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• 51. [Article] Damage to Helianthus Species by “Ironweed” Weevils

  Proceedings of the 73rd Annual Pacific Northwest Insect Management Conference, held January 6-7, 2014 at the Hilton Hotel, Portland, Oregon.

  Citation × Citation Citation Abstract Copy Title: Damage to Helianthus Species by “Ironweed” Weevils Author: Bragg, David E. Year: 2014 Proceedings of the 73rd Annual Pacific Northwest Insect Management Conference, held January 6-7, 2014 at the Hilton Hotel, Portland, Oregon. Title: Damage to Helianthus Species by “Ironweed” Weevils Author: Bragg, David E. Year: 2014 Proceedings of the 73rd Annual Pacific Northwest Insect Management Conference, held January 6-7, 2014 at the Hilton Hotel, Portland, Oregon. Close

• 52. [Article] Environmental DNA (eDNA) Detects the Invasive Crayfishes Orconectes rusticus and Pacifastacus leniusculus in Large Lakes of North America

  We report results of a study that made reciprocal comparisons of environmental DNA (eDNA) assays for two major invasive crayfishes between their disparate invasive ranges in North America. Specifically, ...

  Citation × Citation Citation Abstract Copy Title: Environmental DNA (eDNA) Detects the Invasive Crayfishes Orconectes rusticus and Pacifastacus leniusculus in Large Lakes of North America Author: Larson, Eric R., Renshaw, Mark A., Gantz, Crysta A., Umek, John, Chandra, Sudeep, Lodge, David M., Egan, Scott P. Year: 2017 We report results of a study that made reciprocal comparisons of environmental DNA (eDNA) assays for two major invasive crayfishes between their disparate invasive ranges in North America. Specifically, we tested for range expansions of the signal crayfish Pacifastacus leniusculus (Dana, 1852) into the Laurentian Great Lakes region known to be invaded by the rusty crayfish Orconectes rusticus (Girard, 1852), as well as for the invasion of O. rusticus into large lakes of California and Nevada, US known to be invaded by P. leniusculus. We compared eDNA detections to historic localities for O. rusticus within the Great Lakes, and to recent sampling for presence/absence and relative abundance of P. leniusculus in California and Nevada via overnight sets of baited traps. We successfully detected O. rusticus eDNA at six sites from the Great Lakes and P. leniusculus from six of seven lakes where it was known to occur in California and Nevada, but did not detect any range expansions by either species across the North American continent. eDNA appears suitable to detect benthic arthropods from exceptionally large lakes, and will likely be useful in applications for monitoring of new biological invasions into these and other freshwater and marine habitats. Title: Environmental DNA (eDNA) Detects the Invasive Crayfishes Orconectes rusticus and Pacifastacus leniusculus in Large Lakes of North America Author: Larson, Eric R., Renshaw, Mark A., Gantz, Crysta A., Umek, John, Chandra, Sudeep, Lodge, David M., Egan, Scott P. Year: 2017 We report results of a study that made reciprocal comparisons of environmental DNA (eDNA) assays for two major invasive crayfishes between their disparate invasive ranges in North America. Specifically, we tested for range expansions of the signal crayfish Pacifastacus leniusculus (Dana, 1852) into the Laurentian Great Lakes region known to be invaded by the rusty crayfish Orconectes rusticus (Girard, 1852), as well as for the invasion of O. rusticus into large lakes of California and Nevada, US known to be invaded by P. leniusculus. We compared eDNA detections to historic localities for O. rusticus within the Great Lakes, and to recent sampling for presence/absence and relative abundance of P. leniusculus in California and Nevada via overnight sets of baited traps. We successfully detected O. rusticus eDNA at six sites from the Great Lakes and P. leniusculus from six of seven lakes where it was known to occur in California and Nevada, but did not detect any range expansions by either species across the North American continent. eDNA appears suitable to detect benthic arthropods from exceptionally large lakes, and will likely be useful in applications for monitoring of new biological invasions into these and other freshwater and marine habitats. Close

• 53. [Article] Anthropogenic Effects on the Fouling Community: Impacts of Biological Invasions and Anthropogenic Structures on Community Structure

  Coastal anthropogenic infrastructure has significantly modified nearshore environments. Because these structures often have a strong association with shipping as would be found in ports and harbors, they ...

