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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] 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

• 3. [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

• 4. [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

• 5. [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

• 6. [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

• 7. [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

• 8. [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

• 9. [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

• 10. [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