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• 1. [Article] Policy Analysis for Optimizing Native Fisheries on the McKenzie River

  The impact of hatchery fish on native populations has been extensively studies, especially as environmental management has generally moved toward a conservation focus. In Oregon, the McKenzie River native ...

  Citation × Citation Citation Abstract Copy Title: Policy Analysis for Optimizing Native Fisheries on the McKenzie River Author: Ray, Mary Year: 2001 The impact of hatchery fish on native populations has been extensively studies, especially as environmental management has generally moved toward a conservation focus. In Oregon, the McKenzie River native rainbow trout population has been the focus of recent interest groups attempting to induce a change in management practices to support native fisheries. The McKenzie River Chapter of Trout Unlimited is interested in learning more about the impacts that hatchery stocked rainbow trout have on native river populations. It is the group's intent to seek a rule change to management by the Oregon Department of Fish and Wildlife. A review of the historical and scientific information regarding fish stocking was needed to provide information for Trout Unlimited to make informed recommendations to the managing agency. Examples of successful management changes for conservation of native fish were used as case studies to examine the implications of stocking cessation on the viability of trout populations in Oregon. This paper provides details on the background information needed to understand the case studies, their relation to the situation on the McKenzie, and how those outcomes may support recommendations for fisheries management on the McKenzie. It is the intent that these recommendations and supporting details may provide Trout Unlimited with the information needed to make a meaningful recommendation to the Oregon Department of Fish and Wildlife regarding the native rainbow trout fishery in the McKenzie. Title: Policy Analysis for Optimizing Native Fisheries on the McKenzie River Author: Ray, Mary Year: 2001 The impact of hatchery fish on native populations has been extensively studies, especially as environmental management has generally moved toward a conservation focus. In Oregon, the McKenzie River native rainbow trout population has been the focus of recent interest groups attempting to induce a change in management practices to support native fisheries. The McKenzie River Chapter of Trout Unlimited is interested in learning more about the impacts that hatchery stocked rainbow trout have on native river populations. It is the group's intent to seek a rule change to management by the Oregon Department of Fish and Wildlife. A review of the historical and scientific information regarding fish stocking was needed to provide information for Trout Unlimited to make informed recommendations to the managing agency. Examples of successful management changes for conservation of native fish were used as case studies to examine the implications of stocking cessation on the viability of trout populations in Oregon. This paper provides details on the background information needed to understand the case studies, their relation to the situation on the McKenzie, and how those outcomes may support recommendations for fisheries management on the McKenzie. It is the intent that these recommendations and supporting details may provide Trout Unlimited with the information needed to make a meaningful recommendation to the Oregon Department of Fish and Wildlife regarding the native rainbow trout fishery in the McKenzie. Close

• 2. [Article] Understanding the Importance of Intermittently Fragmented Stream Habitat for Isolated Westslope Cutthroat Trout (<i>Oncorhynchus clarki lewisi</i>) in the Colville National Forest, Washington

  Climate change and anthropogenic effects have vastly reduced Westslope Cutthroat Trout (Oncorhynchus clarki lewisi, WCT) habitat throughout their range, including the Colville National Forest in northeastern ...

