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• 1. [Article] Currents in Fishery Management

  This thesis provides an overview of fishery management policy types and attempts to determine best practices for biological sustainability in terms of species preservation and biomass recovery. Key concepts ...

  Citation × Citation Citation Abstract Copy Title: Currents in Fishery Management Author: DePuy, Genevieve Year: 2016 This thesis provides an overview of fishery management policy types and attempts to determine best practices for biological sustainability in terms of species preservation and biomass recovery. Key concepts include biological sustainability, regulatory forces, and fishery management and output trends. The research question investigated is: what are the best policy practices for regulating marine fishery health and biological stability? The research process of this paper included a review of prior literature in the field of marine policy and fishery management, as well as the use of United States data from the Pacific and Atlantic coasts to evaluate management strategies. Based on both the literature review and the results of the data from Pacific and Atlantic Fisheries, the best management structure appears to be the co-management approach while the best management methodologies involve ecosystem protections and quotas. Title: Currents in Fishery Management Author: DePuy, Genevieve Year: 2016 This thesis provides an overview of fishery management policy types and attempts to determine best practices for biological sustainability in terms of species preservation and biomass recovery. Key concepts include biological sustainability, regulatory forces, and fishery management and output trends. The research question investigated is: what are the best policy practices for regulating marine fishery health and biological stability? The research process of this paper included a review of prior literature in the field of marine policy and fishery management, as well as the use of United States data from the Pacific and Atlantic coasts to evaluate management strategies. Based on both the literature review and the results of the data from Pacific and Atlantic Fisheries, the best management structure appears to be the co-management approach while the best management methodologies involve ecosystem protections and quotas. Close

• 2. [Article] Bio-Economic Analysis for Arctic Marine Resource Management Policy

  Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, ...

  Citation × Citation Citation Abstract Copy Title: Bio-Economic Analysis for Arctic Marine Resource Management Policy Author: Vestergaard, Niels Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Title: Bio-Economic Analysis for Arctic Marine Resource Management Policy Author: Vestergaard, Niels Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Close

• 3. [Article] Neoliberal and Neo-Communal Herring Fisheries in Southeast Alaska: Reframing Sustainability in Marine Ecosystems

  The transformation of Pacific herring (Clupea pallasii) fisheries from communal to commons to neoliberal regulation has had significant impacts on the health and sustainability of marine ecosystems on ...

  Citation × Citation Citation Abstract Copy Title: Neoliberal and Neo-Communal Herring Fisheries in Southeast Alaska: Reframing Sustainability in Marine Ecosystems Author: Thornton, Thomas F., Hebert, Jamie Year: 2015 The transformation of Pacific herring (Clupea pallasii) fisheries from communal to commons to neoliberal regulation has had significant impacts on the health and sustainability of marine ecosystems on the Northwest Coast of North America. Due to their abundance, seasonality, and sensitivity in disturbance, herring were carefully cultivated and protected by coastal Tlingit, Haida, and Tsimshian communities. The early industrial fishing era undermined this communalist approach in favor of an unregulated commons for bait and reduction fisheries, attracting non-local fleets and leading to conflicts with local Natives and tragedy of the commons style overexploitation of herring stocks by the mid-twentieth century. Since the 1970s, a re-regulated neoliberal sac roe fishery for Japanese markets has provided new opportunities for limited commercial permit holders, but with further depredations on local spawning populations. This paper uses frame theory and historical and political ecology to show how this transformation was justified by three critical but dubious (re)framings of Southeast herring populations under modern scientific management: (1) a reductionist framing of single species productivity models, expressed as herring “biomass,” within space and time (baseline scale framing); (2) the selective framing and privileging of human industrial predation under maximum sustainable yield (MSY) within a dynamic ecosystem of multiple predator populations (actor relations framing); and (3) the strategic framing of spawning failure events and policy responses to those events by professional fisheries managers (event–response framing). Finally, the paper argues for a new social–ecological systems approach, based on aboriginal models of herring cultivation, to sustain a commercial, subsistence, and restoration economy for the fishery. Title: Neoliberal and Neo-Communal Herring Fisheries in Southeast Alaska: Reframing Sustainability in Marine Ecosystems Author: Thornton, Thomas F., Hebert, Jamie Year: 2015 The transformation of Pacific herring (Clupea pallasii) fisheries from communal to commons to neoliberal regulation has had significant impacts on the health and sustainability of marine ecosystems on the Northwest Coast of North America. Due to their abundance, seasonality, and sensitivity in disturbance, herring were carefully cultivated and protected by coastal Tlingit, Haida, and Tsimshian communities. The early industrial fishing era undermined this communalist approach in favor of an unregulated commons for bait and reduction fisheries, attracting non-local fleets and leading to conflicts with local Natives and tragedy of the commons style overexploitation of herring stocks by the mid-twentieth century. Since the 1970s, a re-regulated neoliberal sac roe fishery for Japanese markets has provided new opportunities for limited commercial permit holders, but with further depredations on local spawning populations. This paper uses frame theory and historical and political ecology to show how this transformation was justified by three critical but dubious (re)framings of Southeast herring populations under modern scientific management: (1) a reductionist framing of single species productivity models, expressed as herring “biomass,” within space and time (baseline scale framing); (2) the selective framing and privileging of human industrial predation under maximum sustainable yield (MSY) within a dynamic ecosystem of multiple predator populations (actor relations framing); and (3) the strategic framing of spawning failure events and policy responses to those events by professional fisheries managers (event–response framing). Finally, the paper argues for a new social–ecological systems approach, based on aboriginal models of herring cultivation, to sustain a commercial, subsistence, and restoration economy for the fishery. Close

