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• 1. [Article] An exploratory study of the social factors of small dam removal : Chiloquin Dam at Sprague River Mile 0.87, Oregon

  Several reports related to dams and dam removal have been released this decade by non-governmental organizations including Dam Removal: Science and Decision Making by The Heinz Center which focused on ...

  Citation × Citation Citation Abstract Copy Title: An exploratory study of the social factors of small dam removal : Chiloquin Dam at Sprague River Mile 0.87, Oregon Author: Hatch, Jason M. Several reports related to dams and dam removal have been released this decade by non-governmental organizations including Dam Removal: Science and Decision Making by The Heinz Center which focused on small dams, since most of the dams removed to date as well as those likely to be removed in the near future fall into this category. The report found that there is a need for case study social research on small dam removal. Accordingly, this thesis seeks to identify the social and policy factors that influenced the decision to remove Chiloquin Dam on the Sprague River, Oregon. This irrigation diversion dam was constructed from 1914-1918 for the Klamath Tribes under the federal Indian Irrigation Service program and subsequently transferred to the Modoc Point Irrigation District in 1973, after termination of the Tribes by the federal Government. Chiloquin Dam was identified in a 1988 Endangered Species Act listing as a primary factor in Lost River and shortnose sucker species decline, a species of cultural significance for the Klamath Tribes. Although early reports, including those by Klamath Project irrigators, called for improved fish passage at Chiloquin Dam, it was not until jeopardy biological opinions triggered a shut off of water to the federal irrigation project in 2001, that Chiloquin Dam became a priority. Directed by legislation, the United States Bureau of Reclamation convened stakeholders in the Chiloquin Dam Fish Passage Study for nine months in 2002-2003 to determine a preferred alternative for fish passage, of which dam removal was recommended. To identify the social and policy factors that influenced the Chiloquin Dam removal decision, 21 informants were interviewed including participants in the Fish Passage Study as well as those involved in the 1988 Endangered Species Act (ESA) listing. Among the findings, respondents perceived that the ESA was the driving policy force, along with tribal restoration (the tribal trust responsibility) in the dam removal decision. Modoc Point Irrigation District members (Off-project) and tribal respondents believe that the dam removal was motivated by political support for Klamath Project irrigators. Despite these beliefs and divergent expectations for Chiloquin Dam fish passage, with the political imperative and resources, an agreement was reached in which each party had their needs addressed. An analysis using the social construction model found that the events of 2001 threatened to push irrigation interests from a powerful advantaged political position. The Fish Passage Study presented capacity and inducement instruments that responded to irrigation and tribal concerns and may also serve to restore the irrigation position as an advantaged social construction. Overall, uncertain science, differing beliefs of what dam removal would mean, and a lack of political priority served to delay action on fish passage at Chiloquin Dam from the ESA listing in 1988. Title: An exploratory study of the social factors of small dam removal : Chiloquin Dam at Sprague River Mile 0.87, Oregon Author: Hatch, Jason M. Several reports related to dams and dam removal have been released this decade by non-governmental organizations including Dam Removal: Science and Decision Making by The Heinz Center which focused on small dams, since most of the dams removed to date as well as those likely to be removed in the near future fall into this category. The report found that there is a need for case study social research on small dam removal. Accordingly, this thesis seeks to identify the social and policy factors that influenced the decision to remove Chiloquin Dam on the Sprague River, Oregon. This irrigation diversion dam was constructed from 1914-1918 for the Klamath Tribes under the federal Indian Irrigation Service program and subsequently transferred to the Modoc Point Irrigation District in 1973, after termination of the Tribes by the federal Government. Chiloquin Dam was identified in a 1988 Endangered Species Act listing as a primary factor in Lost River and shortnose sucker species decline, a species of cultural significance for the Klamath Tribes. Although early reports, including those by Klamath Project irrigators, called for improved fish passage at Chiloquin Dam, it was not until jeopardy biological opinions triggered a shut off of water to the federal irrigation project in 2001, that Chiloquin Dam became a priority. Directed by legislation, the United States Bureau of Reclamation convened stakeholders in the Chiloquin Dam Fish Passage Study for nine months in 2002-2003 to determine a preferred alternative for fish passage, of which dam removal was recommended. To identify the social and policy factors that influenced the Chiloquin Dam removal decision, 21 informants were interviewed including participants in the Fish Passage Study as well as those involved in the 1988 Endangered Species Act (ESA) listing. Among the findings, respondents perceived that the ESA was the driving policy force, along with tribal restoration (the tribal trust responsibility) in the dam removal decision. Modoc Point Irrigation District members (Off-project) and tribal respondents believe that the dam removal was motivated by political support for Klamath Project irrigators. Despite these beliefs and divergent expectations for Chiloquin Dam fish passage, with the political imperative and resources, an agreement was reached in which each party had their needs addressed. An analysis using the social construction model found that the events of 2001 threatened to push irrigation interests from a powerful advantaged political position. The Fish Passage Study presented capacity and inducement instruments that responded to irrigation and tribal concerns and may also serve to restore the irrigation position as an advantaged social construction. Overall, uncertain science, differing beliefs of what dam removal would mean, and a lack of political priority served to delay action on fish passage at Chiloquin Dam from the ESA listing in 1988. Close

