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• 1. [Article] Ontogenetic shifts in diets of juvenile and subadult coho and chinook salmon in coastal marine waters: important for marine survival?

  Successfully shifting to a more piscivorous diet may be an important factor in the growth and survival of juvenile coho salmon Oncorhynchus kisutch and Chinook salmon O. tshawytscha during their first ...

  Citation × Citation Citation Abstract Copy Title: Ontogenetic shifts in diets of juvenile and subadult coho and chinook salmon in coastal marine waters: important for marine survival? Author: Weitkamp, Laurie A., Brodeur, Richard D., Daly, Elizabeth A. Successfully shifting to a more piscivorous diet may be an important factor in the growth and survival of juvenile coho salmon Oncorhynchus kisutch and Chinook salmon O. tshawytscha during their first summer in the northern California Current. Nonmetric multidimensional scaling and cluster analysis of diets by size showed several distinct groupings as the salmon grew during their first marine summer. These size-based diet differences were clearly driven by increased rates of piscivory for both species. Fish prey composition, feeding intensity, and fish prey-predator length ratios all significantly increased for coho salmon at approximately 240 mm fork length when they changed from diets dominated by juvenile rockfishes Sebastes spp., the larvae of crabs Cancer spp., and adult euphausiids to one of predominantly juvenile forage fish. As Chinook salmon grew, they gradually increased the proportional contribution (by weight) of fish prey in their diets-from 55% in the smallest length-class examined (80-100 mm) to 95% in the largest one (. 375 mm). Chinook salmon fed in the same marine environments as coho salmon and consistently ate more and longer fish prey at a given size than coho salmon but had lower overall feeding intensity, perhaps owing to a higher level of prey selection. Relating subsequent interannual adult salmon returns to juvenile diets showed mixed results. During lower-survival years, coho salmon ate fewer and smaller fish prey, while subyearling Chinook salmon had less total food and more empty stomachs. We did not find consistent trophic patterns for yearling Chinook salmon in relation to their ultimate survival. Title: Ontogenetic shifts in diets of juvenile and subadult coho and chinook salmon in coastal marine waters: important for marine survival? Author: Weitkamp, Laurie A., Brodeur, Richard D., Daly, Elizabeth A. Successfully shifting to a more piscivorous diet may be an important factor in the growth and survival of juvenile coho salmon Oncorhynchus kisutch and Chinook salmon O. tshawytscha during their first summer in the northern California Current. Nonmetric multidimensional scaling and cluster analysis of diets by size showed several distinct groupings as the salmon grew during their first marine summer. These size-based diet differences were clearly driven by increased rates of piscivory for both species. Fish prey composition, feeding intensity, and fish prey-predator length ratios all significantly increased for coho salmon at approximately 240 mm fork length when they changed from diets dominated by juvenile rockfishes Sebastes spp., the larvae of crabs Cancer spp., and adult euphausiids to one of predominantly juvenile forage fish. As Chinook salmon grew, they gradually increased the proportional contribution (by weight) of fish prey in their diets-from 55% in the smallest length-class examined (80-100 mm) to 95% in the largest one (. 375 mm). Chinook salmon fed in the same marine environments as coho salmon and consistently ate more and longer fish prey at a given size than coho salmon but had lower overall feeding intensity, perhaps owing to a higher level of prey selection. Relating subsequent interannual adult salmon returns to juvenile diets showed mixed results. During lower-survival years, coho salmon ate fewer and smaller fish prey, while subyearling Chinook salmon had less total food and more empty stomachs. We did not find consistent trophic patterns for yearling Chinook salmon in relation to their ultimate survival. Close

• 2. [Article] Defining marine habitat of juvenile Chinook salmon, Oncorhynchus tshawytscha, and coho salmon, O. kisutch, in the northern California Current System

  This is the publisher’s final pdf. The published article is copyrighted by Springer Science and can be found at: www.springer.com/.

