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• 81. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2003 Annual Progress Report

  Abstract -- This report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2003. The main objectives of this report are to document and evaluate ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2003 Annual Progress Report Abstract -- This report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2003. The main objectives of this report are to document and evaluate salmon culture performance for spring Chinook salmon hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, and smolt-to-adult survival rate, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2001 cohort of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics for the 2003 return of adult Chinook salmon, and the collection of eggs for the 2003 cohort. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2003 Annual Progress Report Abstract -- This report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2003. The main objectives of this report are to document and evaluate salmon culture performance for spring Chinook salmon hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, and smolt-to-adult survival rate, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2001 cohort of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics for the 2003 return of adult Chinook salmon, and the collection of eggs for the 2003 cohort. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 82. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2004 Annual Progress Report

  Abstract -- This report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2004. Also summarized are adult broodstock monitoring data collected ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2004 Annual Progress Report Abstract -- This report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2004. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, and smolt-to-adult survival rate, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2002 brood year of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics for the 2004 return of adult Chinook salmon, and the collection of eggs for the 2004 brood year. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2004 Annual Progress Report Abstract -- This report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2004. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, and smolt-to-adult survival rate, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2002 brood year of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics for the 2004 return of adult Chinook salmon, and the collection of eggs for the 2004 brood year. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 83. [Article] Work Completed for Compliance with the Biological Opinion for Hatchery Programs in the Willamette Basin USACE funding: 2004 Annual Report

  Abstract -- The National Marine Fisheries Service (NMFS) has listed spring chinook salmon(Oncorhynchus tshawytscha) and winter steelhead (O. mykiss) in the Upper Willamette River Evolutionarily Significant ...

  Citation × Citation Citation Abstract Copy Title: Work Completed for Compliance with the Biological Opinion for Hatchery Programs in the Willamette Basin USACE funding: 2004 Annual Report Abstract -- The National Marine Fisheries Service (NMFS) has listed spring chinook salmon(Oncorhynchus tshawytscha) and winter steelhead (O. mykiss) in the Upper Willamette River Evolutionarily Significant Unit (ESU) as threatened under the Endangered Species Act (ESA; 64 FRN 14308; 64 FRN 14517). Concomitant with this listing, any actions taken or funded by a federal agency must be evaluated to assess whether these actions are likely to jeopardize the continued existence of threatened and endangered species, or result in the destruction or impairment of critical habitat. Several fish hatcheries operate within the ESU and may impact wild populations of listed species. Although all of the artificial propagation programs that potentially affect listed salmonids in the Upper Willamette River ESUs are operated by the Oregon Department of Fish and Wildlife(ODFW), 90% of the funding for these operations comes from the U.S. Army Corps of Engineers (COE). Possible risks of artificial propagation programs have been well documented. Hazards include disease transfer, competition for food and spawning sites, increased predation,increased incidental mortality from harvest, loss of genetic variability, genetic drift, and domestication (Steward and Bjornn 1990; Hard et al. 1992; Cuenco et al. 1993; Busack and Currens 1995; NRC 1996; and Waples 1999). Hatcheries can also play a positive role for wild salmonids by bolstering populations, especially those on the verge of extirpation, providing a genetic reserve in the case of extirpation, and providing opportunities for nutrient enrichment of streams (Steward and Bjornn 1990; Cuenco et al. 1993). The objective of this project is to evaluate the potential effects of hatchery programs on naturally spawning populations of spring chinook and winter steelhead within the Upper Willamette River ESU. The project employs four types of activities to achieve this goal: sampling of returns to hatcheries, creels to assess fisheries, monitoring of adult and juvenile migration through the use of traps and video observations, and monitoring natural production through spawning ground surveys. Title: Work Completed for Compliance with the Biological Opinion for Hatchery Programs in the Willamette Basin USACE funding: 2004 Annual Report Abstract -- The National Marine Fisheries Service (NMFS) has listed spring chinook salmon(Oncorhynchus tshawytscha) and winter steelhead (O. mykiss) in the Upper Willamette River Evolutionarily Significant Unit (ESU) as threatened under the Endangered Species Act (ESA; 64 FRN 14308; 64 FRN 14517). Concomitant with this listing, any actions taken or funded by a federal agency must be evaluated to assess whether these actions are likely to jeopardize the continued existence of threatened and endangered species, or result in the destruction or impairment of critical habitat. Several fish hatcheries operate within the ESU and may impact wild populations of listed species. Although all of the artificial propagation programs that potentially affect listed salmonids in the Upper Willamette River ESUs are operated by the Oregon Department of Fish and Wildlife(ODFW), 90% of the funding for these operations comes from the U.S. Army Corps of Engineers (COE). Possible risks of artificial propagation programs have been well documented. Hazards include disease transfer, competition for food and spawning sites, increased predation,increased incidental mortality from harvest, loss of genetic variability, genetic drift, and domestication (Steward and Bjornn 1990; Hard et al. 1992; Cuenco et al. 1993; Busack and Currens 1995; NRC 1996; and Waples 1999). Hatcheries can also play a positive role for wild salmonids by bolstering populations, especially those on the verge of extirpation, providing a genetic reserve in the case of extirpation, and providing opportunities for nutrient enrichment of streams (Steward and Bjornn 1990; Cuenco et al. 1993). The objective of this project is to evaluate the potential effects of hatchery programs on naturally spawning populations of spring chinook and winter steelhead within the Upper Willamette River ESU. The project employs four types of activities to achieve this goal: sampling of returns to hatcheries, creels to assess fisheries, monitoring of adult and juvenile migration through the use of traps and video observations, and monitoring natural production through spawning ground surveys. Close

• 84. [Article] Effects of Current Hatchery Practices on Salmon Odor Recognition and Responses

  Salmon hatcheries have been utilized throughout the Pacific Northwest for many decades to mitigate losses, supplement natural spawning populations, and to provide tribal, sport and commercial fishing opportunities. ...

  Citation × Citation Citation Abstract Copy Title: Effects of Current Hatchery Practices on Salmon Odor Recognition and Responses Author: Lemanski, Joseph R. Salmon hatcheries have been utilized throughout the Pacific Northwest for many decades to mitigate losses, supplement natural spawning populations, and to provide tribal, sport and commercial fishing opportunities. Currently, there is substantial debate on their efficacy and the potential threats hatchery-reared salmonids pose to natural populations. These concerns have lead to a large body of scientific investigation. The potential impacts hatchery-reared salmon may have on natural spawning populations can take many forms, such as competition, predation, and genetic introgression. Many of these issues arise from straying of hatchery-reared salmon from target return locations into areas where naturally spawning populations of salmon occur. In my thesis, I considered two questions related to hatchery practices and straying of hatchery-reared salmon. First, I addressed whether exposure to unfamiliar conspecifics during incubation (embryonic development) affects the population recognition responses of emergent steelhead (Oncorhynchus mykiss). I then examined whether dissolved free amino acids (DFAAs, chemicals believed to be important for natal stream identification in salmonids) are significantly altered as water sourced from a river passes through a salmon hatchery. The results of my first study suggested that newly emergent steelhead showed no preference for water conditioned by either familiar (fish from the same population) or unfamiliar (fish from geographically separate population) populations. These results suggest that exposure to unfamiliar or unrelated population specific odors during incubation in a hatchery may not have any significant effects on population recognition responses. The data from my second study suggested that both hatchery and river water DFAA profiles are very similar. I hypothesize that straying observed in hatchery-reared salmon may be due in part to a lack of a unique, distinguishable odor profile that hatchery-reared salmon might use to differentiate between target return locations and other potential spawning grounds. Title: Effects of Current Hatchery Practices on Salmon Odor Recognition and Responses Author: Lemanski, Joseph R. Salmon hatcheries have been utilized throughout the Pacific Northwest for many decades to mitigate losses, supplement natural spawning populations, and to provide tribal, sport and commercial fishing opportunities. Currently, there is substantial debate on their efficacy and the potential threats hatchery-reared salmonids pose to natural populations. These concerns have lead to a large body of scientific investigation. The potential impacts hatchery-reared salmon may have on natural spawning populations can take many forms, such as competition, predation, and genetic introgression. Many of these issues arise from straying of hatchery-reared salmon from target return locations into areas where naturally spawning populations of salmon occur. In my thesis, I considered two questions related to hatchery practices and straying of hatchery-reared salmon. First, I addressed whether exposure to unfamiliar conspecifics during incubation (embryonic development) affects the population recognition responses of emergent steelhead (Oncorhynchus mykiss). I then examined whether dissolved free amino acids (DFAAs, chemicals believed to be important for natal stream identification in salmonids) are significantly altered as water sourced from a river passes through a salmon hatchery. The results of my first study suggested that newly emergent steelhead showed no preference for water conditioned by either familiar (fish from the same population) or unfamiliar (fish from geographically separate population) populations. These results suggest that exposure to unfamiliar or unrelated population specific odors during incubation in a hatchery may not have any significant effects on population recognition responses. The data from my second study suggested that both hatchery and river water DFAA profiles are very similar. I hypothesize that straying observed in hatchery-reared salmon may be due in part to a lack of a unique, distinguishable odor profile that hatchery-reared salmon might use to differentiate between target return locations and other potential spawning grounds. Close

