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• 1. [Article] The effects on salmon populations of the partial elimination of fixed fishing gear on the Columbia River in 1935

  1. Six major types of commercial gear have been used to take salmon and steelhead on the Columbia River; namely, gill nets, set nets, seines, traps, fish wheels and dip nets. 2. The five important commercial ...

  Citation × Citation Citation Abstract Copy Title: The effects on salmon populations of the partial elimination of fixed fishing gear on the Columbia River in 1935 Author: Johnson, Donald R., Chapman, Wilbert McLeod, 1910-1970, Oregon. Fish Commission, Schoning, Robert W. 1. Six major types of commercial gear have been used to take salmon and steelhead on the Columbia River; namely, gill nets, set nets, seines, traps, fish wheels and dip nets. 2. The five important commercial species in the Columbia River are chinook, silver, blueback and chum salmon and steelhead trout. 3. In 1927 fish wheels were eliminated in Oregon. In 1935 fish wheels, traps, seines and set nets were eliminated in Washington. 4. The effect of the gear change in Washington in 1935 has been to increase the take in other gears, while the previous trend of total landings has not changed appreciably. 5. There is no conclusive evidence that the elimination of fixed gear in Washington increased the escapement of salmon and steelhead. 6. There is no conclusive evidence that any gear is injurious to the run except by subtracting fish from the run. 7. Measures designed to increase the escapement should apply to all gears and cover the entire life history of each species. Title: The effects on salmon populations of the partial elimination of fixed fishing gear on the Columbia River in 1935 Author: Johnson, Donald R., Chapman, Wilbert McLeod, 1910-1970, Oregon. Fish Commission, Schoning, Robert W. 1. Six major types of commercial gear have been used to take salmon and steelhead on the Columbia River; namely, gill nets, set nets, seines, traps, fish wheels and dip nets. 2. The five important commercial species in the Columbia River are chinook, silver, blueback and chum salmon and steelhead trout. 3. In 1927 fish wheels were eliminated in Oregon. In 1935 fish wheels, traps, seines and set nets were eliminated in Washington. 4. The effect of the gear change in Washington in 1935 has been to increase the take in other gears, while the previous trend of total landings has not changed appreciably. 5. There is no conclusive evidence that the elimination of fixed gear in Washington increased the escapement of salmon and steelhead. 6. There is no conclusive evidence that any gear is injurious to the run except by subtracting fish from the run. 7. Measures designed to increase the escapement should apply to all gears and cover the entire life history of each species. Close

• 2. [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

• 3. [Article] A measured delay in the migration of adult chinook salmon at Bonneville Dam on the Columbia River

  A study was undertaken in the fall of 1948 by the Oregon Fish Commission to determine the possible presence and importance of a delay in the migration of adult chinook salmon (Oncorhynchus tshawytscha) ...

  Citation × Citation Citation Abstract Copy Title: A measured delay in the migration of adult chinook salmon at Bonneville Dam on the Columbia River Author: Johnson, Donald R., Oregon. Fish Commission, Schoning, Robert W. A study was undertaken in the fall of 1948 by the Oregon Fish Commission to determine the possible presence and importance of a delay in the migration of adult chinook salmon (Oncorhynchus tshawytscha) at Bonneville Dam on the Columbia River. Approximately 650 chinook were captured, tagged, and released at the Oneonta trap 6.7 miles below Bonneville Dam and 200 were handled similarly at the dam and released above. The tag returns from Celilo Falls, the main commercial fishing area, 60 miles above Bonneville, were compared by location of tagging with regard to date of tagging and the number of days en route. The linear correlation between tagging date and days out was significant for the 39 recoveries tagged at Bonneville but not for the 35 from Oneonta. The later in the season the fish were tagged at Bonneville the more rapidly they migrated to Celilo Falls. With no adjustment for the difference in distance between the two tagging locations, the fish from Oneonta took a significant 3.4 days longer to make the trip to Celilo than the Bonneville tagged fish. When correcting for the distance difference, the delay was reduced to 3.0 or 2.6 days, either of which was still significant. Although the number of recoveries is small, all of those used are believed to be reliable and sufficient for statistical analysis. The study represents only one year's work and investigations of another year may refute or substantiate these findings. Title: A measured delay in the migration of adult chinook salmon at Bonneville Dam on the Columbia River Author: Johnson, Donald R., Oregon. Fish Commission, Schoning, Robert W. A study was undertaken in the fall of 1948 by the Oregon Fish Commission to determine the possible presence and importance of a delay in the migration of adult chinook salmon (Oncorhynchus tshawytscha) at Bonneville Dam on the Columbia River. Approximately 650 chinook were captured, tagged, and released at the Oneonta trap 6.7 miles below Bonneville Dam and 200 were handled similarly at the dam and released above. The tag returns from Celilo Falls, the main commercial fishing area, 60 miles above Bonneville, were compared by location of tagging with regard to date of tagging and the number of days en route. The linear correlation between tagging date and days out was significant for the 39 recoveries tagged at Bonneville but not for the 35 from Oneonta. The later in the season the fish were tagged at Bonneville the more rapidly they migrated to Celilo Falls. With no adjustment for the difference in distance between the two tagging locations, the fish from Oneonta took a significant 3.4 days longer to make the trip to Celilo than the Bonneville tagged fish. When correcting for the distance difference, the delay was reduced to 3.0 or 2.6 days, either of which was still significant. Although the number of recoveries is small, all of those used are believed to be reliable and sufficient for statistical analysis. The study represents only one year's work and investigations of another year may refute or substantiate these findings. Close

