and eastern Oregon, USA, were evaluated accordingly. Title: Prey-stage preference in phytoseiid mites Author: Blackwood, J. Scott Knowledge of how individual organisms behave in their environment can provide a greater understanding of population dynamics. In a predator-prey system, the choices made by predators when foraging for prey are important aspects of behavior. Particularly in the case of a stage-structured prey population, how the predator selects prey stages once a prey patch has been located can have implications for prey population growth, predator development and fecundity, and predator-prey system dynamics. Predaceous mites of the family Phytoseiidae are important biological control agents of Tetranychus spider mites in agricultural settings worldwide. Phytoseiid species range from specialists that require Tetranychus spider mite prey in order to develop and reproduce to generalist omnivores. In studies with 13 phytoseiid species, specialized species tended to prefer T. urticae eggs as prey or have no prey-stage preference while more generalist species tended to have no prey-stage preference or prey more often on mobile immatures. Further testing with a subset of these species suggested variability among species with regard to genetic and environmental influences on prey-stage preference. The specialist Phytoseiulus persimilis also preferred to forage and oviposit in patches containing egg-biased stage distributions rather than in adjacent mobile immature-biased patches. No benefits to offspring developing in either type of patch were found in terms of developmental time or subsequent adult fecundity. However, the results of both manipulative experiments and nonlinear population models indicated potential benefits of egg-biased predation in terms of current adult female fecundity, a less severe impact of predation on the prey population, and an increased number of predator descendents during the predator-prey interaction. Considering both subjective factors and discriminant analyses, prey-stage preference performed well as an indicator for the ecological classification of phytoseiid species. The classifications of four phytoseiid species occurring on apple in central and eastern Oregon, USA, were evaluated accordingly. Close

• 224. [Article] Interference dynamics in mixed red alder/Douglas-fir forests

  This study characterized the nature and dynamics of interference in mixed red alder (Alnus rubra Bong.)/Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands in the Pacific Northwest, USA. Long-term ...

  Citation × Citation Citation Abstract Copy Title: Interference dynamics in mixed red alder/Douglas-fir forests Author: D'Amato, Anthony W. This study characterized the nature and dynamics of interference in mixed red alder (Alnus rubra Bong.)/Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands in the Pacific Northwest, USA. Long-term spatial and tree measurements from the Cascade Head (CH) and H.J. Andrews (HJA) Experimental Forests in western Oregon and Delezene Creek (DC), Washington were utilized to investigate neighborhood and population-level measures of interference. Existing neighborhood and population-level measures of interference were modified to evaluate the intensity and importance of intra- and inter-specific interference. The relationship between relative growth rate and population-level and neighborhood interference were examined over 9 years at the CH and HJA study sites and 38 years at the DC study site. In general, the effects of intra-specific interacted with the effects of inter-specific interference to influence the relative growth rates of red alder and Douglas-fir at all of the sites. Performance of the interference measures as predictors of relative growth rates varied between species and with stand structure. In general, population-level indices were the best predictors of relative growth rates for the species with heights greater than the other interacting species over a given interval of time. In contrast, neighborhood indices were the best predictors of relative growth rates for the species with subordinate or equivalent tree heights to the dominant species over a given interval of time. These results were consistent for both species, all three study sites, and all measurement periods when interference occurred and suggest that the importance of neighborhood interference varies with the competitive status of a species. A conceptual model synthesizes the importance of neighborhood and population-level interference as a function of relative dominance of a species. In addition, the literature suggests that this model may also be appropriate for individuals within a population. Title: Interference dynamics in mixed red alder/Douglas-fir forests Author: D'Amato, Anthony W. This study characterized the nature and dynamics of interference in mixed red alder (Alnus rubra Bong.)/Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands in the Pacific Northwest, USA. Long-term spatial and tree measurements from the Cascade Head (CH) and H.J. Andrews (HJA) Experimental Forests in western Oregon and Delezene Creek (DC), Washington were utilized to investigate neighborhood and population-level measures of interference. Existing neighborhood and population-level measures of interference were modified to evaluate the intensity and importance of intra- and inter-specific interference. The relationship between relative growth rate and population-level and neighborhood interference were examined over 9 years at the CH and HJA study sites and 38 years at the DC study site. In general, the effects of intra-specific interacted with the effects of inter-specific interference to influence the relative growth rates of red alder and Douglas-fir at all of the sites. Performance of the interference measures as predictors of relative growth rates varied between species and with stand structure. In general, population-level indices were the best predictors of relative growth rates for the species with heights greater than the other interacting species over a given interval of time. In contrast, neighborhood indices were the best predictors of relative growth rates for the species with subordinate or equivalent tree heights to the dominant species over a given interval of time. These results were consistent for both species, all three study sites, and all measurement periods when interference occurred and suggest that the importance of neighborhood interference varies with the competitive status of a species. A conceptual model synthesizes the importance of neighborhood and population-level interference as a function of relative dominance of a species. In addition, the literature suggests that this model may also be appropriate for individuals within a population. Close

• 225. [Article] A comparative analysis of morphological, physiological, and biochemical adaptation to abiotic stress in intertidal porcelain crabs, genus Petrolisthes

  Organismal tolerance to abiotic environmental stresses contributes significantly to setting the distribution limits of organisms, as demonstrated by vertical zonation patterns in the marine intertidal ...

  Citation × Citation Citation Abstract Copy Title: A comparative analysis of morphological, physiological, and biochemical adaptation to abiotic stress in intertidal porcelain crabs, genus Petrolisthes Author: Stillman, Jonathon Harris Organismal tolerance to abiotic environmental stresses contributes significantly to setting the distribution limits of organisms, as demonstrated by vertical zonation patterns in the marine intertidal zone. In this thesis, the ultimate (evolutionary) and proximate (mechanistic) causes of tolerance to temperature and emersion stresses associated with the intertidal zone were examined using porcelain crabs, genus Petrolisthes. Species of Petrolisthes from intertidal and subtidal microhabitats of four biogeographic regions of the Eastern Pacific were used in phylogenetically-based comparative analyses of morphological, physiological, and biochemical adaptation to environmental stress. A phylogenetic tree based on the sequence of the 16sRNA gene was developed to facilitate these analyses. Organismal thermal tolerance limits are adapted to match maximal microhabitat temperatures. Acclimation of thermal tolerance limits suggests that temperate intertidal zone species are living close to their thermal maximum in nature. Respiratory responses to emersion vary among species from different vertical zones. Experimental examination of oxygen consumption rates and lactate accumulation during emersion suggests that intertidal species are able to respire in air using thin membranous regions on the ventral meral segments of their legs (leg membranes). Leg membrane size is positively correlated with body size across species, but not within a single species. Evolutionary analyses indicate that leg membranes may not have evolved for purposes of aerial respiration, but their presence may have allowed intertidal and subtidal species to achieve larger body sizes and higher metabolic rates. The thermal stabilities of an enzyme, lactate dehydrogenase (LDH), from 22 species of Petrolisthes varied widely, but were not correlated with maximal habitat temperatures. Comparative analyses did not indicate any evolutionary relationship between LDH thermal stability and microhabitat conditions. Experimental evidence suggests that interspecific differences in LDH stability are genetically based, and are due both to intrinsic properties of the LDH molecules and extrinsic protein stabilizers. Elucidation of the mechanism(s) of LDH stabilization in Petrolisthes may provide novel insight to the field of protein stabilization. These results studies suggest that individual traits may be subjected to differing levels of selection, and thus the analysis of environmental adaptation requires careful consideration of the biological significance of the traits being examined. Title: A comparative analysis of morphological, physiological, and biochemical adaptation to abiotic stress in intertidal porcelain crabs, genus Petrolisthes Author: Stillman, Jonathon Harris Organismal tolerance to abiotic environmental stresses contributes significantly to setting the distribution limits of organisms, as demonstrated by vertical zonation patterns in the marine intertidal zone. In this thesis, the ultimate (evolutionary) and proximate (mechanistic) causes of tolerance to temperature and emersion stresses associated with the intertidal zone were examined using porcelain crabs, genus Petrolisthes. Species of Petrolisthes from intertidal and subtidal microhabitats of four biogeographic regions of the Eastern Pacific were used in phylogenetically-based comparative analyses of morphological, physiological, and biochemical adaptation to environmental stress. A phylogenetic tree based on the sequence of the 16sRNA gene was developed to facilitate these analyses. Organismal thermal tolerance limits are adapted to match maximal microhabitat temperatures. Acclimation of thermal tolerance limits suggests that temperate intertidal zone species are living close to their thermal maximum in nature. Respiratory responses to emersion vary among species from different vertical zones. Experimental examination of oxygen consumption rates and lactate accumulation during emersion suggests that intertidal species are able to respire in air using thin membranous regions on the ventral meral segments of their legs (leg membranes). Leg membrane size is positively correlated with body size across species, but not within a single species. Evolutionary analyses indicate that leg membranes may not have evolved for purposes of aerial respiration, but their presence may have allowed intertidal and subtidal species to achieve larger body sizes and higher metabolic rates. The thermal stabilities of an enzyme, lactate dehydrogenase (LDH), from 22 species of Petrolisthes varied widely, but were not correlated with maximal habitat temperatures. Comparative analyses did not indicate any evolutionary relationship between LDH thermal stability and microhabitat conditions. Experimental evidence suggests that interspecific differences in LDH stability are genetically based, and are due both to intrinsic properties of the LDH molecules and extrinsic protein stabilizers. Elucidation of the mechanism(s) of LDH stabilization in Petrolisthes may provide novel insight to the field of protein stabilization. These results studies suggest that individual traits may be subjected to differing levels of selection, and thus the analysis of environmental adaptation requires careful consideration of the biological significance of the traits being examined. Close

• 226. [Article] Distribution of benthic fishes on the continental shelf and slope of the Oregon coast

  The 36 samples collected with a 22-foot semi-balloon shrimp trawl at depths from 40 to 1,829 meters off the central coast of Oregon between July 1961 and June 1962 provided preliminary data on the distribution, ...