• 85. [Image] Five species of western salmon

  	The first slide illustrates the five species of salmon as follows: a. King Salmon, also Quinnat, Chinook, or Tyee. It is the salmon of highest quality and value. The average weight ranges about 22 pounds, ...
  	Citation × Citation Citation Abstract Copy Title: Five species of western salmon Year: 1925 The first slide illustrates the five species of salmon as follows: a. King Salmon, also Quinnat, Chinook, or Tyee. It is the salmon of highest quality and value. The average weight ranges about 22 pounds, but may reach as high as 70 pounds or even eighty. It is typical of the Columbia River, but is also taken north and south of that stream. b. Red Salmon, or Sockeye. This fish has a place second only to the Chinook, both in quality and commercial value. In weight the average is considerably less than that of the Chinook, but the flesh is bright red and of excellent flavor. This variety is typical of Puget Sound but is taken both north and south of that region. c. Silver Salmon. This is also a splendid food fish. Its flesh varies from pink to red and by many is considered equal in quality to the Red Salmon. The Silver Salmon is typical of the rivers of the state other than the Columbia. During some seasons the Siuslaw, Umpqua and other rivers of the state have large quantities of this species. At such times many car loads of iced salmon are shipped from towns along these rivers. Some are being shipped directly to the Atlantic coast markets. d. "Chum" or "Keta". This variety was called for many years dog salmon and is yet known to many by that name. It was formerly considered a very inferior species and was seldom used either as a fresh product or for canning. The prejudice against it was largely due to the name, and to the pale color of its flesh. The prejudice has been rapidly decreasing since this species has been found to be a really good food fish, and during recent years. It has furnished fully one-fifth of the Pacific coast pack. e. The fifth salmon is known as the Humpback. It is of smaller size than the Dog Salmon, and like the latter is of the white variety, poor food when fresh and of inferior quality when canned. It is little used as a commercial product. Beside these five species of true salmon there is another commonly known as the Steelhead Salmon. It belongs to a different genus from the above mentioned forms but plays a very important part in the fishing industry of the state. It is considered an excellent food fish and is used freely by the canners, often under the name of the true salmon. The Steelhead is really a trout, ascending the rivers to spawn, but returning to the sea again. From a biological point of view, our Pacific Coast salmon are among the most remarkable fishes known; remarkable because so little is known of the fish while in the sea. The greater part of their life is therefore shrouded in mystery. The following facts are, however, well known: Fact 1. That the salmon ascend the rivers to spawn, some species going but a few miles from brackish waters while others travel hundreds of miles from the sea, in fact into the very small streams, pushing as far as fish of this size can swim. Spawning grounds are almost invariably in the cold fresh waters fed from lakes, springs, and mountain snows. Fact 2. During the ascent of the rivers the salmon do not take any food. As a result, their digestive organization becomes shrunken and functionless. Fact 3. The adult salmon after spawning all die. None of them live to get back to the sea. Fact 4. The young hatched in the small streams may in some species make their way down to the sea the same season; in others they remain in fresh water until the next year. Fact 5. A period of years is spent in the ocean, probably from three to five, depending upon the species. During this time practically nothing is known of their habits. Title: Five species of western salmon Year: 1925 The first slide illustrates the five species of salmon as follows: a. King Salmon, also Quinnat, Chinook, or Tyee. It is the salmon of highest quality and value. The average weight ranges about 22 pounds, but may reach as high as 70 pounds or even eighty. It is typical of the Columbia River, but is also taken north and south of that stream. b. Red Salmon, or Sockeye. This fish has a place second only to the Chinook, both in quality and commercial value. In weight the average is considerably less than that of the Chinook, but the flesh is bright red and of excellent flavor. This variety is typical of Puget Sound but is taken both north and south of that region. c. Silver Salmon. This is also a splendid food fish. Its flesh varies from pink to red and by many is considered equal in quality to the Red Salmon. The Silver Salmon is typical of the rivers of the state other than the Columbia. During some seasons the Siuslaw, Umpqua and other rivers of the state have large quantities of this species. At such times many car loads of iced salmon are shipped from towns along these rivers. Some are being shipped directly to the Atlantic coast markets. d. "Chum" or "Keta". This variety was called for many years dog salmon and is yet known to many by that name. It was formerly considered a very inferior species and was seldom used either as a fresh product or for canning. The prejudice against it was largely due to the name, and to the pale color of its flesh. The prejudice has been rapidly decreasing since this species has been found to be a really good food fish, and during recent years. It has furnished fully one-fifth of the Pacific coast pack. e. The fifth salmon is known as the Humpback. It is of smaller size than the Dog Salmon, and like the latter is of the white variety, poor food when fresh and of inferior quality when canned. It is little used as a commercial product. Beside these five species of true salmon there is another commonly known as the Steelhead Salmon. It belongs to a different genus from the above mentioned forms but plays a very important part in the fishing industry of the state. It is considered an excellent food fish and is used freely by the canners, often under the name of the true salmon. The Steelhead is really a trout, ascending the rivers to spawn, but returning to the sea again. From a biological point of view, our Pacific Coast salmon are among the most remarkable fishes known; remarkable because so little is known of the fish while in the sea. The greater part of their life is therefore shrouded in mystery. The following facts are, however, well known: Fact 1. That the salmon ascend the rivers to spawn, some species going but a few miles from brackish waters while others travel hundreds of miles from the sea, in fact into the very small streams, pushing as far as fish of this size can swim. Spawning grounds are almost invariably in the cold fresh waters fed from lakes, springs, and mountain snows. Fact 2. During the ascent of the rivers the salmon do not take any food. As a result, their digestive organization becomes shrunken and functionless. Fact 3. The adult salmon after spawning all die. None of them live to get back to the sea. Fact 4. The young hatched in the small streams may in some species make their way down to the sea the same season; in others they remain in fresh water until the next year. Fact 5. A period of years is spent in the ocean, probably from three to five, depending upon the species. During this time practically nothing is known of their habits. Close

• 86. [Article] Willamette Biological Opinion Hatchery Research 2009 Annual Report

  Abstract -- This report fulfills a requirement under Task Order NWPPM-09-FH-05, covering activities of July 2009–May 2010 that were implemented by ODFW on behalf of the Corps to assist with meeting the ...