• 2. [Article] A topography of dams in China : impacts to agriculture, labor, and migration

  Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, ...

  Citation × Citation Citation Abstract Copy Title: A topography of dams in China : impacts to agriculture, labor, and migration Author: Foster-Moore, Eric Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, remains contentious due to the potential for negative environmental and socioeconomic impacts. Despite numerous case studies, there is little systematic empirical evidence about either the contribution of dams to human development or their negative impacts to humans and the environment. Identifying the impact of dams also presents a methodological challenge because dam placement is likely endogenous to socioeconomic outcomes. The topographic suitability of a landscape for dam construction provides a source of exogenous variation in dam siting, which, building on the work of previous scholars, I exploit to identify the effect of large dams on agriculture, population change, and labor allocation. My results suggest that dams have decreased grain production in the counties where they were built and have drawn labor into non-agricultural fields. Dams appear to impact population subgroups in predictable ways and create identifiable winners and losers. Title: A topography of dams in China : impacts to agriculture, labor, and migration Author: Foster-Moore, Eric Dams are often promoted as a tool to reduce poverty and spur economic development. Dam construction worldwide, and particularly in China, which has built nearly half the world's large dams since 1949, remains contentious due to the potential for negative environmental and socioeconomic impacts. Despite numerous case studies, there is little systematic empirical evidence about either the contribution of dams to human development or their negative impacts to humans and the environment. Identifying the impact of dams also presents a methodological challenge because dam placement is likely endogenous to socioeconomic outcomes. The topographic suitability of a landscape for dam construction provides a source of exogenous variation in dam siting, which, building on the work of previous scholars, I exploit to identify the effect of large dams on agriculture, population change, and labor allocation. My results suggest that dams have decreased grain production in the counties where they were built and have drawn labor into non-agricultural fields. Dams appear to impact population subgroups in predictable ways and create identifiable winners and losers. Close

• 3. [Article] Relationship of inbreeding to heterosis in swine

  Records of 889 litters of three populations of swine farrowed between 1962 and 1973 were analyzed by least squares procedures. Estimates were obtained for the effects of age and inbreeding of dam, inbreeding ...

