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• 1. [Article] Historical changes in stream habitats in the Columbia River basin

  Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current ...

  Citation × Citation Citation Abstract Copy Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Title: Historical changes in stream habitats in the Columbia River basin Author: McIntosh, Bruce A. Knowledge of how stream habitats change over time in natural and human-influenced ecosystems at large, regional scales is currently limited. A historical stream survey (1934-1945) was compared to current surveys to assess changes in poo1 habitats in the Columbia River basin. Streams from across the basin, representing a wide range of geologies, stream sizes and land-use histories, were used to evaluate habitat change. We classified streams as managed or unmanaged, based on their land-use histories. Managed basins were watersheds managed predominantly for multiple-use (e.g., timber harvest, livestock grazing) and unmanaged basins were minimally affected by human disturbance (e.g., wilderness/roadless areas). The quantity and quality of pool habitats increased or remained the same in unmanaged streams, and decreased in managed streams since the 1930s. Despite differences in stream size and land-use history, the magnitude and direction of theses changes were consistent. In addition, the decrease in pool habitats did not differ between public and private lands. Ecoregions were used to assess regional patterns to these changes. Our analysis showed that pool habitats decreased in all Ecoregions except the North Cascades Ecoregion. Regional land-use histories were documented for the study streams. The overgrazing of most rangelands had been documented by 1900. Grazing practices began to change after 1930, but current information suggests that while uplands have improved, riparian areas have not. By World War II, stream habitats had been affected by the loss of riparian vegetation, large woody debris, and aquatic habitats due to splash dams, log drives, and riparian timber harvest. Timber harvest expanded to the uplands after World War II, as the demand for timber expanded. Rapidly developing road networks increased runoff and sedimentation, which continued the impact of timber harvest on already damaged stream ecosystems. Almost 90% of managed streams had roads along the channel or within the floodplain. "Stream improvements," such as channelization and stream cleaning, also affected stream ecosystems. We concluded that the chronic and persistent effects of land-use practices had simplified stream channels and reduced habitat complexity in most managed watersheds in the Columbia River basin. Close

• 2. [Article] Historical changes in anadromous fish habitat in the Upper Grande Ronde River, Oregon, 1941-1990

  The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream ...

  Citation × Citation Citation Abstract Copy Title: Historical changes in anadromous fish habitat in the Upper Grande Ronde River, Oregon, 1941-1990 Author: McIntosh, Bruce A. The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream habitat conditions for anadromous salmonids (Oncorhynchus spp.) throughout the Columbia River Basin. The survey systematically inventoried 158 km of streams within the 3000 km2 watershed. Stream habitat was degraded from land-use activities (riparian timber harvest, splash dams, stream channelization, livestock grazing, and mining) prior to the 1941 survey. A 1990 resurvey determined how stream habitat conditions had continued to change. The historical survey and the 1990 resurvey inventoried streams according to pool and substrate characteristics. Pools were classified by size and depth criteria, while substrate was divided into size-classes. Losses in total pools/km (> 20m2 area and > 0.5 m depth) ranged from 43 to 83% (mean = 65%, 12.2 to 4.31km), while the loss in large pools/km (> 20m2 and > 1.0 m depth) ranged from 20 to 89% (mean = 68%, 6.2 to 2.0/1cm) for individual streams. The loss of variability in pool frequencies from 1941 to 1990 (total pools/km a2 = 43.9 to 2.8, large pools/km a2 = 23.2 to 3.2) demonstrates that stream channels have become less diverse. Classifying streams by reach types indicated that the decline in pool frequencies was not significantly related to geomorphic constraints. Substrate composition appears to have shifted toward smaller size-classes, with an increase in fine sediments (< 6mm) in the headwaters. Livestock grazing declined 78% (229,000 to 51,000 aum) from 1911 to 1990, while annual timber harvest increased 172% (36 to 98 mmbf) from the pre-survey period (1896-1940) to the post-survey period (1940-1990). Road densities have increased concurrent with timber harvest, currently averaging 4 miles/mile2. Base discharge has increased 51% (18.5 to 28.0 cfs), while there has been a 27% decrease in annual precipitation (22.0" to 16.0") and snowpack (April 1 water equivalent) (15.0" to 10.5") from 1941 to 1990. In an era of presumably improving management (1941-1990), large-scale losses in the fish habitat necessary for the continued viability of resident and anadromous fish populations continued to occur. Title: Historical changes in anadromous fish habitat in the Upper Grande Ronde River, Oregon, 1941-1990 Author: McIntosh, Bruce A. The U.S. Bureau of Fisheries (now National Marine Fisheries Service) conducted stream habitat surveys in the Upper Grande Ronde River Basin in 1941. This survey was part of an extensive inventory of stream habitat conditions for anadromous salmonids (Oncorhynchus spp.) throughout the Columbia River Basin. The survey systematically inventoried 158 km of streams within the 3000 km2 watershed. Stream habitat was degraded from land-use activities (riparian timber harvest, splash dams, stream channelization, livestock grazing, and mining) prior to the 1941 survey. A 1990 resurvey determined how stream habitat conditions had continued to change. The historical survey and the 1990 resurvey inventoried streams according to pool and substrate characteristics. Pools were classified by size and depth criteria, while substrate was divided into size-classes. Losses in total pools/km (> 20m2 area and > 0.5 m depth) ranged from 43 to 83% (mean = 65%, 12.2 to 4.31km), while the loss in large pools/km (> 20m2 and > 1.0 m depth) ranged from 20 to 89% (mean = 68%, 6.2 to 2.0/1cm) for individual streams. The loss of variability in pool frequencies from 1941 to 1990 (total pools/km a2 = 43.9 to 2.8, large pools/km a2 = 23.2 to 3.2) demonstrates that stream channels have become less diverse. Classifying streams by reach types indicated that the decline in pool frequencies was not significantly related to geomorphic constraints. Substrate composition appears to have shifted toward smaller size-classes, with an increase in fine sediments (< 6mm) in the headwaters. Livestock grazing declined 78% (229,000 to 51,000 aum) from 1911 to 1990, while annual timber harvest increased 172% (36 to 98 mmbf) from the pre-survey period (1896-1940) to the post-survey period (1940-1990). Road densities have increased concurrent with timber harvest, currently averaging 4 miles/mile2. Base discharge has increased 51% (18.5 to 28.0 cfs), while there has been a 27% decrease in annual precipitation (22.0" to 16.0") and snowpack (April 1 water equivalent) (15.0" to 10.5") from 1941 to 1990. In an era of presumably improving management (1941-1990), large-scale losses in the fish habitat necessary for the continued viability of resident and anadromous fish populations continued to occur. Close

• 3. [Article] The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon

  Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream ...

  Citation × Citation Citation Abstract Copy Title: The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon Author: Kibler, Kelly Maren Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream can increase the amount of solar radiation the stream receives, which can elevate stream temperatures and impair aquatic habitat. Oregon Forest Practice Rules mandate that forest operators leave Riparian Management Areas (RMAs) adjacent to streams in order to minimize the water quality impacts from forest harvesting. However, RMAs that contain overstory merchantable conifers are not required for small non-fish-bearing streams in Oregon, thus there is potential for increases in stream temperature to occur in headwater streams after harvesting. There is concern that increases in stream temperatures and changes to onsite processes in non-fish-bearing, headwater streams may propagate downstream and impair habitat in fish-bearing streams. The objectives of the following work are to assess the effects of contemporary forest management practices on stream temperatures of small non-fish-bearing headwater streams and to develop new knowledge regarding the physical processes that control reach-level stream temperature patterns. Summer stream temperatures were measured for five years in six headwater streams in the Hinkle Creek basin in southern Oregon. After four years, four of the streams were harvested and vegetated RMAs were not left between the streams and harvest units. The watersheds of the two remaining streams were not disturbed. Post-harvest stream temperatures were monitored for one year in all six streams. Each harvested stream was paired with one unharvested stream and regression relationships for maximum, minimum and mean daily stream temperatures were developed. Changes to temperatures of harvested streams were detected by comparing the mean pre-harvest regression relationship to the mean post-harvest relationship. Change detection analyses that considered the mean response among all four harvested streams indicated that maximum daily stream temperatures did not increase after harvesting, but that minimum and mean daily temperatures decreased significantly after harvesting. Additionally, diel stream temperature fluctuations were significantly greater one year after harvesting. Pre- and post-harvest surveys of canopy closure in the harvested and unharvested streams were completed in order to compare levels of stream shading before and after harvest. The post-harvest survey quantified canopy closure from remaining overstory vegetation as well as from logging slash that partially covered the harvested streams. The surveys indicated that mean overstory canopy closure in the harvested streams decreased by 84% as a result of the harvest, but as the logging slash provided considerable cover, total canopy closure decreased by only 20%. It is possible that the logging slash effectively attenuated solar radiation and prevented extreme temperature increases in the harvested streams. However, it is likely that streamflow increased after harvesting and that the increased streamflow also prevented increases to maximum temperatures and contributed to lower minimum and mean stream temperatures. Title: The influence of contemporary forest harvesting on summer stream temperatures in headwater streams of Hinkle Creek, Oregon Author: Kibler, Kelly Maren Stream temperature is a water quality parameter that directly influences the quality of aquatic habitat, particularly for cold-water species such as Pacific salmonids. Forest harvesting adjacent to a stream can increase the amount of solar radiation the stream receives, which can elevate stream temperatures and impair aquatic habitat. Oregon Forest Practice Rules mandate that forest operators leave Riparian Management Areas (RMAs) adjacent to streams in order to minimize the water quality impacts from forest harvesting. However, RMAs that contain overstory merchantable conifers are not required for small non-fish-bearing streams in Oregon, thus there is potential for increases in stream temperature to occur in headwater streams after harvesting. There is concern that increases in stream temperatures and changes to onsite processes in non-fish-bearing, headwater streams may propagate downstream and impair habitat in fish-bearing streams. The objectives of the following work are to assess the effects of contemporary forest management practices on stream temperatures of small non-fish-bearing headwater streams and to develop new knowledge regarding the physical processes that control reach-level stream temperature patterns. Summer stream temperatures were measured for five years in six headwater streams in the Hinkle Creek basin in southern Oregon. After four years, four of the streams were harvested and vegetated RMAs were not left between the streams and harvest units. The watersheds of the two remaining streams were not disturbed. Post-harvest stream temperatures were monitored for one year in all six streams. Each harvested stream was paired with one unharvested stream and regression relationships for maximum, minimum and mean daily stream temperatures were developed. Changes to temperatures of harvested streams were detected by comparing the mean pre-harvest regression relationship to the mean post-harvest relationship. Change detection analyses that considered the mean response among all four harvested streams indicated that maximum daily stream temperatures did not increase after harvesting, but that minimum and mean daily temperatures decreased significantly after harvesting. Additionally, diel stream temperature fluctuations were significantly greater one year after harvesting. Pre- and post-harvest surveys of canopy closure in the harvested and unharvested streams were completed in order to compare levels of stream shading before and after harvest. The post-harvest survey quantified canopy closure from remaining overstory vegetation as well as from logging slash that partially covered the harvested streams. The surveys indicated that mean overstory canopy closure in the harvested streams decreased by 84% as a result of the harvest, but as the logging slash provided considerable cover, total canopy closure decreased by only 20%. It is possible that the logging slash effectively attenuated solar radiation and prevented extreme temperature increases in the harvested streams. However, it is likely that streamflow increased after harvesting and that the increased streamflow also prevented increases to maximum temperatures and contributed to lower minimum and mean stream temperatures. Close

