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• 3711. [Image] Mainstem Klamath River fall chinook spawning Redd survey : fiscal year 1995 and 1996

  	ABSTRACT With the decreasing runs of natural fall chinook salmon* Oncorhmchus tshawytscha.inthe Klamath River basin, concerns were raised regarding the accuracy ma significance 01 me mainstem Klamath River ...
  	Citation × Citation Citation Abstract Copy Title: Mainstem Klamath River fall chinook spawning Redd survey : fiscal year 1995 and 1996 Author: Catalano, Mark Year: 1997, 2005 ABSTRACT With the decreasing runs of natural fall chinook salmon* Oncorhmchus tshawytscha.inthe Klamath River basin, concerns were raised regarding the accuracy ma significance 01 me mainstem Klamath River .1 chinook spawner estimates. The U.S. Fish and Wildlife Service, Coastal California Fish an - Wildlife Office (CCFWO) was funded through the Klamath River Fish and Wildlife Restoration Act (P. L.99-552) in the Fall of 1993-1996 to address this concern. The 1995 and 1996 survey season marked the third and fourth year that the CCFWO conducted investigations on the upper mainstem Klamath River to derive a reasonable estimate of natural * fall chinook spawners. A total of 339 redds were observed in the 1993 survey. In 1994 and 1995, redd counts increased to a total of 1,702 and 3,240 respectively. During the 1994 and 1995 spawning, seasons, there was evidence that unspawned surplus adult fall chinook salmon released from Iron Gate Hatchery (IGH) successfully spawned in the Klamath River. One hatchery fin clipped adult was observed spawning.30 miles downstream of the hatchery. In 1996, 1,372 redds were observed which wasa decrease of 43% from the previous year. There was complete retention of hatchery origin adults by IGH in 1996, although, the distribution of redds remained the same as previous years. With the new hatchery policy of excess return retention, mainstem escapement can now be considered a reasonable estimate of natural spawning adult chinook salmon. Reddsubstrate composition estimates remained consistent with previous spa- *:g survey data. Based upon 210 redd measurements from 1995-1996, the average redd size L ...e mainstem of the Klamath River was 9.6 nr. The average pit depth, mound depth, and adjacent depth for 1995-1996 was similar to previous survey results. Redds were most common along the wetted channel margins with numerous redds observed in side channels with suitable gravel and water velocities. Unlike 1993 and 1994 some redds were observed by 1995 and 1996 survey crews in rnid-channei areas. Recreational suction dredge mining was present throughout the survey from the confluence of Scott River downstream to the confluence of Indian Creek, although only two redds were observed on recent dredge tailings. Under the existing mining regulations, adverse impacts on redds could occur below the Scon River without protection of spawning areas. Title: Mainstem Klamath River fall chinook spawning Redd survey : fiscal year 1995 and 1996 Author: Catalano, Mark Year: 1997, 2005 ABSTRACT With the decreasing runs of natural fall chinook salmon* Oncorhmchus tshawytscha.inthe Klamath River basin, concerns were raised regarding the accuracy ma significance 01 me mainstem Klamath River .1 chinook spawner estimates. The U.S. Fish and Wildlife Service, Coastal California Fish an - Wildlife Office (CCFWO) was funded through the Klamath River Fish and Wildlife Restoration Act (P. L.99-552) in the Fall of 1993-1996 to address this concern. The 1995 and 1996 survey season marked the third and fourth year that the CCFWO conducted investigations on the upper mainstem Klamath River to derive a reasonable estimate of natural * fall chinook spawners. A total of 339 redds were observed in the 1993 survey. In 1994 and 1995, redd counts increased to a total of 1,702 and 3,240 respectively. During the 1994 and 1995 spawning, seasons, there was evidence that unspawned surplus adult fall chinook salmon released from Iron Gate Hatchery (IGH) successfully spawned in the Klamath River. One hatchery fin clipped adult was observed spawning.30 miles downstream of the hatchery. In 1996, 1,372 redds were observed which wasa decrease of 43% from the previous year. There was complete retention of hatchery origin adults by IGH in 1996, although, the distribution of redds remained the same as previous years. With the new hatchery policy of excess return retention, mainstem escapement can now be considered a reasonable estimate of natural spawning adult chinook salmon. Reddsubstrate composition estimates remained consistent with previous spa- *:g survey data. Based upon 210 redd measurements from 1995-1996, the average redd size L ...e mainstem of the Klamath River was 9.6 nr. The average pit depth, mound depth, and adjacent depth for 1995-1996 was similar to previous survey results. Redds were most common along the wetted channel margins with numerous redds observed in side channels with suitable gravel and water velocities. Unlike 1993 and 1994 some redds were observed by 1995 and 1996 survey crews in rnid-channei areas. Recreational suction dredge mining was present throughout the survey from the confluence of Scott River downstream to the confluence of Indian Creek, although only two redds were observed on recent dredge tailings. Under the existing mining regulations, adverse impacts on redds could occur below the Scon River without protection of spawning areas. Close

