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• 31. [Image] Federal Register - Endangered and Threatened Wildlife and Plants; Notice of Revised 90-Day Petition Finding and Initiation of a 5-Year Status Review of the Lost River Sucker and Shortnose Sucker

  	We, the U.S. Fish and Wildlife Service (Service), announce a revised 90-day finding for a petition to remove the Lost River sucker [Deltistes luxatus) and shortnose sucker [Chasmistes brevirostris) throughout ...
  	Citation × Citation Citation Abstract Copy Title: Federal Register - Endangered and Threatened Wildlife and Plants; Notice of Revised 90-Day Petition Finding and Initiation of a 5-Year Status Review of the Lost River Sucker and Shortnose Sucker Author: Larsen, Ron Year: 2004, 2008, 2005 We, the U.S. Fish and Wildlife Service (Service), announce a revised 90-day finding for a petition to remove the Lost River sucker [Deltistes luxatus) and shortnose sucker [Chasmistes brevirostris) throughout their ranges from the Federal List of Threatened and Endangered Wildlife and Plants (List), pursuant to the Endangered Species Act (Act) (16 U.S.C. 1531 et seq.). We find that the petition does not present substantial scientific or commercial information indicating that delisting of the Lost River and shortnose suckers may be warranted. As a result of the 1995, 1996, and 1997 fish die-offs, the endangered suckers experienced significant losses of thousands of adult suckers and have not recovered. Although the petition and information in our files do not provide new information relevant to the status of the Lost River and shortnose suckers, we are initiating a 5-year review of these species under section 4(c)(2)(A) of the Act to consider any new information that has become available as a result of recent actions to reduce threats to the species, and to provide the States, tribes, agencies, university researchers, and the public an opportunity to provide information on the status of the species. We are requesting any new information on the Lost River and shortnose suckers since their original listing as endangered species in 1988 (53 FR 27130) Title: Federal Register - Endangered and Threatened Wildlife and Plants; Notice of Revised 90-Day Petition Finding and Initiation of a 5-Year Status Review of the Lost River Sucker and Shortnose Sucker Author: Larsen, Ron Year: 2004, 2008, 2005 We, the U.S. Fish and Wildlife Service (Service), announce a revised 90-day finding for a petition to remove the Lost River sucker [Deltistes luxatus) and shortnose sucker [Chasmistes brevirostris) throughout their ranges from the Federal List of Threatened and Endangered Wildlife and Plants (List), pursuant to the Endangered Species Act (Act) (16 U.S.C. 1531 et seq.). We find that the petition does not present substantial scientific or commercial information indicating that delisting of the Lost River and shortnose suckers may be warranted. As a result of the 1995, 1996, and 1997 fish die-offs, the endangered suckers experienced significant losses of thousands of adult suckers and have not recovered. Although the petition and information in our files do not provide new information relevant to the status of the Lost River and shortnose suckers, we are initiating a 5-year review of these species under section 4(c)(2)(A) of the Act to consider any new information that has become available as a result of recent actions to reduce threats to the species, and to provide the States, tribes, agencies, university researchers, and the public an opportunity to provide information on the status of the species. We are requesting any new information on the Lost River and shortnose suckers since their original listing as endangered species in 1988 (53 FR 27130) Close

• 32. [Image] Genetic analysis of Klamath River green sturgeon (acipensar [i.e. acipenser] medirostris)

  	Abstract The utility of using isozyme analysis to study the stock structure among West Coast populations of green sturgeon (Acipenser medirostris) was assessed. Isozyme analysis was not determined ...
  	Citation × Citation Citation Abstract Copy Title: Genetic analysis of Klamath River green sturgeon (acipensar [i.e. acipenser] medirostris) Author: Mulligan, Helen Year: 2000, 2005 Abstract The utility of using isozyme analysis to study the stock structure among West Coast populations of green sturgeon (Acipenser medirostris) was assessed. Isozyme analysis was not determined to be an adequate method for assessing stock structure in green sturgeon for the following reasons: 1) the complex nature of isozyme expression 2) the relatively poor resolution of enzyme systems for our samples 3) the invasive nature of collecting tissue samples for isozyme analysis, which necessitates sacrificing the fish, precludes collection of samples from some rivers. The stomach contents of 23 green sturgeon collected from fish harvested in the Klamath River were analyzed. Only four stomachs contained identifiable food items, with the others containing food far too digested for identification, gravel, or no contents. Two stomachs contained the small gastropod, Olivellapyna, one stomach contained the carapace remains of a female Dungeness crab, Cancer magister, and one stomach contained the posterior portions of three ammocoetes, Lampetra tridentata. Preliminary analysis was conducted using mtDNA to assess the potential of using this technique for assessing the stock structure of green sturgeon. Although the Klamath River Fishery Restoration Program did not fund this analysis, the results are presented because this work was designed to yield complementary information to the isozyme study. No diagnostic differences were detected between samples collected from the Klamath River and the Columbia River estuary using Restriction Fragment Length Polymorphism analysis. Study results indicated that microsateliite DNA analyst might be the most appropriate current genetic technique for assessing the population structure of green sturgeon. Title: Genetic analysis of Klamath River green sturgeon (acipensar [i.e. acipenser] medirostris) Author: Mulligan, Helen Year: 2000, 2005 Abstract The utility of using isozyme analysis to study the stock structure among West Coast populations of green sturgeon (Acipenser medirostris) was assessed. Isozyme analysis was not determined to be an adequate method for assessing stock structure in green sturgeon for the following reasons: 1) the complex nature of isozyme expression 2) the relatively poor resolution of enzyme systems for our samples 3) the invasive nature of collecting tissue samples for isozyme analysis, which necessitates sacrificing the fish, precludes collection of samples from some rivers. The stomach contents of 23 green sturgeon collected from fish harvested in the Klamath River were analyzed. Only four stomachs contained identifiable food items, with the others containing food far too digested for identification, gravel, or no contents. Two stomachs contained the small gastropod, Olivellapyna, one stomach contained the carapace remains of a female Dungeness crab, Cancer magister, and one stomach contained the posterior portions of three ammocoetes, Lampetra tridentata. Preliminary analysis was conducted using mtDNA to assess the potential of using this technique for assessing the stock structure of green sturgeon. Although the Klamath River Fishery Restoration Program did not fund this analysis, the results are presented because this work was designed to yield complementary information to the isozyme study. No diagnostic differences were detected between samples collected from the Klamath River and the Columbia River estuary using Restriction Fragment Length Polymorphism analysis. Study results indicated that microsateliite DNA analyst might be the most appropriate current genetic technique for assessing the population structure of green sturgeon. Close

