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• 71. [Article] Antarctic icebergs: A significant natural ocean sound source in the Southern Hemisphere

  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: Antarctic icebergs: A significant natural ocean sound source in the Southern Hemisphere Author: Lau, T. -K. A., Fowler, Matt, Matsumoto, Haru, Salo, Sigrid A., Dziak, Robert P., Haxel, Joseph H., Tournadre, Jean, Bohnenstiehl, DelWayne R. 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 the American Geophysical Union. The published article can be found at: http://agupubs.onlinelibrary.wiley.com/agu/journal/10.1002/%28ISSN%291525-2027/. Title: Antarctic icebergs: A significant natural ocean sound source in the Southern Hemisphere Author: Lau, T. -K. A., Fowler, Matt, Matsumoto, Haru, Salo, Sigrid A., Dziak, Robert P., Haxel, Joseph H., Tournadre, Jean, Bohnenstiehl, DelWayne R. 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 the American Geophysical Union. The published article can be found at: http://agupubs.onlinelibrary.wiley.com/agu/journal/10.1002/%28ISSN%291525-2027/. Close

• 72. [Article] Is Fishing Compatible with Environmental Conservation: A Stochastic Model with an Element of Self-Protection

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Is Fishing Compatible with Environmental Conservation: A Stochastic Model with an Element of Self-Protection Author: Hilgert, Nadine, Pardo, Sophie, Tidball, Mabel, Ami, Dominique Research Paper Title: Is Fishing Compatible with Environmental Conservation: A Stochastic Model with an Element of Self-Protection Author: Hilgert, Nadine, Pardo, Sophie, Tidball, Mabel, Ami, Dominique Research Paper Close

• 73. [Article] Long-Term Exposure to Fluoxetine Reduces Growth and Reproductive Potential in the Dominant Rocky Intertidal Mussel, Mytilus californianus

  Environmental stressors shape community composition and ecosystem functioning. Contaminants such as pharmaceuticals are of increasing concern as an environmental stressor due to their persistence in surface ...

  Citation × Citation Citation Abstract Copy Title: Long-Term Exposure to Fluoxetine Reduces Growth and Reproductive Potential in the Dominant Rocky Intertidal Mussel, Mytilus californianus Author: Peters, Joseph R., Granek, Elise F. Year: 2016 Environmental stressors shape community composition and ecosystem functioning. Contaminants such as pharmaceuticals are of increasing concern as an environmental stressor due to their persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations; and examination of whole organism effects are necessary to identify potential community-level consequences in estuarine and marine ecosystems. We conducted a long-term exposure study (107 days) with the anti-depressant pharmaceutical, fluoxetine (the active constituent in Prozac®) to determine whether minimal concentrations affected whole organism metrics in the California mussel, Mytilus californianus. We measured algal clearance rates, mussel growth, and the gonadosomatic index, a measure of reproductive health. We found that fluoxetine negatively affects all measured characteristics, however many effects were mediated by length of exposure. Our results fill an important data gap, highlighting organism-level effects of chronic exposure periods; such data more explicitly identify the overall impacts of pharmaceuticals and other contaminants on marine communities and ecosystems. Title: Long-Term Exposure to Fluoxetine Reduces Growth and Reproductive Potential in the Dominant Rocky Intertidal Mussel, Mytilus californianus Author: Peters, Joseph R., Granek, Elise F. Year: 2016 Environmental stressors shape community composition and ecosystem functioning. Contaminants such as pharmaceuticals are of increasing concern as an environmental stressor due to their persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations; and examination of whole organism effects are necessary to identify potential community-level consequences in estuarine and marine ecosystems. We conducted a long-term exposure study (107 days) with the anti-depressant pharmaceutical, fluoxetine (the active constituent in Prozac®) to determine whether minimal concentrations affected whole organism metrics in the California mussel, Mytilus californianus. We measured algal clearance rates, mussel growth, and the gonadosomatic index, a measure of reproductive health. We found that fluoxetine negatively affects all measured characteristics, however many effects were mediated by length of exposure. Our results fill an important data gap, highlighting organism-level effects of chronic exposure periods; such data more explicitly identify the overall impacts of pharmaceuticals and other contaminants on marine communities and ecosystems. Close

• 74. [Article] Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem

  Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification ...