• 3712. [Image] Western water resource issues

  	CRS issue brief; "Updated May 19, 2005."
  	Citation × Citation Citation Abstract Copy Title: Western water resource issues Author: Cody, Betsy A.; Sheikh, Pervaze A. Year: 2005 CRS issue brief; "Updated May 19, 2005." Title: Western water resource issues Author: Cody, Betsy A.; Sheikh, Pervaze A. Year: 2005 CRS issue brief; "Updated May 19, 2005." Close

• 3713. [Image] Geology and ground-water resources of the Swan Lake-Yonna Valleys area, Klamath County, Oregon

  	Abstract The Swan Lake-Yonna Valleys area consists of two intermountain valleys with their subordinate side valleys adjoining slopes, and mountainous boundary ridges, In all the area covered is about 256 ...
  	Citation × Citation Citation Abstract Copy Title: Geology and ground-water resources of the Swan Lake-Yonna Valleys area, Klamath County, Oregon Author: Meyers, Joseph D. Year: 1952, 2007, 2005 Abstract The Swan Lake-Yonna Valleys area consists of two intermountain valleys with their subordinate side valleys adjoining slopes, and mountainous boundary ridges, In all the area covered is about 256 square miles but the essential agricultural sections are restricted to the floors of Swan Lake and Yonna valleys with their respective subsidiary extensions of Pine Flats and Alkali Lake flats, a valley-floor area totaling about 90 square miles The floors of Swan Lake Valley and Yonna Valley lie at an altitude of about U52OO feet but the mountainous boundary ridges rise generally to 6000 feeto Yonna Valley is largely drained to Lost River by Buck Creek but also in part to Alkali Lakeo Swan Lake Valley and Pine Flats have only internal drainage. The Swan Lake Valley floor is the top of a deep alluvial fill, while Yonna Valley floor is mainly an erosional surface sloping to lines of through drainage Precipitation is about lit inches annually on the valley floors 9 but must be much more, possibly 18 to 24 inches, on the higher parts of the drainage basins. The growing season is short and killing frosts do occur in late spring and early fall. The rock units forming the bedrock structure of the area are consolidated or semiconsolidated rocks of Tertiary age and are largely of volcanic-flow and volcanic-sedimentary originc They consist of three main elements, a lower lava-rock unit, a sedimentary and volcanic-sedimentary unit, and an upper lava-rock unito The unconsolidated deposits are the older alluvium of Quaternary (and in part of late-Tertiary) age and the younger alluvium of Quaternary age0 The bedrock is faulted and deformed particularly so along a northwest-southeast set of fault lines that have given a remarkable linearity to the topography. Unpublished records subject to revision Ground water occurs below a regional water table that slopes south-ward to the level of the Lost Rivero The upper lava rocks and the lower lava rocks contain the principal permeable zones that occur beneath the areao Breccia and other porous zones in those rocks in places yield water to wells at a rate as large as 35OOO gallons per minute with but 1 or 2 feet of drawdowno The economical construction of irrigation wells requires the determination of the best possible location at which those rocks may be tapped at shallow depth below the level of the water tableo The ground water in general relatively low in dissolved mineral matter and is but slightly to moderately hard and would be considered chemically satisfactory for most uaeso Irrigation is the principal use of the ground water in the area north of the Horsefly Irrigation Districto There 3? wells supplied about 6,000 acre-feet of water to about 3800 acres of land in 1950. Water-level records obtained since 19U8 and approximations of the probable annual recharge from precipitation indicate that the present withdrawals are considerably less than the annual increment of the ground-water recharge, Rough estimates indicate that an increase in withdrawals of as much as 100 percent or more can take place before ground-water levels, by a persistent lowering, will begin to indicate that the annual replenishment is being exceeded. Title: Geology and ground-water resources of the Swan Lake-Yonna Valleys area, Klamath County, Oregon Author: Meyers, Joseph D. Year: 1952, 2007, 2005 Abstract The Swan Lake-Yonna Valleys area consists of two intermountain valleys with their subordinate side valleys adjoining slopes, and mountainous boundary ridges, In all the area covered is about 256 square miles but the essential agricultural sections are restricted to the floors of Swan Lake and Yonna valleys with their respective subsidiary extensions of Pine Flats and Alkali Lake flats, a valley-floor area totaling about 90 square miles The floors of Swan Lake Valley and Yonna Valley lie at an altitude of about U52OO feet but the mountainous boundary ridges rise generally to 6000 feeto Yonna Valley is largely drained to Lost River by Buck Creek but also in part to Alkali Lakeo Swan Lake Valley and Pine Flats have only internal drainage. The Swan Lake Valley floor is the top of a deep alluvial fill, while Yonna Valley floor is mainly an erosional surface sloping to