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• 1. [Article] Trophically transmitted parasites as ecosystem indicators : relationships among parasite community structure, juvenile salmon diet composition, and ocean conditions

  Recent research conducted throughout the Northern California Current (NCC) on the ecology of Pacific salmon (Oncorhynchus spp.) indicates that variable ocean conditions affect the community composition ...

  Citation × Citation Citation Abstract Copy Title: Trophically transmitted parasites as ecosystem indicators : relationships among parasite community structure, juvenile salmon diet composition, and ocean conditions Author: Losee, James P. Recent research conducted throughout the Northern California Current (NCC) on the ecology of Pacific salmon (Oncorhynchus spp.) indicates that variable ocean conditions affect the community composition of zooplankton in the nearshore environment which, in turn, can affect the quality of prey for fish, sea birds and mammals. Interannual variability in the quality and composition of the copepod community in the NCC during early marine residency of some Pacific salmon populations is related to survival to adulthood. However, copepods make up a small portion of the diet of coho and Chinook salmon, and the mechanistic linkages between ocean climate, zooplankton composition and salmon prey remain unclear. Parasite analysis provides a supplement to traditional diet analysis that can describe the foraging history of a host species. Coho salmon (O. kisutch) and Chinook salmon (O. tshawytscha) serve as hosts to an array of marine parasites acquired through consumption of infected intermediate hosts such as copepods, euphausiids, and planktivorous fishes. Causing little or no harm to their salmon host, the presence of trophically transmitted parasites provides information on the dietary history of their salmonid host beyond the 24 hours associated with traditional diet analysis. This study (1) examined differences in feeding behavior of coho and Chinook salmon during their early marine residency using both stomach and parasite community analyses and (2) tested the hypothesis that variability in ocean circulation patterns (measured through the Pacific Decadal Oscillation, sea surface temperature (SST) and Bakun's upwelling index) and copepod species composition are related to variability in the community structure of trophically transmitted marine parasites found in juvenile salmon. I compared the abundance and species composition of parasites recovered from juvenile Columbia River coho and upper Columbia River summer and fall Chinook salmon captured off the coast of Washington from 2002 to 2009. I also compared interannual variability in parasite assemblages to physical and biological indices of ocean conditions. Coho and Chinook salmon consumed similar prey taxa; however, the species richness and abundance of trophically transmitted parasites indicated that Chinook salmon consumed a greater diversity and abundance of infected prey. In addition, differences in the abundance of fish in the diet and Anisakis simplex, a parasitic nematode known to infect salmon through fish consumption, suggest that Chinook salmon consistently consumed more fish prey than coho. In contrast, coho appeared to consume more euphausiids as indicated by stomach content analysis and increased abundance of the euphausiid parasite, Rhadinorhynchus trachuri. Shifts in the parasite community composition of both coho and Chinook salmon were related to interannual variability in SST and the biomass of southern-origin copepods (r > 0.7, P < 0.05). The acanthocephalan R. trachuri and a tetraphyllid cestode were associated with "warm" SSTs and greater biomass of lipid-poor, subtropical copepods while the nematode A. simplex was more abundant in years of "cold" SST and a relatively low biomass of subtropical copepods. These results provide novel insight into differences in the diet of Columbia River coho and Chinook salmon and illustrate linkages between ocean climate, zooplankton community composition and salmon diet during early marine residency. Title: Trophically transmitted parasites as ecosystem indicators : relationships among parasite community structure, juvenile salmon diet composition, and ocean conditions Author: Losee, James P. Recent research conducted throughout the Northern California Current (NCC) on the ecology of Pacific salmon (Oncorhynchus spp.) indicates that variable ocean conditions affect the community composition of zooplankton in the nearshore environment which, in turn, can affect the quality of prey for fish, sea birds and mammals. Interannual variability in the quality and composition of the copepod community in the NCC during early marine residency of some Pacific salmon populations is related to survival to adulthood. However, copepods make up a small portion of the diet of coho and Chinook salmon, and the mechanistic linkages between ocean climate, zooplankton composition and salmon prey remain unclear. Parasite analysis provides a supplement to traditional diet analysis that can describe the foraging history of a host species. Coho salmon (O. kisutch) and Chinook salmon (O. tshawytscha) serve as hosts to an array of marine parasites acquired through consumption of infected intermediate hosts such as copepods, euphausiids, and planktivorous fishes. Causing little or no harm to their salmon host, the presence of trophically transmitted parasites provides information on the dietary history of their salmonid host beyond the 24 hours associated with traditional diet analysis. This study (1) examined differences in feeding behavior of coho and Chinook salmon during their early marine residency using both stomach and parasite community analyses and (2) tested the hypothesis that variability in ocean circulation patterns (measured through the Pacific Decadal Oscillation, sea surface temperature (SST) and Bakun's upwelling index) and copepod species composition are related to variability in the community structure of trophically transmitted marine parasites found in juvenile salmon. I compared the abundance and species composition of parasites recovered from juvenile Columbia River coho and upper Columbia River summer and fall Chinook salmon captured off the coast of Washington from 2002 to 2009. I also compared interannual variability in parasite assemblages to physical and biological indices of ocean conditions. Coho and Chinook salmon consumed similar prey taxa; however, the species richness and abundance of trophically transmitted parasites indicated that Chinook salmon consumed a greater diversity and abundance of infected prey. In addition, differences in the abundance of fish in the diet and Anisakis simplex, a parasitic nematode known to infect salmon through fish consumption, suggest that Chinook salmon consistently consumed more fish prey than coho. In contrast, coho appeared to consume more euphausiids as indicated by stomach content analysis and increased abundance of the euphausiid parasite, Rhadinorhynchus trachuri. Shifts in the parasite community composition of both coho and Chinook salmon were related to interannual variability in SST and the biomass of southern-origin copepods (r > 0.7, P < 0.05). The acanthocephalan R. trachuri and a tetraphyllid cestode were associated with "warm" SSTs and greater biomass of lipid-poor, subtropical copepods while the nematode A. simplex was more abundant in years of "cold" SST and a relatively low biomass of subtropical copepods. These results provide novel insight into differences in the diet of Columbia River coho and Chinook salmon and illustrate linkages between ocean climate, zooplankton community composition and salmon diet during early marine residency. Close