• 4. [Article] The future of the Columbia River salmon fisheries

  The salmon runs of the Columbia River constitute one of the most important natural resources of the states of Oregon and Washington. Thousands of people are dependent, wholly or in part, upon these resources ...

  Citation × Citation Citation Abstract Copy Title: The future of the Columbia River salmon fisheries Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 The salmon runs of the Columbia River constitute one of the most important natural resources of the states of Oregon and Washington. Thousands of people are dependent, wholly or in part, upon these resources for their livelihood; and their welfare is dependent upon the maintenance of the salmon runs. It is to the special interest of these people that the salmon supply be maintained at the level of maximum productivity and, indirectly, it is to the interest of all the citizens of these states that this be done. In recent years it has become increasingly evident that these resources, taken as. a whole, are decreasing in productivity and it has been frequently pointed out that this decrease is due primarily to the operation of two factors-- a very intensive fishery and a reduction in spawning and rearing areas due to the utilization of the water resources of the Columbia basin for other purposes. These influences, however, have affected the several species of salmon that are found in the Columbia River quite differently; the more valuable species, Chinooks and bluebacks, showing more evidence of depletion than do the other species, silver salmon, chums and steelhead. Title: The future of the Columbia River salmon fisheries Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 The salmon runs of the Columbia River constitute one of the most important natural resources of the states of Oregon and Washington. Thousands of people are dependent, wholly or in part, upon these resources for their livelihood; and their welfare is dependent upon the maintenance of the salmon runs. It is to the special interest of these people that the salmon supply be maintained at the level of maximum productivity and, indirectly, it is to the interest of all the citizens of these states that this be done. In recent years it has become increasingly evident that these resources, taken as. a whole, are decreasing in productivity and it has been frequently pointed out that this decrease is due primarily to the operation of two factors-- a very intensive fishery and a reduction in spawning and rearing areas due to the utilization of the water resources of the Columbia basin for other purposes. These influences, however, have affected the several species of salmon that are found in the Columbia River quite differently; the more valuable species, Chinooks and bluebacks, showing more evidence of depletion than do the other species, silver salmon, chums and steelhead. Close

• 5. [Article] The salmon runs of the Columbia River in 1938

  Exceptional data are available for the study of the salmon runs of the Columbia River in 1938. Detailed figures on catch were supplied by Oregon and Washington in such form that they could readily be combined ...