  Citation × Citation Citation Abstract Copy Title: Anthropogenic Effects on the Fouling Community: Impacts of Biological Invasions and Anthropogenic Structures on Community Structure Author: McClees, Whitney Elizabeth Year: 2017 Coastal anthropogenic infrastructure has significantly modified nearshore environments. Because these structures often have a strong association with shipping as would be found in ports and harbors, they have been identified as invasion hotspots. Due to propagule pressure from shipping and recreational boating and suitable uncolonized substrate that provides a refuge from native predators, a greater number of non-native species have been found on these structures compared to nearby natural substrate. The mechanisms that limit the spread of non-native species from anthropogenic structures to natural substrate have been explored for several taxa at a species-specific level, but less so from an overall community perspective. Predation has been identified as one of the biotic interactions limiting invasion success. In addition to predation, dispersal ability may also prevent the spread of non-native species from anthropogenic structures to natural substrate. This thesis addresses how these two mechanisms interact to limit the spread of non-native species from anthropogenic structures to natural substrate and how that alters overall community composition. I aimed to explore differences between communities inside and outside of a marina and determine the extent to which predator and dispersal limitation were structuring these communities. I used a three-factor design, deploying seven unglazed ceramic tiles per each treatment combination of 1) in versus outside a marina in Yaquina Bay, Oregon; 2) cage keeping out predators greater than the mesh size, no cage, or partial cage; 3) fixed near the substrata (benthic) versus suspended 1 meter below the surface. I also transplanted caged, suspended tiles of either adults or recruits from inside the marina to benthic and suspended caging treatments outside of the marina. These tiles allowed me to examine predation when dispersal limitation was not a factor for the community inside the marina, i.e. what happens to both recruits and adults if they can get outside of the marina. I found that the communities inside and outside of the marina were different and the data suggest that both predation and dispersal limitation interact to limit the spread of non-native species. Additionally, I found that mesopredators that could fit through the caging may be influencing predation results and community structure. This research addresses gaps in scientific knowledge regarding the mechanisms that prevent or facilitate the spread of non-native species. Future work could include the further exploration of mesopredation as an important factor in limiting the spread of non-native species and exploring dispersal limitation more in depth as well as broadening the geographic scope to see if the same trends hold true across bays and bioregions. Title: Anthropogenic Effects on the Fouling Community: Impacts of Biological Invasions and Anthropogenic Structures on Community Structure Author: McClees, Whitney Elizabeth Year: 2017 Coastal anthropogenic infrastructure has significantly modified nearshore environments. Because these structures often have a strong association with shipping as would be found in ports and harbors, they have been identified as invasion hotspots. Due to propagule pressure from shipping and recreational boating and suitable uncolonized substrate that provides a refuge from native predators, a greater number of non-native species have been found on these structures compared to nearby natural substrate. The mechanisms that limit the spread of non-native species from anthropogenic structures to natural substrate have been explored for several taxa at a species-specific level, but less so from an overall community perspective. Predation has been identified as one of the biotic interactions limiting invasion success. In addition to predation, dispersal ability may also prevent the spread of non-native species from anthropogenic structures to natural substrate. This thesis addresses how these two mechanisms interact to limit the spread of non-native species from anthropogenic structures to natural substrate and how that alters overall community composition. I aimed to explore differences between communities inside and outside of a marina and determine the extent to which predator and dispersal limitation were structuring these communities. I used a three-factor design, deploying seven unglazed ceramic tiles per each treatment combination of 1) in versus outside a marina in Yaquina Bay, Oregon; 2) cage keeping out predators greater than the mesh size, no cage, or partial cage; 3) fixed near the substrata (benthic) versus suspended 1 meter below the surface. I also transplanted caged, suspended tiles of either adults or recruits from inside the marina to benthic and suspended caging treatments outside of the marina. These tiles allowed me to examine predation when dispersal limitation was not a factor for the community inside the marina, i.e. what happens to both recruits and adults if they can get outside of the marina. I found that the communities inside and outside of the marina were different and the data suggest that both predation and dispersal limitation interact to limit the spread of non-native species. Additionally, I found that mesopredators that could fit through the caging may be influencing predation results and community structure. This research addresses gaps in scientific knowledge regarding the mechanisms that prevent or facilitate the spread of non-native species. Future work could include the further exploration of mesopredation as an important factor in limiting the spread of non-native species and exploring dispersal limitation more in depth as well as broadening the geographic scope to see if the same trends hold true across bays and bioregions. Close

• 54. [Article] Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters

  Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. ...