• 33. [Image] Draft upper Williamson River Watershed assessment

  	"Prepared for Klamath Basin Ecosystem Foundation, and the Upper Williamson River Catchment Group, in cooperation with the Upper Klamath Basin Working Group, and the Klamath Watershed Council."
  	Citation × Citation Citation Abstract Copy Title: Draft upper Williamson River Watershed assessment Author: David Evans and Associates, Inc. Year: 2004, 2005 "Prepared for Klamath Basin Ecosystem Foundation, and the Upper Williamson River Catchment Group, in cooperation with the Upper Klamath Basin Working Group, and the Klamath Watershed Council." Title: Draft upper Williamson River Watershed assessment Author: David Evans and Associates, Inc. Year: 2004, 2005 "Prepared for Klamath Basin Ecosystem Foundation, and the Upper Williamson River Catchment Group, in cooperation with the Upper Klamath Basin Working Group, and the Klamath Watershed Council." Close

• 34. [Image] The Oregon conservation strategy

  	v, 419 p.; col.ill.; col.maps; "February 2006"; Foreword by Marla Rae, Chair, Oregon Fish and Wildlife Commission
  	Citation × Citation Citation Abstract Copy Title: The Oregon conservation strategy Year: 2006 v, 419 p.; col.ill.; col.maps; "February 2006"; Foreword by Marla Rae, Chair, Oregon Fish and Wildlife Commission Title: The Oregon conservation strategy Year: 2006 v, 419 p.; col.ill.; col.maps; "February 2006"; Foreword by Marla Rae, Chair, Oregon Fish and Wildlife Commission Close

• 35. [Image] Williamson River delta restoration project : environmental assessment

  	"May 2000"; From cover: Prepared for U.S. Department of Agriculture/Natural Resources Conservation Service, 2316 South 6th Street, Suite C, Klamath Falls, Oregon 97601. In Partnership with The Nature Conservancy, ...
  	Citation × Citation Citation Abstract Copy Title: Williamson River delta restoration project : environmental assessment Year: 2000, 2005 "May 2000"; From cover: Prepared for U.S. Department of Agriculture/Natural Resources Conservation Service, 2316 South 6th Street, Suite C, Klamath Falls, Oregon 97601. In Partnership with The Nature Conservancy, 821 SE 14th Avenue, Portland, Oregon 97214 and US Fish and Wildlife Service, US Bureau of Reclamation, Klamath Tribes, PacifiCorp, Cell Tech International; Includes bibliographic references (p. 60-66) Title: Williamson River delta restoration project : environmental assessment Year: 2000, 2005 "May 2000"; From cover: Prepared for U.S. Department of Agriculture/Natural Resources Conservation Service, 2316 South 6th Street, Suite C, Klamath Falls, Oregon 97601. In Partnership with The Nature Conservancy, 821 SE 14th Avenue, Portland, Oregon 97214 and US Fish and Wildlife Service, US Bureau of Reclamation, Klamath Tribes, PacifiCorp, Cell Tech International; Includes bibliographic references (p. 60-66) Close