lines of through drainage Precipitation is about lit inches annually on the valley floors 9 but must be much more, possibly 18 to 24 inches, on the higher parts of the drainage basins. The growing season is short and killing frosts do occur in late spring and early fall. The rock units forming the bedrock structure of the area are consolidated or semiconsolidated rocks of Tertiary age and are largely of volcanic-flow and volcanic-sedimentary originc They consist of three main elements, a lower lava-rock unit, a sedimentary and volcanic-sedimentary unit, and an upper lava-rock unito The unconsolidated deposits are the older alluvium of Quaternary (and in part of late-Tertiary) age and the younger alluvium of Quaternary age0 The bedrock is faulted and deformed particularly so along a northwest-southeast set of fault lines that have given a remarkable linearity to the topography. Unpublished records subject to revision Ground water occurs below a regional water table that slopes south-ward to the level of the Lost Rivero The upper lava rocks and the lower lava rocks contain the principal permeable zones that occur beneath the areao Breccia and other porous zones in those rocks in places yield water to wells at a rate as large as 35OOO gallons per minute with but 1 or 2 feet of drawdowno The economical construction of irrigation wells requires the determination of the best possible location at which those rocks may be tapped at shallow depth below the level of the water tableo The ground water in general relatively low in dissolved mineral matter and is but slightly to moderately hard and would be considered chemically satisfactory for most uaeso Irrigation is the principal use of the ground water in the area north of the Horsefly Irrigation Districto There 3? wells supplied about 6,000 acre-feet of water to about 3800 acres of land in 1950. Water-level records obtained since 19U8 and approximations of the probable annual recharge from precipitation indicate that the present withdrawals are considerably less than the annual increment of the ground-water recharge, Rough estimates indicate that an increase in withdrawals of as much as 100 percent or more can take place before ground-water levels, by a persistent lowering, will begin to indicate that the annual replenishment is being exceeded. Close

• 3714. [Image] Klamath River fish die-off, September 2002 : causative factors of mortality

  	Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath ...
  	Citation × Citation Citation Abstract Copy Title: Klamath River fish die-off, September 2002 : causative factors of mortality Author: Guillen, George Year: 2003, 2005, 2004 Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath River, California in September 2002. The proximate cause of death was heavy infections of two fish pathogens, Ich and columnaris. However, given that these ubiquitous pathogens are normally found in the Klamath River, additional factors must have played a role for them to have become lethal. It is our conclusion based on multiple lines of evidence that the fish die-off in the lower Klamath River in 2002 was a result of a combination of factors that began with an early peak in the return of a large run of fall Chinook salmon. Low river discharges apparently did not provide suitable attraction flows for migrating adult salmon, resulting in large numbers of fish congregating in the warm waters of the lower River. The high density offish, low discharges, warm water temperatures, and possible extended residence time of salmon created optimal conditions for parasite proliferation and precipitated an epizootic of Ich and columnaris. Based on a review of available literature and historical records, this was the largest known pre-spawning adult salmonid die-off recorded for the Klamath River and possibly the Pacific coast. Title: Klamath River fish die-off, September 2002 : causative factors of mortality Author: Guillen, George Year: 2003, 2005, 2004 Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath River, California in September 2002. The proximate cause of death was heavy infections of two fish pathogens, Ich and columnaris. However, given that these ubiquitous pathogens are normally found in the Klamath River, additional factors must have played a role for them to have become lethal. It is our conclusion based on multiple lines of evidence that the fish die-off in the lower Klamath River in 2002 was a result of a combination of factors that began with an early peak in the return of a large run of fall Chinook salmon. Low river discharges apparently did not provide suitable attraction flows for migrating adult salmon, resulting in large numbers of fish congregating in the warm waters of the lower River. The high density offish, low discharges, warm water temperatures, and possible extended residence time of salmon created optimal conditions for parasite proliferation and precipitated an epizootic of Ich and columnaris. Based on a review of available literature and historical records, this was the largest known pre-spawning adult salmonid die-off recorded for the Klamath River and possibly the Pacific coast. Close