  Citation × Citation Citation Abstract Copy Title: Relationship of inbreeding to heterosis in swine Author: Liu, Lillian Ling-Ling Records of 889 litters of three populations of swine farrowed between 1962 and 1973 were analyzed by least squares procedures. Estimates were obtained for the effects of age and inbreeding of dam, inbreeding of litter, inbreeding of dam's dam and inbreeding of the sire of the litter on litter size traits and weight at birth and at weaning. Heterosis was calculated for maternal performance of crossbred dams and for crossbred litters from purebred dams. Positive significant effects of age of dam were found on total number born at birth in all three populations, on average pig birth weight in Yorkshires and in Composites, and on number of pigs born alive in Composites. Inbreeding of dam showed negative significant effects on litter size at birth in Yorkshires and in all of the litter traits except average pig birth weight in Composites. The only positive significant effect of inbreeding of dam was on average pig birth weight in Berkshires. Inbreeding of litter had no significant effect in Composites, negative significant effects on number of pigs at weaning, percent survival and average birth weight in Yorkshires, and on all the litter traits except total number born and average pig birth weight in Berkshires. Inbreeding of dam's dam had no significant effect on any litter trait except a highly positive one on number of pigs weaned in Yorkshires. Inbreeding of sire of litter showed a highly positive significant effect on average pig birth weight in Berkshires, a negative significant effect on litter size in Yorkshires and on average weaning weight in Composites. Crossbred dams showed more heterosis than crossbred litters from purebred dams for litter performance traits. The comparison between purebred and crossbred litters from purebred dams with various degrees of inbreeding were studied. Heterosis was greatest for number born alive and weaned; it tended to increase as purebred dams became more inbred. Adjustment for inbreeding decreased heterosis to levels comparable to that in non-inbred dams. Title: Relationship of inbreeding to heterosis in swine Author: Liu, Lillian Ling-Ling Records of 889 litters of three populations of swine farrowed between 1962 and 1973 were analyzed by least squares procedures. Estimates were obtained for the effects of age and inbreeding of dam, inbreeding of litter, inbreeding of dam's dam and inbreeding of the sire of the litter on litter size traits and weight at birth and at weaning. Heterosis was calculated for maternal performance of crossbred dams and for crossbred litters from purebred dams. Positive significant effects of age of dam were found on total number born at birth in all three populations, on average pig birth weight in Yorkshires and in Composites, and on number of pigs born alive in Composites. Inbreeding of dam showed negative significant effects on litter size at birth in Yorkshires and in all of the litter traits except average pig birth weight in Composites. The only positive significant effect of inbreeding of dam was on average pig birth weight in Berkshires. Inbreeding of litter had no significant effect in Composites, negative significant effects on number of pigs at weaning, percent survival and average birth weight in Yorkshires, and on all the litter traits except total number born and average pig birth weight in Berkshires. Inbreeding of dam's dam had no significant effect on any litter trait except a highly positive one on number of pigs weaned in Yorkshires. Inbreeding of sire of litter showed a highly positive significant effect on average pig birth weight in Berkshires, a negative significant effect on litter size in Yorkshires and on average weaning weight in Composites. Crossbred dams showed more heterosis than crossbred litters from purebred dams for litter performance traits. The comparison between purebred and crossbred litters from purebred dams with various degrees of inbreeding were studied. Heterosis was greatest for number born alive and weaned; it tended to increase as purebred dams became more inbred. Adjustment for inbreeding decreased heterosis to levels comparable to that in non-inbred dams. Close

• 4. [Article] Evaluating downstream channel changes in response to a small dam removal on the Calapooia River, Oregon with respect to measurement errors and prior aerial photo observed changes

  The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. ...

  Citation × Citation Citation Abstract Copy Title: Evaluating downstream channel changes in response to a small dam removal on the Calapooia River, Oregon with respect to measurement errors and prior aerial photo observed changes Author: Walter, Cara The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. The Brownsville Dam, a 2.1 m tall concrete dam on the Calapooia River, Oregon, was removed in 2007. We surveyed cross sections below the dam during the summers prior to (2007) and follow (2008) removal, and we analyzed aerial photos from 1994 to 2006. The field surveys and aerial photos were used to map the low flow channel and bars over 1.3 km downstream from the dam and in an upstream control reach. Three types of measurement error (position error, identification error, and wetted boundary datum error) were assessed for the field surveys and aerial photos in order make the two methods of measurement more comparable. The first year after the dam removal, we observed changes in bar width, wetted width, and wetted width midpoint as large as 17 m ± 3 m immediately below the dam. We inferred that channel changes below the dam after removal were a result of the removal through comparison with pre-dam removal aerial photos, where changes up to 67 m ± 24 m were predominantly far from the dam, and an upstream control, where changes were only as large as 9 m ± 5 m. We conclude with suggestions of best practices for reducing errors, including establishment of permanent monuments for field surveys, taking measurements at similar, well-known discharges, and generating the highest-quality digital aerial photos through source and scanning choices. Title: Evaluating downstream channel changes in response to a small dam removal on the Calapooia River, Oregon with respect to measurement errors and prior aerial photo observed changes Author: Walter, Cara The objective of this study was to evaluate the use of aerial photos as a substitute for multiple-year pre-removal field data to assess the downstream channel changes associated with a small dam removal. The Brownsville Dam, a 2.1 m tall concrete dam on the Calapooia River, Oregon, was removed in 2007. We surveyed cross sections below the dam during the summers prior to (2007) and follow (2008) removal, and we analyzed aerial photos from 1994 to 2006. The field surveys and aerial photos were used to map the low flow channel and bars over 1.3 km downstream from the dam and in an upstream control reach. Three types of measurement error (position error, identification error, and wetted boundary datum error) were assessed for the field surveys and aerial photos in order make the two methods of measurement more comparable. The first year after the dam removal, we observed changes in bar width, wetted width, and wetted width midpoint as large as 17 m ± 3 m immediately below the dam. We inferred that channel changes below the dam after removal were a result of the removal through comparison with pre-dam removal aerial photos, where changes up to 67 m ± 24 m were predominantly far from the dam, and an upstream control, where changes were only as large as 9 m ± 5 m. We conclude with suggestions of best practices for reducing errors, including establishment of permanent monuments for field surveys, taking measurements at similar, well-known discharges, and generating the highest-quality digital aerial photos through source and scanning choices. Close