• 2. [Article] 1979 status report for ocean salmon fisheries off Oregon.

  This report summarizes the 1979 ocean salmon fishing season off the Oregon coast. Troll fishery landings were obtained directly from commercial fish receiving tickets supplemented with a survey of fish ...

  Citation × Citation Citation Abstract Copy Title: 1979 status report for ocean salmon fisheries off Oregon. Author: Oregon Dept. of Fish and Wildlife. Ocean Salmon Management. This report summarizes the 1979 ocean salmon fishing season off the Oregon coast. Troll fishery landings were obtained directly from commercial fish receiving tickets supplemented with a survey of fish buyers to obtain the most up-to-date estimate of total landings. Recreational catch and effort were obtained from creel census survey at coastal ports by ODFW personnel. Recreational catch and effort information is included for the period May 12 through September 16 while commercial troll landings encompass the period from May 1 through November 13. Title: 1979 status report for ocean salmon fisheries off Oregon. Author: Oregon Dept. of Fish and Wildlife. Ocean Salmon Management. This report summarizes the 1979 ocean salmon fishing season off the Oregon coast. Troll fishery landings were obtained directly from commercial fish receiving tickets supplemented with a survey of fish buyers to obtain the most up-to-date estimate of total landings. Recreational catch and effort were obtained from creel census survey at coastal ports by ODFW personnel. Recreational catch and effort information is included for the period May 12 through September 16 while commercial troll landings encompass the period from May 1 through November 13. Close

• 3. [Article] The effects of single and multiple pathogen and parasite infections on juvenile chinook and coho salmon during early marine residency

  Nearly 3000 juvenile Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon captured in nearshore waters off the coasts of Washington and Oregon from 1999-2004 were tested for infection by Renibacterium ...