• 3715. [Image] Biological assessment of Klamath Project's continuing operations on the endangered Lost River sucker and shortnose sucker

  	BIOLOGICAL ASSESSMENT OF KLAMATH PROJECT'S CONTINUING OPERATIONS ON THE ENDANGERED LOST RIVER SUCKER AND SHORTNOSE SUCKER U.S. Bureau of Reclamation Mid-Pacific Region Klamath Basin Area Office Klamath ...
  	Citation × Citation Citation Abstract Copy Title: Biological assessment of Klamath Project's continuing operations on the endangered Lost River sucker and shortnose sucker Author: United States. Bureau of Reclamation Year: 2001, 2005 BIOLOGICAL ASSESSMENT OF KLAMATH PROJECT'S CONTINUING OPERATIONS ON THE ENDANGERED LOST RIVER SUCKER AND SHORTNOSE SUCKER U.S. Bureau of Reclamation Mid-Pacific Region Klamath Basin Area Office Klamath Falls, Oregon February 13,2001 TABLE OF CONTENTS 1.0 INTRODUCTION 2 2.0 DESCRIPTION OF THE ACTION 3 3.0 DESCRIPTION OF HISTORIC OPERATIONS 6 4.0 ENDANGERED SPECIES POTENTIALLY AFFECTED BY THE KLAMATH PROJECT 16 5.0 ENVIRONMENTAL BASELINE 60 6.0 EFFECTS OF KLAMATH PROJECT ON BALD EAGLES 60 7.0 EFFECTS OF KLAMATH PROJECT ENDANGERED SUCKERS 63 8.0 PROPOSED CRITICAL HABITAT FOR ENDANGERED SUCKERS 82 9.0 CUMULATIVE EFFECTS 84 10.0 DETERMINATION OF EFFECTS 89 11.0 LITERATURE CITED 90 12.0 PERSONAL COMMUNICATIONS 100 13.0 APPENDIX 1 - ESA CONSULTATION REVIEW 101 Title: Biological assessment of Klamath Project's continuing operations on the endangered Lost River sucker and shortnose sucker Author: United States. Bureau of Reclamation Year: 2001, 2005 BIOLOGICAL ASSESSMENT OF KLAMATH PROJECT'S CONTINUING OPERATIONS ON THE ENDANGERED LOST RIVER SUCKER AND SHORTNOSE SUCKER U.S. Bureau of Reclamation Mid-Pacific Region Klamath Basin Area Office Klamath Falls, Oregon February 13,2001 TABLE OF CONTENTS 1.0 INTRODUCTION 2 2.0 DESCRIPTION OF THE ACTION 3 3.0 DESCRIPTION OF HISTORIC OPERATIONS 6 4.0 ENDANGERED SPECIES POTENTIALLY AFFECTED BY THE KLAMATH PROJECT 16 5.0 ENVIRONMENTAL BASELINE 60 6.0 EFFECTS OF KLAMATH PROJECT ON BALD EAGLES 60 7.0 EFFECTS OF KLAMATH PROJECT ENDANGERED SUCKERS 63 8.0 PROPOSED CRITICAL HABITAT FOR ENDANGERED SUCKERS 82 9.0 CUMULATIVE EFFECTS 84 10.0 DETERMINATION OF EFFECTS 89 11.0 LITERATURE CITED 90 12.0 PERSONAL COMMUNICATIONS 100 13.0 APPENDIX 1 - ESA CONSULTATION REVIEW 101 Close