  Citation × Citation Citation Abstract Copy Title: Willamette Biological Opinion Hatchery Research 2009 Annual Report Abstract -- This report fulfills a requirement under Task Order NWPPM-09-FH-05, covering activities of July 2009–May 2010 that were implemented by ODFW on behalf of the Corps to assist with meeting the requirements of the reasonable and prudent alternatives (RPAs) and measures prescribed in the Willamette Project Biological Opinion (BiOp) of July 2008 (NOAA 2008). The Corps provided funding to continue ongoing monitoring activities and initiate long-term planning. Primary tasks by species included: Spring Chinook salmon Task 1.1: Determine abundance, distribution, and percent hatchery-origin fish on spawning grounds downstream of federal dams. Task 1.2: Monitor clipped & unclipped fish passing Leaburg and Upper Bennett dams. Task 2.1: Collection, spawn timing, and hatchery/wild composition for broodstock management. Task 2.2: Determine survival of outplanted fish (upstream of federal dams) and abundance of spawners. Title: Willamette Biological Opinion Hatchery Research 2009 Annual Report Abstract -- This report fulfills a requirement under Task Order NWPPM-09-FH-05, covering activities of July 2009–May 2010 that were implemented by ODFW on behalf of the Corps to assist with meeting the requirements of the reasonable and prudent alternatives (RPAs) and measures prescribed in the Willamette Project Biological Opinion (BiOp) of July 2008 (NOAA 2008). The Corps provided funding to continue ongoing monitoring activities and initiate long-term planning. Primary tasks by species included: Spring Chinook salmon Task 1.1: Determine abundance, distribution, and percent hatchery-origin fish on spawning grounds downstream of federal dams. Task 1.2: Monitor clipped & unclipped fish passing Leaburg and Upper Bennett dams. Task 2.1: Collection, spawn timing, and hatchery/wild composition for broodstock management. Task 2.2: Determine survival of outplanted fish (upstream of federal dams) and abundance of spawners. Close

• 87. [Article] Systematics, variation, distribution, and biology of lampreys of the genus Lampetra in Oregon

  Based on the number of velar tentacles and the form of longitudinal lingual laminae found in Lampetra (Entosphenus) t. tridentata and its closely related forms, the taxon Entosphenus should not be considered ...

  Citation × Citation Citation Abstract Copy Title: Systematics, variation, distribution, and biology of lampreys of the genus Lampetra in Oregon Author: Kan, Ting Tien Based on the number of velar tentacles and the form of longitudinal lingual laminae found in Lampetra (Entosphenus) t. tridentata and its closely related forms, the taxon Entosphenus should not be considered as a genus as commonly adopted, but, along with the taxa Lethenteron and Lampetra, should be regarded as a subgenus of the genus Lampetra. The genus Lampetra is distinct for various reasons, including particularly the character that no cusps are present in the area distal to the lateral circumorals. Six nominal species, belonging to the subgenera Entosphenus and Lampetra, have been known to occur in four of the seven major drainage systems of Oregon. The anadromous L. (E.) t.tridentata, is widespread in the Columbia River and Coastal drainage systems, occurring in most streams with access to the ocean regardless of distance to the ocean, as long as suitable spawning grounds and ammocoete habitats are present. Morphometrics and dentitional features vary little over its geographical range. The number of trunk myomeres and the adult body size vary appreciably so that two categories of regional forms, coastal and inland, may be recognized. The coastal forms are generally smaller and have fewer trunk myomeres compared to those of the larger inland forms. The spawning migration begins from the late spring to late summer for the coastal forms but may occur much earlier for the inland forms. The adult body size appears to be positively correlated with absolute fecundity, but is negatively correlated with relative fecundity. Duration of the larval period is from four to six years. Metamorphosis usually takes place in the fall. Macrophthalmia are known to enter the ocean over a long period, those descending coastal streams enter salt water in the late fall and early winter, whereas the peak of emigration from inland streams is in the early spring. Duration of its marine parasitic phase appears to be from 20 to 40 months. The small landlocked L. (E.) t. kawiaga n. subsp., found only in the Klamath and Goose Lake drainage systems in southern Oregon and northern California, differs from t. tridentata in body size and various meristic and morphometric characters. Its lacustrine parasitic phase is about 12 months long. L. (E.) lethophaga, the nonparasitic derivative of tridentata, occurs in the Klamath and probably also the Goose Lake drainage system. It is characterized by an extension of the larval phase and by a greatly reduced post-larval period. The presumably extinct L. (E. ) minima, a parasitic derivative of tridentata, found formerly only in Miller Lake, Oregon, possessed a number of characters that were concomitants of dwarfism, the distinctive feature of the species. Relationships and evolution among the subgenus Entosphenus were discussed. Distributional records of L. ayresii and L. richardsoni of the subgenus Lampetra in Oregon were given. Evidence indicates that a complex of clinal races, including L. pacifica Vladykov, 1973, may exist in the latter species. Title: Systematics, variation, distribution, and biology of lampreys of the genus Lampetra in Oregon Author: Kan, Ting Tien Based on the number of velar tentacles and the form of longitudinal lingual laminae found in Lampetra (Entosphenus) t. tridentata and its closely related forms, the taxon Entosphenus should not be considered as a genus as commonly adopted, but, along with the taxa Lethenteron and Lampetra, should be regarded as a subgenus of the genus Lampetra. The genus Lampetra is distinct for various reasons, including particularly the character that no cusps are present in the area distal to the lateral circumorals. Six nominal species, belonging to the subgenera Entosphenus and Lampetra, have been known to occur in four of the seven major drainage systems of Oregon. The anadromous L. (E.) t.tridentata, is widespread in the Columbia River and Coastal drainage systems, occurring in most streams with access to the ocean regardless of distance to the ocean, as long as suitable spawning grounds and ammocoete habitats are present. Morphometrics and dentitional features vary little over its geographical range. The number of trunk myomeres and the adult body size vary appreciably so that two categories of regional forms, coastal and inland, may be recognized. The coastal forms are generally smaller and have fewer trunk myomeres compared to those of the larger inland forms. The spawning migration begins from the late spring to late summer for the coastal forms but may occur much earlier for the inland forms. The adult body size appears to be positively correlated with absolute fecundity, but is negatively correlated with relative fecundity. Duration of the larval period is from four to six years. Metamorphosis usually takes place in the fall. Macrophthalmia are known to enter the ocean over a long period, those descending coastal streams enter salt water in the late fall and early winter, whereas the peak of emigration from inland streams is in the early spring. Duration of its marine parasitic phase appears to be from 20 to 40 months. The small landlocked L. (E.) t. kawiaga n. subsp., found only in the Klamath and Goose Lake drainage systems in southern Oregon and northern California, differs from t. tridentata in body size and various meristic and morphometric characters. Its lacustrine parasitic phase is about 12 months long. L. (E.) lethophaga, the nonparasitic derivative of tridentata, occurs in the Klamath and probably also the Goose Lake drainage system. It is characterized by an extension of the larval phase and by a greatly reduced post-larval period. The presumably extinct L. (E. ) minima, a parasitic derivative of tridentata, found formerly only in Miller Lake, Oregon, possessed a number of characters that were concomitants of dwarfism, the distinctive feature of the species. Relationships and evolution among the subgenus Entosphenus were discussed. Distributional records of L. ayresii and L. richardsoni of the subgenus Lampetra in Oregon were given. Evidence indicates that a complex of clinal races, including L. pacifica Vladykov, 1973, may exist in the latter species. Close

• 88. [Article] Tuberculosis in Pacific salmon and steelhead trout

  Tuberculosis in salmonoid fishes was first observed in the 1952 run of fall chinook salmon (Oncorhynchus tshawytscha) returning to the Bonneville Hatchery of the Oregon Fish Commission. In the studies ...