  Citation × Citation Citation Abstract Copy Title: Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem Author: Reese, Douglas Charles Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification of such marine, biological hotspots would be of great importance to resource managers, conservationists, and research planners, and is consequently a growing area of research. Furthermore, in order to understand how ecosystems function and persist, it is necessary to know how ecological communities are distributed. The overall goal of this study is to provide further understanding regarding the functioning of marine ecosystems in such highly variable environments and to provide information about the distribution and structure of marine communities. Sampling was conducted during June and August of 2000 and 2002 as part of the U.S. GLOBEC mesoscale surveys from Newport, Oregon in the north to Crescent City, California in the south. A geostatistical approach was used to create surfaces used in a GIS to determine the distribution of various community characteristics. Two biological hotspots were identified and determined to persist in space and time, yet differed with respect to biological and physical features and in the amount of area covered. Various community analyses, including nonmetric multidimensional scaling, indicator species analysis, and cluster analysis were used to determine various community properties associated with the hotspots and non-hotspot regions. Results indicate that nekton biological hotspots in the northern California Current persist across differing environmental and biological conditions, although upwelling-based hotspots may be more susceptible to climatic conditions than retention-based hotspots. Analyses of the distribution of the functional groups within the region indicate that the predominant biological activity is spatially nonrandom and occurs within persistent, localized areas. Analyses of species associations suggest a moderate degree of redundancy. The presence of such complementary species within functional groups may confer the stability observed within these systems. The finding that large regional areas are composed of smaller, localized hotspots where a predominant amount of biological activity is occurring, suggests that the evaluation of large marine ecosystems may lead to erroneous or misleading results if they do not consider the more persistent, localized biological hotspots. Title: Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem Author: Reese, Douglas Charles Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification of such marine, biological hotspots would be of great importance to resource managers, conservationists, and research planners, and is consequently a growing area of research. Furthermore, in order to understand how ecosystems function and persist, it is necessary to know how ecological communities are distributed. The overall goal of this study is to provide further understanding regarding the functioning of marine ecosystems in such highly variable environments and to provide information about the distribution and structure of marine communities. Sampling was conducted during June and August of 2000 and 2002 as part of the U.S. GLOBEC mesoscale surveys from Newport, Oregon in the north to Crescent City, California in the south. A geostatistical approach was used to create surfaces used in a GIS to determine the distribution of various community characteristics. Two biological hotspots were identified and determined to persist in space and time, yet differed with respect to biological and physical features and in the amount of area covered. Various community analyses, including nonmetric multidimensional scaling, indicator species analysis, and cluster analysis were used to determine various community properties associated with the hotspots and non-hotspot regions. Results indicate that nekton biological hotspots in the northern California Current persist across differing environmental and biological conditions, although upwelling-based hotspots may be more susceptible to climatic conditions than retention-based hotspots. Analyses of the distribution of the functional groups within the region indicate that the predominant biological activity is spatially nonrandom and occurs within persistent, localized areas. Analyses of species associations suggest a moderate degree of redundancy. The presence of such complementary species within functional groups may confer the stability observed within these systems. The finding that large regional areas are composed of smaller, localized hotspots where a predominant amount of biological activity is occurring, suggests that the evaluation of large marine ecosystems may lead to erroneous or misleading results if they do not consider the more persistent, localized biological hotspots. Close

• 75. [Article] Light and the behavior of pelagic animals during night and crepuscular periods

  Light plays an important role in ecological processes in the ocean both day and night. While relatively inexpensive, off the shelf instruments are available to measure Photosynthetically Active Radiation ...

