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• 1. [Article] Effects of juvenile steelhead on juvenile chinook salmon behavior and physiology

  Experiments were designed to determine whether and how steelhead Oncorhynchus mykiss affect chinook salmon O. tshawytscha when the two species are confined together. In a behavioral experiment, we observed ...

  Citation × Citation Citation Abstract Copy Title: Effects of juvenile steelhead on juvenile chinook salmon behavior and physiology Author: Schreck, Carl B., Congleton, J. L., Kelsey, D. A., Davis, L. E. Experiments were designed to determine whether and how steelhead Oncorhynchus mykiss affect chinook salmon O. tshawytscha when the two species are confined together. In a behavioral experiment, we observed groups of juvenile chinook salmon and steelhead together and groups of chinook salmon alone to determine whether the steelhead were aggressive and their presence changed the behavior of chinook salmon. We also performed two runs of a physiological experiment to determine whether the addition of steelhead to tanks containing chinook salmon would stress the chinook salmon, as determined by a change in their plasma cortisol levels. Behavioral changes were observed in the chinook salmon when they were held with steelhead; they reduced their movements, darted less, were attacked up to 16 times as often, and were found less frequently in the shade than chinook salmon held without steelhead. Steelhead were found to establish territories and defend them with chases, charges, and nips. In their attempts to establish and defend territories, the steelhead attacked the chinook salmon as often as they attacked other steelhead, but the chinook salmon showed little aggression toward the steelhead. Cortisol concentrations were significantly higher for chinook salmon in tanks receiving steelhead than in tanks receiving additional chinook salmon or no additional fish after 2 h (in one of the two experimental runs) and after 32 h (in both experimental runs; combined data). These results suggest that confining steelhead and chinook salmon together, such as in raceways and barges in the Columbia River system and in other situations, is stressful to the chinook salmon. Title: Effects of juvenile steelhead on juvenile chinook salmon behavior and physiology Author: Schreck, Carl B., Congleton, J. L., Kelsey, D. A., Davis, L. E. Experiments were designed to determine whether and how steelhead Oncorhynchus mykiss affect chinook salmon O. tshawytscha when the two species are confined together. In a behavioral experiment, we observed groups of juvenile chinook salmon and steelhead together and groups of chinook salmon alone to determine whether the steelhead were aggressive and their presence changed the behavior of chinook salmon. We also performed two runs of a physiological experiment to determine whether the addition of steelhead to tanks containing chinook salmon would stress the chinook salmon, as determined by a change in their plasma cortisol levels. Behavioral changes were observed in the chinook salmon when they were held with steelhead; they reduced their movements, darted less, were attacked up to 16 times as often, and were found less frequently in the shade than chinook salmon held without steelhead. Steelhead were found to establish territories and defend them with chases, charges, and nips. In their attempts to establish and defend territories, the steelhead attacked the chinook salmon as often as they attacked other steelhead, but the chinook salmon showed little aggression toward the steelhead. Cortisol concentrations were significantly higher for chinook salmon in tanks receiving steelhead than in tanks receiving additional chinook salmon or no additional fish after 2 h (in one of the two experimental runs) and after 32 h (in both experimental runs; combined data). These results suggest that confining steelhead and chinook salmon together, such as in raceways and barges in the Columbia River system and in other situations, is stressful to the chinook salmon. Close

• 2. [Article] A comparison of the behavior and survival of juvenile coho salmon (Oncorhynchus kisutch) and steelhead trout (O. mykiss) in a small estuary system

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors ...

  Citation × Citation Citation Abstract Copy Title: A comparison of the behavior and survival of juvenile coho salmon (Oncorhynchus kisutch) and steelhead trout (O. mykiss) in a small estuary system Author: Schreck, Carl B., Stahl, Thomas, Clements, Shaun This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: A comparison of the behavior and survival of juvenile coho salmon (Oncorhynchus kisutch) and steelhead trout (O. mykiss) in a small estuary system Author: Schreck, Carl B., Stahl, Thomas, Clements, Shaun This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/aquaculture/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 3. [Article] Innate and adaptive immune responses in migrating spring-run adult chinook salmon, Oncorhynchus tshawytscha

  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 published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Innate and adaptive immune responses in migrating spring-run adult chinook salmon, Oncorhynchus tshawytscha Author: Schreck, Carl B., Kent, Michael L., Dolan, Brian P., Colvin, Michael E., Fisher, Kathleen M., Benda, Susan E., Peterson, James T. 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 published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/fish-and-shellfish-immunology/ Title: Innate and adaptive immune responses in migrating spring-run adult chinook salmon, Oncorhynchus tshawytscha Author: Schreck, Carl B., Kent, Michael L., Dolan, Brian P., Colvin, Michael E., Fisher, Kathleen M., Benda, Susan E., Peterson, James T. 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 published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/fish-and-shellfish-immunology/ Close

• 4. [Article] Sensitivity and specificity of histology for diagnoses of four common pathogens and detection of nontarget pathogens in adult Chinook salmon (Oncorhynchus tshawytscha) in fresh water

  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 published article is copyrighted by Sage and ...

