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• 21. [Article] Salmon anchor habitats in Tillamook and Clatsop State Forests, Oregon : science, policy, economics ; an annotated bibliography.

  This annotated bibliography was prepared for the Salmon Anchor Habitat Work Group. This group was formed by the Oregon Department of Forestry to review and evaluate the Salmon Anchor Habitat Strategy as ...

  Citation × Citation Citation Abstract Copy Title: Salmon anchor habitats in Tillamook and Clatsop State Forests, Oregon : science, policy, economics ; an annotated bibliography. Author: Institute for Natural Resources, Behan, Jeff This annotated bibliography was prepared for the Salmon Anchor Habitat Work Group. This group was formed by the Oregon Department of Forestry to review and evaluate the Salmon Anchor Habitat Strategy as directed by the 2003 Oregon Legislature. The Salmon Anchor Habitat Strategy is a component of management plans developed by the Oregon Department of Forestry, for the Tillamook and Clatsop State Forests in northwestern Oregon. The references in this bibliography are grouped according to the categories of questions raised by the Salmon Anchor Habitat Work Group. Title: Salmon anchor habitats in Tillamook and Clatsop State Forests, Oregon : science, policy, economics ; an annotated bibliography. Author: Institute for Natural Resources, Behan, Jeff This annotated bibliography was prepared for the Salmon Anchor Habitat Work Group. This group was formed by the Oregon Department of Forestry to review and evaluate the Salmon Anchor Habitat Strategy as directed by the 2003 Oregon Legislature. The Salmon Anchor Habitat Strategy is a component of management plans developed by the Oregon Department of Forestry, for the Tillamook and Clatsop State Forests in northwestern Oregon. The references in this bibliography are grouped according to the categories of questions raised by the Salmon Anchor Habitat Work Group. Close

• 22. [Article] Physiological and anatomical studies of several groups of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) seedlings which demonstrated differential survival potential under drought stress

  Several hundred two year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in an enclosure designed to permit control of soil moisture. The seedlings came from five seed sources ...

  Citation × Citation Citation Abstract Copy Title: Physiological and anatomical studies of several groups of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) seedlings which demonstrated differential survival potential under drought stress Author: Heiner, Terry Charles, 1941- Several hundred two year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in an enclosure designed to permit control of soil moisture. The seedlings came from five seed sources in southern Oregon and one seed source in northwestern Oregon. Mortality terminal and lateral budburst, and soil moisture were recorded during the growing season. The final death count showed that the mortality of the northwest Oregon seed source (84%) differed significantly (at the 1% level) from that of four southern Oregon seed sources (ca 44%) and that the mortality of all differed significantly from that of a fifth southern Oregon source (30%). The purpose of this study was to determine what anatomical, morphological, and physiological characteristics were associated with survival. Root length, calcium-potassium ratio, cuticle thickness, shoot-root ratio, and root surface area are not correlated with mortality. A relation between mortality and the amount and rate of budburst was found. The low bud activity and high mortality of the northwest Oregon seedlings may be an expression of their physiological condition. Earlier bud activity by the southern Oregon seedlings may be a response to a lower minimum temperature, and is a survival advantage in areas with severe summer drought. Title: Physiological and anatomical studies of several groups of Douglas-fir (pseudotsuga menziesii (Mirb.) Franco) seedlings which demonstrated differential survival potential under drought stress Author: Heiner, Terry Charles, 1941- Several hundred two year old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were planted in an enclosure designed to permit control of soil moisture. The seedlings came from five seed sources in southern Oregon and one seed source in northwestern Oregon. Mortality terminal and lateral budburst, and soil moisture were recorded during the growing season. The final death count showed that the mortality of the northwest Oregon seed source (84%) differed significantly (at the 1% level) from that of four southern Oregon seed sources (ca 44%) and that the mortality of all differed significantly from that of a fifth southern Oregon source (30%). The purpose of this study was to determine what anatomical, morphological, and physiological characteristics were associated with survival. Root length, calcium-potassium ratio, cuticle thickness, shoot-root ratio, and root surface area are not correlated with mortality. A relation between mortality and the amount and rate of budburst was found. The low bud activity and high mortality of the northwest Oregon seedlings may be an expression of their physiological condition. Earlier bud activity by the southern Oregon seedlings may be a response to a lower minimum temperature, and is a survival advantage in areas with severe summer drought. Close

• 23. [Article] Consumptive use of surface water by Willamette Basin municipalities

  The consumptive water use of six cities in the Willamette Basin of northwestern Oregon was evaluated for the period 1960-66. Consumptive use ratios were obtained by analyzing data from monthly water supply ...

