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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

• 11. [Article] Mass Abundances of Abnormal Pacific Herring Larvae at a Spawning Ground in British Columbia

  Abnormalities including contortion of the body and reduction of the jaws and pectoral fins occurred among 2-25% of the yolk-sac Pacific herring larvae Clupea harengus pallasi collected in 1985 from Kulleet ...

  Citation × Citation Citation Abstract Copy Title: Mass Abundances of Abnormal Pacific Herring Larvae at a Spawning Ground in British Columbia Author: Purcell, Jennifer E., Grosse, Daniel, Grover, Jill J. Abnormalities including contortion of the body and reduction of the jaws and pectoral fins occurred among 2-25% of the yolk-sac Pacific herring larvae Clupea harengus pallasi collected in 1985 from Kulleet Bay, a spawning area on Vancouver Island, British Columbia. An additional 4-68% of the post-yolk-sac larvae had underdeveloped lower jaws. Abnormal larvae were distinguished from healthy larvae through discriminant analysis of morphomelric characters. The high frequency of larval abnormalities in 1985 may have been related to unseasonably sunny, warm weather during the 14-d incubation of the eggs, which resulted in stress to eggs exposed to sun and warm air during especially low midday tides. Underdeveloped jaws affected feeding by postyolk-sac larvae, as evidenced by lack of food in the guts and by shallow body depths characteristic of starvation. Title: Mass Abundances of Abnormal Pacific Herring Larvae at a Spawning Ground in British Columbia Author: Purcell, Jennifer E., Grosse, Daniel, Grover, Jill J. Abnormalities including contortion of the body and reduction of the jaws and pectoral fins occurred among 2-25% of the yolk-sac Pacific herring larvae Clupea harengus pallasi collected in 1985 from Kulleet Bay, a spawning area on Vancouver Island, British Columbia. An additional 4-68% of the post-yolk-sac larvae had underdeveloped lower jaws. Abnormal larvae were distinguished from healthy larvae through discriminant analysis of morphomelric characters. The high frequency of larval abnormalities in 1985 may have been related to unseasonably sunny, warm weather during the 14-d incubation of the eggs, which resulted in stress to eggs exposed to sun and warm air during especially low midday tides. Underdeveloped jaws affected feeding by postyolk-sac larvae, as evidenced by lack of food in the guts and by shallow body depths characteristic of starvation. Close

• 12. [Article] A Prototype Study for Evaluation of Algal Beds

  Research Paper

  Citation × Citation Citation Abstract Copy Title: A Prototype Study for Evaluation of Algal Beds Author: Takashima, Yoshikazu, Kaneko, Tomomi Research Paper Title: A Prototype Study for Evaluation of Algal Beds Author: Takashima, Yoshikazu, Kaneko, Tomomi Research Paper Close

• 13. [Article] A game theoretic bargaining framework for cooperative management of the Pacific sardine

  Presentation

  Citation × Citation Citation Abstract Copy Title: A game theoretic bargaining framework for cooperative management of the Pacific sardine Author: McFarlane, Sandy, Anderson, Chris, Gallucci, Vincent, Hariharan, Aneesh Presentation Title: A game theoretic bargaining framework for cooperative management of the Pacific sardine Author: McFarlane, Sandy, Anderson, Chris, Gallucci, Vincent, Hariharan, Aneesh Presentation Close

• 14. [Article] Behavior and survival of coho salmon, Oncorhynchus kisutch (Walbaum), in Sashin Creek, southeastern Alaska

  Behavior and survival in fresh water were studied for three brood years of coho salmon in Sashin Creek, Alaska, from October 1963, until September 1966. Investigations of spawning adults were conducted ...

  Citation × Citation Citation Abstract Copy Title: Behavior and survival of coho salmon, Oncorhynchus kisutch (Walbaum), in Sashin Creek, southeastern Alaska Author: Crone, Richard Allan Behavior and survival in fresh water were studied for three brood years of coho salmon in Sashin Creek, Alaska, from October 1963, until September 1966. Investigations of spawning adults were conducted to determine numbers of spawners, distribution on the spawning grounds, effects on pink salmon, age composition, redd life, fecundities, and egg retention. Juvenile coho were studied to determine changes in population size, distribution in the stream, age composition of the population, food habits, and rates of mortality during fresh-water life. The number of coho spawners counted into Sashin Creek each year normally varied from 50 to 300. Weir counts and estimations of the number of spawners determined from observed spawning effort and redd life were not accurate methods of estimating the coho escapement into Sashin Creek. In 1965, a more accurate estimate was obtained by tagging a portion of the run and recording marked to unmarked ratios on the spawning grounds. I estimated that less than two percent of the viable pink salmon embryos were destroyed in 1965 by the spawning activities of coho salmon. Most coho spawners returned to Sashin Creek in 1965 and 1966 in their fourth year of life after having migrated to sea in their third year (designated 4₃). Smaller numbers of 3₂ and 5₄ individuals composed the remainder of the spawning population. The mean redd life of 56 females was 13 days. A small sample of coho from Sashin Creek examined for fecundity in 1966 gave a mean of 2,868 eggs per female. A weir or fyke net was fished in the spring to estimate emigration of juvenile coho. Coho smolts left Sashin Creek from April through July; peak emigration occurred in late May or early June. Coho fry left the stream in the spring and summer in widely varying numbers from year to year. I estimated from growth data, population estimates, and analysis of scale samples that most coho juveniles remained in Sashin Creek for two growing seasons before migrating to sea. Analysis of scales from juvenile coho indicated that some reabsorption of scales occurs during the winter. The possibility of reabsorption of circuli makes back-calculation of the length of younger age-groups of coho from scale measurements unreliable. Diptera were represented more often than any other order of insects in the stomachs of juvenile coho. Hemiptera were important as food items to juvenile coho in a tributary stream. The estimated survival from egg deposition to immediately prior to emergence varied between 17.5 and. 34.9 percent for the three brood years, and averaged 27. 8 percent. Early summer populations of fry were variable in size and dependent on the size of the egg deposition of the brood. Populations of fry declined rapidly during July and early August. Instantaneous mortality rates were much higher for this period than during any other time in the fresh-water life of coho salmon in Sashin Creek. Mortality dropped to a low level during the following winter period. Title: Behavior and survival of coho salmon, Oncorhynchus kisutch (Walbaum), in Sashin Creek, southeastern Alaska Author: Crone, Richard Allan Behavior and survival in fresh water were studied for three brood years of coho salmon in Sashin Creek, Alaska, from October 1963, until September 1966. Investigations of spawning adults were conducted to determine numbers of spawners, distribution on the spawning grounds, effects on pink salmon, age composition, redd life, fecundities, and egg retention. Juvenile coho were studied to determine changes in population size, distribution in the stream, age composition of the population, food habits, and rates of mortality during fresh-water life. The number of coho spawners counted into Sashin Creek each year normally varied from 50 to 300. Weir counts and estimations of the number of spawners determined from observed spawning effort and redd life were not accurate methods of estimating the coho escapement into Sashin Creek. In 1965, a more accurate estimate was obtained by tagging a portion of the run and recording marked to unmarked ratios on the spawning grounds. I estimated that less than two percent of the viable pink salmon embryos were destroyed in 1965 by the spawning activities of coho salmon. Most coho spawners returned to Sashin Creek in 1965 and 1966 in their fourth year of life after having migrated to sea in their third year (designated 4₃). Smaller numbers of 3₂ and 5₄ individuals composed the remainder of the spawning population. The mean redd life of 56 females was 13 days. A small sample of coho from Sashin Creek examined for fecundity in 1966 gave a mean of 2,868 eggs per female. A weir or fyke net was fished in the spring to estimate emigration of juvenile coho. Coho smolts left Sashin Creek from April through July; peak emigration occurred in late May or early June. Coho fry left the stream in the spring and summer in widely varying numbers from year to year. I estimated from growth data, population estimates, and analysis of scale samples that most coho juveniles remained in Sashin Creek for two growing seasons before migrating to sea. Analysis of scales from juvenile coho indicated that some reabsorption of scales occurs during the winter. The possibility of reabsorption of circuli makes back-calculation of the length of younger age-groups of coho from scale measurements unreliable. Diptera were represented more often than any other order of insects in the stomachs of juvenile coho. Hemiptera were important as food items to juvenile coho in a tributary stream. The estimated survival from egg deposition to immediately prior to emergence varied between 17.5 and. 34.9 percent for the three brood years, and averaged 27. 8 percent. Early summer populations of fry were variable in size and dependent on the size of the egg deposition of the brood. Populations of fry declined rapidly during July and early August. Instantaneous mortality rates were much higher for this period than during any other time in the fresh-water life of coho salmon in Sashin Creek. Mortality dropped to a low level during the following winter period. Close

• 15. [Article] Spawning phenology and geography of Aleutian Islands and eastern Bering Sea Pacific cod (Gadus macrocephalus)

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

  Citation × Citation Citation Abstract Copy Title: Spawning phenology and geography of Aleutian Islands and eastern Bering Sea Pacific cod (Gadus macrocephalus) Author: Neidetcher, Sandra K., Ciannelli, Lorenzo, Logerwell, Elizabeth A., Hurst, Thomas P. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/deep-sea-research-part-ii-topical-studies-in-oceanography. Title: Spawning phenology and geography of Aleutian Islands and eastern Bering Sea Pacific cod (Gadus macrocephalus) Author: Neidetcher, Sandra K., Ciannelli, Lorenzo, Logerwell, Elizabeth A., Hurst, Thomas P. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/deep-sea-research-part-ii-topical-studies-in-oceanography. Close

• 16. [Article] Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature

  Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial ...