  Citation × Citation Citation Abstract Copy Title: Distribution of benthic fishes on the continental shelf and slope of the Oregon coast Author: Day, Donald Stewart The 36 samples collected with a 22-foot semi-balloon shrimp trawl at depths from 40 to 1,829 meters off the central coast of Oregon between July 1961 and June 1962 provided preliminary data on the distribution, species composition, and associations of benthic fishes with respect to depth and sediment type. Sixty-seven species of bottom fishes representing 21 families were collected; 86 percent of the total number of fishes was composed of specimens from the families Pleuronectidae, Scorpaenidae, and Bothidae. Four communities of benthic fishes were found off the central Oregon coast within the depth interval from 40 to 1 ,829 meters. They were characterized by two or three dominant species, depth, and average sediment type. Ninety-seven percent of the species occurring in the communities showed high abundance in only one community. Some species also demonstrated size segregation by communities. The total number of species collected in progressively deeper communities was 26 (42 to 73 meters), 31 (119 to 199 meters), 20 (594 to 1,143 meters), and 9 (1,383 to 1,829 meters). Therefore the highest number of speciesoccurred in the community on the outer continental shelf and upper slope, while the lowest number of species occurred at the extreme depths on the continental slope. The number of species found on the continental shelf and slope were similar. Species inhabiting the continental slope, however, usually occurred over greater depth ranges. A comparison of the catches of the 22-foot shrimp trawl and a 94-foot fish trawl indicated that the small trawl used in this study retained comparatively few large fishes or semi-pelagic species. Fishes of the genus Sebastodes were grossly undersampled and probably comprised a major portion of the fish population, especially between the depths of 183 to 547 meters. Title: Distribution of benthic fishes on the continental shelf and slope of the Oregon coast Author: Day, Donald Stewart The 36 samples collected with a 22-foot semi-balloon shrimp trawl at depths from 40 to 1,829 meters off the central coast of Oregon between July 1961 and June 1962 provided preliminary data on the distribution, species composition, and associations of benthic fishes with respect to depth and sediment type. Sixty-seven species of bottom fishes representing 21 families were collected; 86 percent of the total number of fishes was composed of specimens from the families Pleuronectidae, Scorpaenidae, and Bothidae. Four communities of benthic fishes were found off the central Oregon coast within the depth interval from 40 to 1 ,829 meters. They were characterized by two or three dominant species, depth, and average sediment type. Ninety-seven percent of the species occurring in the communities showed high abundance in only one community. Some species also demonstrated size segregation by communities. The total number of species collected in progressively deeper communities was 26 (42 to 73 meters), 31 (119 to 199 meters), 20 (594 to 1,143 meters), and 9 (1,383 to 1,829 meters). Therefore the highest number of speciesoccurred in the community on the outer continental shelf and upper slope, while the lowest number of species occurred at the extreme depths on the continental slope. The number of species found on the continental shelf and slope were similar. Species inhabiting the continental slope, however, usually occurred over greater depth ranges. A comparison of the catches of the 22-foot shrimp trawl and a 94-foot fish trawl indicated that the small trawl used in this study retained comparatively few large fishes or semi-pelagic species. Fishes of the genus Sebastodes were grossly undersampled and probably comprised a major portion of the fish population, especially between the depths of 183 to 547 meters. Close

• 227. [Article] Biological studies on the hemoflagellates of Oregon marine fishes and their potential leech vectors

  Of 2,122 marine fishes belonging to 36 species collected in the vicinity of Newport, Oregon, 541 belonging to 8 species were infected with hemoflagellates. Four species of trypanosomes and three species of ...

  Citation × Citation Citation Abstract Copy Title: Biological studies on the hemoflagellates of Oregon marine fishes and their potential leech vectors Author: Burreson, Eugene Michael Of 2,122 marine fishes belonging to 36 species collected in the vicinity of Newport, Oregon, 541 belonging to 8 species were infected with hemoflagellates. Four species of trypanosomes and three species of cryptobias were found in offshore fishes, but no hemoflagellates were observed in fishes from Yaquina Bay. Trypanosoma pacifica was found in 177 of 1,102 Parophrys vetulus, 3 of 84 Citharichthys sordidus, and 1 of 35 Lyopsetta exilis, and survived in 10 other species after intraperitoneal injection. The host-specificity observed in nature was probably the result of selective feeding by the leech vector, possibly Oceanobdella sp. or Johanssonia sp. Division stages of T. pacifica were observed in the fish host and described. The growth rate of juvenile P. vetulus injected with T. pacifica was less than that of uninfected individuals for a 10 week period, after which the growth rates of the two groups were equivalent. Trypanosoma gargantua was found in 3 of 7 Raja binoculata and the vector was shown to be the leech Orientobdella sp. Two unidentified trypanosomes were observed, one from 21 of 1,102 P. vetulus, 24 of 303 Eopsetta jordani, and 6 of 61 Microstomus pacificus, and the other from 4 of 35 L. exilis. A small, active cryptobiid was found in 106 of 303 E. jordani, 51 of 1,102 P. vetulus, and a similar but larger flagellate in 9 of 35 L. exilis. After intraperitoneal injection flagellates from E. jordani did not survive in P. vetulus, but did survive in other flatfishes; flagellates from L. exilis survived in P. vetulus, but not E. jordani, indicating the possible presence of two species, one in E. jordani and one in P. vetulus and L. exilis. A larger, sluggish cryptobiid was found in 134 of 1,102 P. vetulus. An extremely large cryptobiid, grossly different morphologically from previously described species, was observed in 1 of 5 Scorpaenichthys marmoratus. The developmental cycle in the leech vector Malmiana sp. was described; the leech Trachelobdella sp. was also shown to be a potential vector. Leeches belonging to the following genera were collected during this study: Johanssonia, two species; Malmiana, three species; Trachelobdella, Oceanobdella, Orientobdella, and Ostreobdella. Of these, one species of Malmiana and one of Orientobdella were experimentally shown to be vectors of hemoflagellates. Title: Biological studies on the hemoflagellates of Oregon marine fishes and their potential leech vectors Author: Burreson, Eugene Michael Of 2,122 marine fishes belonging to 36 species collected in the vicinity of Newport, Oregon, 541 belonging to 8 species were infected with hemoflagellates. Four species of trypanosomes and three species of cryptobias were found in offshore fishes, but no hemoflagellates were observed in fishes from Yaquina Bay. Trypanosoma pacifica was found in 177 of 1,102 Parophrys vetulus, 3 of 84 Citharichthys sordidus, and 1 of 35 Lyopsetta exilis, and survived in 10 other species after intraperitoneal injection. The host-specificity observed in nature was probably the result of selective feeding by the leech vector, possibly Oceanobdella sp. or Johanssonia sp. Division stages of T. pacifica were observed in the fish host and described. The growth rate of juvenile P. vetulus injected with T. pacifica was less than that of uninfected individuals for a 10 week period, after which the growth rates of the two groups were equivalent. Trypanosoma gargantua was found in 3 of 7 Raja binoculata and the vector was shown to be the leech Orientobdella sp. Two unidentified trypanosomes were observed, one from 21 of 1,102 P. vetulus, 24 of 303 Eopsetta jordani, and 6 of 61 Microstomus pacificus, and the other from 4 of 35 L. exilis. A small, active cryptobiid was found in 106 of 303 E. jordani, 51 of 1,102 P. vetulus, and a similar but larger flagellate in 9 of 35 L. exilis. After intraperitoneal injection flagellates from E. jordani did not survive in P. vetulus, but did survive in other flatfishes; flagellates from L. exilis survived in P. vetulus, but not E. jordani, indicating the possible presence of two species, one in E. jordani and one in P. vetulus and L. exilis. A larger, sluggish cryptobiid was found in 134 of 1,102 P. vetulus. An extremely large cryptobiid, grossly different morphologically from previously described species, was observed in 1 of 5 Scorpaenichthys marmoratus. The developmental cycle in the leech vector Malmiana sp. was described; the leech Trachelobdella sp. was also shown to be a potential vector. Leeches belonging to the following genera were collected during this study: Johanssonia, two species; Malmiana, three species; Trachelobdella, Oceanobdella, Orientobdella, and Ostreobdella. Of these, one species of Malmiana and one of Orientobdella were experimentally shown to be vectors of hemoflagellates. Close

• 228. [Article] Agonistic behavior in three species of Microtus (M. canicaudus, M. oregoni, and M. townsendii)

  Agonistic behavior among three species of Microtus live-trapped near Corvallis, Oregon was recorded in order to interpret habitat segregation by the species in areas of syrnpatry. The method used to measure ...

  Citation × Citation Citation Abstract Copy Title: Agonistic behavior in three species of Microtus (M. canicaudus, M. oregoni, and M. townsendii) Author: Weil, James Wayne Agonistic behavior among three species of Microtus live-trapped near Corvallis, Oregon was recorded in order to interpret habitat segregation by the species in areas of syrnpatry. The method used to measure agonistic interaction was similar to that of Colvin (1970). Agonistic behavior was recorded under red light in a neutral circular arena. Two observers recorded the frequency and duration of 14 behavioral components on an Ester line event recorder for a ten minute trial. To be classified a winner in an agonistic encounter, an individual had to show more exploration, and display more approaches, attacks, and offense than its opponent. Based on these criteria, a trial could be termed fraternal, dominant-subordinate, no decision, or mutual avoidance, the last occurring when species remained separated approximately 180° and moved only to counter the others movements. In interspecific contests in which a winner could be determined, M. oregoni and M. canicaudus males were dominant to M. townsendii males (P < 0.001). Dominance in one-one contests involving homologous pairs of M. canicaudus versus M. oregoni could not be resolved (P > 0.05). The frequency of mutual avoidance by the three species in interand intraspecific encounters was greater when M. townsendii was involved and suggested that habitat spacing by the three species may depend on mutual avoidance as well as aggressive interaction. In a behavioral experiment performed in the laboratory to measure effects of agonistic interaction on habitat segregation, it was found that M. townsendii and M. oregoni were more gregarious than M. canicaudus. Log records indicated that males of all three species displayed more solitary behavioral patterns than females. Movement was significantly restricted when two species were paired in comparison to their controls (P < 0. 05). M. canicaudus males tended to be least restricted in their explorations and were most aggressive or intolerant toward other species, inflicting heavy casualties on M. oregoni in particular. Few instances of long-term interspecific associations developed. Those which did occur often involved labeled subordinate members of either species. Title: Agonistic behavior in three species of Microtus (M. canicaudus, M. oregoni, and M. townsendii) Author: Weil, James Wayne Agonistic behavior among three species of Microtus live-trapped near Corvallis, Oregon was recorded in order to interpret habitat segregation by the species in areas of syrnpatry. The method used to measure agonistic interaction was similar to that of Colvin (1970). Agonistic behavior was recorded under red light in a neutral circular arena. Two observers recorded the frequency and duration of 14 behavioral components on an Ester line event recorder for a ten minute trial. To be classified a winner in an agonistic encounter, an individual had to show more exploration, and display more approaches, attacks, and offense than its opponent. Based on these criteria, a trial could be termed fraternal, dominant-subordinate, no decision, or mutual avoidance, the last occurring when species remained separated approximately 180° and moved only to counter the others movements. In interspecific contests in which a winner could be determined, M. oregoni and M. canicaudus males were dominant to M. townsendii males (P < 0.001). Dominance in one-one contests involving homologous pairs of M. canicaudus versus M. oregoni could not be resolved (P > 0.05). The frequency of mutual avoidance by the three species in interand intraspecific encounters was greater when M. townsendii was involved and suggested that habitat spacing by the three species may depend on mutual avoidance as well as aggressive interaction. In a behavioral experiment performed in the laboratory to measure effects of agonistic interaction on habitat segregation, it was found that M. townsendii and M. oregoni were more gregarious than M. canicaudus. Log records indicated that males of all three species displayed more solitary behavioral patterns than females. Movement was significantly restricted when two species were paired in comparison to their controls (P < 0. 05). M. canicaudus males tended to be least restricted in their explorations and were most aggressive or intolerant toward other species, inflicting heavy casualties on M. oregoni in particular. Few instances of long-term interspecific associations developed. Those which did occur often involved labeled subordinate members of either species. Close

• 229. [Article] Experimental hybridization between Rana pretiosa pretiosa Baird and Girard and Rana cascadae Slater

  Experimental crosses between Rana pretiosa pretiosa Baird and Girard and Rana cascadae Slater, resulted in viable hybrids. Reciprocal differences at the time of fertilization are indicated. A high level ...