  Citation × Citation Citation Abstract Copy Title: Light and the behavior of pelagic animals during night and crepuscular periods Author: Wisdom, Daniel W. Light plays an important role in ecological processes in the ocean both day and night. While relatively inexpensive, off the shelf instruments are available to measure Photosynthetically Active Radiation or PAR during the day, efforts to quantify light levels at night have proven more difficult. The goal of this work was to quantify nighttime light levels while simultaneously examining the movement of pelagic animals to explore correlations between light levels and the vertical movement of these animals during crepuscular periods and during the rise and set of the moon. This study explores two hypotheses about the role of light with respect to the vertical migration of animals in water. The first is that at a constant depth, light levels correlate with the scattering volume, or abundance, of animals in the water column. The experiment failed to prove this hypothesis; therefore, it is concluded that light is not a significant predictor of the amount of animal scattering volume at a constant depth. The second hypothesis tested is that pelagic animals follow an isolume up and down the water column as light levels change. Experiments showed a wide variance in animal scattering volume along an isolume instead of being relatively constant as would be expected if animals followed an isolume. Additional analysis showed no relationship between volume backscatter and depth. Therefore it is concluded that animals do not follow an isolume up and down the water column as light levels vary. The development of methods to monitor nocturnal behavior of pelagic animals has implications for marine resource management. This study was performed in the Monterey Bay National Marine Sanctuary and provides previously unavailable data to Sanctuary Managers about important nocturnal marine processes. Sanctuary Managers are mandated to use Ecosystem-Based Management principles in managing the Sanctuary. This is a complex marine ecosystem in which the interaction of small scale components can have large influences in macrosystem dynamics which can feed back to influence smaller scale systems again. To assist them, Sanctuary Managers have developed Resource Preservation and Research plans that require data of many types. Experiments incorporating techniques using acoustical instruments to measure abundance and migration patterns of pelagic animals can help Sanctuary Managers better understand the complex linkages of the marine ecosystem in the Monterey Bay National Marine Sanctuary. Title: Light and the behavior of pelagic animals during night and crepuscular periods Author: Wisdom, Daniel W. Light plays an important role in ecological processes in the ocean both day and night. While relatively inexpensive, off the shelf instruments are available to measure Photosynthetically Active Radiation or PAR during the day, efforts to quantify light levels at night have proven more difficult. The goal of this work was to quantify nighttime light levels while simultaneously examining the movement of pelagic animals to explore correlations between light levels and the vertical movement of these animals during crepuscular periods and during the rise and set of the moon. This study explores two hypotheses about the role of light with respect to the vertical migration of animals in water. The first is that at a constant depth, light levels correlate with the scattering volume, or abundance, of animals in the water column. The experiment failed to prove this hypothesis; therefore, it is concluded that light is not a significant predictor of the amount of animal scattering volume at a constant depth. The second hypothesis tested is that pelagic animals follow an isolume up and down the water column as light levels change. Experiments showed a wide variance in animal scattering volume along an isolume instead of being relatively constant as would be expected if animals followed an isolume. Additional analysis showed no relationship between volume backscatter and depth. Therefore it is concluded that animals do not follow an isolume up and down the water column as light levels vary. The development of methods to monitor nocturnal behavior of pelagic animals has implications for marine resource management. This study was performed in the Monterey Bay National Marine Sanctuary and provides previously unavailable data to Sanctuary Managers about important nocturnal marine processes. Sanctuary Managers are mandated to use Ecosystem-Based Management principles in managing the Sanctuary. This is a complex marine ecosystem in which the interaction of small scale components can have large influences in macrosystem dynamics which can feed back to influence smaller scale systems again. To assist them, Sanctuary Managers have developed Resource Preservation and Research plans that require data of many types. Experiments incorporating techniques using acoustical instruments to measure abundance and migration patterns of pelagic animals can help Sanctuary Managers better understand the complex linkages of the marine ecosystem in the Monterey Bay National Marine Sanctuary. Close

• 76. [Article] Incorporation of diet information derived from Bayesian stable isotope mixing models into mass-balanced marine ecosystem models: A case study from the Marennes-Oleron Estuary, France

  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: Incorporation of diet information derived from Bayesian stable isotope mixing models into mass-balanced marine ecosystem models: A case study from the Marennes-Oleron Estuary, France Author: Phillips, Donald, Pacella, Stephen R., Richard, Pierre, DeWitt, Theodore H., Lebreton, Benoit, Niquil, Nathalie 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.elsevier.com/. Title: Incorporation of diet information derived from Bayesian stable isotope mixing models into mass-balanced marine ecosystem models: A case study from the Marennes-Oleron Estuary, France Author: Phillips, Donald, Pacella, Stephen R., Richard, Pierre, DeWitt, Theodore H., Lebreton, Benoit, Niquil, Nathalie 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.elsevier.com/. Close