  Citation × Citation Citation Abstract Copy Title: The effects of single and multiple pathogen and parasite infections on juvenile chinook and coho salmon during early marine residency Author: Sandell, Todd A. Nearly 3000 juvenile Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon captured in nearshore waters off the coasts of Washington and Oregon from 1999-2004 were tested for infection by Renibacterium salmoninarum, Nanophyetus salmincola, and skin metacercariae. First, three quantitative PCR primer/probe sets were compared for detection of R. salmoninarum; amplification of the single copy abc gene was best at detecting medium-high levels of infection and was used in subsequent studies. Parasite infections were detected visually. Infection by N. salmincola was the most common single infection among all juvenile salmon (55.2%), followed by R. salmoninarum (27.5%) and skin metacercariae (16.5%). Infection by R. salmoninarum was highest in 2000, with 54.8% of all juvenile salmon infected, and was much lower in 2004 (<10%). Subyearling (but not yearling) Chinook salmon infected by N. salmincola had significantly reduced growth; skin metacercarial infection was associated with significantly reduced growth only for coho salmon. Infection by R. salmoninarum was associated with significantly reduced growth in yearling Chinook salmon and coho salmon. Multiple infections did not have significantly more severe effects on growth than single infections, although the prevalence of triple infections was very low. The prevalence of R. salmoninarum was significantly and positively correlated with increased survival for both yearling Chinook and coho salmon. To better understand the apparent paradox that higher prevalences correlate with increased survival, we examined the effects of ocean conditions using the summer Pacific Decadal Oscillation (PDO) index as an indicator of good (cold) or bad (warm) ocean condition years. The years 1999-2002 were cold ocean years, and 2003-2004 were warm ocean years. The prevalence of R. salmoninarum was significantly higher in cold years, when ocean conditions were favorable, and more salmon with severe infections were captured; there was no effect of infection on growth. In the summers of warm years, infected yearling Chinook and coho salmon had significantly reduced growth, and the prevalence and severity of R. salmoninarum infections declined. These data indicate that the infection is less detrimental in years with favorable ocean conditions, and suggest that R. salmoninarum infection may be a mechanism linking ocean indices to salmon survival. Title: The effects of single and multiple pathogen and parasite infections on juvenile chinook and coho salmon during early marine residency Author: Sandell, Todd A. Nearly 3000 juvenile Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon captured in nearshore waters off the coasts of Washington and Oregon from 1999-2004 were tested for infection by Renibacterium salmoninarum, Nanophyetus salmincola, and skin metacercariae. First, three quantitative PCR primer/probe sets were compared for detection of R. salmoninarum; amplification of the single copy abc gene was best at detecting medium-high levels of infection and was used in subsequent studies. Parasite infections were detected visually. Infection by N. salmincola was the most common single infection among all juvenile salmon (55.2%), followed by R. salmoninarum (27.5%) and skin metacercariae (16.5%). Infection by R. salmoninarum was highest in 2000, with 54.8% of all juvenile salmon infected, and was much lower in 2004 (<10%). Subyearling (but not yearling) Chinook salmon infected by N. salmincola had significantly reduced growth; skin metacercarial infection was associated with significantly reduced growth only for coho salmon. Infection by R. salmoninarum was associated with significantly reduced growth in yearling Chinook salmon and coho salmon. Multiple infections did not have significantly more severe effects on growth than single infections, although the prevalence of triple infections was very low. The prevalence of R. salmoninarum was significantly and positively correlated with increased survival for both yearling Chinook and coho salmon. To better understand the apparent paradox that higher prevalences correlate with increased survival, we examined the effects of ocean conditions using the summer Pacific Decadal Oscillation (PDO) index as an indicator of good (cold) or bad (warm) ocean condition years. The years 1999-2002 were cold ocean years, and 2003-2004 were warm ocean years. The prevalence of R. salmoninarum was significantly higher in cold years, when ocean conditions were favorable, and more salmon with severe infections were captured; there was no effect of infection on growth. In the summers of warm years, infected yearling Chinook and coho salmon had significantly reduced growth, and the prevalence and severity of R. salmoninarum infections declined. These data indicate that the infection is less detrimental in years with favorable ocean conditions, and suggest that R. salmoninarum infection may be a mechanism linking ocean indices to salmon survival. Close

