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• 21. [Article] Landscape features affecting genetic diversity and structure in East African ungulate species

  Habitat loss and fragmentation is a crisis affecting wildlife worldwide. In Tanzania, East Africa, a dramatic and recent (<80 years) expansion in human settlement and agriculture threatens to reduce gene ...

  Citation × Citation Citation Abstract Copy Title: Landscape features affecting genetic diversity and structure in East African ungulate species Author: Crowhurst, Rachel Selena Habitat loss and fragmentation is a crisis affecting wildlife worldwide. In Tanzania, East Africa, a dramatic and recent (<80 years) expansion in human settlement and agriculture threatens to reduce gene flow among protected areas for many species of large mammals. Wildlife linkages can mitigate population isolation, but linkage designs lacking empirical justification may be controversial and ineffective. Connectivity conservation requires an understanding of how biogeographic factors shaped gene flow prior to habitat loss or fragmentation, however the history of interaction among populations is rarely known. The goal of my study was to provide context for connectivity conservation in central and southern Tanzania by identifying landscape features that have shaped gene flow for three ungulate species with different dispersal capabilities. I investigated historical patterns of connectivity for Maasai giraffe (Giraffa camelopardalis tippelskirchi), impala (Aepyceros melampus), and eland (Tragelaphus oryx) by estimating genetic structure among four to eight protected areas per species. Genetic structure changes very slowly among large populations and thus is likely to reflect historical processes instead of recent anthropogenic influences. I collected noninvasive DNA samples and generated microsatellite genotypes at 8 to 15 loci per species, then estimated genetic diversity metrics (allelic richness, AR, and expected heterozygosity, H[subscript E]) for each population (defined by reserve). I also calculated genetic distance (F[subscript ST] and Nei's unbiased genetic distance, D[subscript hat]) and an estimate of gene flow (Nm) between all population pairs for each species. To elucidate the possible causes of genetic structure between these populations, I tested for isolation by distance and isolation by resistance based on a suite of biogeographic factors hypothesized to affect gene flow. To do this, I created GIS-based resistance surfaces that assigned different costs of movement to landscape features. I created one or more resistance surfaces for each hypothesis of landscape effect. I used circuit theory to estimate the cumulative resistance between each pair of reserves for each weighting scheme, and then performed Mantel tests to calculate the correlation between these resistances and the observed population pairwise genetic distances (D[subscript hat]). I chose the optimal resistance model for each species as the model that was most highly correlated with observed genetic patterns. To verify that the correlation of resistance models with genetic distance was not an artefact of geographic distance, I performed partial Mantel tests to calculate correlation while controlling for the effect of geographic distance. Finally, I compared historical gene flow patterns to the distribution of contemporary human activity to predict areas that are at risk of a loss of connectivity. Indices of genetic diversity were moderate for all three species and comparable to previously reported values for other savannah ungulates. Diversity (both H[subscript E] and A[subscript R]) was highest in eland and lowest in giraffe for these populations, and was not consistently correlated with reserve size as has been reported for other species in East Africa. Although patterns in genetic distance were broadly similar across all three species there were also striking differences in connectivity, highlighting the importance of cross-species comparisons in connectivity conservation. At this scale, resistance models based on slope strongly predicted population structure for all three species; distance to water was also highly correlated with genetic distance in eland. For all three species, the greatest genetic distances occurred between populations separated by the Eastern Arc Mountains, suggesting that the topography of this area has long acted as a barrier to gene flow, but this effect is present in varying degrees for each species. I observed high levels of historical gene flow between centrally located populations (Ruaha National Park and Rungwa Game Reserve) and those in the southwest (Katavi National Park and Rukwa Game Reserve). Although human settlement in this area has been low relative to other areas, the connection between the Katavi/Rukwa and Ruaha ecosystems may be threatened by increased human activity and warrants conservation. High levels of historical gene flow were also seen between reserves in the northeast (Tarangire National Park, Swagaswaga Game Reserve) and the central and southwest populations. These connections appear highly threatened due to current land use practices, and may have already suffered a loss of gene flow. Field surveys in the