• 77. [Article] The Effects of Artificial Structures on Estuarine Infaunal Communities and Offshore Biofouling Communities

  For hundreds of years, coastal and marine ecosystems have experienced increasing threats due to the cumulative effects of increasing population growth and dependence on these ecosystems. Thus, there has ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Artificial Structures on Estuarine Infaunal Communities and Offshore Biofouling Communities Author: Mendoza, Maritza For hundreds of years, coastal and marine ecosystems have experienced increasing threats due to the cumulative effects of increasing population growth and dependence on these ecosystems. Thus, there has been increased enthusiasm to mitigate the negative effects of human actions through the use of cleaner sources of energy, like marine renewable energy (MRE). The U.S. West Coast shows potential for tidal, wave, and offshore wind energy. Concern about MRE deployments has motivated research on the environmental effects of these new man-made hard structures in the ocean. Although this kind of development is relatively new in the U.S, placing man-made hard structure in coastal and marine ecosystems around the world has shown to create new habitat for algae, invertebrates, and fish and create foraging opportunities for birds and mammals, eventually becoming an artificial reef. The overall goal of my research was to use existing artificial structures to investigate a few specific effects of MRE development in Oregon waters. My research had two components: to assess the extent to which soft-sediment habitats are influenced by the presence of artificial structures deployed in Yaquina Bay, OR, and to characterize the biofouling communities present on bottom and surface artificial structures deployed offshore. Previous research indicates artificial structures modify sediment composition by increasing the erosion around a structure and that there is a close link between infaunal communities and sediment composition. Grain size analyses confirmed artificial structures change the physical environment around them, although these differences were not sufficient to cause a visible change in infaunal communities. Sediment characteristics also did not explain the greater infaunal abundances, mainly of Capitellidae polychaetes, closer to the structures than further away. Results indicated there were significant differences in sediment characteristics between locations in Yaquina Bay, most likely because of the greater amount of fine sediment at the sites located further upstream than those located closer to the mouth of the estuary. These differences in sediment characteristics appeared to be large enough to see a grouping of infaunal communities with location in Yaquina Bay. This study provided additional evidence that artificial structures alter their physical environment, but these structures and physical effects did not change the composition of the infaunal communities after a period of eight years. Assessing the biofouling cover on the offshore bottom and surface artificial structures showed that after a period of two years, the biofouling communities on the offshore bottom structures mostly consisted of balanoid barnacles, which resulted in little biomass. The bottom structures appeared to have been tipped over during their time in the water, potentially preventing the biofouling communities from developing more. In contrast, the surface artificial structures had greater overall cover, although cover mostly consisted of algae and gooseneck barnacles. Mussels, amphipods, crabs, and bivalves were found within the algae demonstrating the additional structure provided by the algae supported a greater variety of organisms on the surface structure. This study provided a “snapshot” of possible biofouling communities on offshore artificial structures, but longitudinal studies would enable us to monitor the development of the biofouling communities on these structures to better understand the mechanisms that caused the observed biofouling communities. Conducting these studies in an estuarine environment where in-stream tidal energy could be developed and in an offshore environment where wave energy devices would be deployed supplies greater specific knowledge about the possible effects of MRE devices in Oregon waters and also demonstrates the importance of site-specific research. Title: The Effects of Artificial Structures on Estuarine Infaunal Communities and Offshore Biofouling Communities Author: Mendoza, Maritza For hundreds of years, coastal and marine ecosystems have experienced increasing threats due to the cumulative effects of increasing population growth and dependence on these ecosystems. Thus, there has been increased enthusiasm to mitigate the negative effects of human actions through the use of cleaner sources of energy, like marine renewable energy (MRE). The U.S. West Coast shows potential for tidal, wave, and offshore wind energy. Concern about MRE deployments has motivated research on the environmental effects of these new man-made hard structures in the ocean. Although this kind of development is relatively new in the U.S, placing man-made hard structure in coastal and marine ecosystems around the world has shown to create new habitat for algae, invertebrates, and fish and create foraging opportunities for birds and mammals, eventually becoming an artificial reef. The overall goal of my research was to use existing artificial structures to investigate a few specific effects of MRE development in Oregon waters. My research had two components: to assess the extent to which soft-sediment habitats are influenced by the presence of artificial structures deployed in Yaquina Bay, OR, and to characterize the biofouling communities present on bottom and surface artificial structures deployed offshore. Previous research indicates artificial structures modify sediment composition by increasing the erosion around a structure and that there is a close link between infaunal communities and sediment composition. Grain size analyses confirmed artificial structures change the physical environment around them, although these differences were not sufficient to cause a visible change in infaunal communities. Sediment characteristics also did not explain the greater infaunal abundances, mainly of Capitellidae polychaetes, closer to the structures than further away. Results indicated there were significant differences in sediment characteristics between locations in Yaquina Bay, most likely because of the greater amount of fine sediment at the sites located further upstream than those located closer to the mouth of the estuary. These differences in sediment characteristics appeared to be large enough to see a grouping of infaunal communities with location in Yaquina Bay. This study provided additional evidence that artificial structures alter their physical environment, but these structures and physical effects did not change the composition of the infaunal communities after a period of eight years. Assessing the biofouling cover on the offshore bottom and surface artificial structures showed that after a period of two years, the biofouling communities on the offshore bottom structures mostly consisted of balanoid barnacles, which resulted in little biomass. The bottom structures appeared to have been tipped over during their time in the water, potentially preventing the biofouling communities from developing more. In contrast, the surface artificial structures had greater overall cover, although cover mostly consisted of algae and gooseneck barnacles. Mussels, amphipods, crabs, and bivalves were found within the algae demonstrating the additional structure provided by the algae supported a greater variety of organisms on the surface structure. This study provided a “snapshot” of possible biofouling communities on offshore artificial structures, but longitudinal studies would enable us to monitor the development of the biofouling communities on these structures to better understand the mechanisms that caused the observed biofouling communities. Conducting these studies in an estuarine environment where in-stream tidal energy could be developed and in an offshore environment where wave energy devices would be deployed supplies greater specific knowledge about the possible effects of MRE devices in Oregon waters and also demonstrates the importance of site-specific research. Close