• 36. [Image] Water Symposium: Symposium before the Committee on Energy and Natural Resources, United States Senate, One Hundred Ninth Congress, First Session, on Water Issues, April 5, 2005

  	iii; 99p.; "Printed for the use of the Committee on Energy and Natural Resources"; Distributed to some depository libraries in microfiche
  	Citation × Citation Citation Abstract Copy Title: Water Symposium: Symposium before the Committee on Energy and Natural Resources, United States Senate, One Hundred Ninth Congress, First Session, on Water Issues, April 5, 2005 Author: Water Symposium (2005: Washington, D.C.) Year: 2005, 2006 iii; 99p.; "Printed for the use of the Committee on Energy and Natural Resources"; Distributed to some depository libraries in microfiche Title: Water Symposium: Symposium before the Committee on Energy and Natural Resources, United States Senate, One Hundred Ninth Congress, First Session, on Water Issues, April 5, 2005 Author: Water Symposium (2005: Washington, D.C.) Year: 2005, 2006 iii; 99p.; "Printed for the use of the Committee on Energy and Natural Resources"; Distributed to some depository libraries in microfiche Close

• 37. [Image] Oregon lampreys : natural history, status, and analysis of management issues

  	Executive Summary The jawless lampreys are remnants of the oldest vertebrates in the world. Oregon has somewhere between eight and a dozen species of these primitive fishes. Their taxonomy is obscure ...
  	Citation × Citation Citation Abstract Copy Title: Oregon lampreys : natural history, status, and analysis of management issues Author: Kostow, Kathryn Year: 2002, 2008, 2005 Executive Summary The jawless lampreys are remnants of the oldest vertebrates in the world. Oregon has somewhere between eight and a dozen species of these primitive fishes. Their taxonomy is obscure because different species tend to look very similar through most of their life cycle, and they have not been well-studied in Oregon. Lampreys occur in the Columbia Basin, including the lower Snake River, along the Oregon coast, in the upper Klamath Basin, and in Goose Lake Basin in southeastern Oregon. They all begin life in fresh water where juveniles burrow into silt and filter feed on algae. As some species approach adulthood they migrate to the ocean or to lakes where they briefly become ecto-parasites, feeding on other live fishes by attaching to them with sucker disc mouths. Other species remain non-parasitic. In addition to some enigmatic species identities, we generally have very little information about the detailed distributions, life histories and basic biology of lampreys. Lampreys became a conservation concern in the early 1990s when tribal co-managers and some Oregon Department of Fish and Wildlife (ODFW) staff noted that populations of Pacific Lampreys, Lampetra tridentata, were apparently declining to perilously low numbers. Pacific Lampreys were listed as an Oregon State sensitive species in 1993 and were given further legal protected status by the state in 1997 (OAR 635-044-0130). Lamprey status is difficult to assess for several reasons: 1) Most observations of lampreys in fresh water are of juveniles and it is difficult to tell the various species apart, even to the extent that the various species are currently clearly designated; 2) Data on lamprey is only collected incidental to monitoring of salmonids. The design and efficiency of the data collection effort is not always adequate for lampreys; and 3) We have very few historic data sets for lampreys. Therefore we often cannot determine how the abundances and distributions we see now compare with those in the past. The limited data that we have suggests that lampreys have declined through many parts of their ranges. The most precipitous declines appear to be in the upper Columbia and Snake basins where we have some historic data from mainstem dam counts. Pacific Lampreys have declined to only about 200 adults annually passing the Snake River dams. We also have evidence of declines of Pacific Lampreys in the lower Columbia and on the Oregon coast, although our data is quite limited. We have little to no information about any of the other species of lampreys. We are not even sure whether some of the recognized species, like the River Lamprey (L. ayresi), is still present in Oregon. This paper concludes with a Problem Analysis for Oregon lampreys. Our biggest problem is poor information, ranging from not knowing basic species identity to having inefficient or no systematic monitoring of lamprey abundance and distribution. ODFW continued an annual harvest on Pacific Lamprey in the Willamette Basin in 2001, but we lack the necessary information to assess the affects of the harvest on the population. Major habitat problems that affect lampreys include upstream passage over artificial barriers, a need for lamprey-friendly screening of water diversions, and urban and agricultural development of low-gradient flood plain habitats. Title: Oregon lampreys : natural history, status, and analysis of management issues Author: Kostow, Kathryn Year: 2002, 2008, 2005 Executive Summary The jawless lampreys are remnants of the oldest vertebrates in the world. Oregon has somewhere between eight and a dozen species of these primitive fishes. Their taxonomy is obscure because different species tend to look very similar through most of their life cycle, and they have not been well-studied in Oregon. Lampreys occur in the Columbia Basin, including the lower Snake River, along the Oregon coast, in the upper Klamath Basin, and in Goose Lake Basin in southeastern Oregon. They all begin life in fresh water where juveniles burrow into silt and filter feed on algae. As some species approach adulthood they migrate to the ocean or to lakes where they briefly become ecto-parasites, feeding on other live fishes by attaching to them with sucker disc mouths. Other species remain non-parasitic. In addition to some enigmatic species identities, we generally have very little information about the detailed distributions, life histories and basic biology of lampreys. Lampreys became a conservation concern in the early 1990s when tribal co-managers and some Oregon Department of Fish and Wildlife (ODFW) staff noted that populations of Pacific Lampreys, Lampetra tridentata, were apparently declining to perilously low numbers. Pacific Lampreys were listed as an Oregon State sensitive species in 1993 and were given further legal protected status by the state in 1997 (OAR 635-044-0130). Lamprey status is difficult to assess for several reasons: 1) Most observations of lampreys in fresh water are of juveniles and it is difficult to tell the various species apart, even to the extent that the various species are currently clearly designated; 2) Data on lamprey is only collected incidental to monitoring of salmonids. The design and efficiency of the data collection effort is not always adequate for lampreys; and 3) We have very few historic data sets for lampreys. Therefore we often cannot determine how the abundances and distributions we see now compare with those in the past. The limited data that we have suggests that lampreys have declined through many parts of their ranges. The most precipitous declines appear to be in the upper Columbia and Snake basins where we have some historic data from mainstem dam counts. Pacific Lampreys have declined to only about 200 adults annually passing the Snake River dams. We also have evidence of declines of Pacific Lampreys in the lower Columbia and on the Oregon coast, although our data is quite limited. We have little to no information about any of the other species of lampreys. We are not even sure whether some of the recognized species, like the River Lamprey (L. ayresi), is still present in Oregon. This paper concludes with a Problem Analysis for Oregon lampreys. Our biggest problem is poor information, ranging from not knowing basic species identity to having inefficient or no systematic monitoring of lamprey abundance and distribution. ODFW continued an annual harvest on Pacific Lamprey in the Willamette Basin in 2001, but we lack the necessary information to assess the affects of the harvest on the population. Major habitat problems that affect lampreys include upstream passage over artificial barriers, a need for lamprey-friendly screening of water diversions, and urban and agricultural development of low-gradient flood plain habitats. Close

