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• 81. [Article] ODFW Access and Habitat Areas and Projects in Oregon (2017)

  Abstract -- To show access areas supported by, or associated with, the Oregon Department of Fish and Wildlife (ODFW) Access and Habitat Program. For more details see: https://myodfw.com/articles/hunting-private-lands-access-habitat-program; ...

  Citation × Citation Citation Abstract Copy Title: ODFW Access and Habitat Areas and Projects in Oregon (2017) Abstract -- To show access areas supported by, or associated with, the Oregon Department of Fish and Wildlife (ODFW) Access and Habitat Program. For more details see: https://myodfw.com/articles/hunting-private-lands-access-habitat-program; http://www.dfw.state.or.us/lands/AH/; Title: ODFW Access and Habitat Areas and Projects in Oregon (2017) Abstract -- To show access areas supported by, or associated with, the Oregon Department of Fish and Wildlife (ODFW) Access and Habitat Program. For more details see: https://myodfw.com/articles/hunting-private-lands-access-habitat-program; http://www.dfw.state.or.us/lands/AH/; Close

• 82. [Article] An evaluation of the effectiveness of instream structures for steelhead trout rearing habitat in the Steamboat Creek basin.

  Several types of instream structures were evaluated for their potential to provide rearing habitat and to increase reach carrying capacity for steelhead trout (Salmo gairdneri). Evaluation was conducted ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of the effectiveness of instream structures for steelhead trout rearing habitat in the Steamboat Creek basin. Author: Fontaine, Barbara L. Several types of instream structures were evaluated for their potential to provide rearing habitat and to increase reach carrying capacity for steelhead trout (Salmo gairdneri). Evaluation was conducted in each season over the course of 1 year. Blast pools created in bedrock glides increased the carrying capacity of stream reaches during late summer. Three types of boulder and log structures in gravel-cobble glides did not significantly increase the late summer standing crop of juvenile steelhead. During summer, juvenile steelhead selected the habitat provided by the four types of structures over the untreated glide habitats. The instream structures were used by steelhead for feeding stations, resting areas, and hiding cover. Structures located near the thalweg held substantially more summering steelhead than structures in off-thalweg positions, regardless of structure design. In winter, seven structure designs were evaluated. The structures that were placed in zones of slow water (deep pools, margin backwater pools, and dam pools) provided the most effective winter habitat for juvenile steelhead. The structures with the largest concentrations of boulders and rubble generally held the highest winter densities. During the spring and fall months, habitat utilization was less predictable. Spring and fall were times of transition in which the utilization of habitat structures was probably influenced by changing water temperatures and hydraulic conditions. Prior to initiating habitat modification programs, habitat managers should conduct an on-site examination of the rearing strategy and seasonal habitat needs of the target species. A pre-work evaluation should be designed to gain an understanding of the most likely environmental factors that limit production. Without such preliminary information, and without a follow-up evaluation, managers cannot recognize their mistakes, innovate appropriate new techniques or determine if funds have been wisely spent. Title: An evaluation of the effectiveness of instream structures for steelhead trout rearing habitat in the Steamboat Creek basin. Author: Fontaine, Barbara L. Several types of instream structures were evaluated for their potential to provide rearing habitat and to increase reach carrying capacity for steelhead trout (Salmo gairdneri). Evaluation was conducted in each season over the course of 1 year. Blast pools created in bedrock glides increased the carrying capacity of stream reaches during late summer. Three types of boulder and log structures in gravel-cobble glides did not significantly increase the late summer standing crop of juvenile steelhead. During summer, juvenile steelhead selected the habitat provided by the four types of structures over the untreated glide habitats. The instream structures were used by steelhead for feeding stations, resting areas, and hiding cover. Structures located near the thalweg held substantially more summering steelhead than structures in off-thalweg positions, regardless of structure design. In winter, seven structure designs were evaluated. The structures that were placed in zones of slow water (deep pools, margin backwater pools, and dam pools) provided the most effective winter habitat for juvenile steelhead. The structures with the largest concentrations of boulders and rubble generally held the highest winter densities. During the spring and fall months, habitat utilization was less predictable. Spring and fall were times of transition in which the utilization of habitat structures was probably influenced by changing water temperatures and hydraulic conditions. Prior to initiating habitat modification programs, habitat managers should conduct an on-site examination of the rearing strategy and seasonal habitat needs of the target species. A pre-work evaluation should be designed to gain an understanding of the most likely environmental factors that limit production. Without such preliminary information, and without a follow-up evaluation, managers cannot recognize their mistakes, innovate appropriate new techniques or determine if funds have been wisely spent. Close

• 83. [Article] Association of Juvenile Salmon and Estuarine Fish with Intertidal Seagrass and Oyster Aquaculture Habitats in a Northeast Pacific Estuary

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the American Fisheries ...