  Citation × Citation Citation Abstract Copy Title: Understanding the Importance of Intermittently Fragmented Stream Habitat for Isolated Westslope Cutthroat Trout (<i>Oncorhynchus clarki lewisi</i>) in the Colville National Forest, Washington Author: Carpenter, Forrest Michael Year: 2016 Climate change and anthropogenic effects have vastly reduced Westslope Cutthroat Trout (Oncorhynchus clarki lewisi, WCT) habitat throughout their range, including the Colville National Forest in northeastern Washington where this study was conducted. Many native salmonid populations have declined in abundance since the early 1900s due to a variety of climate- and human-driven forces. Westslope Cutthroat Trout are especially sensitive to habitat loss or degradation and to climate change. Together, climate change, habitat degradation, and non-native salmonid invasions are contributing to increasingly fragmented WCT populations. Ongoing and predicted future warming trends are expected to further fragment these populations and isolate them in headwater stream reaches, with populations in the spatial margins of their distributions facing greater risk. Native salmonid populations are often separated or isolated by natural or artificial upstream migration barriers (i.e., waterfalls, culverts, etc.). Prior to continuing conservation and management actions targeting WCT, it is imperative to understand habitat requirements of this keystone species in fragmented areas. Field survey data were collected in the summer of 2015 on channel geomorphic characteristics and WCT presence/absence in 26 streams located in the Colville National Forest. A clear spatial separation was observed between Eastern Brook Trout (Salvenius fontinalis, EBT) and WCT above four culvert road crossings and the habitat in both of these areas was compared statistically to identify explicit differences. This dataset was also analyzed using logistic regression modeling to determine the best habitat predictors of the presence of isolated WCT populations existing upstream of these crossing. In general, stream habitat in the Middle and South Forks of Mill Creek had low large substrate, high fine sediments, and exhibited pool-riffle channel morphology. Pool habitat supporting isolated WCT was significantly smaller, in terms of volume and surface area, than pool habitat supporting sympatric populations of WCT and EBT, largely due to the headwater nature of channel units supporting isolated WCT populations. Additionally, due to the extreme drought conditions during 2015, stream flow was substantially diminished in the study area causing these reaches to be highly fragmented and largely disconnected from the rest of the stream channel. Fine sediments were generally higher in headwater reaches supporting isolated WCT, including in pools and riffles, which was unexpected, mainly because they exist above sediment delivery points in the longitudinal extent of the system. Logistic regression analysis indicated that the presence of isolated WCT populations was primarily positively associated with an increase in large wood and boulders, and negatively associated with increasing gravel, bedrock, habitat unit length, depth, and width (Significant x2, R2=0.174, misclassification rate = 14.9%, α=0.05). The final model correctly predicted 37.5% of isolated WCT presence observations and 96.5% of the WCT/EBT presence observations significantly better than by chance alone (k=0.81). This model, in fact, may be useful in identifying limited habitat due to the fragmented nature of the channel units supporting IWCT. Large wood and boulders were positively correlated to WCT presence, likely because both are important in the formation of pools and cascades. Channel unit length, width, depth, active channel width as well as gravel and bedrock substrates, were all negatively associated with WCT presence. This suggests that isolated WCT are primarily associated with small headwater cascades with complex shelter, which may provide greater thermal and predation refuge compared to shallow glide or large pool habitats. Future model analysis should include additional habitat variables such as water temperature, stream gradient, and species interactions to strengthen the prediction of Westslope Cutthroat Trout presence. Overall, I concluded that differences in stream habitat above and below blocking culverts are not driving Westslope Cutthroat Trout distributions in the study area due to confounding factors such as the presence of problematic barriers and small sample size. I also conclude that future conservation and management decisions specific to WCT should prioritize complex cascade habitat in headwater stream reaches because of the type and quantity of habitat they may provide, especially during severe drought or