Search

Search Results

• 81. [Article] Native Trout Studies, Annual Progress Report, Project # F-136-R-12

  Abstract -- During 1999, we operated traps to capture upstream and downstream migrant westslope cutthroat trout in the upper mainstem John Day River and three of its tributaries. We also operated a rotary ...

  Citation × Citation Citation Abstract Copy Title: Native Trout Studies, Annual Progress Report, Project # F-136-R-12 Abstract -- During 1999, we operated traps to capture upstream and downstream migrant westslope cutthroat trout in the upper mainstem John Day River and three of its tributaries. We also operated a rotary screw trap in the John Day River downstream of all tributary traps. These traps were operated from May throughout the contract period. A total of 94 westslope cutthroat trout were captured in all traps, ranging in size from 7 to 39 cm. The screw trap also captured 4,014 fish of six other species. We continued to track cutthroat trout with radio tags implanted in 1998 throughout the life of the tags. These fish displayed a variety of movements, including fluvial migrations from Roberts Creek into the mainstem John Day River, localized movements, and a suggestion of extensive movement. We prepared a draft report of that summarizes information about westslope cutthroat trout in the John Day Basin. We helped determine the distribution and abundance of bull trout and sympatric rainbow trout in four streams of the Middle Fork John Day River. Title: Native Trout Studies, Annual Progress Report, Project # F-136-R-12 Abstract -- During 1999, we operated traps to capture upstream and downstream migrant westslope cutthroat trout in the upper mainstem John Day River and three of its tributaries. We also operated a rotary screw trap in the John Day River downstream of all tributary traps. These traps were operated from May throughout the contract period. A total of 94 westslope cutthroat trout were captured in all traps, ranging in size from 7 to 39 cm. The screw trap also captured 4,014 fish of six other species. We continued to track cutthroat trout with radio tags implanted in 1998 throughout the life of the tags. These fish displayed a variety of movements, including fluvial migrations from Roberts Creek into the mainstem John Day River, localized movements, and a suggestion of extensive movement. We prepared a draft report of that summarizes information about westslope cutthroat trout in the John Day Basin. We helped determine the distribution and abundance of bull trout and sympatric rainbow trout in four streams of the Middle Fork John Day River. Close

• 82. [Article] Trout in Running Waters 1994 - Draft

  Abstract -- This chapter covers management of resident trout species in the Rogue, Applegate, and Illinois rivers and all associated tributary streams (running waters) of the Rogue River basin. Resident ...

  Citation × Citation Citation Abstract Copy Title: Trout in Running Waters 1994 - Draft Abstract -- This chapter covers management of resident trout species in the Rogue, Applegate, and Illinois rivers and all associated tributary streams (running waters) of the Rogue River basin. Resident rainbow and resident, fluvial, and anadromous cutthroat trout are native to the Rogue River basin. Angling for trout in the Rogue River basin did not become popular until the 1930s. At this time, cutthroat and downstream migrating steelhead were abundant and easily caught from streams in settled areas of the Rogue basin. Mining roads provided easy access to the headwaters of the Applegate and Illinois rivers, Jumpoff Joe creek, and Grave creek where trout fishing was most popular. The California-Oregon Power Company developed roads that provided access to trout fishing waters in the Prospect area in 1912 and the upper Rogue River and its tributaries became accessible in 1927 when the Crater Lake Highway was completed. The Civil Conservation corps developed foot paths and roads into remote parts of the basin in the 1930s. Trout fishing in high pressure areas in the Rogue basin is maintained by stocking. A list of species and numbers of hatchery fish stocked in running waters of the Rogue River basin is presented in Appendix Table A-4. Title: Trout in Running Waters 1994 - Draft Abstract -- This chapter covers management of resident trout species in the Rogue, Applegate, and Illinois rivers and all associated tributary streams (running waters) of the Rogue River basin. Resident rainbow and resident, fluvial, and anadromous cutthroat trout are native to the Rogue River basin. Angling for trout in the Rogue River basin did not become popular until the 1930s. At this time, cutthroat and downstream migrating steelhead were abundant and easily caught from streams in settled areas of the Rogue basin. Mining roads provided easy access to the headwaters of the Applegate and Illinois rivers, Jumpoff Joe creek, and Grave creek where trout fishing was most popular. The California-Oregon Power Company developed roads that provided access to trout fishing waters in the Prospect area in 1912 and the upper Rogue River and its tributaries became accessible in 1927 when the Crater Lake Highway was completed. The Civil Conservation corps developed foot paths and roads into remote parts of the basin in the 1930s. Trout fishing in high pressure areas in the Rogue basin is maintained by stocking. A list of species and numbers of hatchery fish stocked in running waters of the Rogue River basin is presented in Appendix Table A-4. Close

• 83. [Article] Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss Author: Schreck, Carl B., Noakes, David L.G., Yada, Takashi, Matsuda, Hiroyuki, Miura, Go, Munakata, Arimune To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Title: Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss Author: Schreck, Carl B., Noakes, David L.G., Yada, Takashi, Matsuda, Hiroyuki, Miura, Go, Munakata, Arimune To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/. Close

• 84. [Article] Increasing Thiamine Concentrations in Lake Trout Eggs from Lakes Huron and Michigan Coincide with Low Alewife Abundance

  Lake trout Salvelinus namaycush in the Laurentian Great Lakes suffer from thiamine deficiency as a result of adult lake trout consuming prey containing thiaminase, a thiamine-degrading enzyme. Sufficiently ...

  Citation × Citation Citation Abstract Copy Title: Increasing Thiamine Concentrations in Lake Trout Eggs from Lakes Huron and Michigan Coincide with Low Alewife Abundance Author: Riley, Stephen C., Evans, Allison N., Honeyfield, Dale C., Rinchard, Jacques, Begnoche, Linda Lake trout Salvelinus namaycush in the Laurentian Great Lakes suffer from thiamine deficiency as a result of adult lake trout consuming prey containing thiaminase, a thiamine-degrading enzyme. Sufficiently low egg thiamine concentrations result in direct mortality of or sublethal effects on newly hatched lake trout fry. To determine the prevalence and severity of low thiamine in lake trout eggs, we monitored thiamine concentrations in lake trout eggs from 15 sites in Lakes Huron and Michigan from 2001 to 2009. Lake trout egg thiamine concentrations at most sites in both lakes were initially low and increased over time at 11 of 15 sites, and the proportion of females with egg thiamine concentrations lower than the recommended management objective of 4 nmol/g decreased over time at eight sites. Egg thiamine concentrations at five of six sites in Lakes Huron and Michigan were significantly inversely related to site-specific estimates of mean abundance of alewives Alosa pseudoharengus, and successful natural reproduction of lake trout has been observed in Lake Huron since the alewife population crashed. These results support the hypothesis that low egg thiamine in Great Lakes lake trout is associated with increased alewife abundance and that low alewife abundance may currently be a prerequisite for successful reproduction by lake trout in the Great Lakes. Title: Increasing Thiamine Concentrations in Lake Trout Eggs from Lakes Huron and Michigan Coincide with Low Alewife Abundance Author: Riley, Stephen C., Evans, Allison N., Honeyfield, Dale C., Rinchard, Jacques, Begnoche, Linda Lake trout Salvelinus namaycush in the Laurentian Great Lakes suffer from thiamine deficiency as a result of adult lake trout consuming prey containing thiaminase, a thiamine-degrading enzyme. Sufficiently low egg thiamine concentrations result in direct mortality of or sublethal effects on newly hatched lake trout fry. To determine the prevalence and severity of low thiamine in lake trout eggs, we monitored thiamine concentrations in lake trout eggs from 15 sites in Lakes Huron and Michigan from 2001 to 2009. Lake trout egg thiamine concentrations at most sites in both lakes were initially low and increased over time at 11 of 15 sites, and the proportion of females with egg thiamine concentrations lower than the recommended management objective of 4 nmol/g decreased over time at eight sites. Egg thiamine concentrations at five of six sites in Lakes Huron and Michigan were significantly inversely related to site-specific estimates of mean abundance of alewives Alosa pseudoharengus, and successful natural reproduction of lake trout has been observed in Lake Huron since the alewife population crashed. These results support the hypothesis that low egg thiamine in Great Lakes lake trout is associated with increased alewife abundance and that low alewife abundance may currently be a prerequisite for successful reproduction by lake trout in the Great Lakes. Close

• 85. [Article] Acute and chronic toxicity studies with monochlorobenzene in rainbow trout

  The toxicity of chlorobenzene (CB) was investigated in rainbow trout following acute ip administration (1. 0 ml/kg, 1:1 in corn oil) and chronic exposure (2. 1 ppm and 2. 9 ppm) via the water in a continuously flowing ...

  Citation × Citation Citation Abstract Copy Title: Acute and chronic toxicity studies with monochlorobenzene in rainbow trout Author: Dalich, George M. The toxicity of chlorobenzene (CB) was investigated in rainbow trout following acute ip administration (1. 0 ml/kg, 1:1 in corn oil) and chronic exposure (2. 1 ppm and 2. 9 ppm) via the water in a continuously flowing system for 15 and 30 days. In the acute study, overt toxicity and hepatotoxicity were monitored over a 96 hour time period. Variables measured to assess toxicity included LD50 determination, weight changes, liver weight to body weight ratios, behavioral changes, alanine aminotransferase activity (GPT), sulfobromophthalein (BSP) retention, total plasma protein concentration and liver histopathology. In the chronic study the same measures of toxicity were followed as well as respiratory rates, oxygen consumption, food consumption, alkaline phosphatase (AP) activity, and serum protein electrophoresis. The 72 hour LD50 of CB in rainbow trout after acute intoxication was 1.8 ml/kg. The toxicant caused behavioral changes in the fish which were consistent with the known anesthetic properties of CB in mammals. Elevations in BSP retention and GPT activity, and histopathology indicated that CB was hepatotoxic in the fish. The LC50 of CB in trout exposed via the water for 96 hours was 4.7 ppm. Chronic exposure of trout to CB resulted in similar behavioral changes as seen in the acute study. Liver toxicity was evident from elevations in GPT activity and decreased A/G ratios of serum proteins after 15 days of exposure. BSP retention and AP activity appeared to be affected by the nutritional status of the trout as much as by the CB treatment. After 30 days of exposure to CB, trout appeared to have adapted to the toxic effects of CB. These results indicate that CB is toxic to rainbow trout after either acute intoxication or chronic exposure via the water. Behavioral and soft organ toxicity of CB seen in this study may compromise the ability of the trout to thrive in its environment. Title: Acute and chronic toxicity studies with monochlorobenzene in rainbow trout Author: Dalich, George M. The toxicity of chlorobenzene (CB) was investigated in rainbow trout following acute ip administration (1. 0 ml/kg, 1:1 in corn oil) and chronic exposure (2. 1 ppm and 2. 9 ppm) via the water in a continuously flowing system for 15 and 30 days. In the acute study, overt toxicity and hepatotoxicity were monitored over a 96 hour time period. Variables measured to assess toxicity included LD50 determination, weight changes, liver weight to body weight ratios, behavioral changes, alanine aminotransferase activity (GPT), sulfobromophthalein (BSP) retention, total plasma protein concentration and liver histopathology. In the chronic study the same measures of toxicity were followed as well as respiratory rates, oxygen consumption, food consumption, alkaline phosphatase (AP) activity, and serum protein electrophoresis. The 72 hour LD50 of CB in rainbow trout after acute intoxication was 1.8 ml/kg. The toxicant caused behavioral changes in the fish which were consistent with the known anesthetic properties of CB in mammals. Elevations in BSP retention and GPT activity, and histopathology indicated that CB was hepatotoxic in the fish. The LC50 of CB in trout exposed via the water for 96 hours was 4.7 ppm. Chronic exposure of trout to CB resulted in similar behavioral changes as seen in the acute study. Liver toxicity was evident from elevations in GPT activity and decreased A/G ratios of serum proteins after 15 days of exposure. BSP retention and AP activity appeared to be affected by the nutritional status of the trout as much as by the CB treatment. After 30 days of exposure to CB, trout appeared to have adapted to the toxic effects of CB. These results indicate that CB is toxic to rainbow trout after either acute intoxication or chronic exposure via the water. Behavioral and soft organ toxicity of CB seen in this study may compromise the ability of the trout to thrive in its environment. Close

• 86. [Article] Net production, movement, and food of cutthroat trout (Salmo clarki clarki Richardson) in three Oregon coastal streams

  Unfished populations of cutthroat trout in three small coastal streams in Oregon were studied from April of 1962 until November of 1963. Population size, growth rate, and net production were estimated ...