  Citation × Citation Citation Abstract Copy Title: Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters Author: Strecker, Angela L., Olden, Julian D. Year: 2014 Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. Title: Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters Author: Strecker, Angela L., Olden, Julian D. Year: 2014 Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. Close

• 55. [Article] Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary

  In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Title: Ecosystem Recovery in Estuarine Wetlands of the Columbia River Estuary Author: Kidd, Sarah Ann Year: 2017 In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding. For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower Columbia River of western Oregon, USA, it was hypothesized that native plant species and soil properties would show trends approaching reference levels within 3 to 20 years post-restoration and that lower elevation wetland areas within restored sites would exhibit a greater native species abundance and similarity to reference sites, compared with restored high elevation wetland areas. Results indicated that plant species richness, soil organic matter, bulk density, pH, and salinity conditions among the restoration sites reached reference wetland ranges within 3-6 years post-tidal reconnection. The mid-low marsh elevation zones (2.5 m) remained dominated by non-native species Phalaris arundinacea and Juncus effusus subsp. effusus. To investigate the mechanisms driving these non-native plant invasions, it was hypothesized that native and non-native wetland plant community distributions would be reflective both of their abundance in the seed bank and of their germination tolerance to wetland tidal flooding and salinity conditions. Using a factorial study design of three tidal conditions by three salinity levels, these hypotheses were tested in the greenhouse. Overall, non-native seeds were found to significantly outnumber native seeds in both seed banks. In the greenhouse, P. arundinacea and J. effusus were found to germinate more readily out of the seed bank under freshwater high-marsh flooding (1 hour a day) treatments as compared to oligohaline (3 ppt) mid-low marsh flooding (3-6 hours twice a day) treatments and to brackish salinity (10 ppt) treatments. Dominant native wetland species, Carex lyngbyei and Schoenoplectus lacustris, germination were not found to vary significantly among the treatments (p > 0.10). These results indicate that the salinity and flooding gradients within these restored marshes suppress germination of the non-native species in the low-mid marsh but not in the high marsh, where they are likely able to outcompete the native species due to their dominance in the seed bank. The implications of these results for passive tidal wetland restoration efforts are that both seed bank composition and species-specific tolerances to restored tidal flooding and salinity gradients are key mechanisms driving native and non-native plant community development and resilience. Close

• 56. [Article] Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA

  Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, ...