  Citation × Citation Citation Abstract Copy Title: Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature Author: LovellFord, Rachel Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement to spawning grounds. These cues may also provide usable habitat for migration and spawning. River discharge, temperature, and length of day have long been assumed to be the environmental cues which trigger migration and spawning of coho salmon as coho return within the same season each year to spawn. Hatchery studies have also shown that the timing of reproductive behavior is heritable. If this heritability is determined by the fluvial conditions of the spawning grounds, then a predictable relationship should exist between reproductive behavior and the hydrologic and thermal regimes. Surprisingly, no defensible correlations between discharge thresholds and spawning or migrating activity have been identified for naturally reproducing coho salmon. Thermal, velocity, and depth limitations have been identified for coho salmon, but these values have not been examined in combination or within the context of a hydrologic and thermal regime. This study compares interannual patterns in the timing of coho mid-river migration in the North Umqua (180 km up river from the estuary) and the initiation of spawn timing in the Smith River basins (Oregon) with river discharge and water temperature data to ascertain whether these behaviors are driven by fluvial conditions. Additionally, we used this data to identify the window over which most migration and spawning takes place in our test systems. On the North Umpqua, coho salmon mid-river migration initiated (first 5% of migrants) after summer peak temperatures and following a threshold average daily temperature of 18 C°, but before fall storm events occurred. In most years, approximately 75% of the migrating coho salmon have moved past the Winchester Dam before fall storms initiated and when discharge remained less than the 11 year average for the month of November, more similar to summer than winter flow levels. Additionally, characteristic lengths and numbers of peaks within the distribution of annual migrations were attributable to the generational cohort that the migration belonged to despite the similarity in population size across all years. These patterns in the distribution of generational cohorts suggest an inherited timing response as well as highlight cohorts which may contain diminished sub-populations. The initiation of coho salmon spawning appears limited both by a thermal threshold of 12 C° in all basins, as well as by a minimal discharge threshold, which is unique to each stream. Continued spawning activity occurs as discharge remains elevated from fall levels. It is also notable that there was no statistical difference in the date of the initiation of spawning within each basin in a given year or across years at a given site. Together, these studies highlight the important role that the coho salmon genome plays in reproductive timing as well as the ways that fluvial thresholds limit reproductive behavior in time. Coho have survived because of their genome has been resilient when faced with environmental change. Future work should consider variability in fluvial conditions relative to coho salmon phenotypic plasticity over time. Coho salmon phenotypic plasticity will determine whether the rate of change of the hydrologic and thermal regimes important to coho salmon survival outpaces the coho’s ability to adapt. This study contributed to this future work by establishing baseline relationships between the behavior of a threatened species and measurable environmental thresholds. Title: Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature Author: LovellFord, Rachel Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement to spawning grounds. These cues may also provide usable habitat for migration and spawning. River discharge, temperature, and length of day have long been assumed to be the environmental cues which trigger migration and spawning of coho salmon as coho return within the same season each year to spawn. Hatchery studies have also shown that the timing of reproductive behavior is heritable. If this heritability is determined by the fluvial conditions of the spawning grounds, then a predictable relationship should exist between reproductive behavior and the hydrologic and thermal regimes. Surprisingly, no defensible correlations between discharge thresholds and spawning or migrating activity have been identified for naturally reproducing coho salmon. Thermal, velocity, and depth limitations have been identified for coho salmon, but these values have not been examined in combination or within the context of a hydrologic and thermal regime. This study compares interannual patterns in the timing of coho mid-river migration in the North Umqua (180 km up river from the estuary) and the initiation of spawn timing in the Smith River basins (Oregon) with river discharge and water temperature data to ascertain whether these behaviors are driven by fluvial conditions. Additionally, we used this data to identify the window over which most migration and spawning takes place in our test systems. On the North Umpqua, coho salmon mid-river migration initiated (first 5% of migrants) after summer peak temperatures and following a threshold average daily temperature of 18 C°, but before fall storm events occurred. In most years, approximately 75% of the migrating coho salmon have moved past the Winchester Dam before fall storms initiated and when discharge remained less than the 11 year average for the month of November, more similar to summer than winter flow levels. Additionally, characteristic lengths and numbers of peaks within the distribution of annual migrations were attributable to the generational cohort that the migration belonged to despite the similarity in population size across all years. These patterns in the distribution of generational cohorts suggest an inherited timing response as well as highlight cohorts which may contain diminished sub-populations. The initiation of coho salmon spawning appears limited both by a thermal threshold of 12 C° in all basins, as well as by a minimal discharge threshold, which is unique to each stream. Continued spawning activity occurs as discharge remains elevated from fall levels. It is also notable that there was no statistical difference in the date of the initiation of spawning within each basin in a given year or across years at a given site. Together, these studies highlight the important role that the coho salmon genome plays in reproductive timing as well as the ways that fluvial thresholds limit reproductive behavior in time. Coho have survived because of their genome has been resilient when faced with environmental change. Future work should consider variability in fluvial conditions relative to coho salmon phenotypic plasticity over time. Coho salmon phenotypic plasticity will determine whether the rate of change of the hydrologic and thermal regimes important to coho salmon survival outpaces the coho’s ability to adapt. This study contributed to this future work by establishing baseline relationships between the behavior of a threatened species and measurable environmental thresholds. Close

• 17. [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

• 18. [Article] Cormorant harassment to protect juvenile salmonids in Tillamook County, Oregon

  The goal of the Oregon Plan is to restore wild coho and wild steelhead runs. Under the federal Endangered Species Act, wild coho salmon along the Oregon Coast are listed as Threatened and wild Oregon Coast ...

  Citation × Citation Citation Abstract Copy Title: Cormorant harassment to protect juvenile salmonids in Tillamook County, Oregon Author: Bayer, Range D., 1947- The goal of the Oregon Plan is to restore wild coho and wild steelhead runs. Under the federal Endangered Species Act, wild coho salmon along the Oregon Coast are listed as Threatened and wild Oregon Coast steelhead are a candidate for listing. Although cormorants have been hazed at the Nehalem Estuary for at least 10 years and at the Tillamook and Nestucca Estuaries for at least three years, spawning ground counts of wild coho salmon, winter steelhead, and fall chinook have averaged less since hazing began. Thus, hazing does not appear to be useful in recovering wild salmonids. Hazing is not correlated with consistently improved hatchery returns. The survival of Coded Wire Tag marked coho smolts at the Nehalem was about the same whether hazing occurred or not, the percent return for coho smolts was not significantly greater at the hazed Nehalem than at the nonhazed Salmon River, and the number of returning adult coho salmon was significantly greater with hazing at the Nehalem hatchery but not at the Trask hatchery in the Tillamook Basin. For winter steelhead, the number of returning adults to the Nehalem and jacks to the Cedar Creek hatchery in the Nestucca Basin did not increase significantly with hazing, but the number of jacks returning to the Nehalem did. Changes in fisheries subsequent to hazing are mixed. Coho catches increased with hazing at the Nehalem but not at the Tillamook Basin. Nehalem steelhead catches averaged less with hazing, but chinook fisheries have grown. However, the increase in chinook catches occurred as the number of wild chinook at spawning areas declined, so the larger catch may be a consequence of a greater harvest of wild chinook rather than hazing. Returns may not have increased with hazing because it was ineffective in substantially reducing predation, because smolts saved by hazing died anyway, or because other factors such as unfavorable ocean conditions may have been much more important in affecting smolt survival than hazing. In any case, hazing does not appear to be a panacea for salmonid recovery, and it has costs. During 1996-1999, the Oregon Legislature spent $100,000 for cormorant hazing, and a biological cost of hazing is the disturbance of wildlife other than cormorants. Title: Cormorant harassment to protect juvenile salmonids in Tillamook County, Oregon Author: Bayer, Range D., 1947- The goal of the Oregon Plan is to restore wild coho and wild steelhead runs. Under the federal Endangered Species Act, wild coho salmon along the Oregon Coast are listed as Threatened and wild Oregon Coast steelhead are a candidate for listing. Although cormorants have been hazed at the Nehalem Estuary for at least 10 years and at the Tillamook and Nestucca Estuaries for at least three years, spawning ground counts of wild coho salmon, winter steelhead, and fall chinook have averaged less since hazing began. Thus, hazing does not appear to be useful in recovering wild salmonids. Hazing is not correlated with consistently improved hatchery returns. The survival of Coded Wire Tag marked coho smolts at the Nehalem was about the same whether hazing occurred or not, the percent return for coho smolts was not significantly greater at the hazed Nehalem than at the nonhazed Salmon River, and the number of returning adult coho salmon was significantly greater with hazing at the Nehalem hatchery but not at the Trask hatchery in the Tillamook Basin. For winter steelhead, the number of returning adults to the Nehalem and jacks to the Cedar Creek hatchery in the Nestucca Basin did not increase significantly with hazing, but the number of jacks returning to the Nehalem did. Changes in fisheries subsequent to hazing are mixed. Coho catches increased with hazing at the Nehalem but not at the Tillamook Basin. Nehalem steelhead catches averaged less with hazing, but chinook fisheries have grown. However, the increase in chinook catches occurred as the number of wild chinook at spawning areas declined, so the larger catch may be a consequence of a greater harvest of wild chinook rather than hazing. Returns may not have increased with hazing because it was ineffective in substantially reducing predation, because smolts saved by hazing died anyway, or because other factors such as unfavorable ocean conditions may have been much more important in affecting smolt survival than hazing. In any case, hazing does not appear to be a panacea for salmonid recovery, and it has costs. During 1996-1999, the Oregon Legislature spent $100,000 for cormorant hazing, and a biological cost of hazing is the disturbance of wildlife other than cormorants. Close

• 19. [Article] Sustainability of Coastal Fisheries in Hiroshima Prefecture, Japan: Scope of Community-Based Management Approach to Achieve the Aims of Current Japanese Coastal Fishery Policy

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Sustainability of Coastal Fisheries in Hiroshima Prefecture, Japan: Scope of Community-Based Management Approach to Achieve the Aims of Current Japanese Coastal Fishery Policy Author: Yamao, Mashiro, Oliva, Luis Research Paper Title: Sustainability of Coastal Fisheries in Hiroshima Prefecture, Japan: Scope of Community-Based Management Approach to Achieve the Aims of Current Japanese Coastal Fishery Policy Author: Yamao, Mashiro, Oliva, Luis Research Paper Close

• 20. [Article] The potential of Indonesian mangrove forests for global climate change mitigation

  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 the author(s) ...

  Citation × Citation Citation Abstract Copy Title: The potential of Indonesian mangrove forests for global climate change mitigation Author: Kauffman, J. Boone, Murdiyarso, Daniel, et al., Purbopuspito, Joko 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 the author(s) and published by Nature Publishing Group. The published article can be found at: http://www.nature.com/nclimate/index.html Title: The potential of Indonesian mangrove forests for global climate change mitigation Author: Kauffman, J. Boone, Murdiyarso, Daniel, et al., Purbopuspito, Joko 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 the author(s) and published by Nature Publishing Group. The published article can be found at: http://www.nature.com/nclimate/index.html Close

• 21. [Article] Maximizing economic yield from a plankton feeding fish population on high latitudes

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Maximizing economic yield from a plankton feeding fish population on high latitudes Author: Eide, Arne, Flaaten, Ola, Henriksen, Edgar Abstract only. Title: Maximizing economic yield from a plankton feeding fish population on high latitudes Author: Eide, Arne, Flaaten, Ola, Henriksen, Edgar Abstract only. Close

• 22. [Article] Tev (total Economic Value) Analysis of A Marine Environment in Norway

  The push for ecosystem based management has opened up not only for including more of the natural systems when managing fish resources, but also a broader perspective on the human systems, and the diverse ...

