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• 1. [Article] Relationship between spawning behavior of spear squids (Loligo bleekeri) and structures of the port

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Relationship between spawning behavior of spear squids (Loligo bleekeri) and structures of the port Author: Yano, Kenji, Honma, Akihiro, Koganezaki, Kiyoto, Narumi, Hideto, Oka, Sadayuki, Kitahara, Shigeshi Research Paper Title: Relationship between spawning behavior of spear squids (Loligo bleekeri) and structures of the port Author: Yano, Kenji, Honma, Akihiro, Koganezaki, Kiyoto, Narumi, Hideto, Oka, Sadayuki, Kitahara, Shigeshi Research Paper Close

• 2. [Article] The 1951 Alsea River silver salmon tagging program

  During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether ...

  Citation × Citation Citation Abstract Copy Title: The 1951 Alsea River silver salmon tagging program Author: Oregon. Fish Commission, Cleaver, Fred C. (Frederick Charles), 1916-, Morgan, Alfred R. During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether tagged fish released in different apparent conditions suffered differential mortalities. Under the hypothesis that the recovery of the fish in the commercial fishery was independent of the apparent condition of the fish when it was released, a significant value of chi-square was obtained. However, it was concluded that this significance was a result of sampling differences and not actually due to differences in mortality. The number of fish taken in the commercial catch each week was calculated by dividing the number of pounds in the weekly catch by the average weight of the fish in the samples for that week. It was calculated that the commercial fishery took approximately 14,000 fish during the season, which was only about 15 per cent of the run available to the fishery. This is an extremely low fishing mortality and is considerably lower than had been expected. The number of tags taken each week by the commercial fishery was calculated by dividing the number of fish in the catch each week by the number of fish per tag in the samples for the week. It was calculated that 67 tags were taken during the season by the commercial fishery. This number of recoveries was 15.5 per cent of the 438 tags available to the fishery. With the cooperation of a number of boat moorages on the Alsea River, an estimate of the sport catch of silver salmon was made. It was calculated that the lower river sport fishery took approximately 3,000 adult silvers with an additional 500 fish being taken by the bank fishery. The weight of the total catch of 3,500 fish was calculated to be about 33,000 pounds. This weight formed 20.2 percent of the combined commercial and sport catches. It was calculated that 18 tagged fish were taken in the sport catch. A total of 44 numbered Petersen and jaw tags were recovered from both dead and live fish which had reached spawning areas. This number includes three tags recovered from the spawning grounds of adjacent streams. When the tagged fish were examined according to areas recovered, it was found that Drift Creek had a smaller number of fish per tag than any other area with one exception. Recoveries appeared to be distributed throughout the drainage from any particular time of tagging. Fish enter the lower river together, then separate to the various spawning areas in the system. Several fish moved from the tagging location in the Alsea River to adjacent streams. About 7 percent of the total recoveries in Table 12 were made from streams other than the Alsea River. The Petersen and jaw tag recoveries in the samples of the commercial catch were examined for selection of the Petersen tags by the nets. The percentage by size group in the catch of fish with each type of tag was about the same as the percentage by size group with each type of tag at the time of release. Large losses of tags in the fishery would have been reflected by a higher number of fish per tag on the spawning grounds. Since the gill-nets did not appear to be selective on either type of tag, the Petersen tags, jaw tags, and tag scars were combined in the calculations involving tag recoveries. After the fish moved beyond the fishing area, many still did not move rapidly to the spawning grounds. Several were taken in tidewater or in the vicinity of tidewater 48-58 days after they had been tagged. The average time between tagging and recovery on the spawning grounds was 63 days for live fish and 70 days for dead fish. Using the method proposed by Schaefer (1951a) for obtaining a population estimate from spawning ground recoveries, an estimate of the population available to the fishery was made from the number of tags recovered by sampling the commercial catch. It was calculated that approximately 90,000 fish were available to the fishery. About 89,000 fish were calculated to be available to the fishery when the equation N = nt/s was used, where N = the population, n = the sample size, t = the number of fish tagged, and s = the number of tag recoveries. The 95 percent limits of confidence for the population estimate derived from the equation N = nt/s were calculated using the method developed