• 38. [Image] Klamath River Basin issues and activities

  	Klamath River Basin Issues and Activities: An Overview Summary The Klamath River Basin, an area on the California-Oregon border, has become a focal point for local and national discussions on water ...
  	Citation × Citation Citation Abstract Copy Title: Klamath River Basin issues and activities Author: Kyna Powers Year: 2005, 2008, 2006 Klamath River Basin Issues and Activities: An Overview Summary The Klamath River Basin, an area on the California-Oregon border, has become a focal point for local and national discussions on water management and water scarcity. Water and species management issues were brought to the forefront when severe drought in 2001 exacerbated competition for scarce water resources and generated conflict among several interests - farmers, Indian tribes, commercial and sport fishermen, other recreationists, federal wildlife refuge managers, environmental groups, and state, local, and tribal governments. The conflicts over water distribution and allocation are physically and legally complex, reflecting the varied and sometimes competing uses of limited water supplies in the Basin. For management purposes, the Basin is divided at Iron Gate Dam into the Upper and Lower Basins. As is true in many regions in the West, the federal government plays a prominent role in the Klamath Basin's water management. This role stems from three primary activities: (1) the operation and management of the Bureau of Reclamation's Klamath Water Project and Central Valley Project (e.g., Trinity River dams); (2) management of federal lands in the Basin, including five national wildlife refuges, several national forests, and public lands; and (3) implementation of federal laws, such as the Endangered Species Act (ESA), Clean Water Act (CWA), and National Environmental Policy Act (NEPA). Conflict was sparked in April of 2001 when the Bureau of Reclamation, which has supplied water to farms in the Upper Basin for nearly 100 years, announced that "no water [would] be available" for farms normally receiving water from the Upper Klamath Lake to avoid jeopardizing the existence of three fish species listed as endangered or threatened under the ESA. While some water was subsequently made available to some farmers from other sources (e.g., wells and other Bureau sources), many farmers faced serious hardships. During Reclamation's operations in September of 2002, warm water temperatures and atypically low flows in the lower Klamath contributed to the death of at least 33,000 adult salmonids. This die-off damaged fish stocks and the tribes, commercial fishermen, and recreational anglers that catch Klamath fish. There have been many studies, Biological Opinions, and operating plans over recent years, all of which have been controversial. The events of 2001 and 2002 prompted renewed efforts to resolve water conflicts in the Klamath Basin. Congress has responded to the controversy in a number of ways, including holding oversight hearings and appropriating funds for activities in the area. This report provides an overview of recent conflict in the Klamath Basin, with an emphasis on activities in the Upper Basin, and summarizes some of the activities taking place to improve water supply reliability and fish survival. This report will be updated as events warrant. Title: Klamath River Basin issues and activities Author: Kyna Powers Year: 2005, 2008, 2006 Klamath River Basin Issues and Activities: An Overview Summary The Klamath River Basin, an area on the California-Oregon border, has become a focal point for local and national discussions on water management and water scarcity. Water and species management issues were brought to the forefront when severe drought in 2001 exacerbated competition for scarce water resources and generated conflict among several interests - farmers, Indian tribes, commercial and sport fishermen, other recreationists, federal wildlife refuge managers, environmental groups, and state, local, and tribal governments. The conflicts over water distribution and allocation are physically and legally complex, reflecting the varied and sometimes competing uses of limited water supplies in the Basin. For management purposes, the Basin is divided at Iron Gate Dam into the Upper and Lower Basins. As is true in many regions in the West, the federal government plays a prominent role in the Klamath Basin's water management. This role stems from three primary activities: (1) the operation and management of the Bureau of Reclamation's Klamath Water Project and Central Valley Project (e.g., Trinity River dams); (2) management of federal lands in the Basin, including five national wildlife refuges, several national forests, and public lands; and (3) implementation of federal laws, such as the Endangered Species Act (ESA), Clean Water Act (CWA), and National Environmental Policy Act (NEPA). Conflict was sparked in April of 2001 when the Bureau of Reclamation, which has supplied water to farms in the Upper Basin for nearly 100 years, announced that "no water [would] be available" for farms normally receiving water from the Upper Klamath Lake to avoid jeopardizing the existence of three fish species listed as endangered or threatened under the ESA. While some water was subsequently made available to some farmers from other sources (e.g., wells and other Bureau sources), many farmers faced serious hardships. During Reclamation's operations in September of 2002, warm water temperatures and atypically low flows in the lower Klamath contributed to the death of at least 33,000 adult salmonids. This die-off damaged fish stocks and the tribes, commercial fishermen, and recreational anglers that catch Klamath fish. There have been many studies, Biological Opinions, and operating plans over recent years, all of which have been controversial. The events of 2001 and 2002 prompted renewed efforts to resolve water conflicts in the Klamath Basin. Congress has responded to the controversy in a number of ways, including holding oversight hearings and appropriating funds for activities in the area. This report provides an overview of recent conflict in the Klamath Basin, with an emphasis on activities in the Upper Basin, and summarizes some of the activities taking place to improve water supply reliability and fish survival. This report will be updated as events warrant. Close