  Citation × Citation Citation Abstract Copy Title: Consumptive use of surface water by Willamette Basin municipalities Author: Mittelstadt, Richard Lee The consumptive water use of six cities in the Willamette Basin of northwestern Oregon was evaluated for the period 1960-66. Consumptive use ratios were obtained by analyzing data from monthly water supply and sewage flow records. The average annual consumptive use for the six cities was found to be 26 percent, and the average monthly ratios varied from essentially zero in the winter months to as high as 53 percent in July and August. The principal factors affecting consumptive use were found to be weather conditions, lawn watering, water system losses, cost of water, air conditioning, and proportion of water used for industrial purposes. While not affecting consumptive use, per se, sewer infiltration, storm runoff, and incomplete water or sewer systems can affect the calculated consumptive use ratios. The extent to which a water right is consumptive is inferred by the use to which the water is put. On the basis of existing water law and past court decisions, it is concluded that a city has the legal right to consume the full amount of its municipal water right providing the water is used strictly in accordance with the conditions of its permit. Title: Consumptive use of surface water by Willamette Basin municipalities Author: Mittelstadt, Richard Lee The consumptive water use of six cities in the Willamette Basin of northwestern Oregon was evaluated for the period 1960-66. Consumptive use ratios were obtained by analyzing data from monthly water supply and sewage flow records. The average annual consumptive use for the six cities was found to be 26 percent, and the average monthly ratios varied from essentially zero in the winter months to as high as 53 percent in July and August. The principal factors affecting consumptive use were found to be weather conditions, lawn watering, water system losses, cost of water, air conditioning, and proportion of water used for industrial purposes. While not affecting consumptive use, per se, sewer infiltration, storm runoff, and incomplete water or sewer systems can affect the calculated consumptive use ratios. The extent to which a water right is consumptive is inferred by the use to which the water is put. On the basis of existing water law and past court decisions, it is concluded that a city has the legal right to consume the full amount of its municipal water right providing the water is used strictly in accordance with the conditions of its permit. Close

• 24. [Article] Texture analysis riparian coniferous forest ADAR imagery to identify potential ecological indicators for monitoring

  The Airborne Data Acquisition and Registration (ADAR) remote sensing system captured one-meter resolution imagery of 25 different riparian sites in drift Creek Basin of coastal northwestern Oregon, USA. ...

  Citation × Citation Citation Abstract Copy Title: Texture analysis riparian coniferous forest ADAR imagery to identify potential ecological indicators for monitoring Author: Fiorella, M., Barker, Jerry R., Ringold, P.L., Bradshaw, Gay, Bollman, Mike The Airborne Data Acquisition and Registration (ADAR) remote sensing system captured one-meter resolution imagery of 25 different riparian sites in drift Creek Basin of coastal northwestern Oregon, USA. The multispectral, digital data characterized riparian areas with the intent to develop ecological indicators for long-term monitoring. Title: Texture analysis riparian coniferous forest ADAR imagery to identify potential ecological indicators for monitoring Author: Fiorella, M., Barker, Jerry R., Ringold, P.L., Bradshaw, Gay, Bollman, Mike The Airborne Data Acquisition and Registration (ADAR) remote sensing system captured one-meter resolution imagery of 25 different riparian sites in drift Creek Basin of coastal northwestern Oregon, USA. The multispectral, digital data characterized riparian areas with the intent to develop ecological indicators for long-term monitoring. Close

• 25. [Article] Post-breeding habitat selection by songbirds in the headwaters of the Trask River, northwestern Oregon

  Little is known on the importance of riparian areas to birds near small headwater streams in mesic forests. Progress towards understanding limiting factors that affect bird populations has been difficult ...