  Citation × Citation Citation Abstract Copy Title: Defining marine habitat of juvenile Chinook salmon, Oncorhynchus tshawytscha, and coho salmon, O. kisutch, in the northern California Current System Author: Reese, Douglas C., Pool, Suzan S., Brodeur, Richard D. This is the publisher’s final pdf. The published article is copyrighted by Springer Science and can be found at: www.springer.com/. Title: Defining marine habitat of juvenile Chinook salmon, Oncorhynchus tshawytscha, and coho salmon, O. kisutch, in the northern California Current System Author: Reese, Douglas C., Pool, Suzan S., Brodeur, Richard D. This is the publisher’s final pdf. The published article is copyrighted by Springer Science and can be found at: www.springer.com/. Close

• 3. [Article] Winter ichthyoplankton biomass as a predictor of early summer prey fields and survival of juvenile salmon in the northern California Current

  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 Inter-Research ...

  Citation × Citation Citation Abstract Copy Title: Winter ichthyoplankton biomass as a predictor of early summer prey fields and survival of juvenile salmon in the northern California Current Author: Auth, Toby D., Peterson, William T., Daly, Elizabeth A., Brodeur, Richard D. 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 Inter-Research and can be found at: http://www.int-res.com/home/. Title: Winter ichthyoplankton biomass as a predictor of early summer prey fields and survival of juvenile salmon in the northern California Current Author: Auth, Toby D., Peterson, William T., Daly, Elizabeth A., Brodeur, Richard D. 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 Inter-Research and can be found at: http://www.int-res.com/home/. Close

• 4. [Article] Warming Ocean Conditions Relate to Increased Trophic Requirements of Threatened and Endangered 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 was published by the Public Library ...

  Citation × Citation Citation Abstract Copy Title: Warming Ocean Conditions Relate to Increased Trophic Requirements of Threatened and Endangered Salmon Author: Daly, Elizabeth A., Brodeur, Richard D. 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 was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/ Title: Warming Ocean Conditions Relate to Increased Trophic Requirements of Threatened and Endangered Salmon Author: Daly, Elizabeth A., Brodeur, Richard D. 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 was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/ Close

• 5. [Article] Evidence that summer jellyfish blooms impact Pacific Northwest salmon production

  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 the author(s) ...

  Citation × Citation Citation Abstract Copy Title: Evidence that summer jellyfish blooms impact Pacific Northwest salmon production Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. 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 the author(s) and published by Ecological Society of America. The published article can be found at: http://esajournals.onlinelibrary.wiley.com/hub/journal/10.1002/%28ISSN%292150-8925/ Title: Evidence that summer jellyfish blooms impact Pacific Northwest salmon production Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. 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 the author(s) and published by Ecological Society of America. The published article can be found at: http://esajournals.onlinelibrary.wiley.com/hub/journal/10.1002/%28ISSN%292150-8925/ Close

• 6. [Article] RuzickaEvidencethatSummerJellyfish.pdf

  Citation × Citation Citation Abstract Copy Title: RuzickaEvidencethatSummerJellyfish.pdf Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. Title: RuzickaEvidencethatSummerJellyfish.pdf Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. Close

• 7. [Article] RuzickaEvidencethatSummerJellyfishSupplementalTables.pdf

  Citation × Citation Citation Abstract Copy Title: RuzickaEvidencethatSummerJellyfishSupplementalTables.pdf Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. Title: RuzickaEvidencethatSummerJellyfishSupplementalTables.pdf Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. Close

• 8. [Article] RuzickaEvidencethatSummerJellyfishSupplementS1.zip

  Citation × Citation Citation Abstract Copy Title: RuzickaEvidencethatSummerJellyfishSupplementS1.zip Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. Title: RuzickaEvidencethatSummerJellyfishSupplementS1.zip Author: Daly, Elizabeth A., Ruzicka, James J., Brodeur, Richard D. Close

• 9. [Article] Spatial and trophic overlap of marked and unmarked Columbia River Basin spring Chinook salmon during early marine residence with implications for competition between hatchery and naturally produced fish

  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 Springer ...