  Citation × Citation Citation Abstract Copy Title: Association of Juvenile Salmon and Estuarine Fish with Intertidal Seagrass and Oyster Aquaculture Habitats in a Northeast Pacific Estuary Author: Dumbauld, Brett R., Bosley, Katelyn M., Hosack, Geoffrey R. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the American Fisheries Society and published by Taylor & Francis. It can be found at: http://www.tandfonline.com/toc/utaf20/current Title: Association of Juvenile Salmon and Estuarine Fish with Intertidal Seagrass and Oyster Aquaculture Habitats in a Northeast Pacific Estuary Author: Dumbauld, Brett R., Bosley, Katelyn M., Hosack, Geoffrey R. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the American Fisheries Society and published by Taylor & Francis. It can be found at: http://www.tandfonline.com/toc/utaf20/current Close

• 84. [Article] Sandy beach surf zones: An alternative nursery habitat for 0-age Chinook salmon

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/estuarine-coasta...

  Citation × Citation Citation Abstract Copy Title: Sandy beach surf zones: An alternative nursery habitat for 0-age Chinook salmon Author: Miller, J. A., Marin Jarrin, J. R. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/estuarine-coastal-and-shelf-science/. Title: Sandy beach surf zones: An alternative nursery habitat for 0-age Chinook salmon Author: Miller, J. A., Marin Jarrin, J. R. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/estuarine-coastal-and-shelf-science/. Close

• 85. [Article] A Bayesian approach to habitat suitability prediction

  For the west coast of North America, from northern California to southern Washington, a habitat suitability prediction framework was developed to support wave energy device siting. Concern that wave energy ...

  Citation × Citation Citation Abstract Copy Title: A Bayesian approach to habitat suitability prediction Author: Lockett, Daniel Edwin IV For the west coast of North America, from northern California to southern Washington, a habitat suitability prediction framework was developed to support wave energy device siting. Concern that wave energy devices may impact the seafloor and benthos has renewed research interest in the distribution of marine benthic invertebrates and factors influencing their distribution. A Bayesian belief network approach was employed for learning species-habitat associations for Rhabdus rectius, a tusk-shaped marine infaunal Mollusk. Environmental variables describing surficial geology and water depth were found to be most influential to the distribution of R. rectius. Water property variables, such as temperature and salinity, were less influential as distribution predictors. Species-habitat associations were used to predict habitat suitability probabilities for R. rectius, which were then mapped over an area of interest along the south-central Oregon coast. Habitat suitability prediction models tested well against data withheld for crossvalidation supporting our conclusion that Bayesian learning extracts useful information available in very small, incomplete data sets and identifies which variables drive habitat suitability for R. rectius. Additionally, Bayesian belief networks are easily updated with new information, quantitative or qualitative, which provides a flexible mechanism for multiple scenario analyses. The prediction framework presented here is a practical tool informing marine spatial planning assessment through visualization of habitat suitability. Title: A Bayesian approach to habitat suitability prediction Author: Lockett, Daniel Edwin IV For the west coast of North America, from northern California to southern Washington, a habitat suitability prediction framework was developed to support wave energy device siting. Concern that wave energy devices may impact the seafloor and benthos has renewed research interest in the distribution of marine benthic invertebrates and factors influencing their distribution. A Bayesian belief network approach was employed for learning species-habitat associations for Rhabdus rectius, a tusk-shaped marine infaunal Mollusk. Environmental variables describing surficial geology and water depth were found to be most influential to the distribution of R. rectius. Water property variables, such as temperature and salinity, were less influential as distribution predictors. Species-habitat associations were used to predict habitat suitability probabilities for R. rectius, which were then mapped over an area of interest along the south-central Oregon coast. Habitat suitability prediction models tested well against data withheld for crossvalidation supporting our conclusion that Bayesian learning extracts useful information available in very small, incomplete data sets and identifies which variables drive habitat suitability for R. rectius. Additionally, Bayesian belief networks are easily updated with new information, quantitative or qualitative, which provides a flexible mechanism for multiple scenario analyses. The prediction framework presented here is a practical tool informing marine spatial planning assessment through visualization of habitat suitability. Close

