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• 91. [Article] The 1951 Alsea River silver salmon tagging program

  During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether ...

  Citation × Citation Citation Abstract Copy Title: The 1951 Alsea River silver salmon tagging program Author: Oregon. Fish Commission, Cleaver, Fred C. (Frederick Charles), 1916-, Morgan, Alfred R. During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether tagged fish released in different apparent conditions suffered differential mortalities. Under the hypothesis that the recovery of the fish in the commercial fishery was independent of the apparent condition of the fish when it was released, a significant value of chi-square was obtained. However, it was concluded that this significance was a result of sampling differences and not actually due to differences in mortality. The number of fish taken in the commercial catch each week was calculated by dividing the number of pounds in the weekly catch by the average weight of the fish in the samples for that week. It was calculated that the commercial fishery took approximately 14,000 fish during the season, which was only about 15 per cent of the run available to the fishery. This is an extremely low fishing mortality and is considerably lower than had been expected. The number of tags taken each week by the commercial fishery was calculated by dividing the number of fish in the catch each week by the number of fish per tag in the samples for the week. It was calculated that 67 tags were taken during the season by the commercial fishery. This number of recoveries was 15.5 per cent of the 438 tags available to the fishery. With the cooperation of a number of boat moorages on the Alsea River, an estimate of the sport catch of silver salmon was made. It was calculated that the lower river sport fishery took approximately 3,000 adult silvers with an additional 500 fish being taken by the bank fishery. The weight of the total catch of 3,500 fish was calculated to be about 33,000 pounds. This weight formed 20.2 percent of the combined commercial and sport catches. It was calculated that 18 tagged fish were taken in the sport catch. A total of 44 numbered Petersen and jaw tags were recovered from both dead and live fish which had reached spawning areas. This number includes three tags recovered from the spawning grounds of adjacent streams. When the tagged fish were examined according to areas recovered, it was found that Drift Creek had a smaller number of fish per tag than any other area with one exception. Recoveries appeared to be distributed throughout the drainage from any particular time of tagging. Fish enter the lower river together, then separate to the various spawning areas in the system. Several fish moved from the tagging location in the Alsea River to adjacent streams. About 7 percent of the total recoveries in Table 12 were made from streams other than the Alsea River. The Petersen and jaw tag recoveries in the samples of the commercial catch were examined for selection of the Petersen tags by the nets. The percentage by size group in the catch of fish with each type of tag was about the same as the percentage by size group with each type of tag at the time of release. Large losses of tags in the fishery would have been reflected by a higher number of fish per tag on the spawning grounds. Since the gill-nets did not appear to be selective on either type of tag, the Petersen tags, jaw tags, and tag scars were combined in the calculations involving tag recoveries. After the fish moved beyond the fishing area, many still did not move rapidly to the spawning grounds. Several were taken in tidewater or in the vicinity of tidewater 48-58 days after they had been tagged. The average time between tagging and recovery on the spawning grounds was 63 days for live fish and 70 days for dead fish. Using the method proposed by Schaefer (1951a) for obtaining a population estimate from spawning ground recoveries, an estimate of the population available to the fishery was made from the number of tags recovered by sampling the commercial catch. It was calculated that approximately 90,000 fish were available to the fishery. About 89,000 fish were calculated to be available to the fishery when the equation N = nt/s was used, where N = the population, n = the sample size, t = the number of fish tagged, and s = the number of tag recoveries. The 95 percent limits of confidence for the population estimate derived from the equation N = nt/s were calculated using the method developed by Chapman (1948). The lower limit was found to be 63,736 fish, and the upper limit was 119,371 fish. Approximately 63,000 of the fish available to the commercial fishery continued the migration to the spawning grounds. Spawning ground tag recoveries provided an estimate of the population in the lower river which was in close agreement with the estimate of the population made from tag recoveries in the commercial fishery. Title: The 1951 Alsea River silver salmon tagging program Author: Oregon. Fish Commission, Cleaver, Fred C. (Frederick Charles), 1916-, Morgan, Alfred R. During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether tagged fish released in different apparent conditions suffered differential mortalities. Under the hypothesis that the recovery of the fish in the commercial fishery was independent of the apparent condition of the fish when it was released, a significant value of chi-square was obtained. However, it was concluded that this significance was a result of sampling differences and not actually due to differences in mortality. The number of fish taken in the commercial catch each week was calculated by dividing the number of pounds in the weekly catch by the average weight of the fish in the samples for that week. It was calculated that the commercial fishery took approximately 14,000 fish during the season, which was only about 15 per cent of the run available to the fishery. This is an extremely low fishing mortality and is considerably lower than had been expected. The number of tags taken each week by the commercial fishery was calculated by dividing the number of fish in the catch each week by the number of fish per tag in the samples for the week. It was calculated that 67 tags were taken during the season by the commercial fishery. This number of recoveries was 15.5 per cent of the 438 tags available to the fishery. With the cooperation of a number of boat moorages on the Alsea River, an estimate of the sport catch of silver salmon was made. It was calculated that the lower river sport fishery took approximately 3,000 adult silvers with an additional 500 fish being taken by the bank fishery. The weight of the total catch of 3,500 fish was calculated to be about 33,000 pounds. This weight formed 20.2 percent of the combined commercial and sport catches. It was calculated that 18 tagged fish were taken in the sport catch. A total of 44 numbered Petersen and jaw tags were recovered from both dead and live fish which had reached spawning areas. This number includes three tags recovered from the spawning grounds of adjacent streams. When the tagged fish were examined according to areas recovered, it was found that Drift Creek had a smaller number of fish per tag than any other area with one exception. Recoveries appeared to be distributed throughout the drainage from any particular time of tagging. Fish enter the lower river together, then separate to the various spawning areas in the system. Several fish moved from the tagging location in the Alsea River to adjacent streams. About 7 percent of the total recoveries in Table 12 were made from streams other than the Alsea River. The Petersen and jaw tag recoveries in the samples of the commercial catch were examined for selection of the Petersen tags by the nets. The percentage by size group in the catch of fish with each type of tag was about the same as the percentage by size group with each type of tag at the time of release. Large losses of tags in the fishery would have been reflected by a higher number of fish per tag on the spawning grounds. Since the gill-nets did not appear to be selective on either type of tag, the Petersen tags, jaw tags, and tag scars were combined in the calculations involving tag recoveries. After the fish moved beyond the fishing area, many still did not move rapidly to the spawning grounds. Several were taken in tidewater or in the vicinity of tidewater 48-58 days after they had been tagged. The average time between tagging and recovery on the spawning grounds was 63 days for live fish and 70 days for dead fish. Using the method proposed by Schaefer (1951a) for obtaining a population estimate from spawning ground recoveries, an estimate of the population available to the fishery was made from the number of tags recovered by sampling the commercial catch. It was calculated that approximately 90,000 fish were available to the fishery. About 89,000 fish were calculated to be available to the fishery when the equation N = nt/s was used, where N = the population, n = the sample size, t = the number of fish tagged, and s = the number of tag recoveries. The 95 percent limits of confidence for the population estimate derived from the equation N = nt/s were calculated using the method developed by Chapman (1948). The lower limit was found to be 63,736 fish, and the upper limit was 119,371 fish. Approximately 63,000 of the fish available to the commercial fishery continued the migration to the spawning grounds. Spawning ground tag recoveries provided an estimate of the population in the lower river which was in close agreement with the estimate of the population made from tag recoveries in the commercial fishery. Close