  Citation × Citation Citation Abstract Copy Title: Spatial and trophic overlap of marked and unmarked Columbia River Basin spring Chinook salmon during early marine residence with implications for competition between hatchery and naturally produced fish Author: Teel, David J., Fisher, Joseph P., Beckman, Brian R., Weitkamp, Laurie A., Brodeur, Richard D., Daly, Elizabeth A. 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 Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Title: Spatial and trophic overlap of marked and unmarked Columbia River Basin spring Chinook salmon during early marine residence with implications for competition between hatchery and naturally produced fish Author: Teel, David J., Fisher, Joseph P., Beckman, Brian R., Weitkamp, Laurie A., Brodeur, Richard D., Daly, Elizabeth A. 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 Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Close

• 10. [Article] Diel Feeding Chronology, Gastric Evacuation, and Daily Food Consumption of Juvenile Chinook Salmon in Oregon Coastal Waters

  The diel feeding periodicity of juvenile Chinook salmon Oncorhynchus tshawytscha was determined from stomachs collected in coastal waters off Oregon in 2000 and 2003. Juvenile Chinook salmon exhibited ...

  Citation × Citation Citation Abstract Copy Title: Diel Feeding Chronology, Gastric Evacuation, and Daily Food Consumption of Juvenile Chinook Salmon in Oregon Coastal Waters Author: Hurst, Thomas P., Daly, Elizabeth A., Benkwitt, Cassandra E., Brodeur, Richard D. The diel feeding periodicity of juvenile Chinook salmon Oncorhynchus tshawytscha was determined from stomachs collected in coastal waters off Oregon in 2000 and 2003. Juvenile Chinook salmon exhibited a diurnal feeding pattern with morning and evening feeding periods. There were differences in the duration and magnitude of the dawn and dusk peaks between the 2 years. Gastric evacuation rates of euphausiid meals were estimated from laboratory experiments at 9.3, 10.7, and 13.9 degree C. Based on an exponential model, the instantaneous evacuation rates at these three temperatures were 0.0407, 0.0589, and 0.0807 per hour, respectively. The daily ration of juvenile Chinook salmon in Oregon coastal waters in 2000 and 2003 was estimated using three models. Using laboratory-derived evacuation rates, the Elliott and Persson and Eggers models produced daily ration estimates of 2.04% and 2.57% of body weight (BW), respectively, in 2000 and 2.93% and 2.46%BW in 2003. The MAXIMS model, which does not rely on laboratory-derived evacuation rates, produced higher estimates of daily ration (3.84% and 4.28%BW). Our diel feeding chronology, gastric evacuation rate, and daily ration estimates for juvenile Chinook salmon were comparable to those of other juvenile salmonids. Title: Diel Feeding Chronology, Gastric Evacuation, and Daily Food Consumption of Juvenile Chinook Salmon in Oregon Coastal Waters Author: Hurst, Thomas P., Daly, Elizabeth A., Benkwitt, Cassandra E., Brodeur, Richard D. The diel feeding periodicity of juvenile Chinook salmon Oncorhynchus tshawytscha was determined from stomachs collected in coastal waters off Oregon in 2000 and 2003. Juvenile Chinook salmon exhibited a diurnal feeding pattern with morning and evening feeding periods. There were differences in the duration and magnitude of the dawn and dusk peaks between the 2 years. Gastric evacuation rates of euphausiid meals were estimated from laboratory experiments at 9.3, 10.7, and 13.9 degree C. Based on an exponential model, the instantaneous evacuation rates at these three temperatures were 0.0407, 0.0589, and 0.0807 per hour, respectively. The daily ration of juvenile Chinook salmon in Oregon coastal waters in 2000 and 2003 was estimated using three models. Using laboratory-derived evacuation rates, the Elliott and Persson and Eggers models produced daily ration estimates of 2.04% and 2.57% of body weight (BW), respectively, in 2000 and 2.93% and 2.46%BW in 2003. The MAXIMS model, which does not rely on laboratory-derived evacuation rates, produced higher estimates of daily ration (3.84% and 4.28%BW). Our diel feeding chronology, gastric evacuation rate, and daily ration estimates for juvenile Chinook salmon were comparable to those of other juvenile salmonids. Close