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• 71. [Image] Influences of human activity on stream temperatures and existence of cold-water fish in streams with elevated temperature: report of a workshop: Independent Multidisciplinary Science Team, Corvallis, OR, October 5-6, 2000

  	Executive Summary The Independent Multidisciplinary Science Team (IMST) convened a panel of experts on stream temperature and fish ecology on October 5-6, 2000 for a scientific workshop on human influences ...
  	Citation × Citation Citation Abstract Copy Title: Influences of human activity on stream temperatures and existence of cold-water fish in streams with elevated temperature: report of a workshop: Independent Multidisciplinary Science Team, Corvallis, OR, October 5-6, 2000 Author: Independent Multidisciplinary Science Team (Oregon) Year: 2000, 2008, 2005 Executive Summary The Independent Multidisciplinary Science Team (IMST) convened a panel of experts on stream temperature and fish ecology on October 5-6, 2000 for a scientific workshop on human influences on stream temperature and responses by salmonids. The workshop was designed to review and discuss scientifically credible data and publications about 1) factors related to human activity that influence stream temperature and 2) behavioral, physical, and ecological mechanisms of cold water fish species for existing in streams with elevated temperatures. The goal of the workshop was to review empirical evidence and to identify points of agreement, disagreement, and knowledge gaps within the scientific community concerning the factors that influence stream temperature and fish responses to elevated temperatures. This information will assist the IMST in preparing a broader temperature report on Oregon's stream temperature water quality standards and their implementation. This report is prepared by the IMST. It was reviewed by workshop participants and revised by the IMST accordingly. The report includes abstracts of plenary presentations on factors that influence stream temperatures and fish responses, and the results of group discussions. The workshop participants focused on three main questions and were asked to list statements of agreement and disagreement, and to identify gaps in the scientific knowledge related to each question: ? How and where does riparian vegetation influence stream temperature? ? Do other changes in streams cause increases in stream temperature? ? How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? The workshop participants provided answers to the questions in the form of bullets. The answers below represent the IMST's summation of the workshop findings and were reviewed by the participants. Several gaps in the scientific basis for specific questions or relationships were identified. The participants found no areas of disagreement for which technical information was available. They noted that any disagreements were not related to scientific interpretation, but were based on concerns or opinions about application, regulation, and management. How and where does riparian vegetation influence stream temperature? The influence of riparian vegetation on stream temperature is cumulative and complex, varying by site, over time, and across regions. Riparian vegetation can directly affect stream temperature by intercepting solar radiation and reducing stream heating. The influence of riparian shade in controlling temperature declines as streams widen in downstream reaches, but the role of riparian vegetation in providing water quality and fish habitat benefits continues to be important. Besides providing shade, riparian vegetation can also indirectly affect stream temperature by influencing microclimate, affecting channel morphology, affecting stream flow, influencing wind speed, affecting humidity, affecting soil temperature, using water, influencing air temperature, enhancing infiltration, and influencing thermal radiation. It is critical to know the site potential to understand what vegetation a site can support. There is not a good scientific understanding of how much vegetation shading is required to affect stream temperature. 1 This lack of understanding may be due to the spatial and temporal variability in landscape components, and the resulting variability in both the direct and indirect influences of vegetation on stream temperature. Therefore, it is difficult to generalize about the effects of vegetation on stream temperature. Do other changes in streams cause increases in stream temperature? The answer to this question is yes, other physical changes in the stream system can modify stream temperatures. Stream temperature is a product of complex interactions between geomorphology, soil, hydrology, vegetation, and climate within a watershed. Changes in these factors will result in changes in stream temperature. Human activities influence stream temperature by affecting one or more of four major components: riparian vegetation, channel morphology, hydrology, and surface/subsurface interactions. Stream systems vary substantially across the landscape, and site-specific information is critical to understanding stream temperature responses to human activities. How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? Workshop participants identified several mechanisms that might explain the ability of fish populations to exist at higher than expected temperatures. The first mechanism was that the fish may have physiological adaptations to survive exposures to high temperatures. A second possibility was that stream habitats may contain cooler microhabitats that fish can occupy as refuge from higher temperatures. A third consideration is that ecological interactions may be different under differing thermal conditions resulting, for example, in changes in disease virulence or cumulative effects of stressors. Finally, since substantial differences exist between laboratory and field studies, it is difficult to apply results of laboratory studies to fish responses in the field. It is important to note that these proposed mechanisms are speculative and, as the list of gaps indicates, substantial experimental work is required to establish their influences on fish in different stream systems. Workshop Summaiy Workshop participants recognized gaps in the available science. Additional knowledge about human influences on stream temperatures and, consequently, influences on cold-water fish populations, will improve our ability to prevent further degradation of stream habitat and will enhance efforts geared towards the recovery of depressed fish populations. Even with these gaps, there was enough agreement on factors that influence stream temperature to indicate