lands surrounding the northeastern reserves are needed to quantify current levels of connectivity and determine whether corridors could be established to maintain or restore gene flow with other reserves. Title: Landscape features affecting genetic diversity and structure in East African ungulate species Author: Crowhurst, Rachel Selena Habitat loss and fragmentation is a crisis affecting wildlife worldwide. In Tanzania, East Africa, a dramatic and recent (<80 years) expansion in human settlement and agriculture threatens to reduce gene flow among protected areas for many species of large mammals. Wildlife linkages can mitigate population isolation, but linkage designs lacking empirical justification may be controversial and ineffective. Connectivity conservation requires an understanding of how biogeographic factors shaped gene flow prior to habitat loss or fragmentation, however the history of interaction among populations is rarely known. The goal of my study was to provide context for connectivity conservation in central and southern Tanzania by identifying landscape features that have shaped gene flow for three ungulate species with different dispersal capabilities. I investigated historical patterns of connectivity for Maasai giraffe (Giraffa camelopardalis tippelskirchi), impala (Aepyceros melampus), and eland (Tragelaphus oryx) by estimating genetic structure among four to eight protected areas per species. Genetic structure changes very slowly among large populations and thus is likely to reflect historical processes instead of recent anthropogenic influences. I collected noninvasive DNA samples and generated microsatellite genotypes at 8 to 15 loci per species, then estimated genetic diversity metrics (allelic richness, AR, and expected heterozygosity, H[subscript E]) for each population (defined by reserve). I also calculated genetic distance (F[subscript ST] and Nei's unbiased genetic distance, D[subscript hat]) and an estimate of gene flow (Nm) between all population pairs for each species. To elucidate the possible causes of genetic structure between these populations, I tested for isolation by distance and isolation by resistance based on a suite of biogeographic factors hypothesized to affect gene flow. To do this, I created GIS-based resistance surfaces that assigned different costs of movement to landscape features. I created one or more resistance surfaces for each hypothesis of landscape effect. I used circuit theory to estimate the cumulative resistance between each pair of reserves for each weighting scheme, and then performed Mantel tests to calculate the correlation between these resistances and the observed population pairwise genetic distances (D[subscript hat]). I chose the optimal resistance model for each species as the model that was most highly correlated with observed genetic patterns. To verify that the correlation of resistance models with genetic distance was not an artefact of geographic distance, I performed partial Mantel tests to calculate correlation while controlling for the effect of geographic distance. Finally, I compared historical gene flow patterns to the distribution of contemporary human activity to predict areas that are at risk of a loss of connectivity. Indices of genetic diversity were moderate for all three species and comparable to previously reported values for other savannah ungulates. Diversity (both H[subscript E] and A[subscript R]) was highest in eland and lowest in giraffe for these populations, and was not consistently correlated with reserve size as has been reported for other species in East Africa. Although patterns in genetic distance were broadly similar across all three species there were also striking differences in connectivity, highlighting the importance of cross-species comparisons in connectivity conservation. At this scale, resistance models based on slope strongly predicted population structure for all three species; distance to water was also highly correlated with genetic distance in eland. For all three species, the greatest genetic distances occurred between populations separated by the Eastern Arc Mountains, suggesting that the topography of this area has long acted as a barrier to gene flow, but this effect is present in varying degrees for each species. I observed high levels of historical gene flow between centrally located populations (Ruaha National Park and Rungwa Game Reserve) and those in the southwest (Katavi National Park and Rukwa Game Reserve). Although human settlement in this area has been low relative to other areas, the connection between the Katavi/Rukwa and Ruaha ecosystems may be threatened by increased human activity and warrants conservation. High levels of historical gene flow were also seen between reserves in the northeast (Tarangire National Park, Swagaswaga Game Reserve) and the central and southwest populations. These connections appear highly threatened due to current land use practices, and may have already suffered a loss of gene flow. Field surveys in the lands surrounding the northeastern reserves are needed to quantify current levels of connectivity and determine whether corridors could be established to maintain or restore gene flow with other reserves. Close