• 4. [Article] Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains

  Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington ...

  Citation × Citation Citation Abstract Copy Title: Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains Author: Goetz, Frederick Allen Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington from 1989 to 1991, using day snorkeling, night snorkeling, and electrofishing. These methods were selected after a preliminary diel streamside study of juvenile bull trout showed fry (age 0) counts were significantly higher (P<0.00l) during the day, while counts of juvenile fish (age 1 and 2) were significantly higher (P<0.00l) at night. The highest counts of juveniles occurred during a "quiet period" immediately after dusk, during which time fish were inactive, out of cover, and easily counted with underwater flashlights. In a comparison of four sampling methods on Jack Creek, electrofishing was significantly correlated (P<0.05) with day (r=0.8l) and night (r=0.89) snorkeling counts, but not with streambank counts. In a comparison of day and night snorkeling in 10 streams, total density estimates were significantly greater (P<0.0l) for night snorkeling than day. The diel study and sampling methods comparison suggested surveys of distribution and habitat use of bull trout should include night surveys as well as day. Distribution surveys found that, except for one stream, juvenile bull trout were found only in, or near, spring-fed areas created by recent lava flows. Presence of bull trout in a stream was related to cold groundwater temperatures, as they were not found in streams with temperatures above 14°C. Distribution of bull trout in Oregon and Washington followed a pattern of decreasing elevation with increasing latitude and longitude(Ra=-0.9l6) Presence at lower than expected elevations were explained when groundwater temperatures were predicted from mean annual air temperatures. Actual water temperatures for these spring-fed streams were significantly lower (p<0.00l) than predicted based on elevation, latitude, and longitude. Comparison of historical distribution of bull trout showed extant bull trout were found in the Willamette and Deschutes River Basins of Oregon, respectively, in only 26.2 and 56.2% of their former ranges. Factors associated with bull trout demise in Oregon Cascade streams were (1) isolation and inundation of spring-fed stream habitat by water control structures, (2) introduction of brook trout and brown trout, and (3) large flood events and habitat degradation. Juvenile habitat use was analyzed at the macrohabitat (habitat unit) level in five river basins. Diel and seasonal microhabitat use was also documented for one spring-fed stream, Jack Creek. There was a clear difference in habitat use day and night, associated with the low water temperature of the spring-fed streams (mean=8.0°C). All habitat unit types (pool, riffle, glide, side channel) were used day and night, but bull trout only elected to use side channels in both time periods. Bull trout were found at night in (1) a higher percentage of habitat units, (2) in higher densities by unit, and (3) in increasing numbers with increasing habitat unit area. In Jack Creek, bull trout elected to use shallow water depths, low mean velocities, instream woody debris, and small substrates. Title: Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in the Cascade Mountains Author: Goetz, Frederick Allen Distribution and juvenile habitat use of bull trout (Salvelinus confluentus) were surveyed in selected areas of the Upper Willamette, Deschutes, upper Yakima, and upper Cedar River basins in Oregon and Washington from 1989 to 1991, using day snorkeling, night snorkeling, and electrofishing. These methods were selected after a preliminary diel streamside study of juvenile bull trout showed fry (age 0) counts were significantly higher (P<0.00l) during the day, while counts of juvenile fish (age 1 and 2) were significantly higher (P<0.00l) at night. The highest counts of juveniles occurred during a "quiet period" immediately after dusk, during which time fish were inactive, out of cover, and easily counted with underwater flashlights. In a comparison of four sampling methods on Jack Creek, electrofishing was significantly correlated (P<0.05) with day (r=0.8l) and night (r=0.89) snorkeling counts, but not with streambank counts. In a comparison of day and night snorkeling in 10 streams, total density estimates were significantly greater (P<0.0l) for night snorkeling than day. The diel study and sampling methods comparison suggested surveys of distribution and habitat use of bull trout should include night surveys as well as day. Distribution surveys found that, except for one stream, juvenile bull trout were found only in, or near, spring-fed areas created by recent lava flows. Presence of bull trout in a stream was related to cold groundwater temperatures, as they were not found in streams with temperatures above 14°C. Distribution of bull trout in Oregon and Washington followed a pattern of decreasing elevation with increasing latitude and longitude(Ra=-0.9l6) Presence at lower than expected elevations were explained when groundwater temperatures were predicted from mean annual air temperatures. Actual water temperatures for these spring-fed streams were significantly lower (p<0.00l) than predicted based on elevation, latitude, and longitude. Comparison of historical distribution of bull trout showed extant bull trout were found in the Willamette and Deschutes River Basins of Oregon, respectively, in only 26.2 and 56.2% of their former ranges. Factors associated with bull trout demise in Oregon Cascade streams were (1) isolation and inundation of spring-fed stream habitat by water control structures, (2) introduction of brook trout and brown trout, and (3) large flood events and habitat degradation. Juvenile habitat use was analyzed at the macrohabitat (habitat unit) level in five river basins. Diel and seasonal microhabitat use was also documented for one spring-fed stream, Jack Creek. There was a clear difference in habitat use day and night, associated with the low water temperature of the spring-fed streams (mean=8.0°C). All habitat unit types (pool, riffle, glide, side channel) were used day and night, but bull trout only elected to use side channels in both time periods. Bull trout were found at night in (1) a higher percentage of habitat units, (2) in higher densities by unit, and (3) in increasing numbers with increasing habitat unit area. In Jack Creek, bull trout elected to use shallow water depths, low mean velocities, instream woody debris, and small substrates. Close

• 5. [Article] Results and review of a riparian survey method used in eastern Oregon

  In the late 1970s, approximately 400 miles of streams were inventoried by the Prineville District of the Bureau of Land Management for in-stream and riparian condition. During the summer of 1994, the riparian ...