information is available to start developing and implementing management practices that are designed to reduce stream warming. It was suggested that managers should consider riparian vegetation, channel morphology, and hydrology, and should account for site differences. Title: Influences of human activity on stream temperatures and existence of cold-water fish in streams with elevated temperature: report of a workshop: Independent Multidisciplinary Science Team, Corvallis, OR, October 5-6, 2000 Author: Independent Multidisciplinary Science Team (Oregon) Year: 2000, 2008, 2005 Executive Summary The Independent Multidisciplinary Science Team (IMST) convened a panel of experts on stream temperature and fish ecology on October 5-6, 2000 for a scientific workshop on human influences on stream temperature and responses by salmonids. The workshop was designed to review and discuss scientifically credible data and publications about 1) factors related to human activity that influence stream temperature and 2) behavioral, physical, and ecological mechanisms of cold water fish species for existing in streams with elevated temperatures. The goal of the workshop was to review empirical evidence and to identify points of agreement, disagreement, and knowledge gaps within the scientific community concerning the factors that influence stream temperature and fish responses to elevated temperatures. This information will assist the IMST in preparing a broader temperature report on Oregon's stream temperature water quality standards and their implementation. This report is prepared by the IMST. It was reviewed by workshop participants and revised by the IMST accordingly. The report includes abstracts of plenary presentations on factors that influence stream temperatures and fish responses, and the results of group discussions. The workshop participants focused on three main questions and were asked to list statements of agreement and disagreement, and to identify gaps in the scientific knowledge related to each question: ? How and where does riparian vegetation influence stream temperature? ? Do other changes in streams cause increases in stream temperature? ? How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? The workshop participants provided answers to the questions in the form of bullets. The answers below represent the IMST's summation of the workshop findings and were reviewed by the participants. Several gaps in the scientific basis for specific questions or relationships were identified. The participants found no areas of disagreement for which technical information was available. They noted that any disagreements were not related to scientific interpretation, but were based on concerns or opinions about application, regulation, and management. How and where does riparian vegetation influence stream temperature? The influence of riparian vegetation on stream temperature is cumulative and complex, varying by site, over time, and across regions. Riparian vegetation can directly affect stream temperature by intercepting solar radiation and reducing stream heating. The influence of riparian shade in controlling temperature declines as streams widen in downstream reaches, but the role of riparian vegetation in providing water quality and fish habitat benefits continues to be important. Besides providing shade, riparian vegetation can also indirectly affect stream temperature by influencing microclimate, affecting channel morphology, affecting stream flow, influencing wind speed, affecting humidity, affecting soil temperature, using water, influencing air temperature, enhancing infiltration, and influencing thermal radiation. It is critical to know the site potential to understand what vegetation a site can support. There is not a good scientific understanding of how much vegetation shading is required to affect stream temperature. 1 This lack of understanding may be due to the spatial and temporal variability in landscape components, and the resulting variability in both the direct and indirect influences of vegetation on stream temperature. Therefore, it is difficult to generalize about the effects of vegetation on stream temperature. Do other changes in streams cause increases in stream temperature? The answer to this question is yes, other physical changes in the stream system can modify stream temperatures. Stream temperature is a product of complex interactions between geomorphology, soil, hydrology, vegetation, and climate within a watershed. Changes in these factors will result in changes in stream temperature. Human activities influence stream temperature by affecting one or more of four major components: riparian vegetation, channel morphology, hydrology, and surface/subsurface interactions. Stream systems vary substantially across the landscape, and site-specific information is critical to understanding stream temperature responses to human activities. How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? Workshop participants identified several mechanisms that might explain the ability of fish populations to exist at higher than expected temperatures. The first mechanism was that the fish may have physiological adaptations to survive exposures to high temperatures. A second possibility was that stream habitats may contain cooler microhabitats that fish can occupy as refuge from higher temperatures. A third consideration is that ecological interactions may be different under differing thermal conditions resulting, for example, in changes in disease virulence or cumulative effects of stressors. Finally, since substantial differences exist between laboratory and field studies, it is difficult to apply results of laboratory studies to fish responses in the field. It is important to note that these proposed mechanisms are speculative and, as the list of gaps indicates, substantial experimental work is required to establish their influences on fish in different stream systems. Workshop Summaiy Workshop participants recognized gaps in the available science. Additional knowledge about human influences on stream temperatures and, consequently, influences on cold-water fish populations, will improve our ability to prevent further degradation of stream habitat and will enhance efforts geared towards the recovery of depressed fish populations. Even with these gaps, there was enough agreement on factors that influence stream temperature to indicate information is available to start developing and implementing management practices that are designed to reduce stream warming. It was suggested that managers should consider riparian vegetation, channel morphology, and hydrology, and should account for site differences. Close