  Citation × Citation Citation Abstract Copy Title: Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA Author: Dinsmore, Stephen J., Lauten, David J., Castelein, Kathleen J., Gaines, Eleanor P., Stern, Mark A. Year: 2014 Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, USA, to Baja California, Mexico, and in disjunct interior sites. The Pacific coast population is federally listed as Threatened; habitat loss and nest loss to a suite of terrestrial and avian predators are thought to be primary factors limiting population growth in this species. In coastal Oregon, USA, a consortium of state and federal management agencies deployed nest exclosures on active Snowy Plover nests, initiated a lethal predator management program, and conducted local-scale habitat management in an effort to boost local productivity. During 1990–2009, we monitored 1,951 Snowy Plover nests at 9 sites with varying treatments. We examined the effectiveness of 3 types of nest exclosures (large, small, and outfitted with electric wire), predator removal, and habitat management on nest survival. Habitat management to remove invasive grasses and provide more suitable nesting substrate more than doubled nest survival. Predator management or use of any of the 3 types of exclosures also affected nest survival. There appeared to be no additional benefit to using both approaches, but the biological relevance of these findings is unclear because of site differences in treatments applied. Importantly, these management techniques only affected nesting success; their effect on other contributions to population viability (e.g., fledging success) was not correlated with nesting success. This long-term study illustrates the short-term benefits and tradeoffs of using nest exclosures, predator management, and habitat restoration to improve nesting success. Although we gained broader insight into the relative efficacy of common management techniques to improve avian nesting success, we cannot yet determine how improved nest success contributes to population growth. Title: Predator Exclosures, Predator Removal, and Habitat Improvement Increase Nest Success of Snowy Plovers in Oregon, USA Author: Dinsmore, Stephen J., Lauten, David J., Castelein, Kathleen J., Gaines, Eleanor P., Stern, Mark A. Year: 2014 Management to increase reproductive success is commonly used to aid recovery of threatened and endangered species. The Western Snowy Plover (Charadrius nivosus nivosus) breeds from coastal Washington, USA, to Baja California, Mexico, and in disjunct interior sites. The Pacific coast population is federally listed as Threatened; habitat loss and nest loss to a suite of terrestrial and avian predators are thought to be primary factors limiting population growth in this species. In coastal Oregon, USA, a consortium of state and federal management agencies deployed nest exclosures on active Snowy Plover nests, initiated a lethal predator management program, and conducted local-scale habitat management in an effort to boost local productivity. During 1990–2009, we monitored 1,951 Snowy Plover nests at 9 sites with varying treatments. We examined the effectiveness of 3 types of nest exclosures (large, small, and outfitted with electric wire), predator removal, and habitat management on nest survival. Habitat management to remove invasive grasses and provide more suitable nesting substrate more than doubled nest survival. Predator management or use of any of the 3 types of exclosures also affected nest survival. There appeared to be no additional benefit to using both approaches, but the biological relevance of these findings is unclear because of site differences in treatments applied. Importantly, these management techniques only affected nesting success; their effect on other contributions to population viability (e.g., fledging success) was not correlated with nesting success. This long-term study illustrates the short-term benefits and tradeoffs of using nest exclosures, predator management, and habitat restoration to improve nesting success. Although we gained broader insight into the relative efficacy of common management techniques to improve avian nesting success, we cannot yet determine how improved nest success contributes to population growth. Close

• 57. [Article] Fire-Vegetation Feedbacks and Alternative States: Common Mechanisms of Temperate Forest Vulnerability to Fire in Southern South America and New Zealand

  In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests ...

  Citation × Citation Citation Abstract Copy Title: Fire-Vegetation Feedbacks and Alternative States: Common Mechanisms of Temperate Forest Vulnerability to Fire in Southern South America and New Zealand Author: Kitzberger, T, Perry, G. L.W., Paritsis, J., Gowda, J. H. Year: 2016 In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests to conversion to pyrophytic non-forest vegetation in southern South America and New Zealand. We extensively review the relevant literature to reveal how these temperate southern hemisphere floras have generated similar positive fire–vegetation feedback mechanisms resulting in increased vulnerability to anthropogenically altered fire regimens. For the two regions, we address the following questions. 1. What are the major plant species, physiognomic types and functional types characteristic of pyrophytic versus pyrophobic vegetation types and how do their traits affect flammability, resistance to fire and recovery after fire? 2. What are the roles of herbivory and microclimate in enhancing fire–vegetation feedbacks? 3. Are there similarities in trends of cover type transitions in relation to altered fire regimens? 4. How are climate change, land-use trends and the effects of introduced plants and animals affecting the vulnerability of these ecosystems to fire-induced transitions to alternative stable states? Most temperate forests of New Zealand and southern South America evolved under conditions of low fire frequencies so few taxa became adapted to recurrent fire. Current dichotomous landscapes consisting of juxtaposed pyrophobic and pyrophytic vegetation types are the outcome of the expansion of fire-resilient and fire-promoting species associated with the arrival of humans. Despite considerable differences in human history and biogeographic history, the case studies presented here show remarkable parallels in life-history traits of the key pyrophobic taxa, fire–vegetation feedback mechanisms, overall ecosystem responses to anthropogenic alteration of fire regimens, and likely vulnerability to expected global change influences on future fire regimens. Title: Fire-Vegetation Feedbacks and Alternative States: Common Mechanisms of Temperate Forest Vulnerability to Fire in Southern South America and New Zealand Author: Kitzberger, T, Perry, G. L.W., Paritsis, J., Gowda, J. H. Year: 2016 In the context of global warming and increasing impacts of invasive plants and animals, we examine how positive fire–vegetation feedbacks are increasing the vulnerability of pyrophobic temperate forests to conversion to pyrophytic non-forest vegetation in southern South America and New Zealand. We extensively review the relevant literature to reveal how these temperate southern hemisphere floras have generated similar positive fire–vegetation feedback mechanisms resulting in increased vulnerability to anthropogenically altered fire regimens. For the two regions, we address the following questions. 1. What are the major plant species, physiognomic types and functional types characteristic of pyrophytic versus pyrophobic vegetation types and how do their traits affect flammability, resistance to fire and recovery after fire? 2. What are the roles of herbivory and microclimate in enhancing fire–vegetation feedbacks? 3. Are there similarities in trends of cover type transitions in relation to altered fire regimens? 4. How are climate change, land-use trends and the effects of introduced plants and animals affecting the vulnerability of these ecosystems to fire-induced transitions to alternative stable states? Most temperate forests of New Zealand and southern South America evolved under conditions of low fire frequencies so few taxa became adapted to recurrent fire. Current dichotomous landscapes consisting of juxtaposed pyrophobic and pyrophytic vegetation types are the outcome of the expansion of fire-resilient and fire-promoting species associated with the arrival of humans. Despite considerable differences in human history and biogeographic history, the case studies presented here show remarkable parallels in life-history traits of the key pyrophobic taxa, fire–vegetation feedback mechanisms, overall ecosystem responses to anthropogenic alteration of fire regimens, and likely vulnerability to expected global change influences on future fire regimens. Close