• 92. [Article] Designing a Monitoring Program to Estimate Estuarine Survival of Anadromous Salmon Smolts: Simulating the Effect of Sample Design on Inference

  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: Designing a Monitoring Program to Estimate Estuarine Survival of Anadromous Salmon Smolts: Simulating the Effect of Sample Design on Inference Author: Schreck, Carl B., Gitelman, Alix I., Romer, Jeremy D., Clements, Shaun 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: Designing a Monitoring Program to Estimate Estuarine Survival of Anadromous Salmon Smolts: Simulating the Effect of Sample Design on Inference Author: Schreck, Carl B., Gitelman, Alix I., Romer, Jeremy D., Clements, Shaun 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

• 93. [Article] Effective size of a wild salmonid population is greatly reduced by hatchery supplementation

  This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. To the ...

  Citation × Citation Citation Abstract Copy Title: Effective size of a wild salmonid population is greatly reduced by hatchery supplementation Author: Blouin, M. S., French, R. A., Marine, M. L., Christie, M. R., Waples, R. S. This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Effective size of a wild salmonid population is greatly reduced by hatchery supplementation Author: Blouin, M. S., French, R. A., Marine, M. L., Christie, M. R., Waples, R. S. This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 94. [Article] Arctic Char Fish Farming in Iceland: Is it a Success?

  Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, ...

  Citation × Citation Citation Abstract Copy Title: Arctic Char Fish Farming in Iceland: Is it a Success? Author: Arnason, Ragnar, Olafsdottir, Gudrun, Heimisson, Asgeir Fridrik Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Title: Arctic Char Fish Farming in Iceland: Is it a Success? Author: Arnason, Ragnar, Olafsdottir, Gudrun, Heimisson, Asgeir Fridrik Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Close

• 95. [Article] The intrusion of logging debris into artificial gravel streambeds

  The objective of this study was to quantitatively describe the intrusion of logging debris into artificial gravel streambeds during conditions of low stream flow with a stable streambed, and begin an analysis ...