  Citation × Citation Citation Abstract Copy Title: Net production, movement, and food of cutthroat trout (Salmo clarki clarki Richardson) in three Oregon coastal streams Author: Lowry, Gerald Roger Unfished populations of cutthroat trout in three small coastal streams in Oregon were studied from April of 1962 until November of 1963. Population size, growth rate, and net production were estimated for study areas in each stream. The nature of seasonal movement patterns within the study areas and at fish traps was examined. Food habits of trout during the time of emergence and early growth of coho fry were studied. The mean annual biomass of cutthroat trout for all streams was 4.2 grams per square meter. Growth in length was greatest in April and May and least in October and November. Net production averaged 4.1 grams per square meter for the three streams. Growth rates were about equal in the three streams, but production levels were about 20 percent higher in one stream. Upstream migrations of trout occurred from late October until March, with a maximum in December. Kelts returned downstream from December to April with the greatest numbers in January and February. More than 90 percent of the downstream movement of smolts occurred in February, March, April and May, with numbers being consistently greatest in April. Two-year-old smolts dominated the run in the two larger streams, while one-year-old smolts did so in the smallest stream. Small tributaries of the study areas were found to be very important to cutthroat trout reproduction. Young trout were noted to leave the tributaries at about one year of age. Trout 150 mm in length that had never left the study streams were found in a gravid condition near redd sites. Food samples taken during the period of coho fry emergence and early growth failed to show that cutthroat trout were important consumers of young coho. Aquatic arthropods were consistently an important part of the diet; earthworms decreased in importance; and terrestrial arthropods increased in importance during the period from February to June. Title: Net production, movement, and food of cutthroat trout (Salmo clarki clarki Richardson) in three Oregon coastal streams Author: Lowry, Gerald Roger Unfished populations of cutthroat trout in three small coastal streams in Oregon were studied from April of 1962 until November of 1963. Population size, growth rate, and net production were estimated for study areas in each stream. The nature of seasonal movement patterns within the study areas and at fish traps was examined. Food habits of trout during the time of emergence and early growth of coho fry were studied. The mean annual biomass of cutthroat trout for all streams was 4.2 grams per square meter. Growth in length was greatest in April and May and least in October and November. Net production averaged 4.1 grams per square meter for the three streams. Growth rates were about equal in the three streams, but production levels were about 20 percent higher in one stream. Upstream migrations of trout occurred from late October until March, with a maximum in December. Kelts returned downstream from December to April with the greatest numbers in January and February. More than 90 percent of the downstream movement of smolts occurred in February, March, April and May, with numbers being consistently greatest in April. Two-year-old smolts dominated the run in the two larger streams, while one-year-old smolts did so in the smallest stream. Small tributaries of the study areas were found to be very important to cutthroat trout reproduction. Young trout were noted to leave the tributaries at about one year of age. Trout 150 mm in length that had never left the study streams were found in a gravid condition near redd sites. Food samples taken during the period of coho fry emergence and early growth failed to show that cutthroat trout were important consumers of young coho. Aquatic arthropods were consistently an important part of the diet; earthworms decreased in importance; and terrestrial arthropods increased in importance during the period from February to June. Close

• 87. [Image] The trout and salmon of the Pacific coast

  	This article is an overview of the variety of trout and salmon that are found in Oregon and Washington states.
  	Citation × Citation Citation Abstract Copy Title: The trout and salmon of the Pacific coast Author: Jordan, David Starr Year: 1906, 2005, 2004 This article is an overview of the variety of trout and salmon that are found in Oregon and Washington states. Title: The trout and salmon of the Pacific coast Author: Jordan, David Starr Year: 1906, 2005, 2004 This article is an overview of the variety of trout and salmon that are found in Oregon and Washington states. Close

• 88. [Article] 2012 Trapper Creek Redd surveys

  Abstract -- Odell Lake was once directly connected to the upper Deschutes River basin, but recent geologic activity severed this connection with the creation of Davis Lake. Despite a lack of connection ...

  Citation × Citation Citation Abstract Copy Title: 2012 Trapper Creek Redd surveys Abstract -- Odell Lake was once directly connected to the upper Deschutes River basin, but recent geologic activity severed this connection with the creation of Davis Lake. Despite a lack of connection to the Deschutes River, indigenous bull trout (Salvelinus confluentus) subsist in Odell Lake. The Odell Lake bull trout are now the only natural adfluvial bull trout population in Oregon. Despite their persistence; angling mortality, habitat degradation, hybridization, and competition with introduced species limit bull trout populations. Bull trout were listed as threatened under the Endangered Species Act in 1998 (Office of the Federal Register 63 [June 10, 1998]: 31647). ODFW has monitored this population closely by conducting weekly redd counts on an annual basis and mapping redd locations to identify areas of optimal spawning habitat in Trapper Creek. Title: 2012 Trapper Creek Redd surveys Abstract -- Odell Lake was once directly connected to the upper Deschutes River basin, but recent geologic activity severed this connection with the creation of Davis Lake. Despite a lack of connection to the Deschutes River, indigenous bull trout (Salvelinus confluentus) subsist in Odell Lake. The Odell Lake bull trout are now the only natural adfluvial bull trout population in Oregon. Despite their persistence; angling mortality, habitat degradation, hybridization, and competition with introduced species limit bull trout populations. Bull trout were listed as threatened under the Endangered Species Act in 1998 (Office of the Federal Register 63 [June 10, 1998]: 31647). ODFW has monitored this population closely by conducting weekly redd counts on an annual basis and mapping redd locations to identify areas of optimal spawning habitat in Trapper Creek. Close

• 89. [Article] Diamond Lake Fish Management Issues

  This document covers the massive decline in catch and return on trout stocked in Diamond Lake starting in the 90s and describes issues addressing the most likely cause, an increased Tui chub population ...

  Citation × Citation Citation Abstract Copy Title: Diamond Lake Fish Management Issues Author: Oregon. Department of Fish and Wildlife This document covers the massive decline in catch and return on trout stocked in Diamond Lake starting in the 90s and describes issues addressing the most likely cause, an increased Tui chub population competing for resources with the trout. The report discusses the persistent issue of Tui chub in Diamond Lake, and compares catch of Tui chub and Rainbow trout from Diamond Lake from 1985 through 1995. See also: A preliminary report on the Diamond Lake study, which discusses a similar issue in 1947. https://ir.library.oregonstate.edu/xmlui/handle/1957/42827 Title: Diamond Lake Fish Management Issues Author: Oregon. Department of Fish and Wildlife This document covers the massive decline in catch and return on trout stocked in Diamond Lake starting in the 90s and describes issues addressing the most likely cause, an increased Tui chub population competing for resources with the trout. The report discusses the persistent issue of Tui chub in Diamond Lake, and compares catch of Tui chub and Rainbow trout from Diamond Lake from 1985 through 1995. See also: A preliminary report on the Diamond Lake study, which discusses a similar issue in 1947. https://ir.library.oregonstate.edu/xmlui/handle/1957/42827 Close

• 90. [Article] A summary of coastal cutthroat trout studies, 1962-1965

  This report summarizes research on coastal cutthroat trout from the beginning of more intensive studies in 1962 through 1965. This report includes data on migration, survival/mortality, growth, and food ...

  Citation × Citation Citation Abstract Copy Title: A summary of coastal cutthroat trout studies, 1962-1965 Author: Bulkley, Ross V., Hansen, David, Skeesick, Del, Oregon. State Game Commission. Research Division This report summarizes research on coastal cutthroat trout from the beginning of more intensive studies in 1962 through 1965. This report includes data on migration, survival/mortality, growth, and food habits collected during this period. It also discusses the Siuslaw Estuary catch estimates. Title: A summary of coastal cutthroat trout studies, 1962-1965 Author: Bulkley, Ross V., Hansen, David, Skeesick, Del, Oregon. State Game Commission. Research Division This report summarizes research on coastal cutthroat trout from the beginning of more intensive studies in 1962 through 1965. This report includes data on migration, survival/mortality, growth, and food habits collected during this period. It also discusses the Siuslaw Estuary catch estimates. Close

• 91. [Article] Native Trout Studies, Annual Progress Report, Project # F-136-R-13

  Abstract -- We developed a proposal for studies to better describe 1) the seasonal movements and locations of adult westslope cutthroat trout in the mainstem John Day River subbasin, and 2) the characteristics ...

  Citation × Citation Citation Abstract Copy Title: Native Trout Studies, Annual Progress Report, Project # F-136-R-13 Abstract -- We developed a proposal for studies to better describe 1) the seasonal movements and locations of adult westslope cutthroat trout in the mainstem John Day River subbasin, and 2) the characteristics of habitats associated with these locations. We radio-tagged a total of 41 adult cutthroat trout, including six from Deardorff Creek, 18 from Roberts Creek, and 17 from Rail Creek to initiate efforts to describe their seasonal movements. We began to measure the characteristics of habitats used by these fish. In August, we helped survey Vinegar Creek (Middle Fork John Day River subbasin) for the presence of bull trout. Vinegar Creek was thought to no longer support bull trout, but these surveys led to the discovery of one. Title: Native Trout Studies, Annual Progress Report, Project # F-136-R-13 Abstract -- We developed a proposal for studies to better describe 1) the seasonal movements and locations of adult westslope cutthroat trout in the mainstem John Day River subbasin, and 2) the characteristics of habitats associated with these locations. We radio-tagged a total of 41 adult cutthroat trout, including six from Deardorff Creek, 18 from Roberts Creek, and 17 from Rail Creek to initiate efforts to describe their seasonal movements. We began to measure the characteristics of habitats used by these fish. In August, we helped survey Vinegar Creek (Middle Fork John Day River subbasin) for the presence of bull trout. Vinegar Creek was thought to no longer support bull trout, but these surveys led to the discovery of one. Close

• 92. [Article] Crooked River Fish Management Plan 1979

  Abstract -- The Crooked River is a major tributary to the Deschutes River and has the habitat to produce a good rainbow trout population, especially between Prineville Dam and Rice-Baldwin Dam. However, ...

  Citation × Citation Citation Abstract Copy Title: Crooked River Fish Management Plan 1979 Abstract -- The Crooked River is a major tributary to the Deschutes River and has the habitat to produce a good rainbow trout population, especially between Prineville Dam and Rice-Baldwin Dam. However, winter streamflow is minimal and high turbidity is common. The. river is not stocked but various ages and sizes of hatchery fish emigrate from Prineville Reservoir during periods of spill; and these fish constitute a sizable portion of the trout population in the river. The Crooked River has maintained a successful fishery on the combination of wild and hatchery (from Prinevi11e Reservoir) trout under general statewide regulations. In July 1979, the Oregon Fish and Wildlife Commission accepted the Department's recommendation to continue to manage this portion of Crooked River for wild and hatchery fish. Hatchery fish will not be stocked in this section of the river, but large numbers of hatchery trout migrate from Prineville Reservoir into the river below the dam. Title: Crooked River Fish Management Plan 1979 Abstract -- The Crooked River is a major tributary to the Deschutes River and has the habitat to produce a good rainbow trout population, especially between Prineville Dam and Rice-Baldwin Dam. However, winter streamflow is minimal and high turbidity is common. The. river is not stocked but various ages and sizes of hatchery fish emigrate from Prineville Reservoir during periods of spill; and these fish constitute a sizable portion of the trout population in the river. The Crooked River has maintained a successful fishery on the combination of wild and hatchery (from Prinevi11e Reservoir) trout under general statewide regulations. In July 1979, the Oregon Fish and Wildlife Commission accepted the Department's recommendation to continue to manage this portion of Crooked River for wild and hatchery fish. Hatchery fish will not be stocked in this section of the river, but large numbers of hatchery trout migrate from Prineville Reservoir into the river below the dam. Close

• 93. [Image] Upper Klamath Basin bull trout conservation strategy : part 1, a conceptual framework for recovery, final