by Chapman (1948). The lower limit was found to be 63,736 fish, and the upper limit was 119,371 fish. Approximately 63,000 of the fish available to the commercial fishery continued the migration to the spawning grounds. Spawning ground tag recoveries provided an estimate of the population in the lower river which was in close agreement with the estimate of the population made from tag recoveries in the commercial fishery. Title: The 1951 Alsea River silver salmon tagging program Author: Oregon. Fish Commission, Cleaver, Fred C. (Frederick Charles), 1916-, Morgan, Alfred R. During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether tagged fish released in different apparent conditions suffered differential mortalities. Under the hypothesis that the recovery of the fish in the commercial fishery was independent of the apparent condition of the fish when it was released, a significant value of chi-square was obtained. However, it was concluded that this significance was a result of sampling differences and not actually due to differences in mortality. The number of fish taken in the commercial catch each week was calculated by dividing the number of pounds in the weekly catch by the average weight of the fish in the samples for that week. It was calculated that the commercial fishery took approximately 14,000 fish during the season, which was only about 15 per cent of the run available to the fishery. This is an extremely low fishing mortality and is considerably lower than had been expected. The number of tags taken each week by the commercial fishery was calculated by dividing the number of fish in the catch each week by the number of fish per tag in the samples for the week. It was calculated that 67 tags were taken during the season by the commercial fishery. This number of recoveries was 15.5 per cent of the 438 tags available to the fishery. With the cooperation of a number of boat moorages on the Alsea River, an estimate of the sport catch of silver salmon was made. It was calculated that the lower river sport fishery took approximately 3,000 adult silvers with an additional 500 fish being taken by the bank fishery. The weight of the total catch of 3,500 fish was calculated to be about 33,000 pounds. This weight formed 20.2 percent of the combined commercial and sport catches. It was calculated that 18 tagged fish were taken in the sport catch. A total of 44 numbered Petersen and jaw tags were recovered from both dead and live fish which had reached spawning areas. This number includes three tags recovered from the spawning grounds of adjacent streams. When the tagged fish were examined according to areas recovered, it was found that Drift Creek had a smaller number of fish per tag than any other area with one exception. Recoveries appeared to be distributed throughout the drainage from any particular time of tagging. Fish enter the lower river together, then separate to the various spawning areas in the system. Several fish moved from the tagging location in the Alsea River to adjacent streams. About 7 percent of the total recoveries in Table 12 were made from streams other than the Alsea River. The Petersen and jaw tag recoveries in the samples of the commercial catch were examined for selection of the Petersen tags by the nets. The percentage by size group in the catch of fish with each type of tag was about the same as the percentage by size group with each type of tag at the time of release. Large losses of tags in the fishery would have been reflected by a higher number of fish per tag on the spawning grounds. Since the gill-nets did not appear to be selective on either type of tag, the Petersen tags, jaw tags, and tag scars were combined in the calculations involving tag recoveries. After the fish moved beyond the fishing area, many still did not move rapidly to the spawning grounds. Several were taken in tidewater or in the vicinity of tidewater 48-58 days after they had been tagged. The average time between tagging and recovery on the spawning grounds was 63 days for live fish and 70 days for dead fish. Using the method proposed by Schaefer (1951a) for obtaining a population estimate from spawning ground recoveries, an estimate of the population available to the fishery was made from the number of tags recovered by sampling the commercial catch. It was calculated that approximately 90,000 fish were available to the fishery. About 89,000 fish were calculated to be available to the fishery when the equation N = nt/s was used, where N = the population, n = the sample size, t = the number of fish tagged, and s = the number of tag recoveries. The 95 percent limits of confidence for the population estimate derived from the equation N = nt/s were calculated using the method developed by Chapman (1948). The lower limit was found to be 63,736 fish, and the upper limit was 119,371 fish. Approximately 63,000 of the fish available to the commercial fishery continued the migration to the spawning grounds. Spawning ground tag recoveries provided an estimate of the population in the lower river which was in close agreement with the estimate of the population made from tag recoveries in the commercial fishery. Close