  Citation × Citation Citation Abstract Copy Title: Post-breeding habitat selection by songbirds in the headwaters of the Trask River, northwestern Oregon Author: Jenkins, Stephanie R. Little is known on the importance of riparian areas to birds near small headwater streams in mesic forests. Progress towards understanding limiting factors that affect bird populations has been difficult because of lack of information beyond the breeding period. I compared bird assemblages between headwater riparian and upland areas throughout the post-breeding period by capturing birds using mist-nets in six paired riparian and upland locations along six headwater streams of the Trask River in northwestern Oregon. In order to assess whether birds prefer headwater riparian areas, I also examined factors affecting habitat selection by juvenile Swainson's thrushes (n=37) using radio telemetry. While riparian and upland locations had similar coarse wood volume and fruiting and tall (> 1.3 m tall) shrub cover, riparian locations had less shrub cover (< 1.3 m tall) and different shrub composition than upland locations. Total capture rate was double that of upland in riparian locations, while bird species richness was similar. Similar numbers of birds were captured in mist-nets oriented perpendicular and parallel to the stream suggesting that birds were not using riparian areas as movement corridors. Adult capture rate was greater in riparian locations than adjacent uplands while results of juvenile capture rates were ambiguous. Riparian locations supported higher capture rates of Swainson's thrushes and winter wrens than adjacent uplands. Higher arthropod abundance in riparian locations may best explain higher capture rates in riparian locations. Radio-tagged juvenile Swainson's thrushes were more likely to select habitat that was near streams with high proportions of deciduous mid-story cover 1.5 - 15 m in the vertical strata and large volumes of coarse wood; possibly due to cover from predation and sources of food (i.e., fruits and arthropods). I observed higher survival (97.3%) than reported in previous studies on independent juveniles which suggests that headwater streams contribute positively to the demography of the Swainson's thrush in the Pacific Northwest. In comparison with adjacent upland, headwater riparian areas appeared to be disproportionately used by songbirds during the post-breeding period even though vegetation differences were minimal. To assess if current policies sufficiently protect avian biodiversity, further research should evaluate how manipulation of vegetation affects bird distribution in headwater areas. Title: Post-breeding habitat selection by songbirds in the headwaters of the Trask River, northwestern Oregon Author: Jenkins, Stephanie R. Little is known on the importance of riparian areas to birds near small headwater streams in mesic forests. Progress towards understanding limiting factors that affect bird populations has been difficult because of lack of information beyond the breeding period. I compared bird assemblages between headwater riparian and upland areas throughout the post-breeding period by capturing birds using mist-nets in six paired riparian and upland locations along six headwater streams of the Trask River in northwestern Oregon. In order to assess whether birds prefer headwater riparian areas, I also examined factors affecting habitat selection by juvenile Swainson's thrushes (n=37) using radio telemetry. While riparian and upland locations had similar coarse wood volume and fruiting and tall (> 1.3 m tall) shrub cover, riparian locations had less shrub cover (< 1.3 m tall) and different shrub composition than upland locations. Total capture rate was double that of upland in riparian locations, while bird species richness was similar. Similar numbers of birds were captured in mist-nets oriented perpendicular and parallel to the stream suggesting that birds were not using riparian areas as movement corridors. Adult capture rate was greater in riparian locations than adjacent uplands while results of juvenile capture rates were ambiguous. Riparian locations supported higher capture rates of Swainson's thrushes and winter wrens than adjacent uplands. Higher arthropod abundance in riparian locations may best explain higher capture rates in riparian locations. Radio-tagged juvenile Swainson's thrushes were more likely to select habitat that was near streams with high proportions of deciduous mid-story cover 1.5 - 15 m in the vertical strata and large volumes of coarse wood; possibly due to cover from predation and sources of food (i.e., fruits and arthropods). I observed higher survival (97.3%) than reported in previous studies on independent juveniles which suggests that headwater streams contribute positively to the demography of the Swainson's thrush in the Pacific Northwest. In comparison with adjacent upland, headwater riparian areas appeared to be disproportionately used by songbirds during the post-breeding period even though vegetation differences were minimal. To assess if current policies sufficiently protect avian biodiversity, further research should evaluate how manipulation of vegetation affects bird distribution in headwater areas. Close

• 26. [Article] Geology, structure, and tectonic history of the Tualatin Basin, northwestern Oregon

  The northwest-trending Neogene Tualatin basin in northwestern Oregon is a pull-apart basin with approximately 750 m of post-middle Miocene structural relief. Gently tilted uplands capped by Columbia River ...