• 5. [Article] The Life Cycle of Dams: An Analysis of Policy Change on the Rogue River, Oregon

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: The Life Cycle of Dams: An Analysis of Policy Change on the Rogue River, Oregon Author: McDermott, Wendy D. Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: The Life Cycle of Dams: An Analysis of Policy Change on the Rogue River, Oregon Author: McDermott, Wendy D. Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 6. [Article] Model-prototype correlation of cofferdam closure with tetrahedrons

  Citation × Citation Citation Abstract Copy Title: Model-prototype correlation of cofferdam closure with tetrahedrons Author: Weiss, Edwin Victor Title: Model-prototype correlation of cofferdam closure with tetrahedrons Author: Weiss, Edwin Victor Close

• 7. [Article] Design and construction of earth dams

  Citation × Citation Citation Abstract Copy Title: Design and construction of earth dams Author: Haq, Shafiqul Title: Design and construction of earth dams Author: Haq, Shafiqul Close

• 8. [Article] The design of gravity masonry dams

  Citation × Citation Citation Abstract Copy Title: The design of gravity masonry dams Author: Su, Lansing Title: The design of gravity masonry dams Author: Su, Lansing Close

• 9. [Article] Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA

  The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region ...

  Citation × Citation Citation Abstract Copy Title: Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA Author: Lampman, Ralph Tatsuo The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region in the past 40 to 50 years. Among the many potential causes of this decline, obstruction of migration routes has likely played a substantial role. Within the North Umpqua River basin in southwest Oregon, USA, I focused on the following three research goals: 1) to describe the passage efficiency and migration routes of adult Pacific lamprey at Winchester Dam; 2) to evaluate the seasonal movement patterns of adult Pacific lamprey and their use of holding habitat at Winchester Dam in relation to temperature conditions; and 3) to portray the diversity of upstream migratory behaviors of adult Pacific lamprey and the environmental factors that influence these behaviors. This radio telemetry study was conducted between March 2009 and August 2011 with a combination of fixed stations and manual tracking. Passage efficiency was low in both years (8% and 19%, respectively), and all tagged lamprey that successfully passed the dam used routes other than the fish ladder. Lamprey that migrated early within the run and those with relatively small tags had higher passage rates and traveled further than the other groups of lamprey. Lamprey released above of the dam or those that passed the dam on their own distributed themselves widely in the upstream environment, suggesting that the dam deterred their upstream migration. Using mark-recapture data for the two years, the adult Pacific lamprey population upstream of Winchester Dam was estimated at 960 (95% C.I. [188, 4760]) in 2009 and 556 (95% C.I. [110, 2798]) in 2010, which was considerably lower than historical counts at the dam (between 14,532-46,785 in 1965-1971). Most tagged lamprey that did not pass the dam remained at the base of the dam at the end of the summer migration (63% in 2009 and 67% in 2010). Types of habitat most frequently used by lamprey downstream from the dam included the dam surface (wooden structures with crevices), interface zones between fast and slow water, and highway bridge pilings. The lamprey movement changed considerably between August and September, and the frequency of movements decreased sharply during this period. Tagged lamprey were detected using thermal refuges immediately downstream of the dam that were 0.4 to 2.8 C° colder than the mean river temperature at the dam, and this temperature differential increased as the season progressed. Lamprey may be seeking overwintering habitat associated with hyporheic exchange flows at the dam towards the end of the summer season after their display of heightened activity early in the summer. Ninety-five percent of the overall upstream migration took place during the first spring/summer period, and only small-scale upstream movements were observed during the winter and second spring/summer (4% and 1%, respectively). The rate of upstream migration (median) was the fastest during the initial migration phase and was 1.9 km/day (ranging from 0.3 to 11.0 km/day) for tagged