  	EXECUTIVE SUMMARY This document presents the framework of a plan to reverse the decline of bull trout (Salvelinus confluentus) populations in the Klamath Basin. If successful, we expect bull trout ...
  	Citation × Citation Citation Abstract Copy Title: Upper Klamath Basin bull trout conservation strategy : part 1, a conceptual framework for recovery, final Author: Light, Jeffrey Year: 1996, 2008, 2005 EXECUTIVE SUMMARY This document presents the framework of a plan to reverse the decline of bull trout (Salvelinus confluentus) populations in the Klamath Basin. If successful, we expect bull trout to recover to a level where they will have a reasonable chance of long-term viability. The work is the collective effort of fish biologists, foresters, other natural resource management professionals, and local landowners representing a diverse array of interests and organizations. Together, these individuals have worked for several years to gather information pertaining to the distribution and status of Klamath bull trout populations and threats to their persistence. The members of the Bull Trout Working Group share the common desire to restore bull trout populations while at the same time sustaining their respective land use interests in the Klamath Basin. This approach provides incentives to all the interested parties to seek agreement on solutions, encouraging cooperative work on an otherwise ambitious and daunting task. The following few pages summarize the plan. Each area is covered again in greater detail in the body of the document. The goals established by the Bull Trout Working Group for this recovery plan are to (1) Secure existing bull trout populations, and (2) Expand the populations to some of their former range and numbers. We pursue these goals with a three step approach of assessment, implementation, and evaluation. We begin with a review of the distribution and status of bull trout generally, then specifically within the Klamath Basin. Next we present available data and interpretations supporting our conclusions regarding the type, magnitude, and extent of physical and biological factors or concerns that may hamper bull trout persistence. Land and fish management activities that contribute to these problem situations are then identified. This is followed by a blueprint for stepwise development and implementation of practical solutions. Finally, a monitoring plan is proposed to measure the success of the recovery efforts. The Klamath Basin Bull trout populations represent a valuable biological resource. These populations exist at the southern edge of the species' distribution, and have distinctive genetic character. In the Upper Klamath River Basin, bull trout are presently found as resident forms in eight isolated headwater streams within six small drainages. (4Headwater streams' in this document refers to very small streams, rather than rivers which are the headwaters for larger rivers). These streams occur in three general locations: they are tributaries of the Sprague River, of the Sycan River and of Upper Klamath Lake. Together, the known populations occupy approximately 23 miles (37 km) of perennial streams. Formerly, bull trout may have occurred in the mainstems of these systems (Gilbert 1897. Dambacher et al. 1992, Roger Smith, ODFW, pers. coram. 1994). In addition to existing populations, other populations are known to have recently occupied nearby streams (Cherry and Coyote creeks, the Upper Sycan River). Estimated current population sizes in each drainage range between 133 and 1,293, indicating that populations are low enough to warrant concern. These population sizes are smaller than the minimum viable population sizes predicted by conservation biology theory. A substantial risk of extirpation via natural disturbance cycles and stochastic events exists for such small populations. Streams that are presently inhabited by bull trout are typically small and spring-fed with steep gradients. They originate in the higher elevations of mountains within the Upper Klamath Basin and flow through forests where land uses range from wilderness and national parkland to commercial forestry and grazing. Eventually, these tributaries or their mainstem receiving waters leave the forest and flow through broad sagebrush-covered valleys or marshes where they widen and flatten. Here livestock grazing and agriculture are the dominant land uses. An assessment of the current situation regarding Klamath Basin bull trout was performed using existing and new information on life history, distribution, habitat requirements by lifestage, environmental requirements, exotic species interactions, angling pressure, land use interactions, habitat fragmentation, population fragmentation and many other factors. Basin-specific information on each of these factors was collected and analyzed, complemented by a thorough review of the literature. Past, present and possible future distributions of bull trout were examined. Particular emphasis was placed on determining the nature and extent of biotic interactions, because this potential agent of bull trout decline has not been thoroughly addressed in other works. Analysis of the assembled information resulted in the identification of several specific natural and anthropogenic factors which are thought to limit the distribution and persistence of bull trout. Habitat quality and quantity are affected by land use to some degree in all currently inhabited bull trout streams except upper Sun Creek. Generally, habitat conditions vary from fair to good in existing bull trout streams. We identified several land uses that have reduced habitat quality. Principal among the abiotic factors of concern is fine sediment loading from (1) road erosion, (2) stream bank and adjacent ground disturbance by livestock, and (3) Bull Trout Document - Final - - 6 - 26-Jan-96 stream-adjacent hillslope erosion from logging. Second among the abiotic factors of concern is elevated temperature. Other concerns include diminished large woody debris (LWD) recruitment, declining bank integrity, low flows, changes in stream morphology, and blocked or hindered fish passage. The relative importance of each of these factors or concerns differs by watershed, or by location within a watershed. In most cases, information on specific issues and their locations is available with sufficient resolution to allow land managers to develop action plans to address them. Possible exceptions may include Deming Creek, where Watershed Analysis has not yet been performed. Based on the assessment results to date, the following strategy was developed to address limiting factors and concerns. Competitive and genetic interactions with non-native brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) were found to be important biotic factors currently threatening the persistence of bull trout in the Klamath Basin. This conclusion was based on the almost pervasive presence of these exotic competitors and the significance of their negative interactions as determined from the literature and from local observations in headwater streams. Temperature may be a significant issue, especially for juvenile rearing, although the temperature tolerances of bull trout are not well understood. Habitat fragmentation and alteration appear to have been major issues in the past, resulting in population fragmentation, particularly at lower elevations and in larger streams where bull trout may have ranged historically. These final two factors appear less important than exotic competitors or temperature for bull trout in the current limited ranges in headwater streams, though they are important in mainstems and larger tributaries. They will need to be addressed if large scale restoration is undertaken. With the exceptions of temperature and fine sediment, brook trout have habitat requirements and environmental tolerances similar to bull trout, and they thrive in many Klamath Basin headwater streams while bull trout do not. Brown trout pose a competitive threat similar to that posed by brook trout, but the mechanisms of displacement and the areas where they occur differ. Even in environments unaltered by land management, such as Sun Creek within Crater Lake National Park, exotic trout are displacing bull trout. This conclusion is consistent with findings throughout the west, where competition with exotic species has clearly had a major effect on bull trout range, resulting in widespread declines in bull trout distribution. Changes in habitat may have altered competitive interactions between bull trout and other salmonids, both directly and indirectly. Since changes in environmental factors can exacerbate competition issues in sensitive populations, habitat condition remains a concern. Near-term, mid-term, and long-term strategy for Recovery of Bull Trout Populations Our approach to recovery of the Klamath basin's bull trout populations is a two-phase effort corresponding to near- and mid-term objectives, and an examination of possible long-term recovery objectives. It entails securing and maintaining existing populations followed by expansion into former headwater and downstream habitats, and ultimately the possibility of connecting tributaries with mainstem linkages. Assessment, research and monitoring needs associated with each phase were identified (see main body of text). Specific project details such as funding, work schedules, participant responsibilities, specific actions, implementation methods and costs are not presented but are to be developed collectively by the Bull Trout Working Group. Phase 1: Securing existing populations This phase of the recovery plan focuses on the six small drainages where bull trout populations are known to exist today. Here we wish to prevent further decline of individual populations as a step toward securing the viability of the Klamath Basin metapopulation(s).1 This is accomplished by addressing biotic and abiotic factors that threaten the persistence of these populations. The most immediate threat is the continued presence of non-native salmonids. Localized areas of habitat degradation or alteration from sediment inputs and shade removal are an additional serious concern. It may be feasible to isolate bull trout populations above barriers, followed by eradication of brook and brown trout within each isolated stream reach. This approach will be tested early in Phase 7, with particular attention to unforeseen consequences on the ecology of the test streams. Assuming it is viable, this approach will become the focus of Phases 1 & 2, in parallel with habitat enhancement efforts. Habitat enhancement is generally feasible, particularly in areas where roads or livestock are the issues. Where needed, such habitat enhancement efforts are expected to be completed as part of Phases 1&2. It will be necessary to understand the distribution of genetic variation among existing sub-populations of bull trout in order to embark on a well 1 For an understanding of metapopulation considerations, see the body of the text, in particular the section on 'Metapopulations and sub-populations' on page 60. Bull Trout Document - Final - - 7 - 26-Jan-96 directed range expansion program. Baseline data would be essential for genetic monitoring activities and for the development of stocks for establishing new sub-populations in subsequent phases. If successful, the actions taken in Phase 1 are expected to eliminate the direct threats to existing bull trout sub-populations posed by non-native salmonids. Parallel efforts to improve the in-stream physical environment to ensure habitat is suitable for bull trout are expected to eliminate proximate environmental threats to existing bull trout sub-populations. This effort will require that abiotic limiting factors and concerns be addressed via land management activities, most of which fall within the realm of forest land management. Timber harvest and regeneration, roads (construction, use, and maintenance), and livestock grazing programs are considered. Immediate actions may take the form of road erosion abatement, including road abandonment and revegetation. Some of these actions can be accomplished when a particular unit is harvested, while others may be pursued as independent restoration activities (e.g., livestock management plans, culvert replacements). Presently, no in-stream fish habitat improvement projects have been proposed, and none are foreseen for stream reaches affected by this phase of the recovery plan. Most of the concerns related to livestock are focused within the riparian zone. Some riparian locations are much more sensitive than others, for example the large meadow in Long Creek. Actions to address these concerns will vary by landowner and location, and may range from complete riparian exclosure to short-term grazing to continuous but moderate access. The preferred actions will depend on the success of these various strategies in bringing about the desired response of the channel and fish habitat, and can be expected to change as recovery of riparian areas progresses. Effectiveness monitoring will be invaluable for measuring the success of these efforts, and in adapting our management strategy during the implementation. No water diversion concerns have been identified for this phase of the plan, except for Deming Creek, where screening of irrigation ditches may be warranted. Some additional fish management actions may also be applicable in Phase 7, for example to continue to monitor compliance with existing no kill regulations in bull trout streams. Other pertinent fish management issues have been addressed already, for example the cessation of exotic trout stocking (brook, brown or non-native rainbow) in bull trout streams. Phase 2: Expanding the range of bull trout within headwater streams In Phase 2, bull trout populations are refounded in headwater streams which now support brook trout, e.g. Calahan and Cherry creeks, or possibly in creeks without fish, e.g. Sheep Creek on the North Fork Sprague. This serves to expand the number of sub-populations, increases the number of refugia, and increases the overall size of the Klamath metapopulation(s). This is a major step in the establishment of viable metapopulations; by increasing the number of sub-populations, the effect of the loss or decline of any particular sub-population is reduced, making the metapopulation(s) more resilient to natural disturbance, variations in breeding success, disease outbreaks and other stochastic factors. Phase 2 consists of two parts: Phase 2a, in which sub-populations are founded in streams which only recently lost bull trout (e.g. Cherry Creek, Coyote Creek and the upper Sycan River) and Phase 2b, in which sub-populations are founded in other suitable headwater habitat, as indicated by the presence of thriving brook trout sub-populations (e.g. Sevenmile Creek, Calahan Creek, Annie Creek, Camp Creek, Jackson Creek, Deep Creek and Corral Creek). Both parts of Phase 2 are accomplished in much the same way as Phase 7: Barriers are constructed to exclude brook trout and brown trout, then the exotic species are eradicated above the barriers. Bull trout populations are then founded with human-introduced bull trout, whether via transplantation from wild sources or from a hatchery. Care must be exercised to maintain adequate genetic diversity in the founded sub-populations as establishment of genetically healthy populations is a non-trivial task. An inherent risk in newly created sub-populations is the loss of genetic variation (founder effect), which if great enough can reduce the vigor of the population and its long-term viability. As in Phase 7, stresses from abiotic factors, such as excessive delivery of fine sediment, low flows, or warm water temperatures, need to be reduced in parallel with the removal of exotics. Streamside roads, road crossings, low flows in upper reaches, and livestock are situations of concern in many of the streams, and warm temperatures are in some. Also as in phase 7, monitoring for the presence of exotics, bull trout population parameters, and abiotic factors is an important follow-up activity to track and ensure long-term success. In addition, genetic monitoring of newly founded populations is indicated. Bull Trout Document - Final - -8- 26-Jan-96 A possible future direction after Phase 2 Once Phase 2 is complete, the Bull Trout Working Group will pause to assess the efforts completed and plan future efforts. If phases 1 and 2 are successful, there will be significant numbers of bull trout in various tributaries, but possibly little genetic exchange between them. Bull trout range may still be restricted to headwater streams. During the evaluation and reassessment of the recovery effort, the group will re-consider the long-term recovery objectives. Based on what we know now, two possible recovery objectives are likely to be considered. The first such possible objective is the establishment of natural movement corridors between adjacent headwater streams, thereby establishing complete and viable metapopulation(s) of bull trout within the Upper Klamath Basin. Connectivity between headwater streams would allow volitional movement of bull trout. Movement would allow dispersal, founding of new sub-populations, and interbreeding between sub-populations, within the local sub-basin. Establishing natural movement corridors between headwater streams may require that selected reaches of larger tributaries or even portions of mainstem rivers be restored to suitable habitat for bull trout. This would be an ambitious undertaking, which may be infeasible. It might require the elimination or exclusion of exotics, the removal of man-made barriers which prevent movement between streams, or alterations in current land use to reduce anthropogenically induced fine sediment loads, low flows, warm stream temperatures, or changes in channel morphology. The change in focus from headwater streams to larger tributaries represents an escalation in the scale and complexity of the restoration effort. Exclusion of exotics is much more difficult. Land use effects, whether from water diversions or livestock grazing are often more significant. The second possible objective of future efforts after Phase 2 is to attemp to re-establish fluvial populations of bull trout in selected mainstem rivers of the Upper Klamath Basin, in such a way as to connect the sub-populations of each metapopulation. Fluvial bull trout are far larger than stream resident bull trout, and have much higher fecundity as a result. This gives them a tremendous advantage in breeding, whether in founding new sub-populations, or augmenting existing sub-populations. By establishing a fluvial form of bull trout in the Upper Klamath Basin, overall viability of the metapopulation(s) should be greatly increased. Timeline for implementation A prototype Phase 1 implementation is likely to be completed within 2-5 years. Full implementation of Phase 1 may take many years, but the bulk of the work could be completed in 10-20 years. Further assessment work and some aspects of Phase 2 will be accomplished concurrent with Phase 1 efforts over the next several years, but may require 5-10 years before being well underway. Specific timelines for individual projects in phases 1 and 2 and the overall recovery effort will be developed by the Bull Trout Working Group. Summary and prognosis for bull trout populations in the Upper Klamath River Basin If our analysis is accurate, the Klamath Basin's native bull trout populations are imperiled, yet their future need not be bleak. They persist today as a handful of isolated sub-populations in small, headwater streams. If a fluvial life history form existed, as it may have at one time in the Wood River2, no longer occurs or is a very small (i.e., undetectable) component of the current Klamath River Basin population. Gene flow between these sub-populations has apparently ceased. Individual population sizes are small enough to be near or below minimum viable levels as defined by current theorists in conservation biology. Competition from introduced brook and brown trout is widespread, with severe long-term consequences. Habitat conditions vary from stream to stream, depending on the nature and extent of land uses around and downstream of the bull trout tributaries. Fine sediment inputs and elevated stream temperatures are the principal habitat issue. Water withdrawals, altered channels and flood plains, and other anthropogenic influences have contributed to loss of mainstem fluvial habitat, and may have ultimately resulted in habitat fragmentation, followed by isolation of the remaining populations. Together, these conditions do not bode well for the longevity of native bull trout populations. We believe concerted efforts to resolve the identified problems can achieve the goals of maintaining, and possibly restoring, Klamath bull trout populations. Further, we believe that without attention, one or more of the identified limiting factors will almost certainly spell an end to most or all of the sub-populations in the basin. 