• 3. [Article] Three-year Closure of Sailfin sandfish, Arctoscopus japonicus Fisheries and Resources Management in Akita Prefecture, Japan

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Three-year Closure of Sailfin sandfish, Arctoscopus japonicus Fisheries and Resources Management in Akita Prefecture, Japan Author: Sugiyama, Hideki, Sakuramoto, Kazumi Research Paper Title: Three-year Closure of Sailfin sandfish, Arctoscopus japonicus Fisheries and Resources Management in Akita Prefecture, Japan Author: Sugiyama, Hideki, Sakuramoto, Kazumi Research Paper Close

• 4. [Article] Predation and food limitation as causes of mortality in larval herring at a spawning ground in British Columbia

  The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/

  Citation × Citation Citation Abstract Copy Title: Predation and food limitation as causes of mortality in larval herring at a spawning ground in British Columbia Author: Purcell, Jennifer E., Grover, Jill J. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Title: Predation and food limitation as causes of mortality in larval herring at a spawning ground in British Columbia Author: Purcell, Jennifer E., Grover, Jill J. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Close

• 5. [Article] Comparison between environmental characteristics of larval bluefin tuna Thunnus thynnus habitat in the Gulf of Mexico and western Mediterranean Sea

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

  Citation × Citation Citation Abstract Copy Title: Comparison between environmental characteristics of larval bluefin tuna Thunnus thynnus habitat in the Gulf of Mexico and western Mediterranean Sea Author: Alemany, Francisco, Reglero, Patricia, Muhling, Barbara A., Ciannelli, Lorenzo, Lamkin, John T., Alvarez-Berastegui, Diego, Roffer, Mitchell A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/home/. Title: Comparison between environmental characteristics of larval bluefin tuna Thunnus thynnus habitat in the Gulf of Mexico and western Mediterranean Sea Author: Alemany, Francisco, Reglero, Patricia, Muhling, Barbara A., Ciannelli, Lorenzo, Lamkin, John T., Alvarez-Berastegui, Diego, Roffer, Mitchell A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/home/. Close

• 6. [Article] Movements of spawning sockeye salmon in Hidden Creek, Brooks Lake, Alaska

  The movements of a population of adult sockeye salmon (Oncorhynchus nerka) were followed in a small tributary of Brooks Lake, Alaska until spawning was nearly complete in 1963. The objectives of the study ...