  Citation × Citation Citation Abstract Copy Title: Results and review of a riparian survey method used in eastern Oregon Author: Rasmussen, Christine G. In the late 1970s, approximately 400 miles of streams were inventoried by the Prineville District of the Bureau of Land Management for in-stream and riparian condition. During the summer of 1994, the riparian portion of the survey was repeated on 17 of the original streams miles, contained within 11 stream sections where grazing strategies had been altered. This project was a case study designed to evaluate efficiency of the original methods and identify factors involved in individual stream responses. The streams selected to be resurveyed varied in community types present, gradient, elevation, grazing system, disturbance history, influence of beaver, and restoration efforts. Community types were identified by their major components (grass-shrub, sedge-rush) and measured for length and width. Length of stream bank damage was estimated and causes noted. Stream sections were surveyed between matching points for the 1976-78 and 1994 surveys. Most streams had increases in riparian area and decreases in bank damage and lengths of cutbanks, suggesting an upward trend in condition. The bank damage, riparian area, and community identification portions of the survey were identified as useful though composition measurements were determined to be less dependable and repeatable. Title: Results and review of a riparian survey method used in eastern Oregon Author: Rasmussen, Christine G. In the late 1970s, approximately 400 miles of streams were inventoried by the Prineville District of the Bureau of Land Management for in-stream and riparian condition. During the summer of 1994, the riparian portion of the survey was repeated on 17 of the original streams miles, contained within 11 stream sections where grazing strategies had been altered. This project was a case study designed to evaluate efficiency of the original methods and identify factors involved in individual stream responses. The streams selected to be resurveyed varied in community types present, gradient, elevation, grazing system, disturbance history, influence of beaver, and restoration efforts. Community types were identified by their major components (grass-shrub, sedge-rush) and measured for length and width. Length of stream bank damage was estimated and causes noted. Stream sections were surveyed between matching points for the 1976-78 and 1994 surveys. Most streams had increases in riparian area and decreases in bank damage and lengths of cutbanks, suggesting an upward trend in condition. The bank damage, riparian area, and community identification portions of the survey were identified as useful though composition measurements were determined to be less dependable and repeatable. Close

• 6. [Article] Hydrologic integration of forest roads with stream networks in two basins, western Cascades, Oregon

  This study assessed how logging-access roads may have contributed to observed historical increases in peak discharges associated with small and large logged basins in the western Cascades of Oregon. The ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic integration of forest roads with stream networks in two basins, western Cascades, Oregon Author: Wemple, Beverly C. This study assessed how logging-access roads may have contributed to observed historical increases in peak discharges associated with small and large logged basins in the western Cascades of Oregon. The study was conducted on the Lookout Creek (62km²) and the upper Blue River (118km²) basins. Potential road effects on hydrology were examined using a combination of field surveys and spatial modeling with a geographic information system (GIS). Road networks were similar in both basins with respect to hillslope position, orientation, and stream crossings, but roads in Blue River were constructed one or two decades later than roads in Lookout Creek. A total of 20% (62 km) of the road length was sampled to assess routing of surface flow, using 31 2-km transects stratified by decade of construction and hillslope position. Along each transect, ditches and culvert outlets were examined and this information used to predict the probable routing of water to (1) existing stream channels, (2) newly eroded gullies downslope of culvert outlets, or (3) subsurface flow. Nearly 60% of the surveyed road length appeared to route water directly to stream channels or into gullies. Over time, the length of road connected to stream crossings has decreased, while the length of road discharging runoff that reinfiltrates to subsurface flow has increased, as roads have progressed up hillslopes and onto ridges in Lookout Creek and Blue River. The relatively constant proportion of the road network draining to gullies over time suggests that roads have the potential to become integrated into stream networks, even when constructed on unchannelled hillslope positions. An extended stream network, assumed to exist under storm conditions, was simulated for the basins using a digital elevation model. Although gullies and ditches differ from natural channels, extrapolation of field surveys using the GIS suggested that roads might extend the stream network by as much as 40% during storm events. It is hypothesized that such an effect could decrease the time of concentration of stormflow and contribute to higher peak discharges observed after clearcutting and road construction in these basins. Differences in the magnitude of road effects on peak flow generation may occur among road systems according to hillslope position of roads, road age, soil saturation, geologic substrate, and climate. These differences may explain the range of observed results from paired-basin studies examining road effects on hydrologic response. Title: Hydrologic integration of forest roads with stream networks in two basins, western Cascades, Oregon Author: Wemple, Beverly C. This study assessed how logging-access roads may have contributed to observed historical increases in peak discharges associated with small and large logged basins in the western Cascades of Oregon. The study was conducted on the Lookout Creek (62km²) and the upper Blue River (118km²) basins. Potential road effects on hydrology were examined using a combination of field surveys and spatial modeling with a geographic information system (GIS). Road networks were similar in both basins with respect to hillslope position, orientation, and stream crossings, but roads in Blue River were constructed one or two decades later than roads in Lookout Creek. A total of 20% (62 km) of the road length was sampled to assess routing of surface flow, using 31 2-km transects stratified by decade of construction and hillslope position. Along each transect, ditches and culvert outlets were examined and this information used to predict the probable routing of water to (1) existing stream channels, (2) newly eroded gullies downslope of culvert outlets, or (3) subsurface flow. Nearly 60% of the surveyed road length appeared to route water directly to stream channels or into gullies. Over time, the length of road connected to stream crossings has decreased, while the length of road discharging runoff that reinfiltrates to subsurface flow has increased, as roads have progressed up hillslopes and onto ridges in Lookout Creek and Blue River. The relatively constant proportion of the road network draining to gullies over time suggests that roads have the potential to become integrated into stream networks, even when constructed on unchannelled hillslope positions. An extended stream network, assumed to exist under storm conditions, was simulated for the basins using a digital elevation model. Although gullies and ditches differ from natural channels, extrapolation of field surveys using the GIS suggested that roads might extend the stream network by as much as 40% during storm events. It is hypothesized that such an effect could decrease the time of concentration of stormflow and contribute to higher peak discharges observed after clearcutting and road construction in these basins. Differences in the magnitude of road effects on peak flow generation may occur among road systems according to hillslope position of roads, road age, soil saturation, geologic substrate, and climate. These differences may explain the range of observed results from paired-basin studies examining road effects on hydrologic response. Close

• 7. [Article] Year 2000 Timber Sales - Confederated Tribes on Grand Ronde : Biological Opinion

  The Natural Resources Division (NRD) of the Confederated Tribes of Grand Ronde (CTGR), in cooperation with the Bureau of Indian Affairs (BIA), proposes the regeneration harvest and commercial thinning ...

  Citation × Citation Citation Abstract Copy Title: Year 2000 Timber Sales - Confederated Tribes on Grand Ronde : Biological Opinion The Natural Resources Division (NRD) of the Confederated Tribes of Grand Ronde (CTGR), in cooperation with the Bureau of Indian Affairs (BIA), proposes the regeneration harvest and commercial thinning of four timber sales on the Reservation of The Confederated Tribes of Grand Ronde (CTGR). The CTGR has a 20-year management agreement with the BIA. For the purposes of this consultation the BIA is the action agency. The proposed timber harvest units are in the South Yamhill River subbasin, which supports two species listed by the National Marine Fisheries Service (NMFS) as threatened under the Federal Endangered Species Act (ESA). Upper Willamette River (UWR) chinook salmon (Oncorhynchus tshawytscha) were listed as threatened under the ESA on May 24, 1999. Upper Willamette River (UWR) steelhead (Oncorhynchus mykiss) were listed as threatened under the ESA on March 25, 1999. Critical habitat for both of these species was designated on February 16, 2000 (effective on March 17, 2000). According to the BA, UWR chinook do not currently reside in the action area and there is no recorded data indicating they were present historically. The nearest known occurrence of UWR chinook is near the confluence of Salt creek and the South Yamhill River, over 40 stream miles from the Reservation. Juvenile UWR steelhead reside within the action area and are known to occur in streams on the reservation. Based on the presence of juveniles, CTGR staff suspect that adult UWR steelhead spawn in streams on the Reservation, although little spawning survey work has been done. Title: Year 2000 Timber Sales - Confederated Tribes on Grand Ronde : Biological Opinion The Natural Resources Division (NRD) of the Confederated Tribes of Grand Ronde (CTGR), in cooperation with the Bureau of Indian Affairs (BIA), proposes the regeneration harvest and commercial thinning of four timber sales on the Reservation of The Confederated Tribes of Grand Ronde (CTGR). The CTGR has a 20-year management agreement with the BIA. For the purposes of this consultation the BIA is the action agency. The proposed timber harvest units are in the South Yamhill River subbasin, which supports two species listed by the National Marine Fisheries Service (NMFS) as threatened under the Federal Endangered Species Act (ESA). Upper Willamette River (UWR) chinook salmon (Oncorhynchus tshawytscha) were listed as threatened under the ESA on May 24, 1999. Upper Willamette River (UWR) steelhead (Oncorhynchus mykiss) were listed as threatened under the ESA on March 25, 1999. Critical habitat for both of these species was designated on February 16, 2000 (effective on March 17, 2000). According to the BA, UWR chinook do not currently reside in the action area and there is no recorded data indicating they were present historically. The nearest known occurrence of UWR chinook is near the confluence of Salt creek and the South Yamhill River, over 40 stream miles from the Reservation. Juvenile UWR steelhead reside within the action area and are known to occur in streams on the reservation. Based on the presence of juveniles, CTGR staff suspect that adult UWR steelhead spawn in streams on the Reservation, although little spawning survey work has been done. Close

• 8. [Article] Is the past present? Historical splash-dam mapping and stream disturbance detection in the Oregon Coastal Province

  Severe scouring from splash damming was one of the earliest reported forms of widespread anthropogenic disturbance in streams of the Pacific Northwest, USA. Splash damming was a common method of log transport ...