• 72. [Article] 2012 Metolius Basin bull trout redd counts

  Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance ...

  Citation × Citation Citation Abstract Copy Title: 2012 Metolius Basin bull trout redd counts Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance management of bull trout ended and protection of bull trout began in 1983 with mandatory catch and release regulations throughout the Metolius River basin. In 1986, the Department initiated annual redd counts for bull trout throughout the basin to document the species status. Redd surveys showed low spawning numbers, and the Department responded by closing all tributaries downstream of Lake Creek to fishing in 1994. A Threatened listing of Columbia River bull trout under the Endangered Species Act in 1998 followed the fishery closure (Fies et al. 1996 and Lohr et al. ####). Bull trout redd counts continue in the basin in accordance with the goals of the Native Fish Conservation Policy. Title: 2012 Metolius Basin bull trout redd counts Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance management of bull trout ended and protection of bull trout began in 1983 with mandatory catch and release regulations throughout the Metolius River basin. In 1986, the Department initiated annual redd counts for bull trout throughout the basin to document the species status. Redd surveys showed low spawning numbers, and the Department responded by closing all tributaries downstream of Lake Creek to fishing in 1994. A Threatened listing of Columbia River bull trout under the Endangered Species Act in 1998 followed the fishery closure (Fies et al. 1996 and Lohr et al. ####). Bull trout redd counts continue in the basin in accordance with the goals of the Native Fish Conservation Policy. Close

• 73. [Article] 2011 Metolius River subbasin bull trout redd counts

  Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance ...

  Citation × Citation Citation Abstract Copy Title: 2011 Metolius River subbasin bull trout redd counts Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance management of bull trout ended and protection of bull trout began in 1983 with mandatory catch and release regulations throughout the Metolius River basin. In 1986, the Department initiated annual redd counts for bull trout throughout the basin to document the species status. Redd surveys showed low spawning numbers, and the Department responded by closing all tributaries downstream of Lake Creek to fishing in 1994. A Threatened listing of Columbia River bull trout under the Endangered Species Act in 1998 followed the fishery closure (Fies et al. 1996 and Lohr et al. ####). Bull trout redd counts continue in the basin in accordance with the goals of the Native Fish Conservation Policy. Title: 2011 Metolius River subbasin bull trout redd counts Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance management of bull trout ended and protection of bull trout began in 1983 with mandatory catch and release regulations throughout the Metolius River basin. In 1986, the Department initiated annual redd counts for bull trout throughout the basin to document the species status. Redd surveys showed low spawning numbers, and the Department responded by closing all tributaries downstream of Lake Creek to fishing in 1994. A Threatened listing of Columbia River bull trout under the Endangered Species Act in 1998 followed the fishery closure (Fies et al. 1996 and Lohr et al. ####). Bull trout redd counts continue in the basin in accordance with the goals of the Native Fish Conservation Policy. Close

• 74. [Article] 2010 Metolius Basin bull trout redds

  Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance ...