low flow conditions. Title: Understanding the Importance of Intermittently Fragmented Stream Habitat for Isolated Westslope Cutthroat Trout (<i>Oncorhynchus clarki lewisi</i>) in the Colville National Forest, Washington Author: Carpenter, Forrest Michael Year: 2016 Climate change and anthropogenic effects have vastly reduced Westslope Cutthroat Trout (Oncorhynchus clarki lewisi, WCT) habitat throughout their range, including the Colville National Forest in northeastern Washington where this study was conducted. Many native salmonid populations have declined in abundance since the early 1900s due to a variety of climate- and human-driven forces. Westslope Cutthroat Trout are especially sensitive to habitat loss or degradation and to climate change. Together, climate change, habitat degradation, and non-native salmonid invasions are contributing to increasingly fragmented WCT populations. Ongoing and predicted future warming trends are expected to further fragment these populations and isolate them in headwater stream reaches, with populations in the spatial margins of their distributions facing greater risk. Native salmonid populations are often separated or isolated by natural or artificial upstream migration barriers (i.e., waterfalls, culverts, etc.). Prior to continuing conservation and management actions targeting WCT, it is imperative to understand habitat requirements of this keystone species in fragmented areas. Field survey data were collected in the summer of 2015 on channel geomorphic characteristics and WCT presence/absence in 26 streams located in the Colville National Forest. A clear spatial separation was observed between Eastern Brook Trout (Salvenius fontinalis, EBT) and WCT above four culvert road crossings and the habitat in both of these areas was compared statistically to identify explicit differences. This dataset was also analyzed using logistic regression modeling to determine the best habitat predictors of the presence of isolated WCT populations existing upstream of these crossing. In general, stream habitat in the Middle and South Forks of Mill Creek had low large substrate, high fine sediments, and exhibited pool-riffle channel morphology. Pool habitat supporting isolated WCT was significantly smaller, in terms of volume and surface area, than pool habitat supporting sympatric populations of WCT and EBT, largely due to the headwater nature of channel units supporting isolated WCT populations. Additionally, due to the extreme drought conditions during 2015, stream flow was substantially diminished in the study area causing these reaches to be highly fragmented and largely disconnected from the rest of the stream channel. Fine sediments were generally higher in headwater reaches supporting isolated WCT, including in pools and riffles, which was unexpected, mainly because they exist above sediment delivery points in the longitudinal extent of the system. Logistic regression analysis indicated that the presence of isolated WCT populations was primarily positively associated with an increase in large wood and boulders, and negatively associated with increasing gravel, bedrock, habitat unit length, depth, and width (Significant x2, R2=0.174, misclassification rate = 14.9%, α=0.05). The final model correctly predicted 37.5% of isolated WCT presence observations and 96.5% of the WCT/EBT presence observations significantly better than by chance alone (k=0.81). This model, in fact, may be useful in identifying limited habitat due to the fragmented nature of the channel units supporting IWCT. Large wood and boulders were positively correlated to WCT presence, likely because both are important in the formation of pools and cascades. Channel unit length, width, depth, active channel width as well as gravel and bedrock substrates, were all negatively associated with WCT presence. This suggests that isolated WCT are primarily associated with small headwater cascades with complex shelter, which may provide greater thermal and predation refuge compared to shallow glide or large pool habitats. Future model analysis should include additional habitat variables such as water temperature, stream gradient, and species interactions to strengthen the prediction of Westslope Cutthroat Trout presence. Overall, I concluded that differences in stream habitat above and below blocking culverts are not driving Westslope Cutthroat Trout distributions in the study area due to confounding factors such as the presence of problematic barriers and small sample size. I also conclude that future conservation and management decisions specific to WCT should prioritize complex cascade habitat in headwater stream reaches because of the type and quantity of habitat they may provide, especially during severe drought or low flow conditions. Close