  Citation × Citation Citation Abstract Copy Title: Movements of spawning sockeye salmon in Hidden Creek, Brooks Lake, Alaska Author: Tsunoda, Setsuwo The movements of a population of adult sockeye salmon (Oncorhynchus nerka) were followed in a small tributary of Brooks Lake, Alaska until spawning was nearly complete in 1963. The objectives of the study were to describe the movements of sockeye salmon on the spawning ground of an entire small stream, to determine factors related to such movements, and to consider the significance of the movements to the species. The spawning run was inventoried at a weir located near the mouth of the tributary. Portions of the run were sampled as they immigrated, and the sampled fish were tagged to enable subsequent identification of individual fish on the spawning ground. Following the initial immigration, daily observations were made to ascertain the location of all fish and the activities of the tagged fish. Tagging had no material effect on either dispersal in the stream or pairing of spawners. The spawning run totalled 2,495; the ratio of males to females was 2.27:1.00, The run consisted preponderantly of males that had spent two winters in the ocean (two ocean-years) and females that had spent three winters in the ocean (three ocean-years). They entered the tributary over a period of 14 days in two waves separated by an interval of three days. The overall median life span in the stream was 12 days in the first wave and eight days in the second wave. The difference was primarily due to predation on the salmon by the brown bear (Ursus arctos). The average female established a redd in 1.4 days; thereafter the females rarely moved far from their redds. The average male required 2.3 days to establish himself in a spawning locale; thereafter most males remained within a relatively small area. The males showed a decided tendency to remain in areas with a high density of females on redds. Fewer females than males overshot their spawning sites. No relation was found between the movements of spawners and either variations of water level or surface water temperature of the stream. Bear predation disrupted spawning activities only locally and temporarily. Males of three ocean-years paired with more females per male than did males of one or two ocean-years. But because of their greater numbers two-ocean-year males participated in more spawnings than did three-ocean-year males. The mean duration of pairing of a particular male with a particular female on a redd was 1.25 days. I concluded that homing within the tributary did not occur; therefore its spawning stock must be a homogeneous unit. The role of the male is primarily one of fertilization of the eggs, not one of defense of territory. Because of the abnormally high ratio of males to females, competition between males for spawning partners resulted in most males of one or two ocean-years being relegated to attend females paired with larger males. Conflict among the males was apparently largely confined within two separate classes of males: males 50 cm or shorter jockeyed among themselves for seemingly preferred positions of attendance next to a pair on a redd, while males 51 cm or longer competed for spawning partners. The polygamous habit in sockeye salmon usually results in a seeming excess of males on the spawning ground beyond the number required to fertilize the eggs. I propose that this "surplus" of males provides a safety factor in times of low numbers in a stock and the competition needed to disperse the males among the available females; both provisions insure fertilization of the available eggs, However, crucial experiments need to be done on an entire population of sockeye salmon with artificially reduced ratios of males to females to determine whether the movements of the spawners would result in an efficiency of egg fertilization sufficient to make harvesting of the "surplus" males feasible. Title: Movements of spawning sockeye salmon in Hidden Creek, Brooks Lake, Alaska Author: Tsunoda, Setsuwo The movements of a population of adult sockeye salmon (Oncorhynchus nerka) were followed in a small tributary of Brooks Lake, Alaska until spawning was nearly complete in 1963. The objectives of the study were to describe the movements of sockeye salmon on the spawning ground of an entire small stream, to determine factors related to such movements, and to consider the significance of the movements to the species. The spawning run was inventoried at a weir located near the mouth of the tributary. Portions of the run were sampled as they immigrated, and the sampled fish were tagged to enable subsequent identification of individual fish on the spawning ground. Following the initial immigration, daily observations were made to ascertain the location of all fish and the activities of the tagged fish. Tagging had no material effect on either dispersal in the stream or pairing of spawners. The spawning run totalled 2,495; the ratio of males to females was 2.27:1.00, The run consisted preponderantly of males that had spent two winters in the ocean (two ocean-years) and females that had spent three winters in the ocean (three ocean-years). They entered the tributary over a period of 14 days in two waves separated by an interval of three days. The overall median life span in the stream was 12 days in the first wave and eight days in the second wave. The difference was primarily due to predation on the salmon by the brown bear (Ursus arctos). The average female established a redd in 1.4 days; thereafter the females rarely moved far from their redds. The average male required 2.3 days to establish himself in a spawning locale; thereafter most males remained within a relatively small area. The males showed a decided tendency to remain in areas with a high density of females on redds. Fewer females than males overshot their spawning sites. No relation was found between the movements of spawners and either variations of water level or surface water temperature of the stream. Bear predation disrupted spawning activities only locally and temporarily. Males of three ocean-years paired with more females per male than did males of one or two ocean-years. But because of their greater numbers two-ocean-year males participated in more spawnings than did three-ocean-year males. The mean duration of pairing of a particular male with a particular female on a redd was 1.25 days. I concluded that homing within the tributary did not occur; therefore its spawning stock must be a homogeneous unit. The role of the male is primarily one of fertilization of the eggs, not one of defense of territory. Because of the abnormally high ratio of males to females, competition between males for spawning partners resulted in most males of one or two ocean-years being relegated to attend females paired with larger males. Conflict among the males was apparently largely confined within two separate classes of males: males 50 cm or shorter jockeyed among themselves for seemingly preferred positions of attendance next to a pair on a redd, while males 51 cm or longer competed for spawning partners. The polygamous habit in sockeye salmon usually results in a seeming excess of males on the spawning ground beyond the number required to fertilize the eggs. I propose that this "surplus" of males provides a safety factor in times of low numbers in a stock and the competition needed to disperse the males among the available females; both provisions insure fertilization of the available eggs, However, crucial experiments need to be done on an entire population of sockeye salmon with artificially reduced ratios of males to females to determine whether the movements of the spawners would result in an efficiency of egg fertilization sufficient to make harvesting of the "surplus" males feasible. Close