• 86. [Article] Habitat associations and determinants of refuge use in post-settlement lingcod (Ophiodon elongatus)

  Lingcod are an overexploited fish species in the Pacific Northwest and although there has been extensive study of the habitat requirements of adults, particularly during spawning, relatively little is ...

  Citation × Citation Citation Abstract Copy Title: Habitat associations and determinants of refuge use in post-settlement lingcod (Ophiodon elongatus) Author: Petrie, Megan E. Lingcod are an overexploited fish species in the Pacific Northwest and although there has been extensive study of the habitat requirements of adults, particularly during spawning, relatively little is known regarding the habitat requirements of post-settlement juveniles. Many juvenile fish use structural components of habitat to alleviate the risk of predation, as well as for foraging. Laboratory experiments and a field tagging study were performed in order to investigate habitat preference in juvenile lingcod, as well as factors that govern habitat use. Initial laboratory experiments demonstrated an affinity by juvenile lingcod for structure over bare sand habitats, whether the structure was rock, shell or seagrass. Body size, nutritional state, and light level were also found to be determinants of the extent to which juvenile lingcod use structural refuges. In the laboratory, older, larger individuals exhibited a higher propensity for structure use than did smaller juvenile fish. In fish of both body sizes, increasing hunger levels caused fish to emerge more readily from refuges than did those that were satiated. Die! patterns of ambient illumination were simulated in the laboratory, and refuge use decreased significantly in response to lower nocturnal light levels, a pattern that was not observed in the smaller size class. An acoustic tagging study conducted in Yaquina Bay, Oregon corroborated the basic habitat preferences seen in laboratory experiments. Juvenile lingcod showed a high degree of site fidelity, remaining in discreet areas of significant structural complexity, as revealed by underwater video of benthic habitat. The way in which an animal utilizes structural refuges adds or detracts from individual fitness, making this investigation into the habitat requirements of post-settlement lingcod an important step in understanding the life history and ecology of an important recreational and commercial species. Title: Habitat associations and determinants of refuge use in post-settlement lingcod (Ophiodon elongatus) Author: Petrie, Megan E. Lingcod are an overexploited fish species in the Pacific Northwest and although there has been extensive study of the habitat requirements of adults, particularly during spawning, relatively little is known regarding the habitat requirements of post-settlement juveniles. Many juvenile fish use structural components of habitat to alleviate the risk of predation, as well as for foraging. Laboratory experiments and a field tagging study were performed in order to investigate habitat preference in juvenile lingcod, as well as factors that govern habitat use. Initial laboratory experiments demonstrated an affinity by juvenile lingcod for structure over bare sand habitats, whether the structure was rock, shell or seagrass. Body size, nutritional state, and light level were also found to be determinants of the extent to which juvenile lingcod use structural refuges. In the laboratory, older, larger individuals exhibited a higher propensity for structure use than did smaller juvenile fish. In fish of both body sizes, increasing hunger levels caused fish to emerge more readily from refuges than did those that were satiated. Die! patterns of ambient illumination were simulated in the laboratory, and refuge use decreased significantly in response to lower nocturnal light levels, a pattern that was not observed in the smaller size class. An acoustic tagging study conducted in Yaquina Bay, Oregon corroborated the basic habitat preferences seen in laboratory experiments. Juvenile lingcod showed a high degree of site fidelity, remaining in discreet areas of significant structural complexity, as revealed by underwater video of benthic habitat. The way in which an animal utilizes structural refuges adds or detracts from individual fitness, making this investigation into the habitat requirements of post-settlement lingcod an important step in understanding the life history and ecology of an important recreational and commercial species. Close

• 87. [Article] Seasonal distribution and habitat selection by the redside shiner, Richardsonius balteatus, in a small Oregon stream

  Seasonal habitat availability, utilization, and selection by young of the year (< 25 mm) and adult (>25 mm) redside shiner, Richardsonius balteatus, were studied for 1 year in sections of Greasy Creek, ...