  Citation × Citation Citation Abstract Copy Title: Geology, structure, and tectonic history of the Tualatin Basin, northwestern Oregon Author: Popowski, Thomas Allan The northwest-trending Neogene Tualatin basin in northwestern Oregon is a pull-apart basin with approximately 750 m of post-middle Miocene structural relief. Gently tilted uplands capped by Columbia River Basalt Group surround the synclinal basin on all sides. Integrated gravity, aeromagnetic, and seismic reflection data indicated that the basin is underlain by 3 to 4 km of sub-horizontal, upper lower Eocene to middle Miocene age sedimentary and volcanic rocks. Up to 300 m of Columbia River Basalt overlie these older strata, in turn overlain by up to 400 m of late Miocene to Pleistocene, dominantly fluvio-lacustrine sediments. Late middle Eocene strong oblique convergence across the continental margin generated regional northeast-trending fissures in the forearc through which the Tillamook Volcanics and basalt of Waverly Heights erupted. Sinistral strike-slip faults, including the proto-Gales Creek-Mt. Angel structural zone, segmented the forearc into discrete blocks which rotated clockwise independently. A right-step in the Gales Creek-Mt. Angel system generated northeast-directed folding and faulting adjacent to the restraining bend, deforming rocks as young as upper Tillamook Volcanics. Regional uplift culminated in a late Eocene unconformity which removed the arkosic Spencer Formation northeast of the Gales Creek-Mt. Angel system, prior to subsidence of the forearc and burial by late Eocene and Oligocene tuffaceous sedimentary strata. The distribution of middle Miocene Columbia River Basalt Group flows shows no evidence of a structural or topographic Tualatin basin at that time. The syncline initiated along the present southwestern margin of the basin in late Miocene time, in response to uplift of the Coast Range and Portland Hills anticlines to the southwest and northeast, respectively. A late Pliocene decrease in convergence and consequent relative increase in the oblique component of convergence reactivated the Gales Creek-Mt. Angel structural zone as a dextral shear zone. The right-step acted as a releasing bend, allowing extension, increased subsidence and normal faulting along the basin margins, and volcanism within the basin. Subsequent development of transverse folds and reverse faults, northwest-trending riedel shears, northeast-trending antithetic faults, and basin-marginal normal faults, is consistent with classification of the Tualatin basin as a pull-apart basin in a dextral wrench system. Title: Geology, structure, and tectonic history of the Tualatin Basin, northwestern Oregon Author: Popowski, Thomas Allan The northwest-trending Neogene Tualatin basin in northwestern Oregon is a pull-apart basin with approximately 750 m of post-middle Miocene structural relief. Gently tilted uplands capped by Columbia River Basalt Group surround the synclinal basin on all sides. Integrated gravity, aeromagnetic, and seismic reflection data indicated that the basin is underlain by 3 to 4 km of sub-horizontal, upper lower Eocene to middle Miocene age sedimentary and volcanic rocks. Up to 300 m of Columbia River Basalt overlie these older strata, in turn overlain by up to 400 m of late Miocene to Pleistocene, dominantly fluvio-lacustrine sediments. Late middle Eocene strong oblique convergence across the continental margin generated regional northeast-trending fissures in the forearc through which the Tillamook Volcanics and basalt of Waverly Heights erupted. Sinistral strike-slip faults, including the proto-Gales Creek-Mt. Angel structural zone, segmented the forearc into discrete blocks which rotated clockwise independently. A right-step in the Gales Creek-Mt. Angel system generated northeast-directed folding and faulting adjacent to the restraining bend, deforming rocks as young as upper Tillamook Volcanics. Regional uplift culminated in a late Eocene unconformity which removed the arkosic Spencer Formation northeast of the Gales Creek-Mt. Angel system, prior to subsidence of the forearc and burial by late Eocene and Oligocene tuffaceous sedimentary strata. The distribution of middle Miocene Columbia River Basalt Group flows shows no evidence of a structural or topographic Tualatin basin at that time. The syncline initiated along the present southwestern margin of the basin in late Miocene time, in response to uplift of the Coast Range and Portland Hills anticlines to the southwest and northeast, respectively. A late Pliocene decrease in convergence and consequent relative increase in the oblique component of convergence reactivated the Gales Creek-Mt. Angel structural zone as a dextral shear zone. The right-step acted as a releasing bend, allowing extension, increased subsidence and normal faulting along the basin margins, and volcanism within the basin. Subsequent development of transverse folds and reverse faults, northwest-trending riedel shears, northeast-trending antithetic faults, and basin-marginal normal faults, is consistent with classification of the Tualatin basin as a pull-apart basin in a dextral wrench system. Close

• 27. [Article] Wildlife Health in Managed Forests : Immunity and Infectious Diseases in Wild Rodents of Oregon

  With continual and worldwide human population growth, our impact on the natural environment expands and intensifies every day. We consume natural resources, burn fossil fuels, and release toxic compounds ...