2 A 330 mm specimen was collected from Fort Creek, a tributary to the Wood River, in 1876. Cited in Cavendar 1978; Smithsonian Accession Number 16793. Bull Trout Document - Final - -9 - 26-Jan-96 Title: Upper Klamath Basin bull trout conservation strategy : part 1, a conceptual framework for recovery, final Author: Light, Jeffrey Year: 1996, 2008, 2005 EXECUTIVE SUMMARY This document presents the framework of a plan to reverse the decline of bull trout (Salvelinus confluentus) populations in the Klamath Basin. If successful, we expect bull trout to recover to a level where they will have a reasonable chance of long-term viability. The work is the collective effort of fish biologists, foresters, other natural resource management professionals, and local landowners representing a diverse array of interests and organizations. Together, these individuals have worked for several years to gather information pertaining to the distribution and status of Klamath bull trout populations and threats to their persistence. The members of the Bull Trout Working Group share the common desire to restore bull trout populations while at the same time sustaining their respective land use interests in the Klamath Basin. This approach provides incentives to all the interested parties to seek agreement on solutions, encouraging cooperative work on an otherwise ambitious and daunting task. The following few pages summarize the plan. Each area is covered again in greater detail in the body of the document. The goals established by the Bull Trout Working Group for this recovery plan are to (1) Secure existing bull trout populations, and (2) Expand the populations to some of their former range and numbers. We pursue these goals with a three step approach of assessment, implementation, and evaluation. We begin with a review of the distribution and status of bull trout generally, then specifically within the Klamath Basin. Next we present available data and interpretations supporting our conclusions regarding the type, magnitude, and extent of physical and biological factors or concerns that may hamper bull trout persistence. Land and fish management activities that contribute to these problem situations are then identified. This is followed by a blueprint for stepwise development and implementation of practical solutions. Finally, a monitoring plan is proposed to measure the success of the recovery efforts. The Klamath Basin Bull trout populations represent a valuable biological resource. These populations exist at the southern edge of the species' distribution, and have distinctive genetic character. In the Upper Klamath River Basin, bull trout are presently found as resident forms in eight isolated headwater streams within six small drainages. (4Headwater streams' in this document refers to very small streams, rather than rivers which are the headwaters for larger rivers). These streams occur in three general locations: they are tributaries of the Sprague River, of the Sycan River and of Upper Klamath Lake. Together, the known populations occupy approximately 23 miles (37 km) of perennial streams. Formerly, bull trout may have occurred in the mainstems of these systems (Gilbert 1897. Dambacher et al. 1992, Roger Smith, ODFW, pers. coram. 1994). In addition to existing populations, other populations are known to have recently occupied nearby streams (Cherry and Coyote creeks, the Upper Sycan River). Estimated current population sizes in each drainage range between 133 and 1,293, indicating that populations are low enough to warrant concern. These population sizes are smaller than the minimum viable population sizes predicted by conservation biology theory. A substantial risk of extirpation via natural disturbance cycles and stochastic events exists for such small populations. Streams that are presently inhabited by bull trout are typically small and spring-fed with steep gradients. They originate in the higher elevations of mountains within the Upper Klamath Basin and flow through forests where land uses range from wilderness and national parkland to commercial forestry and grazing. Eventually, these tributaries or their mainstem receiving waters leave the forest and flow through broad sagebrush-covered valleys or marshes where they widen and flatten. Here livestock grazing and agriculture are the dominant land uses. An assessment of the current situation regarding Klamath Basin bull trout was performed using existing and new information on life history, distribution, habitat requirements by lifestage, environmental requirements, exotic species interactions, angling pressure, land use interactions, habitat fragmentation, population fragmentation and many other factors. Basin-specific information on each of these factors was collected and analyzed, complemented by a thorough review of the literature. Past, present and possible future distributions of bull trout were examined. Particular emphasis was placed on determining the nature and extent of biotic interactions, because this potential agent of bull trout decline has not been thoroughly addressed in other works. Analysis of the assembled information resulted in the identification of several specific natural and anthropogenic factors which are thought to limit the distribution and persistence of bull trout. Habitat quality and quantity are affected by land use to some degree in all currently inhabited bull trout streams except upper Sun Creek. Generally, habitat conditions vary from fair to good in existing bull trout streams. We identified several land uses that have reduced habitat quality. Principal among the abiotic factors of concern is fine sediment loading from (1) road erosion, (2) stream bank and adjacent ground disturbance by livestock, and (3) Bull Trout Document - Final - - 6 - 26-Jan-96 stream-adjacent hillslope erosion from logging. Second among the abiotic factors of concern is elevated temperature. Other concerns include diminished large woody debris (LWD) recruitment, declining bank integrity, low flows, changes in stream morphology, and blocked or hindered fish passage. The relative importance of each of these factors or concerns differs by watershed, or by location within a watershed. In most cases, information on specific issues and their locations is available with sufficient resolution to allow land managers to develop action plans to address them. Possible exceptions may include Deming Creek, where Watershed Analysis has not yet been performed. Based on the assessment results to date, the following strategy was developed to address limiting factors and concerns. Competitive and genetic interactions with non-native brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) were found to be important biotic factors currently threatening the persistence of bull trout in the Klamath Basin. This conclusion was based on the almost pervasive presence of these exotic competitors and the significance of their negative interactions as determined from the literature and from local observations in headwater streams. Temperature may be a significant issue, especially for juvenile rearing, although the temperature tolerances of bull trout are not well understood. Habitat fragmentation and alteration appear to have been major issues in the past, resulting in population fragmentation, particularly at lower elevations and in larger streams where bull trout may have ranged historically. These final two factors appear less important than exotic competitors or temperature for bull trout in the current limited ranges in headwater streams, though they are important in mainstems and larger tributaries. They will need to be addressed if large scale restoration is undertaken. With the exceptions of temperature and fine sediment, brook trout have habitat requirements and environmental tolerances similar to bull trout, and they thrive in many Klamath Basin headwater streams while bull trout do not. Brown trout pose a competitive threat similar to that posed by brook trout, but the mechanisms of displacement and the areas where they occur differ. Even in environments unaltered by land management, such as Sun Creek within Crater Lake National Park, exotic trout are displacing bull trout. This conclusion is consistent with findings throughout the west, where competition with exotic species has clearly had a major effect on bull trout range, resulting in widespread declines in bull trout distribution. Changes in habitat may have altered competitive interactions between bull trout and other salmonids, both directly and indirectly. Since changes in environmental factors can exacerbate competition issues in sensitive populations, habitat condition remains a concern. Near-term, mid-term, and long-term strategy for Recovery of Bull Trout Populations Our approach to recovery of the Klamath basin's bull trout populations is a two-phase effort corresponding to near- and mid-term objectives, and an examination of possible long-term recovery objectives. It entails securing and maintaining existing populations followed by expansion into former headwater and downstream habitats, and ultimately the possibility of connecting tributaries with mainstem linkages. Assessment, research and monitoring needs associated with each phase were identified (see main body of text). Specific project details such as funding, work schedules, participant responsibilities, specific actions, implementation methods and costs are not presented but are to be developed collectively by the Bull Trout Working Group. Phase 1: Securing existing populations This phase of the recovery plan focuses on the six small drainages where bull trout populations are known to exist today. Here we wish to prevent further decline of individual populations as a step toward securing the viability of the Klamath Basin metapopulation(s).1 This is accomplished by addressing biotic and abiotic factors that threaten the persistence of these populations. The most immediate threat is the continued presence of non-native salmonids. Localized areas of habitat degradation or alteration from sediment inputs and shade removal are an additional serious concern. It may be feasible to isolate bull trout populations above barriers, followed by eradication of brook and brown trout within each isolated stream reach. This approach will be tested early in Phase 7, with particular attention to unforeseen consequences on the ecology of the test streams. Assuming it is viable, this approach will become the focus of Phases 1 & 2, in parallel with habitat enhancement efforts. Habitat enhancement is generally feasible, particularly in areas where roads or livestock are the issues. Where needed, such habitat enhancement efforts are expected to be completed as part of Phases 1&2. It will be necessary to understand the distribution of genetic variation among existing sub-populations of bull trout in order to embark on a well 1 For an understanding of metapopulation considerations, see the body of the text, in particular the section on 'Metapopulations and sub-populations' on page 60. Bull Trout Document - Final - - 7 - 26-Jan-96 directed range expansion program. Baseline data would be essential for genetic monitoring activities and for the development of stocks for establishing new sub-populations in subsequent phases. If successful, the actions taken in Phase 1 are expected to eliminate the direct threats to existing bull trout sub-populations posed by non-native salmonids. Parallel efforts to improve the in-stream physical environment to ensure habitat is suitable for bull trout are expected to eliminate proximate environmental threats to existing bull trout sub-populations. This effort will require that abiotic limiting factors and concerns be addressed via land management activities, most of which fall within the realm of forest land management. Timber harvest and regeneration, roads (construction, use, and maintenance), and livestock grazing programs are considered. Immediate actions may take the form of road erosion abatement, including road abandonment and revegetation. Some of these actions can be accomplished when a particular unit is harvested, while others may be pursued as independent restoration activities (e.g., livestock management plans, culvert replacements). Presently, no in-stream fish habitat improvement projects have been proposed, and none are foreseen for stream reaches affected by this phase of the recovery plan. Most of the concerns related to livestock are focused within the riparian zone. Some riparian locations are much more sensitive than others, for example the large meadow in Long Creek. Actions to address these concerns will vary by landowner and location, and may range from complete riparian exclosure to short-term grazing to continuous but moderate access. The preferred actions will depend on the success of these various strategies in bringing about the desired response of the channel and fish habitat, and can be expected to change as recovery of riparian areas progresses. Effectiveness monitoring will be invaluable for measuring the success of these efforts, and in adapting our management strategy during the implementation. No water diversion concerns have been identified for this phase of the plan, except for Deming Creek, where screening of irrigation ditches may be warranted. Some additional fish management actions may also be applicable in Phase 7, for example to continue to monitor compliance with existing no kill regulations in bull trout streams. Other pertinent fish management issues have been addressed already, for example the cessation of exotic trout stocking (brook, brown or non-native rainbow) in bull trout streams. Phase 2: Expanding the range of bull trout within headwater streams In Phase 2, bull trout populations are refounded in headwater streams which now support brook trout, e.g. Calahan and Cherry creeks, or possibly in creeks without fish, e.g. Sheep Creek on the North Fork Sprague. This serves to expand the number of sub-populations, increases the number of refugia, and increases the overall size of the Klamath metapopulation(s). This is a major step in the establishment of viable metapopulations; by increasing the number of sub-populations, the effect of the loss or decline of any particular sub-population is reduced, making the metapopulation(s) more resilient to natural disturbance, variations in breeding success, disease outbreaks and other stochastic factors. Phase 2 consists of two parts: Phase 2a, in which sub-populations are founded in streams which only recently lost bull trout (e.g. Cherry Creek, Coyote Creek and the upper Sycan River) and Phase 2b, in which sub-populations are founded in other suitable headwater habitat, as indicated by the presence of thriving brook trout sub-populations (e.g. Sevenmile Creek, Calahan Creek, Annie Creek, Camp Creek, Jackson Creek, Deep Creek and Corral Creek). Both parts of Phase 2 are accomplished in much the same way as Phase 7: Barriers are constructed to exclude brook trout and brown trout, then the exotic species are eradicated above the barriers. Bull trout populations are then founded with human-introduced bull trout, whether via transplantation from wild sources or from a hatchery. Care must be exercised to maintain adequate genetic diversity in the founded sub-populations as establishment of genetically healthy populations is a non-trivial task. An inherent risk in newly created sub-populations is the loss of genetic variation (founder effect), which if great enough can reduce the vigor of the population and its long-term viability. As in Phase 7, stresses from abiotic factors, such as excessive delivery of fine sediment, low flows, or warm water temperatures, need to be reduced in parallel with the removal of exotics. Streamside roads, road crossings, low flows in upper reaches, and livestock are situations of concern in many of the streams, and warm temperatures are in some. Also as in phase 7, monitoring for the presence of exotics, bull trout population parameters, and abiotic factors is an important follow-up activity to track and ensure long-term success. In addition, genetic monitoring of newly founded populations is indicated. Bull Trout Document - Final - -8- 26-Jan-96 A possible future direction after Phase 2 Once Phase 2 is complete, the Bull Trout Working Group will pause to assess the efforts completed and plan future efforts. If phases 1 and 2 are successful, there will be significant numbers of bull trout in various tributaries, but possibly little genetic exchange between them. Bull trout range may still be restricted to headwater streams. During the evaluation and reassessment of the recovery effort, the group will re-consider the long-term recovery objectives. Based on what we know now, two possible recovery objectives are likely to be considered. The first such possible objective is the establishment of natural movement corridors between adjacent headwater streams, thereby establishing complete and viable metapopulation(s) of bull trout within the Upper Klamath Basin. Connectivity between headwater streams would allow volitional movement of bull trout. Movement would allow dispersal, founding of new sub-populations, and interbreeding between sub-populations, within the local sub-basin. Establishing natural movement corridors between headwater streams may require that selected reaches of larger tributaries or even portions of mainstem rivers be restored to suitable habitat for bull trout. This would be an ambitious undertaking, which may be infeasible. It might require the elimination or exclusion of exotics, the removal of man-made barriers which prevent movement between streams, or alterations in current land use to reduce anthropogenically induced fine sediment loads, low flows, warm stream temperatures, or changes in channel morphology. The change in focus from headwater streams to larger tributaries represents an escalation in the scale and complexity of the restoration effort. Exclusion of exotics is much more difficult. Land use effects, whether from water diversions or livestock grazing are often more significant. The second possible objective of future efforts after Phase 2 is to attemp to re-establish fluvial populations of bull trout in selected mainstem rivers of the Upper Klamath Basin, in such a way as to connect the sub-populations of each metapopulation. Fluvial bull trout are far larger than stream resident bull trout, and have much higher fecundity as a result. This gives them a tremendous advantage in breeding, whether in founding new sub-populations, or augmenting existing sub-populations. By establishing a fluvial form of bull trout in the Upper Klamath Basin, overall viability of the metapopulation(s) should be greatly increased. Timeline for implementation A prototype Phase 1 implementation is likely to be completed within 2-5 years. Full implementation of Phase 1 may take many years, but the bulk of the work could be completed in 10-20 years. Further assessment work and some aspects of Phase 2 will be accomplished concurrent with Phase 1 efforts over the next several years, but may require 5-10 years before being well underway. Specific timelines for individual projects in phases 1 and 2 and the overall recovery effort will be developed by the Bull Trout Working Group. Summary and prognosis for bull trout populations in the Upper Klamath River Basin If our analysis is accurate, the Klamath Basin's native bull trout populations are imperiled, yet their future need not be bleak. They persist today as a handful of isolated sub-populations in small, headwater streams. If a fluvial life history form existed, as it may have at one time in the Wood River2, no longer occurs or is a very small (i.e., undetectable) component of the current Klamath River Basin population. Gene flow between these sub-populations has apparently ceased. Individual population sizes are small enough to be near or below minimum viable levels as defined by current theorists in conservation biology. Competition from introduced brook and brown trout is widespread, with severe long-term consequences. Habitat conditions vary from stream to stream, depending on the nature and extent of land uses around and downstream of the bull trout tributaries. Fine sediment inputs and elevated stream temperatures are the principal habitat issue. Water withdrawals, altered channels and flood plains, and other anthropogenic influences have contributed to loss of mainstem fluvial habitat, and may have ultimately resulted in habitat fragmentation, followed by isolation of the remaining populations. Together, these conditions do not bode well for the longevity of native bull trout populations. We believe concerted efforts to resolve the identified problems can achieve the goals of maintaining, and possibly restoring, Klamath bull trout populations. Further, we believe that without attention, one or more of the identified limiting factors will almost certainly spell an end to most or all of the sub-populations in the basin. 2 A 330 mm specimen was collected from Fort Creek, a tributary to the Wood River, in 1876. Cited in Cavendar 1978; Smithsonian Accession Number 16793. Bull Trout Document - Final - -9 - 26-Jan-96 Close