• 4. [Article] Management of the Ocean Salmon Fishery. Annual Report: October 1, 1978 to September 30, 1979.

  This report summarizes the activities pursued by the Ocean Salmon Management Program during FY 1979, as well as listing regulation changes. The report also provides statistics for recreational Chinook ...

  Citation × Citation Citation Abstract Copy Title: Management of the Ocean Salmon Fishery. Annual Report: October 1, 1978 to September 30, 1979. Author: McQueen, Robert K., Loomis, David W. This report summarizes the activities pursued by the Ocean Salmon Management Program during FY 1979, as well as listing regulation changes. The report also provides statistics for recreational Chinook and Coho catches such as age composition and average weight. Sponsored by the U.S. Department of Commerce under the Anadromous Fisheries Act: Project Number: AFC-75-3 Contract Number: 9-ABD0RIB You might also check out Management of the troll salmon fishery: annual report; 1977/1978: http://hdl.handle.net/1957/55886 Title: Management of the Ocean Salmon Fishery. Annual Report: October 1, 1978 to September 30, 1979. Author: McQueen, Robert K., Loomis, David W. This report summarizes the activities pursued by the Ocean Salmon Management Program during FY 1979, as well as listing regulation changes. The report also provides statistics for recreational Chinook and Coho catches such as age composition and average weight. Sponsored by the U.S. Department of Commerce under the Anadromous Fisheries Act: Project Number: AFC-75-3 Contract Number: 9-ABD0RIB You might also check out Management of the troll salmon fishery: annual report; 1977/1978: http://hdl.handle.net/1957/55886 Close

• 5. [Article] Spawning Coho and Chinook Salmon Surveys in Coastal Watersheds of Oregon, 1976

  This document provides the methods and summary of continued surveys on spawning Chinook and Coho salmon in coastal streams of Oregon for 1950-1976.

  Citation × Citation Citation Abstract Copy Title: Spawning Coho and Chinook Salmon Surveys in Coastal Watersheds of Oregon, 1976 Author: Oregon. Department of Fish & Wildlife, Cummings, Ed This document provides the methods and summary of continued surveys on spawning Chinook and Coho salmon in coastal streams of Oregon for 1950-1976. Title: Spawning Coho and Chinook Salmon Surveys in Coastal Watersheds of Oregon, 1976 Author: Oregon. Department of Fish & Wildlife, Cummings, Ed This document provides the methods and summary of continued surveys on spawning Chinook and Coho salmon in coastal streams of Oregon for 1950-1976. Close

• 6. [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

• 7. [Article] Relationship Between Temperature and Ceratomyxa shasta–Induced Mortality In Klamath River Salmonids

  This is the publisher’s final pdf. The published article is copyrighted by American Society of Parasitologists and can be found at: http://amsocparasit.org/.

  Citation × Citation Citation Abstract Copy Title: Relationship Between Temperature and Ceratomyxa shasta–Induced Mortality In Klamath River Salmonids Author: Bartholomew, Jerri L., Holt, Richard A., Ray, R. Adam This is the publisher’s final pdf. The published article is copyrighted by American Society of Parasitologists and can be found at: http://amsocparasit.org/. Title: Relationship Between Temperature and Ceratomyxa shasta–Induced Mortality In Klamath River Salmonids Author: Bartholomew, Jerri L., Holt, Richard A., Ray, R. Adam This is the publisher’s final pdf. The published article is copyrighted by American Society of Parasitologists and can be found at: http://amsocparasit.org/. Close