  Citation × Citation Citation Abstract Copy Title: The salmon runs of the Columbia River in 1938 Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 Exceptional data are available for the study of the salmon runs of the Columbia River in 1938. Detailed figures on catch were supplied by Oregon and Washington in such form that they could readily be combined with the counts at Bonneville Dam to provide a basis for estimating the escapement. Tables show the catch of each species for each week in each of six zones, and the counts at Bonneville and Rock Island dams. The general course of the run of each species is shown. The numbers of fish bound for the spawning grounds above Rock Island Dam are estimated as follows: Chinook salmon entering Columbia River before May 1, 4 percent; during May, 6 percent; June and July, 15 percent; and August to December, 1 percent. Blueback salmon entering the river during the above periods, 40 percent. Steelhead trout entering the river during June to September, 1 percent; during the rest of the year, 10 percent. Fishing intensities are shown by escapement to catch ratios. Percentages of chinook salmon escapement are less than 15 during May; 17 during June and July; and 33 during the remainder of the year. The June and July runs are now greatly depleted, and an important part of these runs spawns above Rock Island Dam. The blueback salmon escapement is about 20 percent, and of steelhead trout about 33 percent. Weekly and seasonal closed periods are shown to be almost entirely ineffective for increasing the spawning escapement. Exploitation is further increased by the intensive troll fishery conducted from Monterey Bay to southeastern Alaska. Chinook salmon are also subjected to a sport fishery of considerable importance. Main runs of salmon to the Columbia River are practically unprotected and are fished with destructive intensity. Title: The salmon runs of the Columbia River in 1938 Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 Exceptional data are available for the study of the salmon runs of the Columbia River in 1938. Detailed figures on catch were supplied by Oregon and Washington in such form that they could readily be combined with the counts at Bonneville Dam to provide a basis for estimating the escapement. Tables show the catch of each species for each week in each of six zones, and the counts at Bonneville and Rock Island dams. The general course of the run of each species is shown. The numbers of fish bound for the spawning grounds above Rock Island Dam are estimated as follows: Chinook salmon entering Columbia River before May 1, 4 percent; during May, 6 percent; June and July, 15 percent; and August to December, 1 percent. Blueback salmon entering the river during the above periods, 40 percent. Steelhead trout entering the river during June to September, 1 percent; during the rest of the year, 10 percent. Fishing intensities are shown by escapement to catch ratios. Percentages of chinook salmon escapement are less than 15 during May; 17 during June and July; and 33 during the remainder of the year. The June and July runs are now greatly depleted, and an important part of these runs spawns above Rock Island Dam. The blueback salmon escapement is about 20 percent, and of steelhead trout about 33 percent. Weekly and seasonal closed periods are shown to be almost entirely ineffective for increasing the spawning escapement. Exploitation is further increased by the intensive troll fishery conducted from Monterey Bay to southeastern Alaska. Chinook salmon are also subjected to a sport fishery of considerable importance. Main runs of salmon to the Columbia River are practically unprotected and are fished with destructive intensity. Close

• 6. [Article] The Indian Dip Net Fishery at Celilo Falls on the Columbia River

  1. The Indians at Celilo Falls catch an average of over 2,600,000 pounds of fish each year, in dip nets in a manner very much the same as used by their ancestors. 2. The bulk of the fish caught at Celilo ...

  Citation × Citation Citation Abstract Copy Title: The Indian Dip Net Fishery at Celilo Falls on the Columbia River Author: Johnson, Donald R., Oregon. Fish Commission, Merrell, Theodore R., Schoning, Robert W. 1. The Indians at Celilo Falls catch an average of over 2,600,000 pounds of fish each year, in dip nets in a manner very much the same as used by their ancestors. 2. The bulk of the fish caught at Celilo Falls is from the upriver fall run of chinook salmon which spawns in the main Columbia, between Pasco and Rock Island Dam and on the main Snake River between Swan Falls and Marsing. 3. Until the present study, the magnitude of the Indian closed season subsistence catch, averaging 500,000 pounds annually, has been unknown. 4. Most of the fall closed season catch is dried for home use by the Indians during the year although some is sold illegally. 5. The annual average of 50,000 pounds of fish sold directly to tourists is relatively insignificant when compared to the amount sold through regular commercial channels during the open season. 6. The elimination of fixed gear in the Columbia River has increased the percentage of total fish caught by the Indians. In the case of chinooks, the Indian commercial catch increased 8.8 percent. 7. The average annual value of the total Indian catch 1947-1950 is estimated to be $700,000. Title: The Indian Dip Net Fishery at Celilo Falls on the Columbia River Author: Johnson, Donald R., Oregon. Fish Commission, Merrell, Theodore R., Schoning, Robert W. 1. The Indians at Celilo Falls catch an average of over 2,600,000 pounds of fish each year, in dip nets in a manner very much the same as used by their ancestors. 2. The bulk of the fish caught at Celilo Falls is from the upriver fall run of chinook salmon which spawns in the main Columbia, between Pasco and Rock Island Dam and on the main Snake River between Swan Falls and Marsing. 3. Until the present study, the magnitude of the Indian closed season subsistence catch, averaging 500,000 pounds annually, has been unknown. 4. Most of the fall closed season catch is dried for home use by the Indians during the year although some is sold illegally. 5. The annual average of 50,000 pounds of fish sold directly to tourists is relatively insignificant when compared to the amount sold through regular commercial channels during the open season. 6. The elimination of fixed gear in the Columbia River has increased the percentage of total fish caught by the Indians. In the case of chinooks, the Indian commercial catch increased 8.8 percent. 7. The average annual value of the total Indian catch 1947-1950 is estimated to be $700,000. Close