  Citation × Citation Citation Abstract Copy Title: Tev (total Economic Value) Analysis of A Marine Environment in Norway Author: Kahui, Viktoria, Armstrong, Claire, Aanesen, Margrethe The push for ecosystem based management has opened up not only for including more of the natural systems when managing fish resources, but also a broader perspective on the human systems, and the diverse activities in the sea. This is reflected for instance in the EU Maritime Policy where fisheries is just one of many activities that marine management must take into account. Research into valuation of natural resources has shown that non-use values may be substantial in the marine environment; These are e.g. existence values, such as the existence of rare species and benthic components such as corals, and option values with regard to potential future applications, e.g. in marine bioprospecting. In addition, indirect use values, such as habitat values, recreational values and nutrient cycling often far exceed the direct use values, which are typically the value of the fisheries, aquaculture and marine tourism. Applying and critiquing the Total Economic Value (TEV) set up, we have estimated marine direct use values, including fisheries and aquaculture, indirect use values and non-use values in Nordland county in Norway, specifically connected to the Lofoten-Vesterålen marine area. Lofoten-Vesterålen is the most important spawning ground for commercial fish resources such as cod and herring, and it is also a very popular tourist destination. Yet when studying some of the other values that the marine environment supplies, these traditional values are not necessarily the most important. Title: Tev (total Economic Value) Analysis of A Marine Environment in Norway Author: Kahui, Viktoria, Armstrong, Claire, Aanesen, Margrethe The push for ecosystem based management has opened up not only for including more of the natural systems when managing fish resources, but also a broader perspective on the human systems, and the diverse activities in the sea. This is reflected for instance in the EU Maritime Policy where fisheries is just one of many activities that marine management must take into account. Research into valuation of natural resources has shown that non-use values may be substantial in the marine environment; These are e.g. existence values, such as the existence of rare species and benthic components such as corals, and option values with regard to potential future applications, e.g. in marine bioprospecting. In addition, indirect use values, such as habitat values, recreational values and nutrient cycling often far exceed the direct use values, which are typically the value of the fisheries, aquaculture and marine tourism. Applying and critiquing the Total Economic Value (TEV) set up, we have estimated marine direct use values, including fisheries and aquaculture, indirect use values and non-use values in Nordland county in Norway, specifically connected to the Lofoten-Vesterålen marine area. Lofoten-Vesterålen is the most important spawning ground for commercial fish resources such as cod and herring, and it is also a very popular tourist destination. Yet when studying some of the other values that the marine environment supplies, these traditional values are not necessarily the most important. Close

• 23. [Article] Natal source contributions of Pacific cod (Gadus macrocephalus) recruits in the southeastern Bering Sea

  Effective and sustainable fisheries management not only depends on identifying and defining stocks (fundamental unit of management), but also on having knowledge of factors influencing the abundance, distribution ...

  Citation × Citation Citation Abstract Copy Title: Natal source contributions of Pacific cod (Gadus macrocephalus) recruits in the southeastern Bering Sea Author: DiMaria, Ruth A. Effective and sustainable fisheries management not only depends on identifying and defining stocks (fundamental unit of management), but also on having knowledge of factors influencing the abundance, distribution and connectivity of stocks. Population structure of Pacific cod (Gadus macrocephalus) in the southeastern Bering Sea (EBS) remains unresolved although genetic data indicate isolation-by-distance throughout the species range across the North Pacific Ocean. Pacific cod are fished on their spawning grounds, therefore, it is important to evaluate whether particular spawning sources are more critical than others in sustaining the productivity of fished populations. Chemical analysis of otoliths can provide information on mixing among groups of fish on ecological time scales and at finer spatial scales than genetic analyses. Therefore, I completed laboratory and field research on the otolith elemental composition of larval and juvenile cod to: (1) investigate temperature and growth-rate effects on otolith elemental incorporation to aid interpretations of field data; (2) evaluate the potential to detect larval exchange between the Gulf of Alaska (GOA) and the EBS; (3) quantify spatial scales at which there was significant variation in otolith elemental composition; and (4) quantify the number of larval sources (chemically distinct groups) contributing to juvenile recruits in the EBS. In the laboratory study, I observed higher rates of incorporation at lower temperatures for both Sr and Ba but similar ranges of Mg incorporation at 2°C, 6°C and 8°C. There was no significant effect of somatic growth or otolith precipitation rate on elemental incorporation detected, indicating that variation in individual growth rates should not confound interpretations of field data. In two years of field collections (2006 & 2008), otolith elemental signatures (Mg:Ca, Mn:Ca, Zn:Ca, Sr:Ca, and Ba:Ca) differed between larvae collected in the EBS and GOA, and over 70% of the larvae were correctly classified to source. Furthermore, I examined the chemical signatures of the otolith edge (representing approximately the last 10 d of life) for juveniles collected at six locations throughout the EBS. Seventy-nine and 71% of the juveniles were correctly classified to their collection location in 2006 and 2008, respectively. These results demonstrate that there is sufficient spatial variation in otolith composition to examine spatial structure in Pacific cod within the EBS and to identify GOA larval contribution to the EBS population. Finally, larval source signatures, represented by otolith core chemistry, of juveniles collected throughout the EBS were classified into chemically distinct groups using hierarchical cluster analysis. In both years we identified two dominant sources representing 56% and 30% of the cohort in 2006, and 53% and 40% in 2008. Most collection sites contained a mixture of larval sources although one or two sites per year were comprised of a single source. These chemically unique sources likely represent different spawning locations with distinct environmental characteristics, although the exact locations are unknown. These sources potentially represent contributions from known spawning areas, which include the Alaskan Peninsula, Aleutian Islands, and Pribilof Islands. Our results highlight the potential of otolith chemical analyses to identify source contributions of Pacific cod in the EBS but larval collections throughout the spawning season are needed to provide additional detail on the spatial distribution of those sources. Title: Natal source contributions of Pacific cod (Gadus macrocephalus) recruits in the southeastern Bering Sea Author: DiMaria, Ruth A. Effective and sustainable fisheries management not only depends on identifying and defining stocks (fundamental unit of management), but also on having knowledge of factors influencing the abundance, distribution and connectivity of stocks. Population structure of Pacific cod (Gadus macrocephalus) in the southeastern Bering Sea (EBS) remains unresolved although genetic data indicate isolation-by-distance throughout the species range across the North Pacific Ocean. Pacific cod are fished on their spawning grounds, therefore, it is important to evaluate whether particular spawning sources are more critical than others in sustaining the productivity of fished populations. Chemical analysis of otoliths can provide information on mixing among groups of fish on ecological time scales and at finer spatial scales than genetic analyses. Therefore, I completed laboratory and field research on the otolith elemental composition of larval and juvenile cod to: (1) investigate temperature and growth-rate effects on otolith elemental incorporation to aid interpretations of field data; (2) evaluate the potential to detect larval exchange between the Gulf of Alaska (GOA) and the EBS; (3) quantify spatial scales at which there was significant variation in otolith elemental composition; and (4) quantify the number of larval sources (chemically distinct groups) contributing to juvenile recruits in the EBS. In the laboratory study, I observed higher rates of incorporation at lower temperatures for both Sr and Ba but similar ranges of Mg incorporation at 2°C, 6°C and 8°C. There was no significant effect of somatic growth or otolith precipitation rate on elemental incorporation detected, indicating that variation in individual growth rates should not confound interpretations of field data. In two years of field collections (2006 & 2008), otolith elemental signatures (Mg:Ca, Mn:Ca, Zn:Ca, Sr:Ca, and Ba:Ca) differed between larvae collected in the EBS and GOA, and over 70% of the larvae were correctly classified to source. Furthermore, I examined the chemical signatures of the otolith edge (representing approximately the last 10 d of life) for juveniles collected at six locations throughout the EBS. Seventy-nine and 71% of the juveniles were correctly classified to their collection location in 2006 and 2008, respectively. These results demonstrate that there is sufficient spatial variation in otolith composition to examine spatial structure in Pacific cod within the EBS and to identify GOA larval contribution to the EBS population. Finally, larval source signatures, represented by otolith core chemistry, of juveniles collected throughout the EBS were classified into chemically distinct groups using hierarchical cluster analysis. In both years we identified two dominant sources representing 56% and 30% of the cohort in 2006, and 53% and 40% in 2008. Most collection sites contained a mixture of larval sources although one or two sites per year were comprised of a single source. These chemically unique sources likely represent different spawning locations with distinct environmental characteristics, although the exact locations are unknown. These sources potentially represent contributions from known spawning areas, which include the Alaskan Peninsula, Aleutian Islands, and Pribilof Islands. Our results highlight the potential of otolith chemical analyses to identify source contributions of Pacific cod in the EBS but larval collections throughout the spawning season are needed to provide additional detail on the spatial distribution of those sources. Close

• 24. [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

• 25. [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

• 26. [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

• 27. [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

• 28. [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

• 29. [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

• 30. [Article] Distribution, Abundance, and Settlement of Slope-spawning Flatfish during Early Life Stages in the Eastern Bering Sea

  Changes in environmental conditions in marine ecosystems could directly or indirectly influence distribution, abundance, settlement, and size at settlement of flatfish. Understanding species-specific and ...