  Citation × Citation Citation Abstract Copy Title: Seasonal distribution and habitat selection by the redside shiner, Richardsonius balteatus, in a small Oregon stream Author: Rodnick, Kenneth J. Seasonal habitat availability, utilization, and selection by young of the year (< 25 mm) and adult (>25 mm) redside shiner, Richardsonius balteatus, were studied for 1 year in sections of Greasy Creek, Benton County, Oregon. Intensive stream mapping procedures and snorkling observations provided most of the quantitative measures for habitat availability and utilization respectively. A multivariate discriminant analysis and classification suggested spatial segregation of young of the year and adult redside shiners along gradients of water velocity and depth of the water column. Throughout the year, young redside shiners occupied shallower water than adults and utilized areas with lower mean water velocities. Associated with increased winter stream flows and lowered water temperatures (< 10° C), redside shiners were inactive and found in habitats offering the most cover and refuge from current. Overwintering areas populated by redside shiners included undercut banks, root wads, bank failures, fallen trees, and backwaters. During the transitional period between winter and summer, adult redside shiners shifted from overwintering habitats to the faster water of the main channel. Activities related to spawning and aggressive defense of space accompanied this shift. Young redside shiners continued to utilize protected margins. A multivariate discriminant analysis and classification comparing available and utilized stream habitats provided indices of habitat selection. Both young of the year and adult redside shiners were relatively selective in the stream habitats they utilized. The importance of four physical components (depth, current velocity, substrate composition, and cover forms) varied seasonally and with the life stage considered. Similar patterns of habitat utilization for redside shiners were observed in four larger streams and rivers. The availability of large, deep pools was important, new habitat for both young and adult redside shiners during periods of reduced stream flow in larger streams and rivers. Title: Seasonal distribution and habitat selection by the redside shiner, Richardsonius balteatus, in a small Oregon stream Author: Rodnick, Kenneth J. Seasonal habitat availability, utilization, and selection by young of the year (< 25 mm) and adult (>25 mm) redside shiner, Richardsonius balteatus, were studied for 1 year in sections of Greasy Creek, Benton County, Oregon. Intensive stream mapping procedures and snorkling observations provided most of the quantitative measures for habitat availability and utilization respectively. A multivariate discriminant analysis and classification suggested spatial segregation of young of the year and adult redside shiners along gradients of water velocity and depth of the water column. Throughout the year, young redside shiners occupied shallower water than adults and utilized areas with lower mean water velocities. Associated with increased winter stream flows and lowered water temperatures (< 10° C), redside shiners were inactive and found in habitats offering the most cover and refuge from current. Overwintering areas populated by redside shiners included undercut banks, root wads, bank failures, fallen trees, and backwaters. During the transitional period between winter and summer, adult redside shiners shifted from overwintering habitats to the faster water of the main channel. Activities related to spawning and aggressive defense of space accompanied this shift. Young redside shiners continued to utilize protected margins. A multivariate discriminant analysis and classification comparing available and utilized stream habitats provided indices of habitat selection. Both young of the year and adult redside shiners were relatively selective in the stream habitats they utilized. The importance of four physical components (depth, current velocity, substrate composition, and cover forms) varied seasonally and with the life stage considered. Similar patterns of habitat utilization for redside shiners were observed in four larger streams and rivers. The availability of large, deep pools was important, new habitat for both young and adult redside shiners during periods of reduced stream flow in larger streams and rivers. Close

• 88. [Article] Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon

  I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande ...