  Citation × Citation Citation Abstract Copy Title: Is the past present? Historical splash-dam mapping and stream disturbance detection in the Oregon Coastal Province Author: Miller, Rebecca R. Severe scouring from splash damming was one of the earliest reported forms of widespread anthropogenic disturbance in streams of the Pacific Northwest, USA. Splash damming was a common method of log transport in western Oregon from the 1880s through the 1950s. Before being released in large freshets to downstream lumber mills, water and logs were stored in reservoirs behind splash dams. Further protocol called for dynamiting downstream obstacles such as large boulders and natural logjams. In recent literature, the legacy effect of historical splash damming is proposed as contributing to currently poor habitat conditions for lotic species, such as Pacific salmon (Oncorhynchus spp.), but this has never been formally evaluated at a regional scale. In this study, all known splash-dam sites and log drives in western Oregon were recorded in a geo-database and mapped in ArcGIS 9.3 at the 1:24,000 scale. Splash-dam sites were located through intense archival, historical aerial photograph and field searches. The final splash-dam map was overlaid with regionally available continuous and probabilistic stream surveys. After accounting for basin area and channel slope, in-channel variables were compared between reaches upstream and downstream of splash dams (within-basin analysis) and between reaches in splashed and not-splashed basins (among-basin analysis). Only data from sites located in a forested land cover and sedimentary rock type in the Oregon Coastal Province were analyzed. A significant difference (α = 0.1) was seen in either within- or among-basin analyses for each evaluated category of in-channel variable (geomorphology, substrates, pools, and channel complexity). Both analyses demonstrated significantly more bedrock and fewer deep pools in splashed reaches. In the among-basin analysis, three times fewer pieces of key large wood were found in splashed reaches (p = 0.07). Many of the in-channel variables that demonstrated significant differences are regarded as indicators of salmon habitat quality. This is the first regional study to document that splash-dam legacy effects still persist on evaluated stream reaches 50-130 years after the practice ceased. Further, I detected a splash-damming signal in widely used regional monitoring datasets, which suggests that legacy effects should be considered in future applications of these datasets. Splash-damming impacts are pervasive and persistent throughout the Oregon Coastal Province; consequently, extensive and intensive restoration measures may be necessary to accelerate recovery of certain stream habitat characteristics in streams where splash damming and log drives occurred. This study demonstrates the importance of including archival information in modern-day studies, and that history can account for significant variation in the stream environment. Title: Is the past present? Historical splash-dam mapping and stream disturbance detection in the Oregon Coastal Province Author: Miller, Rebecca R. Severe scouring from splash damming was one of the earliest reported forms of widespread anthropogenic disturbance in streams of the Pacific Northwest, USA. Splash damming was a common method of log transport in western Oregon from the 1880s through the 1950s. Before being released in large freshets to downstream lumber mills, water and logs were stored in reservoirs behind splash dams. Further protocol called for dynamiting downstream obstacles such as large boulders and natural logjams. In recent literature, the legacy effect of historical splash damming is proposed as contributing to currently poor habitat conditions for lotic species, such as Pacific salmon (Oncorhynchus spp.), but this has never been formally evaluated at a regional scale. In this study, all known splash-dam sites and log drives in western Oregon were recorded in a geo-database and mapped in ArcGIS 9.3 at the 1:24,000 scale. Splash-dam sites were located through intense archival, historical aerial photograph and field searches. The final splash-dam map was overlaid with regionally available continuous and probabilistic stream surveys. After accounting for basin area and channel slope, in-channel variables were compared between reaches upstream and downstream of splash dams (within-basin analysis) and between reaches in splashed and not-splashed basins (among-basin analysis). Only data from sites located in a forested land cover and sedimentary rock type in the Oregon Coastal Province were analyzed. A significant difference (α = 0.1) was seen in either within- or among-basin analyses for each evaluated category of in-channel variable (geomorphology, substrates, pools, and channel complexity). Both analyses demonstrated significantly more bedrock and fewer deep pools in splashed reaches. In the among-basin analysis, three times fewer pieces of key large wood were found in splashed reaches (p = 0.07). Many of the in-channel variables that demonstrated significant differences are regarded as indicators of salmon habitat quality. This is the first regional study to document that splash-dam legacy effects still persist on evaluated stream reaches 50-130 years after the practice ceased. Further, I detected a splash-damming signal in widely used regional monitoring datasets, which suggests that legacy effects should be considered in future applications of these datasets. Splash-damming impacts are pervasive and persistent throughout the Oregon Coastal Province; consequently, extensive and intensive restoration measures may be necessary to accelerate recovery of certain stream habitat characteristics in streams where splash damming and log drives occurred. This study demonstrates the importance of including archival information in modern-day studies, and that history can account for significant variation in the stream environment. Close

• 9. [Article] Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape

  Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors ...

  Citation × Citation Citation Abstract Copy Title: Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape Author: Schweickert, Tina K. Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors of change become increasingly useful. This study considers competing schools of interpretation about human impacts on ecological landscapes and develops a case study of one thirty-six square mile township in Oregon’s Waldo Hills. Built on evidence from 1851 surveyor notes, maps, journals, aerial photos, interviews, and contemporary environmental and ecological data, this study demonstrates a transformation from ecologically diverse ecosystems under the management of native peoples to ecologically depressed monoculture landscapes under industrialized agriculture. This thesis argues that the fundamental beliefs of human societies (i.e., worldviews) become expressed in the landscape. The nature-as-community view of the Kalapuya Indians resulted in a complex, curvilinear mosaic of prairie, savanna, and woodland. The individualized and rationalized view of the Euroamericans resulted in a simplified landscape of squared-off fields, channelized streams, and roads aligned to the survey grid. Thomas Jefferson’s rectangular survey, built on the ‘virtuous square’, is examined as a symbolic and tangible instrument of rapid expansion and exploitation across the American West. Understanding that worldviews become expressed in physical conditions may benefit those working to create sustainable futures; i.e., long-term and widespread ecological improvements will likely succeed only if society at large shares a fundamental belief in the value of healthy ecosystems. Title: Nature in chains : the effects of Thomas Jefferson’s rectangular survey on a Pacific Northwest landscape Author: Schweickert, Tina K. Understanding the impact of humans on the environment has long been a topic of scholarly interest and debate. As environmental problems mount, accounts of historic ecological conditions and the factors of change become increasingly useful. This study considers competing schools of interpretation about human impacts on ecological landscapes and develops a case study of one thirty-six square mile township in Oregon’s Waldo Hills. Built on evidence from 1851 surveyor notes, maps, journals, aerial photos, interviews, and contemporary environmental and ecological data, this study demonstrates a transformation from ecologically diverse ecosystems under the management of native peoples to ecologically depressed monoculture landscapes under industrialized agriculture. This thesis argues that the fundamental beliefs of human societies (i.e., worldviews) become expressed in the landscape. The nature-as-community view of the Kalapuya Indians resulted in a complex, curvilinear mosaic of prairie, savanna, and woodland. The individualized and rationalized view of the Euroamericans resulted in a simplified landscape of squared-off fields, channelized streams, and roads aligned to the survey grid. Thomas Jefferson’s rectangular survey, built on the ‘virtuous square’, is examined as a symbolic and tangible instrument of rapid expansion and exploitation across the American West. Understanding that worldviews become expressed in physical conditions may benefit those working to create sustainable futures; i.e., long-term and widespread ecological improvements will likely succeed only if society at large shares a fundamental belief in the value of healthy ecosystems. Close

• 10. [Article] Factors influencing pool morphology in Oregon coastal streams

  Pool morphology was surveyed in 19 stream sections within the central Oregon Coast Range. Pool locations, sizes, spacings, numbers, and factors affecting pool formation were determined for each stream ...

  Citation × Citation Citation Abstract Copy Title: Factors influencing pool morphology in Oregon coastal streams Author: Stack, William Robert Pool morphology was surveyed in 19 stream sections within the central Oregon Coast Range. Pool locations, sizes, spacings, numbers, and factors affecting pool formation were determined for each stream section. All sections were underlain by sedimentary rocks, had drainage areas ranging from 1.3 to 17.3 km², and had average water surface slopes from 0.5 to 5.6%. Stream sections were divided into two categories: (1) low timber harvest (<20% of watershed area harvested) and (2) high timber harvest (>45% of watershed area harvested). A "Rapid Bed Profile" (REP) technique was developed to measure residual pool characteristics in each stream section. The REP technique is a survey method that requires only thalweg depths and the average reach gradient. The technique was effective for classifying pools since it is objective, independent of flow, accurate, and time-efficient. Residual pool size characteristics (e.g., volume) for the low timber harvest stream sections were positively correlated to a power function of drainage area. Stream sections with beaver dams, especially those with at least 10% of their reach length in beaver-caused pools, typically had larger residual pools. Pool size characteristics for high timber harvest stream sections were not different from low timber harvest stream sections. The average spacing between residual pools was positively correlated to a power function of drainage area for the low timber harvest stream sections (a negative correlation was found between the number of pools and drainage area). High timber harvest stream sections may be associated with an increased spacing and a decreased number of pools for larger watersheds (i.e., greater than 8 km²). However, the potential effects of previous large storms, changes in timber management practices, and/or the small number of streams surveyed precluded a definitive conclusion. The frequency of occurrence of pool forming processes (e.g., plunge, deflection) was correlated with average water surface slope for the low timber harvest stream sections. The percentage of plunge and impoundment processes increased as water surface slope increased while the percentage of deflection and underflow processes decreased. Two high timber harvest streams had a higher percentage of plunge pools than expected based on the relationships established for the low timber harvest streams. The frequency of occurrence of wood and boulder pool forming elements was correlated with an index of stream power (drainage area times average water slope) for the low timber harvest stream sections. As the stream power index increased, the relative frequency of wood-formed pools decreased while boulder-formed pools increased. Wood and boulder combined, generally, made up 80% of the pool forming elements. The frequency of occurrence of pool forming elements was not different between low and high timber harvest stream sections. Title: Factors influencing pool morphology in Oregon coastal streams Author: Stack, William Robert Pool morphology was surveyed in 19 stream sections within the central Oregon Coast Range. Pool locations, sizes, spacings, numbers, and factors affecting pool formation were determined for each stream section. All sections were underlain by sedimentary rocks, had drainage areas ranging from 1.3 to 17.3 km², and had average water surface slopes from 0.5 to 5.6%. Stream sections were divided into two categories: (1) low timber harvest (<20% of watershed area harvested) and (2) high timber harvest (>45% of watershed area harvested). A "Rapid Bed Profile" (REP) technique was developed to measure residual pool characteristics in each stream section. The REP technique is a survey method that requires only thalweg depths and the average reach gradient. The technique was effective for classifying pools since it is objective, independent of flow, accurate, and time-efficient. Residual pool size characteristics (e.g., volume) for the low timber harvest stream sections were positively correlated to a power function of drainage area. Stream sections with beaver dams, especially those with at least 10% of their reach length in beaver-caused pools, typically had larger residual pools. Pool size characteristics for high timber harvest stream sections were not different from low timber harvest stream sections. The average spacing between residual pools was positively correlated to a power function of drainage area for the low timber harvest stream sections (a negative correlation was found between the number of pools and drainage area). High timber harvest stream sections may be associated with an increased spacing and a decreased number of pools for larger watersheds (i.e., greater than 8 km²). However, the potential effects of previous large storms, changes in timber management practices, and/or the small number of streams surveyed precluded a definitive conclusion. The frequency of occurrence of pool forming processes (e.g., plunge, deflection) was correlated with average water surface slope for the low timber harvest stream sections. The percentage of plunge and impoundment processes increased as water surface slope increased while the percentage of deflection and underflow processes decreased. Two high timber harvest streams had a higher percentage of plunge pools than expected based on the relationships established for the low timber harvest streams. The frequency of occurrence of wood and boulder pool forming elements was correlated with an index of stream power (drainage area times average water slope) for the low timber harvest stream sections. As the stream power index increased, the relative frequency of wood-formed pools decreased while boulder-formed pools increased. Wood and boulder combined, generally, made up 80% of the pool forming elements. The frequency of occurrence of pool forming elements was not different between low and high timber harvest stream sections. Close