  Citation × Citation Citation Abstract Copy Title: Experimental hybridization between Rana pretiosa pretiosa Baird and Girard and Rana cascadae Slater Author: Haertel, John David Experimental crosses between Rana pretiosa pretiosa Baird and Girard and Rana cascadae Slater, resulted in viable hybrids. Reciprocal differences at the time of fertilization are indicated. A high level of success in producing viable hybrids can be obtained if Rana pretiosa pretiosa is the female of the parent species, The hybrid is characteristically intermediate to the parent species. The hybrid is quantitatively intermediate to the parent species in the characteristics of larval body width /tail depth ratios, developmental time, and mouth parts, Statistically treated larval body width/tail depth ratios of natural populations can be used to determine the amount and direction of natural hybridization between the species. Title: Experimental hybridization between Rana pretiosa pretiosa Baird and Girard and Rana cascadae Slater Author: Haertel, John David Experimental crosses between Rana pretiosa pretiosa Baird and Girard and Rana cascadae Slater, resulted in viable hybrids. Reciprocal differences at the time of fertilization are indicated. A high level of success in producing viable hybrids can be obtained if Rana pretiosa pretiosa is the female of the parent species, The hybrid is characteristically intermediate to the parent species. The hybrid is quantitatively intermediate to the parent species in the characteristics of larval body width /tail depth ratios, developmental time, and mouth parts, Statistically treated larval body width/tail depth ratios of natural populations can be used to determine the amount and direction of natural hybridization between the species. Close

• 230. [Article] Occurrence and relative abundance of small mammals associated with riparian and upland habitats along the Columbia River

  A small mammal inventory of occurrence and relative abundance was conducted in riparian and upland habitats in six segments along the lower Columbia River from the river mouth to McNary Dam (river mile ...

  Citation × Citation Citation Abstract Copy Title: Occurrence and relative abundance of small mammals associated with riparian and upland habitats along the Columbia River Author: Hinschberger, Mark Steven A small mammal inventory of occurrence and relative abundance was conducted in riparian and upland habitats in six segments along the lower Columbia River from the river mouth to McNary Dam (river mile 292) during 1974 and 1975 by removal trapping on standardized trap lines. Analysis of variance was used to compare capture per 100 trap-night indices of abundance of a species or group of species among habitats within a segment and among segments of the study area. Of the 59 species of small mammals purported to occur near the Columbia River, 39 were encountered. Many of the species not encountered. occur at elevations higher than the study area or are rare. Although 23 species were captured in standardized traps, the deer mouse (Peromyscus maniculatus) and vagrant shrew (Sorex vagrans) comprised 84.9 percent of the total catch. The deer mouse, the most abundant species, occurred in all 38 habitats except Russian olive (Elaeagnus angustifolia) and increased in abundance from west to east. Insectivores, mainly vagrant shrews, were most abundant in the west and decreased in abundance along the decreasing moisture gradient from west to east as did voles (Microtus spp.). Title: Occurrence and relative abundance of small mammals associated with riparian and upland habitats along the Columbia River Author: Hinschberger, Mark Steven A small mammal inventory of occurrence and relative abundance was conducted in riparian and upland habitats in six segments along the lower Columbia River from the river mouth to McNary Dam (river mile 292) during 1974 and 1975 by removal trapping on standardized trap lines. Analysis of variance was used to compare capture per 100 trap-night indices of abundance of a species or group of species among habitats within a segment and among segments of the study area. Of the 59 species of small mammals purported to occur near the Columbia River, 39 were encountered. Many of the species not encountered. occur at elevations higher than the study area or are rare. Although 23 species were captured in standardized traps, the deer mouse (Peromyscus maniculatus) and vagrant shrew (Sorex vagrans) comprised 84.9 percent of the total catch. The deer mouse, the most abundant species, occurred in all 38 habitats except Russian olive (Elaeagnus angustifolia) and increased in abundance from west to east. Insectivores, mainly vagrant shrews, were most abundant in the west and decreased in abundance along the decreasing moisture gradient from west to east as did voles (Microtus spp.). Close

• 231. [Article] The irradiation resistance of food pathogens contaminating seafoods

  Studies have been made to determine the limits of tolerance to gamma radiation for 15 cultures of the following bacterial species both in culture media and in irradiation-sterilized seafoods (crab-meat, halibut ...

  Citation × Citation Citation Abstract Copy Title: The irradiation resistance of food pathogens contaminating seafoods Author: Dutiyabodhi, Pisawat Studies have been made to determine the limits of tolerance to gamma radiation for 15 cultures of the following bacterial species both in culture media and in irradiation-sterilized seafoods (crab-meat, halibut and shrimp) inoculated with Salmonella (seven species), Shigella (three species), and one species each of Neisseria, Myco-bacterium, Esctrerichia, Proteus and Streptococcus. It was determined that the resistance dosages for the above mentioned bacterial species ranged from 2.0 x 10⁵ to 5.0 x 10⁵ rads. Salmonella schottmuelleri, Salmonella wichita, Salmonella typhosa and Escherichia coli were found to be the least sensitive to radiation, and therefore required the highest dosage. Shigella dysenteriae, Shigella paradysenteriae and Proteus vulgaris, which were most sensitive, required the lowest dosage. The cultures required dosages, in varying degree, between forementioned. It was found that radiation dosage for each of the bacterial species in culture media corresponded to that in seafoods upon irradiation. Attempts were made to use vitarnin K₅ as a radiation sensitizing agent for effective food preservation. The reeults did not indicate any obvious sensitizing effect of vitamin K₅ on Salmonella typhosa. Title: The irradiation resistance of food pathogens contaminating seafoods Author: Dutiyabodhi, Pisawat Studies have been made to determine the limits of tolerance to gamma radiation for 15 cultures of the following bacterial species both in culture media and in irradiation-sterilized seafoods (crab-meat, halibut and shrimp) inoculated with Salmonella (seven species), Shigella (three species), and one species each of Neisseria, Myco-bacterium, Esctrerichia, Proteus and Streptococcus. It was determined that the resistance dosages for the above mentioned bacterial species ranged from 2.0 x 10⁵ to 5.0 x 10⁵ rads. Salmonella schottmuelleri, Salmonella wichita, Salmonella typhosa and Escherichia coli were found to be the least sensitive to radiation, and therefore required the highest dosage. Shigella dysenteriae, Shigella paradysenteriae and Proteus vulgaris, which were most sensitive, required the lowest dosage. The cultures required dosages, in varying degree, between forementioned. It was found that radiation dosage for each of the bacterial species in culture media corresponded to that in seafoods upon irradiation. Attempts were made to use vitarnin K₅ as a radiation sensitizing agent for effective food preservation. The reeults did not indicate any obvious sensitizing effect of vitamin K₅ on Salmonella typhosa. Close

• 232. [Article] Habitat associations of bird communities in shrub-steppe and western juniper woodlands

  The encroachment of western juniper into mountain big sagebrush plant communities and the subsequent development of juniper stands results in significant changes in vegetation structure and complexity. ...

  Citation × Citation Citation Abstract Copy Title: Habitat associations of bird communities in shrub-steppe and western juniper woodlands Author: Reinkensmeyer, Daniel P. The encroachment of western juniper into mountain big sagebrush plant communities and the subsequent development of juniper stands results in significant changes in vegetation structure and complexity. This study described and compared vegetative structure and bird community measures among four cover types representing a broad range of structural stages among semi-arid, upland plant communities in central Oregon. Avian communities and vegetation were sampled in 4 vegetative structural stages (cover types), including: 1) post-burn grassland (<5years post-burn); 2) mountain big sagebrush-Idaho fescue shrub-steppe; 3) mid-successional western juniper; and 4) old-growth western juniper. The point count, or variable circular plot (VCP), method was used to survey birds in May and June of 1998 and 1999. Bird density estimates for each transect in each year, mean relative abundance, and species richness, evenness, and diversity were compared among cover types. Sixteen of 22 vegetation measurements were significantly different (P<_0.05) among the four cover types. Mean bird species richness was greatest in the old-growth and mid-successional juniper types, with means of 22.9 and 23.6 species transecf 1, respectively. Bird species diversity (H) was similar between the old-growth (H'=2.499) and mid-successional (H'=2.416) cover types. Mean species richness was lower in the grassland cover type (17.6 species transect ) and lowest in the shrub-steppe cover type (11.5 species transect 1). Bird species diversity was similar in grassland and shrubsteppe, H=1.820 and H=1.644. Habitat complexity was evaluated by comparing the diversity of coverage of plant structural types. Indices of habitat complexity were calculated for each transect by using physiognomic cover diversity (PCD). Bird species diversity was positively correlated with PCD (r2=0.535; P=0.0013). Total bird density was significantly greater in 1999 than in 1998 (P<_0.05). Total bird density was greatest in old-growth juniper (6.551 birds ha ) and lowest in post-burn grasslands (3.569 birds ha 1). Total bird density was similar in shrub-steppe and mid-successional juniper (5.968 and 5.542 birds ha-1, respectively). Old-growth juniper had the highest total densities of both tree and cavity nesters. Total density of ground nesting birds was greatest in the grassland type. Total density of shrub nesting species was highest in the shrub-steppe type. Species consistently detected within all four cover types were Empidonax spp. flycatchers, brown-headed cowbirds, and northern flickers. Species detected in juniper stands but not other types included chipping sparrows, mountain bluebirds, mountain chickadees, Cassin's finches, American robins, ash-throated flycatchers, and dark-eyed juncos. The most common species in the shrub-steppe were also present in mid-successional juniper, but at lower densities. Species composition in mid-successional juniper was a mixture of shrub-associated and tree-associated bird species. Many bird species that regularly occurred in old-growth juniper also occurred in mid-successional juniper, however, density and richness of shrub nesting species was lower in old-growth juniper. Mountain chickadees, Cassin's finches, chipping sparrows, brown-headed cowbirds, mountain bluebirds, and dark-eyed juncos, Empidonax spp. flycatchers, ashthroated flycatchers, and northern flickers were correlated with juniper canopy cover, canopy volume, total tree density, and average tree height. Vesper sparrows, western meadowlarks, green-tailed towhees, and horned larks were correlated with vertical density of herbaceous vegetation, total vertical density of all vegetative functional groups, and perennial grass cover. Brewer's sparrows, sage sparrows, sage thrashers, and horned larks were associated with total cover of all shrub species, cover of green rabbitbrush and sagebrush, vertical density of shrubs, and bare ground. In the absence of fire or direct management actions, the transition of mountain big sagebrush plant communities to juniper woodlands will likely result in decreased densities or loss of shrub nesting and sagebrush obligate birds. However, sites in the early stages of juniper transition, with an intact shrub component, may provide both shrub and tree-foliage nesting bird species with suitable breeding habitat. Old growth juniper stands provide both tree and cavity nesting species with breeding habitat, but shrub-nesting species will likely be absent or at very low densities because of low shrub cover. On a landscape level, a mixture of various ages of juniper stands, as well as juniper-free mountain big sagebrush and grassland will likely result in the greatest diversity of bird species. Title: Habitat associations of bird communities in shrub-steppe and western juniper woodlands Author: Reinkensmeyer, Daniel P. The encroachment of western juniper into mountain big sagebrush plant communities and the subsequent development of juniper stands results in significant changes in vegetation structure and complexity. This study described and compared vegetative structure and bird community measures among four cover types representing a broad range of structural stages among semi-arid, upland plant communities in central Oregon. Avian communities and vegetation were sampled in 4 vegetative structural stages (cover types), including: 1) post-burn grassland (<5years post-burn); 2) mountain big sagebrush-Idaho fescue shrub-steppe; 3) mid-successional western juniper; and 4) old-growth western juniper. The point count, or variable circular plot (VCP), method was used to survey birds in May and June of 1998 and 1999. Bird density estimates for each transect in each year, mean relative abundance, and species richness, evenness, and diversity were compared among cover types. Sixteen of 22 vegetation measurements were significantly different (P<_0.05) among the four cover types. Mean bird species richness was greatest in the old-growth and mid-successional juniper types, with means of 22.9 and 23.6 species transecf 1, respectively. Bird species diversity (H) was similar between the old-growth (H'=2.499) and mid-successional (H'=2.416) cover types. Mean species richness was lower in the grassland cover type (17.6 species transect ) and lowest in the shrub-steppe cover type (11.5 species transect 1). Bird species diversity was similar in grassland and shrubsteppe, H=1.820 and H=1.644. Habitat complexity was evaluated by comparing the diversity of coverage of plant structural types. Indices of habitat complexity were calculated for each transect by using physiognomic cover diversity (PCD). Bird species diversity was positively correlated with PCD (r2=0.535; P=0.0013). Total bird density was significantly greater in 1999 than in 1998 (P<_0.05). Total bird density was greatest in old-growth juniper (6.551 birds ha ) and lowest in post-burn grasslands (3.569 birds ha 1). Total bird density was similar in shrub-steppe and mid-successional juniper (5.968 and 5.542 birds ha-1, respectively). Old-growth juniper had the highest total densities of both tree and cavity nesters. Total density of ground nesting birds was greatest in the grassland type. Total density of shrub nesting species was highest in the shrub-steppe type. Species consistently detected within all four cover types were Empidonax spp. flycatchers, brown-headed cowbirds, and northern flickers. Species detected in juniper stands but not other types included chipping sparrows, mountain bluebirds, mountain chickadees, Cassin's finches, American robins, ash-throated flycatchers, and dark-eyed juncos. The most common species in the shrub-steppe were also present in mid-successional juniper, but at lower densities. Species composition in mid-successional juniper was a mixture of shrub-associated and tree-associated bird species. Many bird species that regularly occurred in old-growth juniper also occurred in mid-successional juniper, however, density and richness of shrub nesting species was lower in old-growth juniper. Mountain chickadees, Cassin's finches, chipping sparrows, brown-headed cowbirds, mountain bluebirds, and dark-eyed juncos, Empidonax spp. flycatchers, ashthroated flycatchers, and northern flickers were correlated with juniper canopy cover, canopy volume, total tree density, and average tree height. Vesper sparrows, western meadowlarks, green-tailed towhees, and horned larks were correlated with vertical density of herbaceous vegetation, total vertical density of all vegetative functional groups, and perennial grass cover. Brewer's sparrows, sage sparrows, sage thrashers, and horned larks were associated with total cover of all shrub species, cover of green rabbitbrush and sagebrush, vertical density of shrubs, and bare ground. In the absence of fire or direct management actions, the transition of mountain big sagebrush plant communities to juniper woodlands will likely result in decreased densities or loss of shrub nesting and sagebrush obligate birds. However, sites in the early stages of juniper transition, with an intact shrub component, may provide both shrub and tree-foliage nesting bird species with suitable breeding habitat. Old growth juniper stands provide both tree and cavity nesting species with breeding habitat, but shrub-nesting species will likely be absent or at very low densities because of low shrub cover. On a landscape level, a mixture of various ages of juniper stands, as well as juniper-free mountain big sagebrush and grassland will likely result in the greatest diversity of bird species. Close