  Citation × Citation Citation Abstract Copy Title: Distribution, Abundance, and Settlement of Slope-spawning Flatfish during Early Life Stages in the Eastern Bering Sea Author: Sohn, Dongwha Changes in environmental conditions in marine ecosystems could directly or indirectly influence distribution, abundance, settlement, and size at settlement of flatfish. Understanding species-specific and age-specific responses to environmental variability is important for managing commercially important flatfish stocks. Slope-spawning flatfish whose offspring rely on extensive drift from the slope (spawning) to the shelf (settlement) and which require specific habitat for settlement could be especially vulnerable to environmental variability. Arrowtooth flounder (ATF; Atheresthes stomias), Greenland halibut (GH; Reinhardtius hippoglossoides), and Pacific halibut (PH; Hippoglossus stenolepis) are commercially and ecologically important slope-spawning flatfish species in the eastern Bering Sea (EBS), which has experienced fluctuating warm and cold periods since 2000. Although the three species share many attributes, their population trajectories have fluctuated differently. This difference could result from contrasting responses to environmental variability during early life history. To understand how physical variability of the Bering Sea can differentially affect flatfish ecology from pre-settlement to post-settlement phases, I used a combination of field data, biophysical modeling, and statistical modeling to characterize early life stage attributes (chapter 2), settlement success (chapter 3), and size, abundance, and distribution at settlement (age-0) and age-1 (chapter 4). Based on historical ichthyoplankton survey data for GH and PH, I found that there were species-specific differences in the spatial distribution (vertically and horizontally) and juvenile nursery areas between the two species during early life stages in the EBS. Specifically, I found that PH larvae abruptly move to shallower water as they grow, and cross onto the shelf earlier than GH. This ontogenetic movement has the benefit of allowing PH larvae to take advantage of on-shelf transport to reach their settlement locations. However, an early transition from the slope to the shelf may not equally benefit GH, whose settlement locations are further from the spawning ground. Using a bio-physical modeling approach parameterized on the field data summarized in chapter 2, I found that species-specific variability of early life attributes causes interannual and species-specific variability of GH and PH settlement success in the EBS. GH settlement increased with increasing along-shelf (northwestward) flow whereas PH settlement decreased. GH that spawned in November and December were highly successful at settling while PH settlement was most successful when they spawned in January and February. Furthermore, GH settlement is affected by temperature dependence of pelagic larval duration, but not PH, indicating a strong resilience of PH to temperature induced variations in development and dispersal duration. Using otolith microstructure analysis, I found that variations in size at settlement for ATF are significantly correlated with latitude of sampling location. For GH, their size at settlement is associated with bottom water temperature and sea ice extent. Especially, sea ice coverage has a strong negative correlation with on-shelf winds, which drive along-shelf Ekman transport to southeast impacting dispersal pathways and duration. Size at settlement for ATF increased with increasing latitude of sampling location, which could be impacted by currents. For GH, size at settlement decreased with decreasing bottom water temperature and increasing sea ice extent. Also, my results showed that settlement habitat increases for GH in cold years whereas that of ATF increases in warm years. The bottom temperature of age-0 habitat for both ATF and GH affected on their age-1 abundance; GH age-1 abundance increased with decreasing bottom temperature of age-0 habitat, but no clear directionality was found for ATF. The findings from this study have implications for understanding settlement success and recruitment of slope-spawning flatfish in the EBS. In most cold years when along-shelf flow is generally strong, the level of larval supply of GH to their settlement areas is higher than in warm years. Size at settlement for GH decreased in cold years. The larger amount of suitable habitat for settlement and post-settlement stages could result in lower competition and less predation in comparison to warm years. In support of this hypothesis, I found greater age-1 abundance in cold years, indicating size at settlement in GH may not be critical compared to suitability of habitat features and larval supply to settlement grounds. On the other hand, in cold years with strong along-shelf transport to northwest, PH (or ATF), which settle in the southern part of the EBS, have lower numbers of successful settlers. Size at settlement for ATF increased in cold years, and I assumed that size at settlement for PH may have similar patterns. The amount of suitable habitat after settlement would be smaller, resulting in lower recruitment due to increased competition for limited resources. By studying how physical factors and their variability influence these three flatfish during early life stages, this study provides valuable insight into the response of flatfish stocks to past and future climate changes in the eastern Bering Sea – a system that is especially vulnerable to warming. Title: Distribution, Abundance, and Settlement of Slope-spawning Flatfish during Early Life Stages in the Eastern Bering Sea Author: Sohn, Dongwha Changes in environmental conditions in marine ecosystems could directly or indirectly influence distribution, abundance, settlement, and size at settlement of flatfish. Understanding species-specific and age-specific responses to environmental variability is important for managing commercially important flatfish stocks. Slope-spawning flatfish whose offspring rely on extensive drift from the slope (spawning) to the shelf (settlement) and which require specific habitat for settlement could be especially vulnerable to environmental variability. Arrowtooth flounder (ATF; Atheresthes stomias), Greenland halibut (GH; Reinhardtius hippoglossoides), and Pacific halibut (PH; Hippoglossus stenolepis) are commercially and ecologically important slope-spawning flatfish species in the eastern Bering Sea (EBS), which has experienced fluctuating warm and cold periods since 2000. Although the three species share many attributes, their population trajectories have fluctuated differently. This difference could result from contrasting responses to environmental variability during early life history. To understand how physical variability of the Bering Sea can differentially affect flatfish ecology from pre-settlement to post-settlement phases, I used a combination of field data, biophysical modeling, and statistical modeling to characterize early life stage attributes (chapter 2), settlement success (chapter 3), and size, abundance, and distribution at settlement (age-0) and age-1 (chapter 4). Based on historical ichthyoplankton survey data for GH and PH, I found that there were species-specific differences in the spatial distribution (vertically and horizontally) and juvenile nursery areas between the two species during early life stages in the EBS. Specifically, I found that PH larvae abruptly move to shallower water as they grow, and cross onto the shelf earlier than GH. This ontogenetic movement has the benefit of allowing PH larvae to take advantage of on-shelf transport to reach their settlement locations. However, an early transition from the slope to the shelf may not equally benefit GH, whose settlement locations are further from the spawning ground. Using a bio-physical modeling approach parameterized on the field data summarized in chapter 2, I found that species-specific variability of early life attributes causes interannual and species-specific variability of GH and PH settlement success in the EBS. GH settlement increased with increasing along-shelf (northwestward) flow whereas PH settlement decreased. GH that spawned in November and December were highly successful at settling while PH settlement was most successful when they spawned in January and February. Furthermore, GH settlement is affected by temperature dependence of pelagic larval duration, but not PH, indicating a strong resilience of PH to temperature induced variations in development and dispersal duration. Using otolith microstructure analysis, I found that variations in size at settlement for ATF are significantly correlated with latitude of sampling location. For GH, their size at settlement is associated with bottom water temperature and sea ice extent. Especially, sea ice coverage has a strong negative correlation with on-shelf winds, which drive along-shelf Ekman transport to southeast impacting dispersal pathways and duration. Size at settlement for ATF increased with increasing latitude of sampling location, which could be impacted by currents. For GH, size at settlement decreased with decreasing bottom water temperature and increasing sea ice extent. Also, my results showed that settlement habitat increases for GH in cold years whereas that of ATF increases in warm years. The bottom temperature of age-0 habitat for both ATF and GH affected on their age-1 abundance; GH age-1 abundance increased with decreasing bottom temperature of age-0 habitat, but no clear directionality was found for ATF. The findings from this study have implications for understanding settlement success and recruitment of slope-spawning flatfish in the EBS. In most cold years when along-shelf flow is generally strong, the level of larval supply of GH to their settlement areas is higher than in warm years. Size at settlement for GH decreased in cold years. The larger amount of suitable habitat for settlement and post-settlement stages could result in lower competition and less predation in comparison to warm years. In support of this hypothesis, I found greater age-1 abundance in cold years, indicating size at settlement in GH may not be critical compared to suitability of habitat features and larval supply to settlement grounds. On the other hand, in cold years with strong along-shelf transport to northwest, PH (or ATF), which settle in the southern part of the EBS, have lower numbers of successful settlers. Size at settlement for ATF increased in cold years, and I assumed that size at settlement for PH may have similar patterns. The amount of suitable habitat after settlement would be smaller, resulting in lower recruitment due to increased competition for limited resources. By studying how physical factors and their variability influence these three flatfish during early life stages, this study provides valuable insight into the response of flatfish stocks to past and future climate changes in the eastern Bering Sea – a system that is especially vulnerable to warming. Close

• 31. [Article] Distribution, habitat use, and growth of juvenile Chinook salmon in the Metolius River Basin, Oregon

  Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at ...

  Citation × Citation Citation Abstract Copy Title: Distribution, habitat use, and growth of juvenile Chinook salmon in the Metolius River Basin, Oregon Author: Lovtang, Jens C. Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at the Pelton Round Butte Hydroelectric Project on the Deschutes River. Plans have been developed to reestablish passage of anadromous fish through the Project. However, only anecdotal evidence exists on the historic distribution of spring Chinook juveniles in the Basin. A recent approach to characterizing habitat quality for anadromous fishes in the Basin was the development of HabRate (Burke et al. In Press), which presented a relative quality rating of habitat based upon published fish-habitat relationships at the stream reach spatial scale. The present study was initiated to test the predictions of HabRate for summer rearing juvenile Chinook salmon in the Metolius Basin. Chinook salmon fry were released in the winters of 2002 and 2003, and their densities and sizes were quantified via snorkeling and fish collection in six unique study reaches in the upper Metolius River Basin. Each of these stream reaches varied in terms of temperature, habitat availability, invertebrate drift availability, and fish community composition. My observations were not consistent with the qualitative predictions of HabRate. Moreover, habitat utilization was not consistent among study reaches. Similar to other qualitative habitat rating models (e.g. Habitat Suitability Indices (Raleigh et al. 1986) and Instream Flow Incremental Methodology (Bovee 1982)), HabRate's predictions rely solely on physical habitat characteristics, with the assumption that habitat will be used consistently among stream reaches (i.e. a pool in one reach is of equal importance as a pool in another reach). My results suggest that the unique ecological setting of each study reach provides the context for understanding the patterns of growth, habitat use, and diurnal activity of juvenile Chinook salmon. The inclusion of ecological components, such as food availability, the bioenergetic constraints of temperature, and the risk of predation can make these models more biologically realistic. Growth of juvenile Chinook salmon among study reaches had a curvilinear relationship to water temperature, and was also positively related to the drift density of invertebrate biomass. In three collection seasons (fall 2002, spring 2003 and fall 2003) 41 to 69% of the variations in fork lengths were explained by a multiple regression model including temperature and invertebrate drift. Based on these findings, I present a conceptual growth capacity model based on the tenets of bioenergetics as a basis for understanding the relative quality of the habitat among stream reaches for juvenile Chinook salmon. Fish community composition can help to explain observed patterns in habitat utilization and diel activity patterns. In the study reaches that had a greater presence of adult trout (potential predators), observations of juvenile Chinook salmon in mid-channel habitat were infrequent to non-existent during the day and abundances were higher in all habitat types at night. In the study reaches with colder water temperatures, observed juvenile Chinook salmon densities were higher at night. I suggest that habitat selection and diurnal activity patterns in some study reaches are reflective of strategies taken by the fish to minimize risks of predation. Title: Distribution, habitat use, and growth of juvenile Chinook salmon in the Metolius River Basin, Oregon Author: Lovtang, Jens C. Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at the Pelton Round Butte Hydroelectric Project on the Deschutes River. Plans have been developed to reestablish passage of anadromous fish through the Project. However, only anecdotal evidence exists on the historic distribution of spring Chinook juveniles in the Basin. A recent approach to characterizing habitat quality for anadromous fishes in the Basin was the development of HabRate (Burke et al. In Press), which presented a relative quality rating of habitat based upon published fish-habitat relationships at the stream reach spatial scale. The present study was initiated to test the predictions of HabRate for summer rearing juvenile Chinook salmon in the Metolius Basin. Chinook salmon fry were released in the winters of 2002 and 2003, and their densities and sizes were quantified via snorkeling and fish collection in six unique study reaches in the upper Metolius River Basin. Each of these stream reaches varied in terms of temperature, habitat availability, invertebrate drift availability, and fish community composition. My observations were not consistent with the qualitative predictions of HabRate. Moreover, habitat utilization was not consistent among study reaches. Similar to other qualitative habitat rating models (e.g. Habitat Suitability Indices (Raleigh et al. 1986) and Instream Flow Incremental Methodology (Bovee 1982)), HabRate's predictions rely solely on physical habitat characteristics, with the assumption that habitat will be used consistently among stream reaches (i.e. a pool in one reach is of equal importance as a pool in another reach). My results suggest that the unique ecological setting of each study reach provides the context for understanding the patterns of growth, habitat use, and diurnal activity of juvenile Chinook salmon. The inclusion of ecological components, such as food availability, the bioenergetic constraints of temperature, and the risk of predation can make these models more biologically realistic. Growth of juvenile Chinook salmon among study reaches had a curvilinear relationship to water temperature, and was also positively related to the drift density of invertebrate biomass. In three collection seasons (fall 2002, spring 2003 and fall 2003) 41 to 69% of the variations in fork lengths were explained by a multiple regression model including temperature and invertebrate drift. Based on these findings, I present a conceptual growth capacity model based on the tenets of bioenergetics as a basis for understanding the relative quality of the habitat among stream reaches for juvenile Chinook salmon. Fish community composition can help to explain observed patterns in habitat utilization and diel activity patterns. In the study reaches that had a greater presence of adult trout (potential predators), observations of juvenile Chinook salmon in mid-channel habitat were infrequent to non-existent during the day and abundances were higher in all habitat types at night. In the study reaches with colder water temperatures, observed juvenile Chinook salmon densities were higher at night. I suggest that habitat selection and diurnal activity patterns in some study reaches are reflective of strategies taken by the fish to minimize risks of predation. Close

• 32. [Article] Seasonal distribution and environment of adult Pacific herring (Clupea harengus pallasi) near Auke Bay, Lynn Canal, southeastern Alaska

  The distribution of adult Pacific herring (Clupea harengue pallasi) near Auke Bay, Lynn Canal, southeastern Alaska, varied by depth and geographic area over 24 successive months during 1973-75. From June ...