• 78. [Article] The great 2012 Arctic Ocean summer cyclone enhanced biological productivity on the shelves

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. on behalf of the American Geophysical Union. The published article can be ...

  Citation × Citation Citation Abstract Copy Title: The great 2012 Arctic Ocean summer cyclone enhanced biological productivity on the shelves Author: Spitz, Yvette H., Hill, Victoria, Zhang, Jinlun, Campbell, Robert, Steele, Michael, Ashjian, Carin This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. on behalf of the American Geophysical Union. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2169-9291. Title: The great 2012 Arctic Ocean summer cyclone enhanced biological productivity on the shelves Author: Spitz, Yvette H., Hill, Victoria, Zhang, Jinlun, Campbell, Robert, Steele, Michael, Ashjian, Carin This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. on behalf of the American Geophysical Union. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2169-9291. Close

• 79. [Article] Ecology of the northern subpopulation of northern anchovy (Engraulis mordax) in the California Current large marine ecosystem

  Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, ...

  Citation × Citation Citation Abstract Copy Title: Ecology of the northern subpopulation of northern anchovy (Engraulis mordax) in the California Current large marine ecosystem Author: Litz, Marisa N. C. Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, or population fluctuations relative to ocean conditions in the eastern boundary upwelling system off the U.S. West Coast. This thesis includes three primary studies of northern anchovy in the CCLME off Oregon and Washington using data collected during four National Marine Fisheries Service (NMFS) surveys (1977-2006): inter- and intra-annual variation in anchovy distribution and its relationship to oceanography, growth rates of larval and juvenile anchovy that indicate the timing of major spawning events and changes in mortality rates, and analysis of whole lipids and fatty acid profiles to determine food sources in years of contrasting oceanographic conditions. First, I quantified the relationship between northern anchovy abundance with environmental variables at two spatial and temporal scales: 1) mesoscale, including sea surface temperature (SST), salinity (SSS), density (SSD), chlorophyll a, distance from shore, and depth; and 2) macroscale, including Pacific Decadal Oscillation Index, Multivariate El Niño Southern Oscillation Index, timing of the Spring Transition, and abundance of cold-water zooplankton. Anchovy densities increased significantly from 1999-2004, and decreased significantly from 2005-2006. SST and proximity to shore were the most consistent parameters explaining anchovy distribution. Year-class strength was highly correlated with, and presumably driven by, the abundance of cold-water copepods. Second, I characterized recruitment for northern anchovy by conducting microstructure analysis of saggital otoliths from late larval and juvenile life history phases collected in September 2006. I identified a protracted spawning period for northern anchovy ranging from June-August 2006. Juveniles that were spawned and hatched early in the summer 2006 had higher growth rates, but smaller back-calculated sizes-at-age during the larval phase, when compared to congeners spawned later that summer. Finally, I determined total lipid content and fatty acid signatures of northern anchovy and three other forage fish species during two contrasting periods of oceanographic conditions (summers of 2005 and 2006): Pacific sardine (Sardinops sagax), Pacific herring (Clupea harengus pallasii), and whitebait smelt (Allosmerus elongatus). Forage fish lipid levels were lowest in 2005 and increased in 2006. Fatty acid biomarkers in 2005 indicated that the food web was based mainly on dinoflagellates, corroborating observations of delayed coastal upwelling and low primary