  Citation × Citation Citation Abstract Copy Title: Tuberculosis in Pacific salmon and steelhead trout Author: Ordal, Erling Josef, 1906-, Oregon. Fish Commission, Wood, James W. Tuberculosis in salmonoid fishes was first observed in the 1952 run of fall chinook salmon (Oncorhynchus tshawytscha) returning to the Bonneville Hatchery of the Oregon Fish Commission. In the studies reported here, tuberculosis was found not only in adult spring chinook but in silver salmon (0. kisutch), blueback salmon (0. nerka), and in anadromous and resident strains of rainbow trout (Salmo gairdnerii). Advanced tuberculosis was found in salmonoid fishes held in fresh water for two years or longer, as well as in adults returning from the sea. Lesions were most frequently observed in the liver, and varied in size from small miliary tubercles to huge necrotic areas, filled with characteristic acid-fast bacilli. The typical bacilli were found in stained smears from the kidney, heart, musculature, brain, intestines, pyloric caeca, and roe of infected fish. The disease was originally observed in sexually-underdeveloped fish, and there is indication that it interferes with sexual maturation. It was found that tuberculosis in marked salmon known to be of hatchery origin was extremely high - in some cases 100 percent. Tuberculosis was absent in the small number of silver and chum salmon examined which were known to be the progeny from natural spawning. It is suggested that dissemination of the disease may be due to fish-cultural practices such as the feeding of untreated carcasses and the viscera from tuberculous fish. Since acid-fast bacilli were found in the roe of some fish, it is also suggested that the disease may be transmitted to healthy eggs during the process of fertilization. Tuberculous adult spring chinook were found less capable of surviving to maturity after they reached the spawning grounds than were non-infected fish. It is likely that tuberculosis also influences the ability of salmon to survive during earlier stages of their life history. The incidence of tuberculosis in adult spring chinook entering the Dexter holding ponds on the Middle Fork of the Willamette River in 1955 and 1956 was 8.7 and 6.1 percent, respectively. The increase in incidence to 58.8 percent in 1957 is attributed to the increased dependency of the run on artificial propagation necessitated by the construction of Lookout Point Dam. Among chinook caught in the Columbia River gill-net fishery in. February and in May 1956, 12.3 and 10.5 percent, respectively, of those examined were tuberculous. Although these are spring chinook, it is believed that hatchery reared fall chinook also entered the catch, especially during May, and may have contributed to the number of tuberculous fish taken. Title: Tuberculosis in Pacific salmon and steelhead trout Author: Ordal, Erling Josef, 1906-, Oregon. Fish Commission, Wood, James W. Tuberculosis in salmonoid fishes was first observed in the 1952 run of fall chinook salmon (Oncorhynchus tshawytscha) returning to the Bonneville Hatchery of the Oregon Fish Commission. In the studies reported here, tuberculosis was found not only in adult spring chinook but in silver salmon (0. kisutch), blueback salmon (0. nerka), and in anadromous and resident strains of rainbow trout (Salmo gairdnerii). Advanced tuberculosis was found in salmonoid fishes held in fresh water for two years or longer, as well as in adults returning from the sea. Lesions were most frequently observed in the liver, and varied in size from small miliary tubercles to huge necrotic areas, filled with characteristic acid-fast bacilli. The typical bacilli were found in stained smears from the kidney, heart, musculature, brain, intestines, pyloric caeca, and roe of infected fish. The disease was originally observed in sexually-underdeveloped fish, and there is indication that it interferes with sexual maturation. It was found that tuberculosis in marked salmon known to be of hatchery origin was extremely high - in some cases 100 percent. Tuberculosis was absent in the small number of silver and chum salmon examined which were known to be the progeny from natural spawning. It is suggested that dissemination of the disease may be due to fish-cultural practices such as the feeding of untreated carcasses and the viscera from tuberculous fish. Since acid-fast bacilli were found in the roe of some fish, it is also suggested that the disease may be transmitted to healthy eggs during the process of fertilization. Tuberculous adult spring chinook were found less capable of surviving to maturity after they reached the spawning grounds than were non-infected fish. It is likely that tuberculosis also influences the ability of salmon to survive during earlier stages of their life history. The incidence of tuberculosis in adult spring chinook entering the Dexter holding ponds on the Middle Fork of the Willamette River in 1955 and 1956 was 8.7 and 6.1 percent, respectively. The increase in incidence to 58.8 percent in 1957 is attributed to the increased dependency of the run on artificial propagation necessitated by the construction of Lookout Point Dam. Among chinook caught in the Columbia River gill-net fishery in. February and in May 1956, 12.3 and 10.5 percent, respectively, of those examined were tuberculous. Although these are spring chinook, it is believed that hatchery reared fall chinook also entered the catch, especially during May, and may have contributed to the number of tuberculous fish taken. Close

• 89. [Article] Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska

  Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater ...

  Citation × Citation Citation Abstract Copy Title: Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska Author: Neilson, Brian J. Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater and marine habitats including lacustrine, riverine, estuarine, and marine. Forty-five whitefish were tagged with radio transmitters in 2006 and 2007, and another 29 whitefish were tagged with acoustic tags in 2008. In addition, otolith chemistry was used to evaluate marine habitat use of humpback whitefish sampled from McKinley Lake in the Copper River Delta, Alaska. Movements and migration of tagged fish were tracked using biotelemetry techniques from boats, airplanes, and fixed receiver stations throughout the spring, summer, and fall. Sagittal otoliths were extracted from 20 humpback whitefish and a chemical analysis was performed to evaluate levels of Sr:Ca. Biotelemetry and sampling results revealed seasonal migrations where humpback whitefish migrated into McKinley Lake in mid to late spring and left the lake by late summer and early fall. Fish migrated to the Copper River in the fall by traveling down Alaganik Slough and then to the Copper River by traveling through Pete Dahl Cutoff Slough or the Gulf of Alaska. Fish travel up the Copper River presumably to their spawning grounds. Nine tagged fish returned to McKinley Lake in 2007 and four tagged fish in 2008, indicating some fidelity to the summer feeding site. Otolith chemistry detected marine migrations in 45% of the samples. Three migratory behaviors were observed, while some individuals inhabited only freshwater environments, some individuals made single migrations to marine habitats, and other individuals made multiple migrations to marine habitats. Age of whitefish ranged from 2 to 9 years. Analysis of small-scale movement of humpback whitefish in McKinley Lake found movement rates to be significantly higher at dusk compared to night in one sampling period. However, diel movement activity in all other diel periods did not significantly differ, suggesting arrhythmic diel movement. A large portion of the lake was occupied at any given time, but not all areas were used equally. Activity levels, measured by change in zones, were variable between dates and indicated that fish often moved between detection zones. An increase in activity was observed in individuals 48 h prior to migration from the lake. This study provides the first documentation of migration, movement, and habitat use of humpback whitefish in the Copper River Delta, Alaska. Results of this study will help inform management of humpback whitefish in order to sustain populations into the future. This information should be considered in land use and species management planning in the Copper River basin including fish passage and harvest regulations. Title: Migration, movement, and habitat use of humpback whitefish (Coregonus pidschian) in the Copper River Delta, Alaska Author: Neilson, Brian J. Research conducted on humpback whitefish Coregonus pidschian in the Copper River Delta, Alaska has revealed a complex life history involving seasonal migrations and the occupation of a variety of freshwater and marine habitats including lacustrine, riverine, estuarine, and marine. Forty-five whitefish were tagged with radio transmitters in 2006 and 2007, and another 29 whitefish were tagged with acoustic tags in 2008. In addition, otolith chemistry was used to evaluate marine habitat use of humpback whitefish sampled from McKinley Lake in the Copper River Delta, Alaska. Movements and migration of tagged fish were tracked using biotelemetry techniques from boats, airplanes, and fixed receiver stations throughout the spring, summer, and fall. Sagittal otoliths were extracted from 20 humpback whitefish and a chemical analysis was performed to evaluate levels of Sr:Ca. Biotelemetry and sampling results revealed seasonal migrations where humpback whitefish migrated into McKinley Lake in mid to late spring and left the lake by late summer and early fall. Fish migrated to the Copper River in the fall by traveling down Alaganik Slough and then to the Copper River by traveling through Pete Dahl Cutoff Slough or the Gulf of Alaska. Fish travel up the Copper River presumably to their spawning grounds. Nine tagged fish returned to McKinley Lake in 2007 and four tagged fish in 2008, indicating some fidelity to the summer feeding site. Otolith chemistry detected marine migrations in 45% of the samples. Three migratory behaviors were observed, while some individuals inhabited only freshwater environments, some individuals made single migrations to marine habitats, and other individuals made multiple migrations to marine habitats. Age of whitefish ranged from 2 to 9 years. Analysis of small-scale movement of humpback whitefish in McKinley Lake found movement rates to be significantly higher at dusk compared to night in one sampling period. However, diel movement activity in all other diel periods did not significantly differ, suggesting arrhythmic diel movement. A large portion of the lake was occupied at any given time, but not all areas were used equally. Activity levels, measured by change in zones, were variable between dates and indicated that fish often moved between detection zones. An increase in activity was observed in individuals 48 h prior to migration from the lake. This study provides the first documentation of migration, movement, and habitat use of humpback whitefish in the Copper River Delta, Alaska. Results of this study will help inform management of humpback whitefish in order to sustain populations into the future. This information should be considered in land use and species management planning in the Copper River basin including fish passage and harvest regulations. Close