  Citation × Citation Citation Abstract Copy Title: The intrusion of logging debris into artificial gravel streambeds Author: Garvin, William Fredrick The objective of this study was to quantitatively describe the intrusion of logging debris into artificial gravel streambeds during conditions of low stream flow with a stable streambed, and begin an analysis of the effect of high flow and unstable streambeds. This study was initiated because prior studies indicated that logging debris was responsible for dissolved oxygen reduction within the gravel bed of spawning streams. Low flow -- stable streambed studies were run for eighteen to twenty days in a flume. Two control samples of the gravel were taken. Logging slash was then placed on the gravel in volumes approximating those of logged streams. A sample was taken every other day for eighteen to twenty days using a device which froze a core of the streambed gravel. Since there were many problems with vandalism and weather, only two low flow replications were completed. shows the large random error which occurs even in the deeper sections. The range of debris concentrations of the two deeper sections for low flow studies one and two were .07 gm/l and .15 gm/l respectively. The average concentration values for low flow studies one and two were .03 gm/l and .02 gm/l respectively. No variables in the high flow study were found to be good predictors of intrusion. Natural random error and the extreme variability of this dynamic system were too great to draw even general conclusions. The range of concentrations of high flow studies one and two were .14 gm/l and .04 gm/l respectively. The average concentration values for high flow studies one and two were .01 gm/l and .02 gm/l respectively. Beneath the armour layer, the streambed exhibits less variability, but the large random error is sufficient to make prediction of intrusion difficult. During high flow periods where the streambed is moving, no predictive equation could be developed to estimate organic material release or incorporation owing to the large variability existing in the system. Title: The intrusion of logging debris into artificial gravel streambeds Author: Garvin, William Fredrick The objective of this study was to quantitatively describe the intrusion of logging debris into artificial gravel streambeds during conditions of low stream flow with a stable streambed, and begin an analysis of the effect of high flow and unstable streambeds. This study was initiated because prior studies indicated that logging debris was responsible for dissolved oxygen reduction within the gravel bed of spawning streams. Low flow -- stable streambed studies were run for eighteen to twenty days in a flume. Two control samples of the gravel were taken. Logging slash was then placed on the gravel in volumes approximating those of logged streams. A sample was taken every other day for eighteen to twenty days using a device which froze a core of the streambed gravel. Since there were many problems with vandalism and weather, only two low flow replications were completed. shows the large random error which occurs even in the deeper sections. The range of debris concentrations of the two deeper sections for low flow studies one and two were .07 gm/l and .15 gm/l respectively. The average concentration values for low flow studies one and two were .03 gm/l and .02 gm/l respectively. No variables in the high flow study were found to be good predictors of intrusion. Natural random error and the extreme variability of this dynamic system were too great to draw even general conclusions. The range of concentrations of high flow studies one and two were .14 gm/l and .04 gm/l respectively. The average concentration values for high flow studies one and two were .01 gm/l and .02 gm/l respectively. Beneath the armour layer, the streambed exhibits less variability, but the large random error is sufficient to make prediction of intrusion difficult. During high flow periods where the streambed is moving, no predictive equation could be developed to estimate organic material release or incorporation owing to the large variability existing in the system. Close

• 96. [Article] In the midst of a revolution : science, fish culture, and the Oregon Game Commission, 1935-1949

  This thesis will address the transformation of biological sciences during the 1930s and 1940s and it effects on fisheries science. It will focus on Oregon State College and specifically the Department ...