• 58. [Article] Interactive Physiological Responses of Nile Tilapia to Salinity- and Temperature-induced Stress: Quantifying the Regulation of Apoptosis and Cell Cycle Arrest in Oreochromis Niloticus

  Nile tilapia provide an ideal model to study the accumulation of climate change-induced stressors due to their habitat in tropical freshwater systems that are susceptible to salt water invasion and temperature ...

  Citation × Citation Citation Abstract Copy Title: Interactive Physiological Responses of Nile Tilapia to Salinity- and Temperature-induced Stress: Quantifying the Regulation of Apoptosis and Cell Cycle Arrest in Oreochromis Niloticus Author: McGuire, Charlee Year: 2017 Nile tilapia provide an ideal model to study the accumulation of climate change-induced stressors due to their habitat in tropical freshwater systems that are susceptible to salt water invasion and temperature fluctuation due to sea level rise. This study investigates the physiological responses of Nile tilapia to salinity- and temperature-induced stress to identify the interactive effects of simultaneous stressors on the cell cycle. Proteins indicative of cell cycle activity and arrest were quantified in the tissues of Nile tilapia exposed to various environmental conditions varying by temperature and salinity. Dot Blotting was utilized to measure Gadd45 while Western Blotting was used to confirm the identity of the protein. Results from previous investigations in the Buckley lab were also utilized to compare the expression patterns of Gadd45 to relevant cell activity proteins p53 and PCNA. Of the three proteins under scrutiny, a significant change in expression of p53 was observed for the interaction of salinity- and temperature- induced stress, while full strength saltwater treatment alone was found to have a significant impact on the expression of p53, Gadd45 and PCNA. These findings can be used in collaboration with existing studies to describe the coordination of apoptotic pathways in Nile tilapia and other non-mammalian species, as well as to create policy on how to conserve this important species effectively both in the wild and in fisheries for aquaculture, commercial and public health initiatives in response to global climate change. Title: Interactive Physiological Responses of Nile Tilapia to Salinity- and Temperature-induced Stress: Quantifying the Regulation of Apoptosis and Cell Cycle Arrest in Oreochromis Niloticus Author: McGuire, Charlee Year: 2017 Nile tilapia provide an ideal model to study the accumulation of climate change-induced stressors due to their habitat in tropical freshwater systems that are susceptible to salt water invasion and temperature fluctuation due to sea level rise. This study investigates the physiological responses of Nile tilapia to salinity- and temperature-induced stress to identify the interactive effects of simultaneous stressors on the cell cycle. Proteins indicative of cell cycle activity and arrest were quantified in the tissues of Nile tilapia exposed to various environmental conditions varying by temperature and salinity. Dot Blotting was utilized to measure Gadd45 while Western Blotting was used to confirm the identity of the protein. Results from previous investigations in the Buckley lab were also utilized to compare the expression patterns of Gadd45 to relevant cell activity proteins p53 and PCNA. Of the three proteins under scrutiny, a significant change in expression of p53 was observed for the interaction of salinity- and temperature- induced stress, while full strength saltwater treatment alone was found to have a significant impact on the expression of p53, Gadd45 and PCNA. These findings can be used in collaboration with existing studies to describe the coordination of apoptotic pathways in Nile tilapia and other non-mammalian species, as well as to create policy on how to conserve this important species effectively both in the wild and in fisheries for aquaculture, commercial and public health initiatives in response to global climate change. Close