productivity in the CCLME. In 2006, fatty acids reflected higher levels of diatom feeding and zooplankton carnivory. The results of these studies confirm that in the CCLME, northern anchovy are sensitive to even small environmental perturbations, which is important because this work provides metrics for evaluating climate-mediated, bottom-up ecological processes affecting anchovy survival. Title: Ecology of the northern subpopulation of northern anchovy (Engraulis mordax) in the California Current large marine ecosystem Author: Litz, Marisa N. C. Northern anchovy (Engraulis mordax) are a dominant forage fish in the California Current large marine ecosystem (CCLME). However, little is known about northern anchovy abundance, distribution, age structure, or population fluctuations relative to ocean conditions in the eastern boundary upwelling system off the U.S. West Coast. This thesis includes three primary studies of northern anchovy in the CCLME off Oregon and Washington using data collected during four National Marine Fisheries Service (NMFS) surveys (1977-2006): inter- and intra-annual variation in anchovy distribution and its relationship to oceanography, growth rates of larval and juvenile anchovy that indicate the timing of major spawning events and changes in mortality rates, and analysis of whole lipids and fatty acid profiles to determine food sources in years of contrasting oceanographic conditions. First, I quantified the relationship between northern anchovy abundance with environmental variables at two spatial and temporal scales: 1) mesoscale, including sea surface temperature (SST), salinity (SSS), density (SSD), chlorophyll a, distance from shore, and depth; and 2) macroscale, including Pacific Decadal Oscillation Index, Multivariate El Niño Southern Oscillation Index, timing of the Spring Transition, and abundance of cold-water zooplankton. Anchovy densities increased significantly from 1999-2004, and decreased significantly from 2005-2006. SST and proximity to shore were the most consistent parameters explaining anchovy distribution. Year-class strength was highly correlated with, and presumably driven by, the abundance of cold-water copepods. Second, I characterized recruitment for northern anchovy by conducting microstructure analysis of saggital otoliths from late larval and juvenile life history phases collected in September 2006. I identified a protracted spawning period for northern anchovy ranging from June-August 2006. Juveniles that were spawned and hatched early in the summer 2006 had higher growth rates, but smaller back-calculated sizes-at-age during the larval phase, when compared to congeners spawned later that summer. Finally, I determined total lipid content and fatty acid signatures of northern anchovy and three other forage fish species during two contrasting periods of oceanographic conditions (summers of 2005 and 2006): Pacific sardine (Sardinops sagax), Pacific herring (Clupea harengus pallasii), and whitebait smelt (Allosmerus elongatus). Forage fish lipid levels were lowest in 2005 and increased in 2006. Fatty acid biomarkers in 2005 indicated that the food web was based mainly on dinoflagellates, corroborating observations of delayed coastal upwelling and low primary productivity in the CCLME. In 2006, fatty acids reflected higher levels of diatom feeding and zooplankton carnivory. The results of these studies confirm that in the CCLME, northern anchovy are sensitive to even small environmental perturbations, which is important because this work provides metrics for evaluating climate-mediated, bottom-up ecological processes affecting anchovy survival. Close

• 80. [Article] Behavioral ecology of marbled murrelets (Brachyramphus marmoratus) in forest and marine ecosystems of Oregon

  Marbled Murrelets (Brachyramphus marmoratus) are threatened seabirds that are prone to disturbance both at sea and at old-growth forest nesting areas. I examined murrelet behavior and activity patterns ...