• 233. [Article] Tree crown ratio models for multi-species and multi-layered stands of southeastern British Columbia

  This is the publisher’s final pdf. The published article is copyrighted by Canadian Institute of Forestry and can be found at: http://pubs.cif-ifc.org/journal/tfc.

  Citation × Citation Citation Abstract Copy Title: Tree crown ratio models for multi-species and multi-layered stands of southeastern British Columbia Author: Temesgen, Hailemariam, LeMay, Valerie, Mitchell, Stephen J. This is the publisher’s final pdf. The published article is copyrighted by Canadian Institute of Forestry and can be found at: http://pubs.cif-ifc.org/journal/tfc. Title: Tree crown ratio models for multi-species and multi-layered stands of southeastern British Columbia Author: Temesgen, Hailemariam, LeMay, Valerie, Mitchell, Stephen J. This is the publisher’s final pdf. The published article is copyrighted by Canadian Institute of Forestry and can be found at: http://pubs.cif-ifc.org/journal/tfc. Close

• 234. [Article] Uptake and retention of technetuim [i.e. technetium] by two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula

  The patterns of uptake, retention, and tissue distribution of ⁹⁵mTc in two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula have been investigated. The animals were ...

  Citation × Citation Citation Abstract Copy Title: Uptake and retention of technetuim [i.e. technetium] by two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula Author: McKenzie-Carter, Michael A. The patterns of uptake, retention, and tissue distribution of ⁹⁵mTc in two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula have been investigated. The animals were chronically exposed in water to which sodium pertechnetate had been added. Final whole-body concentration ratios (CR) obtained were 1.6 and 41 for the crayfish and the snail, respectively. Following the uptake study the animals were placed in fresh non-radioactive water for a retention study. Two-phase retention patterns were observed in both species. The long-lived component of the crayfish curve contained 82% of the body burden, while that of the snail contained 90%. Biological half-lives for the long-lived retention components were determined to be 141 days and 120 days for the crayfish and the snail, respectively. Tissue distribution data showed that 79-100% of the crayfish whole-body activity was shared between the exoskeleton and the digestive gland at all times, whereas the soft tissues of the snail contained 82-96% of the whole-body activity. Data from these two species are similar to past research results that indicated uptake of Tc is highly variable among different species. The final crayfish CR value obtained is several orders of magnitude below those reported for the taxonomically-related lobster, and is among the lowest values reported for freshwater invertebrates. Uptake by J. silicula indicates a more significant accumulation of Tc, however a high degree of variation between identical animals was observed. This study suggests that Tc contamination in the two study species would not pose a significant health problem to humans. The crayfish represents a potential direct pathway to man, however the degree to which P. leniusculus concentrated Tc indicates that this would not be a health hazard. The higher degree of concentration by the snail represents a potential indirect hazard. Further studies investigating such factors as variability in individual uptake and the efficiency of trophic transfer of Tc need to be undertaken in order to accurately assess the impact of Tc releases. Title: Uptake and retention of technetuim [i.e. technetium] by two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula Author: McKenzie-Carter, Michael A. The patterns of uptake, retention, and tissue distribution of ⁹⁵mTc in two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula have been investigated. The animals were chronically exposed in water to which sodium pertechnetate had been added. Final whole-body concentration ratios (CR) obtained were 1.6 and 41 for the crayfish and the snail, respectively. Following the uptake study the animals were placed in fresh non-radioactive water for a retention study. Two-phase retention patterns were observed in both species. The long-lived component of the crayfish curve contained 82% of the body burden, while that of the snail contained 90%. Biological half-lives for the long-lived retention components were determined to be 141 days and 120 days for the crayfish and the snail, respectively. Tissue distribution data showed that 79-100% of the crayfish whole-body activity was shared between the exoskeleton and the digestive gland at all times, whereas the soft tissues of the snail contained 82-96% of the whole-body activity. Data from these two species are similar to past research results that indicated uptake of Tc is highly variable among different species. The final crayfish CR value obtained is several orders of magnitude below those reported for the taxonomically-related lobster, and is among the lowest values reported for freshwater invertebrates. Uptake by J. silicula indicates a more significant accumulation of Tc, however a high degree of variation between identical animals was observed. This study suggests that Tc contamination in the two study species would not pose a significant health problem to humans. The crayfish represents a potential direct pathway to man, however the degree to which P. leniusculus concentrated Tc indicates that this would not be a health hazard. The higher degree of concentration by the snail represents a potential indirect hazard. Further studies investigating such factors as variability in individual uptake and the efficiency of trophic transfer of Tc need to be undertaken in order to accurately assess the impact of Tc releases. Close

• 235. [Article] Controlling woody vegetation in wetland prairies, 1994-2001

  Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining ...

  Citation × Citation Citation Abstract Copy Title: Controlling woody vegetation in wetland prairies, 1994-2001 Author: Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand-removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After four treatments periods (1994, 1996, 1998, and 2000) the following patterns emerged: • Woody species Burning and hand-removal of woody plants every two years consistently decreased the cover of woody species, even with a gradual increase in the controls to over double 1994 levels. The change in woody cover after mowing with removal of cut material was not significantly different from that in the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species None of the treatments had a significant effect after four treatment periods on the proportional change in cover or in number of inflorescences of Deschampsia cespitosa, although the change in number of inflorescences was consistently less than that in the control, including a significant decrease with burning in 1997. As a group, native graminoid species showed no significant differences in flowering response to treatments during any of the four treatment periods. However, burning and mowing consistently promoted flowering of Juncus tenuis. The cover of native forbs as a group was not significantly different from that of the control, with the exception of 1997, where cover increased with burning and hand-removal. Even though native forbs as a group have generally not shown significant differences, individual native forb species have shown positive responses to treatments: Sidalcea cusickii, spp. purpurea, Eriophyllum lanatum, and Sisyrinchium idahoensis. • Non-native herbaceous species Both hand-removal and mowing promoted flowering of non-native graminoids as a group. In contrast, burning maintained levels of flowering of non-native graminoids similar to that of the controls. Cover of non-native forbs as a group showed no significant treatment differences except for 1997, in which significant reductions in cover occurred after burning and hand-removal. The results to date show that prescribed burning is the best option of the three tested management treatments for achieving the restoration goals for native wetland prairies. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment should be avoided. Title: Controlling woody vegetation in wetland prairies, 1994-2001 Author: Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand-removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After four treatments periods (1994, 1996, 1998, and 2000) the following patterns emerged: • Woody species Burning and hand-removal of woody plants every two years consistently decreased the cover of woody species, even with a gradual increase in the controls to over double 1994 levels. The change in woody cover after mowing with removal of cut material was not significantly different from that in the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species None of the treatments had a significant effect after four treatment periods on the proportional change in cover or in number of inflorescences of Deschampsia cespitosa, although the change in number of inflorescences was consistently less than that in the control, including a significant decrease with burning in 1997. As a group, native graminoid species showed no significant differences in flowering response to treatments during any of the four treatment periods. However, burning and mowing consistently promoted flowering of Juncus tenuis. The cover of native forbs as a group was not significantly different from that of the control, with the exception of 1997, where cover increased with burning and hand-removal. Even though native forbs as a group have generally not shown significant differences, individual native forb species have shown positive responses to treatments: Sidalcea cusickii, spp. purpurea, Eriophyllum lanatum, and Sisyrinchium idahoensis. • Non-native herbaceous species Both hand-removal and mowing promoted flowering of non-native graminoids as a group. In contrast, burning maintained levels of flowering of non-native graminoids similar to that of the controls. Cover of non-native forbs as a group showed no significant treatment differences except for 1997, in which significant reductions in cover occurred after burning and hand-removal. The results to date show that prescribed burning is the best option of the three tested management treatments for achieving the restoration goals for native wetland prairies. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment should be avoided. Close

• 236. [Article] Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters

  Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. ...

  Citation × Citation Citation Abstract Copy Title: Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters Author: Strecker, Angela L., Olden, Julian D. Year: 2014 Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. Title: Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters Author: Strecker, Angela L., Olden, Julian D. Year: 2014 Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. Close

• 237. [Article] Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings

  Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and ...