  Citation × Citation Citation Abstract Copy Title: Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon Author: Price, David M. I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units, and microhabitats, and to assess chinook salmon fidelity to those habitats using radio-telemetry. The analyses showed that habitat quality and availability in the seven study streams varied. Each stream posed different physical constraints on adult chinook salmon habitat; this was reflected by the differential use of habitat by salmon among streams. Salmon elected pools almost exclusively in the John Day Basin, whereas pools and riffles were elected in near equal proportion in the Grande Ronde and Inmaha basins. Within streams, use was similar between years. Almost all salmon were observed in association with cover, but the type of cover largely reflected availablity. Chinook salmon elected the deepest depths within channel units (microhabitat scale), but not necessarily the deepest channel units among streams (channel unit scale). Chinook salmon did not elect cooler stream temperatures within channel units in any study stream, except the Middle Fork John Day River. Radio-tagged chinook showed a high fidelity to habitats, except when stream temperatures approached lethal limits. Due to stream specific differences in habitat availability and use, multiscale habitat assessments for individual streams are recommended to increase the success of watershed restoration activities. Title: Multiscale habitat electivity and movement patterns by adult spring chinook salmon in seven river basins of northeast Oregon Author: Price, David M. I examined habitat electivity and movement patterns of adult spring chinook salmon at microhabitat and channel unit spatial scales, and seasonal to annual temporal scales in seven streams in the Grande Ronde, John Day, and Imnaha basins. The objective was to compare habitat use and availability among streams, channel units, and microhabitats, and to assess chinook salmon fidelity to those habitats using radio-telemetry. The analyses showed that habitat quality and availability in the seven study streams varied. Each stream posed different physical constraints on adult chinook salmon habitat; this was reflected by the differential use of habitat by salmon among streams. Salmon elected pools almost exclusively in the John Day Basin, whereas pools and riffles were elected in near equal proportion in the Grande Ronde and Inmaha basins. Within streams, use was similar between years. Almost all salmon were observed in association with cover, but the type of cover largely reflected availablity. Chinook salmon elected the deepest depths within channel units (microhabitat scale), but not necessarily the deepest channel units among streams (channel unit scale). Chinook salmon did not elect cooler stream temperatures within channel units in any study stream, except the Middle Fork John Day River. Radio-tagged chinook showed a high fidelity to habitats, except when stream temperatures approached lethal limits. Due to stream specific differences in habitat availability and use, multiscale habitat assessments for individual streams are recommended to increase the success of watershed restoration activities. Close

• 89. [Article] Distribution, habitat use, and growth of juvenile Chinook salmon in the Metolius River Basin, Oregon

  Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at ...