• 11. [Article] Statistical summaries of streamflow data in Oregon : Volume 2 Western Oregon

  Statistical summaries of streamflow data at 212 stream-gaging sites are presented in this report to aid in appraising the hydrology of river basins in Western Oregon. Records for 21 gaging stations were ...

  Citation × Citation Citation Abstract Copy Title: Statistical summaries of streamflow data in Oregon : Volume 2 Western Oregon Author: Oregon. Water Resources Dept., Miller, Suzanne J., Friday, John, Geological Survey (U.S.) Statistical summaries of streamflow data at 212 stream-gaging sites are presented in this report to aid in appraising the hydrology of river basins in Western Oregon. Records for 21 gaging stations were compiled into separate periods owing to changes in regulation during the period of data collection. The periods before and after regulation are presented for comparison. Title: Statistical summaries of streamflow data in Oregon : Volume 2 Western Oregon Author: Oregon. Water Resources Dept., Miller, Suzanne J., Friday, John, Geological Survey (U.S.) Statistical summaries of streamflow data at 212 stream-gaging sites are presented in this report to aid in appraising the hydrology of river basins in Western Oregon. Records for 21 gaging stations were compiled into separate periods owing to changes in regulation during the period of data collection. The periods before and after regulation are presented for comparison. Close

• 12. [Article] Patterns in stream geomorphology and implications for hyporheic exchange flow

  Longitudinal water surface profiles from high-gradient mountain streams provide useful indicators of the relative potential for hyporheic exchange flow in stream reaches with varying morphology. The spacing ...

  Citation × Citation Citation Abstract Copy Title: Patterns in stream geomorphology and implications for hyporheic exchange flow Author: Anderson, Justin K. Longitudinal water surface profiles from high-gradient mountain streams provide useful indicators of the relative potential for hyporheic exchange flow in stream reaches with varying morphology. The spacing between slope breaks in step-pool and pool-riffle streams provides a geomorphic scaling metric that indicates how the length of average hyporheic flow paths change throughout the river continuum. Twelve stream reaches were randomly selected and surveyed in the Lookout Creek basin at the H.J. Andrews Experimental Forest in the western Cascades Mountains of Oregon. Stream reach morphology was examined for patterns that are expressed over a continuum ranging from headwater to mid-order streams that can be predicted from easily measured drainage basin characteristics. Simple and multiple linear regression models were used to predict changes in lateral complexity in stream reaches, and to predict how the general shape of the water surface profile changes as drainage basin area increases from 0.6 km² to 62.3 km². Patterns in the lateral complexity of stream reaches were associated with the degree of channel confinement in valley segments, and longitudinal patterns in bed configuration were strongly associated with the position of a stream reach within the river continuum. Stream reach longitudinal profiles were evaluated to determine how patterns in slope breaks change throughout the portion of the river continuum represented by the study area. Channel units were defined according to slope categories for flat water, steep water, and step units (FLATs, STEEPs and STEPs). A set of regression models was used to predict how slope break spacing and the general shape of the water surface profile change as drainage basin area increases from 0.6 km² to 62.3 km². Output from these regression equations was tested against independent field data to evaluate model performance. The models generally performed well. Longitudinal transects of piezometers were installed along the thalweg of a second order, and a third order stream reach. Longitudinal profiles in the piezometer transects were surveyed, and piezometers were used to measure hydraulic head in stream beds. Data were used to test a theoretical model that predicts downwelling where stream profiles are convex, and upwelling where stream profiles are concave. Overall, the shape of the water surface profile explained 38% of the variation in the distribution of hydraulic pressure head in the streambed. Results demonstrated the usefulness of quantifying the magnitude of concavities and convexities in stream profiles. A metric for expressing the average water surface concavity (AWSC) is proposed. I demonstrated that this metric could be useful for comparing the potential for hyporheic exchange in stream reaches with varying degrees of stream profile roughness. Results showed a decreasing trend in AWSC as drainage basin area increased. Upwelling and downwelling zones were identified in piezometer transects, and their longitudinal lengths were measured. The lengths of downwelling zones were compared to the spacing between slope breaks in the water surface profile. Average lengths of downwelling zones and FLAT channel slope units increased with increasing basin area at a similar rate, indicating that slope break spacing was a useful indicator for average downwelling zone length. My results demonstrate that patterns in stream morphology are useful for predicting patterns in hyporheic exchange flow throughout the river continuum. I suggest that the potential for gravity driven exchange flow decreases along the river continuum as AWSC decreases. I also suggest that the frequency of hydrologic exchange between the stream and the hyporheic zone decreases, and that the average length of hyporheic flow paths increase, across the river continuum. Title: Patterns in stream geomorphology and implications for hyporheic exchange flow Author: Anderson, Justin K. Longitudinal water surface profiles from high-gradient mountain streams provide useful indicators of the relative potential for hyporheic exchange flow in stream reaches with varying morphology. The spacing between slope breaks in step-pool and pool-riffle streams provides a geomorphic scaling metric that indicates how the length of average hyporheic flow paths change throughout the river continuum. Twelve stream reaches were randomly selected and surveyed in the Lookout Creek basin at the H.J. Andrews Experimental Forest in the western Cascades Mountains of Oregon. Stream reach morphology was examined for patterns that are expressed over a continuum ranging from headwater to mid-order streams that can be predicted from easily measured drainage basin characteristics. Simple and multiple linear regression models were used to predict changes in lateral complexity in stream reaches, and to predict how the general shape of the water surface profile changes as drainage basin area increases from 0.6 km² to 62.3 km². Patterns in the lateral complexity of stream reaches were associated with the degree of channel confinement in valley segments, and longitudinal patterns in bed configuration were strongly associated with the position of a stream reach within the river continuum. Stream reach longitudinal profiles were evaluated to determine how patterns in slope breaks change throughout the portion of the river continuum represented by the study area. Channel units were defined according to slope categories for flat water, steep water, and step units (FLATs, STEEPs and STEPs). A set of regression models was used to predict how slope break spacing and the general shape of the water surface profile change as drainage basin area increases from 0.6 km² to 62.3 km². Output from these regression equations was tested against independent field data to evaluate model performance. The models generally performed well. Longitudinal transects of piezometers were installed along the thalweg of a second order, and a third order stream reach. Longitudinal profiles in the piezometer transects were surveyed, and piezometers were used to measure hydraulic head in stream beds. Data were used to test a theoretical model that predicts downwelling where stream profiles are convex, and upwelling where stream profiles are concave. Overall, the shape of the water surface profile explained 38% of the variation in the distribution of hydraulic pressure head in the streambed. Results demonstrated the usefulness of quantifying the magnitude of concavities and convexities in stream profiles. A metric for expressing the average water surface concavity (AWSC) is proposed. I demonstrated that this metric could be useful for comparing the potential for hyporheic exchange in stream reaches with varying degrees of stream profile roughness. Results showed a decreasing trend in AWSC as drainage basin area increased. Upwelling and downwelling zones were identified in piezometer transects, and their longitudinal lengths were measured. The lengths of downwelling zones were compared to the spacing between slope breaks in the water surface profile. Average lengths of downwelling zones and FLAT channel slope units increased with increasing basin area at a similar rate, indicating that slope break spacing was a useful indicator for average downwelling zone length. My results demonstrate that patterns in stream morphology are useful for predicting patterns in hyporheic exchange flow throughout the river continuum. I suggest that the potential for gravity driven exchange flow decreases along the river continuum as AWSC decreases. I also suggest that the frequency of hydrologic exchange between the stream and the hyporheic zone decreases, and that the average length of hyporheic flow paths increase, across the river continuum. Close

• 13. [Article] Analysis of streamflow variability in Oregon for regional water quality monitoring programs

  Streamflow variability can provide valuable information for nonpoint source pollution monitoring program planning. The research papers presented in this thesis examine selected properties of streamflow ...