• 3716. [Image] Histopathological changes in gills of Lost River suckers (Deltistes luxatus) exposed to elevated ammonia and elevated pH

  	Lease, Hilary M., Histopathological Changes in Gills of Lost River Suckers (Deltistes luxatus) Exposed to Elevated Ammonia and Elevated pH, M.S., Department of Zoology and Physiology, December, 2000. ...
  	Citation × Citation Citation Abstract Copy Title: Histopathological changes in gills of Lost River suckers (Deltistes luxatus) exposed to elevated ammonia and elevated pH Author: Lease, Hilary Marian Year: 2000, 2008, 2005 Lease, Hilary M., Histopathological Changes in Gills of Lost River Suckers (Deltistes luxatus) Exposed to Elevated Ammonia and Elevated pH, M.S., Department of Zoology and Physiology, December, 2000. The Lost River sucker {Deltistes luxatus) is a federally listed, endangered fish species endemic to Upper Klamath Lake?a large, shallow hypereutrophic lake in southern Oregon. Sucker population declines in the lake over the past few decades are thought to be partly attributable to extreme water quality conditions, including elevated ammonia concentrations and elevated pH, that occur during summer cyanobacterial blooms. I analyzed structural changes in gills of larval Lost River suckers after they were exposed to elevated pH and elevated ammonia concentrations in chronic toxicity tests conducted in the laboratory. Histopathological changes in sucker lamellae were observed at ammonia concentrations that did not significantly decrease survival, growth, whole-body ion content, or swimming performance. Structural changes that I evaluated included O2 diffusion distance, lamellar thickness, hyperplasic and hypertrophic mucous cells, and infiltration of white blood cells into the lymphatic space. The increases in diffusion distance and lamellar thickness were statistically significant (P < 0.05). These gill changes are indicative of potentially compromised respiratory and ionoregulatory capacity. Because in this species gill structural changes appear to be a more sensitive indicator of stress in eutrophic water quality conditions than are the more traditional sublethal indices, gill histopathology might be useful for monitoring the health of Lost River suckers in Upper Klamath Lake. Title: Histopathological changes in gills of Lost River suckers (Deltistes luxatus) exposed to elevated ammonia and elevated pH Author: Lease, Hilary Marian Year: 2000, 2008, 2005 Lease, Hilary M., Histopathological Changes in Gills of Lost River Suckers (Deltistes luxatus) Exposed to Elevated Ammonia and Elevated pH, M.S., Department of Zoology and Physiology, December, 2000. The Lost River sucker {Deltistes luxatus) is a federally listed, endangered fish species endemic to Upper Klamath Lake?a large, shallow hypereutrophic lake in southern Oregon. Sucker population declines in the lake over the past few decades are thought to be partly attributable to extreme water quality conditions, including elevated ammonia concentrations and elevated pH, that occur during summer cyanobacterial blooms. I analyzed structural changes in gills of larval Lost River suckers after they were exposed to elevated pH and elevated ammonia concentrations in chronic toxicity tests conducted in the laboratory. Histopathological changes in sucker lamellae were observed at ammonia concentrations that did not significantly decrease survival, growth, whole-body ion content, or swimming performance. Structural changes that I evaluated included O2 diffusion distance, lamellar thickness, hyperplasic and hypertrophic mucous cells, and infiltration of white blood cells into the lymphatic space. The increases in diffusion distance and lamellar thickness were statistically significant (P < 0.05). These gill changes are indicative of potentially compromised respiratory and ionoregulatory capacity. Because in this species gill structural changes appear to be a more sensitive indicator of stress in eutrophic water quality conditions than are the more traditional sublethal indices, gill histopathology might be useful for monitoring the health of Lost River suckers in Upper Klamath Lake. Close

• 3717. [Image] Endangered species : Fish and Wildlife Service generally focuses recovery funding on high priority species, but needs to periodically assess its funding decisions : report to the Chairman, Committee on Resources, House of Representatives