• 3. [Article] 2005 Diamond Lake Submersed Aquatic Vegetation Survey

  Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern ...

  Citation × Citation Citation Abstract Copy Title: 2005 Diamond Lake Submersed Aquatic Vegetation Survey Author: Sytsma, Mark D., Pfauth, Mary Year: 2006 Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern Cascade Mountains of Oregon, at an elevation of over 5000 feet (>1524 meters). Diamond Lake is a high-use waterbody that supports angling, public campgrounds, recreational boating, swimming, and water skiing. The human activity associated with the lake has been a significant contributor to the economy of southern Oregon since the early part of the twentieth century. Historically Diamond Lake was fishless but since 1910 the lake has been managed as a popular trophy trout fishery. The unauthorized introduction of the tui chub (Gila bicolor) into the lake in the 1930s caused disruption of the food web and a decline in the fishery. In 1954, the Oregon Game Commission constructed a canal near the Lake Creek outlet, lowered the lake level, and treated Diamond Lake with rotenone, to eradicate tui chub. The lake was restocked with trout following the successful rotenone treatment and a fishery was maintained for several decades. In 1992, tui chub were reintroduced, through accidental introduction or intentional illegal stocking, and again caused a decline in the trout fishery. Originally mesotrophic, Diamond Lake Diamond Lake productivity increased over the last century to a eutrophic state, and is currently included on the Oregon Department of Environmental Quality (ODEQ) 303(d) list of water quality limited water bodies for pH and algae. The lake had severe blooms of the cyanobacteria (blue-green algae) Anabaena flos-aquae, which produce neurotoxins, in the summers of 2001, 2002, and 2003. Microcystis aeruginosa, another toxin producing cyanobacterium species, was also present in the 2003 bloom. Diamond Lake was closed to some public uses (wading, swimming, water skiing, and boating) during portions of all three summers due to public health and safety concerns. Algae blooms and declining trout fishery have been attributed to alteration of the food web by the tui chubs. The chubs spawn early and consume the zooplankton in the lake, which reduces grazing pressure on phytoplankton. Since the lake is nitrogen limited, nitrogen-fixing cyanobacteria dominate the phytoplankton community. Therefore, the chubs reduce the quality of the trout fishery by reducing food available for trout and impact water quality by facilitating cyanobacteria blooms, which can be toxic. In response to the impact of the tui chub on Diamond Lake the US Forest Service and Oregon Department of Fish and Wildlife are collaborating in a tui chub eradication effort. The eradication plan includes a 2.4-m (8 ft) drawdown of the lake in the winter and spring of 2006 and a rotenone treatment of remaining lake volume in 2006 to kill any remaining fish. The US Forest Service prepared an EIS for the drawdown and rotenone treatment. Potential impacts of the drawdown on littoral aquatic plant communities were identified in the EIS. The US Forest Service conducted a qualitative survey to develop a species list for the lake. The survey described here provides a quantitative, pretreatment measure of cover and biomass of aquatic plants in Diamond Lake. Follow-up sampling, using similar methods, will permit assessment of changes in the plant community following drawdown and refilling of the lake. Title: 2005 Diamond Lake Submersed Aquatic Vegetation Survey Author: Sytsma, Mark D., Pfauth, Mary Year: 2006 Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern Cascade Mountains of Oregon, at an elevation of over 5000 feet (>1524 meters). Diamond Lake is a high-use waterbody that supports angling, public campgrounds, recreational boating, swimming, and water skiing. The human activity associated with the lake has been a significant contributor to the economy of southern Oregon since the early part of the twentieth century. Historically Diamond Lake was fishless but since 1910 the lake has been managed as a popular trophy trout fishery. The unauthorized introduction of the tui chub (Gila bicolor) into the lake in the 1930s caused disruption of the food web and a decline in the fishery. In 1954, the Oregon Game Commission constructed a canal near the Lake Creek outlet, lowered the lake level, and treated Diamond Lake with rotenone, to eradicate tui chub. The lake was restocked with trout following the successful rotenone treatment and a fishery was maintained for several decades. In 1992, tui chub were reintroduced, through accidental introduction or intentional illegal stocking, and again caused a decline in the trout fishery. Originally mesotrophic, Diamond Lake Diamond Lake productivity increased over the last century to a eutrophic state, and is currently included on the Oregon Department of Environmental Quality (ODEQ) 303(d) list of water quality limited water bodies for pH and algae. The lake had severe blooms of the cyanobacteria (blue-green algae) Anabaena flos-aquae, which produce neurotoxins, in the summers of 2001, 2002, and 2003. Microcystis aeruginosa, another toxin producing cyanobacterium species, was also present in the 2003 bloom. Diamond Lake was closed to some public uses (wading, swimming, water skiing, and boating) during portions of all three summers due to public health and safety concerns. Algae blooms and declining trout fishery have been attributed to alteration of the food web by the tui chubs. The chubs spawn early and consume the zooplankton in the lake, which reduces grazing pressure on phytoplankton. Since the lake is nitrogen limited, nitrogen-fixing cyanobacteria dominate the phytoplankton community. Therefore, the chubs reduce the quality of the trout fishery by reducing food available for trout and impact water quality by facilitating cyanobacteria blooms, which can be toxic. In response to the impact of the tui chub on Diamond Lake the US Forest Service and Oregon Department of Fish and Wildlife are collaborating in a tui chub eradication effort. The eradication plan includes a 2.4-m (8 ft) drawdown of the lake in the winter and spring of 2006 and a rotenone treatment of remaining lake volume in 2006 to kill any remaining fish. The US Forest Service prepared an EIS for the drawdown and rotenone treatment. Potential impacts of the drawdown on littoral aquatic plant communities were identified in the EIS. The US Forest Service conducted a qualitative survey to develop a species list for the lake. The survey described here provides a quantitative, pretreatment measure of cover and biomass of aquatic plants in Diamond Lake. Follow-up sampling, using similar methods, will permit assessment of changes in the plant community following drawdown and refilling of the lake. Close

• 4. [Article] Effects of Types 1 and 2 Herpes Simplex Viruses on Several Fish Tissue Culture Systems

  The purpose of this investigation was to observe changes induced by types 1 and 2 herpes simplex viruses (HSY 1 and HSY 2) when these viruses were cultivated in fish 2 cells. The possibility of attempting ...

