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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] Stream habitat utilization and behavior of sympatric and allopatric wild cutthroat trout (Salmo clarki) and hatchery coho salmon (Oncorhynchus kitsutch)

  The behavior and stream habitat utilization of juvenile hatchery-reared coho salmon (Ovicozihynchus kisutch) and wild cutthroat trout (Salmo clarki) were examined to assess the nature of interactions between ...

  Citation × Citation Citation Abstract Copy Title: Stream habitat utilization and behavior of sympatric and allopatric wild cutthroat trout (Salmo clarki) and hatchery coho salmon (Oncorhynchus kitsutch) Author: Jacobs, Steven Edward The behavior and stream habitat utilization of juvenile hatchery-reared coho salmon (Ovicozihynchus kisutch) and wild cutthroat trout (Salmo clarki) were examined to assess the nature of interactions between the species potentially resulting from introductions of hatchery coho salmon in streams. Habitat utilization was monitored in Mill Creek, Polk Co., Oregon by manipulating the composition of fish within three study sections to include either allopatric or sympatric populations of hatchery coho salmon and wild cutthroat trout. In allopatry, coho salmon and cutthroat trout selected feeding microhabitat that was similar in physical characteristics and exhibited extensive dietary overlap. When the two species occurred in sympatry, feeding microhabitat used by coho salmon was altered, however, that of cutthroat trout was comparable to allopatric cutthroat trout. No discernable differences in dietary composition between allopatric and sympatric fish were detected. While allopatric cutthroat trout always gained mass. ailopatric coho salmon always lost mass. Stomach fullness indices were higher for allopatric cutthroat trout than allopatric coho salmon. Sympatric cutthroat trout had comparable or greater gains of mass, indices of stomach fullness, and hepatic glycogen reserves relative to allopatric cutthroat trout. Conversely, sympatric coho salmon had greater losses of mass, reduced hepatic glycogen reserves, and apparently lower indices of stomach fullness than allopatric salmon. Behavioral observations made through the use of an in-stream viewing chamber in Berry Creek, Benton Co., Oregon, indicated that in allopatry populations of hatchery coho salmon and wild cutthroat trout were structured as linear dominance hierarchies that were organized by quantitatively and qualitatively similar aggressive interactions. In sympatry, however, cutthroat trout were more aggressive and socially dominant to coho salmon. The shift in use of micro-habitat and reduction in habitat utilization effectiveness of hatchery coho salmon in the presence of cutthroat trout can, thus, be interpreted to occur as a result of interference competition mediated through interspecific aggression. Title: Stream habitat utilization and behavior of sympatric and allopatric wild cutthroat trout (Salmo clarki) and hatchery coho salmon (Oncorhynchus kitsutch) Author: Jacobs, Steven Edward The behavior and stream habitat utilization of juvenile hatchery-reared coho salmon (Ovicozihynchus kisutch) and wild cutthroat trout (Salmo clarki) were examined to assess the nature of interactions between the species potentially resulting from introductions of hatchery coho salmon in streams. Habitat utilization was monitored in Mill Creek, Polk Co., Oregon by manipulating the composition of fish within three study sections to include either allopatric or sympatric populations of hatchery coho salmon and wild cutthroat trout. In allopatry, coho salmon and cutthroat trout selected feeding microhabitat that was similar in physical characteristics and exhibited extensive dietary overlap. When the two species occurred in sympatry, feeding microhabitat used by coho salmon was altered, however, that of cutthroat trout was comparable to allopatric cutthroat trout. No discernable differences in dietary composition between allopatric and sympatric fish were detected. While allopatric cutthroat trout always gained mass. ailopatric coho salmon always lost mass. Stomach fullness indices were higher for allopatric cutthroat trout than allopatric coho salmon. Sympatric cutthroat trout had comparable or greater gains of mass, indices of stomach fullness, and hepatic glycogen reserves relative to allopatric cutthroat trout. Conversely, sympatric coho salmon had greater losses of mass, reduced hepatic glycogen reserves, and apparently lower indices of stomach fullness than allopatric salmon. Behavioral observations made through the use of an in-stream viewing chamber in Berry Creek, Benton Co., Oregon, indicated that in allopatry populations of hatchery coho salmon and wild cutthroat trout were structured as linear dominance hierarchies that were organized by quantitatively and qualitatively similar aggressive interactions. In sympatry, however, cutthroat trout were more aggressive and socially dominant to coho salmon. The shift in use of micro-habitat and reduction in habitat utilization effectiveness of hatchery coho salmon in the presence of cutthroat trout can, thus, be interpreted to occur as a result of interference competition mediated through interspecific aggression. Close

• 5. [Article] Oregon coastal salmon spawning surveys and straying of private hatchery coho salmon from Yaquina and Coos bays

  In addition to standard spawning surveys for coho salmon, this report contains additional sampling in the Yaquina River, at the Salmon River Hatchery and tributaries of Coos Bay "to document straying of ...