  	"GAO-05-211"; "April 2005"
  	Citation × Citation Citation Abstract Copy Title: Endangered species : Fish and Wildlife Service generally focuses recovery funding on high priority species, but needs to periodically assess its funding decisions : report to the Chairman, Committee on Resources, House of Representatives Author: U.S. Fish and Wildlife Service Year: 2005 "GAO-05-211"; "April 2005" Title: Endangered species : Fish and Wildlife Service generally focuses recovery funding on high priority species, but needs to periodically assess its funding decisions : report to the Chairman, Committee on Resources, House of Representatives Author: U.S. Fish and Wildlife Service Year: 2005 "GAO-05-211"; "April 2005" Close

• 3718. [Image] Reproductive biology and demographics of endangered Lost River and shortnose suckers in Upper Klamath Lake, Oregon

  	We analyzed the reproductive biology and demographics of the Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris, two endangered species endemic to the upper Klamath Basin ...
  	Citation × Citation Citation Abstract Copy Title: Reproductive biology and demographics of endangered Lost River and shortnose suckers in Upper Klamath Lake, Oregon Author: Perkins, David L.; Scoppettone, Gary; Buettner, Mark Year: 2000, 2005 We analyzed the reproductive biology and demographics of the Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris, two endangered species endemic to the upper Klamath Basin of Oregon and California, from 1984-1997. Lost River suckers had distinct river and lake shoreline spawning stocks, and individuals of both species commonly spawned in consecutive years. In the Williamson River and lower Sprague River, spawning migration by both species occurred mainly during a 5-week period that started within the first three weeks of April and peaked between mid April and early May, although a separate, earlier (mid March) run of Lost River suckers may also spawn in the upper Sprague River. Migration of both species was several times higher at dawn (0500-0730 h) and evening (1800-2200 h) than other times of the day. Peak migrations almost always corresponded to peaks in water temperature, usually at 10-15°C. Lost River suckers were captured at springs along the east shore of the lake from late February through mid May, with peak spawning usually in mid March to mid April. Shortnose suckers were generally captured at the springs from late March through late May, but the time of peak spawning was not determined. Size and age at maturity was determined by recruitment from a strong year class (1991). Male Lost River suckers began recruitment into the adult population at age 4+ (375-475 mm). Substantial recruitment of females did not begin until age 7+ (510-560 mm). Male and female shortnose suckers began recruitment at age 4+, with the majority offish recruited by age 5+. Males recruited at 270-370 mm; females recruited at 325-425 mm. Fecundity estimates were quite variable ranging from 44,000-236,000 eggs per female Lost River sucker and 18,000-72,000 eggs per female shortnose sucker. In 1984 and 1985, the spawning populations of both species were dominated by large, old individuals, with little indication of recent adult recruitment. In the next 13 years, only one strong year class (1991) recruited into the spawning populations of both species. This year class temporarily boosted population numbers, but annual fish kills from 1995 to 1997 eliminated most adults of both species. Associated with poor water quality caused by the proliferation and decay of blue-green algae Aphanizomenonflos-aquae, these fish kills raise concern that alterations to the lake ecosystem over the past several decades have Perkins et al. Lost River and shortnose suckers 5 increased the magnitude and frequency of poor water quality. As a result, mortality rates of all life stages may have increased, thereby disrupting the species' life history pattern and potentially decreasing long-term population viability. Introduction The Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris are large, long-lived suckers endemic to the upper Klamath Basin of Oregon and California. Both species are typically lake dwelling but migrate to tributaries or shoreline springs to spawn (Moyle 1976, Scoppettone and Vinyard 1991). Once extremely abundant (Cope 1884, Gilbert 1898), both species have experienced severe population declines and were federally listed as endangered in 1988 (USFWS 1988). Much of the original habitat of these suckers has been destroyed or altered by conversion of lake areas to agriculture, dams, instream flow diversions, and water quality problems associated with timber harvest, loss of riparian vegetation, livestock grazing, and agricultural practices (USFWS 1988). Knowledge of the life history of Lost River and shortnose suckers is fundamental to recovery of these species. The objective of this report was to present the results of studies conducted from 1987-1998 on the reproductive biology and demographics of Lost River and shortnose suckers, and to compare these results with earlier unpublished data. Study Sites Studies were conducted on Upper Klamath Lake and the lower Williamson-Sprague river system (Figure 1). These waters form the upper portion of the Klamath River Basin in south-central Oregon and represent most remaining native habitat of Lost River and shortnose suckers. Upper Klamath Lake is a remnant of pluvial