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• 81. [Article] The Factors Affecting the Diets of Groundfish in the Gulf of Alaska : Ecological and Modeling Considerations

  Marine systems undergo changes in community composition over time as a result of a variety of environmental and anthropogenic factors. Understanding these community changes and the factors that drive them ...

  Citation × Citation Citation Abstract Copy Title: The Factors Affecting the Diets of Groundfish in the Gulf of Alaska : Ecological and Modeling Considerations Author: Thompson, Kevin A. Marine systems undergo changes in community composition over time as a result of a variety of environmental and anthropogenic factors. Understanding these community changes and the factors that drive them is critical for ecosystem management of marine resources. The Gulf of Alaska (GOA) is a large marine ecosystem that includes a variety of species that support large scale fisheries. This is also a system in which large scale community shifts, or regime shifts, have occurred due to the Pacific Decadal Oscillation (PDO) and fishing pressure. Given the economic and conservation importance of this marine system, the GOA has been modeled using a variety of multispecies, or ecosystem, models. While this work has been critical in understanding the ecosystem dynamics of the GOA and helped generate management recommendations for commercial species, these models often make assumptions regarding trophic-dynamics, particularly that predator-prey relationships follow a standard functional response and do not change through time in response to environmental variables. However, empirical evidence suggests that a predator's diet can be influenced by a variety of factors, abiotic and biotic, at large and small spatial scales. Our overall objective was to investigate the potential impact environmental variables may have in structuring this ecosystem by using statistical analyses of diets and an ecosystem modeling framework. We focused on three commercially and ecologically important groundfish predators: Pacific Cod (Gadus macrocephalus), Pacific Halibut (Hippoglossus stenolepis), and Sablefish (Anoplopoma fimbria). We also focused on a key prey species, Walleye Pollock (Gadus chalcogrammus), and used environmental data collected during trawl surveys and PDO data generated for the entire North Pacific region. The first study completed was focused solely on the consumption of Walleye Pollock, a critical fishery species and ecosystem link. We used data from trawl surveys to determine the potential influence of local environmental variables on the predation rate of Walleye Pollock in the system by these groundfish. Using an information-theoretic approach, we found that predator length was positively related to Walleye Pollock presence and proportion of total diet weight in all predators. Increased temperatures positively affected consumption of Walleye Pollock by Pacific Halibut, but not the other predators. We found evidence for a number of inter-predator effects of co-occurring predators, both positive (facultative) and negative (competitive). Observed prey density was not statistically significant with respect to consumption for these predators, suggesting that trawls sample the environment differently than Walleye Pollock predators or species interactions are more complex than those used in previous multispecies models. In our second study, we considered the entire diet of these predators, rather than one key prey. Furthermore, because PDO had been described as leading to community changes in the system previously, we hypothesized that it could also be driving shifts in diets in the three groundfish predators we studied. We used a multivariate statistical approach to compare the diets of these predators by PDO state (warm or cold years) and also included local environmental covariates. Overall, we found that diets observed in PDO cold years were significantly different than diets in fish in warm years. In general, predators were found to be consuming more Walleye Pollock and euphausiids in warm years, and more benthic invertebrates and other forage fish in cold years. Local environmental covariates contributed to the diets observed in these predators, however no general pattern was observed. Our results also show the benefit of using diet data from large scale monitoring efforts as indicators of community shifts in a large marine ecosystem through time. Ultimately, we used our statistical analyses regarding diet and PDO state to drive a modeling exercise using alternate representations of the diets of the predators in the GOA. We investigated the potential impact of shifting diets in groundfish in an ecosystem-modeling framework, using Ecopath trophic-mass balance models. We changed the diets of key groundfish predators in the model based on our previous results for three alternative model parametrizations; 1) average conditions over the time period, 2) cold PDO state, and 3) warm PDO state. We noted a number of differences in model estimated ecosystem indices. Biomass accumulation estimates indicated that some ecologically and commercially important species groups would be expected to greatly diverge in population size if models were based on data from warm vs. cold PDO years compared to the averaged climatic state. In general, predator overlap was at its lowest in the cold year model, as predators had more diverse diets and therefore predation was more diffuse in the system in general. These results indicate the potential importance of environmental context when collecting diet data to be used in ecosystem models designed to provide fishery management recommendations. As ecosystem models are used more commonly, taking the time to investigate the factors that structure