  Citation × Citation Citation Abstract Copy Title: Analysis of streamflow variability in Oregon for regional water quality monitoring programs Author: Saligoe-Simmel, Julia L. Streamflow variability can provide valuable information for nonpoint source pollution monitoring program planning. The research papers presented in this thesis examine selected properties of streamflow variability in Oregon to advance its application in regional planning of water quality monitoring programs. The products of this research depict Oregon streams by their relative streamflow variability and evaluate factors that may influence that variability. The three manuscripts examine the application of streamflow variability in the context of regional strategic planning by addressing three related questions: 1.) What is the relationship in Oregon between streamflow variability and watershed size, which is often described as a proxy for streamflow variability?, 2.) What geographic factors in Oregon influence streamflow variability, and are regionalscale factors adequate to efficiently predict streamflow variability on ungaged streams?, and 3.) How is streamflow variability in Oregon affected by seasonal climatic variation? Examination of these questions regarding the behavior of streamflow variability of river systems in Oregon is used to assist in the design of regional and local water quality monitoring programs. Data are from historical records of established US Geological Survey gaging stations. Simple linear regression depicts the relationship of streamflow variability to basin size on a statewide basis and stratified by ecoregions. The results indicate that basin area is not an appropriate indicator of streamflow variability. Multiple regression is used to develop regional models of streamflow variability. Three models are developed for natural flow streams and streams with upstream diversions. Regional and watershed scale variables are evaluated for their potential contributions to the models. Watershed scale variables do not increase the predictive capacity of the models; therefore, the regional scale is appropriate for efficiently modeling streamflow variability. Seasonal investigation of streamflow variability in Oregon develops its application for seasonal monitoring programs. Spatial and temporal analysis reveal a weak relationship between annual and monthly streamflow variability, indicating potential for refined application of the variability index. Streamflow variability is an accessible tool for developing water quality monitoring programs. The regional scale distribution of streamflow variability in Oregon demonstrates the ease at which streamflow variability may be estimated on ungaged streams. Title: Analysis of streamflow variability in Oregon for regional water quality monitoring programs Author: Saligoe-Simmel, Julia L. Streamflow variability can provide valuable information for nonpoint source pollution monitoring program planning. The research papers presented in this thesis examine selected properties of streamflow variability in Oregon to advance its application in regional planning of water quality monitoring programs. The products of this research depict Oregon streams by their relative streamflow variability and evaluate factors that may influence that variability. The three manuscripts examine the application of streamflow variability in the context of regional strategic planning by addressing three related questions: 1.) What is the relationship in Oregon between streamflow variability and watershed size, which is often described as a proxy for streamflow variability?, 2.) What geographic factors in Oregon influence streamflow variability, and are regionalscale factors adequate to efficiently predict streamflow variability on ungaged streams?, and 3.) How is streamflow variability in Oregon affected by seasonal climatic variation? Examination of these questions regarding the behavior of streamflow variability of river systems in Oregon is used to assist in the design of regional and local water quality monitoring programs. Data are from historical records of established US Geological Survey gaging stations. Simple linear regression depicts the relationship of streamflow variability to basin size on a statewide basis and stratified by ecoregions. The results indicate that basin area is not an appropriate indicator of streamflow variability. Multiple regression is used to develop regional models of streamflow variability. Three models are developed for natural flow streams and streams with upstream diversions. Regional and watershed scale variables are evaluated for their potential contributions to the models. Watershed scale variables do not increase the predictive capacity of the models; therefore, the regional scale is appropriate for efficiently modeling streamflow variability. Seasonal investigation of streamflow variability in Oregon develops its application for seasonal monitoring programs. Spatial and temporal analysis reveal a weak relationship between annual and monthly streamflow variability, indicating potential for refined application of the variability index. Streamflow variability is an accessible tool for developing water quality monitoring programs. The regional scale distribution of streamflow variability in Oregon demonstrates the ease at which streamflow variability may be estimated on ungaged streams. Close

• 14. [Article] An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability

  Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel ...

  Citation × Citation Citation Abstract Copy Title: An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability Author: Morét, Stephanie L. Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. Title: An assessment of a Stream Reach Inventory and Channel Stability Evaluation : predicting and detecting flood-induced change in channel stability Author: Morét, Stephanie L. Pre-flood (1995), and post-flood (1996) channel stability surveys were conducted on 22 reaches along Oak Creek, Benton County, Oregon in an effort to note if the flood of February 1996 altered the channel and if the channel stability survey that was being used accurately predicted the channels resistance to change resulting from a flood. The channel stability survey that was used was the method described in the 'Channel Stability Evaluation and Stream Reach Inventory' designed by the USDA Forest Service, Northern Region, in Colorado (Pfankuch, 1978). This was a non-parametric study, based on an opportunity to reoccupy survey locations from a previous study. A model was proposed to describe the 1995 ratings as predictions for change should a flood event occur. This predicted change was compared to the actual change that occurred as a result of the 1996 flood in order to test the surveys ability to accurately predict change. Changes in the survey totals, the 15 channel stability indicator items that compose the survey, and the sediment distribution were evaluated within and between years at the reach, station and stream scale. An increase in the percentage of fine gravel occurred at all scales when post-flood and pre-flood sediment distribution was compared. Except for an increase in fine gravel, the stream remained similar to its pre-flood state. In 1995, the stream's channel stability was rated as 'fair', indicating that a moderate amount of change should take place if a flood occurred. The 1995 predictions for change did not match the actual change observed after the February 1996 flood at the three scales when defined by the survey totals. When independently evaluating the fifteen individual channel stability indicator items, a considerable amount of change was detected at the reach level. Although change occurred in the indicator items at each reach, the stream average for each of the independent indicator items was similar between the two years. This may indicate that, although change occurred at the reach level, the stream maintained its physical diversity after the flood. The survey method was unable to accurately predict changes to Oak Creek incurred by the February 1996 flood when viewed at the entire stream level, yet it may be more applicable at the reach level when viewing specific changes to channel stability indicator items. In general, the Stream Reach Inventory and Channel Stability Evaluation is designed for observational efficiency but does not have sufficient scientific basis or measurement precision to accurately predict the extent or type of channel change. Close

• 15. [Article] Summertime water temperature trends in Steamboat Creek Basin, Umpqua National Forest

  The Steamboat Creek basin drains 227 mi² (588 km²) of steep forested terrain into the North Umpqua River of Southwest Oregon, 39 mi (63 km) northeast of Roseburg. Summer base flows for Steamboat Creek ...