• 4. [Article] Information Needs Assessment for Coastal and Marine Management and Policy: Ecosystem Services Under Changing Climatic, Land Use, and Demographic Conditions

  Changing climatic, demographic, and land use conditions are projected to alter the provisioning of ecosystem services in estuarine, coastal, and nearshore marine ecosystems, necessitating mitigation and ...

  Citation × Citation Citation Abstract Copy Title: Information Needs Assessment for Coastal and Marine Management and Policy: Ecosystem Services Under Changing Climatic, Land Use, and Demographic Conditions Author: Goldsmith, Kaitlin, Granek, Elise F., Lubitow, Amy Year: 2015 Changing climatic, demographic, and land use conditions are projected to alter the provisioning of ecosystem services in estuarine, coastal, and nearshore marine ecosystems, necessitating mitigation and adaptation policies and management. The current paradigm of research efforts occurring in parallel to, rather than in collaboration with, decision makers will be insufficient for the rapid responses required to adapt to and mitigate for projected changing conditions. Here, we suggest a different paradigm: one where research begins by engaging decision makers in the identification of priority data needs (biophysical, economic, and social). This paper uses synthesized interview data to provide insight into the varied demands for scientific research as described by decision makers working on coastal issues in Oregon, USA. The findings highlight the need to recognize (1) the differing framing of ecosystem services by decision makers versus scientists; and (2) the differing data priorities relevant to inland versus coastal decision makers. The findings further serve to highlight the need for decision makers, scientists, and funders to engage in increased communication. This research is an important first step in advancing efforts toward evidence-based decision making in Oregon and provides a template for further research across the US. Title: Information Needs Assessment for Coastal and Marine Management and Policy: Ecosystem Services Under Changing Climatic, Land Use, and Demographic Conditions Author: Goldsmith, Kaitlin, Granek, Elise F., Lubitow, Amy Year: 2015 Changing climatic, demographic, and land use conditions are projected to alter the provisioning of ecosystem services in estuarine, coastal, and nearshore marine ecosystems, necessitating mitigation and adaptation policies and management. The current paradigm of research efforts occurring in parallel to, rather than in collaboration with, decision makers will be insufficient for the rapid responses required to adapt to and mitigate for projected changing conditions. Here, we suggest a different paradigm: one where research begins by engaging decision makers in the identification of priority data needs (biophysical, economic, and social). This paper uses synthesized interview data to provide insight into the varied demands for scientific research as described by decision makers working on coastal issues in Oregon, USA. The findings highlight the need to recognize (1) the differing framing of ecosystem services by decision makers versus scientists; and (2) the differing data priorities relevant to inland versus coastal decision makers. The findings further serve to highlight the need for decision makers, scientists, and funders to engage in increased communication. This research is an important first step in advancing efforts toward evidence-based decision making in Oregon and provides a template for further research across the US. Close

• 5. [Article] Ultrasonic Bone Assessment in Tursiops Truncatus: A Proposed Means for Monitoring Marine Ecosystem Health

  In order to circumvent limitations in traditional radiographic bone density assessment, a custom quantitative ultrasound device and protocols were developed for assessment of live bottlenose dolphins, ...