diets and how predation changes due to environment can yield more representative, and potentially more accurate biomass projections and recommendations for the GOA and likely many other managed marine ecosystems. Title: The Factors Affecting the Diets of Groundfish in the Gulf of Alaska : Ecological and Modeling Considerations Author: Thompson, Kevin A. Marine systems undergo changes in community composition over time as a result of a variety of environmental and anthropogenic factors. Understanding these community changes and the factors that drive them is critical for ecosystem management of marine resources. The Gulf of Alaska (GOA) is a large marine ecosystem that includes a variety of species that support large scale fisheries. This is also a system in which large scale community shifts, or regime shifts, have occurred due to the Pacific Decadal Oscillation (PDO) and fishing pressure. Given the economic and conservation importance of this marine system, the GOA has been modeled using a variety of multispecies, or ecosystem, models. While this work has been critical in understanding the ecosystem dynamics of the GOA and helped generate management recommendations for commercial species, these models often make assumptions regarding trophic-dynamics, particularly that predator-prey relationships follow a standard functional response and do not change through time in response to environmental variables. However, empirical evidence suggests that a predator's diet can be influenced by a variety of factors, abiotic and biotic, at large and small spatial scales. Our overall objective was to investigate the potential impact environmental variables may have in structuring this ecosystem by using statistical analyses of diets and an ecosystem modeling framework. We focused on three commercially and ecologically important groundfish predators: Pacific Cod (Gadus macrocephalus), Pacific Halibut (Hippoglossus stenolepis), and Sablefish (Anoplopoma fimbria). We also focused on a key prey species, Walleye Pollock (Gadus chalcogrammus), and used environmental data collected during trawl surveys and PDO data generated for the entire North Pacific region. The first study completed was focused solely on the consumption of Walleye Pollock, a critical fishery species and ecosystem link. We used data from trawl surveys to determine the potential influence of local environmental variables on the predation rate of Walleye Pollock in the system by these groundfish. Using an information-theoretic approach, we found that predator length was positively related to Walleye Pollock presence and proportion of total diet weight in all predators. Increased temperatures positively affected consumption of Walleye Pollock by Pacific Halibut, but not the other predators. We found evidence for a number of inter-predator effects of co-occurring predators, both positive (facultative) and negative (competitive). Observed prey density was not statistically significant with respect to consumption for these predators, suggesting that trawls sample the environment differently than Walleye Pollock predators or species interactions are more complex than those used in previous multispecies models. In our second study, we considered the entire diet of these predators, rather than one key prey. Furthermore, because PDO had been described as leading to community changes in the system previously, we hypothesized that it could also be driving shifts in diets in the three groundfish predators we studied. We used a multivariate statistical approach to compare the diets of these predators by PDO state (warm or cold years) and also included local environmental covariates. Overall, we found that diets observed in PDO cold years were significantly different than diets in fish in warm years. In general, predators were found to be consuming more Walleye Pollock and euphausiids in warm years, and more benthic invertebrates and other forage fish in cold years. Local environmental covariates contributed to the diets observed in these predators, however no general pattern was observed. Our results also show the benefit of using diet data from large scale monitoring efforts as indicators of community shifts in a large marine ecosystem through time. Ultimately, we used our statistical analyses regarding diet and PDO state to drive a modeling exercise using alternate representations of the diets of the predators in the GOA. We investigated the potential impact of shifting diets in groundfish in an ecosystem-modeling framework, using Ecopath trophic-mass balance models. We changed the diets of key groundfish predators in the model based on our previous results for three alternative model parametrizations; 1) average conditions over the time period, 2) cold PDO state, and 3) warm PDO state. We noted a number of differences in model estimated ecosystem indices. Biomass accumulation estimates indicated that some ecologically and commercially important species groups would be expected to greatly diverge in population size if models were based on data from warm vs. cold PDO years compared to the averaged climatic state. In general, predator overlap was at its lowest in the cold year model, as predators had more diverse diets and therefore predation was more diffuse in the system in general. These results indicate the potential importance of environmental context when collecting diet data to be used in ecosystem models designed to provide fishery management recommendations. As ecosystem models are used more commonly, taking the time to investigate the factors that structure diets and how predation changes due to environment can yield more representative, and potentially more accurate biomass projections and recommendations for the GOA and likely many other managed marine ecosystems. Close