• 94. [Article] Biology and production of the red-band trout (Salmo sp.) in four southeastern Oregon streams

  The red-band trout is native to many small, isolated streams in southeastern Oregon. A study of the red-band population of Three- mile Creek and Reservoir was conducted from August 1973 to June 1975. Data ...

  Citation × Citation Citation Abstract Copy Title: Biology and production of the red-band trout (Salmo sp.) in four southeastern Oregon streams Author: Kunkel, Clair The red-band trout is native to many small, isolated streams in southeastern Oregon. A study of the red-band population of Three- mile Creek and Reservoir was conducted from August 1973 to June 1975. Data were collected concerning population size, age composition, growth, biomass, recruitment, fecundity, and habitat. During the spring of 1975 similar data were collected for red-band populations in Home, Rattlesnake, and Buck creeks. The average trout biomass in Threemile Creek was 24.2 g/m2 and average production was 17.2 g/m2/yr. The production rate of 17.2 g/m2/yr is among the highest reported for salmonids in small streams and is probably in part due to the stable environment afforded by the springs which feed Threemile Creek. Biomass in the other study streams ranged from 2.4 to more than 6.7 g/m2 and production ranged from 1.2 to more than 4.2 g/m2/yr, not including production of age O-I fish. Trout biomass in Threemile Reservoir was 84 kg/ha in September 1974, and annual production was 80 kg/ha. The presence of the reservoir has increased the total production of the Threemile system by at least 12 times. Most female trout in the streams and reservoir matured at age III. Egg production in the Threemile system was considerably greater than in the other study streams. Spawners from the reservoir contributed nearly five times as many eggs to Threemile Creek as did the stream-dwelling females during the spring of 1974. The egg contribution of reservoir fish was probably greater than that required to perpetuate the observed trout densities in the stream. However, the resulting high density of fry may insure adequate contribution of young trout to the reservoir. Reservoir trout could serve as an egg source for rehabilitation of native trout in southeastern Oregon streams, where desirable. During spring more than 250 reservoir trout averaging 39.8 cm in length migrated into Threernile Creek to spawn, and provided excellent opportunity for anglers. Terminal reservoirs might be considered as management tools for trout populations in small streams, providing larger trout than the stream would normally produce. Such reservoirs could serve as multiple purpose water storage facilities for irrigation, stock watering, and trout production. The status of the trout populations studied was relatively good in stream sections that had not been disturbed by man's activities. Title: Biology and production of the red-band trout (Salmo sp.) in four southeastern Oregon streams Author: Kunkel, Clair The red-band trout is native to many small, isolated streams in southeastern Oregon. A study of the red-band population of Three- mile Creek and Reservoir was conducted from August 1973 to June 1975. Data were collected concerning population size, age composition, growth, biomass, recruitment, fecundity, and habitat. During the spring of 1975 similar data were collected for red-band populations in Home, Rattlesnake, and Buck creeks. The average trout biomass in Threemile Creek was 24.2 g/m2 and average production was 17.2 g/m2/yr. The production rate of 17.2 g/m2/yr is among the highest reported for salmonids in small streams and is probably in part due to the stable environment afforded by the springs which feed Threemile Creek. Biomass in the other study streams ranged from 2.4 to more than 6.7 g/m2 and production ranged from 1.2 to more than 4.2 g/m2/yr, not including production of age O-I fish. Trout biomass in Threemile Reservoir was 84 kg/ha in September 1974, and annual production was 80 kg/ha. The presence of the reservoir has increased the total production of the Threemile system by at least 12 times. Most female trout in the streams and reservoir matured at age III. Egg production in the Threemile system was considerably greater than in the other study streams. Spawners from the reservoir contributed nearly five times as many eggs to Threemile Creek as did the stream-dwelling females during the spring of 1974. The egg contribution of reservoir fish was probably greater than that required to perpetuate the observed trout densities in the stream. However, the resulting high density of fry may insure adequate contribution of young trout to the reservoir. Reservoir trout could serve as an egg source for rehabilitation of native trout in southeastern Oregon streams, where desirable. During spring more than 250 reservoir trout averaging 39.8 cm in length migrated into Threernile Creek to spawn, and provided excellent opportunity for anglers. Terminal reservoirs might be considered as management tools for trout populations in small streams, providing larger trout than the stream would normally produce. Such reservoirs could serve as multiple purpose water storage facilities for irrigation, stock watering, and trout production. The status of the trout populations studied was relatively good in stream sections that had not been disturbed by man's activities. Close

• 95. [Article] Biophysical factors driving the distribution and abundance of redband/steelhead trout (Oncorhynchus mykiss gairdneri) in the South Fork John Day River Basin, Oregon, USA

  The overall goal of this study was to identify multiple scales of habitat use and habitat electivity by redband/steelhead trout and define the limiting factors affecting the distribution patterns of this ...