  Citation × Citation Citation Abstract Copy Title: Effects of Types 1 and 2 Herpes Simplex Viruses on Several Fish Tissue Culture Systems Author: Harry, Raymond Charles Year: 1977 The purpose of this investigation was to observe changes induced by types 1 and 2 herpes simplex viruses (HSY 1 and HSY 2) when these viruses were cultivated in fish 2 cells. The possibility of attempting to use human strains of herpesviruses in order to transform normal fish tissue culture preparations was considered. Three different fish cell cultures were tested: CHSE-214 cell lines were derived from embryonic chinook salmon (Oncorhynohus tshawytscha), and STE-137 cell lines were obtained from embryonic steelhead trout (Salmo gairdneri). Cells isolated from immature ovaries of rainbow trout (Salmo gairdneri) were propagated by the investigator in these studies. Both HSV 1 and HSV 2 demonstrated cytopathic effects on the 3 different cell types described above when these cells were observed during the exponential growth phase. If virus was added before cells were dividing actively, or when the cells were maintained in a stationary phase of growth, no effect was observed. Several methods were employed in an attempt to trans- form fish cells grown in tissue culture. Different quantities of live virus, preparations of ultraviolet light in- activated virus and purified viral DNA were used in these studies but malignant conversion by known viral components was not achieved. In these experiments, the 2B strain of cells obtained originally from immature ovaries of rainbow trout appeared to undergo spontaneous transformation thereby becoming established as a permanent cell line. To date tissue cultures designated 2B have undergone 25 transfers in this laboratory. Title: Effects of Types 1 and 2 Herpes Simplex Viruses on Several Fish Tissue Culture Systems Author: Harry, Raymond Charles Year: 1977 The purpose of this investigation was to observe changes induced by types 1 and 2 herpes simplex viruses (HSY 1 and HSY 2) when these viruses were cultivated in fish 2 cells. The possibility of attempting to use human strains of herpesviruses in order to transform normal fish tissue culture preparations was considered. Three different fish cell cultures were tested: CHSE-214 cell lines were derived from embryonic chinook salmon (Oncorhynohus tshawytscha), and STE-137 cell lines were obtained from embryonic steelhead trout (Salmo gairdneri). Cells isolated from immature ovaries of rainbow trout (Salmo gairdneri) were propagated by the investigator in these studies. Both HSV 1 and HSV 2 demonstrated cytopathic effects on the 3 different cell types described above when these cells were observed during the exponential growth phase. If virus was added before cells were dividing actively, or when the cells were maintained in a stationary phase of growth, no effect was observed. Several methods were employed in an attempt to trans- form fish cells grown in tissue culture. Different quantities of live virus, preparations of ultraviolet light in- activated virus and purified viral DNA were used in these studies but malignant conversion by known viral components was not achieved. In these experiments, the 2B strain of cells obtained originally from immature ovaries of rainbow trout appeared to undergo spontaneous transformation thereby becoming established as a permanent cell line. To date tissue cultures designated 2B have undergone 25 transfers in this laboratory. Close

• 5. [Article] CE-QUAL-W2 Water Quality and Fish-bioenergetics Model of Chester Morse Lake and the Cedar River

  Many communities are currently seeking to balance urban water needs with preservation of sensitive fish habitat. As part of that effort, CE-QUAL-W2, a hydrodynamic and temperature model, was developed ...

  Citation × Citation Citation Abstract Copy Title: CE-QUAL-W2 Water Quality and Fish-bioenergetics Model of Chester Morse Lake and the Cedar River Author: Wells, Vanessa I. Year: 2011 Many communities are currently seeking to balance urban water needs with preservation of sensitive fish habitat. As part of that effort, CE-QUAL-W2, a hydrodynamic and temperature model, was developed for Chester Morse Lake and the lower Cedar River, WA. Chester Morse Lake is approximately 10 km long with a maximum depth at full pool of 40 m. The Cedar River model started immediately downstream of the Chester Morse dam and ended 21 km downstream at Landsburg, where drinking water is diverted for the City of Seattle. This water quality model was coupled with a fish habitat and bioenergetics model for bull trout and was calibrated to temperature data between 2005 and 2008. Bull trout fish bioenergetics parameters were provided by the USGS. The CE-QUAL-W2 model was found to be highly accurate in modeling temperature variation in the lake - at most locations having an average absolute mean error of between 0.5 and 0.8 oC. The Cedar River model had an average absolute mean error of 0.7oC. This tool is designed to allow managers and operators to estimate the impact to fish habitat and growth potential from various management decisions including extent of drawdown, timing/volume of flows, and various pumping operations. Future studies could include incorporating further water quality parameters such as nutrients, algae, and zooplankton as they relate to fish productivity. Title: CE-QUAL-W2 Water Quality and Fish-bioenergetics Model of Chester Morse Lake and the Cedar River Author: Wells, Vanessa I. Year: 2011 Many communities are currently seeking to balance urban water needs with preservation of sensitive fish habitat. As part of that effort, CE-QUAL-W2, a hydrodynamic and temperature model, was developed for Chester Morse Lake and the lower Cedar River, WA. Chester Morse Lake is approximately 10 km long with a maximum depth at full pool of 40 m. The Cedar River model started immediately downstream of the Chester Morse dam and ended 21 km downstream at Landsburg, where drinking water is diverted for the City of Seattle. This water quality model was coupled with a fish habitat and bioenergetics model for bull trout and was calibrated to temperature data between 2005 and 2008. Bull trout fish bioenergetics parameters were provided by the USGS. The CE-QUAL-W2 model was found to be highly accurate in modeling temperature variation in the lake - at most locations having an average absolute mean error of between 0.5 and 0.8 oC. The Cedar River model had an average absolute mean error of 0.7oC. This tool is designed to allow managers and operators to estimate the impact to fish habitat and growth potential from various management decisions including extent of drawdown, timing/volume of flows, and various pumping operations. Future studies could include incorporating further water quality parameters such as nutrients, algae, and zooplankton as they relate to fish productivity. Close