  Citation × Citation Citation Abstract Copy Title: Summertime water temperature trends in Steamboat Creek Basin, Umpqua National Forest Author: Holaday, Steven A. The Steamboat Creek basin drains 227 mi² (588 km²) of steep forested terrain into the North Umpqua River of Southwest Oregon, 39 mi (63 km) northeast of Roseburg. Summer base flows for Steamboat Creek average 83 cfs (2.35 m³/sec). Steamboat Creek and its tributaries are considered important to the production of summer-run steelhead; the basin has been closed to angling since 1932. Harvesting has occurred in every subdrainage of the Steamboat Creek basin. Trees were routinely removed from riparian areas when harvesting in the basin began in 1955. Since the mid-1970s to early-1980s, however, buffer strips were left adjacent to streams. In addition, the floods of 1964-65 caused significant damage to riparian vegetation in the basin. This study was undertaken to: (1) determine long-term trends over the period 1969-90 of summertime water temperatures in the mainstem of Steamboat Creek, selected tributaries, and in Boulder Creek, an unharvested control stream in an adjacent watershed and (2) evaluate spacial patterns of maximum water temperatures in the Steamboat Creek basin during the summer of 1990. Significant (P≤0.10) trends of decreasing maximum daily summertime stream temperatures on Steamboat Creek and tributaries occurred from 1969-90. In contrast, an unharvested control stream showed a small, but nonsignificant, increasing trend in stream temperatures. The largest decrease in maximum stream temperatures (7 to 11°F, 3.9 to 6.1°C) occurred on small streams with summer base flows less than 6 cfs (0.17 m³/sec). These streams also had the highest proportion of stream length adjacent to harvesting activities before 1974. The smallest decrease in maximum stream temperatures (0 to 3°F, 0 to 1.7°C) occurred on streams with little or no history of timber harvest activity along riparian areas, or at locations where summer base flows were greater than 15 cfs (0.42 m³/sec). Since no trends in either air temperature or streamflow were apparent over the 1969-90 period, regrowth of riparian vegetation that was previously removed by flooding, debris torrents, or streamside harvesting, appears to be the major cause of trends in decreasing maximum summer stream temperature. Regrowth of riparian vegetation provides shade over small streams, decreasing energy input to the stream from solar radiation. Maximum daily stream temperatures in lower Steamboat Creek did not change significantly during the 1969-90 study period and stream temperature data in 1960 indicates that maximum stream temperatures in lower Steamboat Creek have historically been high. Any cooling effects by groundwater or tributaries are largely negated by the large volume of water in the main channel. Also, the large stream width renders riparian vegetation relatively ineffective in protecting the stream from solar radiation. Minimum stream temperatures decreased during the 1969-90 study period for all of the long-term stations in the Steamboat Creek basin while the control stream showed a slight increasing trend. Similarly, diurnal stream temperature fluctuations decreased for several tributaries. Title: Summertime water temperature trends in Steamboat Creek Basin, Umpqua National Forest Author: Holaday, Steven A. The Steamboat Creek basin drains 227 mi² (588 km²) of steep forested terrain into the North Umpqua River of Southwest Oregon, 39 mi (63 km) northeast of Roseburg. Summer base flows for Steamboat Creek average 83 cfs (2.35 m³/sec). Steamboat Creek and its tributaries are considered important to the production of summer-run steelhead; the basin has been closed to angling since 1932. Harvesting has occurred in every subdrainage of the Steamboat Creek basin. Trees were routinely removed from riparian areas when harvesting in the basin began in 1955. Since the mid-1970s to early-1980s, however, buffer strips were left adjacent to streams. In addition, the floods of 1964-65 caused significant damage to riparian vegetation in the basin. This study was undertaken to: (1) determine long-term trends over the period 1969-90 of summertime water temperatures in the mainstem of Steamboat Creek, selected tributaries, and in Boulder Creek, an unharvested control stream in an adjacent watershed and (2) evaluate spacial patterns of maximum water temperatures in the Steamboat Creek basin during the summer of 1990. Significant (P≤0.10) trends of decreasing maximum daily summertime stream temperatures on Steamboat Creek and tributaries occurred from 1969-90. In contrast, an unharvested control stream showed a small, but nonsignificant, increasing trend in stream temperatures. The largest decrease in maximum stream temperatures (7 to 11°F, 3.9 to 6.1°C) occurred on small streams with summer base flows less than 6 cfs (0.17 m³/sec). These streams also had the highest proportion of stream length adjacent to harvesting activities before 1974. The smallest decrease in maximum stream temperatures (0 to 3°F, 0 to 1.7°C) occurred on streams with little or no history of timber harvest activity along riparian areas, or at locations where summer base flows were greater than 15 cfs (0.42 m³/sec). Since no trends in either air temperature or streamflow were apparent over the 1969-90 period, regrowth of riparian vegetation that was previously removed by flooding, debris torrents, or streamside harvesting, appears to be the major cause of trends in decreasing maximum summer stream temperature. Regrowth of riparian vegetation provides shade over small streams, decreasing energy input to the stream from solar radiation. Maximum daily stream temperatures in lower Steamboat Creek did not change significantly during the 1969-90 study period and stream temperature data in 1960 indicates that maximum stream temperatures in lower Steamboat Creek have historically been high. Any cooling effects by groundwater or tributaries are largely negated by the large volume of water in the main channel. Also, the large stream width renders riparian vegetation relatively ineffective in protecting the stream from solar radiation. Minimum stream temperatures decreased during the 1969-90 study period for all of the long-term stations in the Steamboat Creek basin while the control stream showed a slight increasing trend. Similarly, diurnal stream temperature fluctuations decreased for several tributaries. Close

• 16. [Article] Effects of harvest and roads on in-stream wood abundance in the Blue River Basin, western Cascades, Oregon

  Despite many studies of large wood in streams, few landscape scale studies have been conducted. Large-scale studies can reveal how the history of forest harvest and road building has influenced wood patterns ...

  Citation × Citation Citation Abstract Copy Title: Effects of harvest and roads on in-stream wood abundance in the Blue River Basin, western Cascades, Oregon Author: Czarnomski, Nicole M. Despite many studies of large wood in streams, few landscape scale studies have been conducted. Large-scale studies can reveal how the history of forest harvest and road building has influenced wood patterns in streams of the Pacific Northwest. This study examined the relationships between wood in streams, timber harvest, and road building at large (>50 km² ) spatial and long (>25 year) temporal scales, based on longitudinal surveys of 25.2 km of stream length in five sub-basins of the Blue River Basin, Cascade Range, Oregon. In-stream wood was surveyed in six sampling sites, ranging from 1.6 km to 14.1 km in length along 2nd to 5th -order channels in public forests. Wood volumes, numbers of pieces of large wood, numbers of accumulations and timing of emplacement were determined at 50-m intervals. Wood volumes and numbers of pieces were expressed per unit of channel area in order to account for variations in channel width. Wood volumes and piece numbers were related to spatial data on harvest and road building using GIS. Analysis of variance (using SAS) tested how wood volumes and piece numbers were related to the presence of a harvest or road unit within 40 m of the stream, sampling site, timing of harvest, distance harvest was from the channel, and effects of natural processes. P-values for pairwise comparisons were adjusted using a Bonfenoni procedure. Distributed patch clearcutting and road construction were concentrated in the 1950's and 1960's in the Lookout Creek basin and 1960's to the 1980's in the Upper Blue River basin. A total of 66% (Cook Creek), 55% (Mack Creek), 53% (Lower Lookout), 37% (McRae Creek and Upper Lookout), and 7% (Quentin Creek) of stream length had harvests and/or roads within 40 m of the stream. Approximately 80% of the wood volume and 85% of the number of large pieces occurred in accumulations. Wood volumes were lower in 5th-order compared to 3rd -order streams. Lower Lookout (the only 5th-order channel) had significantly lower wood volumes (109 m³/ha) than all other locations (200-378 m³/ha, p<O.O5) and significantly lower numbers of large pieces (23 large pieces/ha) compared to all other locations (39 vs. 64 large pieces/ha, p<O.008). All other locations had fairly similar wood volumes and numbers of large pieces For all study sites combined, 50-m stream segments without harvests or roads had significantly higher volume (356 m³/ha) and number of large pieces (57 pieces/ha), than stream segments with harvests or roads within 40 m (80 to 157 m³/ha, p<O.O3; 19 to 39 pieces/ha, p<O.O4). Stream segments without harvests or roads (32 pieces/ha) also had significantly higher number of accumulations compared to stream segments with roads (16 pieces/ha, p<O.004), or compared to stream segments with harvest on one side and roads (16 pieces/ha, p<O.004). Distance a harvest was from the stream and timing of harvest did not appear to affect wood volume or number of large pieces. Harvests and roads were associated with decreases in wood abundance 50 m upstream and 50 m downstream of harvest units and road crossings. The 50-m stream segments immediately upstream (171.8 m³/ha) and downstream (191.6 m³/ha) of a section of stream with harvest and roads had significantly lower volume than the 50-m stream segments without harvest or roads (427.7 m³/ha, p<O. 1). Natural processes such as floods, windthrow, near-stream toppling, and debris flows from the last 50 years had not obscured the effects of harvest and roads on wood volume and number of pieces in stream channels of Lookout Creek and Blue River. The legacy of harvest and road activities was still apparent in in-stream wood patterns up to 50 years later in this site, which consisted of old-growth forest subjected to dispersed patch clearcutting, road construction, and salvage logging conducted in the 1950's to the 1980s. However, harvest, road, and salvage practices on public lands have changed since that period. Therefore, these results should be extrapolated to other sites only with careful consideration of site history. Title: Effects of harvest and roads on in-stream wood abundance in the Blue River Basin, western Cascades, Oregon Author: Czarnomski, Nicole M. Despite many studies of large wood in streams, few landscape scale studies have been conducted. Large-scale studies can reveal how the history of forest harvest and road building has influenced wood patterns in streams of the Pacific Northwest. This study examined the relationships between wood in streams, timber harvest, and road building at large (>50 km² ) spatial and long (>25 year) temporal scales, based on longitudinal surveys of 25.2 km of stream length in five sub-basins of the Blue River Basin, Cascade Range, Oregon. In-stream wood was surveyed in six sampling sites, ranging from 1.6 km to 14.1 km in length along 2nd to 5th -order channels in public forests. Wood volumes, numbers of pieces of large wood, numbers of accumulations and timing of emplacement were determined at 50-m intervals. Wood volumes and numbers of pieces were expressed per unit of channel area in order to account for variations in channel width. Wood volumes and piece numbers were related to spatial data on harvest and road building using GIS. Analysis of variance (using SAS) tested how wood volumes and piece numbers were related to the presence of a harvest or road unit within 40 m of the stream, sampling site, timing of harvest, distance harvest was from the channel, and effects of natural processes. P-values for pairwise comparisons were adjusted using a Bonfenoni procedure. Distributed patch clearcutting and road construction were concentrated in the 1950's and 1960's in the Lookout Creek basin and 1960's to the 1980's in the Upper Blue River basin. A total of 66% (Cook Creek), 55% (Mack Creek), 53% (Lower Lookout), 37% (McRae Creek and Upper Lookout), and 7% (Quentin Creek) of stream length had harvests and/or roads within 40 m of the stream. Approximately 80% of the wood volume and 85% of the number of large pieces occurred in accumulations. Wood volumes were lower in 5th-order compared to 3rd -order streams. Lower Lookout (the only 5th-order channel) had significantly lower wood volumes (109 m³/ha) than all other locations (200-378 m³/ha, p<O.O5) and significantly lower numbers of large pieces (23 large pieces/ha) compared to all other locations (39 vs. 64 large pieces/ha, p<O.008). All other locations had fairly similar wood volumes and numbers of large pieces For all study sites combined, 50-m stream segments without harvests or roads had significantly higher volume (356 m³/ha) and number of large pieces (57 pieces/ha), than stream segments with harvests or roads within 40 m (80 to 157 m³/ha, p<O.O3; 19 to 39 pieces/ha, p<O.O4). Stream segments without harvests or roads (32 pieces/ha) also had significantly higher number of accumulations compared to stream segments with roads (16 pieces/ha, p<O.004), or compared to stream segments with harvest on one side and roads (16 pieces/ha, p<O.004). Distance a harvest was from the stream and timing of harvest did not appear to affect wood volume or number of large pieces. Harvests and roads were associated with decreases in wood abundance 50 m upstream and 50 m downstream of harvest units and road crossings. The 50-m stream segments immediately upstream (171.8 m³/ha) and downstream (191.6 m³/ha) of a section of stream with harvest and roads had significantly lower volume than the 50-m stream segments without harvest or roads (427.7 m³/ha, p<O. 1). Natural processes such as floods, windthrow, near-stream toppling, and debris flows from the last 50 years had not obscured the effects of harvest and roads on wood volume and number of pieces in stream channels of Lookout Creek and Blue River. The legacy of harvest and road activities was still apparent in in-stream wood patterns up to 50 years later in this site, which consisted of old-growth forest subjected to dispersed patch clearcutting, road construction, and salvage logging conducted in the 1950's to the 1980s. However, harvest, road, and salvage practices on public lands have changed since that period. Therefore, these results should be extrapolated to other sites only with careful consideration of site history. Close