  Citation × Citation Citation Abstract Copy Title: Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings Author: Peterson, Kate, Calabria, Lalita M., Miller, Jesse E.D., Brown-Clay, Jesse Year: 2017 Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and forest health. Stand age has been implicated as a key factor in driving epiphytic species diversity and community composition. However, understanding the influence of substrate age, independent of the many confounding variables that affect live and dead wood substrates in a forest habitat, can be difficult. To test the hypothesis that substrate age has distinct effects on lichen community assembly independent of surface area, we sampled communities of calicioid lichens and fungi growing on wooden buildings that ranged from 2 to 82 years old. We found a total of 17 species, with a strong positive correlation between species richness and substrate age. We also tested the effects of surface area on species richness and found no relationship between the two variables. Our results indicate that substrate age influenced community composition; non-lichenized calicioid species acted as early colonizers and six calicioid species were recorded only on the oldest substrate. Old-growth associate species were found on substrates of varying ages, implying that additional variables may also be responsible for the colonization of old-growth associate species. Copyright © 2017 by The American Bryological and Lichenological Society, Inc. Title: Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings Author: Peterson, Kate, Calabria, Lalita M., Miller, Jesse E.D., Brown-Clay, Jesse Year: 2017 Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and forest health. Stand age has been implicated as a key factor in driving epiphytic species diversity and community composition. However, understanding the influence of substrate age, independent of the many confounding variables that affect live and dead wood substrates in a forest habitat, can be difficult. To test the hypothesis that substrate age has distinct effects on lichen community assembly independent of surface area, we sampled communities of calicioid lichens and fungi growing on wooden buildings that ranged from 2 to 82 years old. We found a total of 17 species, with a strong positive correlation between species richness and substrate age. We also tested the effects of surface area on species richness and found no relationship between the two variables. Our results indicate that substrate age influenced community composition; non-lichenized calicioid species acted as early colonizers and six calicioid species were recorded only on the oldest substrate. Old-growth associate species were found on substrates of varying ages, implying that additional variables may also be responsible for the colonization of old-growth associate species. Copyright © 2017 by The American Bryological and Lichenological Society, Inc. Close

• 238. [Article] Educating Pacific Northwest Campers on the Risk of Spreading Invasive Forest Pests through Firewood: Developing a Mental Model

  2011

  Citation × Citation Citation Abstract Copy Title: Educating Pacific Northwest Campers on the Risk of Spreading Invasive Forest Pests through Firewood: Developing a Mental Model Author: Runberg, Damon 2011 Title: Educating Pacific Northwest Campers on the Risk of Spreading Invasive Forest Pests through Firewood: Developing a Mental Model Author: Runberg, Damon 2011 Close

• 239. [Article] Comparative hydraulic architecture of tropical tree species representing a range of successional stages and wood density

  The original publication is available at www.springerlink.com.

  Citation × Citation Citation Abstract Copy Title: Comparative hydraulic architecture of tropical tree species representing a range of successional stages and wood density Author: Meinzer, F. C., Woodruff, D. R., Lachenbruch, B., Domec, J.-C., McCulloh, K. A., Voelker, S. L., Sperry, J. S. The original publication is available at www.springerlink.com. Title: Comparative hydraulic architecture of tropical tree species representing a range of successional stages and wood density Author: Meinzer, F. C., Woodruff, D. R., Lachenbruch, B., Domec, J.-C., McCulloh, K. A., Voelker, S. L., Sperry, J. S. The original publication is available at www.springerlink.com. Close

• 240. [Article] Sources of Variation in the Self-Thinning Boundary Line for Three Species with Varying Levels of Shade Tolerance

  The species self-thinning boundary line has been widely analyzed with a variety of statistical techniques. Most previous studies in the forestry literature have reported that the relationship does not ...

  Citation × Citation Citation Abstract Copy Title: Sources of Variation in the Self-Thinning Boundary Line for Three Species with Varying Levels of Shade Tolerance Author: Temesgen, Hailemariam, Weiskittel, Aaron, Gould, Peter The species self-thinning boundary line has been widely analyzed with a variety of statistical techniques. Most previous studies in the forestry literature have reported that the relationship does not differ across a range of stand and site factors, but these studies have primarily used statistical techniques that make model fitting subjective or interpretation of covariate significance difficult. There is growing evidence that the use of stochastic frontier analysis is an effective statistical means for objectively fitting the species self-thinning boundary line, offering the opportunity to test the influence of additional covariates. Using extensive even-aged coastal Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco), western hemlock (Tsuga heterophylla), and red alder (Alnus rubra Bong.) data sets in the Pacific Northwest, we examined the assumption that the intercept and slope of the species self-thinning boundary line are insensitive to stand and site factors. Likelihood ratio tests indicated that site index, stand origin (natural versus planted), and purity (proportion of basal area in the primary species) significantly influenced the species self-thinning boundary line intercept for each of the species examined in this study. In Douglas-fir and western hemlock, the slope of the self-thinning boundary was also dependent on stand origin as well as site index in the case of Douglas-fir. Fertilization did not significantly influence the intercept or slope of the species self-thinning line for Douglas-fir and western hemlock. In addition, the inclusion of site aspect and dryness index marginally improved the red alder model of self-thinning, but neither site soil nor climatic variables improved the models for western hemlock and Douglas-fir. Thus, the species self-thinning boundary line can vary significantly among stands, and its variation is driven by several distinct factors; stochastic frontier analysis is an effective tool for identifying these factors. Title: Sources of Variation in the Self-Thinning Boundary Line for Three Species with Varying Levels of Shade Tolerance Author: Temesgen, Hailemariam, Weiskittel, Aaron, Gould, Peter The species self-thinning boundary line has been widely analyzed with a variety of statistical techniques. Most previous studies in the forestry literature have reported that the relationship does not differ across a range of stand and site factors, but these studies have primarily used statistical techniques that make model fitting subjective or interpretation of covariate significance difficult. There is growing evidence that the use of stochastic frontier analysis is an effective statistical means for objectively fitting the species self-thinning boundary line, offering the opportunity to test the influence of additional covariates. Using extensive even-aged coastal Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco), western hemlock (Tsuga heterophylla), and red alder (Alnus rubra Bong.) data sets in the Pacific Northwest, we examined the assumption that the intercept and slope of the species self-thinning boundary line are insensitive to stand and site factors. Likelihood ratio tests indicated that site index, stand origin (natural versus planted), and purity (proportion of basal area in the primary species) significantly influenced the species self-thinning boundary line intercept for each of the species examined in this study. In Douglas-fir and western hemlock, the slope of the self-thinning boundary was also dependent on stand origin as well as site index in the case of Douglas-fir. Fertilization did not significantly influence the intercept or slope of the species self-thinning line for Douglas-fir and western hemlock. In addition, the inclusion of site aspect and dryness index marginally improved the red alder model of self-thinning, but neither site soil nor climatic variables improved the models for western hemlock and Douglas-fir. Thus, the species self-thinning boundary line can vary significantly among stands, and its variation is driven by several distinct factors; stochastic frontier analysis is an effective tool for identifying these factors. Close

• 241. [Article] Using Mitogenomic and Nuclear Ribosomal Sequence Data to Investigate the Phylogeny of the Xiphinema americanum Species Complex

  This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/.

  Citation × Citation Citation Abstract Copy Title: Using Mitogenomic and Nuclear Ribosomal Sequence Data to Investigate the Phylogeny of the Xiphinema americanum Species Complex Author: Peetz, Amy, Zasada, Inga A., Denver, Dee R., Howe, Dana K., Wilhelm, Larry J., Cheam, Daravuth, Smythe, Ashleigh B. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Title: Using Mitogenomic and Nuclear Ribosomal Sequence Data to Investigate the Phylogeny of the Xiphinema americanum Species Complex Author: Peetz, Amy, Zasada, Inga A., Denver, Dee R., Howe, Dana K., Wilhelm, Larry J., Cheam, Daravuth, Smythe, Ashleigh B. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Close

• 242. [Article] Phylogeny and taxonomy of parasites of the Multivalvulida (myxoza:myxosporea) based on comparative DNA sequence analysis

  Relationships among myxozoan parasites of the order Multivalvulida were examined through comparative DNA sequence analysis. Members of this group of parasites is known for the damaging effects they have ...

  Citation × Citation Citation Abstract Copy Title: Phylogeny and taxonomy of parasites of the Multivalvulida (myxoza:myxosporea) based on comparative DNA sequence analysis Author: Whipps, Christopher Michael Relationships among myxozoan parasites of the order Multivalvulida were examined through comparative DNA sequence analysis. Members of this group of parasites is known for the damaging effects they have on their fish hosts, especially commercially important species. Most species infect muscle, where they form cysts and many release proteolytic enzymes. Morphological and molecular analyses were conducted on isolates of the widely distributed Kudoa thyrsites to determine if this species was actually an assemblage of several parasite species in a variety of host species. Molecular analyses employed small subunit (SSU) ribosomal DNA sequences and for the first time, myxozoan internal transcribed spacer (ITS) sequences. Genetically distinct populations of K. thyrsites do exist on a broad geographic scale, but it would be inappropriate to consider these groups as different species at this time for the following reasons: there are no clear morphological distinctions that correspond with the observed molecular differences and impacts of the parasite (i.e., soft flesh) are no different in any of the locations. Therefore, although genetic data may suggest that subdivision of K thyrsites is warranted, such subdivision would only generate confusion as DNA sequence analyses would be required for future identifications of these groups. Species boundaries must be defined not only by molecular analyses but by measurable phenotypic differences, as was the case with species similar to K thyrsites; K minithyrsites and Kudoa lateolabracis. At the interspecific level, phylogenetic analyses based on SSU, and for the first time, myxozoan large subunit ribosomal DNA, indicated that a revision of order Multivalvulida taxonomy was warranted. The descriptive generic names Pentacapsula, Hexacapsula and Septemcapsula proved to be artificial groupings of multivalvulid species. Thus, these genera were synonymized with Kudoa. The aim of scientific classification is to organize phena in a manner that not only facilitates communication, but also reflects the shared evolutionary history of these organisms. Clearly, placing members of the Kudoidae into different genera and even families based on a single characteristic of their spores (i.e., valve number) is a poor representation of their close relationship. Title: Phylogeny and taxonomy of parasites of the Multivalvulida (myxoza:myxosporea) based on comparative DNA sequence analysis Author: Whipps, Christopher Michael Relationships among myxozoan parasites of the order Multivalvulida were examined through comparative DNA sequence analysis. Members of this group of parasites is known for the damaging effects they have on their fish hosts, especially commercially important species. Most species infect muscle, where they form cysts and many release proteolytic enzymes. Morphological and molecular analyses were conducted on isolates of the widely distributed Kudoa thyrsites to determine if this species was actually an assemblage of several parasite species in a variety of host species. Molecular analyses employed small subunit (SSU) ribosomal DNA sequences and for the first time, myxozoan internal transcribed spacer (ITS) sequences. Genetically distinct populations of K. thyrsites do exist on a broad geographic scale, but it would be inappropriate to consider these groups as different species at this time for the following reasons: there are no clear morphological distinctions that correspond with the observed molecular differences and impacts of the parasite (i.e., soft flesh) are no different in any of the locations. Therefore, although genetic data may suggest that subdivision of K thyrsites is warranted, such subdivision would only generate confusion as DNA sequence analyses would be required for future identifications of these groups. Species boundaries must be defined not only by molecular analyses but by measurable phenotypic differences, as was the case with species similar to K thyrsites; K minithyrsites and Kudoa lateolabracis. At the interspecific level, phylogenetic analyses based on SSU, and for the first time, myxozoan large subunit ribosomal DNA, indicated that a revision of order Multivalvulida taxonomy was warranted. The descriptive generic names Pentacapsula, Hexacapsula and Septemcapsula proved to be artificial groupings of multivalvulid species. Thus, these genera were synonymized with Kudoa. The aim of scientific classification is to organize phena in a manner that not only facilitates communication, but also reflects the shared evolutionary history of these organisms. Clearly, placing members of the Kudoidae into different genera and even families based on a single characteristic of their spores (i.e., valve number) is a poor representation of their close relationship. Close

• 243. [Article] Assemblages of groundfish caught using commercial fishing strategies off the coasts of Oregon and Washington from 1985-1987

  The groundfish trawl fishery operating off the coasts of Oregon and Washington 1985-1987 caught six major assemblages of species which could be treated as units in developing mixed-species management plans. ...