  Citation × Citation Citation Abstract Copy Title: In the midst of a revolution : science, fish culture, and the Oregon Game Commission, 1935-1949 Author: Hahn, Linda This thesis will address the transformation of biological sciences during the 1930s and 1940s and it effects on fisheries science. It will focus on Oregon State College and specifically the Department of Fish and Game Management and the interaction with the Oregon Game Commission. Support for mutation theory and neo- Lamarckism lasted throughout this study's time frame. The resulting belief that the environment can directly affect species fitness could have been a factor in fisheries managers' support for fish hatcheries. Throughout this time frame the science of ecology was emerging, but the dominant science of agricultural breeding science within wildlife management took precedence over ecology. Two case studies show changing ideas about agricultural breeding science as applied to wildlife management. In the first case study, the debate concerning fishways over Bonneville Dam shows that fish hatcheries were counted on to mitigate the loss of salmon habitat due to construction, and to act as a failsafe should the fishways fail. When the 1934 Oregon Game Commission members failed to enthusiastically support the construction of the dam and the fishway plans, this thesis argues that the commission members were dismissed in 1935. The second case study addresses the actions of the Oregon Game Commission in placing some high dams on tributaries of the Willamette River, the Willamette Valley project. This thesis shows that the inclusion of ecological principles in the evaluation of fish hatcheries led the commission to oppose this project. For their opposition, this thesis argues that the 1949 Oregon Game Commission members were dismissed. In both cases, this thesis concludes that the federal funding of water development projects played an important role in the dismissals of both Oregon Game Commissions. In addition, the evolving nature of biological science during the 1 930s and 1940s shows that lingering beliefs in mutation theory and neo-Lamarckism would have supported the use of fish hatcheries as a scientifically acceptable solution to declines in fish runs within the scientific tradition of agricultural methods of breeding wildlife. Title: In the midst of a revolution : science, fish culture, and the Oregon Game Commission, 1935-1949 Author: Hahn, Linda This thesis will address the transformation of biological sciences during the 1930s and 1940s and it effects on fisheries science. It will focus on Oregon State College and specifically the Department of Fish and Game Management and the interaction with the Oregon Game Commission. Support for mutation theory and neo- Lamarckism lasted throughout this study's time frame. The resulting belief that the environment can directly affect species fitness could have been a factor in fisheries managers' support for fish hatcheries. Throughout this time frame the science of ecology was emerging, but the dominant science of agricultural breeding science within wildlife management took precedence over ecology. Two case studies show changing ideas about agricultural breeding science as applied to wildlife management. In the first case study, the debate concerning fishways over Bonneville Dam shows that fish hatcheries were counted on to mitigate the loss of salmon habitat due to construction, and to act as a failsafe should the fishways fail. When the 1934 Oregon Game Commission members failed to enthusiastically support the construction of the dam and the fishway plans, this thesis argues that the commission members were dismissed in 1935. The second case study addresses the actions of the Oregon Game Commission in placing some high dams on tributaries of the Willamette River, the Willamette Valley project. This thesis shows that the inclusion of ecological principles in the evaluation of fish hatcheries led the commission to oppose this project. For their opposition, this thesis argues that the 1949 Oregon Game Commission members were dismissed. In both cases, this thesis concludes that the federal funding of water development projects played an important role in the dismissals of both Oregon Game Commissions. In addition, the evolving nature of biological science during the 1 930s and 1940s shows that lingering beliefs in mutation theory and neo-Lamarckism would have supported the use of fish hatcheries as a scientifically acceptable solution to declines in fish runs within the scientific tradition of agricultural methods of breeding wildlife. Close

• 97. [Article] Survival and behavior of juvenile steelhead trout (Oncorhynchus mykiss) in two small estuaries in Oregon

  A number of steelhead (Oncorhynchus mykiss) populations are at risk throughout Oregon, including five populations that are federally listed as threatened or endangered. However, little is known about behavior ...

  Citation × Citation Citation Abstract Copy Title: Survival and behavior of juvenile steelhead trout (Oncorhynchus mykiss) in two small estuaries in Oregon Author: Romer, Jeremy D. A number of steelhead (Oncorhynchus mykiss) populations are at risk throughout Oregon, including five populations that are federally listed as threatened or endangered. However, little is known about behavior and survival of these fish as they transition from freshwater to seawater. We investigated whether estuarine survival varies on a temporal scale within or between years, on a spatial scale between zones within the estuary, and between basins within the same distinct population segment. We implanted acoustic transmitters on 69 wild steelhead smolts in the Nehalem basin and 70 in the Alsea basin and compared run timing, migration rate, and estuarine residence times between basins. We also measured gill ATP-ase levels and parasite loads in each basin to evaluate the relationship between these indices and migration timing, life history strategy or age of smoltification. In general, only 40-50% of the wild steelhead smolts tagged at upstream smolt traps were detected entering the ocean, although survival was highly variable among years. The majority of "mortality" occurred in the lower estuary near the mouth. Wild steelhead smolts spent a median of 0.72 and 0.83 d in the estuary in the Nehalem and Alsea basin, respectively, in 2009. This research provides a baseline by which we can monitor temporal changes in the survival and behavior of juvenile salmon in the estuary. Such information is vital for monitoring the impact of estuarine restoration and reiterates the importance of the lower river and estuary environment for smolt survival. Title: Survival and behavior of juvenile steelhead trout (Oncorhynchus mykiss) in two small estuaries in Oregon Author: Romer, Jeremy D. A number of steelhead (Oncorhynchus mykiss) populations are at risk throughout Oregon, including five populations that are federally listed as threatened or endangered. However, little is known about behavior and survival of these fish as they transition from freshwater to seawater. We investigated whether estuarine survival varies on a temporal scale within or between years, on a spatial scale between zones within the estuary, and between basins within the same distinct population segment. We implanted acoustic transmitters on 69 wild steelhead smolts in the Nehalem basin and 70 in the Alsea basin and compared run timing, migration rate, and estuarine residence times between basins. We also measured gill ATP-ase levels and parasite loads in each basin to evaluate the relationship between these indices and migration timing, life history strategy or age of smoltification. In general, only 40-50% of the wild steelhead smolts tagged at upstream smolt traps were detected entering the ocean, although survival was highly variable among years. The majority of "mortality" occurred in the lower estuary near the mouth. Wild steelhead smolts spent a median of 0.72 and 0.83 d in the estuary in the Nehalem and Alsea basin, respectively, in 2009. This research provides a baseline by which we can monitor temporal changes in the survival and behavior of juvenile salmon in the estuary. Such information is vital for monitoring the impact of estuarine restoration and reiterates the importance of the lower river and estuary environment for smolt survival. Close