  Citation × Citation Citation Abstract Copy Title: Ultrasonic Bone Assessment in Tursiops Truncatus: A Proposed Means for Monitoring Marine Ecosystem Health Author: Powell, James, Luo, Gangming, Kaufman, Jonathan J. Year: 2015 In order to circumvent limitations in traditional radiographic bone density assessment, a custom quantitative ultrasound device and protocols were developed for assessment of live bottlenose dolphins, Tursiops truncatus. In laboratory measurements on disarticulated pectoral flippers collected post-mortem, a strong correlation was established between bone mineral density (BMD) as measured with quantitative ultrasound and X-ray (r=0.93). A primary target skeletal site in the radius of the dolphin pectoral fin was comprehensively defined. BMD distribution patterns throughout the radius were characterized and a single region of interest (ROI) with a high correlation to the density of the overall bone (r=0.98) was selected. Statistical tests demonstrated no statistically significant differences in any subset based on sex, age, total body length, handedness, nutritional status, or geographical affinity, supporting inclusion of all specimens as a normative reference dataset for bone density in bottlenose dolphins. Initial trials to develop clinical protocols and establish ultrasound of bone as truly non-invasive were conducted on captive dolphins. Successful assessments were subsequently conducted to ultrasonically assess BMD in wild dolphins during capture-release health assessments. Title: Ultrasonic Bone Assessment in Tursiops Truncatus: A Proposed Means for Monitoring Marine Ecosystem Health Author: Powell, James, Luo, Gangming, Kaufman, Jonathan J. Year: 2015 In order to circumvent limitations in traditional radiographic bone density assessment, a custom quantitative ultrasound device and protocols were developed for assessment of live bottlenose dolphins, Tursiops truncatus. In laboratory measurements on disarticulated pectoral flippers collected post-mortem, a strong correlation was established between bone mineral density (BMD) as measured with quantitative ultrasound and X-ray (r=0.93). A primary target skeletal site in the radius of the dolphin pectoral fin was comprehensively defined. BMD distribution patterns throughout the radius were characterized and a single region of interest (ROI) with a high correlation to the density of the overall bone (r=0.98) was selected. Statistical tests demonstrated no statistically significant differences in any subset based on sex, age, total body length, handedness, nutritional status, or geographical affinity, supporting inclusion of all specimens as a normative reference dataset for bone density in bottlenose dolphins. Initial trials to develop clinical protocols and establish ultrasound of bone as truly non-invasive were conducted on captive dolphins. Successful assessments were subsequently conducted to ultrasonically assess BMD in wild dolphins during capture-release health assessments. Close

• 6. [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

• 7. [Article] Effects of Environmentally-Relevant Antibiotic Mixtures on Marine Microalgal Growth

  As of 2008, approximately 48% of Americans use prescription drugs within any given 30-day period. Many pharmaceutical compounds are not fully metabolized by the human body, nor fully removed by wastewater ...