• 7. [Article] Seasonal variations in weight of Columbia River chinook salmon

  A study of the fishery problems raised by the construction of the Grand Coulee Dam on the upper Columbia River was done. Part of the study was to estimate the number of salmon taken in commercial fishery ...

  Citation × Citation Citation Abstract Copy Title: Seasonal variations in weight of Columbia River chinook salmon Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 A study of the fishery problems raised by the construction of the Grand Coulee Dam on the upper Columbia River was done. Part of the study was to estimate the number of salmon taken in commercial fishery for the purpose of comparing this with the number counted as they passed the dam at Bonneville. Title: Seasonal variations in weight of Columbia River chinook salmon Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 A study of the fishery problems raised by the construction of the Grand Coulee Dam on the upper Columbia River was done. Part of the study was to estimate the number of salmon taken in commercial fishery for the purpose of comparing this with the number counted as they passed the dam at Bonneville. Close

• 8. [Article] An application of the control chart method to the analysis of fisheries data

  In a paper now in press as a Bulletin of the U. S. Fish and Wildlife Services the writer has discussed the downward trend of the catch of Columbia River Chinook salmon since 1920 and has stated that the ...

  Citation × Citation Citation Abstract Copy Title: An application of the control chart method to the analysis of fisheries data Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 In a paper now in press as a Bulletin of the U. S. Fish and Wildlife Services the writer has discussed the downward trend of the catch of Columbia River Chinook salmon since 1920 and has stated that the decline is doubtless an indication that the runs of this species are seriously depleted. Recently the same data have been studied by means of the control chart method and the results show so clearly that the productivity has dropped to a new and much lower level that it has seemed worth while to present a brief note amplifying the discussion in the bulletin. Title: An application of the control chart method to the analysis of fisheries data Author: Oregon. Fish Commission, Rich, Willis H. (Willis Horton), 1885-1972 In a paper now in press as a Bulletin of the U. S. Fish and Wildlife Services the writer has discussed the downward trend of the catch of Columbia River Chinook salmon since 1920 and has stated that the decline is doubtless an indication that the runs of this species are seriously depleted. Recently the same data have been studied by means of the control chart method and the results show so clearly that the productivity has dropped to a new and much lower level that it has seemed worth while to present a brief note amplifying the discussion in the bulletin. Close

• 9. [Article] A microcytic anemia of juvenile chinook salmon resulting from diets deficient in vitamin E

  An anemia of juvenile chinook salmon (Oncorhynchus tshawytscha) is described and stages of development separated by recognizable syndromes. A vitamin E-deficient diet of low rancidity produced a severe ...