  Citation × Citation Citation Abstract Copy Title: Wildlife Health in Managed Forests : Immunity and Infectious Diseases in Wild Rodents of Oregon Author: Hanselmann, Rhea With continual and worldwide human population growth, our impact on the natural environment expands and intensifies every day. We consume natural resources, burn fossil fuels, and release toxic compounds into the air, water, and earth. We build roads that fragment the landscape, construct new settlements, and develop agricultural lands in previously undisturbed areas. And, we introduce non-native species, which compete with and/or prey on native ones. Our actions change the composition of ecosystems by effacing natural environments and decimating plant and animal populations. We have reached a time of unprecedented anthropogenic environmental change. And, while we recognize, and work feverishly to mitigate, countless consequences of our actions, we still lack a profound understanding of just as many of the corollaries of the environmental changes we provoke. One thing we do know is that human-induced changes in environmental conditions can affect health – from individual organisms, to plant and animal populations, all the way to the level of the ecosystem. Yet, the mechanisms underlying such adverse health outcomes are only partially understood. For instance, we know that alterations in the structure of plant and animal communities, the distribution and demographics of populations, and the abundance of individuals can influence the emergence or re-emergence of infectious diseases. Which species are present in a community, where, when, and in what numbers can all determine the dynamics of pathogens, lead to disease outbreaks, and provide opportunities for spillover into new species. However, given the many environmental-, population-, and organism-level factors involved, and the complexity by which these variables interact, detecting and predicting the ultimate consequences for the health of animal, including human, populations remains difficult. Wild animals play important roles in numerous infectious disease cycles, many of which are shared with humans. Considering this and the well-documented effects that human activity can have on wildlife populations, studying the impacts of anthropogenic environmental change on health in wildlife is highly relevant. To understand how human-induced environmental changes affect wildlife health and to make predictions about potential regional or even global consequences for the dynamics of infectious diseases, however, we first need to understand patterns at a local scale. Here, I describe variation in immune function in captive and wild rodent species native to managed forests in northwestern Oregon, and examine how intensive forest management practices affect these and other physiological processes, and the prevalence of infectious diseases, in a large-scale field experiment. In Chapter 2 of this dissertation, I present baseline data on simple immune parameters in an iconic inhabitant of old-growth forests in the Pacific Northwest, the red tree vole (Arborimus longicaudus). I show that both body condition and age are important for immune defenses in this species. Translating these findings to wild populations leads me to predict that degradation of habitat may affect red tree voles not only at the population scale, as is currently the case, but that less obvious consequences for the health of individuals surviving in disturbed or suboptimal habitat are also possible. It is important, therefore, that efforts to conserve this species consider adverse effects of present forest management practices on red tree vole health, as potentially increased disease susceptibility could have detrimental outcomes for this species. In Chapters 3 and 4, I took advantage of a rare and large-scale experiment to test my predictions regarding the negative consequences of habitat degradation for individual animals in more ubiquitous rodent species known for their resilience to environmental disturbance. I investigated the effects of intensive forest management on stress, health, and immunity (Chapter 3), and on the prevalence of infectious diseases transmissible to humans (Chapter 4) in deer mice (Peromyscus maniculatus), Townsend chipmunks (Tamias townsendii), and creeping voles (Microtus oregoni) inhabiting managed forest plots in northwestern Oregon. The experimental design employed allowed me to test the effect of regionally representative forest management practices on health and disease outcomes with important implications for public health. In Chapter 3, I present results which suggest that intensive forest management can have complex, but highly context-dependent effects on the health of wild deer mice. Intensive forest management can shape animals’ condition and reproductive activity, increase levels of stress hormone, and stimulate some but depress other immune responses. However, deer mice are only able to respond to the extreme stressor of this disturbance when underlying environmental conditions are favorable. When inhabiting inherently harsh habitat, mice appear unable to cope with additional disturbance imposed by intensive forest management, and only the fittest mice survive. Finally, in Chapter 4, I identify moderate prevalence of two important and potentially fatal human infections in rodents inhabiting managed forests in northwestern Oregon. In deer mouse populations, Sin Nombre virus was clustered spatially, and prevalence varied between years. But, in the focus of highest infection, the proportion of infected mice, albeit low, appeared to increase with intensity of forest management. For Leptospirosis, I found a similar pattern in creeping voles, but did not observe an association between infection prevalence and forest management in deer mice or chipmunks. I conclude that forest management may drive infectious disease patterns, but that the direction and magnitude of such effects depends on the host-pathogen system. Taken together, my findings indicate that wild animal health can suffer from declines in habitat quality associated with forest management. For a near-threatened species such as the red tree vole, decreases in the availability of food and nesting habitat have the potential to change susceptibility to infection, which could facilitate disease invasion and further threaten populations. For wild animals that serve as reservoirs for human infections, especially abundant and apparently resilient species, impaired health can drive the dynamics of pathogens and increase the risk of transmission to humans and other animals. Although many more questions remain, my work contributes to our understanding of the effects of anthropogenic environmental change for wildlife