Lake Modoc that included eight major basins and encompassed 2,839 km2 (Dicken 1980). Today, Upper Klamath Lake serves as a storage reservoir that provides water for agricultural irrigation, waterfowl refuges, instream flow requirements of anadromous fish, and hydroelectric power generation. At full capacity, the lake covers approximately 360 km2 and has an average depth of 2.4 m. Most deeper water (3-12 m) is restricted to narrow trenches along the western shore. Lake elevation is controlled at the outlet by Link River Title: Reproductive biology and demographics of endangered Lost River and shortnose suckers in Upper Klamath Lake, Oregon Author: Perkins, David L.; Scoppettone, Gary; Buettner, Mark Year: 2000, 2005 We analyzed the reproductive biology and demographics of the Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris, two endangered species endemic to the upper Klamath Basin of Oregon and California, from 1984-1997. Lost River suckers had distinct river and lake shoreline spawning stocks, and individuals of both species commonly spawned in consecutive years. In the Williamson River and lower Sprague River, spawning migration by both species occurred mainly during a 5-week period that started within the first three weeks of April and peaked between mid April and early May, although a separate, earlier (mid March) run of Lost River suckers may also spawn in the upper Sprague River. Migration of both species was several times higher at dawn (0500-0730 h) and evening (1800-2200 h) than other times of the day. Peak migrations almost always corresponded to peaks in water temperature, usually at 10-15°C. Lost River suckers were captured at springs along the east shore of the lake from late February through mid May, with peak spawning usually in mid March to mid April. Shortnose suckers were generally captured at the springs from late March through late May, but the time of peak spawning was not determined. Size and age at maturity was determined by recruitment from a strong year class (1991). Male Lost River suckers began recruitment into the adult population at age 4+ (375-475 mm). Substantial recruitment of females did not begin until age 7+ (510-560 mm). Male and female shortnose suckers began recruitment at age 4+, with the majority offish recruited by age 5+. Males recruited at 270-370 mm; females recruited at 325-425 mm. Fecundity estimates were quite variable ranging from 44,000-236,000 eggs per female Lost River sucker and 18,000-72,000 eggs per female shortnose sucker. In 1984 and 1985, the spawning populations of both species were dominated by large, old individuals, with little indication of recent adult recruitment. In the next 13 years, only one strong year class (1991) recruited into the spawning populations of both species. This year class temporarily boosted population numbers, but annual fish kills from 1995 to 1997 eliminated most adults of both species. Associated with poor water quality caused by the proliferation and decay of blue-green algae Aphanizomenonflos-aquae, these fish kills raise concern that alterations to the lake ecosystem over the past several decades have Perkins et al. Lost River and shortnose suckers 5 increased the magnitude and frequency of poor water quality. As a result, mortality rates of all life stages may have increased, thereby disrupting the species' life history pattern and potentially decreasing long-term population viability. Introduction The Lost River sucker Deltistes luxatus and shortnose sucker Chasmistes brevirostris are large, long-lived suckers endemic to the upper Klamath Basin of Oregon and California. Both species are typically lake dwelling but migrate to tributaries or shoreline springs to spawn (Moyle 1976, Scoppettone and Vinyard 1991). Once extremely abundant (Cope 1884, Gilbert 1898), both species have experienced severe population declines and were federally listed as endangered in 1988 (USFWS 1988). Much of the original habitat of these suckers has been destroyed or altered by conversion of lake areas to agriculture, dams, instream flow diversions, and water quality problems associated with timber harvest, loss of riparian vegetation, livestock grazing, and agricultural practices (USFWS 1988). Knowledge of the life history of Lost River and shortnose suckers is fundamental to recovery of these species. The objective of this report was to present the results of studies conducted from 1987-1998 on the reproductive biology and demographics of Lost River and shortnose suckers, and to compare these results with earlier unpublished data. Study Sites Studies were conducted on Upper Klamath Lake and the lower Williamson-Sprague river system (Figure 1). These waters form the upper portion of the Klamath River Basin in south-central Oregon and represent most remaining native habitat of Lost River and shortnose suckers. Upper Klamath Lake is a remnant of pluvial Lake Modoc that included eight major basins and encompassed 2,839 km2 (Dicken 1980). Today, Upper Klamath Lake serves as a storage reservoir that provides water for agricultural irrigation, waterfowl refuges, instream flow requirements of anadromous fish, and hydroelectric power generation. At full capacity, the lake covers approximately 360 km2 and has an average depth of 2.4 m. Most deeper water (3-12 m) is restricted to narrow trenches along the western shore. Lake elevation is controlled at the outlet by Link River Close