• 7. [Article] Differential use of salmon by vertebrate consumers: implications for conservation

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/

  Citation × Citation Citation Abstract Copy Title: Differential use of salmon by vertebrate consumers: implications for conservation Author: Allen, Jennifer M., Wilmers, Christopher C., Wheat, Rachel E., Levi, Taal This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/ Title: Differential use of salmon by vertebrate consumers: implications for conservation Author: Allen, Jennifer M., Wilmers, Christopher C., Wheat, Rachel E., Levi, Taal This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/ Close

• 8. [Article] Effective size of a wild salmonid population is greatly reduced by hatchery supplementation

  This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. To the ...

  Citation × Citation Citation Abstract Copy Title: Effective size of a wild salmonid population is greatly reduced by hatchery supplementation Author: Blouin, M. S., French, R. A., Marine, M. L., Christie, M. R., Waples, R. S. This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Effective size of a wild salmonid population is greatly reduced by hatchery supplementation Author: Blouin, M. S., French, R. A., Marine, M. L., Christie, M. R., Waples, R. S. This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/hdy/index.html. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 9. [Article] Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967

  "Activities included spawning ground and physical stream surveys, sampling of shad and striped bass commercial fisheries, population estimates of juvenile coho in selected streams, evaluating releases ...

  Citation × Citation Citation Abstract Copy Title: Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967 Author: Oregon. Fish Commission. Research Division, Oregon. Pelagic Fisheries and Coastal Rivers Investigation "Activities included spawning ground and physical stream surveys, sampling of shad and striped bass commercial fisheries, population estimates of juvenile coho in selected streams, evaluating releases of adult and fry coho, studying coho in a lake environment, and investigations on the ecology of fall chinook in south coastal streams." (p.1) Title: Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967 Author: Oregon. Fish Commission. Research Division, Oregon. Pelagic Fisheries and Coastal Rivers Investigation "Activities included spawning ground and physical stream surveys, sampling of shad and striped bass commercial fisheries, population estimates of juvenile coho in selected streams, evaluating releases of adult and fry coho, studying coho in a lake environment, and investigations on the ecology of fall chinook in south coastal streams." (p.1) Close

• 10. [Article] Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967

  This report describes the activities of the Coastal Rivers Section, including spawning ground surveys, inventory and obstruction surveys, shad and striped bass landing data, lake rearing studies, the physical ...

  Citation × Citation Citation Abstract Copy Title: Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967 Author: Oregon. Fish Commission. Research Division, Oregon. Pelagic Fisheries and Coastal Rivers Investigation This report describes the activities of the Coastal Rivers Section, including spawning ground surveys, inventory and obstruction surveys, shad and striped bass landing data, lake rearing studies, the physical and chemical characteristics of south coastal streams and various salmonid rearing and ecological studies. Title: Pelagic Fisheries and Coastal Rivers Investigation : progress report, Coastal River section : July 1, 1966-June 30, 1967 Author: Oregon. Fish Commission. Research Division, Oregon. Pelagic Fisheries and Coastal Rivers Investigation This report describes the activities of the Coastal Rivers Section, including spawning ground surveys, inventory and obstruction surveys, shad and striped bass landing data, lake rearing studies, the physical and chemical characteristics of south coastal streams and various salmonid rearing and ecological studies. Close