• 82. [Article] Obligations to Protect Marine Ecosystems Under International Conventions and other Legal Instruments

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Obligations to Protect Marine Ecosystems Under International Conventions and other Legal Instruments Author: Aqorau, Transform Research Paper Title: Obligations to Protect Marine Ecosystems Under International Conventions and other Legal Instruments Author: Aqorau, Transform Research Paper Close

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

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

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

• 84. [Article] Evaluation of Integrated Ecological-Economic Models - What are they used for?

  presentation

  Citation × Citation Citation Abstract Copy Title: Evaluation of Integrated Ecological-Economic Models - What are they used for? Author: Schmidt, Jörn, Holland, Dan, Amboage, Rosa Mato, Nielsen, J. Rasmus, Thunberg, Eric, Bastardie, Francois presentation Title: Evaluation of Integrated Ecological-Economic Models - What are they used for? Author: Schmidt, Jörn, Holland, Dan, Amboage, Rosa Mato, Nielsen, J. Rasmus, Thunberg, Eric, Bastardie, Francois presentation Close

• 85. [Article] Bridging the Marine–Terrestrial Disconnect to Improve Marine Coastal Zone Science and Management

  Coastal zone ecosystems sit between larger terrestrial and marine environments and, therefore, are strongly affected by processes occurring in both systems. Marine coastal zone systems provide a range ...

  Citation × Citation Citation Abstract Copy Title: Bridging the Marine–Terrestrial Disconnect to Improve Marine Coastal Zone Science and Management Author: Ruttenberg, Benjamin I., Granek, Elise F. Year: 2011 Coastal zone ecosystems sit between larger terrestrial and marine environments and, therefore, are strongly affected by processes occurring in both systems. Marine coastal zone systems provide a range of benefits to humans, and yet many have been significantly degraded as a result of direct and indirect human impacts. Management efforts have been hampered by disconnects both between management and scientific research and across linked marine–terrestrial systems. Management jurisdictions often start or end at the shoreline, and multiple agencies at different levels of government often have overlapping or conflicting management goals or priorities, or suffer from a lack of knowledge or interest. Scientists also often fail to consider connections among linked marine–terrestrial systems, and communication among agencies, among scientists in different disciplines, and between scientists and managers is often inadequate. However, despite the institutional and scientific challenges inherent in improving coastal zone management, there are examples of increased coordination and cooperation among different organizations. We discuss a number of examples— including where the marine–terrestrial and science–management disconnects persist and where better integration has led to successes in coastal zone management—and provide recommendations to scientists and managers on how to better link their efforts in science and management across marine and terrestrial systems. Title: Bridging the Marine–Terrestrial Disconnect to Improve Marine Coastal Zone Science and Management Author: Ruttenberg, Benjamin I., Granek, Elise F. Year: 2011 Coastal zone ecosystems sit between larger terrestrial and marine environments and, therefore, are strongly affected by processes occurring in both systems. Marine coastal zone systems provide a range of benefits to humans, and yet many have been significantly degraded as a result of direct and indirect human impacts. Management efforts have been hampered by disconnects both between management and scientific research and across linked marine–terrestrial systems. Management jurisdictions often start or end at the shoreline, and multiple agencies at different levels of government often have overlapping or conflicting management goals or priorities, or suffer from a lack of knowledge or interest. Scientists also often fail to consider connections among linked marine–terrestrial systems, and communication among agencies, among scientists in different disciplines, and between scientists and managers is often inadequate. However, despite the institutional and scientific challenges inherent in improving coastal zone management, there are examples of increased coordination and cooperation among different organizations. We discuss a number of examples— including where the marine–terrestrial and science–management disconnects persist and where better integration has led to successes in coastal zone management—and provide recommendations to scientists and managers on how to better link their efforts in science and management across marine and terrestrial systems. Close

• 86. [Article] New approach for using remotely sensed chlorophyll a to identify seabird hotspots

  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/.

  Citation × Citation Citation Abstract Copy Title: New approach for using remotely sensed chlorophyll a to identify seabird hotspots Author: Suryan, Robert M., Santora, Jarrod A., Sydeman, William J. 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/. Title: New approach for using remotely sensed chlorophyll a to identify seabird hotspots Author: Suryan, Robert M., Santora, Jarrod A., Sydeman, William J. 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/. Close

• 87. [Article] Development of a Marine Strategy for Qeshm Island

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Development of a Marine Strategy for Qeshm Island Author: Shallard, Bruce Research Paper Title: Development of a Marine Strategy for Qeshm Island Author: Shallard, Bruce Research Paper Close

• 88. [Article] Opportunities and challenges in engaging stakeholders in marine reserves planning in Oregon

  This paper explores the contributions of social capital, social connections, and stakeholder engagement to the goals of ecosystem-based management in a local scale marine planning process. The body of ...