• 6. [Article] The Chromosome Constitutions of a Hybrid Salmonid and Its Parental Types: Salmo Gairdneri and Salmo Clarki

  A study was undertaken to investigate the application of tissue culture and histochemical banding techniques normally used in mammalian studies to fish cells and to examine the mechanisms of chromosome ...

  Citation × Citation Citation Abstract Copy Title: The Chromosome Constitutions of a Hybrid Salmonid and Its Parental Types: Salmo Gairdneri and Salmo Clarki Author: Jacky, Peter Bruce Year: 1976 A study was undertaken to investigate the application of tissue culture and histochemical banding techniques normally used in mammalian studies to fish cells and to examine the mechanisms of chromosome evolution and speciation in salmonids by comparing the chromosomes of the hybrid to those of the parental types. The application of banding techniques was generally unsuccessful in revealing bands, though quinacrine staining did reveal the presence of two fluorescent spots in the vicinity of the centromere. These were thought to be heterochromatic blocks, possibly related to the high incidence of centric fusion or fission in salmonids. Results of chromosome analysis showerd a higher incidence of acrocentric chromosomes in the hybrid than in either parental type which together with evidence for tetraploidization in salmonids is consistant with some of the requirements for species diversification. Conditions of divergence in chromosome evolution and changes which would have to occur in the hybrid for divergence from the parental types to take place are discussed. The results of a preliminary electrophoretic examination of LDH and esterase activity tended to confirm hybridization. Title: The Chromosome Constitutions of a Hybrid Salmonid and Its Parental Types: Salmo Gairdneri and Salmo Clarki Author: Jacky, Peter Bruce Year: 1976 A study was undertaken to investigate the application of tissue culture and histochemical banding techniques normally used in mammalian studies to fish cells and to examine the mechanisms of chromosome evolution and speciation in salmonids by comparing the chromosomes of the hybrid to those of the parental types. The application of banding techniques was generally unsuccessful in revealing bands, though quinacrine staining did reveal the presence of two fluorescent spots in the vicinity of the centromere. These were thought to be heterochromatic blocks, possibly related to the high incidence of centric fusion or fission in salmonids. Results of chromosome analysis showerd a higher incidence of acrocentric chromosomes in the hybrid than in either parental type which together with evidence for tetraploidization in salmonids is consistant with some of the requirements for species diversification. Conditions of divergence in chromosome evolution and changes which would have to occur in the hybrid for divergence from the parental types to take place are discussed. The results of a preliminary electrophoretic examination of LDH and esterase activity tended to confirm hybridization. Close

• 7. [Article] Gene Expression Life History Markers in a Hatchery and a Wild Population of Young-of-the-Year Oncorhynchus mykiss

  Life history within a single species can vary significantly. Many of these differences are associated with varying environmental conditions. Understanding what environmental conditions cue alternate life ...