  Citation × Citation Citation Abstract Copy Title: 2010 Metolius Basin bull trout redds Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance management of bull trout ended and protection of bull trout began in 1983 with mandatory catch and release regulations throughout the Metolius River basin. In 1986, the Department initiated annual redd counts for bull trout throughout the basin to document the species status. Redd surveys showed low spawning numbers, and the Department responded by closing all tributaries downstream of Lake Creek to fishing in 1994. A Threatened listing of Columbia River bull trout under the Endangered Species Act in 1998 followed the fishery closure (Fies et al. 1996 and Lohr et al. ####). Bull trout redd counts continue in the basin in accordance with the goals of the Native Fish Conservation Policy. Title: 2010 Metolius Basin bull trout redds Abstract -- Bull trout are indigenous to the Metolius River basin; however, they were managed as a nuisance species due to their interactions with anadromous sportfish for several decades. In 1960, nuisance management of bull trout ended and protection of bull trout began in 1983 with mandatory catch and release regulations throughout the Metolius River basin. In 1986, the Department initiated annual redd counts for bull trout throughout the basin to document the species status. Redd surveys showed low spawning numbers, and the Department responded by closing all tributaries downstream of Lake Creek to fishing in 1994. A Threatened listing of Columbia River bull trout under the Endangered Species Act in 1998 followed the fishery closure (Fies et al. 1996 and Lohr et al. ####). Bull trout redd counts continue in the basin in accordance with the goals of the Native Fish Conservation Policy. Close

• 75. [Article] Predicted Redistribution of Ceratomyxa shasta Genotypes with Salmonid Passage in the Deschutes River, Oregon

  This is the publisher’s final pdf. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandf.co.uk/journals/.

  Citation × Citation Citation Abstract Copy Title: Predicted Redistribution of Ceratomyxa shasta Genotypes with Salmonid Passage in the Deschutes River, Oregon Author: Bartholomew, Jerri L., Stinson, Matthew E. T. This is the publisher’s final pdf. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandf.co.uk/journals/. Title: Predicted Redistribution of Ceratomyxa shasta Genotypes with Salmonid Passage in the Deschutes River, Oregon Author: Bartholomew, Jerri L., Stinson, Matthew E. T. This is the publisher’s final pdf. The published article is copyrighted by Taylor & Francis and can be found at: http://www.tandf.co.uk/journals/. Close

• 76. [Article] A study of Myxobolus cerebralis in the Lostine River, Oregon : epizootiology, distribution and implications for resident and anadromous salmonids

  Myxobolus cerebralis, a myxozoan parasite that infects almost all species of wild and cultured salmonids, was first identified in northeastern Oregon in the Lostine River in 1986. Fish that are heavily ...