  Citation × Citation Citation Abstract Copy Title: Seasonal distribution and environment of adult Pacific herring (Clupea harengus pallasi) near Auke Bay, Lynn Canal, southeastern Alaska Author: Carlson, Harry Richard The distribution of adult Pacific herring (Clupea harengue pallasi) near Auke Bay, Lynn Canal, southeastern Alaska, varied by depth and geographic area over 24 successive months during 1973-75. From June through September, schools concentrated at 5- to 37-m depths where zooplankton was abundant, and moderate currents were present in a stratified water column. The schools migrated from this area to wintering grounds in October when windstorms and sinking of cooling surface waters broke up stratification, day length shortened, and food abundance declined drastically. The schools remained near bottom in the deeper parts of the wintering grounds at 52- to 85-m depths into February or March when day length had increased, but temperatures and food abundance remained low. At this time, the herring left the wintering grounds and moved up Lynn Canal to areas near spawning beaches. Pacific herring remained in these areas until water temperatures increased and plankton blooms appeared in late April and May, at which time the fish moved into the shallows and spawned. By early summer, the schools gradually concentrated again on the main feeding grounds. An evaluation of the study design and potential for improvements in similar studies is included. Title: Seasonal distribution and environment of adult Pacific herring (Clupea harengus pallasi) near Auke Bay, Lynn Canal, southeastern Alaska Author: Carlson, Harry Richard The distribution of adult Pacific herring (Clupea harengue pallasi) near Auke Bay, Lynn Canal, southeastern Alaska, varied by depth and geographic area over 24 successive months during 1973-75. From June through September, schools concentrated at 5- to 37-m depths where zooplankton was abundant, and moderate currents were present in a stratified water column. The schools migrated from this area to wintering grounds in October when windstorms and sinking of cooling surface waters broke up stratification, day length shortened, and food abundance declined drastically. The schools remained near bottom in the deeper parts of the wintering grounds at 52- to 85-m depths into February or March when day length had increased, but temperatures and food abundance remained low. At this time, the herring left the wintering grounds and moved up Lynn Canal to areas near spawning beaches. Pacific herring remained in these areas until water temperatures increased and plankton blooms appeared in late April and May, at which time the fish moved into the shallows and spawned. By early summer, the schools gradually concentrated again on the main feeding grounds. An evaluation of the study design and potential for improvements in similar studies is included. Close

• 33. [Article] Progress report, Yaquina Bay oyster investigation

  Unpublished manuscript that was distributed locally and is cited in contemporary publications. Describes oyster grounds, gives a brief history of the oyster industry in Yaquina Bay, reports on current ...

  Citation × Citation Citation Abstract Copy Title: Progress report, Yaquina Bay oyster investigation Author: U. S. Bureau of Fisheries, McMillin, Harvey C. Unpublished manuscript that was distributed locally and is cited in contemporary publications. Describes oyster grounds, gives a brief history of the oyster industry in Yaquina Bay, reports on current conditions. Tables show salinity of Yaquina Bay for May-August, 1931 and 1931 spawning season. Recommends expanding production on State-owned beds. Title: Progress report, Yaquina Bay oyster investigation Author: U. S. Bureau of Fisheries, McMillin, Harvey C. Unpublished manuscript that was distributed locally and is cited in contemporary publications. Describes oyster grounds, gives a brief history of the oyster industry in Yaquina Bay, reports on current conditions. Tables show salinity of Yaquina Bay for May-August, 1931 and 1931 spawning season. Recommends expanding production on State-owned beds. Close

• 34. [Article] Effects of the 1997-1998 El Niño on early-juvenile Pacific hake Merluccius productus: age, growth, abundance, and diet in coastal nursery habitats

  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: Effects of the 1997-1998 El Niño on early-juvenile Pacific hake Merluccius productus: age, growth, abundance, and diet in coastal nursery habitats Author: Grover, Jill J., Woodbury, David, Buckley, Troy W. 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: Effects of the 1997-1998 El Niño on early-juvenile Pacific hake Merluccius productus: age, growth, abundance, and diet in coastal nursery habitats Author: Grover, Jill J., Woodbury, David, Buckley, Troy W. 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

• 35. [Article] Aspects of the foraging ecology of humpback whales (Megaptera novaeangliae) in Frederick Sound and Stephens Passage, Southeast Alaska

  The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales ...

  Citation × Citation Citation Abstract Copy Title: Aspects of the foraging ecology of humpback whales (Megaptera novaeangliae) in Frederick Sound and Stephens Passage, Southeast Alaska Author: Szabo, Andrew, 1974- The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales than estimated for the entire North Pacific several decades ago. An understanding of how this growing population is repopulating traditional foraging grounds will benefit from detailed investigations of their prey preferences and trends in whale abundance and distribution relative to those prey. This dissertation examines these issues from late May until early September 2008 in Frederick Sound and Stephens Passage, a Southeast Alaskan feeding area historically used by humpback whales. The foundation for the study is an analysis of the life histories and abundance patterns of euphausiids, the principal prey of humpbacks in the area, during late spring and summer. Four species, Thysanoessa raschii, T. longipes, T. spinifera, and Euphausia pacifica, were identified in plankton net samples collected at random locations throughout the study site (n = 49) and in locations where a strong scattering layer was observed on a 120 kHz echosounder (n = 48). Both sample types varied in euphausiid species composition. Abundance patterns of immature euphausiids coupled with observations of females carrying spermatophores indicated differences between species in spawning schedules. Thysanoessa spp. began spawning in early April with the spring phytoplankton bloom and continued until late June, whereas E. pacifica began spawning in early June and continued until late August. This protracted recruitment of immature euphausiids was geographically widespread throughout the summer in contrast to adults, which, although present all summer, were found primarily in slope and shallow (< 100 m) areas. To determine if humpback whales preferred one euphausiid species or life-stage over another, net sample and hydroacoustic data collected in the vicinity of whales were compared to similar data collected in random locations throughout the study site. This revealed that whales targeted dense aggregations of adult euphausiids, but did not discriminate between the various species, which was surprising because of presumed differences in the energy density linked to their different spawning schedules. Additionally, whales did not spend time in areas with concentrations of immature euphausiids, which were likely not large enough during the study period to be suitable prey. With this preference for adult euphausiids, the abundance and distribution patterns of humpbacks were examined in relation to prey availability. Whale abundance was lowest at the beginning of the study in late May at ca. 68 whales and peaked in late July at ca. 228 animals – approximately 12% of the region’s estimated abundance for the study year. This study did not detect a concomitant increase in the availability of adult euphausiids, which is unsurprising since immature euphausiids would not recruit into the adult population until after the end of the study, and post-spawning mortality and predation pressure is presumably high during this time. Instead, whales clustered increasingly around comparatively fewer prey as the summer progressed. These observations, combined with a plateau in whale abundance after July, suggest that their abundance in the area was limited by euphausiid availability. Estimates of whales using the study site during the summer have remained similar over several decades despite a dramatic increase in humpback numbers in Southeast Alaska and elsewhere in the North Pacific. The results from this study suggest that, although the study site remains important seasonally to some whales, it is not a significant source of prey responsible for regional population growth in general. More likely, it is part of a network of feeding areas that has influenced the population trend. Further insight into these and the other issues raised in this dissertation could come from several additional analyses. An extended sampling season that captures the recruitment of immature euphausiids into the adult population would reveal whether a given year's prey cohort represents an important resource to whales in that same year, which has potential implications for interpreting mid-late season whale abundance patterns. As well, a photo-identification study would be useful in characterizing whale residency patterns and determining whether the abundance trends reflect a relatively small subset of the regional population using the area for most of the season or a continuous flow of a larger portion of the population. Finally, similar analyses as those outlined here but conducted in other areas within the region would provide additional insight into the network’s capacity to support the recovering whale population. Title: Aspects of the foraging ecology of humpback whales (Megaptera novaeangliae) in Frederick Sound and Stephens Passage, Southeast Alaska Author: Szabo, Andrew, 1974- The North Pacific humpback whale (Megaptera novaeangliae) population has been increasing at an average annual rate of ~6% since the early 1990s. In northern Southeast Alaska alone, there are now more whales than estimated for the entire North Pacific several decades ago. An understanding of how this growing population is repopulating traditional foraging grounds will benefit from detailed investigations of their prey preferences and trends in whale abundance and distribution relative to those prey. This dissertation examines these issues from late May until early September 2008 in Frederick Sound and Stephens Passage, a Southeast Alaskan feeding area historically used by humpback whales. The foundation for the study is an analysis of the life histories and abundance patterns of euphausiids, the principal prey of humpbacks in the area, during late spring and summer. Four species, Thysanoessa raschii, T. longipes, T. spinifera, and Euphausia pacifica, were identified in plankton net samples collected at random locations throughout the study site (n = 49) and in locations where a strong scattering layer was observed on a 120 kHz echosounder (n = 48). Both sample types varied in euphausiid species composition. Abundance patterns of immature euphausiids coupled with observations of females carrying spermatophores indicated differences between species in spawning schedules. Thysanoessa spp. began spawning in early April with the spring phytoplankton bloom and continued until late June, whereas E. pacifica began spawning in early June and continued until late August. This protracted recruitment of immature euphausiids was geographically widespread throughout the summer in contrast to adults, which, although present all summer, were found primarily in slope and shallow (< 100 m) areas. To determine if humpback whales preferred one euphausiid species or life-stage over another, net sample and hydroacoustic data collected in the vicinity of whales were compared to similar data collected in random locations throughout the study site. This revealed that whales targeted dense aggregations of adult euphausiids, but did not discriminate between the various species, which was surprising because of presumed differences in the energy density linked to their different spawning schedules. Additionally, whales did not spend time in areas with concentrations of immature euphausiids, which were likely not large enough during the study period to be suitable prey. With this preference for adult euphausiids, the abundance and distribution patterns of humpbacks were examined in relation to prey availability. Whale abundance was lowest at the beginning of the study in late May at ca. 68 whales and peaked in late July at ca. 228 animals – approximately 12% of the region’s estimated abundance for the study year. This study did not detect a concomitant increase in the availability of adult euphausiids, which is unsurprising since immature euphausiids would not recruit into the adult population until after the end of the study, and post-spawning mortality and predation pressure is presumably high during this time. Instead, whales clustered increasingly around comparatively fewer prey as the summer progressed. These observations, combined with a plateau in whale abundance after July, suggest that their abundance in the area was limited by euphausiid availability. Estimates of whales using the study site during the summer have remained similar over several decades despite a dramatic increase in humpback numbers in Southeast Alaska and elsewhere in the North Pacific. The results from this study suggest that, although the study site remains important seasonally to some whales, it is not a significant source of prey responsible for regional population growth in general. More likely, it is part of a network of feeding areas that has influenced the population trend. Further insight into these and the other issues raised in this dissertation could come from several additional analyses. An extended sampling season that captures the recruitment of immature euphausiids into the adult population would reveal whether a given year's prey cohort represents an important resource to whales in that same year, which has potential implications for interpreting mid-late season whale abundance patterns. As well, a photo-identification study would be useful in characterizing whale residency patterns and determining whether the abundance trends reflect a relatively small subset of the regional population using the area for most of the season or a continuous flow of a larger portion of the population. Finally, similar analyses as those outlined here but conducted in other areas within the region would provide additional insight into the network’s capacity to support the recovering whale population. Close