  Citation × Citation Citation Abstract Copy Title: Gene Expression Life History Markers in a Hatchery and a Wild Population of Young-of-the-Year Oncorhynchus mykiss Author: Garrett, Ian D. F. Year: 2013 Life history within a single species can vary significantly. Many of these differences are associated with varying environmental conditions. Understanding what environmental conditions cue alternate life histories within a single species has been researched extensively. In salmonid fishes, more than almost any other group, varying environmental conditions give rise to individuals within species that take markedly different life history trajectories. Oncorhynchus mykissis a species of salmonid native to the Pacific Northwest region of North America. This species has two life history forms, anadromous and resident. The anadromous form spends a portion of its life in ocean while the resident life history form completes its entire life history in freshwater. Until the decision to migrate and morphological changes associated with smoltification occur, the two life history variants of this species are indistinguishable from each other. This ambiguity in juvenile O. mykiss morphology presents challenges for conservation managers charged with protecting and increasing threatened O. mykiss populations around the Pacific Northwest because conservation efforts cannot be evaluated until juvenile fish make the decision to migrate. Microarray gene expression analysis was used to profile gene expression in juvenile populations of wild and hatchery O. mykiss to identify gene expression variation associated with alternate life history variants. This analysis identified 8 DNA sequences present in both brain and gill tissues that differ in expression in rainbow trout and steelhead hatchery stocks. Differential expression as quantified by microarrays was validated with quantitative real-time PCR. Lastly, the expression of these putative life history markers was preliminarily evaluated in a wild population of O. mykiss at sample locations in the South Fork John Day River Basin, Oregon with known ratios of juvenile anadromous and resident fish. Title: Gene Expression Life History Markers in a Hatchery and a Wild Population of Young-of-the-Year Oncorhynchus mykiss Author: Garrett, Ian D. F. Year: 2013 Life history within a single species can vary significantly. Many of these differences are associated with varying environmental conditions. Understanding what environmental conditions cue alternate life histories within a single species has been researched extensively. In salmonid fishes, more than almost any other group, varying environmental conditions give rise to individuals within species that take markedly different life history trajectories. Oncorhynchus mykissis a species of salmonid native to the Pacific Northwest region of North America. This species has two life history forms, anadromous and resident. The anadromous form spends a portion of its life in ocean while the resident life history form completes its entire life history in freshwater. Until the decision to migrate and morphological changes associated with smoltification occur, the two life history variants of this species are indistinguishable from each other. This ambiguity in juvenile O. mykiss morphology presents challenges for conservation managers charged with protecting and increasing threatened O. mykiss populations around the Pacific Northwest because conservation efforts cannot be evaluated until juvenile fish make the decision to migrate. Microarray gene expression analysis was used to profile gene expression in juvenile populations of wild and hatchery O. mykiss to identify gene expression variation associated with alternate life history variants. This analysis identified 8 DNA sequences present in both brain and gill tissues that differ in expression in rainbow trout and steelhead hatchery stocks. Differential expression as quantified by microarrays was validated with quantitative real-time PCR. Lastly, the expression of these putative life history markers was preliminarily evaluated in a wild population of O. mykiss at sample locations in the South Fork John Day River Basin, Oregon with known ratios of juvenile anadromous and resident fish. Close

• 8. [Article] Life Cycle, Additions to Biology, and New Hosts of Apophallus Donicus (Trematoda: Heterophyidae) in Oregon

  Apophallus donicus is examined, its life cycle is described, and certain additions are made to its biology. It is thought, but not proven, that eggs are eaten by the first.intermediate host, the local ...