• 39. [Image] Relation between selected water-quality variables and lake level in Upper Klamath and Agency Lakes, Oregon

  	Relation Between Selected Water-Quality Constituents and Lake Stage in Upper Klamath and Agency Lakes, Oregon By Tamara M. Wood, Gregory J. Fuhrer, and Jennifer L. Morace SUMMARY Upper Klamath Lake is ...
  	Citation × Citation Citation Abstract Copy Title: Relation between selected water-quality variables and lake level in Upper Klamath and Agency Lakes, Oregon Author: Wood, Tamara M. Year: 1996, 2005, 2004 Relation Between Selected Water-Quality Constituents and Lake Stage in Upper Klamath and Agency Lakes, Oregon By Tamara M. Wood, Gregory J. Fuhrer, and Jennifer L. Morace SUMMARY Upper Klamath Lake is a large (140 square-mile), shallow (mean depth about 8 ft) lake in south-central Oregon that the historical record indicates has been eutrophic since its discovery by non-Native Americans. In recent decades, however, the lake has had annual occurrences of near-monoculture blooms of the blue-green alga Aphanizomenon flos-aquae. In 1988 two sucker species endemic to the lake, the Lost River sucker (Deltistes luxatus) and the shortnose sucker (Chasmistes brevirostris), were listed as endangered by the U.S. Fish and Wildlife Service, and it has been proposed that the poor water quality conditions associated with extremely long and productive blooms are contributing to the decline of those species. It has also been proposed that the low lake levels made possible by the construction of a dam at the outlet from the lake in 1921 have contributed to worsening water quality through a variety of possible mechanisms (Jacob Kann, Klamath Tribes, written com-mun., 1995). One such mechanism would be an increase in internal phosphorus loading from resuspended sediments (Jacoby and others, 1982), resulting from an increase in bottom shear stresses at lower lake levels (Laenen and LeTourneau, 1996), leading in turn to more intense algal blooms. Another possible mechanism is an earlier triggering of algal blooms. When early spring lake levels are low, greater light intensity at the sediment surface might speed recruitment of algal cells from the sediments. Sediment recruitment has been shown to be an important contributor to water column biomass increases in A. flos aquae (Barbiero and Kann, 1994) and Gloeotrichia echinulata (Barbiero, 1993). An earlier bloom could result in poor water quality conditions occurring earlier in the year, when young-of-the-year fish may be more susceptible to those conditions. Lake level can also influence water quality directly. An increased frequency of sediment resuspension at lower lake levels could increase chemical and biological oxygen demand, resulting in decreased dissolved oxygen concentrations. Sediment oxygen demand also may be enhanced at lower lake levels because it is concentrated over a smaller volume of water. Some compensation for increased oxygen demand at lower lake levels might be provided by increased reaeration, if the water column mixes from top to bottom more frequently. Based on the analysis of data that they have been collecting for several years, the Klamath Tribes recently recommended that the Bureau of Reclamation (Reclamation) modify the operating plan for the dam to make the minimum lake levels for the June-August period more closely resemble pre-dam conditions (Jacob Kann, written commun., 1995). The U.S. Geological Survey (USGS) was asked to analyze the available data for the lake and to assess whether the evidence exists to conclude that year-to-year differences in certain lake water-quality variables are related to year-to-year differences in lake level. The results of the analysis will be used as scientific input in the process of developing an operating plan for the Link River Dam. Datasets Two water-quality datasets were analyzed. The first was a series of hourly records of pH, dissolved oxygen, and water temperature, each of approximately a week's duration. The records were collected at 3 sites over 3 years, 1992 through 1994, with enough consistency to define the seasonal patterns. This dataset provided information about the diel extremes in dissolved oxygen and pH and the seasonal pattern in the diel cycle, but measurements were limited to a depth of 1 m(3.28 ft). The second dataset was a set of depth profiles of pH and dissolved oxygen and concurrent depth-integrated samples for nutrients and chlo-rophyll-a. The profiles were collected at approximately biweekly intervals at nine sites (seven in Upper Klamath and two in Agency Lake) over the 5 years 1990 through 1994. These depth profiles provided information on the depth-dependence of dissolved oxygen and pH, and allowed more extensive year-to-year comparisons than did the hourly records. Because measurements were made at each site only once during the sampling day, however, they did not capture the daily extremes in water quality. Lake level is measured daily by the USGS at three sites around the lake: Rocky Point, Rattlesnake Point, and near the city of Klamath Falls. These daily measurements are then used to compute a spatially weighted average of the lake level that is reported in the USGS annual Water-Data Report for Oregon. The average lake levels were used in this report. Two climatic datasets were used in this report; both were collected at the Klamath Falls airport. Air temperature was recorded as a daily maximum and daily minimum value. Cloud cover was quantized on a daily basis into one of seven levels. Because the