  Citation × Citation Citation Abstract Copy Title: Opportunities and challenges in engaging stakeholders in marine reserves planning in Oregon Author: Bird, Arwen This paper explores the contributions of social capital, social connections, and stakeholder engagement to the goals of ecosystem-based management in a local scale marine planning process. The body of work presented here, through a journal article and report, uses the lens of social capital to evaluate stakeholder engagement in making recommendations for marine reserves through a community team process. In 2010, stakeholders were convened through a community team process to make recommendations for three potential marine reserves in Oregon. In 2012, Oregon Department of Fish and Wildlife contracted with Oregon State University to conduct a rapid evaluation of the stakeholders engaged in that process. Stakeholders on each community team (CT) were surveyed using a web-based questionnaire; 70 (n=70) out of 96 participated in the rapid evaluation. The evaluation report assessed aspects of marine governance, including decision-making, meeting management, and team formation and makes recommendations to improve future processes. Data gathered through the survey was then reviewed using a social capital framework to explore the research question: how does social capital enhance or detract from the goals of marine ecosystem based management (MEBM) in local level marine planning processes? Results indicated that connectivity was enhanced during the CT process. Due to the dualistic nature of social capital, information sharing was both enhanced and detracted during the CT process. Respondents’ comments regarding power dynamics, through the operation of linking capital, between the CTs, nongovernmental organizations, and state entities are discussed relative to the influence these dynamics had on marine reserves planning overall and on the CT process in Oregon. Title: Opportunities and challenges in engaging stakeholders in marine reserves planning in Oregon Author: Bird, Arwen This paper explores the contributions of social capital, social connections, and stakeholder engagement to the goals of ecosystem-based management in a local scale marine planning process. The body of work presented here, through a journal article and report, uses the lens of social capital to evaluate stakeholder engagement in making recommendations for marine reserves through a community team process. In 2010, stakeholders were convened through a community team process to make recommendations for three potential marine reserves in Oregon. In 2012, Oregon Department of Fish and Wildlife contracted with Oregon State University to conduct a rapid evaluation of the stakeholders engaged in that process. Stakeholders on each community team (CT) were surveyed using a web-based questionnaire; 70 (n=70) out of 96 participated in the rapid evaluation. The evaluation report assessed aspects of marine governance, including decision-making, meeting management, and team formation and makes recommendations to improve future processes. Data gathered through the survey was then reviewed using a social capital framework to explore the research question: how does social capital enhance or detract from the goals of marine ecosystem based management (MEBM) in local level marine planning processes? Results indicated that connectivity was enhanced during the CT process. Due to the dualistic nature of social capital, information sharing was both enhanced and detracted during the CT process. Respondents’ comments regarding power dynamics, through the operation of linking capital, between the CTs, nongovernmental organizations, and state entities are discussed relative to the influence these dynamics had on marine reserves planning overall and on the CT process in Oregon. Close

• 89. [Article] Alaska SeaLife Center guide to marine life : for visitors, staff, and all marine life enthusiasts

  This was originally published in 2006 by the Alaska SeaLife Center (http://www.alaskasealife.org/) as a CD. Partial funding for the project was provided by Alaska Sea Grant.

  Citation × Citation Citation Abstract Copy Title: Alaska SeaLife Center guide to marine life : for visitors, staff, and all marine life enthusiasts Author: Hansen, Gayle I., Uscian, John M. This was originally published in 2006 by the Alaska SeaLife Center (http://www.alaskasealife.org/) as a CD. Partial funding for the project was provided by Alaska Sea Grant. Title: Alaska SeaLife Center guide to marine life : for visitors, staff, and all marine life enthusiasts Author: Hansen, Gayle I., Uscian, John M. This was originally published in 2006 by the Alaska SeaLife Center (http://www.alaskasealife.org/) as a CD. Partial funding for the project was provided by Alaska Sea Grant. Close

• 90. [Article] Securing ocean benefits for society in the face of climate change

  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: Securing ocean benefits for society in the face of climate change Author: Hollowed, A.B., Gaines, S.D., Talley, L.D., Ruckelshaus, M., Rabalais, N.N., Knowlton, N., Sydeman, W.J., Duffy, J.E., Grebmeier, J.M., Doney, S.C., Barry, J.P., Galindo, H.M., Polovina, J., English, C.A., Chan, F. 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: Securing ocean benefits for society in the face of climate change Author: Hollowed, A.B., Gaines, S.D., Talley, L.D., Ruckelshaus, M., Rabalais, N.N., Knowlton, N., Sydeman, W.J., Duffy, J.E., Grebmeier, J.M., Doney, S.C., Barry, J.P., Galindo, H.M., Polovina, J., English, C.A., Chan, F. 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