• 90. [Article] Monitoring river restoration using fiber optic temperature measurements in a modeling framework

  The Middle Fork of the John Day River (MFJD) in Northeastern Oregon contains important spawning grounds for spring Chinook and summer steelhead of the Columbia River Basin. In the summer of 2008 phase ...

  Citation × Citation Citation Abstract Copy Title: Monitoring river restoration using fiber optic temperature measurements in a modeling framework Author: Huff, Julie A. The Middle Fork of the John Day River (MFJD) in Northeastern Oregon contains important spawning grounds for spring Chinook and summer steelhead of the Columbia River Basin. In the summer of 2008 phase one of a river restoration project was completed which included the addition of engineered log jams (ELJs) and scour pools. The restoration focuses on increasing habitat diversity and decreasing peak summer temperatures which, perhaps, had been degraded due to anthropogenic activities such as dredge mining, cattle grazing, channelization and deforestation. This study utilized Distributed Temperature Sensing (DTS) technology to measure the temperature the MFJD study site before and after restoration during the summer of 2008. The temperature data along with other physical and climatic data were modeled using a physically based stream temperature model which incorporated groundwater inflows and an average depth of hyporheic exchange over the entire study reach. The root mean square errors for the pre- and post-restoration model are 0.57°C and 0.47°C, respectively. An average depth of the thermal mass associated with hyporheic exchange was calculated within the model to be 11m for pre- restoration and 1.6m for post-restoration. It is unclear as to whether the hyporheic exchange increased due to restoration or is an artifact of high flows during the pre-restoration period. A statistical analysis was completed on the longitudinal temperature profiles of the MFJD to identify lengths of the river whose temperatures are different upstream and downstream. Groundwater inflow was defined as locations with cooler day time and night time temperatures than the surroundings whereas hyporheic discharge was defined as locations with cooler day time temperatures but warmer night time temperature than the surroundings. Statistically significant locations were highlighted for both pre- and post-restoration and equated to an average decrease in local temperature of 0.08°C pre-restoration and 1.18°C post-restoration. This equates to 0.004 m³/s and 0.012 m³/s of groundwater inflow for pre- and post-restoration, respectively. Again, these differences could be artifacts of high flows during pre-restoration and cannot conclusively be linked to the restoration efforts. However, the largest groundwater inflow (0.004 m³/s) can be associated with one ELJ structure and its corresponding scour pool. Title: Monitoring river restoration using fiber optic temperature measurements in a modeling framework Author: Huff, Julie A. The Middle Fork of the John Day River (MFJD) in Northeastern Oregon contains important spawning grounds for spring Chinook and summer steelhead of the Columbia River Basin. In the summer of 2008 phase one of a river restoration project was completed which included the addition of engineered log jams (ELJs) and scour pools. The restoration focuses on increasing habitat diversity and decreasing peak summer temperatures which, perhaps, had been degraded due to anthropogenic activities such as dredge mining, cattle grazing, channelization and deforestation. This study utilized Distributed Temperature Sensing (DTS) technology to measure the temperature the MFJD study site before and after restoration during the summer of 2008. The temperature data along with other physical and climatic data were modeled using a physically based stream temperature model which incorporated groundwater inflows and an average depth of hyporheic exchange over the entire study reach. The root mean square errors for the pre- and post-restoration model are 0.57°C and 0.47°C, respectively. An average depth of the thermal mass associated with hyporheic exchange was calculated within the model to be 11m for pre- restoration and 1.6m for post-restoration. It is unclear as to whether the hyporheic exchange increased due to restoration or is an artifact of high flows during the pre-restoration period. A statistical analysis was completed on the longitudinal temperature profiles of the MFJD to identify lengths of the river whose temperatures are different upstream and downstream. Groundwater inflow was defined as locations with cooler day time and night time temperatures than the surroundings whereas hyporheic discharge was defined as locations with cooler day time temperatures but warmer night time temperature than the surroundings. Statistically significant locations were highlighted for both pre- and post-restoration and equated to an average decrease in local temperature of 0.08°C pre-restoration and 1.18°C post-restoration. This equates to 0.004 m³/s and 0.012 m³/s of groundwater inflow for pre- and post-restoration, respectively. Again, these differences could be artifacts of high flows during pre-restoration and cannot conclusively be linked to the restoration efforts. However, the largest groundwater inflow (0.004 m³/s) can be associated with one ELJ structure and its corresponding scour pool. Close

• 91. [Article] Willamette Biological Opinion Hatchery Research 2010 Annual Report

  Abstract -- Task 1.1: Distribution, Abundance, and Proportion of Hatchery and Natural-Origin Chinook Salmon: Counts of spring Chinook redds were similar in 2010 compared to the 2002–2009 averages for the ...