focus of this study was primarily to examine possible relations between water quality and lake level, the lake level data provide an important context for the discussions that follow. Title: Relation between selected water-quality variables and lake level in Upper Klamath and Agency Lakes, Oregon Author: Wood, Tamara M. Year: 1996, 2005, 2004 Relation Between Selected Water-Quality Constituents and Lake Stage in Upper Klamath and Agency Lakes, Oregon By Tamara M. Wood, Gregory J. Fuhrer, and Jennifer L. Morace SUMMARY Upper Klamath Lake is a large (140 square-mile), shallow (mean depth about 8 ft) lake in south-central Oregon that the historical record indicates has been eutrophic since its discovery by non-Native Americans. In recent decades, however, the lake has had annual occurrences of near-monoculture blooms of the blue-green alga Aphanizomenon flos-aquae. In 1988 two sucker species endemic to the lake, the Lost River sucker (Deltistes luxatus) and the shortnose sucker (Chasmistes brevirostris), were listed as endangered by the U.S. Fish and Wildlife Service, and it has been proposed that the poor water quality conditions associated with extremely long and productive blooms are contributing to the decline of those species. It has also been proposed that the low lake levels made possible by the construction of a dam at the outlet from the lake in 1921 have contributed to worsening water quality through a variety of possible mechanisms (Jacob Kann, Klamath Tribes, written com-mun., 1995). One such mechanism would be an increase in internal phosphorus loading from resuspended sediments (Jacoby and others, 1982), resulting from an increase in bottom shear stresses at lower lake levels (Laenen and LeTourneau, 1996), leading in turn to more intense algal blooms. Another possible mechanism is an earlier triggering of algal blooms. When early spring lake levels are low, greater light intensity at the sediment surface might speed recruitment of algal cells from the sediments. Sediment recruitment has been shown to be an important contributor to water column biomass increases in A. flos aquae (Barbiero and Kann, 1994) and Gloeotrichia echinulata (Barbiero, 1993). An earlier bloom could result in poor water quality conditions occurring earlier in the year, when young-of-the-year fish may be more susceptible to those conditions. Lake level can also influence water quality directly. An increased frequency of sediment resuspension at lower lake levels could increase chemical and biological oxygen demand, resulting in decreased dissolved oxygen concentrations. Sediment oxygen demand also may be enhanced at lower lake levels because it is concentrated over a smaller volume of water. Some compensation for increased oxygen demand at lower lake levels might be provided by increased reaeration, if the water column mixes from top to bottom more frequently. Based on the analysis of data that they have been collecting for several years, the Klamath Tribes recently recommended that the Bureau of Reclamation (Reclamation) modify the operating plan for the dam to make the minimum lake levels for the June-August period more closely resemble pre-dam conditions (Jacob Kann, written commun., 1995). The U.S. Geological Survey (USGS) was asked to analyze the available data for the lake and to assess whether the evidence exists to conclude that year-to-year differences in certain lake water-quality variables are related to year-to-year differences in lake level. The results of the analysis will be used as scientific input in the process of developing an operating plan for the Link River Dam. Datasets Two water-quality datasets were analyzed. The first was a series of hourly records of pH, dissolved oxygen, and water temperature, each of approximately a week's duration. The records were collected at 3 sites over 3 years, 1992 through 1994, with enough consistency to define the seasonal patterns. This dataset provided information about the diel extremes in dissolved oxygen and pH and the seasonal pattern in the diel cycle, but measurements were limited to a depth of 1 m(3.28 ft). The second dataset was a set of depth profiles of pH and dissolved oxygen and concurrent depth-integrated samples for nutrients and chlo-rophyll-a. The profiles were collected at approximately biweekly intervals at nine sites (seven in Upper Klamath and two in Agency Lake) over the 5 years 1990 through 1994. These depth profiles provided information on the depth-dependence of dissolved oxygen and pH, and allowed more extensive year-to-year comparisons than did the hourly records. Because measurements were made at each site only once during the sampling day, however, they did not capture the daily extremes in water quality. Lake level is measured daily by the USGS at three sites around the lake: Rocky Point, Rattlesnake Point, and near the city of Klamath Falls. These daily measurements are then used to compute a spatially weighted average of the lake level that is reported in the USGS annual Water-Data Report for Oregon. The average lake levels were used in this report. Two climatic datasets were used in this report; both were collected at the Klamath Falls airport. Air temperature was recorded as a daily maximum and daily minimum value. Cloud cover was quantized on a daily basis into one of seven levels. Because the focus of this study was primarily to examine possible relations between water quality and lake level, the lake level data provide an important context for the discussions that follow. Close