• 36. [Article] GIS modeling of potential marine protected areas in the Northwest Atlantic via biological and socioeconomic parameters

  Overfishing of our national marine resources has degraded some of the most productive fishing regions in the Northwest Atlantic Ocean, most notably the Gulf of Maine and Georges Bank. These regions may ...

  Citation × Citation Citation Abstract Copy Title: GIS modeling of potential marine protected areas in the Northwest Atlantic via biological and socioeconomic parameters Author: Keith, Charles M. Overfishing of our national marine resources has degraded some of the most productive fishing regions in the Northwest Atlantic Ocean, most notably the Gulf of Maine and Georges Bank. These regions may have shifted from productive trophic regimes to a less than optimal state therefore reducing fishers’ catches and associated revenue from commercially targeted species (Sinclair and Murawski, 1997, Jennings et al, 2001). Marine protected areas (MPAs) have been offered as an effective management tool to preserve biodiversity, enhance commercial fisheries, and protect against poor decisions in fisheries management (Bohnsack, 1999). Geographic information systems (GIS) bring together the fields of geography and fisheries management to help build a better understanding of the spatial interactions of complex marine environments (e.g., Kracker, 1999). Using GIS and spatial management such as MPAs can help fishery managers conserve and improve the population status of important biological resources while helping to preserve commercial fishing, an important social and political industry in New England. Incorporating the needs of stakeholders in management decisions is necessary in order to implement an effective fisheries management strategy (e.g., Malakoff, 2002). This study used a weighted optimization raster model in a GIS to compare biological significant regions, which were composed of biodiversity estimates and spawning and juvenile habitats, to important commercial fishing grounds in the Gulf of Maine and Georges Bank. Biodiversity, spawning and juvenile data values were derived from fishery independent data collected by 2 the National Marine Fisheries Service in Woods Hole, MA. The essential commercial fishing zones were created from Vessel Trip Reports, which are derived directly from reports sent in by federally permitted fishers. The weighted model compares the biologically important resources from an area, or cell, to the level of commercial fishing occurring in the same cell using simple mathematically algorithms in map algebra. The model output shows where placement of MPAs might be most beneficial in order to conserve marine resources and enhance fisheries, as well as areas where fishing is more suitable. Output can be viewed in multiple ways, a spectrum of values ranging from negative numbers to positive ones or simply as areas important for the fishing community or potential MPA. The more negative the value in the spectrum output then the more important the area would be for fishers and conversely the more positive the output then the more suitable the area would be for possible MPA designation. The optimization model can be tuned to meet management goals and objectives by adjusting the weighting scenarios for the input variables. The model design can be used for multiple species and ecosystem management or to protect specifically targeted species of particular concern. Managers may use the output to delineate MPAs in a variety of ways depending on the conditions of the resources and the prospects of the fishing community. Managers will enjoy greater success as the needs of both fishers and biological resources are met. Title: GIS modeling of potential marine protected areas in the Northwest Atlantic via biological and socioeconomic parameters Author: Keith, Charles M. Overfishing of our national marine resources has degraded some of the most productive fishing regions in the Northwest Atlantic Ocean, most notably the Gulf of Maine and Georges Bank. These regions may have shifted from productive trophic regimes to a less than optimal state therefore reducing fishers’ catches and associated revenue from commercially targeted species (Sinclair and Murawski, 1997, Jennings et al, 2001). Marine protected areas (MPAs) have been offered as an effective management tool to preserve biodiversity, enhance commercial fisheries, and protect against poor decisions in fisheries management (Bohnsack, 1999). Geographic information systems (GIS) bring together the fields of geography and fisheries management to help build a better understanding of the spatial interactions of complex marine environments (e.g., Kracker, 1999). Using GIS and spatial management such as MPAs can help fishery managers conserve and improve the population status of important biological resources while helping to preserve commercial fishing, an important social and political industry in New England. Incorporating the needs of stakeholders in management decisions is necessary in order to implement an effective fisheries management strategy (e.g., Malakoff, 2002). This study used a weighted optimization raster model in a GIS to compare biological significant regions, which were composed of biodiversity estimates and spawning and juvenile habitats, to important commercial fishing grounds in the Gulf of Maine and Georges Bank. Biodiversity, spawning and juvenile data values were derived from fishery independent data collected by 2 the National Marine Fisheries Service in Woods Hole, MA. The essential commercial fishing zones were created from Vessel Trip Reports, which are derived directly from reports sent in by federally permitted fishers. The weighted model compares the biologically important resources from an area, or cell, to the level of commercial fishing occurring in the same cell using simple mathematically algorithms in map algebra. The model output shows where placement of MPAs might be most beneficial in order to conserve marine resources and enhance fisheries, as well as areas where fishing is more suitable. Output can be viewed in multiple ways, a spectrum of values ranging from negative numbers to positive ones or simply as areas important for the fishing community or potential MPA. The more negative the value in the spectrum output then the more important the area would be for fishers and conversely the more positive the output then the more suitable the area would be for possible MPA designation. The optimization model can be tuned to meet management goals and objectives by adjusting the weighting scenarios for the input variables. The model design can be used for multiple species and ecosystem management or to protect specifically targeted species of particular concern. Managers may use the output to delineate MPAs in a variety of ways depending on the conditions of the resources and the prospects of the fishing community. Managers will enjoy greater success as the needs of both fishers and biological resources are met. Close

• 37. [Article] Using parasite community data and population genetics for assessing Pacific sardine (Sardinops sagax) population structure along the west coast of North America

  Pacific sardines (Sardinops sagax) are an economically and ecologically important forage fish which transfer energy from planktonic primary producers and secondary consumers to upper trophic predators. ...

  Citation × Citation Citation Abstract Copy Title: Using parasite community data and population genetics for assessing Pacific sardine (Sardinops sagax) population structure along the west coast of North America Author: Baldwin, Rebecca E. B. Pacific sardines (Sardinops sagax) are an economically and ecologically important forage fish which transfer energy from planktonic primary producers and secondary consumers to upper trophic predators. Previous genetics studies of Pacific sardine suggested a panmictic population with a shallow genetic structure. However, more than one subpopulation within the Central California Offshore management unit may exist based on recovering larger individuals at higher latitudes and a temporal difference in sardine spawning off Southern California and the Pacific Northwest. Potential for separate sardine subpopulations questions the long-standing paradigm of an annual migration of individuals to feeding grounds off the Pacific Northwest in the summer with migrants returning to Southern California in the fall to spawn the following spring. This study applied parasite community analyses and population genetics techniques to assess migration patterns and stock structure of Pacific sardine in the California Current from Vancouver Island, British Columbia, Canada to San Diego, California, USA. A coastwide sardine migration is supported by the geographical distribution of Myosaccium ecaude (Trematoda), but a second migration pattern was identified within the Pacific Northwest from the geographic distribution of Lecithaster gibbosus (Trematoda). Population genetics studies identified a panmictic distribution for: 1) the trematode M. ecaude using a 283bp portion of the NADH-dehydrogenase subunit 1 (ND1) mitochondrial DNA (mtDNA) gene; and 2) three species of Anisakis nematodes (A. simplex s.s., A. pegreffii, and A. simplex 'C') using a 524bp portion of the cytochrome c oxidase 2 (cox2) mtDNA gene. These results suggest that the extensive movement of all of the potential hosts utilized by these parasites, the limited oceanographic barriers, and complexity in the California Current are not preventing the mixing of M. ecaude or Anisakis species populations. The diversity and availability of fish and cetacean species that undergo extensive migrations along the full length of the California Current system may enable large geographically distributed population sizes of these parasite species. We thus cannot confirm the existence of separate Pacific sardine subpopulations within the California Current by the occurrence of parasite communities or the population genetics analyses of M. ecaude or the three Anisakis species. Title: Using parasite community data and population genetics for assessing Pacific sardine (Sardinops sagax) population structure along the west coast of North America Author: Baldwin, Rebecca E. B. Pacific sardines (Sardinops sagax) are an economically and ecologically important forage fish which transfer energy from planktonic primary producers and secondary consumers to upper trophic predators. Previous genetics studies of Pacific sardine suggested a panmictic population with a shallow genetic structure. However, more than one subpopulation within the Central California Offshore management unit may exist based on recovering larger individuals at higher latitudes and a temporal difference in sardine spawning off Southern California and the Pacific Northwest. Potential for separate sardine subpopulations questions the long-standing paradigm of an annual migration of individuals to feeding grounds off the Pacific Northwest in the summer with migrants returning to Southern California in the fall to spawn the following spring. This study applied parasite community analyses and population genetics techniques to assess migration patterns and stock structure of Pacific sardine in the California Current from Vancouver Island, British Columbia, Canada to San Diego, California, USA. A coastwide sardine migration is supported by the geographical distribution of Myosaccium ecaude (Trematoda), but a second migration pattern was identified within the Pacific Northwest from the geographic distribution of Lecithaster gibbosus (Trematoda). Population genetics studies identified a panmictic distribution for: 1) the trematode M. ecaude using a 283bp portion of the NADH-dehydrogenase subunit 1 (ND1) mitochondrial DNA (mtDNA) gene; and 2) three species of Anisakis nematodes (A. simplex s.s., A. pegreffii, and A. simplex 'C') using a 524bp portion of the cytochrome c oxidase 2 (cox2) mtDNA gene. These results suggest that the extensive movement of all of the potential hosts utilized by these parasites, the limited oceanographic barriers, and complexity in the California Current are not preventing the mixing of M. ecaude or Anisakis species populations. The diversity and availability of fish and cetacean species that undergo extensive migrations along the full length of the California Current system may enable large geographically distributed population sizes of these parasite species. We thus cannot confirm the existence of separate Pacific sardine subpopulations within the California Current by the occurrence of parasite communities or the population genetics analyses of M. ecaude or the three Anisakis species. Close

• 38. [Article] Natural history and ecology of larval Lost River suckers and larval shortnose suckers in the Williamson River-Upper Klamath Lake System

  We monitored larval Lost River and shortnose suckers from natal beds in the Williamson and Sprague rivers to nursery grounds in Upper Klamath Lake. Downstream movements occurred at night, in the middle ...