• 59. [Article] Climate Change and Land Management Impact Rangeland Condition and Sage-Grouse Habitat in Southeastern Oregon

  Contemporary pressures on sagebrush steppe from climate change, exotic species, wildfire, and land use change threaten rangeland species such as the greater sage-grouse (Centrocercus urophasianus). To ...

  Citation × Citation Citation Abstract Copy Title: Climate Change and Land Management Impact Rangeland Condition and Sage-Grouse Habitat in Southeastern Oregon Author: Creutzburg, Megan K., Henderson, Emilie B., Conklin, David R. Year: 2015 Contemporary pressures on sagebrush steppe from climate change, exotic species, wildfire, and land use change threaten rangeland species such as the greater sage-grouse (Centrocercus urophasianus). To effectively manage sagebrush steppe landscapes for long-term goals, managers need information about the potential impacts of climate change, disturbances, and management activities. We integrated information from a dynamic global vegetation model, a sage-grouse habitat climate envelope model, and a state-and-transition simulation model to project broad-scale vegetation dynamics and potential sage-grouse habitat across 23.5 million acres in southeastern Oregon. We evaluated four climate scenarios, including continuing current climate and three scenarios of global climate change, and three management scenarios, including no management, current management and a sage-grouse habitat restoration scenario. All climate change scenarios projected expansion of moist shrub steppe and contraction of dry shrub steppe, but climate scenarios varied widely in the projected extent of xeric shrub steppe, where hot, dry summer conditions are unfavorable for sage-grouse. Wildfire increased by 26% over the century under current climate due to exotic grass encroachment, and by two- to four-fold across all climate change scenarios as extreme fire years became more frequent. Exotic grasses rapidly expanded in all scenarios as large areas of the landscape initially in semi-degraded condition converted to exotic-dominated systems. Due to the combination of exotic grass invasion, juniper encroachment, and climatic unsuitability for sage-grouse, projected sage-grouse habitat declined in the first several decades, but increased in area under the three climate change scenarios later in the century, as moist shrub steppe increased and rangeland condition improved. Management activities in the model were generally unsuccessful in controlling exotic grass invasion but were effective in slowing woodland expansion. Current levels of restoration treatments were insufficient to prevent some juniper expansion, but increased treatment rates under the restoration scenario maintained juniper near initial levels in priority treatment areas. Our simulations indicate that climate change may have both positive and negative implications for maintaining sage-grouse habitat. Title: Climate Change and Land Management Impact Rangeland Condition and Sage-Grouse Habitat in Southeastern Oregon Author: Creutzburg, Megan K., Henderson, Emilie B., Conklin, David R. Year: 2015 Contemporary pressures on sagebrush steppe from climate change, exotic species, wildfire, and land use change threaten rangeland species such as the greater sage-grouse (Centrocercus urophasianus). To effectively manage sagebrush steppe landscapes for long-term goals, managers need information about the potential impacts of climate change, disturbances, and management activities. We integrated information from a dynamic global vegetation model, a sage-grouse habitat climate envelope model, and a state-and-transition simulation model to project broad-scale vegetation dynamics and potential sage-grouse habitat across 23.5 million acres in southeastern Oregon. We evaluated four climate scenarios, including continuing current climate and three scenarios of global climate change, and three management scenarios, including no management, current management and a sage-grouse habitat restoration scenario. All climate change scenarios projected expansion of moist shrub steppe and contraction of dry shrub steppe, but climate scenarios varied widely in the projected extent of xeric shrub steppe, where hot, dry summer conditions are unfavorable for sage-grouse. Wildfire increased by 26% over the century under current climate due to exotic grass encroachment, and by two- to four-fold across all climate change scenarios as extreme fire years became more frequent. Exotic grasses rapidly expanded in all scenarios as large areas of the landscape initially in semi-degraded condition converted to exotic-dominated systems. Due to the combination of exotic grass invasion, juniper encroachment, and climatic unsuitability for sage-grouse, projected sage-grouse habitat declined in the first several decades, but increased in area under the three climate change scenarios later in the century, as moist shrub steppe increased and rangeland condition improved. Management activities in the model were generally unsuccessful in controlling exotic grass invasion but were effective in slowing woodland expansion. Current levels of restoration treatments were insufficient to prevent some juniper expansion, but increased treatment rates under the restoration scenario maintained juniper near initial levels in priority treatment areas. Our simulations indicate that climate change may have both positive and negative implications for maintaining sage-grouse habitat. Close