• 40. [Image] Influences of human activity on stream temperatures and existence of cold-water fish in streams with elevated temperature: report of a workshop: Independent Multidisciplinary Science Team, Corvallis, OR, October 5-6, 2000

  	Executive Summary The Independent Multidisciplinary Science Team (IMST) convened a panel of experts on stream temperature and fish ecology on October 5-6, 2000 for a scientific workshop on human influences ...
  	Citation × Citation Citation Abstract Copy Title: Influences of human activity on stream temperatures and existence of cold-water fish in streams with elevated temperature: report of a workshop: Independent Multidisciplinary Science Team, Corvallis, OR, October 5-6, 2000 Author: Independent Multidisciplinary Science Team (Oregon) Year: 2000, 2008, 2005 Executive Summary The Independent Multidisciplinary Science Team (IMST) convened a panel of experts on stream temperature and fish ecology on October 5-6, 2000 for a scientific workshop on human influences on stream temperature and responses by salmonids. The workshop was designed to review and discuss scientifically credible data and publications about 1) factors related to human activity that influence stream temperature and 2) behavioral, physical, and ecological mechanisms of cold water fish species for existing in streams with elevated temperatures. The goal of the workshop was to review empirical evidence and to identify points of agreement, disagreement, and knowledge gaps within the scientific community concerning the factors that influence stream temperature and fish responses to elevated temperatures. This information will assist the IMST in preparing a broader temperature report on Oregon's stream temperature water quality standards and their implementation. This report is prepared by the IMST. It was reviewed by workshop participants and revised by the IMST accordingly. The report includes abstracts of plenary presentations on factors that influence stream temperatures and fish responses, and the results of group discussions. The workshop participants focused on three main questions and were asked to list statements of agreement and disagreement, and to identify gaps in the scientific knowledge related to each question: ? How and where does riparian vegetation influence stream temperature? ? Do other changes in streams cause increases in stream temperature? ? How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? The workshop participants provided answers to the questions in the form of bullets. The answers below represent the IMST's summation of the workshop findings and were reviewed by the participants. Several gaps in the scientific basis for specific questions or relationships were identified. The participants found no areas of disagreement for which technical information was available. They noted that any disagreements were not related to scientific interpretation, but were based on concerns or opinions about application, regulation, and management. How and where does riparian vegetation influence stream temperature? The influence of riparian vegetation on stream temperature is cumulative and complex, varying by site, over time, and across regions. Riparian vegetation can directly affect stream temperature by intercepting solar radiation and reducing stream heating. The influence of riparian shade in controlling temperature declines as streams widen in downstream reaches, but the role of riparian vegetation in providing water quality and fish habitat benefits continues to be important. Besides providing shade, riparian vegetation can also indirectly affect stream temperature by influencing microclimate, affecting channel morphology, affecting stream flow, influencing wind speed, affecting humidity, affecting soil temperature, using water, influencing air temperature, enhancing infiltration, and influencing thermal radiation. It is critical to know the site potential to understand what vegetation a site can support. There is not a good scientific understanding of how much vegetation shading is required to affect stream temperature. 1 This lack of understanding may be due to the spatial and temporal variability in landscape components, and the resulting variability in both the direct and indirect influences of vegetation on stream temperature. Therefore, it is difficult to generalize about the effects of vegetation on stream temperature. Do other changes in streams cause increases in stream temperature? The answer to this question is yes, other physical changes in the stream system can modify stream temperatures. Stream temperature is a product of complex interactions between geomorphology, soil, hydrology, vegetation, and climate within a watershed. Changes in these factors will result in changes in stream temperature. Human activities influence stream temperature by affecting one or more of four major components: riparian vegetation, channel morphology, hydrology, and surface/subsurface interactions. Stream systems vary substantially across the landscape, and site-specific information is critical to understanding stream temperature responses to human activities. How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? Workshop participants identified several mechanisms that might explain the ability of fish populations to exist at higher than expected temperatures. The first mechanism was that the fish may have physiological adaptations to survive exposures to high temperatures. A second possibility was that stream habitats may contain cooler microhabitats that fish can occupy as refuge from higher temperatures. A third consideration is that ecological interactions may be different under differing thermal conditions resulting, for example, in changes in disease virulence or cumulative effects of stressors. Finally, since substantial differences exist between laboratory and field studies, it is difficult to apply results of laboratory studies to fish responses in the field. It is important to note that these proposed mechanisms are speculative and, as the list of gaps indicates, substantial experimental work is required to establish their influences on fish in different stream systems. Workshop Summaiy Workshop participants recognized gaps in the available science. Additional knowledge about human influences on stream temperatures and, consequently, influences on cold-water fish populations, will improve our ability to prevent further degradation of stream habitat and will enhance efforts geared towards the recovery of depressed fish populations. Even with these gaps, there was enough agreement on factors that influence stream temperature to indicate information is available to start developing and implementing management