  Citation × Citation Citation Abstract Copy Title: Natural history and ecology of larval Lost River suckers and larval shortnose suckers in the Williamson River-Upper Klamath Lake System Author: Cooperman, Michael S. We monitored larval Lost River and shortnose suckers from natal beds in the Williamson and Sprague rivers to nursery grounds in Upper Klamath Lake. Downstream movements occurred at night, in the middle of the channel, and on the falling limb of the hydrograph. Ages, sizes, and developmental stages of larvae from spawning beds and the river mouth were similar, while larvae collected contemporaneously from the lake tended to be larger and better fed. Our results indicate in-river rearing was rare, that a rapid outmigration to the lake was favorable for larval survival, and that modification of the lower Williamson River does not appear to have prohibited rapid entry or preclude access to Upper Klamath Lake. Within the Williamson River and Upper Klamath Lake, emergent macrophytes supported significantly higher abundance, larger mean sizes, and better fed larvae than submerged macrophytes, woody vegetation, or open water areas. Analysis of seven years of larval sucker production and survival corroborated the habitat analysis by identifying a positive relationship with emergent macrophyte availability as well as a positive relationship with air temperature and a negative relationship with high wind. These findings illustrate the importance of fast growth, appropriate habitat and calm hydrological conditions for larvae, and are highly consistent with other larval fish studies. Title: Natural history and ecology of larval Lost River suckers and larval shortnose suckers in the Williamson River-Upper Klamath Lake System Author: Cooperman, Michael S. We monitored larval Lost River and shortnose suckers from natal beds in the Williamson and Sprague rivers to nursery grounds in Upper Klamath Lake. Downstream movements occurred at night, in the middle of the channel, and on the falling limb of the hydrograph. Ages, sizes, and developmental stages of larvae from spawning beds and the river mouth were similar, while larvae collected contemporaneously from the lake tended to be larger and better fed. Our results indicate in-river rearing was rare, that a rapid outmigration to the lake was favorable for larval survival, and that modification of the lower Williamson River does not appear to have prohibited rapid entry or preclude access to Upper Klamath Lake. Within the Williamson River and Upper Klamath Lake, emergent macrophytes supported significantly higher abundance, larger mean sizes, and better fed larvae than submerged macrophytes, woody vegetation, or open water areas. Analysis of seven years of larval sucker production and survival corroborated the habitat analysis by identifying a positive relationship with emergent macrophyte availability as well as a positive relationship with air temperature and a negative relationship with high wind. These findings illustrate the importance of fast growth, appropriate habitat and calm hydrological conditions for larvae, and are highly consistent with other larval fish studies. Close

• 39. [Article] Developing a predator-prey model for the hake and blue whiting Spanish fisheries

  The aim of this work is to develop a predator-prey model for two species of commercial importance captured by the Spanish fishing fleet in the National Fishing Ground (ICES areas VIIIc and IXa). In this ...

  Citation × Citation Citation Abstract Copy Title: Developing a predator-prey model for the hake and blue whiting Spanish fisheries Author: Perez-Perez, Marcos, Varela-Lafuente, Manuel, Garza-Gil, Dolores, Torralba-Cano, Julia The aim of this work is to develop a predator-prey model for two species of commercial importance captured by the Spanish fishing fleet in the National Fishing Ground (ICES areas VIIIc and IXa). In this model, the Southern hake (Merluccius merluccius) represents the predator, and the blue whiting (Micromesistius poutassou) is the prey. Blue whiting is the hake’s main prey in the study area, and it represents about 40% of the Southern hake diet. Both the predator and prey population dynamics follow the Lotka-Volterra formulation, and population dynamics are assumed as logistic, with two interaction coefficients: α is the effect of a unit change in the prey on the percent growth rate of the predator and β is the attack rate or searching efficiency of the predator. The populations interact randomly in proportion to population density. Logistic predator-prey equations were applied to the Southern hake and blue whiting stocks, including biomass, intrinsic rates of growth, carrying capacity and capture for both species. The goal is to maximize the present value of profit, forming the current value Hamiltonian for the maximization problem. Capture costs and prices of hake and blue whiting and discount rate were introduced at this point. Landings and SSB (Spawning Stock Biomass) data from both stocks over the period 1988-2010 were used for an econometric estimation by means of the Ordinary Least Squares method, to determine the form taken by the predator-prey net growth functions. Title: Developing a predator-prey model for the hake and blue whiting Spanish fisheries Author: Perez-Perez, Marcos, Varela-Lafuente, Manuel, Garza-Gil, Dolores, Torralba-Cano, Julia The aim of this work is to develop a predator-prey model for two species of commercial importance captured by the Spanish fishing fleet in the National Fishing Ground (ICES areas VIIIc and IXa). In this model, the Southern hake (Merluccius merluccius) represents the predator, and the blue whiting (Micromesistius poutassou) is the prey. Blue whiting is the hake’s main prey in the study area, and it represents about 40% of the Southern hake diet. Both the predator and prey population dynamics follow the Lotka-Volterra formulation, and population dynamics are assumed as logistic, with two interaction coefficients: α is the effect of a unit change in the prey on the percent growth rate of the predator and β is the attack rate or searching efficiency of the predator. The populations interact randomly in proportion to population density. Logistic predator-prey equations were applied to the Southern hake and blue whiting stocks, including biomass, intrinsic rates of growth, carrying capacity and capture for both species. The goal is to maximize the present value of profit, forming the current value Hamiltonian for the maximization problem. Capture costs and prices of hake and blue whiting and discount rate were introduced at this point. Landings and SSB (Spawning Stock Biomass) data from both stocks over the period 1988-2010 were used for an econometric estimation by means of the Ordinary Least Squares method, to determine the form taken by the predator-prey net growth functions. Close

• 40. [Article] Impacts of instream flows on the Colorado River Delta, Mexico : spatial vegetation change analysis and opportunities for restoration

  Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory ...

  Citation × Citation Citation Abstract Copy Title: Impacts of instream flows on the Colorado River Delta, Mexico : spatial vegetation change analysis and opportunities for restoration Author: Zamora-Arroyo, Jose Francisco Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory birds as well as spawning and protection habitat for many fish and other invertebrate species. However, the Delta's wetlands started to disappear as water was used for agricultural and urban uses in the United States and Mexico. The 1944 United States-Mexico water treaty, which allocates 1.8 million m³/year to Mexico, did not define a minimum flow to maintain the Delta's ecosystems. The resulting degraded Delta lead to the perception in the 1980s that the Delta was a dead ecosystem. This study investigates whether this "dead Delta" perception is valid. Its central hypothesis is that regenerated vegetation in riparian and flood plain zones is associated with surplus river flows during the 1990s. A vegetation analysis, using satellite imagery and field methods, shows that native trees have regenerated during the last 20 years, and now account for 23% of vegetation in a 100 km, non-perennial, stretch of river below the United States-Mexico border. A spatial trend analysis using multi-temporal data on percent vegetation cover indicates that there are 6,320 hectares that show a significant increasing trend (p-value<0.05) in vegetation cover, with the Delta's riparian zone having at least 18% of its area showing this trend. The study estimates that once in four years February to April flow of 300 million m³ (at 80-120 m³/s) is sufficient to germinate and establish new cohorts of native trees, and highlights the need for smaller but more periodic flows in order to maintain wetland areas. It is concluded that there is clear evidence of the resilience of the Delta's ecosystems and that the "dead Delta" perception is no longer valid. There exist critical habitat in the Delta that needs to be protected, while there also exist short and long term opportunities to ecologically enhance and expand current habitat. Hydrological and ecological studies are needed to estimate specific water requirements for these areas in order to efficiently target them for immediate and long term conservation actions. Title: Impacts of instream flows on the Colorado River Delta, Mexico : spatial vegetation change analysis and opportunities for restoration Author: Zamora-Arroyo, Jose Francisco Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory birds as well as spawning and protection habitat for many fish and other invertebrate species. However, the Delta's wetlands started to disappear as water was used for agricultural and urban uses in the United States and Mexico. The 1944 United States-Mexico water treaty, which allocates 1.8 million m³/year to Mexico, did not define a minimum flow to maintain the Delta's ecosystems. The resulting degraded Delta lead to the perception in the 1980s that the Delta was a dead ecosystem. This study investigates whether this "dead Delta" perception is valid. Its central hypothesis is that regenerated vegetation in riparian and flood plain zones is associated with surplus river flows during the 1990s. A vegetation analysis, using satellite imagery and field methods, shows that native trees have regenerated during the last 20 years, and now account for 23% of vegetation in a 100 km, non-perennial, stretch of river below the United States-Mexico border. A spatial trend analysis using multi-temporal data on percent vegetation cover indicates that there are 6,320 hectares that show a significant increasing trend (p-value<0.05) in vegetation cover, with the Delta's riparian zone having at least 18% of its area showing this trend. The study estimates that once in four years February to April flow of 300 million m³ (at 80-120 m³/s) is sufficient to germinate and establish new cohorts of native trees, and highlights the need for smaller but more periodic flows in order to maintain wetland areas. It is concluded that there is clear evidence of the resilience of the Delta's ecosystems and that the "dead Delta" perception is no longer valid. There exist critical habitat in the Delta that needs to be protected, while there also exist short and long term opportunities to ecologically enhance and expand current habitat. Hydrological and ecological studies are needed to estimate specific water requirements for these areas in order to efficiently target them for immediate and long term conservation actions. Close

• 41. [Article] Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon

  Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile ...