  Citation × Citation Citation Abstract Copy Title: A study of Myxobolus cerebralis in the Lostine River, Oregon : epizootiology, distribution and implications for resident and anadromous salmonids Author: Sandell, Todd A. Myxobolus cerebralis, a myxozoan parasite that infects almost all species of wild and cultured salmonids, was first identified in northeastern Oregon in the Lostine River in 1986. Fish that are heavily infected with M. cerebralis develop whirling disease, which was determined to be the cause of catastrophic declines in rainbow trout populations in Montana and Colorado in 1996. There have been no reports of severe salmonid population declines attributed to whirling disease in Oregon, although many populations are at levels that warrant protective listing under the Endangered Species Act. This study was undertaken to I) establish the distribution and seasonal prevalence of M. cerebralis infection in the Lostine River, 2) investigate the epizootiological factors influencing the occurrence of whirling disease in this river, 3) determine the potential impact of the parasite on chinook salmon, and 4) evaluate the suitability of a non-lethal tissue sampling protocol for the detection of M. cerebralis in juvenile and adult salmonids for use in monitoring the effects and distribution of the parasite in protected salmonid populations. Results of this study indicate that the parasite is present throughout the main stem of the Lostine River during all seasons, and that rainbow and anadromous steelhead trout fry emerging in the lower river are most likely to become infected and develop whirling disease. Chinook salmon were shown to be relatively resistant to M. cerebralis at low levels of exposure, but this effect was less evident when the parasite exposure increased. The non-lethal sampling protocol was successful in detecting M. cerebralis in juvenile salmonids but not in adults, where it is most needed. The information gathered during these studies was then correlated with the life histories of resident and anadromous salmonids in the Lostine River to determine the potential impact of M. cerebralis On salmonid populations in this region. Title: A study of Myxobolus cerebralis in the Lostine River, Oregon : epizootiology, distribution and implications for resident and anadromous salmonids Author: Sandell, Todd A. Myxobolus cerebralis, a myxozoan parasite that infects almost all species of wild and cultured salmonids, was first identified in northeastern Oregon in the Lostine River in 1986. Fish that are heavily infected with M. cerebralis develop whirling disease, which was determined to be the cause of catastrophic declines in rainbow trout populations in Montana and Colorado in 1996. There have been no reports of severe salmonid population declines attributed to whirling disease in Oregon, although many populations are at levels that warrant protective listing under the Endangered Species Act. This study was undertaken to I) establish the distribution and seasonal prevalence of M. cerebralis infection in the Lostine River, 2) investigate the epizootiological factors influencing the occurrence of whirling disease in this river, 3) determine the potential impact of the parasite on chinook salmon, and 4) evaluate the suitability of a non-lethal tissue sampling protocol for the detection of M. cerebralis in juvenile and adult salmonids for use in monitoring the effects and distribution of the parasite in protected salmonid populations. Results of this study indicate that the parasite is present throughout the main stem of the Lostine River during all seasons, and that rainbow and anadromous steelhead trout fry emerging in the lower river are most likely to become infected and develop whirling disease. Chinook salmon were shown to be relatively resistant to M. cerebralis at low levels of exposure, but this effect was less evident when the parasite exposure increased. The non-lethal sampling protocol was successful in detecting M. cerebralis in juvenile salmonids but not in adults, where it is most needed. The information gathered during these studies was then correlated with the life histories of resident and anadromous salmonids in the Lostine River to determine the potential impact of M. cerebralis On salmonid populations in this region. Close

• 77. [Article] The present state of the Columbia River salmon resources

  Reprinted from Proceedings of the Sixth Pacific Science Congress, University of California Press, Berkeley, California, 1941.

  Citation × Citation Citation Abstract Copy Title: The present state of the Columbia River salmon resources Author: Oregon. Fish Commission. Research Dept., Rich, Willis H. (Willis Horton), 1885-1972 Reprinted from Proceedings of the Sixth Pacific Science Congress, University of California Press, Berkeley, California, 1941. Title: The present state of the Columbia River salmon resources Author: Oregon. Fish Commission. Research Dept., Rich, Willis H. (Willis Horton), 1885-1972 Reprinted from Proceedings of the Sixth Pacific Science Congress, University of California Press, Berkeley, California, 1941. Close

• 78. [Article] The salmon runs of the Columbia River in 1938

  Exceptional data are available for the study of the salmon runs of the Columbia River in 1938. Detailed figures on catch were supplied by Oregon and Washington in such form that they could readily be combined ...