  Citation × Citation Citation Abstract Copy Title: Behavioral ecology of marbled murrelets (Brachyramphus marmoratus) in forest and marine ecosystems of Oregon Author: Jodice, Patrick G. R., 1961- Marbled Murrelets (Brachyramphus marmoratus) are threatened seabirds that are prone to disturbance both at sea and at old-growth forest nesting areas. I examined murrelet behavior and activity patterns in forest and marine ecosystems of Oregon. Diving behavior was studied during the 1995 and 1996 breeding seasons and was compared to predictions from optimal breathing models, which predicted a strong relationship between dive times and preceding pause times. Diving patterns appeared to fit these predictions more in 1996 than 1995 suggesting that diving behavior was affected more by annual changes in environmental conditions than by physiological constraints on breathing and diving as predicted by optimal breathing models. Activity patterns at inland nest sites were monitored on a near-daily basis during three breeding seasons to assess the relationships between activity and both weather and date. Daily activity was highly variable within and among sites and years and I observed greater variability in activity levels than has been previously reported for this species. Activity varied greatly during all portions of the breeding season and analyses revealed that weather and date variates explained little of the variability present. It also appeared that variability in activity during the breeding season was not due entirely to breeding phenology; however, activity of nonbreeding birds attending nesting stands may contribute to daily variability. Inland activity data also were used to assess the feasibility of developing long-term monitoring strategies based on counts of daily detections. I determined how effectively various survey strategies estimated measures of daily mean and standard deviation of detection counts of murrelets within a breeding season. Results indicated that it would be difficult to obtain reliable estimates of murrelet detections with sampling efforts up to 14 days/season. However, estimates of mean and standard deviation for daily detections during a breeding season may be reliably estimated to within ± 50% with similar or less effort. The power of survey strategies to detect annual declines in detections of 25% and 50% were very low and moderate, respectively, except when variability was quite low. Title: Behavioral ecology of marbled murrelets (Brachyramphus marmoratus) in forest and marine ecosystems of Oregon Author: Jodice, Patrick G. R., 1961- Marbled Murrelets (Brachyramphus marmoratus) are threatened seabirds that are prone to disturbance both at sea and at old-growth forest nesting areas. I examined murrelet behavior and activity patterns in forest and marine ecosystems of Oregon. Diving behavior was studied during the 1995 and 1996 breeding seasons and was compared to predictions from optimal breathing models, which predicted a strong relationship between dive times and preceding pause times. Diving patterns appeared to fit these predictions more in 1996 than 1995 suggesting that diving behavior was affected more by annual changes in environmental conditions than by physiological constraints on breathing and diving as predicted by optimal breathing models. Activity patterns at inland nest sites were monitored on a near-daily basis during three breeding seasons to assess the relationships between activity and both weather and date. Daily activity was highly variable within and among sites and years and I observed greater variability in activity levels than has been previously reported for this species. Activity varied greatly during all portions of the breeding season and analyses revealed that weather and date variates explained little of the variability present. It also appeared that variability in activity during the breeding season was not due entirely to breeding phenology; however, activity of nonbreeding birds attending nesting stands may contribute to daily variability. Inland activity data also were used to assess the feasibility of developing long-term monitoring strategies based on counts of daily detections. I determined how effectively various survey strategies estimated measures of daily mean and standard deviation of detection counts of murrelets within a breeding season. Results indicated that it would be difficult to obtain reliable estimates of murrelet detections with sampling efforts up to 14 days/season. However, estimates of mean and standard deviation for daily detections during a breeding season may be reliably estimated to within ± 50% with similar or less effort. The power of survey strategies to detect annual declines in detections of 25% and 50% were very low and moderate, respectively, except when variability was quite low. Close