  Citation × Citation Citation Abstract Copy Title: Assemblages of groundfish caught using commercial fishing strategies off the coasts of Oregon and Washington from 1985-1987 Author: Rogers, Jean Beyer The groundfish trawl fishery operating off the coasts of Oregon and Washington 1985-1987 caught six major assemblages of species which could be treated as units in developing mixed-species management plans. Eighty-one percent of the tows observed on commercial vessels were consistently placed in one of the assemblage designations using three multivariate techniques. Two of the assemblages were dominated by a single species, pink shrimp (Pandalus jordani) or widow rockfish (Sebastes entomelas). The other assemblages identified were: a deepwater rockfish assemblage, a deepwater Dover sole assemblage, a nearshore mixed-species assemblage, and a bottom rockfish assemblage. The assemblage designations of the consistently placed tows were predicted with an estimated 85% average accuracy using discriminant functions based on the gear used and bottom depth fished. Fishermen had different targets (intended catch) for each assemblage caught. The mixed-species assemblages had several targets, representing at least some of the dominant species in the assemblage. Targeting and discarding information indicated that fishermen did not always intend to catch the species together; there were unintentional or unavoidable catches of all the major species except for shrimp in the shrimp assemblage. Discarding occurred in all the assemblages, primarily due to unmarketable species or fish that were too small to market. Monitoring the assemblages over time could be accomplished by using the defined strategies with logbook data, particularly if the large and small rockfish categories were used to consistently separate shelf and deepwater rockfish. The defined strategies could not effectively predict the research cruise assemblages or catches; research data do not accurately describe commercial catches. Title: Assemblages of groundfish caught using commercial fishing strategies off the coasts of Oregon and Washington from 1985-1987 Author: Rogers, Jean Beyer The groundfish trawl fishery operating off the coasts of Oregon and Washington 1985-1987 caught six major assemblages of species which could be treated as units in developing mixed-species management plans. Eighty-one percent of the tows observed on commercial vessels were consistently placed in one of the assemblage designations using three multivariate techniques. Two of the assemblages were dominated by a single species, pink shrimp (Pandalus jordani) or widow rockfish (Sebastes entomelas). The other assemblages identified were: a deepwater rockfish assemblage, a deepwater Dover sole assemblage, a nearshore mixed-species assemblage, and a bottom rockfish assemblage. The assemblage designations of the consistently placed tows were predicted with an estimated 85% average accuracy using discriminant functions based on the gear used and bottom depth fished. Fishermen had different targets (intended catch) for each assemblage caught. The mixed-species assemblages had several targets, representing at least some of the dominant species in the assemblage. Targeting and discarding information indicated that fishermen did not always intend to catch the species together; there were unintentional or unavoidable catches of all the major species except for shrimp in the shrimp assemblage. Discarding occurred in all the assemblages, primarily due to unmarketable species or fish that were too small to market. Monitoring the assemblages over time could be accomplished by using the defined strategies with logbook data, particularly if the large and small rockfish categories were used to consistently separate shelf and deepwater rockfish. The defined strategies could not effectively predict the research cruise assemblages or catches; research data do not accurately describe commercial catches. Close

• 244. [Article] Marine resource surveys on the continental shelf off Oregon, 1971-74 : completion report July 1, 1971 to June 30, 1975

  Groundfish surveys off Oregon were conducted over a four year period (1971-74) between the Columbia River and Cape Blanco. Primary purpose of the surveys was to obtain estimates of biomass of important ...

  Citation × Citation Citation Abstract Copy Title: Marine resource surveys on the continental shelf off Oregon, 1971-74 : completion report July 1, 1971 to June 30, 1975 Author: Forsberg, Brent O., United States. National Marine Fisheries Service, Ten Eyck, Neil, Demory, Robert L., Hosie, Michael J. Groundfish surveys off Oregon were conducted over a four year period (1971-74) between the Columbia River and Cape Blanco. Primary purpose of the surveys was to obtain estimates of biomass of important groundfish occupying the continental shelf and upper continental slope. Survey design was based on a 5 x 5 N mi grid with a random starting point. This resulted in trawling intensity of about 1 tow per 25 N mi² of trawlable bottom. Samples for age, size and sex composition were taken from important species of flatfish. Weights of all species caught were obtained. Estimates of biomass (a11 species) were 283,750 metric tons in 1971-72 and 235,117 metric tons in 1973-74. Pacific hake was the most abundant species followed by Dover sole. Estimates of potential yield were determined for five species of flatfish. Data indicate that only petrale sole are being fully exploited. Increased yield could be obtained without increasing fishing effort if economic conditions were such that the species caught were more completely utilized. Distribution of major species is depicted by catch maps. Distribution of some species is closely allied with depth and sediment type or both. No attempt was made to quantify species association. Title: Marine resource surveys on the continental shelf off Oregon, 1971-74 : completion report July 1, 1971 to June 30, 1975 Author: Forsberg, Brent O., United States. National Marine Fisheries Service, Ten Eyck, Neil, Demory, Robert L., Hosie, Michael J. Groundfish surveys off Oregon were conducted over a four year period (1971-74) between the Columbia River and Cape Blanco. Primary purpose of the surveys was to obtain estimates of biomass of important groundfish occupying the continental shelf and upper continental slope. Survey design was based on a 5 x 5 N mi grid with a random starting point. This resulted in trawling intensity of about 1 tow per 25 N mi² of trawlable bottom. Samples for age, size and sex composition were taken from important species of flatfish. Weights of all species caught were obtained. Estimates of biomass (a11 species) were 283,750 metric tons in 1971-72 and 235,117 metric tons in 1973-74. Pacific hake was the most abundant species followed by Dover sole. Estimates of potential yield were determined for five species of flatfish. Data indicate that only petrale sole are being fully exploited. Increased yield could be obtained without increasing fishing effort if economic conditions were such that the species caught were more completely utilized. Distribution of major species is depicted by catch maps. Distribution of some species is closely allied with depth and sediment type or both. No attempt was made to quantify species association. Close

• 245. [Article] The role of acoustical signals in the communicative behavior of the water scavenger beetles, Tropisternus (Coleoptera:hydrophilidae)

  The communicative behavior of five species and subspecies of Tropisternus Solier (Coleoptera: Hydrophilidae) was studied. These aquatic beetles have stress and calling chirps (both sexes), a second male ...

  Citation × Citation Citation Abstract Copy Title: The role of acoustical signals in the communicative behavior of the water scavenger beetles, Tropisternus (Coleoptera:hydrophilidae) Author: Ryker, Lee Chester The communicative behavior of five species and subspecies of Tropisternus Solier (Coleoptera: Hydrophilidae) was studied. These aquatic beetles have stress and calling chirps (both sexes), a second male calling signal (one species), a single male courtship sound (usually), a male copulatory sound, and a female aggressive rejection buzz (three species). Males utilize visual, not acoustical, clues to orient towards females at close range. Males court females with stereotyped movements, sounds, and tactile signals while positioned dorsally on the female. The role of chemical signals in recognition of sexual readiness, sex, or species remains unclear. A mark-release field study of T. ellipticus ruled out aggregation and territorial behavior as possible functions of acoustic signals. This species, at least, wanders freely and has no home range. Acoustic courtship signals were stereotyped, i.e., the same signal was always produced by males in particular positions of courtship, in T. natator and T. columbianus, but variable in T. ellipticus and two subspecies of T. lateralis. Experiments using models of beetles indicated that visual stimuli can release a calling chirp response and an approach in both sexes, or a courtship sound and an approach in males. Results of experiments utilizing broadcasts of tape recorded signals established that Tropisternus can hear water-borne acoustic signals even though auditory receptors are as yet unknown in Coleoptera. Males of T. natator and T. lateralis nimbatus discriminated female calling chirps from other acoustic signals. Female calling chirps stimulated males to emit calling chirps, to cease feeding and begin swimming, and to approach models of beetles (searching behavior). Males of T. ellipticus and T. lateralis limbalis, species from populations in western Oregon, did not respond predictably to acoustic signals. T. natator and T. lateralis nimbatus, which responded to calling chirps, are from populations in southern Michigan, where four species of Tropisternus share breeding sites. In contrast, the three species in western Oregon probably breed in different microhabitats. The lack of mating interference between species in western Oregon may have allowed the loosening of stereotypy in courtship seen in T. ellipticus and the degeneration of the calling function of acoustic signals seen in T. ellipticus and T. lateralis limbalis. Title: The role of acoustical signals in the communicative behavior of the water scavenger beetles, Tropisternus (Coleoptera:hydrophilidae) Author: Ryker, Lee Chester The communicative behavior of five species and subspecies of Tropisternus Solier (Coleoptera: Hydrophilidae) was studied. These aquatic beetles have stress and calling chirps (both sexes), a second male calling signal (one species), a single male courtship sound (usually), a male copulatory sound, and a female aggressive rejection buzz (three species). Males utilize visual, not acoustical, clues to orient towards females at close range. Males court females with stereotyped movements, sounds, and tactile signals while positioned dorsally on the female. The role of chemical signals in recognition of sexual readiness, sex, or species remains unclear. A mark-release field study of T. ellipticus ruled out aggregation and territorial behavior as possible functions of acoustic signals. This species, at least, wanders freely and has no home range. Acoustic courtship signals were stereotyped, i.e., the same signal was always produced by males in particular positions of courtship, in T. natator and T. columbianus, but variable in T. ellipticus and two subspecies of T. lateralis. Experiments using models of beetles indicated that visual stimuli can release a calling chirp response and an approach in both sexes, or a courtship sound and an approach in males. Results of experiments utilizing broadcasts of tape recorded signals established that Tropisternus can hear water-borne acoustic signals even though auditory receptors are as yet unknown in Coleoptera. Males of T. natator and T. lateralis nimbatus discriminated female calling chirps from other acoustic signals. Female calling chirps stimulated males to emit calling chirps, to cease feeding and begin swimming, and to approach models of beetles (searching behavior). Males of T. ellipticus and T. lateralis limbalis, species from populations in western Oregon, did not respond predictably to acoustic signals. T. natator and T. lateralis nimbatus, which responded to calling chirps, are from populations in southern Michigan, where four species of Tropisternus share breeding sites. In contrast, the three species in western Oregon probably breed in different microhabitats. The lack of mating interference between species in western Oregon may have allowed the loosening of stereotypy in courtship seen in T. ellipticus and the degeneration of the calling function of acoustic signals seen in T. ellipticus and T. lateralis limbalis. Close

• 246. [Article] Identification and systematics of larvae of Artedius, Clinocottus, and Oligocottus (Scorpaeniformes:Cottidae)

  Complete, identified, developmental series of larval cottids Artedius fenestralis, A. creaseri, A. meanyi, Oligocottus snyderi, Clinocottus embryum, and C. globiceps are described for the first time. In ...