  Citation × Citation Citation Abstract Copy Title: Willamette Biological Opinion Hatchery Research 2010 Annual Report Abstract -- Task 1.1: Distribution, Abundance, and Proportion of Hatchery and Natural-Origin Chinook Salmon: Counts of spring Chinook redds were similar in 2010 compared to the 2002–2009 averages for the Middle Fork Willamette, McKenzie and the North Santiam rivers and significantly higher in the South Santiam River Preliminary analyses indicate that the proportions of hatchery fish recovered as carcasses from the spawning grounds varied significantly among all four surveyed sub-basins (South Santiam > M. Fork Willamette > North Santiam > McKenzie) Task 1.2: Monitor fin-clipped & unclipped fish passing Leaburg and Upper Bennett dams. Adult fish passage at Leaburg and Upper Bennett dams was continuously monitored in 2010. We estimated that 2,696 spring Chinook (52% unclipped) passed above Leaburg Dam and 5,956 passed above upper Bennett Dam (14% unclipped). Passage at Leaburg Dam of fin-clipped fish was strongly bimodal with peaks in June (coincident with passage of the majority of unclipped fish) and September (coincident with a smaller proportion of unclipped fish). This bimodal peak suggests that hatchery fish might be removed in September to reduce the proportion of hatchery origin spawners while simultaneously reducing the impacts of handling wild fish. Task 2.1: Collection, spawn timing, and Hatchery/Wild (H/W ) composition for broodstock management. Collection, spawn timing, and H/W composition for broodstock management were successfully monitored at all facilities in 2010. Task 2.2: Determine Survival of Outplanted Fish and Abundance of Spawners. Patterns of pre-spawning mortality were similar to results in 2009 with mortality below project dams significantly higher than that above project dams. We did not detect significant differences in mortality between clipped and unclipped spring Chinook. In comparisons of pre-spawning mortality among sub-basins above project dams, pre-spawning mortality was uniformly low in the Breitenbush and N. Santiam above Detroit, S. Santiam above Foster, and in the S. Fork McKenzie. Pre-spawning mortality was uniformly higher above project dams in the N. Fork Mid. Fork Willamette, Fall Creek and the Little N. Fork Santiam. No comprehensive surveys were conducted in the Middle Fork Willamette. Task 3.1: Determine the extent of summer steelhead reproduction in the wild: We developed a formal study plan to analyze and interpret genetic results from a collection of 299 tissue samples from unclipped juvenile steelhead at Willamette Falls, five from the mainstem Willamette River, and two from the South Santiam River in 2010 in addition to a single sample from an unclipped adult steelhead at the Minto fish collection facility. Samples were preserved 7 and cataloged and then shipped to the NOAA Fisheries Manchester, Washington (WA) laboratory for analysis. Task 3.2: Evaluate release strategies for summer steelhead to increase migration and reduce impacts on wild fish. Study plans to evaluate advantages and disadvantages of volitional release strategies were completed and presented in the 2009 annual report to USACE (Cannon et al. 2010). Funding to process the tissue samples was not available in 2010, and no progress was made in executing the proposed work. Title: Willamette Biological Opinion Hatchery Research 2010 Annual Report Abstract -- Task 1.1: Distribution, Abundance, and Proportion of Hatchery and Natural-Origin Chinook Salmon: Counts of spring Chinook redds were similar in 2010 compared to the 2002–2009 averages for the Middle Fork Willamette, McKenzie and the North Santiam rivers and significantly higher in the South Santiam River Preliminary analyses indicate that the proportions of hatchery fish recovered as carcasses from the spawning grounds varied significantly among all four surveyed sub-basins (South Santiam > M. Fork Willamette > North Santiam > McKenzie) Task 1.2: Monitor fin-clipped & unclipped fish passing Leaburg and Upper Bennett dams. Adult fish passage at Leaburg and Upper Bennett dams was continuously monitored in 2010. We estimated that 2,696 spring Chinook (52% unclipped) passed above Leaburg Dam and 5,956 passed above upper Bennett Dam (14% unclipped). Passage at Leaburg Dam of fin-clipped fish was strongly bimodal with peaks in June (coincident with passage of the majority of unclipped fish) and September (coincident with a smaller proportion of unclipped fish). This bimodal peak suggests that hatchery fish might be removed in September to reduce the proportion of hatchery origin spawners while simultaneously reducing the impacts of handling wild fish. Task 2.1: Collection, spawn timing, and Hatchery/Wild (H/W ) composition for broodstock management. Collection, spawn timing, and H/W composition for broodstock management were successfully monitored at all facilities in 2010. Task 2.2: Determine Survival of Outplanted Fish and Abundance of Spawners. Patterns of pre-spawning mortality were similar to results in 2009 with mortality below project dams significantly higher than that above project dams. We did not detect significant differences in mortality between clipped and unclipped spring Chinook. In comparisons of pre-spawning mortality among sub-basins above project dams, pre-spawning mortality was uniformly low in the Breitenbush and N. Santiam above Detroit, S. Santiam above Foster, and in the S. Fork McKenzie. Pre-spawning mortality was uniformly higher above project dams in the N. Fork Mid. Fork Willamette, Fall Creek and the Little N. Fork Santiam. No comprehensive surveys were conducted in the Middle Fork Willamette. Task 3.1: Determine the extent of summer steelhead reproduction in the wild: We developed a formal study plan to analyze and interpret genetic results from a collection of 299 tissue samples from unclipped juvenile steelhead at Willamette Falls, five from the mainstem Willamette River, and two from the South Santiam River in 2010 in addition to a single sample from an unclipped adult steelhead at the Minto fish collection facility. Samples were preserved 7 and cataloged and then shipped to the NOAA Fisheries Manchester, Washington (WA) laboratory for analysis. Task 3.2: Evaluate release strategies for summer steelhead to increase migration and reduce impacts on wild fish. Study plans to evaluate advantages and disadvantages of volitional release strategies were completed and presented in the 2009 annual report to USACE (Cannon et al. 2010). Funding to process the tissue samples was not available in 2010, and no progress was made in executing the proposed work. Close

• 92. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2005 Annual Progress Report

  Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2005. Also summarized are adult broodstock monitoring ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2005 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2005. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, smolt-to-adult survival rate, and successful spawning in nature by hatcheryreared adults, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2003 brood year of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics of adult Chinook salmon in the 2005 return year, and the collection of eggs for the 2005 brood year. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2005 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2005. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, smolt-to-adult survival rate, and successful spawning in nature by hatcheryreared adults, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2003 brood year of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics of adult Chinook salmon in the 2005 return year, and the collection of eggs for the 2005 brood year. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 93. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2006 Annual Progress Report

  Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2006. Also summarized are adult broodstock monitoring ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2006 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2006. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, smolt-to-adult survival rate, and successful spawning in nature by hatcheryreared adults, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2004 brood year of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics of adult Chinook salmon in the 2006 return year, and the collection of eggs for the 2006 brood year. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2006 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2006. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize egg-to-smolt survival rate, smolt quality, smolt-to-adult survival rate, and successful spawning in nature by hatcheryreared adults, as well as to provide information to adapt the programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2004 brood year of juvenile Chinook salmon smolts, the collection, spawning, and adult characteristics of adult Chinook salmon in the 2006 return year, and the collection of eggs for the 2006 brood year. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 94. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2007 Annual Progress Report

  Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2007. Also summarized are adult broodstock monitoring ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2007 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2007. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize eggto-smolt survival rate, smolt quality, smolt-to-adult survival rate, successful spawning in nature by hatchery-reared adults, and to provide information to adapt programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2005 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2007 brood year, Chinook spawning in nature, adult characteristics of adult Chinook salmon in the 2007 return year, and Bacterial Kidney Disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2007 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data for the Lower Snake River Compensation Plan (LSRCP) facilities in 2007. Also summarized are adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers the Nez Perce Tribe (NPT) and the Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. These data are used to design culture practices to optimize eggto-smolt survival rate, smolt quality, smolt-to-adult survival rate, successful spawning in nature by hatchery-reared adults, and to provide information to adapt programs to most effectively meet management objectives. This report provides information on rearing and release operations for the 2005 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2007 brood year, Chinook spawning in nature, adult characteristics of adult Chinook salmon in the 2007 return year, and Bacterial Kidney Disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 95. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2008 Annual Progress Report

  Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2008. Also summarized are the ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2008 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2008. Also summarized are the associated adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers, Nez Perce Tribe (NPT) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. Our co-managers, CTUIR and NPT, have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River, that are discussed and evaluated in reports prepared by each co-management agency. Overall, these data are used to modify culture practices as needed in order to optimize the egg-to-smolt survival, smolt quality, smolt-to-adult survival rate, and to track spawning in nature by hatchery-reared adults. This report provides information on rearing and release operations for the 2006 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2008 brood year, Chinook spawning in nature, numbers and characteristics of adult Chinook salmon in the 2008 return year, recruit summary and age composition of the 2003 brood year, and bacterial kidney disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2008 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2008. Also summarized are the associated adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers, Nez Perce Tribe (NPT) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. Our co-managers, CTUIR and NPT, have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River, that are discussed and evaluated in reports prepared by each co-management agency. Overall, these data are used to modify culture practices as needed in order to optimize the egg-to-smolt survival, smolt quality, smolt-to-adult survival rate, and to track spawning in nature by hatchery-reared adults. This report provides information on rearing and release operations for the 2006 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2008 brood year, Chinook spawning in nature, numbers and characteristics of adult Chinook salmon in the 2008 return year, recruit summary and age composition of the 2003 brood year, and bacterial kidney disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 96. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2009 Annual Progress Report

  Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2009. Also summarized are the ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2009 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2009. Also summarized are the associated adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers, the Nez Perce Tribe (NPT) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. Our co-managers, CTUIR and NPT, have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River, that are discussed and evaluated in reports prepared by each co-management agency. Overall, these data are used to modify culture practices, as needed, in order to optimize the egg-to-smolt survival, smolt quality, and smolt-toadult survival rate, and track spawning in nature by hatchery-reared adults. This report provides information on rearing and release operations for the 2007 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2009 brood year, numbers and characteristics of adult Chinook salmon in the 2009 return year, spawning at Lookingglass Fish Hatchery and in nature, recruit summary and age composition of the 2004 brood year, and bacterial kidney disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2009 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2009. Also summarized are the associated adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers, the Nez Perce Tribe (NPT) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins. Our co-managers, CTUIR and NPT, have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River, that are discussed and evaluated in reports prepared by each co-management agency. Overall, these data are used to modify culture practices, as needed, in order to optimize the egg-to-smolt survival, smolt quality, and smolt-toadult survival rate, and track spawning in nature by hatchery-reared adults. This report provides information on rearing and release operations for the 2007 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2009 brood year, numbers and characteristics of adult Chinook salmon in the 2009 return year, spawning at Lookingglass Fish Hatchery and in nature, recruit summary and age composition of the 2004 brood year, and bacterial kidney disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 97. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2010 Annual Progress Report

  Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2010. Also summarized are the ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2010 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2010. Also summarized are the associated adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers, the Nez Perce Tribe (NPT) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins (Our co-managers, CTUIR and NPT, have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River, that are discussed and evaluated in reports prepared by each co-management agency). Overall, these data are used to modify culture practices, as needed, in order to optimize egg-to-smolt survival, smolt quality, and smolt-to-adult survival rate, and track spawning in nature by hatchery-reared adults. This report provides information on rearing and release operations for the 2008 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2010 brood year, numbers and characteristics of adult Chinook salmon in the 2010 return year, the 2010 spawning year at Lookingglass Fish Hatchery and in nature, recruit summary and age composition of the 2005 brood year, and bacterial kidney disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2010 Annual Progress Report Abstract -- This annual progress report summarizes spring Chinook salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2010. Also summarized are the associated adult broodstock monitoring data collected in the Grande Ronde Basin by our co-managers, the Nez Perce Tribe (NPT) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR). The main objectives of this report are to document and evaluate spring Chinook salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins (Our co-managers, CTUIR and NPT, have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River, that are discussed and evaluated in reports prepared by each co-management agency). Overall, these data are used to modify culture practices, as needed, in order to optimize egg-to-smolt survival, smolt quality, and smolt-to-adult survival rate, and track spawning in nature by hatchery-reared adults. This report provides information on rearing and release operations for the 2008 brood year of juvenile Chinook salmon smolts, the collection of eggs for the 2010 brood year, numbers and characteristics of adult Chinook salmon in the 2010 return year, the 2010 spawning year at Lookingglass Fish Hatchery and in nature, recruit summary and age composition of the 2005 brood year, and bacterial kidney disease (BKD) monitoring. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 98. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2015 Annual Progress Report

  Abstract -- This annual progress report summarizes spring-summer Chinook Salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2015. Also summarized ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2015 Annual Progress Report Abstract -- This annual progress report summarizes spring-summer Chinook Salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2015. Also summarized are the associated broodstock monitoring data collected at weirs in the Grande Ronde Basin that are operated by our co-managers, the Nez Perce Tribe (NPT; Lostine River) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR; Catherine Creek and Upper Grande Ronde River). The main objectives of this report are to document and evaluate spring-sumer Chinook Salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins (CTUIR and NPT have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River that are discussed and evaluated in separate reports prepared by each co-management agency). Overall, these data are used to adaptively manage salmon culture practices in order to optimize egg-to-smolt survival rate, smolt quality, smolt-toadult survival rate, the recruits-per-spawner (R:S) ratio, and to monitor spawning in nature by hatchery-reared salmon. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2015 Annual Progress Report Abstract -- This annual progress report summarizes spring-summer Chinook Salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2015. Also summarized are the associated broodstock monitoring data collected at weirs in the Grande Ronde Basin that are operated by our co-managers, the Nez Perce Tribe (NPT; Lostine River) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR; Catherine Creek and Upper Grande Ronde River). The main objectives of this report are to document and evaluate spring-sumer Chinook Salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins (CTUIR and NPT have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River that are discussed and evaluated in separate reports prepared by each co-management agency). Overall, these data are used to adaptively manage salmon culture practices in order to optimize egg-to-smolt survival rate, smolt quality, smolt-toadult survival rate, the recruits-per-spawner (R:S) ratio, and to monitor spawning in nature by hatchery-reared salmon. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 99. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2016 Annual Progress Report

  Abstract -- This annual progress report summarizes spring-summer Chinook Salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2015. Also summarized ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2016 Annual Progress Report Abstract -- This annual progress report summarizes spring-summer Chinook Salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2015. Also summarized are the associated broodstock monitoring data collected at weirs in the Grande Ronde Basin that are operated by our co-managers, the Nez Perce Tribe (NPT; Lostine River) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR; Catherine Creek and Upper Grande Ronde River). The main objectives of this report are to document and evaluate spring-sumer Chinook Salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins (CTUIR and NPT have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River that are discussed and evaluated in separate reports prepared by each co-management agency). Overall, these data are used to adaptively manage salmon culture practices in order to optimize egg-to-smolt survival rate, smolt quality, smolt-toadult survival rate, the recruits-per-spawner (R:S) ratio, and to monitor spawning in nature by hatchery-reared salmon. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Evaluation Studies - 2016 Annual Progress Report Abstract -- This annual progress report summarizes spring-summer Chinook Salmon monitoring data collected by ODFW for the Lower Snake River Compensation Plan (LSRCP) facilities in 2015. Also summarized are the associated broodstock monitoring data collected at weirs in the Grande Ronde Basin that are operated by our co-managers, the Nez Perce Tribe (NPT; Lostine River) and Confederated Tribes of the Umatilla Indian Reservation (CTUIR; Catherine Creek and Upper Grande Ronde River). The main objectives of this report are to document and evaluate spring-sumer Chinook Salmon culture performance for hatchery programs and achievement of management objectives in the Imnaha and Grande Ronde river basins (CTUIR and NPT have specific program goals for Chinook returns to Catherine Creek, the Upper Grande Ronde River, Lookingglass Creek, and the Lostine River that are discussed and evaluated in separate reports prepared by each co-management agency). Overall, these data are used to adaptively manage salmon culture practices in order to optimize egg-to-smolt survival rate, smolt quality, smolt-toadult survival rate, the recruits-per-spawner (R:S) ratio, and to monitor spawning in nature by hatchery-reared salmon. Lower Snake River Compensation Plan (LSRCP) ODFW- Eastern Oregon Fish Research (EOFR) Close

• 100. [Article] The physiology ecology and run diversity of adult Pacific lamprey, Entosphenus tridentatus, during the freshwater spawning migration

  Pacific lamprey, Entosphenus tridentatus, have shown recent and rapid declines in abundance. These anadromous fish return to streams where they mature, spawn and die. It has been inferred that Pacific ...