• 60. [Article] Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters 2014

  Zebra and quagga mussels (Dreissena polymorpha and D. rostriformis bugensis, respectively) were not detected by Oregon Department of Fish and Wildlife (ODFW) and Portland State University (PSU) during ...

  Citation × Citation Citation Abstract Copy Title: Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters 2014 Author: Wells, Steve W., Sytsma, Mark D. Year: 2015 Zebra and quagga mussels (Dreissena polymorpha and D. rostriformis bugensis, respectively) were not detected by Oregon Department of Fish and Wildlife (ODFW) and Portland State University (PSU) during their early detection sampling in Oregon water bodies during 2014. Six high-risk Oregon water bodies were sampled for planktonic larvae and adult mussels during the August to September period. A total of 37 plankton samples were collected and over 520,000 liters of reservoir/lake water were filtered through 64-μm mesh nets during plankton sample collection. The greatest sampling effort occurred in Emigrant Lake, Lake Billy Chinook, and Prineville Reservoir but sampling also occurred in Howard Prairie Lake, Upper Klamath Lake, and Applegate Reservoir. Non-native invertebrates and macrophytes were opportunistically collected during Dreissena sampling in 2014. Corbicula fluminea (Asian clam) adults were collected in Upper Klamath Lake. Potamopyrgus antipodarum (New Zealand mud snails) were collected in Lake Billy Chinook. Potamogeton crispus (curly leaf pondweed) was collected in Emigrant Lake, Howard Prairie Lake, Lake Billy Chinook, and Upper Klamath Lake. To the authors’ knowledge, the C. fluminea in Upper Klamath Lake represents the first reported detection for these species in this location. Title: Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters 2014 Author: Wells, Steve W., Sytsma, Mark D. Year: 2015 Zebra and quagga mussels (Dreissena polymorpha and D. rostriformis bugensis, respectively) were not detected by Oregon Department of Fish and Wildlife (ODFW) and Portland State University (PSU) during their early detection sampling in Oregon water bodies during 2014. Six high-risk Oregon water bodies were sampled for planktonic larvae and adult mussels during the August to September period. A total of 37 plankton samples were collected and over 520,000 liters of reservoir/lake water were filtered through 64-μm mesh nets during plankton sample collection. The greatest sampling effort occurred in Emigrant Lake, Lake Billy Chinook, and Prineville Reservoir but sampling also occurred in Howard Prairie Lake, Upper Klamath Lake, and Applegate Reservoir. Non-native invertebrates and macrophytes were opportunistically collected during Dreissena sampling in 2014. Corbicula fluminea (Asian clam) adults were collected in Upper Klamath Lake. Potamopyrgus antipodarum (New Zealand mud snails) were collected in Lake Billy Chinook. Potamogeton crispus (curly leaf pondweed) was collected in Emigrant Lake, Howard Prairie Lake, Lake Billy Chinook, and Upper Klamath Lake. To the authors’ knowledge, the C. fluminea in Upper Klamath Lake represents the first reported detection for these species in this location. Close