  Citation × Citation Citation Abstract Copy Title: Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon Author: Mackereth, Kailan F. Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile salmonids providing them with food, winter shelter, and a transition zone between freshwater and saltwater. Lowland areas have undergone anthropogenic alterations (e.g., installation of tide gates, construction of dikes, channelization) to increase the net area of land suitable for agriculture and development resulting in watershed fragmentation and reduction in the amount of habitats with high intrinsic potential to support populations of juvenile salmonids. Until recent years, sub-yearling coho salmon found in lowland riverine habitats and estuarine marshes were assumed to have been displaced from optimal upland reaches by competition and high water discharge. Recent studies have concluded that early estuarine migrant behavior is volitional and these fish return as 20-40% of the spawning population, but there are few studies that delve into the capacity of estuarine habitat to support early estuarine life history strategies in systems heavily altered by human practices. This study documented differences in diet and condition factor (K) between sub-yearling and yearling coho salmon foraging concurrently in brackish or freshwater lowland habitat of the upper estuarine intertidal zone. Fish stomach contents were sampled by means of gastric lavage in three coastal lowland creeks in Coos Bay on the southern Oregon coast. Prey found in the samples were sorted, counted, identified, and dried to obtain dry weight biomass. Condition factor (K) and total dry weight prey biomass of fishes were not different between brackish and freshwater habitat; however, non-metric multidimensional scaling indicated that prey composition was substantially different between habitat and age class. These findings suggest that early migrating sub-yearlings and yearling smolts diverge in their diets whether they occupy the same or different habitats in the stream to estuary transition zone. Insects were important prey within the diets of yearling and sub-yearling freshwater foragers and sub-yearling brackish water foragers while crustaceans were important in the diets of yearling brackish water foragers. Future research exploring prey abundance and availability in relation to prey selected by juvenile coho salmon would denote habitat foraging quality and habitat exploitation by early estuarine migrants. Expanding this research to contrast natural intertidal habitats with those regulated by tide gates would be beneficial towards understanding the impact different styles of tide gates have on biotic communities and hydrological attributes (e.g., flow, chemistry, temperature, tidal exchange). Identification of factors that influence habitat selection in the stream-estuary ecotone by alternative early life history strategies of juvenile coho salmon is essential towards enhancing genetic diversity thereby strengthening the resiliency of the population. Title: Juvenile Coho Salmon (Oncorhynchus kisutch) Diet in Brackish and Freshwater Habitats in the Stream-estuary Ecotones of Coos Bay, Oregon Author: Mackereth, Kailan F. Loss of lowland estuarine and freshwater off-channel habitats along the Pacific Northwest coast has contributed to the decline of salmonid populations. These habitats serve as nursery grounds for juvenile salmonids providing them with food, winter shelter, and a transition zone between freshwater and saltwater. Lowland areas have undergone anthropogenic alterations (e.g., installation of tide gates, construction of dikes, channelization) to increase the net area of land suitable for agriculture and development resulting in watershed fragmentation and reduction in the amount of habitats with high intrinsic potential to support populations of juvenile salmonids. Until recent years, sub-yearling coho salmon found in lowland riverine habitats and estuarine marshes were assumed to have been displaced from optimal upland reaches by competition and high water discharge. Recent studies have concluded that early estuarine migrant behavior is volitional and these fish return as 20-40% of the spawning population, but there are few studies that delve into the capacity of estuarine habitat to support early estuarine life history strategies in systems heavily altered by human practices. This study documented differences in diet and condition factor (K) between sub-yearling and yearling coho salmon foraging concurrently in brackish or freshwater lowland habitat of the upper estuarine intertidal zone. Fish stomach contents were sampled by means of gastric lavage in three coastal lowland creeks in Coos Bay on the southern Oregon coast. Prey found in the samples were sorted, counted, identified, and dried to obtain dry weight biomass. Condition factor (K) and total dry weight prey biomass of fishes were not different between brackish and freshwater habitat; however, non-metric multidimensional scaling indicated that prey composition was substantially different between habitat and age class. These findings suggest that early migrating sub-yearlings and yearling smolts diverge in their diets whether they occupy the same or different habitats in the stream to estuary transition zone. Insects were important prey within the diets of yearling and sub-yearling freshwater foragers and sub-yearling brackish water foragers while crustaceans were important in the diets of yearling brackish water foragers. Future research exploring prey abundance and availability in relation to prey selected by juvenile coho salmon would denote habitat foraging quality and habitat exploitation by early estuarine migrants. Expanding this research to contrast natural intertidal habitats with those regulated by tide gates would be beneficial towards understanding the impact different styles of tide gates have on biotic communities and hydrological attributes (e.g., flow, chemistry, temperature, tidal exchange). Identification of factors that influence habitat selection in the stream-estuary ecotone by alternative early life history strategies of juvenile coho salmon is essential towards enhancing genetic diversity thereby strengthening the resiliency of the population. Close

• 42. [Article] Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta

  The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late ...

  Citation × Citation Citation Abstract Copy Title: Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta Author: Maggiulli, Nicole Marie The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late 1970s. In an effort to alleviate mammalian predation, increase nest success, and avoid a listing under the U.S. Endangered Species Act, an artificial nest island (island) program was implemented on the western CRD in 1983. The installation of new islands on the CRD is the sole management action of the Pacific Flyway Council on the breeding grounds, but no comprehensive evaluation of the program has been published. I examined general trends in island use and nest success over time for three island types (donut islands, fiberglass floater islands, and sandbag islands) from 1984-2005. I used data from the island program to identify factors associated with dusky Canada goose nesting (hereafter, use) and nest success on islands from 1996-2005. I generated a series of candidate models and used logistic regression with model selection techniques to determine how variables representing pond characteristics, vegetative characteristics, interactions with conspecifics and larid species, the previous year’s island status, and the distance to predator corridors were associated with island use and nest success for each year. Use of islands by dusky geese nesting on the western CRD increased between 1987 and 2005 from a low of 10% in 1987 to 44% in 2005. There was annual variability in factors associated with island use; however, use of islands was most consistently and strongly associated with the previous year’s island status. The odds of a nest being placed on an island that contained a successful nest the previous year were 2.91 to 6.62 times greater than for islands not used the previous year. There was also evidence for an increased likelihood of island use further from shore and for islands with up to 55% aerial shrub cover and shrubs up to 1 m tall. Nest success was consistently high, indicating islands have long term potential for increasing dusky goose nest success on the Copper River Delta. Compared to island use, my analysis of nest success and habitat features resulted in many more competitive models (average 10 v. 2 per year) with fewer strong (95% confidence intervals for parameter estimates excluded zero) associations between explanatory variables and nest success. Explanatory variables representing vegetative characteristics, interactions with conspecifics and larid species, and the distance to predator corridors had a relatively low capacity to explain nest success on artificial islands. However, there was some evidence for an increased likelihood of nest success on islands further from shore with shorter shrubs. Lower variability in factors associated with island use is likely because factors associated with nest site selection are controlled by decisions of the nesting goose. The importance of previous year’s island status on island use likely reflects high site fidelity by breeding adult geese, with fidelity being higher for birds that have successful nests. Alternately, dusky geese use cues from the previous year’s nesting activity when prospecting for island nest sites. In contrast, nest success is dependent on a more complex combination of factors that vary within and among years outside the control of a nesting goose. Inter-annual variation in the timing and magnitude of eulachon (Thaleichthys pacificus) spawning runs on large sloughs of the CRD and prey-switching by important dusky goose nest predators may have considerable influence on dusky goose nest success on islands, similar to mainland- nesting dusky geese. The inability to control for eulachon presence and abundance may have confounded my analysis of habitat features important to nest success. Therefore, factors such as presence of alternate prey (and predator abundance) may be more important to dusky goose nest success on islands than habitat features. Current use of available nest islands is at a program high of 44% and nest success also remains high (63%); suggesting the artificial nest island program is valuable for dusky geese. However, the contribution of island-nesting dusky geese to the dusky goose population on the Copper River Delta is unclear. There is a need for a population model that incorporates all recent information on dusky goose reproductive ecology to determine if artificial nest islands can increase dusky goose population size, and if so, how many islands are needed. Title: Factors associated with dusky Canada goose nesting and nest success on artificial nest islands of the western Copper River Delta Author: Maggiulli, Nicole Marie The population of dusky Canada geese (Branta canadensis occidentalis; hereafter, dusky geese) nesting on the western Copper River Delta (CRD) in south- central Alaska has been in decline since the late 1970s. In an effort to alleviate mammalian predation, increase nest success, and avoid a listing under the U.S. Endangered Species Act, an artificial nest island (island) program was implemented on the western CRD in 1983. The installation of new islands on the CRD is the sole management action of the Pacific Flyway Council on the breeding grounds, but no comprehensive evaluation of the program has been published. I examined general trends in island use and nest success over time for three island types (donut islands, fiberglass floater islands, and sandbag islands) from 1984-2005. I used data from the island program to identify factors associated with dusky Canada goose nesting (hereafter, use) and nest success on islands from 1996-2005. I generated a series of candidate models and used logistic regression with model selection techniques to determine how variables representing pond characteristics, vegetative characteristics, interactions with conspecifics and larid species, the previous year’s island status, and the distance to predator corridors were associated with island use and nest success for each year. Use of islands by dusky geese nesting on the western CRD increased between 1987 and 2005 from a low of 10% in 1987 to 44% in 2005. There was annual variability in factors associated with island use; however, use of islands was most consistently and strongly associated with the previous year’s island status. The odds of a nest being placed on an island that contained a successful nest the previous year were 2.91 to 6.62 times greater than for islands not used the previous year. There was also evidence for an increased likelihood of island use further from shore and for islands with up to 55% aerial shrub cover and shrubs up to 1 m tall. Nest success was consistently high, indicating islands have long term potential for increasing dusky goose nest success on the Copper River Delta. Compared to island use, my analysis of nest success and habitat features resulted in many more competitive models (average 10 v. 2 per year) with fewer strong (95% confidence intervals for parameter estimates excluded zero) associations between explanatory variables and nest success. Explanatory variables representing vegetative characteristics, interactions with conspecifics and larid species, and the distance to predator corridors had a relatively low capacity to explain nest success on artificial islands. However, there was some evidence for an increased likelihood of nest success on islands further from shore with shorter shrubs. Lower variability in factors associated with island use is likely because factors associated with nest site selection are controlled by decisions of the nesting goose. The importance of previous year’s island status on island use likely reflects high site fidelity by breeding adult geese, with fidelity being higher for birds that have successful nests. Alternately, dusky geese use cues from the previous year’s nesting activity when prospecting for island nest sites. In contrast, nest success is dependent on a more complex combination of factors that vary within and among years outside the control of a nesting goose. Inter-annual variation in the timing and magnitude of eulachon (Thaleichthys pacificus) spawning runs on large sloughs of the CRD and prey-switching by important dusky goose nest predators may have considerable influence on dusky goose nest success on islands, similar to mainland- nesting dusky geese. The inability to control for eulachon presence and abundance may have confounded my analysis of habitat features important to nest success. Therefore, factors such as presence of alternate prey (and predator abundance) may be more important to dusky goose nest success on islands than habitat features. Current use of available nest islands is at a program high of 44% and nest success also remains high (63%); suggesting the artificial nest island program is valuable for dusky geese. However, the contribution of island-nesting dusky geese to the dusky goose population on the Copper River Delta is unclear. There is a need for a population model that incorporates all recent information on dusky goose reproductive ecology to determine if artificial nest islands can increase dusky goose population size, and if so, how many islands are needed. Close