  Citation × Citation Citation Abstract Copy Title: Biophysical factors driving the distribution and abundance of redband/steelhead trout (Oncorhynchus mykiss gairdneri) in the South Fork John Day River Basin, Oregon, USA Author: Madrinan, Luis Francisco The overall goal of this study was to identify multiple scales of habitat use and habitat electivity by redband/steelhead trout and define the limiting factors affecting the distribution patterns of this species during summer flows. The main objective in chapter 2 was to identify the most important habitat associations that control the distribution patterns of threatened populations of redband/steelhead trout in the South Fork John Day River Basin. I found that the factors influencing the distribution patterns of trout in the basin were dependent on the thermal context and spatial extent of analysis. The inclusion of water temperature alone at large spatial scales explained most of the distribution of trout at the basin scale and that channel morphology was a very important factor at small spatial scales. The main objective in chapter 3 was to identify geophysical factors influencing the distribution pattern of threatened populations of redband/steelhead trout in the basin at multiple spatial scales. I found that the trout distribution patterns in the area could be described as a clustered distribution, with a strong selection for upstream-cold water reaches and small, well oxygenated, running water pools. My study reveals that the most influential factor at large spatial scales was water temperature and smaller scale channel morphology. Chapter 4 examines whether longitudinal-summer-stream temperature profiles in semi arid-environment streams can be used to index carrying capacities of threatened populations of redband/steelhead trout. My results show that, in the South Fork John Day Basin, stream temperature can be used as indicator of trout carrying capacity. The distribution redband/steelhead trout in summer is largely determined by the- physiologically influenced-preference that individuals have for habitats within specific temperature ranges. Title: Biophysical factors driving the distribution and abundance of redband/steelhead trout (Oncorhynchus mykiss gairdneri) in the South Fork John Day River Basin, Oregon, USA Author: Madrinan, Luis Francisco The overall goal of this study was to identify multiple scales of habitat use and habitat electivity by redband/steelhead trout and define the limiting factors affecting the distribution patterns of this species during summer flows. The main objective in chapter 2 was to identify the most important habitat associations that control the distribution patterns of threatened populations of redband/steelhead trout in the South Fork John Day River Basin. I found that the factors influencing the distribution patterns of trout in the basin were dependent on the thermal context and spatial extent of analysis. The inclusion of water temperature alone at large spatial scales explained most of the distribution of trout at the basin scale and that channel morphology was a very important factor at small spatial scales. The main objective in chapter 3 was to identify geophysical factors influencing the distribution pattern of threatened populations of redband/steelhead trout in the basin at multiple spatial scales. I found that the trout distribution patterns in the area could be described as a clustered distribution, with a strong selection for upstream-cold water reaches and small, well oxygenated, running water pools. My study reveals that the most influential factor at large spatial scales was water temperature and smaller scale channel morphology. Chapter 4 examines whether longitudinal-summer-stream temperature profiles in semi arid-environment streams can be used to index carrying capacities of threatened populations of redband/steelhead trout. My results show that, in the South Fork John Day Basin, stream temperature can be used as indicator of trout carrying capacity. The distribution redband/steelhead trout in summer is largely determined by the- physiologically influenced-preference that individuals have for habitats within specific temperature ranges. Close

• 96. [Article] Distribution and characteristics of an isolated population of coastal cutthroat trout (Oncorhynchus clarki) in streams of Triangle Lake Basin, Oregon

  This research focused on features of a genetically isolated population of cutthroat trout (Oncorhynchus clarki) in the Triangle Lake basin of coastal Oregon. A falls at the outlet of Triangle Lake has ...

  Citation × Citation Citation Abstract Copy Title: Distribution and characteristics of an isolated population of coastal cutthroat trout (Oncorhynchus clarki) in streams of Triangle Lake Basin, Oregon Author: Hurley, Steven M. This research focused on features of a genetically isolated population of cutthroat trout (Oncorhynchus clarki) in the Triangle Lake basin of coastal Oregon. A falls at the outlet of Triangle Lake has blocked upstream migration of trout and anadromous salmonids into the basin. Cutthroat trout were found throughout the six study streams of the Triangle Lake basin in association with other native fishes and introduced warmwater fishes. Warmwater species (e.g. Centrarchidae) were restricted largely to the lakes of Triangle Lake basin, and did not comprise a significant part of the stream fish fauna. Salmonids and cottids dominated the upper forested reaches of the basin, whereas nonsalmonids dominated the lower reaches. The middle reaches contained a transitional fish community between the upper and lower reaches. Reach type was a major factor influencing cutthroat trout density and size distribution. Areal densities of cutthroat trout were highest in the upper reaches and lowest in the lower reaches with the exception of 0+ cutthroat trout, which occurred at similar densities in all reaches. The highest frequency of 1+ cutthroat trout occurred in the middle reaches, whereas the highest frequency of 0+ cutthroat occurred in the lower reaches. Within reaches, channel unit type influenced the density and age structure of cutthroat trout. Pools and rapids had the highest densities of cutthroat trout, whereas riffles, glides, and cascades had lower densities. Larger trout were found primarily in pools and rapids. Planted steelhead fry (Oncorhynchus mykiss) were found in two streams, Congdon Creek and Lake Creek. Although most steelhead fry leave the basin as smolts, some steelhead appear to become resident and may hybridize with native cutthroat trout. Cutthroat trout spawning was observed from late December 1987 through late May 1988. Differences in the time and place of spawning may serve to genetically isolate two populations of cutthroat trout in Triangle Lake basin. One population may be lake dwelling as adults and spawn lower in the basin in late spring. The other population may be stream dwelling and spawn in the winter during higher flows, which allows them to spawn in the upper reaches of the basin. Title: Distribution and characteristics of an isolated population of coastal cutthroat trout (Oncorhynchus clarki) in streams of Triangle Lake Basin, Oregon Author: Hurley, Steven M. This research focused on features of a genetically isolated population of cutthroat trout (Oncorhynchus clarki) in the Triangle Lake basin of coastal Oregon. A falls at the outlet of Triangle Lake has blocked upstream migration of trout and anadromous salmonids into the basin. Cutthroat trout were found throughout the six study streams of the Triangle Lake basin in association with other native fishes and introduced warmwater fishes. Warmwater species (e.g. Centrarchidae) were restricted largely to the lakes of Triangle Lake basin, and did not comprise a significant part of the stream fish fauna. Salmonids and cottids dominated the upper forested reaches of the basin, whereas nonsalmonids dominated the lower reaches. The middle reaches contained a transitional fish community between the upper and lower reaches. Reach type was a major factor influencing cutthroat trout density and size distribution. Areal densities of cutthroat trout were highest in the upper reaches and lowest in the lower reaches with the exception of 0+ cutthroat trout, which occurred at similar densities in all reaches. The highest frequency of 1+ cutthroat trout occurred in the middle reaches, whereas the highest frequency of 0+ cutthroat occurred in the lower reaches. Within reaches, channel unit type influenced the density and age structure of cutthroat trout. Pools and rapids had the highest densities of cutthroat trout, whereas riffles, glides, and cascades had lower densities. Larger trout were found primarily in pools and rapids. Planted steelhead fry (Oncorhynchus mykiss) were found in two streams, Congdon Creek and Lake Creek. Although most steelhead fry leave the basin as smolts, some steelhead appear to become resident and may hybridize with native cutthroat trout. Cutthroat trout spawning was observed from late December 1987 through late May 1988. Differences in the time and place of spawning may serve to genetically isolate two populations of cutthroat trout in Triangle Lake basin. One population may be lake dwelling as adults and spawn lower in the basin in late spring. The other population may be stream dwelling and spawn in the winter during higher flows, which allows them to spawn in the upper reaches of the basin. Close

• 97. [Article] Effects of kokanee (Oncorhynchus nerka) redd superimposition on bull trout (Salvelinus confluentus) reproductive success in the Deschutes River Basin, Oregon.

  Oregon's only remaining non-reservoir population of adfluvial bull trout (Salvelinus confluentus) is found in Odell Lake, in the headwaters of the Deschutes River. The population size is unknown, but ...

  Citation × Citation Citation Abstract Copy Title: Effects of kokanee (Oncorhynchus nerka) redd superimposition on bull trout (Salvelinus confluentus) reproductive success in the Deschutes River Basin, Oregon. Author: Weeber, Matthew A. Oregon's only remaining non-reservoir population of adfluvial bull trout (Salvelinus confluentus) is found in Odell Lake, in the headwaters of the Deschutes River. The population size is unknown, but appears to be quite small. Limited spawning and rearing habitats, combined with the effects of introduced species and other anthropogenic changes to the basin have raised concerns as to the population's viability. The lower section of Trapper Creek, a tributary of Odell Lake, is the only known spawning habitat used by this species throughout the system. Large numbers of kokanee salmon (Oncorhynchus nerka) also spawn in the same reach, superimposing their redds on those dug earlier by bull trout. After superimposition by kokanee, bull trout redds are virtually undetectable. The objective of the study was to assess the effect of kokanee redd superimposition on bull trout egg-to-fry survival. Due to uncertainty in the size of the Odell Lake bull trout population much of the study was conducted on bull trout and kokanee of the Metolius River system, a neiboring Deschutes sub-basin. Emergent fry traps were used, in combination with egg burial depth measurements, scour monitors, and gravel characterization to establish actual physical overlap between both species and degree of bull trout egg pocket disturbance caused by kokanee. Results indicate that most bull trout egg pockets are dug deeper than depths reached by spawning kokanee. Kokanee were found to be very superficial spawners in the streams studied. Bull trout fry emergence data suggest that kokanee redd superimposition does not affect egg-to-fry survival rates. Title: Effects of kokanee (Oncorhynchus nerka) redd superimposition on bull trout (Salvelinus confluentus) reproductive success in the Deschutes River Basin, Oregon. Author: Weeber, Matthew A. Oregon's only remaining non-reservoir population of adfluvial bull trout (Salvelinus confluentus) is found in Odell Lake, in the headwaters of the Deschutes River. The population size is unknown, but appears to be quite small. Limited spawning and rearing habitats, combined with the effects of introduced species and other anthropogenic changes to the basin have raised concerns as to the population's viability. The lower section of Trapper Creek, a tributary of Odell Lake, is the only known spawning habitat used by this species throughout the system. Large numbers of kokanee salmon (Oncorhynchus nerka) also spawn in the same reach, superimposing their redds on those dug earlier by bull trout. After superimposition by kokanee, bull trout redds are virtually undetectable. The objective of the study was to assess the effect of kokanee redd superimposition on bull trout egg-to-fry survival. Due to uncertainty in the size of the Odell Lake bull trout population much of the study was conducted on bull trout and kokanee of the Metolius River system, a neiboring Deschutes sub-basin. Emergent fry traps were used, in combination with egg burial depth measurements, scour monitors, and gravel characterization to establish actual physical overlap between both species and degree of bull trout egg pocket disturbance caused by kokanee. Results indicate that most bull trout egg pockets are dug deeper than depths reached by spawning kokanee. Kokanee were found to be very superficial spawners in the streams studied. Bull trout fry emergence data suggest that kokanee redd superimposition does not affect egg-to-fry survival rates. Close

• 98. [Article] Life-history organization of cutthroat trout in Yellowstone Lake and its management implications

  Life-history organization of the cutthroat trout (Oncorhvnchus clarki) may be viewed at various levels, including species, subspecies, metapopulation, population, or individual. Each level varies in spatial ...