  Citation × Citation Citation Abstract Copy Title: Oregon coastal salmon spawning surveys and straying of private hatchery coho salmon from Yaquina and Coos bays Author: Oregon. Dept. of Fish and Wildlife. Research and Development Section, McGie, Alan M. In addition to standard spawning surveys for coho salmon, this report contains additional sampling in the Yaquina River, at the Salmon River Hatchery and tributaries of Coos Bay "to document straying of private hatchery coho salmon from the Oregon Aqua-Foods (OAF) facility at South Beach, Yaquina Bay, and Anadromous, Inc., facility on North Spit, Coos Bay." (from the Introduction, p.2) Title: Oregon coastal salmon spawning surveys and straying of private hatchery coho salmon from Yaquina and Coos bays Author: Oregon. Dept. of Fish and Wildlife. Research and Development Section, McGie, Alan M. In addition to standard spawning surveys for coho salmon, this report contains additional sampling in the Yaquina River, at the Salmon River Hatchery and tributaries of Coos Bay "to document straying of private hatchery coho salmon from the Oregon Aqua-Foods (OAF) facility at South Beach, Yaquina Bay, and Anadromous, Inc., facility on North Spit, Coos Bay." (from the Introduction, p.2) Close

• 6. [Article] The impact of Oregon Aqua-Foods operation on the wild coho salmon in the Yaquina River

  17 p.

  Citation × Citation Citation Abstract Copy Title: The impact of Oregon Aqua-Foods operation on the wild coho salmon in the Yaquina River Author: Oregon. Dept. of Fish and Wildlife. Fish Division 17 p. Title: The impact of Oregon Aqua-Foods operation on the wild coho salmon in the Yaquina River Author: Oregon. Dept. of Fish and Wildlife. Fish Division 17 p. Close

• 7. [Article] Influence of dissolved oxygen concentration and swimming velocity on food consumption and growth of juvenile Coho salmon

  Laboratory studies were conducted on the food consumption, growth, and bioenergetics of juvenile coho salmon (Oncoynchus kisutch) held at various swimming velocities and dissolved oxygen concentrations ...

  Citation × Citation Citation Abstract Copy Title: Influence of dissolved oxygen concentration and swimming velocity on food consumption and growth of juvenile Coho salmon Author: Hutchins, Floyd E. Laboratory studies were conducted on the food consumption, growth, and bioenergetics of juvenile coho salmon (Oncoynchus kisutch) held at various swimming velocities and dissolved oxygen concentrations at 15 C. Food consumption and growth of salmon fed to repletion on housefly larvae (Mus domesticus) were reduced by increasing activity at and above 3 lengths per second (L/sec) and 2 L/sec, respectively. Food conversion efficiencies for growth decreased with increasing activity; efficiencies of converting food to growth and activity combined, however, increased with increasing activity. The logarithm of the rate of energy loss of unfed swimming salmon increased exponentially with increasing velocity. The growth rates of salmon fed to repletion and held at 1.3 and 3.0 L/sec at an oxygen level of 3 mg/liter were reduced by 20 and 65 percent from that of control salmon held at respective velocities in air-saturated water. At the intermediate oxygen concentration of 5 mg/liter, growth rates of salmon were reduced by 0 and 15 percent over controls held at 1.3 and 3.0 L/sec, respectively. The total respiration rate (TRR) of salmon fed to repletion and held at air saturation remained nearly constant over the range of activity levels tested (0 to 3.8 L/sec). At 1.3 L/sec the TRR of salmon increased with increasing food consumption, while at 3.7 L/sec increased food consumption did not alter the TRR. Reduction in oxygen concentration lowered the TRR of salmon, although growth was not reduced in every case. The specific dynamic action of food (SDA), i.e., cost of food digestion and processing, ranged from 10 to 30 percent of the assimilated energy. The larger percentages were observed at high oxygen concentrations, generally at low food consumption rates, and at low velocities; and the lower percentages at low oxygen levels, high food consumption rates, and high velocities. The absolute value of SDA increased with increasing food consumption at 1.3 L/sec, but declined at 3.7 L/sec. In salmon fed to repletion, the SDA decreased with increased activity levels and reduced oxygen concentration. Title: Influence of dissolved oxygen concentration and swimming velocity on food consumption and growth of juvenile Coho salmon Author: Hutchins, Floyd E. Laboratory studies were conducted on the food consumption, growth, and bioenergetics of juvenile coho salmon (Oncoynchus kisutch) held at various swimming velocities and dissolved oxygen concentrations at 15 C. Food consumption and growth of salmon fed to repletion on housefly larvae (Mus domesticus) were reduced by increasing activity at and above 3 lengths per second (L/sec) and 2 L/sec, respectively. Food conversion efficiencies for growth decreased with increasing activity; efficiencies of converting food to growth and activity combined, however, increased with increasing activity. The logarithm of the rate of energy loss of unfed swimming salmon increased exponentially with increasing velocity. The growth rates of salmon fed to repletion and held at 1.3 and 3.0 L/sec at an oxygen level of 3 mg/liter were reduced by 20 and 65 percent from that of control salmon held at respective velocities in air-saturated water. At the intermediate oxygen concentration of 5 mg/liter, growth rates of salmon were reduced by 0 and 15 percent over controls held at 1.3 and 3.0 L/sec, respectively. The total respiration rate (TRR) of salmon fed to repletion and held at air saturation remained nearly constant over the range of activity levels tested (0 to 3.8 L/sec). At 1.3 L/sec the TRR of salmon increased with increasing food consumption, while at 3.7 L/sec increased food consumption did not alter the TRR. Reduction in oxygen concentration lowered the TRR of salmon, although growth was not reduced in every case. The specific dynamic action of food (SDA), i.e., cost of food digestion and processing, ranged from 10 to 30 percent of the assimilated energy. The larger percentages were observed at high oxygen concentrations, generally at low food consumption rates, and at low velocities; and the lower percentages at low oxygen levels, high food consumption rates, and high velocities. The absolute value of SDA increased with increasing food consumption at 1.3 L/sec, but declined at 3.7 L/sec. In salmon fed to repletion, the SDA decreased with increased activity levels and reduced oxygen concentration. Close