  Citation × Citation Citation Abstract Copy Title: Identification and systematics of larvae of Artedius, Clinocottus, and Oligocottus (Scorpaeniformes:Cottidae) Author: Washington, Betsy B. Complete, identified, developmental series of larval cottids Artedius fenestralis, A. creaseri, A. meanyi, Oligocottus snyderi, Clinocottus embryum, and C. globiceps are described for the first time. In addition, redescriptions of four species, Artedius harringtoni, A. lateralis, Oligocottus maculosus, and Clinocottus acuticeps are included that provide new and comparative information on larval development. Partial developmental series of two species, Artedius Type 3 and Clinocottus analis, are also described and illustrated for the first time. Using the methods of phylogenetic analysis proposed by Hennig (1966), characters of the larvae of 13 species of Artedius, Clinocottus, and Oligocottus are examined in terms of synapomorphic states. Number and pattern of preopercular spines, gut diverticula, body shape, and a bubble of skin at the nape are identified as synapomorphic characters useful in systematic analysis of this group. The synapomorphic character, multiple preopercular spines, provides strong evidence that Clinocottus acuticeps, C. analis, C. embryum, C. globiceps, C. recalvus, Oligocottus maculosus, 0. snyderi, Artedius fenestralis, A. harringtoni, A. lateralis, and A. Type 3 form a monophyletic group within the Cottidae. Within this group, the species of Clinocottus and Oligocottus are very closely related; however, each genus appears to be monophyletic. Larvae of all species of Clinocottus possess the synapomorphy, auxiliary preopercular spines. Larval Oligocottus maculosus and 0. snyderi share two derived characters, dorsal gut bumps and a bubble of skin at the nape. Artedius fenestralis, A. harringtoni, A. lateralis, and A. Type also form a monophyletic group closely related to Clinocottus and Oligocottus on the basis of a unique multiple preopercular spine pattern. Synapomorphic characters of the larvae provide strong evidence that A. creaseri and A. meanyi are more closely related to Icelinus than to species of Clinocottus, Oligocottus maculosus, O. snyderi, Artedius fenestralis, A. harringtoni, A. lateralis, and A. Type 3. Characters of the larvae strongly indicate that the genus Artedius as defined by Bolin (1934, 1947) is not monophyletic and that A. creaseri and A. meanyi should be placed separately from the other species of Artedius. Clarification of the exact position of these two species in relation to Icelinus and the Artedius-Clinocottus-Oligocottus group must await identification of larvae of all species of Icelinus and reexamination of characters of adult Icelinus and Artedius. Title: Identification and systematics of larvae of Artedius, Clinocottus, and Oligocottus (Scorpaeniformes:Cottidae) Author: Washington, Betsy B. Complete, identified, developmental series of larval cottids Artedius fenestralis, A. creaseri, A. meanyi, Oligocottus snyderi, Clinocottus embryum, and C. globiceps are described for the first time. In addition, redescriptions of four species, Artedius harringtoni, A. lateralis, Oligocottus maculosus, and Clinocottus acuticeps are included that provide new and comparative information on larval development. Partial developmental series of two species, Artedius Type 3 and Clinocottus analis, are also described and illustrated for the first time. Using the methods of phylogenetic analysis proposed by Hennig (1966), characters of the larvae of 13 species of Artedius, Clinocottus, and Oligocottus are examined in terms of synapomorphic states. Number and pattern of preopercular spines, gut diverticula, body shape, and a bubble of skin at the nape are identified as synapomorphic characters useful in systematic analysis of this group. The synapomorphic character, multiple preopercular spines, provides strong evidence that Clinocottus acuticeps, C. analis, C. embryum, C. globiceps, C. recalvus, Oligocottus maculosus, 0. snyderi, Artedius fenestralis, A. harringtoni, A. lateralis, and A. Type 3 form a monophyletic group within the Cottidae. Within this group, the species of Clinocottus and Oligocottus are very closely related; however, each genus appears to be monophyletic. Larvae of all species of Clinocottus possess the synapomorphy, auxiliary preopercular spines. Larval Oligocottus maculosus and 0. snyderi share two derived characters, dorsal gut bumps and a bubble of skin at the nape. Artedius fenestralis, A. harringtoni, A. lateralis, and A. Type also form a monophyletic group closely related to Clinocottus and Oligocottus on the basis of a unique multiple preopercular spine pattern. Synapomorphic characters of the larvae provide strong evidence that A. creaseri and A. meanyi are more closely related to Icelinus than to species of Clinocottus, Oligocottus maculosus, O. snyderi, Artedius fenestralis, A. harringtoni, A. lateralis, and A. Type 3. Characters of the larvae strongly indicate that the genus Artedius as defined by Bolin (1934, 1947) is not monophyletic and that A. creaseri and A. meanyi should be placed separately from the other species of Artedius. Clarification of the exact position of these two species in relation to Icelinus and the Artedius-Clinocottus-Oligocottus group must await identification of larvae of all species of Icelinus and reexamination of characters of adult Icelinus and Artedius. Close

• 247. [Article] A taxonomic and ecologic comparison of the floras of Iron and Fairview Mountains in Oregon

  Many topographic units in the state of Oregon have been only partially explored botanically and very few areas have been collected intensively. Two such areas were selected and a detailed investigation ...

  Citation × Citation Citation Abstract Copy Title: A taxonomic and ecologic comparison of the floras of Iron and Fairview Mountains in Oregon Author: Baker, William Hudson, 1911- Many topographic units in the state of Oregon have been only partially explored botanically and very few areas have been collected intensively. Two such areas were selected and a detailed investigation was made of the vegetation. Fairview Mountain and Iron Mountain are strategically located geographically and climatically. The former in a region where certain southern species find their northern limit and several species their southern limit. The latter is situated in an area high in endemic species and long considered the last out-post in Oregon of a predominantly Californian flora. Three of the Merriam life zones are recognized on Fairview Mountain, the Hudsonian, Canadian, and Transition. Only two life zones are acknowledged on Iron Mountain, the Canadian and Transition. The flora of Fairview Mountain consists of species representing three different floral provinces. These can be divided into the Northern element, Southern element, and Eastern element. The Northern element is predominant, equaling 14%; while the Southern and Eastern element each equal 8%. The class of plants which have a continuous range in three directions, equals 70% of the species. The plants of Iron Mountain are made up mostly of species coming from two different floral provinces, the Northern element and the Southern element. Another small segment of the population consists of the endemic species. The Eastern element comprises only 2%. By far the largest group of plants represents the Southern element with 20% of the total flora. The Northern element equals 3%. The plants which have a continuous range in 3 directions equal 72%. The plants adventive to Fairview Mountain equal 5%, which is below the average for the state of Oregon. The introduced plants of Iron Mountain consist of 10% of the total flora, which is equal to the state average. The Biological Spectrum was determined for both mountains according to the Raunkiaer Method. These spectra were in turn compared with each other, and with other regions in the north-west to obtain a statistical measurement of climate based on the plant life. The climate of both mountains is predominantly cryptophytic and hemi-cryptophytic. It was found in making a comparison of Iron Mountain and Fairview Mountain that the former had a reduction of 7% in hemicryptophytes and cryptophytes; a 3% increase in phanerophytes and a 1% increase in therophytes. This indicates the influence of a modified coastal climate due to proximity of the ocean. For a number of species in the flora of both mountains, the present study revealed extensions in range. These species, for the most part, have entered the region from typically different floral provinces. New distributional records for Fairview Mountain total 15%. New distributional records for Iron Mountain total 14%. The flora of Fairview Mountain includes 315 species of plants of which 95% appear to be indigenous. The flora of Iron Mountain consists of 300 species and varieties of plants, 90% of which are native. The annotated catalogues of the plants of both mountains indicate that the two mountains exhibit a significantly diverse flora within the comparatively narrow limits of the areas to which this investigation was confined. The flora of each mountain represented 10% of the total flora of the state and from 43 to 50% of the families listed for the state were represented. Polygonum cascadense was described as new from Fairview Mountain. It belongs to the subgenus Avicularia of the family Polygonaceae. The study was based on extensive field collections made over a period of years by the author; and upon published data, the latter consisting largely of general or casual comments of little definitive value. Keys to the families, genera and species were prepared and the plants are listed in the catalogue with notes on abundance, range, and habitat of the various species. The zonal distribution and life form of each plant is also given. Title: A taxonomic and ecologic comparison of the floras of Iron and Fairview Mountains in Oregon Author: Baker, William Hudson, 1911- Many topographic units in the state of Oregon have been only partially explored botanically and very few areas have been collected intensively. Two such areas were selected and a detailed investigation was made of the vegetation. Fairview Mountain and Iron Mountain are strategically located geographically and climatically. The former in a region where certain southern species find their northern limit and several species their southern limit. The latter is situated in an area high in endemic species and long considered the last out-post in Oregon of a predominantly Californian flora. Three of the Merriam life zones are recognized on Fairview Mountain, the Hudsonian, Canadian, and Transition. Only two life zones are acknowledged on Iron Mountain, the Canadian and Transition. The flora of Fairview Mountain consists of species representing three different floral provinces. These can be divided into the Northern element, Southern element, and Eastern element. The Northern element is predominant, equaling 14%; while the Southern and Eastern element each equal 8%. The class of plants which have a continuous range in three directions, equals 70% of the species. The plants of Iron Mountain are made up mostly of species coming from two different floral provinces, the Northern element and the Southern element. Another small segment of the population consists of the endemic species. The Eastern element comprises only 2%. By far the largest group of plants represents the Southern element with 20% of the total flora. The Northern element equals 3%. The plants which have a continuous range in 3 directions equal 72%. The plants adventive to Fairview Mountain equal 5%, which is below the average for the state of Oregon. The introduced plants of Iron Mountain consist of 10% of the total flora, which is equal to the state average. The Biological Spectrum was determined for both mountains according to the Raunkiaer Method. These spectra were in turn compared with each other, and with other regions in the north-west to obtain a statistical measurement of climate based on the plant life. The climate of both mountains is predominantly cryptophytic and hemi-cryptophytic. It was found in making a comparison of Iron Mountain and Fairview Mountain that the former had a reduction of 7% in hemicryptophytes and cryptophytes; a 3% increase in phanerophytes and a 1% increase in therophytes. This indicates the influence of a modified coastal climate due to proximity of the ocean. For a number of species in the flora of both mountains, the present study revealed extensions in range. These species, for the most part, have entered the region from typically different floral provinces. New distributional records for Fairview Mountain total 15%. New distributional records for Iron Mountain total 14%. The flora of Fairview Mountain includes 315 species of plants of which 95% appear to be indigenous. The flora of Iron Mountain consists of 300 species and varieties of plants, 90% of which are native. The annotated catalogues of the plants of both mountains indicate that the two mountains exhibit a significantly diverse flora within the comparatively narrow limits of the areas to which this investigation was confined. The flora of each mountain represented 10% of the total flora of the state and from 43 to 50% of the families listed for the state were represented. Polygonum cascadense was described as new from Fairview Mountain. It belongs to the subgenus Avicularia of the family Polygonaceae. The study was based on extensive field collections made over a period of years by the author; and upon published data, the latter consisting largely of general or casual comments of little definitive value. Keys to the families, genera and species were prepared and the plants are listed in the catalogue with notes on abundance, range, and habitat of the various species. The zonal distribution and life form of each plant is also given. Close

• 248. [Article] Habitat associations and life histories of odonata in riverine wetlands of the Willamette Valley, Oregon

  This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions ...