lamprey released above Winchester Dam. During winter, 71% of the lamprey remained in the same location where they initiated holding. Multiple regression analysis indicated that the total upstream distance traveled by individual lamprey was most strongly related to presence/absence of Winchester Dam, relative tag size, and water temperature and photoperiod conditions at release. The presence of Winchester Dam, large relative tag size, and high water temperature / short photoperiod conditions at release significantly reduced upstream migration distance. Title: Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA Author: Lampman, Ralph Tatsuo The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region in the past 40 to 50 years. Among the many potential causes of this decline, obstruction of migration routes has likely played a substantial role. Within the North Umpqua River basin in southwest Oregon, USA, I focused on the following three research goals: 1) to describe the passage efficiency and migration routes of adult Pacific lamprey at Winchester Dam; 2) to evaluate the seasonal movement patterns of adult Pacific lamprey and their use of holding habitat at Winchester Dam in relation to temperature conditions; and 3) to portray the diversity of upstream migratory behaviors of adult Pacific lamprey and the environmental factors that influence these behaviors. This radio telemetry study was conducted between March 2009 and August 2011 with a combination of fixed stations and manual tracking. Passage efficiency was low in both years (8% and 19%, respectively), and all tagged lamprey that successfully passed the dam used routes other than the fish ladder. Lamprey that migrated early within the run and those with relatively small tags had higher passage rates and traveled further than the other groups of lamprey. Lamprey released above of the dam or those that passed the dam on their own distributed themselves widely in the upstream environment, suggesting that the dam deterred their upstream migration. Using mark-recapture data for the two years, the adult Pacific lamprey population upstream of Winchester Dam was estimated at 960 (95% C.I. [188, 4760]) in 2009 and 556 (95% C.I. [110, 2798]) in 2010, which was considerably lower than historical counts at the dam (between 14,532-46,785 in 1965-1971). Most tagged lamprey that did not pass the dam remained at the base of the dam at the end of the summer migration (63% in 2009 and 67% in 2010). Types of habitat most frequently used by lamprey downstream from the dam included the dam surface (wooden structures with crevices), interface zones between fast and slow water, and highway bridge pilings. The lamprey movement changed considerably between August and September, and the frequency of movements decreased sharply during this period. Tagged lamprey were detected using thermal refuges immediately downstream of the dam that were 0.4 to 2.8 C° colder than the mean river temperature at the dam, and this temperature differential increased as the season progressed. Lamprey may be seeking overwintering habitat associated with hyporheic exchange flows at the dam towards the end of the summer season after their display of heightened activity early in the summer. Ninety-five percent of the overall upstream migration took place during the first spring/summer period, and only small-scale upstream movements were observed during the winter and second spring/summer (4% and 1%, respectively). The rate of upstream migration (median) was the fastest during the initial migration phase and was 1.9 km/day (ranging from 0.3 to 11.0 km/day) for tagged lamprey released above Winchester Dam. During winter, 71% of the lamprey remained in the same location where they initiated holding. Multiple regression analysis indicated that the total upstream distance traveled by individual lamprey was most strongly related to presence/absence of Winchester Dam, relative tag size, and water temperature and photoperiod conditions at release. The presence of Winchester Dam, large relative tag size, and high water temperature / short photoperiod conditions at release significantly reduced upstream migration distance. Close

• 10. [Article] Review : bird predation of juvenile salmonids and management of birds near 14 Columbia Basin dams

  Bird predation of juvenile salmonids and/or bird predation control are reviewed for 14 of the 18 mainstem dams on the Columbia and Snake Rivers, but there was little information for some of these dams. California ...