  Citation × Citation Citation Abstract Copy Title: Sensitivity and specificity of histology for diagnoses of four common pathogens and detection of nontarget pathogens in adult Chinook salmon (Oncorhynchus tshawytscha) in fresh water Author: Schreck, Carl B., St-Hilaire, Sophie, Benda, Susan, Kent, Michael L. 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 published article is copyrighted by Sage and can be found at: http://www.sagepub.com/home.nav. Title: Sensitivity and specificity of histology for diagnoses of four common pathogens and detection of nontarget pathogens in adult Chinook salmon (Oncorhynchus tshawytscha) in fresh water Author: Schreck, Carl B., St-Hilaire, Sophie, Benda, Susan, Kent, Michael L. 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 published article is copyrighted by Sage and can be found at: http://www.sagepub.com/home.nav. Close

• 5. [Article] Effects of routine handling and tagging procedures on physiological stress responses in juvenile chinook salmon

  Juvenile chinook salmon Oncorhynchus tshawytscha were subjected to handling and tagging protocols typical of normal hatchery operations and monitored for their physiological response to stress. Treatments ...

  Citation × Citation Citation Abstract Copy Title: Effects of routine handling and tagging procedures on physiological stress responses in juvenile chinook salmon Author: Schreck, Carl B., Sharpe, Cameron S., Thompson, Daniel A., Blankenship, H. Lee Juvenile chinook salmon Oncorhynchus tshawytscha were subjected to handling and tagging protocols typical of normal hatchery operations and monitored for their physiological response to stress. Treatments included coded-wire-tagging, counting, ventral fin clipping, adipose fin clipping, and a procedure simulating a pond split. Treatment fish were also subjected to a standardized stress challenge (1 h confinement) to evaluate their ability to deal with disturbances subsequent to a handling or tagging procedure. Circulating levels of cortisol and glucose were used as indicators of stress. Each of the treatments elicited very similar responses among treatment groups. Cortisol increased from resting levels of about 20 ng/mL to about 90 ng/mL by 1 h poststress and returned to near resting levels by 8 h poststress. Glucose levels increased from 50 mg/dL to about 80 mg/dL by 1 h poststress and remained elevated for much of the experiment. The cortisol and glucose responses to the confinement stress did not differ over time or among treatments. However, the confinement stress results do suggest a small but significant cumulative response, indicating small residual effects of the original handling protocols. No deaths were noted among treatment groups. Title: Effects of routine handling and tagging procedures on physiological stress responses in juvenile chinook salmon Author: Schreck, Carl B., Sharpe, Cameron S., Thompson, Daniel A., Blankenship, H. Lee Juvenile chinook salmon Oncorhynchus tshawytscha were subjected to handling and tagging protocols typical of normal hatchery operations and monitored for their physiological response to stress. Treatments included coded-wire-tagging, counting, ventral fin clipping, adipose fin clipping, and a procedure simulating a pond split. Treatment fish were also subjected to a standardized stress challenge (1 h confinement) to evaluate their ability to deal with disturbances subsequent to a handling or tagging procedure. Circulating levels of cortisol and glucose were used as indicators of stress. Each of the treatments elicited very similar responses among treatment groups. Cortisol increased from resting levels of about 20 ng/mL to about 90 ng/mL by 1 h poststress and returned to near resting levels by 8 h poststress. Glucose levels increased from 50 mg/dL to about 80 mg/dL by 1 h poststress and remained elevated for much of the experiment. The cortisol and glucose responses to the confinement stress did not differ over time or among treatments. However, the confinement stress results do suggest a small but significant cumulative response, indicating small residual effects of the original handling protocols. No deaths were noted among treatment groups. Close

• 6. [Article] Comparison of Predator Avoidance Capabilities with Corticosteroid Levels Induced by Stress in Juvenile Coho Salmon

  The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of ...