  Citation × Citation Citation Abstract Copy Title: Effects of Environmentally-Relevant Antibiotic Mixtures on Marine Microalgal Growth Author: Teixeira, Jaclyn R., Granek, Elise F. Year: 2017 As of 2008, approximately 48% of Americans use prescription drugs within any given 30-day period. Many pharmaceutical compounds are not fully metabolized by the human body, nor fully removed by wastewater treatment systems, before release into the environment. As a result, a vast array of pharmaceuticals has been detected in marine and freshwater organisms, sediments, and waters, with unintended effects on non-target organisms, and limited studies of environmental effects. The antibiotics sulfamethoxazole (SMX), and trimethoprim (TRI), often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 765–870 ng/L each. Little research has examined sub-lethal effects of antibiotic mixtures at environmentally-relevant concentrations on marine organisms. We examined the effects of mixtures of these two antibiotics on three marine microalgal species with wide geographic ranges: Isochrysis galbana, Chaetoceros neogracile, and Nannochloropsis oculata. In separate simulations using a temperature/light-controlled set-up, we measured the growth response for each species to environmentally-relevant levels of SMX and TRI. N. oculata growth was significantly reduced by mixture treatments of both drugs (p < 0.05), by TRI (p < 0.001), and by SMX (p < 0.001), whereas only aggregated SMX levels significantly reduced growth for the other two species (p < 0.005). The exposure time at which growth rates were affected varied across species, with significant reduction in growth focused in the latter half of the experimental period for C. neogracile and N. oculata (Days 15 and 6 respectively), and midway through the experimental period for I. galbana (by Day 3). This study finds that important marine primary producers respond to the presence of SMX and TRI in the water, offering an understanding of environmental consequences of anthropogenic pharmaceuticals contaminants, and specifically the suite of antibiotics, that are released into marine ecosystems at an ever-growing rate, and highlighting potential cascading effects through trophic levels. Title: Effects of Environmentally-Relevant Antibiotic Mixtures on Marine Microalgal Growth Author: Teixeira, Jaclyn R., Granek, Elise F. Year: 2017 As of 2008, approximately 48% of Americans use prescription drugs within any given 30-day period. Many pharmaceutical compounds are not fully metabolized by the human body, nor fully removed by wastewater treatment systems, before release into the environment. As a result, a vast array of pharmaceuticals has been detected in marine and freshwater organisms, sediments, and waters, with unintended effects on non-target organisms, and limited studies of environmental effects. The antibiotics sulfamethoxazole (SMX), and trimethoprim (TRI), often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 765–870 ng/L each. Little research has examined sub-lethal effects of antibiotic mixtures at environmentally-relevant concentrations on marine organisms. We examined the effects of mixtures of these two antibiotics on three marine microalgal species with wide geographic ranges: Isochrysis galbana, Chaetoceros neogracile, and Nannochloropsis oculata. In separate simulations using a temperature/light-controlled set-up, we measured the growth response for each species to environmentally-relevant levels of SMX and TRI. N. oculata growth was significantly reduced by mixture treatments of both drugs (p < 0.05), by TRI (p < 0.001), and by SMX (p < 0.001), whereas only aggregated SMX levels significantly reduced growth for the other two species (p < 0.005). The exposure time at which growth rates were affected varied across species, with significant reduction in growth focused in the latter half of the experimental period for C. neogracile and N. oculata (Days 15 and 6 respectively), and midway through the experimental period for I. galbana (by Day 3). This study finds that important marine primary producers respond to the presence of SMX and TRI in the water, offering an understanding of environmental consequences of anthropogenic pharmaceuticals contaminants, and specifically the suite of antibiotics, that are released into marine ecosystems at an ever-growing rate, and highlighting potential cascading effects through trophic levels. Close

• 8. [Article] The Economic Implications of Changing Regulations for Deep Sea Fishing under the European Common Fisheries Policy: UK Case Study

  Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, ...

  Citation × Citation Citation Abstract Copy Title: The Economic Implications of Changing Regulations for Deep Sea Fishing under the European Common Fisheries Policy: UK Case Study Author: Mangi, Stephen, Burns, Finlay, Neat, Francis, Kenny, Andrew, Ribeiro-Santos, Ana, Posen, Paulette, Readdy, Lisa Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Title: The Economic Implications of Changing Regulations for Deep Sea Fishing under the European Common Fisheries Policy: UK Case Study Author: Mangi, Stephen, Burns, Finlay, Neat, Francis, Kenny, Andrew, Ribeiro-Santos, Ana, Posen, Paulette, Readdy, Lisa Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Close

• 9. [Article] Investigating Variation in Coral Reef Morphology with Photomosaics and Analysis of Percent Cover

  42 pages

  Citation × Citation Citation Abstract Copy Title: Investigating Variation in Coral Reef Morphology with Photomosaics and Analysis of Percent Cover Author: Culman, Justin Year: 2017 42 pages Title: Investigating Variation in Coral Reef Morphology with Photomosaics and Analysis of Percent Cover Author: Culman, Justin Year: 2017 42 pages Close

• 10. [Article] Effects of Antibiotic Mixtures across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations

  Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, ...