  Citation × Citation Citation Abstract Copy Title: Distribution, habitat use, and growth of juvenile Chinook salmon in the Metolius River Basin, Oregon Author: Lovtang, Jens C. Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at the Pelton Round Butte Hydroelectric Project on the Deschutes River. Plans have been developed to reestablish passage of anadromous fish through the Project. However, only anecdotal evidence exists on the historic distribution of spring Chinook juveniles in the Basin. A recent approach to characterizing habitat quality for anadromous fishes in the Basin was the development of HabRate (Burke et al. In Press), which presented a relative quality rating of habitat based upon published fish-habitat relationships at the stream reach spatial scale. The present study was initiated to test the predictions of HabRate for summer rearing juvenile Chinook salmon in the Metolius Basin. Chinook salmon fry were released in the winters of 2002 and 2003, and their densities and sizes were quantified via snorkeling and fish collection in six unique study reaches in the upper Metolius River Basin. Each of these stream reaches varied in terms of temperature, habitat availability, invertebrate drift availability, and fish community composition. My observations were not consistent with the qualitative predictions of HabRate. Moreover, habitat utilization was not consistent among study reaches. Similar to other qualitative habitat rating models (e.g. Habitat Suitability Indices (Raleigh et al. 1986) and Instream Flow Incremental Methodology (Bovee 1982)), HabRate's predictions rely solely on physical habitat characteristics, with the assumption that habitat will be used consistently among stream reaches (i.e. a pool in one reach is of equal importance as a pool in another reach). My results suggest that the unique ecological setting of each study reach provides the context for understanding the patterns of growth, habitat use, and diurnal activity of juvenile Chinook salmon. The inclusion of ecological components, such as food availability, the bioenergetic constraints of temperature, and the risk of predation can make these models more biologically realistic. Growth of juvenile Chinook salmon among study reaches had a curvilinear relationship to water temperature, and was also positively related to the drift density of invertebrate biomass. In three collection seasons (fall 2002, spring 2003 and fall 2003) 41 to 69% of the variations in fork lengths were explained by a multiple regression model including temperature and invertebrate drift. Based on these findings, I present a conceptual growth capacity model based on the tenets of bioenergetics as a basis for understanding the relative quality of the habitat among stream reaches for juvenile Chinook salmon. Fish community composition can help to explain observed patterns in habitat utilization and diel activity patterns. In the study reaches that had a greater presence of adult trout (potential predators), observations of juvenile Chinook salmon in mid-channel habitat were infrequent to non-existent during the day and abundances were higher in all habitat types at night. In the study reaches with colder water temperatures, observed juvenile Chinook salmon densities were higher at night. I suggest that habitat selection and diurnal activity patterns in some study reaches are reflective of strategies taken by the fish to minimize risks of predation. Title: Distribution, habitat use, and growth of juvenile Chinook salmon in the Metolius River Basin, Oregon Author: Lovtang, Jens C. Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at the Pelton Round Butte Hydroelectric Project on the Deschutes River. Plans have been developed to reestablish passage of anadromous fish through the Project. However, only anecdotal evidence exists on the historic distribution of spring Chinook juveniles in the Basin. A recent approach to characterizing habitat quality for anadromous fishes in the Basin was the development of HabRate (Burke et al. In Press), which presented a relative quality rating of habitat based upon published fish-habitat relationships at the stream reach spatial scale. The present study was initiated to test the predictions of HabRate for summer rearing juvenile Chinook salmon in the Metolius Basin. Chinook salmon fry were released in the winters of 2002 and 2003, and their densities and sizes were quantified via snorkeling and fish collection in six unique study reaches in the upper Metolius River Basin. Each of these stream reaches varied in terms of temperature, habitat availability, invertebrate drift availability, and fish community composition. My observations were not consistent with the qualitative predictions of HabRate. Moreover, habitat utilization was not consistent among study reaches. Similar to other qualitative habitat rating models (e.g. Habitat Suitability Indices (Raleigh et al. 1986) and Instream Flow Incremental Methodology (Bovee 1982)), HabRate's predictions rely solely on physical habitat characteristics, with the assumption that habitat will be used consistently among stream reaches (i.e. a pool in one reach is of equal importance as a pool in another reach). My results suggest that the unique ecological setting of each study reach provides the context for understanding the patterns of growth, habitat use, and diurnal activity of juvenile Chinook salmon. The inclusion of ecological components, such as food availability, the bioenergetic constraints of temperature, and the risk of predation can make these models more biologically realistic. Growth of juvenile Chinook salmon among study reaches had a curvilinear relationship to water temperature, and was also positively related to the drift density of invertebrate biomass. In three collection seasons (fall 2002, spring 2003 and fall 2003) 41 to 69% of the variations in fork lengths were explained by a multiple regression model including temperature and invertebrate drift. Based on these findings, I present a conceptual growth capacity model based on the tenets of bioenergetics as a basis for understanding the relative quality of the habitat among stream reaches for juvenile Chinook salmon. Fish community composition can help to explain observed patterns in habitat utilization and diel activity patterns. In the study reaches that had a greater presence of adult trout (potential predators), observations of juvenile Chinook salmon in mid-channel habitat were infrequent to non-existent during the day and abundances were higher in all habitat types at night. In the study reaches with colder water temperatures, observed juvenile Chinook salmon densities were higher at night. I suggest that habitat selection and diurnal activity patterns in some study reaches are reflective of strategies taken by the fish to minimize risks of predation. Close

• 90. [Article] Habitat parameters associated with the distribution of seven willow species on a stream in southeastern Oregon

  Thirteen different habitat parameters were measured either quantitatively or qualitatively around seven different Salix (willow) species on a defined reach of stream on the southwestern slope of Steens ...