  Citation × Citation Citation Abstract Copy Title: The salmon runs of the Columbia River in 1938 Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 Exceptional data are available for the study of the salmon runs of the Columbia River in 1938. Detailed figures on catch were supplied by Oregon and Washington in such form that they could readily be combined with the counts at Bonneville Dam to provide a basis for estimating the escapement. Tables show the catch of each species for each week in each of six zones, and the counts at Bonneville and Rock Island dams. The general course of the run of each species is shown. The numbers of fish bound for the spawning grounds above Rock Island Dam are estimated as follows: Chinook salmon entering Columbia River before May 1, 4 percent; during May, 6 percent; June and July, 15 percent; and August to December, 1 percent. Blueback salmon entering the river during the above periods, 40 percent. Steelhead trout entering the river during June to September, 1 percent; during the rest of the year, 10 percent. Fishing intensities are shown by escapement to catch ratios. Percentages of chinook salmon escapement are less than 15 during May; 17 during June and July; and 33 during the remainder of the year. The June and July runs are now greatly depleted, and an important part of these runs spawns above Rock Island Dam. The blueback salmon escapement is about 20 percent, and of steelhead trout about 33 percent. Weekly and seasonal closed periods are shown to be almost entirely ineffective for increasing the spawning escapement. Exploitation is further increased by the intensive troll fishery conducted from Monterey Bay to southeastern Alaska. Chinook salmon are also subjected to a sport fishery of considerable importance. Main runs of salmon to the Columbia River are practically unprotected and are fished with destructive intensity. Title: The salmon runs of the Columbia River in 1938 Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 Exceptional data are available for the study of the salmon runs of the Columbia River in 1938. Detailed figures on catch were supplied by Oregon and Washington in such form that they could readily be combined with the counts at Bonneville Dam to provide a basis for estimating the escapement. Tables show the catch of each species for each week in each of six zones, and the counts at Bonneville and Rock Island dams. The general course of the run of each species is shown. The numbers of fish bound for the spawning grounds above Rock Island Dam are estimated as follows: Chinook salmon entering Columbia River before May 1, 4 percent; during May, 6 percent; June and July, 15 percent; and August to December, 1 percent. Blueback salmon entering the river during the above periods, 40 percent. Steelhead trout entering the river during June to September, 1 percent; during the rest of the year, 10 percent. Fishing intensities are shown by escapement to catch ratios. Percentages of chinook salmon escapement are less than 15 during May; 17 during June and July; and 33 during the remainder of the year. The June and July runs are now greatly depleted, and an important part of these runs spawns above Rock Island Dam. The blueback salmon escapement is about 20 percent, and of steelhead trout about 33 percent. Weekly and seasonal closed periods are shown to be almost entirely ineffective for increasing the spawning escapement. Exploitation is further increased by the intensive troll fishery conducted from Monterey Bay to southeastern Alaska. Chinook salmon are also subjected to a sport fishery of considerable importance. Main runs of salmon to the Columbia River are practically unprotected and are fished with destructive intensity. Close

• 79. [Article] Abundance, distribution, and migratory behavior of coastal cutthroat trout in two lower Columbia River tributaries

  Abstract -- Coastal cutthroat trout (Oncorhynchus clarki clarki) exhibit multiple life history types characterized by diverse migratory strategies, including anadromous, potomodromous, and freshwater resident ...