practices that are designed to reduce stream warming. It was suggested that managers should consider riparian vegetation, channel morphology, and hydrology, and should account for site differences. Title: Influences of human activity on stream temperatures and existence of cold-water fish in streams with elevated temperature: report of a workshop: Independent Multidisciplinary Science Team, Corvallis, OR, October 5-6, 2000 Author: Independent Multidisciplinary Science Team (Oregon) Year: 2000, 2008, 2005 Executive Summary The Independent Multidisciplinary Science Team (IMST) convened a panel of experts on stream temperature and fish ecology on October 5-6, 2000 for a scientific workshop on human influences on stream temperature and responses by salmonids. The workshop was designed to review and discuss scientifically credible data and publications about 1) factors related to human activity that influence stream temperature and 2) behavioral, physical, and ecological mechanisms of cold water fish species for existing in streams with elevated temperatures. The goal of the workshop was to review empirical evidence and to identify points of agreement, disagreement, and knowledge gaps within the scientific community concerning the factors that influence stream temperature and fish responses to elevated temperatures. This information will assist the IMST in preparing a broader temperature report on Oregon's stream temperature water quality standards and their implementation. This report is prepared by the IMST. It was reviewed by workshop participants and revised by the IMST accordingly. The report includes abstracts of plenary presentations on factors that influence stream temperatures and fish responses, and the results of group discussions. The workshop participants focused on three main questions and were asked to list statements of agreement and disagreement, and to identify gaps in the scientific knowledge related to each question: ? How and where does riparian vegetation influence stream temperature? ? Do other changes in streams cause increases in stream temperature? ? How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? The workshop participants provided answers to the questions in the form of bullets. The answers below represent the IMST's summation of the workshop findings and were reviewed by the participants. Several gaps in the scientific basis for specific questions or relationships were identified. The participants found no areas of disagreement for which technical information was available. They noted that any disagreements were not related to scientific interpretation, but were based on concerns or opinions about application, regulation, and management. How and where does riparian vegetation influence stream temperature? The influence of riparian vegetation on stream temperature is cumulative and complex, varying by site, over time, and across regions. Riparian vegetation can directly affect stream temperature by intercepting solar radiation and reducing stream heating. The influence of riparian shade in controlling temperature declines as streams widen in downstream reaches, but the role of riparian vegetation in providing water quality and fish habitat benefits continues to be important. Besides providing shade, riparian vegetation can also indirectly affect stream temperature by influencing microclimate, affecting channel morphology, affecting stream flow, influencing wind speed, affecting humidity, affecting soil temperature, using water, influencing air temperature, enhancing infiltration, and influencing thermal radiation. It is critical to know the site potential to understand what vegetation a site can support. There is not a good scientific understanding of how much vegetation shading is required to affect stream temperature. 1 This lack of understanding may be due to the spatial and temporal variability in landscape components, and the resulting variability in both the direct and indirect influences of vegetation on stream temperature. Therefore, it is difficult to generalize about the effects of vegetation on stream temperature. Do other changes in streams cause increases in stream temperature? The answer to this question is yes, other physical changes in the stream system can modify stream temperatures. Stream temperature is a product of complex interactions between geomorphology, soil, hydrology, vegetation, and climate within a watershed. Changes in these factors will result in changes in stream temperature. Human activities influence stream temperature by affecting one or more of four major components: riparian vegetation, channel morphology, hydrology, and surface/subsurface interactions. Stream systems vary substantially across the landscape, and site-specific information is critical to understanding stream temperature responses to human activities. How can apparently healthy fish populations exist in streams with temperatures higher than laboratory and field studies would indicate as healthy? Workshop participants identified several mechanisms that might explain the ability of fish populations to exist at higher than expected temperatures. The first mechanism was that the fish may have physiological adaptations to survive exposures to high temperatures. A second possibility was that stream habitats may contain cooler microhabitats that fish can occupy as refuge from higher temperatures. A third consideration is that ecological interactions may be different under differing thermal conditions resulting, for example, in changes in disease virulence or cumulative effects of stressors. Finally, since substantial differences exist between laboratory and field studies, it is difficult to apply results of laboratory studies to fish responses in the field. It is important to note that these proposed mechanisms are speculative and, as the list of gaps indicates, substantial experimental work is required to establish their influences on fish in different stream systems. Workshop Summaiy Workshop participants recognized gaps in the available science. Additional knowledge about human influences on stream temperatures and, consequently, influences on cold-water fish populations, will improve our ability to prevent further degradation of stream habitat and will enhance efforts geared towards the recovery of depressed fish populations. Even with these gaps, there was enough agreement on factors that influence stream temperature to indicate information is available to start developing and implementing management practices that are designed to reduce stream warming. It was suggested that managers should consider riparian vegetation, channel morphology, and hydrology, and should account for site differences. Close