  Citation × Citation Citation Abstract Copy Title: Life Cycle, Additions to Biology, and New Hosts of Apophallus Donicus (Trematoda: Heterophyidae) in Oregon Author: Niemi, Delbert Raymond Year: 1973 Apophallus donicus is examined, its life cycle is described, and certain additions are made to its biology. It is thought, but not proven, that eggs are eaten by the first.intermediate host, the local stream snail FluI menicola virens, and the miracidia escape internally. Mother and daughter rediae stages result, the later producing cercariae which are shed into the water. After burrowing just beneath the skin in suckers (Catostomus macrocheilus Girard), rainbow trout (Salmo 9airdneri Richardson), coho salmon (Oncorhynchus kisutch (Walbaum) squawfish (Ptychocheilus oregonensis Richardson), blackside dace (Rhinichthys osculus nubilus (Girard), redside shiners (Richardsonius balteatus balteatus (Richardson),and possibly other fish, the cercariae encyst and the resulting metacercariae cause black-spot disease in the host. Natural definitive hosts were not found, but laboratory infections included gerbils, white rats, golden hamsters, chickens, catfish (Ictalurus punctatus (Rafinesque), cats, and the author. A rainbow trout was found which had 33 immature Apophallus in its small intestine. All were alive and active, but their entire posterior ends, including all the sex organs, were degenerate and poorly formed compared to the anterior halves of their bodies, and there was no evidence that adults with eggs would have resulted. This trematode is very hardy and adaptable in all stages of its life cycle, e.g., cercariae lived and were active up until eight days after being shed, metacercariae remained infective in fish which had been dead and out of water for 60 hours, and adults lived in tap water at room temperature for 72 hours. Title: Life Cycle, Additions to Biology, and New Hosts of Apophallus Donicus (Trematoda: Heterophyidae) in Oregon Author: Niemi, Delbert Raymond Year: 1973 Apophallus donicus is examined, its life cycle is described, and certain additions are made to its biology. It is thought, but not proven, that eggs are eaten by the first.intermediate host, the local stream snail FluI menicola virens, and the miracidia escape internally. Mother and daughter rediae stages result, the later producing cercariae which are shed into the water. After burrowing just beneath the skin in suckers (Catostomus macrocheilus Girard), rainbow trout (Salmo 9airdneri Richardson), coho salmon (Oncorhynchus kisutch (Walbaum) squawfish (Ptychocheilus oregonensis Richardson), blackside dace (Rhinichthys osculus nubilus (Girard), redside shiners (Richardsonius balteatus balteatus (Richardson),and possibly other fish, the cercariae encyst and the resulting metacercariae cause black-spot disease in the host. Natural definitive hosts were not found, but laboratory infections included gerbils, white rats, golden hamsters, chickens, catfish (Ictalurus punctatus (Rafinesque), cats, and the author. A rainbow trout was found which had 33 immature Apophallus in its small intestine. All were alive and active, but their entire posterior ends, including all the sex organs, were degenerate and poorly formed compared to the anterior halves of their bodies, and there was no evidence that adults with eggs would have resulted. This trematode is very hardy and adaptable in all stages of its life cycle, e.g., cercariae lived and were active up until eight days after being shed, metacercariae remained infective in fish which had been dead and out of water for 60 hours, and adults lived in tap water at room temperature for 72 hours. Close

• 9. [Article] Can Salmonids (Oncorhynchus spp.) Be Identified to Species Using Vertebral Morphometrics?

  Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, ...

  Citation × Citation Citation Abstract Copy Title: Can Salmonids (Oncorhynchus spp.) Be Identified to Species Using Vertebral Morphometrics? Author: Huber, Harriet R., Jorgensen, Jeffery C., Butler, Virginia L., Baker, Greg, Stevens, Rebecca Year: 2011 Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (O. keta), coho (O. kisutch), pink (O.gorbuscha), and sockeye salmon (O. nerka) and cutthroat (O. clarki clarki) and steelhead trout (O. mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000 to 3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A. Title: Can Salmonids (Oncorhynchus spp.) Be Identified to Species Using Vertebral Morphometrics? Author: Huber, Harriet R., Jorgensen, Jeffery C., Butler, Virginia L., Baker, Greg, Stevens, Rebecca Year: 2011 Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (O. keta), coho (O. kisutch), pink (O.gorbuscha), and sockeye salmon (O. nerka) and cutthroat (O. clarki clarki) and steelhead trout (O. mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000 to 3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A. Close

• 10. [Article] Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River

  As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified ...

  Citation × Citation Citation Abstract Copy Title: Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River Author: Butler, Virginia L. Year: 2004 As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified red charr, salmon trout, sturgeon, anchovy, skeet, and other fish that Indians caught and used as trade items with the Corps of Discovery. However, editors of the Lewis and Clark journals have often erred in identifying the fish Lewis and Clark described; the challenge in identifying anadromous fish lies in changing coloration, markings, and examination of habitat. There has been a drastic decline of native fish since 1805 and a growing dominance of exotic species. Title: Where Have All the Native Fish Gone? The Fate of Fish that Lewis and Clark Encountered on the Lower Columbia River Author: Butler, Virginia L. Year: 2004 As part of a special issue of the 'Oregon Historical Quarterly,' discusses the native species of fish in the lower Columbia River described by Meriwether Lewis and William Clark in 1805-06. They identified red charr, salmon trout, sturgeon, anchovy, skeet, and other fish that Indians caught and used as trade items with the Corps of Discovery. However, editors of the Lewis and Clark journals have often erred in identifying the fish Lewis and Clark described; the challenge in identifying anadromous fish lies in changing coloration, markings, and examination of habitat. There has been a drastic decline of native fish since 1805 and a growing dominance of exotic species. Close