  Citation × Citation Citation Abstract Copy Title: The physiology ecology and run diversity of adult Pacific lamprey, Entosphenus tridentatus, during the freshwater spawning migration Author: Clemens, Benjamin Jacob, 1976- Pacific lamprey, Entosphenus tridentatus, have shown recent and rapid declines in abundance. These anadromous fish return to streams where they mature, spawn and die. It has been inferred that Pacific lamprey enter freshwater and reside for ~ 1 year before spawning. This long exposure to the freshwater environment may affect the plasticity of the maturation process and the migration timing of Pacific lamprey. Diversity in run times and body size has been observed for Pacific lamprey, yet it is unknown if this diversity is induced by the freshwater environment or if it is genetic. My first goal was to describe the maturation and migration characteristics of adult Pacific lamprey during their freshwater migration. My second goal was to use these data to make an estimation of the run diversity in Pacific lamprey. I conducted three complementary studies, in the laboratory and the field, to achieve these goals. I held immature adult lamprey (non-ripe fish that had ceased parasitic feeding in the ocean and had returned to freshwater) in the laboratory at temperatures that mimicked what these fish would experience in the wild, during the summer (mean: 21.8 °C), and another group of lamprey at cooler temperature (mean: 13.6 °C) to compare maturation timing and characteristics. The warm water group of lamprey showed significantly greater proportional decreases in body mass following temperature exposure than fish in the cooler water. All fish exposed to the warm water matured the following spring (8-10 months later) whereas only about half of the fish from the cool water exposure matured. To understand the migration distances and timing of adult Pacific lamprey, I tracked radio-tagged fish throughout the Willamette Basin above Willamette Falls, Oregon, by airplane and recorded their location. Fish migrated primarily during the spring to early summer period before stopping during the remainder of summer, when peak river temperatures (≥ 20°C) occurred. These fish tended to remain stationary through the fall and winter. However, at least a few fish continued to migrate upstream after September. I monitored maturation characteristics of adult Pacific lamprey, over time at Willamette Falls, Oregon and compared these fish with recent migrants collected from the Pacific Ocean as they entered freshwater. The results suggest a unimodal spawn timing between April and June, at water temperatures < 20 °C. Between July and mid-September, as water temperatures peaked at ~ 25 °C, relatively immature fish for both sexes prevailed. Warm summer temperatures coincided with an increase and prevalence of testicular atrophy in males, and I also observed a large die-off of lamprey during this time. The immature fish had maturation stages and phenotypic characteristics similar to recent migrants collected at the mouth of the Klamath River, suggesting that the immature fish at Willamette Falls would spawn the following year, and spawners in any given year may have been recent migrants during the previous year. However there is a temporal overlap in the spring of immature and mature fish, and I found evidence from gonad histology of maturing fish as they entered the river from the ocean, suggesting that a cohort is comprised of recent migrants that spawn within several weeks of entering freshwater, and another cohort is comprised of recent migrants that mature and spawn at least 1 year later. I hypothesize that the recent migrants that would likely spawn shortly after entering freshwater are akin to a winter or "ocean maturing" steelhead, Oncorhynchus mykiss, that optimizes feeding and growth in the open ocean for a few years before entering freshwater to spawn low in the river system shortly afterwards. Alternatively, these lamprey may be similar to coastal cutthroat trout, O. clarki clarki, that feed and grow in the coastal areas of the ocean for a few months before entering freshwater to spawn. There could be other less apparent explanations as well. I also hypothesize that the lamprey that would likely spawn within ~ 1 year of entering freshwater are akin to a "stream maturing" steelhead that foregoes feeding and growth opportunities, enters freshwater during the summer – fall, and accesses spawning grounds to spawn at temperatures that promote evolutionary fitness via successful spawning the following spring. Based on the results of my research, I hypothesize that warm summer temperatures (> 20 °C) can act as a strong selection factor against stream maturing Pacific lamprey in two ways. First, these temperatures may expedite their maturation, while at the same time slowing their migration. If these hypotheses are true, then I predict an uncoupling of spawn timing with optimal habitat characteristics, that would promote fitness, in the upper watershed. Second, summer temperatures may cause gonad atrophy and death prior to spawning. This scenario may select for ocean maturing Pacific lamprey. Title: The physiology ecology and run diversity of adult Pacific lamprey, Entosphenus tridentatus, during the freshwater spawning migration Author: Clemens, Benjamin Jacob, 1976- Pacific lamprey, Entosphenus tridentatus, have shown recent and rapid declines in abundance. These anadromous fish return to streams where they mature, spawn and die. It has been inferred that Pacific lamprey enter freshwater and reside for ~ 1 year before spawning. This long exposure to the freshwater environment may affect the plasticity of the maturation process and the migration timing of Pacific lamprey. Diversity in run times and body size has been observed for Pacific lamprey, yet it is unknown if this diversity is induced by the freshwater environment or if it is genetic. My first goal was to describe the maturation and migration characteristics of adult Pacific lamprey during their freshwater migration. My second goal was to use these data to make an estimation of the run diversity in Pacific lamprey. I conducted three complementary studies, in the laboratory and the field, to achieve these goals. I held immature adult lamprey (non-ripe fish that had ceased parasitic feeding in the ocean and had returned to freshwater) in the laboratory at temperatures that mimicked what these fish would experience in the wild, during the summer (mean: 21.8 °C), and another group of lamprey at cooler temperature (mean: 13.6 °C) to compare maturation timing and characteristics. The warm water group of lamprey showed significantly greater proportional decreases in body mass following temperature exposure than fish in the cooler water. All fish exposed to the warm water matured the following spring (8-10 months later) whereas only about half of the fish from the cool water exposure matured. To understand the migration distances and timing of adult Pacific lamprey, I tracked radio-tagged fish throughout the Willamette Basin above Willamette Falls, Oregon, by airplane and recorded their location. Fish migrated primarily during the spring to early summer period before stopping during the remainder of summer, when peak river temperatures (≥ 20°C) occurred. These fish tended to remain stationary through the fall and winter. However, at least a few fish continued to migrate upstream after September. I monitored maturation characteristics of adult Pacific lamprey, over time at Willamette Falls, Oregon and compared these fish with recent migrants collected from the Pacific Ocean as they entered freshwater. The results suggest a unimodal spawn timing between April and June, at water temperatures < 20 °C. Between July and mid-September, as water temperatures peaked at ~ 25 °C, relatively immature fish for both sexes prevailed. Warm summer temperatures coincided with an increase and prevalence of testicular atrophy in males, and I also observed a large die-off of lamprey during this time. The immature fish had maturation stages and phenotypic characteristics similar to recent migrants collected at the mouth of the Klamath River, suggesting that the immature fish at Willamette Falls would spawn the following year, and spawners in any given year may have been recent migrants during the previous year. However there is a temporal overlap in the spring of immature and mature fish, and I found evidence from gonad histology of maturing fish as they entered the river from the ocean, suggesting that a cohort is comprised of recent migrants that spawn within several weeks of entering freshwater, and another cohort is comprised of recent migrants that mature and spawn at least 1 year later. I hypothesize that the recent migrants that would likely spawn shortly after entering freshwater are akin to a winter or "ocean maturing" steelhead, Oncorhynchus mykiss, that optimizes feeding and growth in the open ocean for a few years before entering freshwater to spawn low in the river system shortly afterwards. Alternatively, these lamprey may be similar to coastal cutthroat trout, O. clarki clarki, that feed and grow in the coastal areas of the ocean for a few months before entering freshwater to spawn. There could be other less apparent explanations as well. I also hypothesize that the lamprey that would likely spawn within ~ 1 year of entering freshwater are akin to a "stream maturing" steelhead that foregoes feeding and growth opportunities, enters freshwater during the summer – fall, and accesses spawning grounds to spawn at temperatures that promote evolutionary fitness via successful spawning the following spring. Based on the results of my research, I hypothesize that warm summer temperatures (> 20 °C) can act as a strong selection factor against stream maturing Pacific lamprey in two ways. First, these temperatures may expedite their maturation, while at the same time slowing their migration. If these hypotheses are true, then I predict an uncoupling of spawn timing with optimal habitat characteristics, that would promote fitness, in the upper watershed. Second, summer temperatures may cause gonad atrophy and death prior to spawning. This scenario may select for ocean maturing Pacific lamprey. Close