  Citation × Citation Citation Abstract Copy Title: Effects of Antibiotic Mixtures across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations Author: Teixeira, Jaclyn Rebecca Year: 2016 Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, only fairly recent efforts have examined the potential impacts of these drugs on non-target organisms. The antibiotics sulfamethoxazole and trimethoprim, often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 700-800 ng/L each. Toxic effects of these drugs have been identified in freshwater organisms, with synergistic effects observed in short-term studies of mixtures of the two; however, little research has examined possible sub-lethal and longer-term effects of antibiotics in environmentally-relevant mixture concentrations on marine organisms. I examined the long-term effects of mixtures of these two antibiotics in species of a marine system: marine microalgal species, and marine mussels, to determine whether the levels currently present in waterways affect organism health and reproduction. Microalgal species may be among the most sensitive organisms to pharmaceutical contaminants based on ecotoxicity research. I exposed three species of marine microalgae (Isochrysis galbana, Chaetoceros neogracile, and Nannochloropsis oculata) to environmentally-relevant mixtures of sulfamethoxazole and trimethoprim and examined their three-week growth rates. I found that for each species, the antibiotic treatments significantly suppressed algal growth. Specifically, I found that sulfamethoxazole was a driving factor in suppression of C. neogracile and I. galbana growth, while N. oculata responded more sensitively to a broader range of treatment mixture levels, which also included trimethoprim-only treatment groups and mixtures. These results on marine microalgae address critical data gaps, and identify the impacts of pharmaceuticals on marine primary producers, which could have direct ecosystem implications to higher trophic levels. Antibiotic pharmaceuticals can also affect marine mussel health, based on previous study of sub-cellular endpoints. I hypothesized that the important benthic foundational species, the Mytilus californianus mussel, would be significantly impacted by long-term 12-week exposure to environmentally-relevant concentrations and mixtures of sulfamethoxazole and trimethoprim. Specifically, I measured growth rate, feeding rate, condition index, and gonando-somatic index as indicators of whole-organism and reproductive health. Sulfamethoxazole concentrations, in particular, and trimethoprim to a lesser extent, suppressed mussel growth and significantly affected condition index and gonandosomatic index over time. The results of this study offer an understanding of how an intertidal system responds to chronic presence of antibiotic mixtures in the water, and a more complete picture of the environmental consequences of pharmaceutical contaminants released into marine ecosystems at ever-growing rates. Title: Effects of Antibiotic Mixtures across Marine Intertidal Trophic Levels: Examining Environmentally-Relevant Contaminant Concentrations Author: Teixeira, Jaclyn Rebecca Year: 2016 Approximately 48% of Americans use prescription drugs within each 30-day period, and there are signs this trend is increasing. Although many studies track pharmaceuticals’ fates in contaminating waterways, only fairly recent efforts have examined the potential impacts of these drugs on non-target organisms. The antibiotics sulfamethoxazole and trimethoprim, often prescribed together to treat bacterial infections, have been detected worldwide in marine and estuarine environments at concentrations up to 700-800 ng/L each. Toxic effects of these drugs have been identified in freshwater organisms, with synergistic effects observed in short-term studies of mixtures of the two; however, little research has examined possible sub-lethal and longer-term effects of antibiotics in environmentally-relevant mixture concentrations on marine organisms. I examined the long-term effects of mixtures of these two antibiotics in species of a marine system: marine microalgal species, and marine mussels, to determine whether the levels currently present in waterways affect organism health and reproduction. Microalgal species may be among the most sensitive organisms to pharmaceutical contaminants based on ecotoxicity research. I exposed three species of marine microalgae (Isochrysis galbana, Chaetoceros neogracile, and Nannochloropsis oculata) to environmentally-relevant mixtures of sulfamethoxazole and trimethoprim and examined their three-week growth rates. I found that for each species, the antibiotic treatments significantly suppressed algal growth. Specifically, I found that sulfamethoxazole was a driving factor in suppression of C. neogracile and I. galbana growth, while N. oculata responded more sensitively to a broader range of treatment mixture levels, which also included trimethoprim-only treatment groups and mixtures. These results on marine microalgae address critical data gaps, and identify the impacts of pharmaceuticals on marine primary producers, which could have direct ecosystem implications to higher trophic levels. Antibiotic pharmaceuticals can also affect marine mussel health, based on previous study of sub-cellular endpoints. I hypothesized that the important benthic foundational species, the Mytilus californianus mussel, would be significantly impacted by long-term 12-week exposure to environmentally-relevant concentrations and mixtures of sulfamethoxazole and trimethoprim. Specifically, I measured growth rate, feeding rate, condition index, and gonando-somatic index as indicators of whole-organism and reproductive health. Sulfamethoxazole concentrations, in particular, and trimethoprim to a lesser extent, suppressed mussel growth and significantly affected condition index and gonandosomatic index over time. The results of this study offer an understanding of how an intertidal system responds to chronic presence of antibiotic mixtures in the water, and a more complete picture of the environmental consequences of pharmaceutical contaminants released into marine ecosystems at ever-growing rates. Close