  Citation × Citation Citation Abstract Copy Title: Life-history organization of cutthroat trout in Yellowstone Lake and its management implications Author: Gresswell, Robert E. Life-history organization of the cutthroat trout (Oncorhvnchus clarki) may be viewed at various levels, including species, subspecies, metapopulation, population, or individual. Each level varies in spatial scale and temporal persistence, and components at each level continually change with changes in environment. Cutthroat trout are widely distributed throughout the western USA, and during its evolution the species has organized into fourteen subspecies with many different life-history characteristics and habitat requirements. Within subspecies, organization is equally complex. For example, life-history traits, such as average size and age, migration strategy, and migration timing, vary among individual spawning populations of Yellowstone cutthroat trout (Oncorhvnchus clarki bouvieri) in tributary streams of Yellowstone Lake. In this study specific life-history traits of adfluvial cutthroat trout spawners from Yellowstone Lake were examined in relation to habitat of tributary drainages and subbasins of the lake. Results suggest that stream drainages vary along gradients that can be described by mean aspect, mean elevation, and drainage size. Approximately two-thirds of the variation in the timing of annual cutthroat trout spawning migrations and average size of spawners can be described by third-degree polynomial regressions with mean aspect and elevation as predictor variables. Differences in average size and growth of cutthroat trout suggested metapopulation substructure related spatial heterogeneity of environmental characteristics of individual lake subbasins. Evidence that polytypic species can adapt to heterogenous environments, even within a single lake, has implications for the conservation, restoration, and management of many freshwater fishes. Understanding the consequences of human perturbations on life-history organization is critical for management of the cutthroat trout and other polytypic salmonid species. Loss of diversity at the any hierarchical level jeopardizes long-term ability of the species to adapt to changing environments, and it may also lead to increased fluctuations in abundance and yield and increase risk of extinction. Recent emphasis on a holistic view of natural systems and their management is associated with a growing appreciation of the role of human values in these systems. The recreational fishery for Yellowstone cutthroat trout in Yellowstone National Park is an example of the effects of management on a natural-cultural system. Although angler harvest has been drastically reduced or prohibited, the recreational value of Yellowstone cutthroat trout estimated by angling factors (e.g., landing rate or size) ranks above all other sport species in Yellowstone National Park. To maintain an indigenous fishery resource of this quality with hatchery propagation is not economically or technically feasible. Nonconsumptive uses of the Yellowstone cutthroat trout including fish-watching and intangible values, such as existence demand, provide additional support for protection of wild Yellowstone cutthroat trout populations. A management strategy that reduces resource extraction has provided a means to sustain a quality recreational fishery while enhancing values associated with the protection of natural systems. Title: Life-history organization of cutthroat trout in Yellowstone Lake and its management implications Author: Gresswell, Robert E. Life-history organization of the cutthroat trout (Oncorhvnchus clarki) may be viewed at various levels, including species, subspecies, metapopulation, population, or individual. Each level varies in spatial scale and temporal persistence, and components at each level continually change with changes in environment. Cutthroat trout are widely distributed throughout the western USA, and during its evolution the species has organized into fourteen subspecies with many different life-history characteristics and habitat requirements. Within subspecies, organization is equally complex. For example, life-history traits, such as average size and age, migration strategy, and migration timing, vary among individual spawning populations of Yellowstone cutthroat trout (Oncorhvnchus clarki bouvieri) in tributary streams of Yellowstone Lake. In this study specific life-history traits of adfluvial cutthroat trout spawners from Yellowstone Lake were examined in relation to habitat of tributary drainages and subbasins of the lake. Results suggest that stream drainages vary along gradients that can be described by mean aspect, mean elevation, and drainage size. Approximately two-thirds of the variation in the timing of annual cutthroat trout spawning migrations and average size of spawners can be described by third-degree polynomial regressions with mean aspect and elevation as predictor variables. Differences in average size and growth of cutthroat trout suggested metapopulation substructure related spatial heterogeneity of environmental characteristics of individual lake subbasins. Evidence that polytypic species can adapt to heterogenous environments, even within a single lake, has implications for the conservation, restoration, and management of many freshwater fishes. Understanding the consequences of human perturbations on life-history organization is critical for management of the cutthroat trout and other polytypic salmonid species. Loss of diversity at the any hierarchical level jeopardizes long-term ability of the species to adapt to changing environments, and it may also lead to increased fluctuations in abundance and yield and increase risk of extinction. Recent emphasis on a holistic view of natural systems and their management is associated with a growing appreciation of the role of human values in these systems. The recreational fishery for Yellowstone cutthroat trout in Yellowstone National Park is an example of the effects of management on a natural-cultural system. Although angler harvest has been drastically reduced or prohibited, the recreational value of Yellowstone cutthroat trout estimated by angling factors (e.g., landing rate or size) ranks above all other sport species in Yellowstone National Park. To maintain an indigenous fishery resource of this quality with hatchery propagation is not economically or technically feasible. Nonconsumptive uses of the Yellowstone cutthroat trout including fish-watching and intangible values, such as existence demand, provide additional support for protection of wild Yellowstone cutthroat trout populations. A management strategy that reduces resource extraction has provided a means to sustain a quality recreational fishery while enhancing values associated with the protection of natural systems. Close

• 99. [Article] Ecological relation of sympatric steelhead and resident rainbow trout in the Deschutes River, Oregon

  Sympatric steelhead and resident rainbow trout (Oncorhynchus mykiss) are known to exist in many rivers throughout the Pacific Rim. Whether sympatric steelhead and resident rainbow trout are polymorphisms ...

  Citation × Citation Citation Abstract Copy Title: Ecological relation of sympatric steelhead and resident rainbow trout in the Deschutes River, Oregon Author: Zimmerman, Christian E. Sympatric steelhead and resident rainbow trout (Oncorhynchus mykiss) are known to exist in many rivers throughout the Pacific Rim. Whether sympatric steelhead and resident rainbow trout are polymorphisms within a single gene pool or two reproductively isolated populations has significant implications concerning the study and conservation of this polytypic species. I examined population structure and use of spawning and rearing habitats by steelhead and resident rainbow trout in the Deschutes River, Oregon. I used otolith microchemistry to determine the maternal origin (steelhead verses resident) of adult steelhead and resident rainbow trout based on Sr/Ca ratios in primordia and freshwater growth regions of otoliths. Only steelhead of steelhead origin and resident rainbow trout of resident origin were encountered. In the Babine River of British Columbia, however, steelhead of resident origin and resident rainbow trout of steelhead origin were present. Temporal and spatial segregation of spawning habitat served to limit breeding between steelhead and resident rainbow trout in the mainstem Deschutes River. The timing of 50% spawning by steelhead occurred 9 to 10 weeks earlier than by resident rainbow trout. Steelhead spawning sites were deeper and of larger substrate than those used by resident rainbow trout. There was an overlap in the timing of emergence by steelhead and resident rainbow trout fry in the mainstem Deschutes River, but higher levels of aggression and territoriality characterize newly emerged steelhead fry. Determination of maternal origin based on otolith microchemistry indicated that young-of- year 0. mykiss in small hydrologically unstable tributaries to the Deschutes River were exclusively the progeny of steelhead. Progeny of resident rainbow trout numerically dominated mainstem-rearing habitats. Based on the degree of segregation between steelhead and resident rainbow trout, the two life history forms act as two separate species in the Deschutes River. This relationship has significant implications concerning the restoration and conservation of steelhead and resident rainbow trout. Where steelhead and resident rainbow trout constitute reproductively isolated populations, conservation of both life history forms within the species cannot be achieved unless both populations are maintained. Title: Ecological relation of sympatric steelhead and resident rainbow trout in the Deschutes River, Oregon Author: Zimmerman, Christian E. Sympatric steelhead and resident rainbow trout (Oncorhynchus mykiss) are known to exist in many rivers throughout the Pacific Rim. Whether sympatric steelhead and resident rainbow trout are polymorphisms within a single gene pool or two reproductively isolated populations has significant implications concerning the study and conservation of this polytypic species. I examined population structure and use of spawning and rearing habitats by steelhead and resident rainbow trout in the Deschutes River, Oregon. I used otolith microchemistry to determine the maternal origin (steelhead verses resident) of adult steelhead and resident rainbow trout based on Sr/Ca ratios in primordia and freshwater growth regions of otoliths. Only steelhead of steelhead origin and resident rainbow trout of resident origin were encountered. In the Babine River of British Columbia, however, steelhead of resident origin and resident rainbow trout of steelhead origin were present. Temporal and spatial segregation of spawning habitat served to limit breeding between steelhead and resident rainbow trout in the mainstem Deschutes River. The timing of 50% spawning by steelhead occurred 9 to 10 weeks earlier than by resident rainbow trout. Steelhead spawning sites were deeper and of larger substrate than those used by resident rainbow trout. There was an overlap in the timing of emergence by steelhead and resident rainbow trout fry in the mainstem Deschutes River, but higher levels of aggression and territoriality characterize newly emerged steelhead fry. Determination of maternal origin based on otolith microchemistry indicated that young-of- year 0. mykiss in small hydrologically unstable tributaries to the Deschutes River were exclusively the progeny of steelhead. Progeny of resident rainbow trout numerically dominated mainstem-rearing habitats. Based on the degree of segregation between steelhead and resident rainbow trout, the two life history forms act as two separate species in the Deschutes River. This relationship has significant implications concerning the restoration and conservation of steelhead and resident rainbow trout. Where steelhead and resident rainbow trout constitute reproductively isolated populations, conservation of both life history forms within the species cannot be achieved unless both populations are maintained. Close

• 100. [Image] Bull Trout, Salvelinus Confluentus... Draft Recovery Plan, Chapter 2, Klamath River Recovery Unit...U.S. Department Of The Interior