  Citation × Citation Citation Abstract Copy Title: Review : bird predation of juvenile salmonids and management of birds near 14 Columbia Basin dams Author: Bayer, Range D., 1947- Bird predation of juvenile salmonids and/or bird predation control are reviewed for 14 of the 18 mainstem dams on the Columbia and Snake Rivers, but there was little information for some of these dams. California gulls, ring-billed gulls, Caspian terns, double-crested cormorants, American white pelicans, and several other bird species have been reported as predators of juvenile salmon and steelhead at these dams. Most estimates of the amount of this predation have been 2% or less of salmonids passing a dam. This is less than the percentage of juvenile salmonids killed during dam passage, and it has not been determined what proportion of salmonids taken by birds were already dead or mortally injured from dam passage. Thus, it is not clear what portion of bird predation is of viable salmonids that would have otherwise survived. Further, it appears that most juvenile salmonids in the Columbia Basin are not federally listed as threatened or endangered, so it is not known what impact bird predation at dams may have on listed salmonids. Nevertheless, predation may significantly affect certain salmon stocks, so it cannot be dismissed as unimportant. Bird management includes installing wires above the water at dam tailraces. Closely spaced wires are effective in keeping out flying birds. However, not all areas where birds feed on fish below dams can be covered with wires, the wires have sometimes been placed too far apart to keep out flying birds, and nonflying birds can go under wires. Consequently, Wildlife Services (which was known as Animal Damage Control prior to 1998) of the U.S. Department of Agriculture has also nonlethally harassed and lethally taken birds at dams after it has been requested to do so. Studies by staff of the U.S. Army Corps of Engineers have shown that nonlethal and lethal control by Washington Wildlife Services at The Dalles and John Day Dams needed to be repeated because birds would return. During 1997-1998, Wildlife Services dispersed at least 20,682 birds (mostly gulls) and lethally took at least 3,143 birds at these two dams. Most juvenile salmonids migrate past dams from April through early June, although many subyearling chinook migrate during July and August. Thus, bird control to protect juvenile salmonids would be most effective during April-July and perhaps through August for subyearling chinook. Beginning in August, many juvenile American shad are also migrating over lower Columbia dams and then can be more abundant than migrating salmonids; however, few shad pass Snake River dams and at least one mid-Columbia dam. Washington Wildlife Services' bird control has been during April-September at mid-Columbia dams and apparently during spring through winter at lower Columbia dams, so its control may sometimes occur when few juvenile salmonids are migrating. Although bird management at some dams has occurred since at least 1992, it has not yet been determined if this control is cost effective (i.e., the costs of bird control are less than the costs of predation). Washington Wildlife Services asserts that the cost of bird predation can be estimated by the cost of controlling predation. With this circular logic, Wildlife Services could spend a considerable amount of taxpayer or electric ratepayer money controlling predators that may be taking an insignificant number of viable juvenile salmonids and justify doing so because it has spent so much money. Consequently, it is important for there to be realistic evidence for the need or benefits of predator control, so that control is cost effective. Washington Wildlife Services has not been forthcoming in answering general questions about its activities at Columbia Basin dams and asserts that a federal Texas court case precludes disclosure of information. However, it seems that Wildlife Services may be using that court case to avoid scrutiny because the court ruled that Wildlife Services not provide information that could identify cooperators with Wildlife Services, not that it withhold all information about its activities. Further, Wildlife Services appears to have violated this court decision by providing other agencies with reports of its predator control activities that identifies specific cooperators, so Washington Wildlife Services seems to have selectively chosen when to use the court ruling as an excuse to not give out general information. Fish-eating bird control has proceeded very differently in the Columbia Estuary than at Columbia Basin dams. In the Estuary, bird predation was quantified in 1997 to establish a need for bird control; agency, tribal, and public consultations about a management plan were conducted, management actions began to be implemented in 1999, and predation reduction began to be quantified in 2000. At dams, Washington Wildlife Services assumed bird predation to be significant, initiated bird management before the amount of predation was measured, appears to have done less consultation with the public, other agencies, or tribes about its management actions; and assumed that its predator control actions have significantly