  Citation × Citation Citation Abstract Copy Title: Comparison of Predator Avoidance Capabilities with Corticosteroid Levels Induced by Stress in Juvenile Coho Salmon Author: Schreck, Carl B., Olla, Bori L., Davis, Michael W. The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of fish were held out of water for 1 min, then allowed to recover from this stress for 1, 90, or 240 min. After each recovery period, some unstressed and stressed fish were sampled for plasma cortisol, and others were subjected to predation by lingcod Ophiodon elongatus. Levels of corticosteroids in stressed fish remained high throughout the 240-min period of recovery, but predator avoidance returned to control levels in less than 90 min. Results suggest that juvenile coho salmon quickly recover basic survival skills of predator avoidance after mild stress, even though cortisol levels continue to indicate a stressed condition. Title: Comparison of Predator Avoidance Capabilities with Corticosteroid Levels Induced by Stress in Juvenile Coho Salmon Author: Schreck, Carl B., Olla, Bori L., Davis, Michael W. The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of fish were held out of water for 1 min, then allowed to recover from this stress for 1, 90, or 240 min. After each recovery period, some unstressed and stressed fish were sampled for plasma cortisol, and others were subjected to predation by lingcod Ophiodon elongatus. Levels of corticosteroids in stressed fish remained high throughout the 240-min period of recovery, but predator avoidance returned to control levels in less than 90 min. Results suggest that juvenile coho salmon quickly recover basic survival skills of predator avoidance after mild stress, even though cortisol levels continue to indicate a stressed condition. Close

• 7. [Article] KentMichael.Microbiology.ImpactsMultispeciesParasitism.pdf

  Citation × Citation Citation Abstract Copy Title: KentMichael.Microbiology.ImpactsMultispeciesParasitism.pdf Author: Schreck, Carl B., Glynn, Michael, Ferguson, Jayde, Kent, Michael L., Sifneos, Jean C., Romer, Jeremy, Madsen, Lisa Title: KentMichael.Microbiology.ImpactsMultispeciesParasitism.pdf Author: Schreck, Carl B., Glynn, Michael, Ferguson, Jayde, Kent, Michael L., Sifneos, Jean C., Romer, Jeremy, Madsen, Lisa Close

• 8. [Article] KentMichaelMicrobiologyImpactsMultispeciesParasitismFullText.pdf

  Citation × Citation Citation Abstract Copy Title: KentMichaelMicrobiologyImpactsMultispeciesParasitismFullText.pdf Author: Schreck, Carl B., Glynn, Michael, Ferguson, Jayde, Kent, Michael L., Sifneos, Jean C., Romer, Jeremy, Madsen, Lisa Title: KentMichaelMicrobiologyImpactsMultispeciesParasitismFullText.pdf Author: Schreck, Carl B., Glynn, Michael, Ferguson, Jayde, Kent, Michael L., Sifneos, Jean C., Romer, Jeremy, Madsen, Lisa Close

• 9. [Article] Cool, Pathogen-Free Refuge Lowers Pathogen-Associated Prespawn Mortality of Willamette River Chinook Salmon

  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: Cool, Pathogen-Free Refuge Lowers Pathogen-Associated Prespawn Mortality of Willamette River Chinook Salmon Author: Schreck, Carl B., Naughton, George P., Caudill, Christopher C., Benda, Susan E., Kent, Michael L. 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: Cool, Pathogen-Free Refuge Lowers Pathogen-Associated Prespawn Mortality of Willamette River Chinook Salmon Author: Schreck, Carl B., Naughton, George P., Caudill, Christopher C., Benda, Susan E., Kent, Michael L. 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

• 10. [Article] Impacts of Multispecies Parasitism on Juvenile Coho Salmon (Oncorhynchus kisutch) in Oregon

  NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/nGB6XD

  Citation × Citation Citation Abstract Copy Title: Impacts of Multispecies Parasitism on Juvenile Coho Salmon (Oncorhynchus kisutch) in Oregon Author: Schreck, Carl B., Glynn, Michael, Ferguson, Jayde, Kent, Michael L., Sifneos, Jean C., Romer, Jeremy, Madsen, Lisa NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/nGB6XD Title: Impacts of Multispecies Parasitism on Juvenile Coho Salmon (Oncorhynchus kisutch) in Oregon Author: Schreck, Carl B., Glynn, Michael, Ferguson, Jayde, Kent, Michael L., Sifneos, Jean C., Romer, Jeremy, Madsen, Lisa NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/nGB6XD Close