  	KLAMATH RIVER RECOVERY UNIT CHAPTER OF THE BULL TROUT RECOVERY PLAN EXECUTIVE SUMMARY CURRENT SPECIES STATUS Klamath River bull trout were listed as a distinct population segment ...
  	Citation × Citation Citation Abstract Copy Title: Bull Trout, Salvelinus Confluentus... Draft Recovery Plan, Chapter 2, Klamath River Recovery Unit...U.S. Department Of The Interior Year: 2008, 2005 KLAMATH RIVER RECOVERY UNIT CHAPTER OF THE BULL TROUT RECOVERY PLAN EXECUTIVE SUMMARY CURRENT SPECIES STATUS Klamath River bull trout were listed as a distinct population segment in 1998 (63 FR 31647) because they are physically isolated from other bull trout by the Pacific Ocean and several small mountain ranges in central Oregon. Recovery of bull trout in the Klamath River Recovery Unit, which includes three core areas and nine currently identified local populations, will require cooperation from Federal, State, and local agencies, and Tribal and private entities. Within the Klamath River Recovery Unit, abundance has been severely reduced and remaining populations are fragmented. HABITAT REQUIREMENTS AND LIMITING FACTORS Watershed disruption has played a major role in the decline of bull trout in the Klamath River basin. The effects of historical land use on fish habitat in the larger tributaries and mainstem rivers of the Klamath River basin have been profound. Channelization, water withdrawals, removal of streamside vegetation, and other disturbances have altered the aquatic environment by elevating water temperatures, reducing water quantity and quality, and increasing sedimentation. Changes in or disruptions to watershed processes that influence characteristics of stream channels have also influenced the dynamics and persistence of bull trout populations. Klamath River basin bull trout are threatened by habitat degradation, past and present land use management practices, agricultural water diversions, and competition or hybridization from normative brown and brook trout. As a result of past land and resource management practices, bull trout populations in the Klamath River Recovery Unit are small, disjunct, and face a high risk of extirpation. IV RECOVERY GOAL AND OBJECTIVES The goal of the bull trout recovery plan is to ensure the long-term persistence of self-sustaining, complex interacting groups of bull trout distributed across the species range, so that the species can be delisted. In order to recover bull trout in the Klamath River, the following objectives need to be met: ? Maintain current distribution of bull trout and restore distribution in previously occupied areas within the Klamath River Recovery Unit, as noted in Appendix A. ? Maintain stable or increasing trends in abundance of bull trout within the Klamath River. This objective includes the expression of all life history strategies including resident, fluvial, and adfluvial forms in the Upper Klamath Lake core area and resident and fluvial forms in the Sycan River and Upper Sprague River core areas. ? Restore and maintain suitable habitat conditions for all bull trout life history stages and strategies. In core areas and migration corridors, stable or upward trends in habitat quality are achieved through landscape-level adjustments in land management strategies designed to maintain and/or enhance structural and functional attributes of upslope, riparian, and fluvial systems. ? Conserve genetic diversity and provide opportunity for interchange of genetic material among appropriate core populations. RECOVERY CRITERIA Recovery criteria for the Klamath River Recovery Unit reflect the stated objectives and consideration of population and habitat characteristics within the recovery unit. Using four population and habitat elements, the Klamath River Recovery Unit Team categorized bull trout into three groups of relative risk: diminished, intermediate, and increased. Team members evaluated bull trout under current and potential recovered conditions based on the number of local populations, adult abundance, population trends and variability, and connectivity of the system. These elements were derived from the best scientific information available concerning bull trout population and habitat requirements. Evaluation of these elements under a recovered condition assumed that actions identified within this chapter had been implemented. 1. Distribution criteria will be met when current distribution of bull trout in the 12 local populations is maintained and distribution is expanded by establishing bull trout in areas identified as suitable for potential local populations. The number of existing local populations by core area are as follows: Upper Klamath Lake, 3; Sycan River, 2; and Upper Sprague River, 7. Achieving criterion 1 entails maintaining existing local populations and establishing additional potential local populations in all core areas in the recovery unit to maintain current and recovered distribution. To achieve criterion 1 and to ensure a core area population of no fewer than 100 adult bull trout, establishing at least 5 to 7 local populations in the Klamath Lake core area among 15 potential local populations (2 to 5 new local populations), at least 5 to 7 local populations in the Sycan River core area from among 15 potential local populations (3 to 5 new local populations), and at least 10 to 12 local populations in the Upper Sprague River core area from among 25 potential local populations (3 to 5 new local populations) is necessary. 2. Abundance criteria will be met when the estimated number of adult bull trout is at least 8,250 individuals distributed among the Upper Klamath Lake, Sycan River, and Upper Sprague River core areas, based on 10 years of monitoring data. 3. Trend criteria will be met when adult bull trout exhibit stable or increasing trends in abundance in the Upper Klamath Lake, Sycan River, and Upper Sprague River core areas, based on 2 generations (10 years) of monitoring data. VI 4. Connectivity criteria will be met when specific barriers to bull trout migration in the Klamath River Recovery Unit have been addressed. In the Klamath River Recovery Unit, this objective means addressing passage: 1) existing culverts that impede passage should be replaced, including those on Threemile Creek at U.S. Forest Service Road 110 crossing, Brownsworth Creek at U.S. Forest Service Road 34 crossing, and Brownsworth Creek both 0.75 mile and 1.25 miles above U.S. Forest Service Road 34; the culvert 0.25 mile below U.S. Forest Service Road 34 (to prevent repeated washout); the large-diameter culvert at the Boulder Creek road crossing; culverts in the upper Sycan River watershed that are identified in the Fremont National Forest inventory; and several in the North Fork Sprague River drainage, namely, on North Fork Sprague River (2), Boulder Creek (1), Dead Cow Creek (1), and Sheepy Creek (1); 2) fish passage structures should be installed at water diversions on bull trout streams, and barriers should be removed, including on Cherry, Sevenmile, Sun, and Threemile Creeks; 3) fish screens should be installed to prevent fish from entering diversion canals or pipes, including on Long, Deming, Threemile, Sun, Sevenmile, and Cherry Creeks; 4) manmade barriers and entrainment should be evaluated and remedied to promote migratory bull trout; priority watersheds include Threemile, Long, Deming, Sevenmile, Cherry, Sun, and Long Creeks. The Klamath River Recovery Unit team expects that the recovery process will be dynamic and will be refined as more information becomes available. Future adaptive management will play a major role in recovery implementation and refinement of recovery criteria. The recovery unit criteria listed above will be used to determine when the Klamath River Recovery Unit is fully contributing to recovery of the Klamath River population segment. vn ACTIONS NEEDED Recovery for bull trout will entail reducing threats to the long-term persistence of populations and their habitats, ensuring the security of multiple interacting groups of bull trout, and providing habitat and access to conditions that allow for the expression of various life history forms. The seven categories are listed in Chapter 1; tasks specific to this recovery unit are provided in this chapter. ESTIMATED COST OF RECOVERY Total cost of bull trout recovery in the Klamath River Recovery Unit is estimated at about $26 million spread over a 25-year recovery period. Successful recovery of bull trout in the recovery unit is contingent on removing threats from nonnative species, eliminating barriers to fish movement, and improving habitat conditions within the Klamath River basin. Total cost includes estimates of expenditures by local, Tribal, State, and Federal governments and by private business and individuals. Cost estimates are not provided for tasks which are normal agency responsibilities under existing authorities. The estimated costs are attributed to bull trout conservation, but other aquatic species will also benefit. ESTIMATED DATE OF RECOVERY Time required to achieve recovery depends on bull trout status, factors affecting bull trout, implementation and effectiveness of recovery tasks, and responses to recovery tasks. A tremendous amount of work will be required to restore impaired habitat, reconnect habitat, and eliminate threats from nonnative species. Three to five bull trout generations (15 to 25 years), or possibly longer, may be necessary before identified threats to the species can be significantly reduced and bull trout can be considered eligible for delisting. vin Title: Bull Trout, Salvelinus Confluentus... Draft Recovery Plan, Chapter 2, Klamath River Recovery Unit...U.S. Department Of The Interior Year: 2008, 2005 KLAMATH RIVER RECOVERY UNIT CHAPTER OF THE BULL TROUT RECOVERY PLAN EXECUTIVE SUMMARY CURRENT SPECIES STATUS Klamath River bull trout were listed as a distinct population segment in 1998 (63 FR 31647) because they are physically isolated from other bull trout by the Pacific Ocean and several small mountain ranges in central Oregon. Recovery of bull trout in the Klamath River Recovery Unit, which includes three core areas and nine currently identified local populations, will require cooperation from Federal, State, and local agencies, and Tribal and private entities. Within the Klamath River Recovery Unit, abundance has been severely reduced and remaining populations are fragmented. HABITAT REQUIREMENTS AND LIMITING FACTORS Watershed disruption has played a major role in the decline of bull trout in the Klamath River basin. The effects of historical land use on fish habitat in the larger tributaries and mainstem rivers of the Klamath River basin have been profound. Channelization, water withdrawals, removal of streamside vegetation, and other disturbances have altered the aquatic environment by elevating water temperatures, reducing water quantity and quality, and increasing sedimentation. Changes in or disruptions to watershed processes that influence characteristics of stream channels have also influenced the dynamics and persistence of bull trout populations. Klamath River basin bull trout are threatened by habitat degradation, past and present land use management practices, agricultural water diversions, and competition or hybridization from normative brown and brook trout. As a result of past land and resource management practices, bull trout populations in the Klamath River Recovery Unit are small, disjunct, and face a high risk of extirpation. IV RECOVERY GOAL AND OBJECTIVES The goal of the bull trout recovery plan is to ensure the long-term persistence of self-sustaining, complex interacting groups of bull trout distributed across the species range, so that the species can be delisted. In order to recover bull trout in the Klamath River, the following objectives need to be met: ? Maintain current distribution of bull trout and restore distribution in previously occupied areas within the Klamath River Recovery Unit, as noted in Appendix A. ? Maintain stable or increasing trends in abundance of bull trout within the Klamath River. This objective includes the expression of all life history strategies including resident, fluvial, and adfluvial forms in the Upper Klamath Lake core area and resident and fluvial forms in the Sycan River and Upper Sprague River core areas. ? Restore and maintain suitable habitat conditions for all bull trout life history stages and strategies. In core areas and migration corridors, stable or upward trends in habitat quality are achieved through landscape-level adjustments in land management strategies designed to maintain and/or enhance structural and functional attributes of upslope, riparian, and fluvial systems. ? Conserve genetic diversity and provide opportunity for interchange of genetic material among appropriate core populations. RECOVERY CRITERIA Recovery criteria for the Klamath River Recovery Unit reflect the stated objectives and consideration of population and habitat characteristics within the recovery unit. Using four population and habitat elements, the Klamath River Recovery Unit Team categorized bull trout into three groups of relative risk: diminished, intermediate, and increased. Team members evaluated bull trout under current and potential recovered conditions based on the number of local populations, adult abundance, population trends and variability, and connectivity of the system. These elements were derived from the best scientific information available concerning bull trout population and habitat requirements. Evaluation of these elements under a recovered condition assumed that actions identified within this chapter had been implemented. 1. Distribution criteria will be met when current distribution of bull trout in the 12 local populations is maintained and distribution is expanded by establishing bull trout in areas identified as suitable for potential local populations. The number of existing local populations by core area are as follows: Upper Klamath Lake, 3; Sycan River, 2; and Upper Sprague River, 7. Achieving criterion 1 entails maintaining existing local populations and establishing additional potential local populations in all core areas in the recovery unit to maintain current and recovered distribution. To achieve criterion 1 and to ensure a core area population of no fewer than 100 adult bull trout, establishing at least 5 to 7 local populations in the Klamath Lake core area among 15 potential local populations (2 to 5 new local populations), at least 5 to 7 local populations in the Sycan River core area from among 15 potential local populations (3 to 5 new local populations), and at least 10 to 12 local populations in the Upper Sprague River core area from among 25 potential local populations (3 to 5 new local populations) is necessary. 2. Abundance criteria will be met when the estimated number of adult bull trout is at least 8,250 individuals distributed among the Upper Klamath Lake, Sycan River, and Upper Sprague River core areas, based on 10 years of monitoring data. 3. Trend criteria will be met when adult bull trout exhibit stable or increasing trends in abundance in the Upper Klamath Lake, Sycan River, and Upper Sprague River core areas, based on 2 generations (10 years) of monitoring data. VI 4. Connectivity criteria will be met when specific barriers to bull trout migration in the Klamath River Recovery Unit have been addressed. In the Klamath River Recovery Unit, this objective means addressing passage: 1) existing culverts that impede passage should be replaced, including those on Threemile Creek at U.S. Forest Service Road 110 crossing, Brownsworth Creek at U.S. Forest Service Road 34 crossing, and Brownsworth Creek both 0.75 mile and 1.25 miles above U.S. Forest Service Road 34; the culvert 0.25 mile below U.S. Forest Service Road 34 (to prevent repeated washout); the large-diameter culvert at the Boulder Creek road crossing; culverts in the upper Sycan River watershed that are identified in the Fremont National Forest inventory; and several in the North Fork Sprague River drainage, namely, on North Fork Sprague River (2), Boulder Creek (1), Dead Cow Creek (1), and Sheepy Creek (1); 2) fish passage structures should be installed at water diversions on bull trout streams, and barriers should be removed, including on Cherry, Sevenmile, Sun, and Threemile Creeks; 3) fish screens should be installed to prevent fish from entering diversion canals or pipes, including on Long, Deming, Threemile, Sun, Sevenmile, and Cherry Creeks; 4) manmade barriers and entrainment should be evaluated and remedied to promote migratory bull trout; priority watersheds include Threemile, Long, Deming, Sevenmile, Cherry, Sun, and Long Creeks. The Klamath River Recovery Unit team expects that the recovery process will be dynamic and will be refined as more information becomes available. Future adaptive management will play a major role in recovery implementation and refinement of recovery criteria. The recovery unit criteria listed above will be used to determine when the Klamath River Recovery Unit is fully contributing to recovery of the Klamath River population segment. vn ACTIONS NEEDED Recovery for bull trout will entail reducing threats to the long-term persistence of populations and their habitats, ensuring the security of multiple interacting groups of bull trout, and providing habitat and access to conditions that allow for the expression of various life history forms. The seven categories are listed in Chapter 1; tasks specific to this recovery unit are provided in this chapter. ESTIMATED COST OF RECOVERY Total cost of bull trout recovery in the Klamath River Recovery Unit is estimated at about $26 million spread over a 25-year recovery period. Successful recovery of bull trout in the recovery unit is contingent on removing threats from nonnative species, eliminating barriers to fish movement, and improving habitat conditions within the Klamath River basin. Total cost includes estimates of expenditures by local, Tribal, State, and Federal governments and by private business and individuals. Cost estimates are not provided for tasks which are normal agency responsibilities under existing authorities. The estimated costs are attributed to bull trout conservation, but other aquatic species will also benefit. ESTIMATED DATE OF RECOVERY Time required to achieve recovery depends on bull trout status, factors affecting bull trout, implementation and effectiveness of recovery tasks, and responses to recovery tasks. A tremendous amount of work will be required to restore impaired habitat, reconnect habitat, and eliminate threats from nonnative species. Three to five bull trout generations (15 to 25 years), or possibly longer, may be necessary before identified threats to the species can be significantly reduced and bull trout can be considered eligible for delisting. vin Close