• 98. [Article] Modeling the impact of logging debris on the dissolved oxygen balance of small mountain streams

  Previous research has indicated that considerable amounts of finely divided slash accumulate in small mountain streams following timber harvesting. The subsequent biological decomposition of this organic ...

  Citation × Citation Citation Abstract Copy Title: Modeling the impact of logging debris on the dissolved oxygen balance of small mountain streams Author: Berry, John David Previous research has indicated that considerable amounts of finely divided slash accumulate in small mountain streams following timber harvesting. The subsequent biological decomposition of this organic matter can result i.n the reduction of dissolved oxygen (DO) concentration to levels as low as 0.6 ppm. These DO levels are lethal to the salmon and trout fry which inhabit these waters during the summer months. The purpose of this study was to verify the results of previous research on the biochemical oxygen demand (BOD) characteristics of Douglas-fir needles, western hemlock needles, and red alder leaves, and to develop an oxygen balance model to describe the effect of logging debris BOD on the dissolved oxygen of small mountain streams. The concept of the leaching process was examined and refined. As a result K₄, the leaching rate constant, was introduced to describe the addition of leachate to the stream. This necessitated redefining K₁, the first order decay rate constant, as it had been reported in previous studies. Slash may be described by its ultimate oxygen demand, or potential BOD, and two rate constants, K₁ and K₄. Manometric BOD tests were run for 20-day periods to estimate the potential BOD and the rate constants K₁ and K₄. The 20-day ultimate BOD, K₁ and K₄ estimates at 20°C were: 139mg 0₂ /gm (dry weight), 0.266 and 0.189 per day for Douglas-fir needles, 183mg 0₂/gm (dry weight), 0.202 and 0.089 per day for western hemlock needles, and 226 mg 0₂/gm (dry weight), 0.121 and 0.141 per day for red alder leaves. Laboratory experiments designed to examine the possibilities of occurrence and impact of nitrification on the oxygen demand curve concluded that even though it is possible to observe nitrification under special conditions, coastal streams are generally too nitrogen and carbon poor for nitrification to exert a significant oxygen demand. Even with the addition of large amounts of vegetation to the stream water, an available form of nitrogen must be added to produce detectable amounts of nitrogenous oxygen demand. It was found that the presence of nitrification cannot be detected in small mountain streams by nitrate analysis because of rapid fixation of nitrogen. Thus, the nitrification process appears to be of more concern for evaluating nutrient pathways and fixation than oxygen demand. The leachate of the Douglas-firs western hemlock, and red alder vegetation was analyzed for sugar and phenol concentration and rate of leaching. The vegetation was gas sterilized using ethylene oxide. The sterile vegetation was placed in autoclaved aliquots of water and sealed. The leachate of each vegetation type was analyzed at periodic intervals over 90 days, and the leachate expressed in glucose and gallic acid equivalents. Of the 120 samples treated, only one showed signs of contamination. The sugar and phenolic release rate constants for Douglas-fir and western hemlock were very similar; 0.049 and 0.062 for Douglas-fir sugars and phenols respectively and 0.060 and 0.046 for western hemlock sugars and phenols. All of these rates are less than the leaching rates derived by BOD experimentation. These differences may be due to biological interaction in the leaching process. The leaching rate constants for red alder leaves were much higher than the experimental rates, 0.88 and 0.187 for sugars and phenols respectively. The mean maximum sugar concentration was: 117 mg glucose equivalent / gm (dry weight) for Douglas-fir needles, 86 mg glucose equivalents / gm (dry weight) for western hemlock needles, 121 mg glucose equivalents / gm (dry weight) for red alder leaves, and 50 mg glucose equivalent/gm (dry weight) for dissected Douglas-fir twigs. No rate constant was computed for Douglas-fir twigs because of the lack of fit to an exponential function. Experimentation of the effects of temperature showed & significant response of potential BOD, K₁ and K₄ to variations in water temperature from 15 to 27°C. In general, ultimate BOD, K₁ and K₄ values increased with increasing water temperature. The effect of mass concentration on ultimate BOD, K₁ and K₄ were negligible for vegetative loadings of 4 to 16 gm, fresh weight per liter. The second phase of this study involved constructing a finite difference model of the dissolved oxygen balance in small mountain streams. A fixed cell approach was used to demonstrate the negligible effects of dispersion on pollutant and oxygen concentration. This then allowed the use of the much more efficient Lagrange variation of the finite difference modeling technique, utilizing a moving cell. By using available data and estimates of the distribution of slash in a simulated stream following clearcutting along 991 ft of the stream, DO levels as low as 5.72 ppm were computed for the simulated stream 5890 ft below the top of the clearcut. At these DO concentrations, salmon and trout fry