reduced predation. Title: Review : bird predation of juvenile salmonids and management of birds near 14 Columbia Basin dams Author: Bayer, Range D., 1947- Bird predation of juvenile salmonids and/or bird predation control are reviewed for 14 of the 18 mainstem dams on the Columbia and Snake Rivers, but there was little information for some of these dams. California gulls, ring-billed gulls, Caspian terns, double-crested cormorants, American white pelicans, and several other bird species have been reported as predators of juvenile salmon and steelhead at these dams. Most estimates of the amount of this predation have been 2% or less of salmonids passing a dam. This is less than the percentage of juvenile salmonids killed during dam passage, and it has not been determined what proportion of salmonids taken by birds were already dead or mortally injured from dam passage. Thus, it is not clear what portion of bird predation is of viable salmonids that would have otherwise survived. Further, it appears that most juvenile salmonids in the Columbia Basin are not federally listed as threatened or endangered, so it is not known what impact bird predation at dams may have on listed salmonids. Nevertheless, predation may significantly affect certain salmon stocks, so it cannot be dismissed as unimportant. Bird management includes installing wires above the water at dam tailraces. Closely spaced wires are effective in keeping out flying birds. However, not all areas where birds feed on fish below dams can be covered with wires, the wires have sometimes been placed too far apart to keep out flying birds, and nonflying birds can go under wires. Consequently, Wildlife Services (which was known as Animal Damage Control prior to 1998) of the U.S. Department of Agriculture has also nonlethally harassed and lethally taken birds at dams after it has been requested to do so. Studies by staff of the U.S. Army Corps of Engineers have shown that nonlethal and lethal control by Washington Wildlife Services at The Dalles and John Day Dams needed to be repeated because birds would return. During 1997-1998, Wildlife Services dispersed at least 20,682 birds (mostly gulls) and lethally took at least 3,143 birds at these two dams. Most juvenile salmonids migrate past dams from April through early June, although many subyearling chinook migrate during July and August. Thus, bird control to protect juvenile salmonids would be most effective during April-July and perhaps through August for subyearling chinook. Beginning in August, many juvenile American shad are also migrating over lower Columbia dams and then can be more abundant than migrating salmonids; however, few shad pass Snake River dams and at least one mid-Columbia dam. Washington Wildlife Services' bird control has been during April-September at mid-Columbia dams and apparently during spring through winter at lower Columbia dams, so its control may sometimes occur when few juvenile salmonids are migrating. Although bird management at some dams has occurred since at least 1992, it has not yet been determined if this control is cost effective (i.e., the costs of bird control are less than the costs of predation). Washington Wildlife Services asserts that the cost of bird predation can be estimated by the cost of controlling predation. With this circular logic, Wildlife Services could spend a considerable amount of taxpayer or electric ratepayer money controlling predators that may be taking an insignificant number of viable juvenile salmonids and justify doing so because it has spent so much money. Consequently, it is important for there to be realistic evidence for the need or benefits of predator control, so that control is cost effective. Washington Wildlife Services has not been forthcoming in answering general questions about its activities at Columbia Basin dams and asserts that a federal Texas court case precludes disclosure of information. However, it seems that Wildlife Services may be using that court case to avoid scrutiny because the court ruled that Wildlife Services not provide information that could identify cooperators with Wildlife Services, not that it withhold all information about its activities. Further, Wildlife Services appears to have violated this court decision by providing other agencies with reports of its predator control activities that identifies specific cooperators, so Washington Wildlife Services seems to have selectively chosen when to use the court ruling as an excuse to not give out general information. Fish-eating bird control has proceeded very differently in the Columbia Estuary than at Columbia Basin dams. In the Estuary, bird predation was quantified in 1997 to establish a need for bird control; agency, tribal, and public consultations about a management plan were conducted, management actions began to be implemented in 1999, and predation reduction began to be quantified in 2000. At dams, Washington Wildlife Services assumed bird predation to be significant, initiated bird management before the amount of predation was measured, appears to have done less consultation with the public, other agencies, or tribes about its management actions; and assumed that its predator control actions have significantly reduced predation. Close