and human health. Title: Wildlife Health in Managed Forests : Immunity and Infectious Diseases in Wild Rodents of Oregon Author: Hanselmann, Rhea With continual and worldwide human population growth, our impact on the natural environment expands and intensifies every day. We consume natural resources, burn fossil fuels, and release toxic compounds into the air, water, and earth. We build roads that fragment the landscape, construct new settlements, and develop agricultural lands in previously undisturbed areas. And, we introduce non-native species, which compete with and/or prey on native ones. Our actions change the composition of ecosystems by effacing natural environments and decimating plant and animal populations. We have reached a time of unprecedented anthropogenic environmental change. And, while we recognize, and work feverishly to mitigate, countless consequences of our actions, we still lack a profound understanding of just as many of the corollaries of the environmental changes we provoke. One thing we do know is that human-induced changes in environmental conditions can affect health – from individual organisms, to plant and animal populations, all the way to the level of the ecosystem. Yet, the mechanisms underlying such adverse health outcomes are only partially understood. For instance, we know that alterations in the structure of plant and animal communities, the distribution and demographics of populations, and the abundance of individuals can influence the emergence or re-emergence of infectious diseases. Which species are present in a community, where, when, and in what numbers can all determine the dynamics of pathogens, lead to disease outbreaks, and provide opportunities for spillover into new species. However, given the many environmental-, population-, and organism-level factors involved, and the complexity by which these variables interact, detecting and predicting the ultimate consequences for the health of animal, including human, populations remains difficult. Wild animals play important roles in numerous infectious disease cycles, many of which are shared with humans. Considering this and the well-documented effects that human activity can have on wildlife populations, studying the impacts of anthropogenic environmental change on health in wildlife is highly relevant. To understand how human-induced environmental changes affect wildlife health and to make predictions about potential regional or even global consequences for the dynamics of infectious diseases, however, we first need to understand patterns at a local scale. Here, I describe variation in immune function in captive and wild rodent species native to managed forests in northwestern Oregon, and examine how intensive forest management practices affect these and other physiological processes, and the prevalence of infectious diseases, in a large-scale field experiment. In Chapter 2 of this dissertation, I present baseline data on simple immune parameters in an iconic inhabitant of old-growth forests in the Pacific Northwest, the red tree vole (Arborimus longicaudus). I show that both body condition and age are important for immune defenses in this species. Translating these findings to wild populations leads me to predict that degradation of habitat may affect red tree voles not only at the population scale, as is currently the case, but that less obvious consequences for the health of individuals surviving in disturbed or suboptimal habitat are also possible. It is important, therefore, that efforts to conserve this species consider adverse effects of present forest management practices on red tree vole health, as potentially increased disease susceptibility could have detrimental outcomes for this species. In Chapters 3 and 4, I took advantage of a rare and large-scale experiment to test my predictions regarding the negative consequences of habitat degradation for individual animals in more ubiquitous rodent species known for their resilience to environmental disturbance. I investigated the effects of intensive forest management on stress, health, and immunity (Chapter 3), and on the prevalence of infectious diseases transmissible to humans (Chapter 4) in deer mice (Peromyscus maniculatus), Townsend chipmunks (Tamias townsendii), and creeping voles (Microtus oregoni) inhabiting managed forest plots in northwestern Oregon. The experimental design employed allowed me to test the effect of regionally representative forest management practices on health and disease outcomes with important implications for public health. In Chapter 3, I present results which suggest that intensive forest management can have complex, but highly context-dependent effects on the health of wild deer mice. Intensive forest management can shape animals’ condition and reproductive activity, increase levels of stress hormone, and stimulate some but depress other immune responses. However, deer mice are only able to respond to the extreme stressor of this disturbance when underlying environmental conditions are favorable. When inhabiting inherently harsh habitat, mice appear unable to cope with additional disturbance imposed by intensive forest management, and only the fittest mice survive. Finally, in Chapter 4, I identify moderate prevalence of two important and potentially fatal human infections in rodents inhabiting managed forests in northwestern Oregon. In deer mouse populations, Sin Nombre virus was clustered spatially, and prevalence varied between years. But, in the focus of highest infection, the proportion of infected mice, albeit low, appeared to increase with intensity of forest management. For Leptospirosis, I found a similar pattern in creeping voles, but did not observe an association between infection prevalence and forest management in deer mice or chipmunks. I conclude that forest management may drive infectious disease patterns, but that the direction and magnitude of such effects depends on the host-pathogen system. Taken together, my findings indicate that wild animal health can suffer from declines in habitat quality associated with forest management. For a near-threatened species such as the red tree vole, decreases in the availability of food and nesting habitat have the potential to change susceptibility to infection, which could facilitate disease invasion and further threaten populations. For wild animals that serve as reservoirs for human infections, especially abundant and apparently resilient species, impaired health can drive the dynamics of pathogens and increase the risk of transmission to humans and other animals. Although many more questions remain, my work contributes to our understanding of the effects of anthropogenic environmental change for wildlife and human health. Close