  Citation × Citation Citation Abstract Copy Title: A microcytic anemia of juvenile chinook salmon resulting from diets deficient in vitamin E Author: Whitmore, Cecil M., Oregon. Fish Commission An anemia of juvenile chinook salmon (Oncorhynchus tshawytscha) is described and stages of development separated by recognizable syndromes. A vitamin E-deficient diet of low rancidity produced a severe microcytic anemia with strong immature red cell response and granulocytosis occurring 2 to 4 weeks before a drop in hemoglobin and hematocrit values. A vitamin E deficiency in association with diets of high rancidity produced a more severe anemia with impaired and delayed blood regeneration, microcytosis, abnormal red cell development, and a pronounced granulocyte response; complete recovery resulted when vitamin E was added to the diet. Title: A microcytic anemia of juvenile chinook salmon resulting from diets deficient in vitamin E Author: Whitmore, Cecil M., Oregon. Fish Commission An anemia of juvenile chinook salmon (Oncorhynchus tshawytscha) is described and stages of development separated by recognizable syndromes. A vitamin E-deficient diet of low rancidity produced a severe microcytic anemia with strong immature red cell response and granulocytosis occurring 2 to 4 weeks before a drop in hemoglobin and hematocrit values. A vitamin E deficiency in association with diets of high rancidity produced a more severe anemia with impaired and delayed blood regeneration, microcytosis, abnormal red cell development, and a pronounced granulocyte response; complete recovery resulted when vitamin E was added to the diet. Close

• 10. [Article] The ocean salmon troll fishery of Oregon

  1. The Oregon troll salmon fishery developed rapidly prior to World War I to reach a peak of between one and three thousand boats fishing off the mouth of the Columbia River during 1919. The fishery later ...