experience "critical" stress conditions. Further model runs indicated that by reducing the length of the clearcut or by removing a portion of slash this condition could be avoided. Title: Modeling the impact of logging debris on the dissolved oxygen balance of small mountain streams Author: Berry, John David Previous research has indicated that considerable amounts of finely divided slash accumulate in small mountain streams following timber harvesting. The subsequent biological decomposition of this organic matter can result i.n the reduction of dissolved oxygen (DO) concentration to levels as low as 0.6 ppm. These DO levels are lethal to the salmon and trout fry which inhabit these waters during the summer months. The purpose of this study was to verify the results of previous research on the biochemical oxygen demand (BOD) characteristics of Douglas-fir needles, western hemlock needles, and red alder leaves, and to develop an oxygen balance model to describe the effect of logging debris BOD on the dissolved oxygen of small mountain streams. The concept of the leaching process was examined and refined. As a result K₄, the leaching rate constant, was introduced to describe the addition of leachate to the stream. This necessitated redefining K₁, the first order decay rate constant, as it had been reported in previous studies. Slash may be described by its ultimate oxygen demand, or potential BOD, and two rate constants, K₁ and K₄. Manometric BOD tests were run for 20-day periods to estimate the potential BOD and the rate constants K₁ and K₄. The 20-day ultimate BOD, K₁ and K₄ estimates at 20°C were: 139mg 0₂ /gm (dry weight), 0.266 and 0.189 per day for Douglas-fir needles, 183mg 0₂/gm (dry weight), 0.202 and 0.089 per day for western hemlock needles, and 226 mg 0₂/gm (dry weight), 0.121 and 0.141 per day for red alder leaves. Laboratory experiments designed to examine the possibilities of occurrence and impact of nitrification on the oxygen demand curve concluded that even though it is possible to observe nitrification under special conditions, coastal streams are generally too nitrogen and carbon poor for nitrification to exert a significant oxygen demand. Even with the addition of large amounts of vegetation to the stream water, an available form of nitrogen must be added to produce detectable amounts of nitrogenous oxygen demand. It was found that the presence of nitrification cannot be detected in small mountain streams by nitrate analysis because of rapid fixation of nitrogen. Thus, the nitrification process appears to be of more concern for evaluating nutrient pathways and fixation than oxygen demand. The leachate of the Douglas-firs western hemlock, and red alder vegetation was analyzed for sugar and phenol concentration and rate of leaching. The vegetation was gas sterilized using ethylene oxide. The sterile vegetation was placed in autoclaved aliquots of water and sealed. The leachate of each vegetation type was analyzed at periodic intervals over 90 days, and the leachate expressed in glucose and gallic acid equivalents. Of the 120 samples treated, only one showed signs of contamination. The sugar and phenolic release rate constants for Douglas-fir and western hemlock were very similar; 0.049 and 0.062 for Douglas-fir sugars and phenols respectively and 0.060 and 0.046 for western hemlock sugars and phenols. All of these rates are less than the leaching rates derived by BOD experimentation. These differences may be due to biological interaction in the leaching process. The leaching rate constants for red alder leaves were much higher than the experimental rates, 0.88 and 0.187 for sugars and phenols respectively. The mean maximum sugar concentration was: 117 mg glucose equivalent / gm (dry weight) for Douglas-fir needles, 86 mg glucose equivalents / gm (dry weight) for western hemlock needles, 121 mg glucose equivalents / gm (dry weight) for red alder leaves, and 50 mg glucose equivalent/gm (dry weight) for dissected Douglas-fir twigs. No rate constant was computed for Douglas-fir twigs because of the lack of fit to an exponential function. Experimentation of the effects of temperature showed & significant response of potential BOD, K₁ and K₄ to variations in water temperature from 15 to 27°C. In general, ultimate BOD, K₁ and K₄ values increased with increasing water temperature. The effect of mass concentration on ultimate BOD, K₁ and K₄ were negligible for vegetative loadings of 4 to 16 gm, fresh weight per liter. The second phase of this study involved constructing a finite difference model of the dissolved oxygen balance in small mountain streams. A fixed cell approach was used to demonstrate the negligible effects of dispersion on pollutant and oxygen concentration. This then allowed the use of the much more efficient Lagrange variation of the finite difference modeling technique, utilizing a moving cell. By using available data and estimates of the distribution of slash in a simulated stream following clearcutting along 991 ft of the stream, DO levels as low as 5.72 ppm were computed for the simulated stream 5890 ft below the top of the clearcut. At these DO concentrations, salmon and trout fry experience "critical" stress conditions. Further model runs indicated that by reducing the length of the clearcut or by removing a portion of slash this condition could be avoided. Close