• 28. [Article] Evaluating dairy waste management systems' influence on fecal coliform concentration in runoff

  Published November 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Evaluating dairy waste management systems' influence on fecal coliform concentration in runoff Author: Oregon. Dept. of Environmental Quality, Tillamook Soil and Water Conservation District (Or.), Oregon. State Soil and Water Conservation Commission, United States. Environmental Protection Agency, Moore, James A. (James Allan), 1939-, Oregon State University. Agricultural Engineering Dept., Oregon State University. Agricultural Experiment Station Published November 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Evaluating dairy waste management systems' influence on fecal coliform concentration in runoff Author: Oregon. Dept. of Environmental Quality, Tillamook Soil and Water Conservation District (Or.), Oregon. State Soil and Water Conservation Commission, United States. Environmental Protection Agency, Moore, James A. (James Allan), 1939-, Oregon State University. Agricultural Engineering Dept., Oregon State University. Agricultural Experiment Station Published November 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 29. [Article] Influence of hyporheic flow and geomorphology on temperature of a large, gravel-bed river, Clackamas River, Oregon, USA

  The hyporheic zone influences the thermal regime of rivers, buffering temperature by storing and releasing heat over a range of timescales. We examined the relationship between hyporheic exchange and temperature ...

  Citation × Citation Citation Abstract Copy Title: Influence of hyporheic flow and geomorphology on temperature of a large, gravel-bed river, Clackamas River, Oregon, USA Author: Burkholder, Barbara K. The hyporheic zone influences the thermal regime of rivers, buffering temperature by storing and releasing heat over a range of timescales. We examined the relationship between hyporheic exchange and temperature along a 24-km reach of the lower Clackamas River, a large gravel-bed river in northwestern Oregon (median discharge = 75.7 m³/s; minimum mean monthly discharge = 22.7 m³/s in August 2006). With a simple mixing model, we estimated how much hyporheic exchange cools the river during hot summer months. Hyporheic exchange was primarily identified by temperature anomalies, which are patches of water that demonstrate at least a 1 °C temperature difference from the main channel. Forty hyporheic temperature anomalies were identified through field investigations and TIR (Thermal-Infrared-Radiometry) in summer 2006. The location of anomalies was associated with specific geomorphic features, primarily bar channels and bar heads that act as preferential pathways for hyporheic flow. Detailed field characterization and groundwater modeling on three Clackamas gravel bars indicate residence times of hyporheic water can vary from hours to weeks and months. This was largely determined by hydraulic conductivity, which is affected by how recently the gravel bar formed or was reworked. Upscaling of modeled discharges and hydrologic parameters from these bars to the other anomalies on the Clackamas network shows that hyporheic discharge from anomalies comprises a small fraction (<< 1 %) of mainstem discharge, resulting in small river cooling effects (0.012 °C). However, the presence of cooler patches of water within rivers can act as thermal refugia for fish and other aquatic organisms, making the creation or enhancement of hyporheic exchange an attractive method in restoring the thermal regime of rivers. Title: Influence of hyporheic flow and geomorphology on temperature of a large, gravel-bed river, Clackamas River, Oregon, USA Author: Burkholder, Barbara K. The hyporheic zone influences the thermal regime of rivers, buffering temperature by storing and releasing heat over a range of timescales. We examined the relationship between hyporheic exchange and temperature along a 24-km reach of the lower Clackamas River, a large gravel-bed river in northwestern Oregon (median discharge = 75.7 m³/s; minimum mean monthly discharge = 22.7 m³/s in August 2006). With a simple mixing model, we estimated how much hyporheic exchange cools the river during hot summer months. Hyporheic exchange was primarily identified by temperature anomalies, which are patches of water that demonstrate at least a 1 °C temperature difference from the main channel. Forty hyporheic temperature anomalies were identified through field investigations and TIR (Thermal-Infrared-Radiometry) in summer 2006. The location of anomalies was associated with specific geomorphic features, primarily bar channels and bar heads that act as preferential pathways for hyporheic flow. Detailed field characterization and groundwater modeling on three Clackamas gravel bars indicate residence times of hyporheic water can vary from hours to weeks and months. This was largely determined by hydraulic conductivity, which is affected by how recently the gravel bar formed or was reworked. Upscaling of modeled discharges and hydrologic parameters from these bars to the other anomalies on the Clackamas network shows that hyporheic discharge from anomalies comprises a small fraction (<< 1 %) of mainstem discharge, resulting in small river cooling effects (0.012 °C). However, the presence of cooler patches of water within rivers can act as thermal refugia for fish and other aquatic organisms, making the creation or enhancement of hyporheic exchange an attractive method in restoring the thermal regime of rivers. Close