• 22. [Article] Broad-scale patterns of invertebrate richness and community composition in temporary rivers: effects of flow intermittence

  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 John Wiley ...

  Citation × Citation Citation Abstract Copy Title: Broad-scale patterns of invertebrate richness and community composition in temporary rivers: effects of flow intermittence Author: Larned, S. T., Bogan, M. T., Wood, P. J., Santos, A. N., Meyer, E. I., Datry, T., Fritz, K. M. 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 John Wiley & Sons, Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1600-0587. Title: Broad-scale patterns of invertebrate richness and community composition in temporary rivers: effects of flow intermittence Author: Larned, S. T., Bogan, M. T., Wood, P. J., Santos, A. N., Meyer, E. I., Datry, T., Fritz, K. M. 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 John Wiley & Sons, Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1600-0587. Close

• 23. [Article] Intercomparison of MODIS albedo retrievals and in situ measurements across the global FLUXNET network

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment/#description. To the best of our ...

  Citation × Citation Citation Abstract Copy Title: Intercomparison of MODIS albedo retrievals and in situ measurements across the global FLUXNET network Author: Yang, Xiaoyuan, Vannan, Suresh K. Santhana, Law, Beverly E., Richardson, Andrew D., Roman, Miguel O., Moors, Eddy, Matteucci, Giorgio, Migliavacca, Mirco, Seufert, Guenther, Ciais, Philippe, Cook, Robert B., Schaaf, Crystal B., Pan, Jerry Yun, Cescatti, Alessandro, Marcolla, Barbara This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment/#description. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Intercomparison of MODIS albedo retrievals and in situ measurements across the global FLUXNET network Author: Yang, Xiaoyuan, Vannan, Suresh K. Santhana, Law, Beverly E., Richardson, Andrew D., Roman, Miguel O., Moors, Eddy, Matteucci, Giorgio, Migliavacca, Mirco, Seufert, Guenther, Ciais, Philippe, Cook, Robert B., Schaaf, Crystal B., Pan, Jerry Yun, Cescatti, Alessandro, Marcolla, Barbara This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment/#description. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 24. [Article] The Icelandic Pelagic Sector and its Development under an ITQ Management System

  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 Icelandic Pelagic Sector and its Development under an ITQ Management System Author: Saevaldsson, Hordur, Gunnlaugsson, Stefan B. 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 Icelandic Pelagic Sector and its Development under an ITQ Management System Author: Saevaldsson, Hordur, Gunnlaugsson, Stefan B. 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

• 25. [Article] Analyzing the transmission of wildfire exposure on a fire-prone landscape in Oregon, USA

  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: Analyzing the transmission of wildfire exposure on a fire-prone landscape in Oregon, USA Author: Ager, Alan A., Vaillant, Nicole M., Finney, Mark A., Vance-Borland, Ken, Day, Michelle A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management. Title: Analyzing the transmission of wildfire exposure on a fire-prone landscape in Oregon, USA Author: Ager, Alan A., Vaillant, Nicole M., Finney, Mark A., Vance-Borland, Ken, Day, Michelle A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management. Close

• 26. [Article] Sex-biased dispersal in a rare butterfly and the implications for its conservation

  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 Springer ...

  Citation × Citation Citation Abstract Copy Title: Sex-biased dispersal in a rare butterfly and the implications for its conservation Author: Bennett, Victoria J., Smith, Winston P., Pack, Shalynn M., Betts, Matthew G. 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 Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Title: Sex-biased dispersal in a rare butterfly and the implications for its conservation Author: Bennett, Victoria J., Smith, Winston P., Pack, Shalynn M., Betts, Matthew G. 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 Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Close

• 27. [Article] How sweet is the land? Modeling caloric landscapes for tropical hummingbirds

  Pollination is a critical ecosystem function for sustaining biodiversity. However, pollinators and the services they provide are threatened by landscape-altering anthropogenic activities across the globe. ...