• 99. [Article] The value of short run in-stream temperature forecasts : an application to salmonids in the Klamath and John Day Rivers

  Water temperature is an important measure of water quality, as well as a dominant factor affecting aquatic life within the stream environment. Elevated water temperatures can decrease the survival rate ...

  Citation × Citation Citation Abstract Copy Title: The value of short run in-stream temperature forecasts : an application to salmonids in the Klamath and John Day Rivers Author: Huang, Biao Water temperature is an important measure of water quality, as well as a dominant factor affecting aquatic life within the stream environment. Elevated water temperatures can decrease the survival rate of fish in each life stage. Cold water species, such as salmonids, are particularly susceptible to elevated water temperatures. For example, increased water temperatures are believed to have been the major cause of the large fish kill observed in the Klamath River in September 2002. This thesis examines the economic value of short-term water temperature forecasts for salmonid management. Forecasts may have value if they allow the water resource manager to make more cost-effective water allocation decisions. Specifically, this study considers two applications. One is the case of adult Chinook salmon (O. tshawytscha) returning to the Lower Klamath River in California, where cold water could be released upstream from the Lewiston Dam into the Trinity River to lower The Klamath River water temperature. Water releases create opportunity costs because of foregone hydropower production and crop irrigation. The second application is to juvenile summer steelhead (Oncorhynchus mykiss) in the North Fork John Day River, where water could be purchased from agricultural uses to prevent excessive water temperature increases. This generates opportunity costs in the form of lower crop yields. This thesis incorporates bio-physical models and water temperature distribution data into a Bayesian framework to simulate the potential fish populations after ten generations and the corresponding opportunity cost of water under different forecast accuracies. Simulation results indicate that the marginal cost in the Klamath River decreases from about $80 per fish saved when the forecast standard deviation is 6 to about $40 when the forecast standard deviation is 0(perfect forecast). In the John Day River the marginal cost per fish decreases from $34 for a standard deviation of 6 to $29 for a standard deviation of 0. A key result of the thesis is the pattern of decreasing marginal costs as the forecast accuracy increases, suggesting that provision and use of such stream temperature forecasts would have value to society. Title: The value of short run in-stream temperature forecasts : an application to salmonids in the Klamath and John Day Rivers Author: Huang, Biao Water temperature is an important measure of water quality, as well as a dominant factor affecting aquatic life within the stream environment. Elevated water temperatures can decrease the survival rate of fish in each life stage. Cold water species, such as salmonids, are particularly susceptible to elevated water temperatures. For example, increased water temperatures are believed to have been the major cause of the large fish kill observed in the Klamath River in September 2002. This thesis examines the economic value of short-term water temperature forecasts for salmonid management. Forecasts may have value if they allow the water resource manager to make more cost-effective water allocation decisions. Specifically, this study considers two applications. One is the case of adult Chinook salmon (O. tshawytscha) returning to the Lower Klamath River in California, where cold water could be released upstream from the Lewiston Dam into the Trinity River to lower The Klamath River water temperature. Water releases create opportunity costs because of foregone hydropower production and crop irrigation. The second application is to juvenile summer steelhead (Oncorhynchus mykiss) in the North Fork John Day River, where water could be purchased from agricultural uses to prevent excessive water temperature increases. This generates opportunity costs in the form of lower crop yields. This thesis incorporates bio-physical models and water temperature distribution data into a Bayesian framework to simulate the potential fish populations after ten generations and the corresponding opportunity cost of water under different forecast accuracies. Simulation results indicate that the marginal cost in the Klamath River decreases from about $80 per fish saved when the forecast standard deviation is 6 to about $40 when the forecast standard deviation is 0(perfect forecast). In the John Day River the marginal cost per fish decreases from $34 for a standard deviation of 6 to $29 for a standard deviation of 0. A key result of the thesis is the pattern of decreasing marginal costs as the forecast accuracy increases, suggesting that provision and use of such stream temperature forecasts would have value to society. Close

• 100. [Article] The relationships between fluctuations in oceanographic conditions, forage fishes, predatory fishes, predator food habits, and juvenile salmonid marine survival off the Columbia River

  Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other ...