• 30. [Article] Post mortem interval and decomposition rates : biological observations and mathematical analysis

  Entomological evidence can be used for estimating post mortem interval (PMI). Decomposition studies have been conducted throughout the world and these studies have demonstrated that insect succession generally ...

  Citation × Citation Citation Abstract Copy Title: Post mortem interval and decomposition rates : biological observations and mathematical analysis Author: England, David B. Entomological evidence can be used for estimating post mortem interval (PMI). Decomposition studies have been conducted throughout the world and these studies have demonstrated that insect succession generally follows a similar pattern at a taxonomic level, specifically family, but varies at the genus and species levels with respect to geographic and seasonal differences. Insect succession data developed in one region cannot be used generally to estimate PMI in another region. Research has been conducted in a few regions of North America, but at this time there is no known forensic decomposition data for Northwestern Oregon. OBJECTIVES: (1) establish a preliminary insect succession model that can be used by regional law enforcement personal to establish PMI and (2) present a standardized mathematical model that provides a basis for the empirical analysis and comparison of decomposition rates from different regions. RESULTS: Calliphoridae fly species, L. illustris, was the first insect species to arrive and did so in less than 10 minutes PMI. L. illustris, ovipositing took place 6 hours PMI, thus starting the time clock that measures PMI. Secondly, our mathematical analysis gives indication that decomposition has been over simplified. Decomposition has several parameters that have not been elicited; therefore, the next step in our decomposition rate research is to analyze the characteristics of the maggots mass separately from the decomposing carcass. Such controlled experiments would provide valuable understanding of the dynamics of carcass decay. Title: Post mortem interval and decomposition rates : biological observations and mathematical analysis Author: England, David B. Entomological evidence can be used for estimating post mortem interval (PMI). Decomposition studies have been conducted throughout the world and these studies have demonstrated that insect succession generally follows a similar pattern at a taxonomic level, specifically family, but varies at the genus and species levels with respect to geographic and seasonal differences. Insect succession data developed in one region cannot be used generally to estimate PMI in another region. Research has been conducted in a few regions of North America, but at this time there is no known forensic decomposition data for Northwestern Oregon. OBJECTIVES: (1) establish a preliminary insect succession model that can be used by regional law enforcement personal to establish PMI and (2) present a standardized mathematical model that provides a basis for the empirical analysis and comparison of decomposition rates from different regions. RESULTS: Calliphoridae fly species, L. illustris, was the first insect species to arrive and did so in less than 10 minutes PMI. L. illustris, ovipositing took place 6 hours PMI, thus starting the time clock that measures PMI. Secondly, our mathematical analysis gives indication that decomposition has been over simplified. Decomposition has several parameters that have not been elicited; therefore, the next step in our decomposition rate research is to analyze the characteristics of the maggots mass separately from the decomposing carcass. Such controlled experiments would provide valuable understanding of the dynamics of carcass decay. Close