  Citation × Citation Citation Abstract Copy Title: The ocean salmon troll fishery of Oregon Author: Oregon. Fish Commission, Van Hyning, Jack M. 1. The Oregon troll salmon fishery developed rapidly prior to World War I to reach a peak of between one and three thousand boats fishing off the mouth of the Columbia River during 1919. The fishery later expanded to the other coastal areas. There has been a decrease in the number of boats fishing, but a great increase in their efficiency. The development of the tuna fishery resulted in the larger trollers fishing for tuna during the late summer and concentrating on salmon during the spring and early summer. There are about 500 trollers which make Oregon ports their base of operations at the present time. Since 1940 the Oregon troll fishery has landed about 3,000,000 pounds of chinook and silver salmon per year. The troll fishery was practically unregulated until 1948, at which time, preliminary regulations were imposed. 2. Preliminary troll regulations which were imposed since 1948 and altered somewhat in 1949 include a 26 inch minimum size limit and a closed season from November 1 to March 15 on chinook salmon. A closed season for silver salmon extends from November 1 to June 15 to prevent the landing of small silvers during the late spring. 3. This report covers in part the tagging and biological data gathered by the staff of the Oregon Fish Commission during 1946, 1947, 1948 and 1949. 4. There were 506 silvers tagged off Oregon in 1948 and 1949, and 29 (5.7 percent) were recovered. By far the greater percentage were recovered north of their tagging location, indicating a northward migration of silvers in their third and last year to their spawning streams. 5. The recovery of marked silver salmon in the ocean, confirms the findings of the tagging in that early in the season (June) the marked fish were found south of their home streams, and as the season advanced they moved north until during September they were grouped around the mouths of the rivers. 6. The length-weight relationship of troll-caught silver salmon was found to be an exponential type of relationship, and the equation for 1947 is W = 0.23215 x 1.0535 [superscript L]; that for 1948 is W = 0.27952 x 1.04949 [superscript L]. 7. The commercial catch of silver salmon is composed largely of individuals in their third year. There seems to be a considerable difference between the growth rates of different years, but the silvers show an average increase in mean weight from about 4.5 pounds on June first to about eight pounds by November first, dressed weight. They showed an increase in modal length in 1948 from 25.2 inches (total length) in June to 30.4 inches (total length) in November. 8. There were 221 chinook salmon tagged in 1948 and 1949 and eleven recoveries were made. No consistent migration pattern is apparent, but it is apparent that the chinook move both north and south of their natal streams and probably migrate farther than do the silver salmon. 9. The length-weight relationship of the chinook salmon was found to conform to the usual parabolic relationship, W = AL [superscript b]. The equation for 1947 was W = 0.000013126 [superscript L 3.17008] and for 1948, W = 0.000009256 [superscript L 3.24142]. 10. The age and growth of the troll caught chinook salmon was studied. The 2+ group was the dominant year class in the catch of 1919, 1946, and probably 1948, but in 1947 there was slightly more of the 3+ group. The 3+ group was next in abundance in 1919 and 1946, with the 1+ group age class comprising a relatively small part of the catch. There is a considerable variation in the sizes and ages of chinooks found in the different areas at different times, and also between years. 11. During April and May, trolling is concentrated off the mouth of the Columbia River. Usually there is a slight peaking in average weight in the spring, followed by a decline and a subsequent rise to a peak in August. In all cases average weight dropped appreciably after August. 12. The ocean sport fishery operates mainly out of Depoe Bay and Newport, with smaller fleets out of nearly every port on the Oregon Coast. The estimated ocean sport catch in 1949 was 700 chinooks (9,000 pounds) and 9,000 silvers (70,000 pounds). Title: The ocean salmon troll fishery of Oregon Author: Oregon. Fish Commission, Van Hyning, Jack M. 1. The Oregon troll salmon fishery developed rapidly prior to World War I to reach a peak of between one and three thousand boats fishing off the mouth of the Columbia River during 1919. The fishery later expanded to the other coastal areas. There has been a decrease in the number of boats fishing, but a great increase in their efficiency. The development of the tuna fishery resulted in the larger trollers fishing for tuna during the late summer and concentrating on salmon during the spring and early summer. There are about 500 trollers which make Oregon ports their base of operations at the present time. Since 1940 the Oregon troll fishery has landed about 3,000,000 pounds of chinook and silver salmon per year. The troll fishery was practically unregulated until 1948, at which time, preliminary regulations were imposed. 2. Preliminary troll regulations which were imposed since 1948 and altered somewhat in 1949 include a 26 inch minimum size limit and a closed season from November 1 to March 15 on chinook salmon. A closed season for silver salmon extends from November 1 to June 15 to prevent the landing of small silvers during the late spring. 3. This report covers in part the tagging and biological data gathered by the staff of the Oregon Fish Commission during 1946, 1947, 1948 and 1949. 4. There were 506 silvers tagged off Oregon in 1948 and 1949, and 29 (5.7 percent) were recovered. By far the greater percentage were recovered north of their tagging location, indicating a northward migration of silvers in their third and last year to their spawning streams. 5. The recovery of marked silver salmon in the ocean, confirms the findings of the tagging in that early in the season (June) the marked fish were found south of their home streams, and as the season advanced they moved north until during September they were grouped around the mouths of the rivers. 6. The length-weight relationship of troll-caught silver salmon was found to be an exponential type of relationship, and the equation for 1947 is W = 0.23215 x 1.0535 [superscript L]; that for 1948 is W = 0.27952 x 1.04949 [superscript L]. 7. The commercial catch of silver salmon is composed largely of individuals in their third year. There seems to be a considerable difference between the growth rates of different years, but the silvers show an average increase in mean weight from about 4.5 pounds on June first to about eight pounds by November first, dressed weight. They showed an increase in modal length in 1948 from 25.2 inches (total length) in June to 30.4 inches (total length) in November. 8. There were 221 chinook salmon tagged in 1948 and 1949 and eleven recoveries were made. No consistent migration pattern is apparent, but it is apparent that the chinook move both north and south of their natal streams and probably migrate farther than do the silver salmon. 9. The length-weight relationship of the chinook salmon was found to conform to the usual parabolic relationship, W = AL [superscript b]. The equation for 1947 was W = 0.000013126 [superscript L 3.17008] and for 1948, W = 0.000009256 [superscript L 3.24142]. 10. The age and growth of the troll caught chinook salmon was studied. The 2+ group was the dominant year class in the catch of 1919, 1946, and probably 1948, but in 1947 there was slightly more of the 3+ group. The 3+ group was next in abundance in 1919 and 1946, with the 1+ group age class comprising a relatively small part of the catch. There is a considerable variation in the sizes and ages of chinooks found in the different areas at different times, and also between years. 11. During April and May, trolling is concentrated off the mouth of the Columbia River. Usually there is a slight peaking in average weight in the spring, followed by a decline and a subsequent rise to a peak in August. In all cases average weight dropped appreciably after August. 12. The ocean sport fishery operates mainly out of Depoe Bay and Newport, with smaller fleets out of nearly every port on the Oregon Coast. The estimated ocean sport catch in 1949 was 700 chinooks (9,000 pounds) and 9,000 silvers (70,000 pounds). Close