  Citation × Citation Citation Abstract Copy Title: Abundance, distribution, and migratory behavior of coastal cutthroat trout in two lower Columbia River tributaries Abstract -- Coastal cutthroat trout (Oncorhynchus clarki clarki) exhibit multiple life history types characterized by diverse migratory strategies, including anadromous, potomodromous, and freshwater resident forms. The factors contributing to life history variation within populations are not well understood, but probably are not strictly genetic (e.g. Johnson et al, in review). Variation in migration tendency within cutthroat populations may result from phenotype plasticity, influenced by density, frequency, or condition dependent processes (Hendry et al. 2004). For example, an individual cutthroat’s choice to migrate at a given time or age may be a response to environmental conditions mediated by a genetically determined reaction norm (Hutchings 2004). This report summarizes a study undertaken to describe the expression of migratory behavior within coastal cutthroat trout populations, the relationship among migratory and non-migratory individuals, and the implications of life history diversity for management of cutthroat trout in tributaries of the lower Columbia River. The relationship between resident and migratory populations (or resident and migratory individuals within populations) is of central importance for management of coastal cutthroat trout. In the lower Columbia River and southwest Washington State a proposed rule to list anadromous cutthroat as threatened under the federal Endangered Species Act (ESA) was withdrawn after the US Fish and Wildlife Service (USFWS) decided during its review process to include resident and anadromous forms in the same Distinct Population Segment (DPS). Debate over proposed ESA listing highlighted a general lack of knowledge about coastal cutthroat trout life history, relationships between resident and migratory forms, and estuarine habitat use in the lower Columbia River. In 2009, the decision not to list the DPS as threatened was remanded to the USFWS on the grounds that the Service had not adequately considered whether marine and estuarine habitats formed a significant portion of the range of the DPS (USFWS 2009). We evaluated the distribution and abundance of coastal cutthroat trout in Big Creek and Bear Creek, two tributaries that join the Columbia River estuary from the south (Oregon) side roughly 30 kilometers from the ocean, and monitored the migratory behavior of cutthroat that emigrated from these streams and entered the Columbia River estuary. Big Creek is an interesting system because a fish weir and diversion dam at an ODFW hatchery, established in 1941 and refurbished in 1957, prevent cutthroat trout from passing upstream, isolating the cutthroat spawning population above the hatchery. Despite this barrier to upstream migration, offspring of resident cutthroat in the upper watershed continue to “smolt” and migrate downstream past the barrier. We were interested in the fate of these fish and their contribution to the adult population. Bear Creek, on the other hand, has always had full access for anadromous cutthroat through much of its drainage. These two systems permit a comparison of life history characteristics, migration, and survival of coastal cutthroat rearing in streams above and below migration barriers, and provide study sites in Oregon to compliment research by USFWS of coastal cutthroat migration behavior in tributaries entering the estuary from the north side of the Columbia River (USFWS 2008; and see Hudson et al. 2008; Johnson 2008; Zydlewski et al. 2008). A major objective of our work in Big Creek and Bear Creek was to increase understanding of coastal cutthroat trout biology and the relationship between resident and migratory cutthroat in lower Columbia tributaries. Additionally, we sought to document habitat use in the Columbia River estuary by migrant cutthroat. Our specific objectives were to: • Estimate abundance of coastal cutthroat trout in Big Creek (above hatchery barrier) and Bear Creek (above and below a large dam) • Quantify the proportions of the cutthroat populations that are migratory, identify which individuals migrate and describe the timing of migration • Describe habitats used by anadromous migrants and characterize migration behavior within the Columbia River estuary • Measure estuarine/marine survival of anadromous individuals and document return to natal streams Title: Abundance, distribution, and migratory behavior of coastal cutthroat trout in two lower Columbia River tributaries Abstract -- Coastal cutthroat trout (Oncorhynchus clarki clarki) exhibit multiple life history types characterized by diverse migratory strategies, including anadromous, potomodromous, and freshwater resident forms. The factors contributing to life history variation within populations are not well understood, but probably are not strictly genetic (e.g. Johnson et al, in review). Variation in migration tendency within cutthroat populations may result from phenotype plasticity, influenced by density, frequency, or condition dependent processes (Hendry et al. 2004). For example, an individual cutthroat’s choice to migrate at a given time or age may be a response to environmental conditions mediated by a genetically determined reaction norm (Hutchings 2004). This report summarizes a study undertaken to describe the expression of migratory behavior within coastal cutthroat trout populations, the relationship among migratory and non-migratory individuals, and the implications of life history diversity for management of cutthroat trout in tributaries of the lower Columbia River. The relationship between resident and migratory populations (or resident and migratory individuals within populations) is of central importance for management of coastal cutthroat trout. In the lower Columbia River and southwest Washington State a proposed rule to list anadromous cutthroat as threatened under the federal Endangered Species Act (ESA) was withdrawn after the US Fish and Wildlife Service (USFWS) decided during its review process to include resident and anadromous forms in the same Distinct Population Segment (DPS). Debate over proposed ESA listing highlighted a general lack of knowledge about coastal cutthroat trout life history, relationships between resident and migratory forms, and estuarine habitat use in the lower Columbia River. In 2009, the decision not to list the DPS as threatened was remanded to the USFWS on the grounds that the Service had not adequately considered whether marine and estuarine habitats formed a significant portion of the range of the DPS (USFWS 2009). We evaluated the distribution and abundance of coastal cutthroat trout in Big Creek and Bear Creek, two tributaries that join the Columbia River estuary from the south (Oregon) side roughly 30 kilometers from the ocean, and monitored the migratory behavior of cutthroat that emigrated from these streams and entered the Columbia River estuary. Big Creek is an interesting system because a fish weir and diversion dam at an ODFW hatchery, established in 1941 and refurbished in 1957, prevent cutthroat trout from passing upstream, isolating the cutthroat spawning population above the hatchery. Despite this barrier to upstream migration, offspring of resident cutthroat in the upper watershed continue to “smolt” and migrate downstream past the barrier. We were interested in the fate of these fish and their contribution to the adult population. Bear Creek, on the other hand, has always had full access for anadromous cutthroat through much of its drainage. These two systems permit a comparison of life history characteristics, migration, and survival of coastal cutthroat rearing in streams above and below migration barriers, and provide study sites in Oregon to compliment research by USFWS of coastal cutthroat migration behavior in tributaries entering the estuary from the north side of the Columbia River (USFWS 2008; and see Hudson et al. 2008; Johnson 2008; Zydlewski et al. 2008). A major objective of our work in Big Creek and Bear Creek was to increase understanding of coastal cutthroat trout biology and the relationship between resident and migratory cutthroat in lower Columbia tributaries. Additionally, we sought to document habitat use in the Columbia River estuary by migrant cutthroat. Our specific objectives were to: • Estimate abundance of coastal cutthroat trout in Big Creek (above hatchery barrier) and Bear Creek (above and below a large dam) • Quantify the proportions of the cutthroat populations that are migratory, identify which individuals migrate and describe the timing of migration • Describe habitats used by anadromous migrants and characterize migration behavior within the Columbia River estuary • Measure estuarine/marine survival of anadromous individuals and document return to natal streams Close