  Citation × Citation Citation Abstract Copy Title: The relationships between fluctuations in oceanographic conditions, forage fishes, predatory fishes, predator food habits, and juvenile salmonid marine survival off the Columbia River Author: Emmett, Robert L. Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other fishes. Changes in the biological and physical environment off the Columbia River region affects the distribution and abundance of predatory fishes and their feeding, forage fishes, and juvenile salmonid marine survival. From 1998-2004, forage fish and predatory fish distribution and abundance off the Columbia River was quantified by surface trawling at night during spring/summer. The effect of predation on salmonids was measured by stomach analysis of predatory fishes. During the study period (1998-2004), forage fishes increased in abundance by orders of magnitude and were strongly related to the abundance of cold-water copepods the previous year. Higher forage fish populations were also linked to cooler ocean conditions and perhaps fewer predatory Pacific hake (Merluccius productus). Most forage fishes were distributed nearshore while predators had a more offshore distribution. Pacific hake was most abundant in 1998, 2003, and 2004; warm ocean years. Jack mackerel (Trachurus symmetricus) was most abundant during 1999-2002; relatively cool ocean years. Deep (50-m) ocean temperatures and the date of the spring transition, when nearshore currents switched from northward to southward, were good predictors of Pacific hake abundance in the study area. Forage fish or salmonid occurrence in a haul was negatively related to the occurrence of predators. Pacific hake and jack mackerel ate primarily euphausiids and small fishes. Salmonids were rarely eaten by either predator. However, because the Pacific hake population can be very large, hake predation can be a significant source of juvenile salmon mortality off the Columbia River during some years. A trophic model showed that marine mortality of Columbia River juvenile salmonids may be related to the abundance of Pacific hake and forage fishes. A multiple regression using the predictions from the trophic model of annual numbers of juvenile salmonids eaten by hake and Columbia River spring flows as independent variables, accounted for much of the variation observed in the annual marine survival of Columbia River coho (Oncorhynchus kisutch) and Chinook salmon (O. tshawytscha), the dependent variable. Future research should identify the physical and biological forces that alter the feeding habits, migration and movements of Pacific hake and jack mackerel off the Northwest, and how Columbia River flows affect trophic interactions. Title: The relationships between fluctuations in oceanographic conditions, forage fishes, predatory fishes, predator food habits, and juvenile salmonid marine survival off the Columbia River Author: Emmett, Robert L. Salmonid run sizes are strongly affected by their early marine stage. Fully understanding the life history of salmonids means understanding how they interact with their marine environment and with other fishes. Changes in the biological and physical environment off the Columbia River region affects the distribution and abundance of predatory fishes and their feeding, forage fishes, and juvenile salmonid marine survival. From 1998-2004, forage fish and predatory fish distribution and abundance off the Columbia River was quantified by surface trawling at night during spring/summer. The effect of predation on salmonids was measured by stomach analysis of predatory fishes. During the study period (1998-2004), forage fishes increased in abundance by orders of magnitude and were strongly related to the abundance of cold-water copepods the previous year. Higher forage fish populations were also linked to cooler ocean conditions and perhaps fewer predatory Pacific hake (Merluccius productus). Most forage fishes were distributed nearshore while predators had a more offshore distribution. Pacific hake was most abundant in 1998, 2003, and 2004; warm ocean years. Jack mackerel (Trachurus symmetricus) was most abundant during 1999-2002; relatively cool ocean years. Deep (50-m) ocean temperatures and the date of the spring transition, when nearshore currents switched from northward to southward, were good predictors of Pacific hake abundance in the study area. Forage fish or salmonid occurrence in a haul was negatively related to the occurrence of predators. Pacific hake and jack mackerel ate primarily euphausiids and small fishes. Salmonids were rarely eaten by either predator. However, because the Pacific hake population can be very large, hake predation can be a significant source of juvenile salmon mortality off the Columbia River during some years. A trophic model showed that marine mortality of Columbia River juvenile salmonids may be related to the abundance of Pacific hake and forage fishes. A multiple regression using the predictions from the trophic model of annual numbers of juvenile salmonids eaten by hake and Columbia River spring flows as independent variables, accounted for much of the variation observed in the annual marine survival of Columbia River coho (Oncorhynchus kisutch) and Chinook salmon (O. tshawytscha), the dependent variable. Future research should identify the physical and biological forces that alter the feeding habits, migration and movements of Pacific hake and jack mackerel off the Northwest, and how Columbia River flows affect trophic interactions. Close