  Citation × Citation Citation Abstract Copy Title: How sweet is the land? Modeling caloric landscapes for tropical hummingbirds Author: Birkett, Christina Nozomi Pollination is a critical ecosystem function for sustaining biodiversity. However, pollinators and the services they provide are threatened by landscape-altering anthropogenic activities across the globe. Habitat loss and fragmentation, introduction of invasive species, chemical use, and urbanization have been shown to impact pollination. Pollinator foraging behavior is thought to be largely a function of available floral rewards, therefore, understanding the role of resource distributions in pollinator abundance and behavior within disturbed landscapes is a key piece of information for conservation. Fine scale information on floral resource distribution across disturbed landscapes is lacking in most systems. Here we demonstrate how existing presence-only species distribution modeling techniques (i.e., Maximum entropy modeling [MaxEnt]) can be combined with widely available environmental information to create resource landscapes for both pollinator communities and specific pollinators of interest. This model is the first of its kind, making possible simultaneous visualization of fine-scale resource configuration and quantity across abroad spatial extent. We tested this method to build caloric landscapes using tropical hummingbird-plant system in Costa Rica. We found that our MaxEnt models performed well on independent data for all 13 flower species we examined. Our landscape-scale caloric map showed that available calories within each 35m² pixel ranged from 0 to greater than 30,000 across our study region. Our model provides the possibility of predicting pollinator movement and abundance based upon resource supply. As its parameters are flexible, it is broad in its potential applications. The flexibility in calibration to desired resource landscapes permits applying the model to other pollinator-plant systems. We hope that this model will complement the current ecologist’s toolbox, aiding in ensuring the continuation and health of pollinator systems. Title: How sweet is the land? Modeling caloric landscapes for tropical hummingbirds Author: Birkett, Christina Nozomi Pollination is a critical ecosystem function for sustaining biodiversity. However, pollinators and the services they provide are threatened by landscape-altering anthropogenic activities across the globe. Habitat loss and fragmentation, introduction of invasive species, chemical use, and urbanization have been shown to impact pollination. Pollinator foraging behavior is thought to be largely a function of available floral rewards, therefore, understanding the role of resource distributions in pollinator abundance and behavior within disturbed landscapes is a key piece of information for conservation. Fine scale information on floral resource distribution across disturbed landscapes is lacking in most systems. Here we demonstrate how existing presence-only species distribution modeling techniques (i.e., Maximum entropy modeling [MaxEnt]) can be combined with widely available environmental information to create resource landscapes for both pollinator communities and specific pollinators of interest. This model is the first of its kind, making possible simultaneous visualization of fine-scale resource configuration and quantity across abroad spatial extent. We tested this method to build caloric landscapes using tropical hummingbird-plant system in Costa Rica. We found that our MaxEnt models performed well on independent data for all 13 flower species we examined. Our landscape-scale caloric map showed that available calories within each 35m² pixel ranged from 0 to greater than 30,000 across our study region. Our model provides the possibility of predicting pollinator movement and abundance based upon resource supply. As its parameters are flexible, it is broad in its potential applications. The flexibility in calibration to desired resource landscapes permits applying the model to other pollinator-plant systems. We hope that this model will complement the current ecologist’s toolbox, aiding in ensuring the continuation and health of pollinator systems. Close

• 28. [Article] Microbial community structure and dynamics in restored subtropical seagrass sediments

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

  Citation × Citation Citation Abstract Copy Title: Microbial community structure and dynamics in restored subtropical seagrass sediments Author: Fourqurean, James W., Bourque, Amanda S., Vega-Thurber, Rebecca To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/journals/ame/ame-home/. Title: Microbial community structure and dynamics in restored subtropical seagrass sediments Author: Fourqurean, James W., Bourque, Amanda S., Vega-Thurber, Rebecca To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Inter-Research and can be found at: http://www.int-res.com/journals/ame/ame-home/. Close

• 29. [Article] Comparing Himalayan blackberry (Rubus armeniacus) management techniques in upland prairie communities of the W.L. Finley National Wildlife Refuge

  Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the ...

  Citation × Citation Citation Abstract Copy Title: Comparing Himalayan blackberry (Rubus armeniacus) management techniques in upland prairie communities of the W.L. Finley National Wildlife Refuge Author: Ensley, Jona L. Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the last remaining upland prairies once prevalent throughout Oregon's Willamette Valley. More than a century of land fragmentation, fire suppression, and cultivation has shifted species composition and physical structure of the native prairies toward woodland ecosystems, reducing habitat quality and quantity. This transition is greatly driven by the encroachment and introduction of the non-native, woody invader Himalayan blackberry (Rubus armeniacus). This study focused on the three most common Himalayan blackberry management techniques used within the refuge's upland prairies: late summer mowing, late summer burning, and a combination of both. The goal was to analyze the efficacy of each technique in meeting the refuge objectives of controlling Himalayan blackberry populations and promoting native prairie physiognomy after one application using a complete random block design. Findings were presented to refuge managers to facilitate improved management of these fragile communities. Mowing was found to have the greatest reduction in blackberry stem and plant density and resulted in the lowest resprout density post-treatment. This treatment also met the refuge objectives of reducing woody cover and increasing graminoid cover, but did little to increase herbaceous cover when compared to the control group. Burning produced no significant increase in herbaceous cover or reduction in woody cover and provided favorable conditions for Himalayan blackberry seedling germination, contributing to a larger blackberry problem in years to come. In promoting herbaceous habitat for upland-dependent species, mowing with subsequent burning was the most successful technique. Though not as effective in reducing blackberry vigor as mowing alone, this treatment showed the most potential of the three in managing for all objectives. Title: Comparing Himalayan blackberry (Rubus armeniacus) management techniques in upland prairie communities of the W.L. Finley National Wildlife Refuge Author: Ensley, Jona L. Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the last remaining upland prairies once prevalent throughout Oregon's Willamette Valley. More than a century of land fragmentation, fire suppression, and cultivation has shifted species composition and physical structure of the native prairies toward woodland ecosystems, reducing habitat quality and quantity. This transition is greatly driven by the encroachment and introduction of the non-native, woody invader Himalayan blackberry (Rubus armeniacus). This study focused on the three most common Himalayan blackberry management techniques used within the refuge's upland prairies: late summer mowing, late summer burning, and a combination of both. The goal was to analyze the efficacy of each technique in meeting the refuge objectives of controlling Himalayan blackberry populations and promoting native prairie physiognomy after one application using a complete random block design. Findings were presented to refuge managers to facilitate improved management of these fragile communities. Mowing was found to have the greatest reduction in blackberry stem and plant density and resulted in the lowest resprout density post-treatment. This treatment also met the refuge objectives of reducing woody cover and increasing graminoid cover, but did little to increase herbaceous cover when compared to the control group. Burning produced no significant increase in herbaceous cover or reduction in woody cover and provided favorable conditions for Himalayan blackberry seedling germination, contributing to a larger blackberry problem in years to come. In promoting herbaceous habitat for upland-dependent species, mowing with subsequent burning was the most successful technique. Though not as effective in reducing blackberry vigor as mowing alone, this treatment showed the most potential of the three in managing for all objectives. Close