• 80. [Article] Coastal Chinook Salmon Management Plan Summary Mailing, 1991

  Abstract -- The Coastal Chinook Salmon Management Plan is the fourth in a series of individual species plans concerning management of anadromous salmonid populations in Oregon. This plan focuses on actions ...

  Citation × Citation Citation Abstract Copy Title: Coastal Chinook Salmon Management Plan Summary Mailing, 1991 Abstract -- The Coastal Chinook Salmon Management Plan is the fourth in a series of individual species plans concerning management of anadromous salmonid populations in Oregon. This plan focuses on actions the Oregon Department of Fish and Wildlife will take regarding chinook salmon populations produced in Oregon Coastal watersheds from the Necanicum River in the north to the Winchuck River at the Oregon-California border. Management of chinook salmon in the Columbia River Basin - which is guided by a cooperative agreement with Washington, the Columbia River Treaty Indian Tribes, and the Federal Government - is not included in this document. Title: Coastal Chinook Salmon Management Plan Summary Mailing, 1991 Abstract -- The Coastal Chinook Salmon Management Plan is the fourth in a series of individual species plans concerning management of anadromous salmonid populations in Oregon. This plan focuses on actions the Oregon Department of Fish and Wildlife will take regarding chinook salmon populations produced in Oregon Coastal watersheds from the Necanicum River in the north to the Winchuck River at the Oregon-California border. Management of chinook salmon in the Columbia River Basin - which is guided by a cooperative agreement with Washington, the Columbia River Treaty Indian Tribes, and the Federal Government - is not included in this document. Close