  Citation × Citation Citation Abstract Copy Title: Habitat parameters associated with the distribution of seven willow species on a stream in southeastern Oregon Author: Gilbert, Griffith J. Thirteen different habitat parameters were measured either quantitatively or qualitatively around seven different Salix (willow) species on a defined reach of stream on the southwestern slope of Steens Mountain in southeastern Oregon in order to both broaden the current information base of riparian ecology and inform future willow plantings aimed at improving riparian habitat. Willow species included in the research were: S. lemmonii (Lemmon willow), S. scouleriana (Scouler willow), S. boothii (Booth willow), S. geyeriana (Geyer willow), S. exigua (coyote willow), S. lasiandra (whiplash willow), and S. lutea (yellow willow). The habitat parameters measured were: height and distance of willow individual from stream channel bankfull elevation, stream channel slope, entrenchment ratio, width-to-depth ratio, watershed elevation, valley azimuth, valley width, soil rock size distribution, soil texture, and winter air temperature. Logistic regression models were built to describe probabilities of occurrence for five out of the seven willow species based on the habitat data collected. Multi-response permutation procedures were performed to describe differences between respective willow habitats. Booth and Geyer willow habitats were best described by watershed elevation as these species dominated the research stream channel’s upper reaches. Whiplash willow habitat was best described by stream channel entrenchment and width-to-depth ratio as this species occurred, on average, in habitats with high stream channel entrenchment and width-to-depth ratios. Specifically, the odds of whiplash willow occurrence are expected to increase by 17% with a unit increase in width-to-depth ratio. Yellow willow habitat was best described by watershed elevation and stream channel width-to-depth ratio as this species occurred only on the lower reaches of the research stream channel. Lemmon willow habitat was best described by interactions between watershed elevation and valley azimuth and between stream channel slope and width-to-depth ratio as the first of these interactions worked to create air temperatures favorable for species occurrence. Coyote willow habitat was best described by stream channel slope, entrenchment, and width-todepth ratio as this species occurred, on average, in habitats with combinations of stream channel slopes, entrenchment, and width-to-depth ratios able to promote frequent streambank rejuvenation. Scouler willow habitat was best described by stream channel entrenchment ratio, as well as interactions between watershed elevation and valley azimuth and between stream channel slope and width-to-depth ratio. Specifically, the odds of Scouler willow occurrence are expected to decrease by 89% with a unit increase in entrenchment ratio. Scouler willow, on average, occurs in habitats with air temperature dynamics similar to those described above for Lemmon willow, and on hydraulically efficient stream channels with low entrenchment and width-to-depth ratios. Title: Habitat parameters associated with the distribution of seven willow species on a stream in southeastern Oregon Author: Gilbert, Griffith J. Thirteen different habitat parameters were measured either quantitatively or qualitatively around seven different Salix (willow) species on a defined reach of stream on the southwestern slope of Steens Mountain in southeastern Oregon in order to both broaden the current information base of riparian ecology and inform future willow plantings aimed at improving riparian habitat. Willow species included in the research were: S. lemmonii (Lemmon willow), S. scouleriana (Scouler willow), S. boothii (Booth willow), S. geyeriana (Geyer willow), S. exigua (coyote willow), S. lasiandra (whiplash willow), and S. lutea (yellow willow). The habitat parameters measured were: height and distance of willow individual from stream channel bankfull elevation, stream channel slope, entrenchment ratio, width-to-depth ratio, watershed elevation, valley azimuth, valley width, soil rock size distribution, soil texture, and winter air temperature. Logistic regression models were built to describe probabilities of occurrence for five out of the seven willow species based on the habitat data collected. Multi-response permutation procedures were performed to describe differences between respective willow habitats. Booth and Geyer willow habitats were best described by watershed elevation as these species dominated the research stream channel’s upper reaches. Whiplash willow habitat was best described by stream channel entrenchment and width-to-depth ratio as this species occurred, on average, in habitats with high stream channel entrenchment and width-to-depth ratios. Specifically, the odds of whiplash willow occurrence are expected to increase by 17% with a unit increase in width-to-depth ratio. Yellow willow habitat was best described by watershed elevation and stream channel width-to-depth ratio as this species occurred only on the lower reaches of the research stream channel. Lemmon willow habitat was best described by interactions between watershed elevation and valley azimuth and between stream channel slope and width-to-depth ratio as the first of these interactions worked to create air temperatures favorable for species occurrence. Coyote willow habitat was best described by stream channel slope, entrenchment, and width-todepth ratio as this species occurred, on average, in habitats with combinations of stream channel slopes, entrenchment, and width-to-depth ratios able to promote frequent streambank rejuvenation. Scouler willow habitat was best described by stream channel entrenchment ratio, as well as interactions between watershed elevation and valley azimuth and between stream channel slope and width-to-depth ratio. Specifically, the odds of Scouler willow occurrence are expected to decrease by 89% with a unit increase in entrenchment ratio. Scouler willow, on average, occurs in habitats with air temperature dynamics similar to those described above for Lemmon willow, and on hydraulically efficient stream channels with low entrenchment and width-to-depth ratios. Close