• 3719. [Image] Annual report, Klamath River fisheries assessment program : juvenile salmonid trapping on the mainstem Trinity River at Willow Creek and on the Klamath River at Big Bar, 1990

  	ABSTRACT This report details the third year of Klamath River basin juvenile salmonid fishery investigations and represents the second year of sampling with rotary screw traps. Two traps, positioned side ...
  	Citation × Citation Citation Abstract Copy Title: Annual report, Klamath River fisheries assessment program : juvenile salmonid trapping on the mainstem Trinity River at Willow Creek and on the Klamath River at Big Bar, 1990 Author: Craig, James L. Year: 1992, 2005 ABSTRACT This report details the third year of Klamath River basin juvenile salmonid fishery investigations and represents the second year of sampling with rotary screw traps. Two traps, positioned side to side, were used at both the Klamath and Trinity River sites. The traps on the Klamath River were located at Big Bar (rkm 81) and began operation in March. The traps operated until July 10 and 18 sampling 38 and 31 nights respectively. Combined catch included 333 chinook (Oncorhynchus tshawytscha) , 178 steelhead (O^ mykiss) , and 30 coho (O^ kisutch) . No appreciable difference in mean catch or mean fork length of catch between the two traps was found. Peak weekly chinook catch effort, as an indicator of peak emigration, occurred the week of June 18 to 24. A total of five (1.5%) Ad-clip chinook were captured. A contribution of 134 (40%) hatchery chinook and 199 (60%) natural stock chinook was estimated for the total chinook captured. Mean migration rate for IGH Ad-clip chinook was 5. Title: Annual report, Klamath River fisheries assessment program : juvenile salmonid trapping on the mainstem Trinity River at Willow Creek and on the Klamath River at Big Bar, 1990 Author: Craig, James L. Year: 1992, 2005 ABSTRACT This report details the third year of Klamath River basin juvenile salmonid fishery investigations and represents the second year of sampling with rotary screw traps. Two traps, positioned side to side, were used at both the Klamath and Trinity River sites. The traps on the Klamath River were located at Big Bar (rkm 81) and began operation in March. The traps operated until July 10 and 18 sampling 38 and 31 nights respectively. Combined catch included 333 chinook (Oncorhynchus tshawytscha) , 178 steelhead (O^ mykiss) , and 30 coho (O^ kisutch) . No appreciable difference in mean catch or mean fork length of catch between the two traps was found. Peak weekly chinook catch effort, as an indicator of peak emigration, occurred the week of June 18 to 24. A total of five (1.5%) Ad-clip chinook were captured. A contribution of 134 (40%) hatchery chinook and 199 (60%) natural stock chinook was estimated for the total chinook captured. Mean migration rate for IGH Ad-clip chinook was 5. Close

• 3720. [Image] Proceedings of second conference of engineers of the Reclamation service, with accompanying papers.

  	Conference was held at El Paso, Tex., November 14 to 18, 1904, and adjourned to Washington, D.C., where it was continued from January 9 to 14, 1905;
  	Citation × Citation Citation Abstract Copy Title: Proceedings of second conference of engineers of the Reclamation service, with accompanying papers. Author: Newell, Frederick Haynes, 1862-1932 Year: 1905, 2008, 2005 Conference was held at El Paso, Tex., November 14 to 18, 1904, and adjourned to Washington, D.C., where it was continued from January 9 to 14, 1905; Title: Proceedings of second conference of engineers of the Reclamation service, with accompanying papers. Author: Newell, Frederick Haynes, 1862-1932 Year: 1905, 2008, 2005 Conference was held at El Paso, Tex., November 14 to 18, 1904, and adjourned to Washington, D.C., where it was continued from January 9 to 14, 1905; Close