• 8. [Article] Hematology and histopathology of Coho salmon (Oncorhynchus kisutch) infected with Flexibacter psychrophilus

  Citation × Citation Citation Abstract Copy Title: Hematology and histopathology of Coho salmon (Oncorhynchus kisutch) infected with Flexibacter psychrophilus Author: Kanchanakhan, Somkiat Title: Hematology and histopathology of Coho salmon (Oncorhynchus kisutch) infected with Flexibacter psychrophilus Author: Kanchanakhan, Somkiat Close

• 9. [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

• 10. [Article] Effects of chlorinated biologically stabilized kraft mill effluent on the mortality and growth of Coho salmon

  Ninety-six hour acute toxicity bioassays were employed to determine the tolerance of juvenile coho salmon to chlorinated stabilized kraft mill effluent (SKME). In addition the effect of chlorinated SKME ...

  Citation × Citation Citation Abstract Copy Title: Effects of chlorinated biologically stabilized kraft mill effluent on the mortality and growth of Coho salmon Author: Steil, Deborah L. Ninety-six hour acute toxicity bioassays were employed to determine the tolerance of juvenile coho salmon to chlorinated stabilized kraft mill effluent (SKME). In addition the effect of chlorinated SKME on the growth of juvenile coho salmon in six and ten day experiments was studied. Results of the acute toxicity tests indicated that the addition of as low as 1 mg/l of total residual chlorine to 100 percent SKME could cause acute toxicity in effluent concentrations as low as 18 percent. Since the non-chlorinated SKME used in these tests was not acutely toxic to the salmon, it appeared that chlorine or some chlorinated material formed in the chlorinated SKME was responsible or the cases of acute toxicity. Effects of chlorinated SKME on the growth of the coho salmon were not clearly defined at the ch1oriie and SKME concentrations tested. Title: Effects of chlorinated biologically stabilized kraft mill effluent on the mortality and growth of Coho salmon Author: Steil, Deborah L. Ninety-six hour acute toxicity bioassays were employed to determine the tolerance of juvenile coho salmon to chlorinated stabilized kraft mill effluent (SKME). In addition the effect of chlorinated SKME on the growth of juvenile coho salmon in six and ten day experiments was studied. Results of the acute toxicity tests indicated that the addition of as low as 1 mg/l of total residual chlorine to 100 percent SKME could cause acute toxicity in effluent concentrations as low as 18 percent. Since the non-chlorinated SKME used in these tests was not acutely toxic to the salmon, it appeared that chlorine or some chlorinated material formed in the chlorinated SKME was responsible or the cases of acute toxicity. Effects of chlorinated SKME on the growth of the coho salmon were not clearly defined at the ch1oriie and SKME concentrations tested. Close