• 30. [Article] Assessing the Current State of Transboundary Cooperation in the International Columbia River Basin

  The Columbia River Treaty (CRT) is often used as an example of how treaties can work to normalize, regulate, and improve the cooperative management of shared water resources between basin countries. Few ...

  Citation × Citation Citation Abstract Copy Title: Assessing the Current State of Transboundary Cooperation in the International Columbia River Basin Author: Timboe, Ingrid A. The Columbia River Treaty (CRT) is often used as an example of how treaties can work to normalize, regulate, and improve the cooperative management of shared water resources between basin countries. Few would argue that, in its limited mandate to regulate hydropower generation and flood risk management for downstream communities, the CRT has been anything but a success. However, there are many aspects of water resource management, including water quality, aquatic species, and indigenous peoples' rights and responsibilities that are left unaddressed by the Treaty. These issues are of increasing importance to managers and stakeholders in river basins around the world. This paper asks, in the absence of a formal agreement governing these issues, are the United States and Canada coordinating the broader management of the Columbia River and its international tributaries? If so, around which water resource issues do they collaborate and at what level? If not, do these gaps in co-management negatively affect the basin? In order to assess the current state of transboundary water cooperation between the United States and Canada within the basin, 50 transboundary initiatives were identified and categorized into management categories including: ecosystem function, fish passage & habitat, climate change, invasive species or toxics management, and energy. Interviews were then conducted with 34 natural resource managers throughout the international basin on their work with these initiatives, specifically addressing areas where they are, and are not, collaborating at this time. The interviews revealed that, while there is a great deal of collaborative work being done, it appears largely fragmented and restricted to sub-basin activities. International, basin-wide cooperation, outside of treaty obligations under the CRT, appears limited at this time. This thesis contends that there is a need for these sub-basin activities to be networked with one another, either through the Treaty, or through an inclusive, legitimate, and transparent river basin organization. Title: Assessing the Current State of Transboundary Cooperation in the International Columbia River Basin Author: Timboe, Ingrid A. The Columbia River Treaty (CRT) is often used as an example of how treaties can work to normalize, regulate, and improve the cooperative management of shared water resources between basin countries. Few would argue that, in its limited mandate to regulate hydropower generation and flood risk management for downstream communities, the CRT has been anything but a success. However, there are many aspects of water resource management, including water quality, aquatic species, and indigenous peoples' rights and responsibilities that are left unaddressed by the Treaty. These issues are of increasing importance to managers and stakeholders in river basins around the world. This paper asks, in the absence of a formal agreement governing these issues, are the United States and Canada coordinating the broader management of the Columbia River and its international tributaries? If so, around which water resource issues do they collaborate and at what level? If not, do these gaps in co-management negatively affect the basin? In order to assess the current state of transboundary water cooperation between the United States and Canada within the basin, 50 transboundary initiatives were identified and categorized into management categories including: ecosystem function, fish passage & habitat, climate change, invasive species or toxics management, and energy. Interviews were then conducted with 34 natural resource managers throughout the international basin on their work with these initiatives, specifically addressing areas where they are, and are not, collaborating at this time. The interviews revealed that, while there is a great deal of collaborative work being done, it appears largely fragmented and restricted to sub-basin activities. International, basin-wide cooperation, outside of treaty obligations under the CRT, appears limited at this time. This thesis contends that there is a need for these sub-basin activities to be networked with one another, either through the Treaty, or through an inclusive, legitimate, and transparent river basin organization. Close