• 17. [Article] Statistical summaries of streamflow data in Oregon : Volume 2, annual low and high flow, and instantaneous peak flow

  Statistical summaries of streamfiow data at 358 stream-gaging sites are presented to aid in appraising the hydrology of river basins in Oregon. Records for 36 stream-gaging stations were compiled into ...

  Citation × Citation Citation Abstract Copy Title: Statistical summaries of streamflow data in Oregon : Volume 2, annual low and high flow, and instantaneous peak flow Author: Oregon. Water Resources Dept., Wellman, Roy E, Moffatt, R. L., Gordon, Janice M. Statistical summaries of streamfiow data at 358 stream-gaging sites are presented to aid in appraising the hydrology of river basins in Oregon. Records for 36 stream-gaging stations were compiled into separate periods because of changes in streamflow regulation during the period of data collection. Statistical summaries for the periods before and after regulation are presented for comparison. Title: Statistical summaries of streamflow data in Oregon : Volume 2, annual low and high flow, and instantaneous peak flow Author: Oregon. Water Resources Dept., Wellman, Roy E, Moffatt, R. L., Gordon, Janice M. Statistical summaries of streamfiow data at 358 stream-gaging sites are presented to aid in appraising the hydrology of river basins in Oregon. Records for 36 stream-gaging stations were compiled into separate periods because of changes in streamflow regulation during the period of data collection. Statistical summaries for the periods before and after regulation are presented for comparison. Close

• 18. [Article] Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967

  "Activities included spawning ground and physical stream surveys, sampling of shad and striped bass commercial fisheries, population estimates of juvenile coho in selected streams, evaluating releases ...

  Citation × Citation Citation Abstract Copy Title: Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967 Author: Oregon. Fish Commission. Research Division, Oregon. Pelagic Fisheries and Coastal Rivers Investigation "Activities included spawning ground and physical stream surveys, sampling of shad and striped bass commercial fisheries, population estimates of juvenile coho in selected streams, evaluating releases of adult and fry coho, studying coho in a lake environment, and investigations on the ecology of fall chinook in south coastal streams." (p.1) Title: Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967 Author: Oregon. Fish Commission. Research Division, Oregon. Pelagic Fisheries and Coastal Rivers Investigation "Activities included spawning ground and physical stream surveys, sampling of shad and striped bass commercial fisheries, population estimates of juvenile coho in selected streams, evaluating releases of adult and fry coho, studying coho in a lake environment, and investigations on the ecology of fall chinook in south coastal streams." (p.1) Close

• 19. [Article] Statistical summaries of streamflow data in Oregon : Volume 1 Eastern Oregon

  Statistical summaries of streamfiow data at 123 stream-gaging sites are presented in this report to aid in appraising the hydrology of river basins in Eastern Oregon. Records for 13 gaging stations were ...

  Citation × Citation Citation Abstract Copy Title: Statistical summaries of streamflow data in Oregon : Volume 1 Eastern Oregon Author: Oregon. Water Resources Dept., Miller, Suzanne J., Friday, John, Geological Survey (U.S.) Statistical summaries of streamfiow data at 123 stream-gaging sites are presented in this report to aid in appraising the hydrology of river basins in Eastern Oregon. Records for 13 gaging stations were compiled into separate periods owing to changes in regulation during the period of data collection. The periods before and after regulation are presented for comparison. A brief station description is given describing the physical and operational features for each gaging station. Following the station description are tables of monthly and annual flow statistics, flood frequency data, low-flow and high-flow frequency data, and flow-duration information. Title: Statistical summaries of streamflow data in Oregon : Volume 1 Eastern Oregon Author: Oregon. Water Resources Dept., Miller, Suzanne J., Friday, John, Geological Survey (U.S.) Statistical summaries of streamfiow data at 123 stream-gaging sites are presented in this report to aid in appraising the hydrology of river basins in Eastern Oregon. Records for 13 gaging stations were compiled into separate periods owing to changes in regulation during the period of data collection. The periods before and after regulation are presented for comparison. A brief station description is given describing the physical and operational features for each gaging station. Following the station description are tables of monthly and annual flow statistics, flood frequency data, low-flow and high-flow frequency data, and flow-duration information. Close

• 20. [Article] Breeding habitat of harlequin ducks in Prince William Sound, Alaska

  Breeding habitat of Harlequin ducks (Histrionicus histrionicus) was studied in eastern Prince William Sound, Alaska, during 1991 - 1993. Streams in Prince William Sound were surveyed for Harlequin ducks ...

  Citation × Citation Citation Abstract Copy Title: Breeding habitat of harlequin ducks in Prince William Sound, Alaska Author: Crowley, David W. Breeding habitat of Harlequin ducks (Histrionicus histrionicus) was studied in eastern Prince William Sound, Alaska, during 1991 - 1993. Streams in Prince William Sound were surveyed for Harlequin ducks and monitored with mist nets. Physical characteristics of 24 Harlequin breeding streams were compared to those of 24 streams not used for breeding using 2 sample, principal components and logistic regression analyses. Nests were located using radio-telemetry of marked females. Harlequin ducks resident in eastern Prince William Sound selected the largest anadromous salmon streams available for nesting. Volume discharge of breeding streams averaged 3.2 m³/s and was the most important factor in habitat variation between streams used and not used by breeding Harlequins. Expansive estuaries and intertidal deltas present at the outflow of large streams were important foraging and loafing areas of Harlequin ducks. Although nesting females generally avoided smaller salmon streams their intertidal estuaries were often used for foraging by females and molting males. The largest streams in Prince William Sound, glacially fed rivers, were not used by breeding Harlequins. Ten nest sites of Harlequin ducks in eastern Prince William Sound were located on southwest facing, steeply sloping banks of small, first order tributaries near timberline elevation. Nests were associated with woody debris and shrubs, in shallow depressions or cavities, and were beneath the canopy of old growth forest. Microhabitat produced by a southwest aspect, snow shadow provided by the forest canopy, and sloping stream bank may provide nesting sites earlier in the spring compared to surrounding areas. Title: Breeding habitat of harlequin ducks in Prince William Sound, Alaska Author: Crowley, David W. Breeding habitat of Harlequin ducks (Histrionicus histrionicus) was studied in eastern Prince William Sound, Alaska, during 1991 - 1993. Streams in Prince William Sound were surveyed for Harlequin ducks and monitored with mist nets. Physical characteristics of 24 Harlequin breeding streams were compared to those of 24 streams not used for breeding using 2 sample, principal components and logistic regression analyses. Nests were located using radio-telemetry of marked females. Harlequin ducks resident in eastern Prince William Sound selected the largest anadromous salmon streams available for nesting. Volume discharge of breeding streams averaged 3.2 m³/s and was the most important factor in habitat variation between streams used and not used by breeding Harlequins. Expansive estuaries and intertidal deltas present at the outflow of large streams were important foraging and loafing areas of Harlequin ducks. Although nesting females generally avoided smaller salmon streams their intertidal estuaries were often used for foraging by females and molting males. The largest streams in Prince William Sound, glacially fed rivers, were not used by breeding Harlequins. Ten nest sites of Harlequin ducks in eastern Prince William Sound were located on southwest facing, steeply sloping banks of small, first order tributaries near timberline elevation. Nests were associated with woody debris and shrubs, in shallow depressions or cavities, and were beneath the canopy of old growth forest. Microhabitat produced by a southwest aspect, snow shadow provided by the forest canopy, and sloping stream bank may provide nesting sites earlier in the spring compared to surrounding areas. Close