  Citation × Citation Citation Abstract Copy Title: Habitat associations and life histories of odonata in riverine wetlands of the Willamette Valley, Oregon Author: Beatty, Christopher D. This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions were characterized over two seasons in the autumn of 2000 and the spring of 2001-at twenty-seven wetlands located throughout the valley. Distributions of nymphs and adults were compared with wetland habitat conditions that may affect odonate diversity. Odonate nymph and adult distributions were analyzed through Hierarchical Agglomerative cluster analysis (HA). HA identified discrete clusters of sites based on the distributions of species in the genera Aeshna, Erythemis, Lestes, Libellula, Pachydiplax, Sympetrum and Tramea. To identify habitat associations with odonate species, nymph and adult data were analyzed by Non-metric Multidimensional Scaling (NMS). NMS revealed that odonate distributions are associated with site hydrology, water depth and temperature, the presence of large emergent plants (e.g. Typha latifolia), the presence of fish, and surrounding landcover. These data will provide guidance for wetland managers in the use of odonates as indicators of wetland health. To further examine the relationship between odonate species and their wetland habitats, quantitative life history data for the 27 odonate species were analyzed to determine functional associations between species attributes and the environments in which they are found. Oviposition location, presence of a resting egg, over-wintering life stage, nymphal foraging strategy and adult flight season were subjected to NMS, to determine biological similarities between species occupying particular locations. Life history patterns correlated strongly with hydrology. Analysis of sites by odonate species ricimess found a relationship between richness and site hydrology, but failed to explain the distribution of several species associated with wetlands that dry during part of the year. We conclude from our results that species-level life history data are essential for explaining odonate distributions. We determined that the presence of odonate species in a wetland is indicative of habitat condition, that analysis of odonate distributions at the species level is necessary to understand habitat associations, and that analysis of life-history attributes provides a functional understanding of odonate distributions that measurements of species richness or the distributions of generaor families alone cannot explain. Title: Habitat associations and life histories of odonata in riverine wetlands of the Willamette Valley, Oregon Author: Beatty, Christopher D. This thesis explored the distributions and life histories of dragonflies and damselflies (Insecta: Odonata) of the riverine wetlands of the Willamette Valley in western Oregon, USA. Odonate species distributions were characterized over two seasons in the autumn of 2000 and the spring of 2001-at twenty-seven wetlands located throughout the valley. Distributions of nymphs and adults were compared with wetland habitat conditions that may affect odonate diversity. Odonate nymph and adult distributions were analyzed through Hierarchical Agglomerative cluster analysis (HA). HA identified discrete clusters of sites based on the distributions of species in the genera Aeshna, Erythemis, Lestes, Libellula, Pachydiplax, Sympetrum and Tramea. To identify habitat associations with odonate species, nymph and adult data were analyzed by Non-metric Multidimensional Scaling (NMS). NMS revealed that odonate distributions are associated with site hydrology, water depth and temperature, the presence of large emergent plants (e.g. Typha latifolia), the presence of fish, and surrounding landcover. These data will provide guidance for wetland managers in the use of odonates as indicators of wetland health. To further examine the relationship between odonate species and their wetland habitats, quantitative life history data for the 27 odonate species were analyzed to determine functional associations between species attributes and the environments in which they are found. Oviposition location, presence of a resting egg, over-wintering life stage, nymphal foraging strategy and adult flight season were subjected to NMS, to determine biological similarities between species occupying particular locations. Life history patterns correlated strongly with hydrology. Analysis of sites by odonate species ricimess found a relationship between richness and site hydrology, but failed to explain the distribution of several species associated with wetlands that dry during part of the year. We conclude from our results that species-level life history data are essential for explaining odonate distributions. We determined that the presence of odonate species in a wetland is indicative of habitat condition, that analysis of odonate distributions at the species level is necessary to understand habitat associations, and that analysis of life-history attributes provides a functional understanding of odonate distributions that measurements of species richness or the distributions of generaor families alone cannot explain. Close

• 249. [Article] An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli

  Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, ...

  Citation × Citation Citation Abstract Copy Title: An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli Author: Granek, Elise F. Year: 2000 Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, as part of a project to assess areas for nature reserves which will be able to protect and conserve forest resources in the islands; the bat is postulated to be a useful indicator of undisturbed forest. Known roost sites (n=9) before the survey were between 500 and 1100 m altitude, on steeply sloping land, with some indigenous forest cover present. Thirteen new potential roost sites were identified, of which at least six were confirmed as roost sites for P. livingstonii. Bats showed positive associations with two tree species: Gambeya sp. and Nuxia pseudodentata. The study also investigated the participation by local village communities in monitoring bat populations, and the protection of roost sites. Title: An analysis of Pteropus livingstonii roost habitat: Indicators for forest conservation on Anjouan and Moheli Author: Granek, Elise F. Year: 2000 Livingstone's fruit bat (Pteropus livingstonii) is an endangered and endemic species found only on the islands of Anjouan and Mohéli, Comoros. A study was conducted into the habitats selected by P. livingstonii, as part of a project to assess areas for nature reserves which will be able to protect and conserve forest resources in the islands; the bat is postulated to be a useful indicator of undisturbed forest. Known roost sites (n=9) before the survey were between 500 and 1100 m altitude, on steeply sloping land, with some indigenous forest cover present. Thirteen new potential roost sites were identified, of which at least six were confirmed as roost sites for P. livingstonii. Bats showed positive associations with two tree species: Gambeya sp. and Nuxia pseudodentata. The study also investigated the participation by local village communities in monitoring bat populations, and the protection of roost sites. Close

• 250. [Article] Crown structure, stand dynamics, and production ecology of two species mixtures in the central Oregon Cascades

  Knowledge of stand structure, stand dynamics, and production ecology of species mixtures lags well behind that of single-species, even-aged stands. Two mixed-species spacing trials in central Oregon allowed ...

  Citation × Citation Citation Abstract Copy Title: Crown structure, stand dynamics, and production ecology of two species mixtures in the central Oregon Cascades Author: Garber, Sean M. Knowledge of stand structure, stand dynamics, and production ecology of species mixtures lags well behind that of single-species, even-aged stands. Two mixed-species spacing trials in central Oregon allowed investigation of mixed-species dynamics in a controlled experimental setting. The first site, Pringle Butte, is a mixture of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and lodgepole pine (Pinus contorta Dougl. ex Loud.). The second site, Lookout Mountain, is a mixture of ponderosa pine and grand fir (Abies grandis (Dougl. ex D. Don) Lindl.). Both studies were planted in the early 1970's and established as replacement series under a split-plot design with spacing as the whole plot factor and species composition as the split-plot factor. Plot data have been collected since 1975. In the summer of 2001, 95 trees outside the plots were destructively sampled and 114 plots were intensively sampled. From these data the following were developed and assessed: (i) volume growth dynamics; (ii) models predicting individual tree vertical foliage distributions; (iii) models describing the profile of maximum branch diameter within a tree; and (iv) volume growth efficiency. In both studies, the least shade tolerant species had the fastest early growth rates. Over time, volume development depended on both spacing and composition; P. ponderosa was able to catch up with P. contorta within the mixtures and between the pure plots at Pringle Butte, whereas A. grandis still lags behind P. ponderosa, although its relative contribution increases with increasing spacing at Lookout Mountain. Relative yields of mixtures were greater than one, but significantly so only in the A. grandis - P. ponderosa mixtures. Branch leaf area equations indicate that, given branch diameter, position in the crown is an important factor in estimating leaf area. Tree leaf area was best predicted by the product of tree basal area and the ratio of crown length above breast height, a surrogate for sapwood area at crown base. Branch- and tree-level predictions differed significantly between sites for P. ponderosa. Relative vertical foliage distribution on individual trees of both A. grandis and P. ponderosa shifted up with an decrease in relative height, while increased spacing resulted in a downward shift in relative foliage distribution on P. ponderosa at Lookout Mountain. Spacing and competing species also affected absolute foliage distributions in a manner consistent with expected influence on crown length. For all species and spacings, profiles of maximum branch diameter were curvilinear, decreasing near the crown base. Tree variables such as diameter, height, and crown length were able to account for spacing. The effect of species composition on branch profiles was more difficult to assess. Profiles of maximum branch diameter increase with increasing spacing and tree relative height, but the effects of species composition depended on spacing in all species. More pronounced increases in maximum branch diameter profiles with increasing relative height within the crown were found in the subordinate species in mixtures than in adjacent pure plots and in its overtopping competitor. In contrast, the overtopping species had a larger spacing response in the pure plots than in mixed plots. The ratio of leaf biomass to crown biomass decreased with increasing spacing, but was also influenced by species composition. Growth efficiency decreased with increasing spacing, except in Abies grandis, which peaked at the intermediate spacing. Results suggest that plot growth efficiency peaks at intermediate densities depending on composition. At wider spacings, growth efficiency appears to be limited by greater allocation of carbon to branches for both construction and maintenance respiration. At tighter spacings, growth efficiency appears to be limited by competition among individuals, reducing resources per individual and promoting differentiation. In dense, differentiated stands, the poorest individuals contribute leaf area but little growth, reducing stand growth efficiency. Spacing and species composition play an important role in stand development and resulting crown structure. Mixtures can produce a more diverse array of stand structures and yield similar if not more volume than pure stands of the higher yielding species. Management of mixed-species stands must take into account the interactions between spacing and species' growth dynamics, but this same interaction opens possibilities for a wide variety of stand structures for a given species composition. Title: Crown structure, stand dynamics, and production ecology of two species mixtures in the central Oregon Cascades Author: Garber, Sean M. Knowledge of stand structure, stand dynamics, and production ecology of species mixtures lags well behind that of single-species, even-aged stands. Two mixed-species spacing trials in central Oregon allowed investigation of mixed-species dynamics in a controlled experimental setting. The first site, Pringle Butte, is a mixture of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and lodgepole pine (Pinus contorta Dougl. ex Loud.). The second site, Lookout Mountain, is a mixture of ponderosa pine and grand fir (Abies grandis (Dougl. ex D. Don) Lindl.). Both studies were planted in the early 1970's and established as replacement series under a split-plot design with spacing as the whole plot factor and species composition as the split-plot factor. Plot data have been collected since 1975. In the summer of 2001, 95 trees outside the plots were destructively sampled and 114 plots were intensively sampled. From these data the following were developed and assessed: (i) volume growth dynamics; (ii) models predicting individual tree vertical foliage distributions; (iii) models describing the profile of maximum branch diameter within a tree; and (iv) volume growth efficiency. In both studies, the least shade tolerant species had the fastest early growth rates. Over time, volume development depended on both spacing and composition; P. ponderosa was able to catch up with P. contorta within the mixtures and between the pure plots at Pringle Butte, whereas A. grandis still lags behind P. ponderosa, although its relative contribution increases with increasing spacing at Lookout Mountain. Relative yields of mixtures were greater than one, but significantly so only in the A. grandis - P. ponderosa mixtures. Branch leaf area equations indicate that, given branch diameter, position in the crown is an important factor in estimating leaf area. Tree leaf area was best predicted by the product of tree basal area and the ratio of crown length above breast height, a surrogate for sapwood area at crown base. Branch- and tree-level predictions differed significantly between sites for P. ponderosa. Relative vertical foliage distribution on individual trees of both A. grandis and P. ponderosa shifted up with an decrease in relative height, while increased spacing resulted in a downward shift in relative foliage distribution on P. ponderosa at Lookout Mountain. Spacing and competing species also affected absolute foliage distributions in a manner consistent with expected influence on crown length. For all species and spacings, profiles of maximum branch diameter were curvilinear, decreasing near the crown base. Tree variables such as diameter, height, and crown length were able to account for spacing. The effect of species composition on branch profiles was more difficult to assess. Profiles of maximum branch diameter increase with increasing spacing and tree relative height, but the effects of species composition depended on spacing in all species. More pronounced increases in maximum branch diameter profiles with increasing relative height within the crown were found in the subordinate species in mixtures than in adjacent pure plots and in its overtopping competitor. In contrast, the overtopping species had a larger spacing response in the pure plots than in mixed plots. The ratio of leaf biomass to crown biomass decreased with increasing spacing, but was also influenced by species composition. Growth efficiency decreased with increasing spacing, except in Abies grandis, which peaked at the intermediate spacing. Results suggest that plot growth efficiency peaks at intermediate densities depending on composition. At wider spacings, growth efficiency appears to be limited by greater allocation of carbon to branches for both construction and maintenance respiration. At tighter spacings, growth efficiency appears to be limited by competition among individuals, reducing resources per individual and promoting differentiation. In dense, differentiated stands, the poorest individuals contribute leaf area but little growth, reducing stand growth efficiency. Spacing and species composition play an important role in stand development and resulting crown structure. Mixtures can produce a more diverse array of stand structures and yield similar if not more volume than pure stands of the higher yielding species. Management of mixed-species stands must take into account the interactions between spacing and species' growth dynamics, but this same interaction opens possibilities for a wide variety of stand structures for a given species composition. Close