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• 1. [Article] Onshore-offshore variations in copepod community structure off the Oregon coast during the summer upwelling season

  The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/

  Citation × Citation Citation Abstract Copy Title: Onshore-offshore variations in copepod community structure off the Oregon coast during the summer upwelling season Author: Emmett, Robert L., Morgan, Cheryl A., Peterson, William T. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Title: Onshore-offshore variations in copepod community structure off the Oregon coast during the summer upwelling season Author: Emmett, Robert L., Morgan, Cheryl A., Peterson, William T. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Close

• 2. [Article] Spatiotemporal Drivers of Seabird Distribution at the Pacific Marine Energy Center off Newport, Oregon

  The central Oregon coast was selected as an ideal site for wave energy development and establishment of the Pacific Marine Energy Center (PMEC). PMEC will consist of two nearshore sites, one north (NETS) ...

  Citation × Citation Citation Abstract Copy Title: Spatiotemporal Drivers of Seabird Distribution at the Pacific Marine Energy Center off Newport, Oregon Author: Porquez, Jessica M. The central Oregon coast was selected as an ideal site for wave energy development and establishment of the Pacific Marine Energy Center (PMEC). PMEC will consist of two nearshore sites, one north (NETS) and one south (SETS) of the Yaquina River, Oregon. Our study aims to assess how the development of wave energy sites might impact marine birds. We used vessel-based strip transect surveys to detect spatial and temporal patterns of seabirds during 28 surveys of NETS and SETS from 2013-2015. We also conducted 29 surveys along the Newport Hydrographic Line (NHL) (2006-2009, 2013-2015), a cross-shelf oceanographic sampling line that extends 40 km west of NETS. We collected in situ measurements of surface conductivity, temperature and fluorescence to test correlations between spatial variables and seabird abundance. Common murres (Uria aalge) were the most abundant resident species (70%) while sooty shearwaters (Puffinus griseus) were the most abundant migratory species (78%). We identified 7 focal species (common murres, sooty shearwaters, Brandt's and pelagic cormorants (Phalacrocorax penicillatus and pelagicus), western gull (Larus occidentalis), Cassin's auklet (Ptychoramphus aleuticus), and red-necked phalaropes (Phalaropus lobatus), 5 foraging niches and 3 species of interest for analysis. We used non-metric multidimensional scaling ordinations to assess seasonal shifts in the seabird community at a focal species and foraging group level. Both ordinations depicted strong seasonal gradients with distinct seasonal communities. Focal species were also driven by a distance to shore gradient, while foraging niches were more influenced by foraging type (diving versus surface feeding). The shoreward shift or outward dispersal of species appears driven by a combination of factors, including the diffusion of nearshore concentration of murres and cormorants on Yaquina Head post chick fledging, and the inshore movement of migratory species with the onset of upwelling and greater prey abundance. We employed generalized additive mixed models for the focal species, and tested for correlations with in situ data (salinity, temperature and fluorescence), depth, substrate, season, and a random 'site' effect. We identified correlations between several species and measured oceanographic variables, which indicated species' selection of specific water masses. With Inverse Distance Weighted maps we detected high use zones by sooty shearwaters and common murres outside of both site boundaries, except during the spring and summer, when murres occur densely within the NETS. None of our observed species of concern (brown pelicans (Pelicanus occidentalis), black footed albatrosses (Phoebastria nigiripes) and marbled murrelets, (Brachyramphus marmoratus)) were detected within either site boundary. Rather, pelicans and murrelets were observed inshore of the SETS and south of the NETS, and albatrosses were all detected west of the sites. We observed overall low abundance of focal species within the sites, relative to adjacent areas, although the whole study area appears to be productive foraging habitat used by many species. As a baseline characterization of the seabird community off Newport, this work can help inform citing and permitting processes of similar wave energy test facilities and provide a platform for continued monitoring of seabirds in the area. Title: Spatiotemporal Drivers of Seabird Distribution at the Pacific Marine Energy Center off Newport, Oregon Author: Porquez, Jessica M. The central Oregon coast was selected as an ideal site for wave energy development and establishment of the Pacific Marine Energy Center (PMEC). PMEC will consist of two nearshore sites, one north (NETS) and one south (SETS) of the Yaquina River, Oregon. Our study aims to assess how the development of wave energy sites might impact marine birds. We used vessel-based strip transect surveys to detect spatial and temporal patterns of seabirds during 28 surveys of NETS and SETS from 2013-2015. We also conducted 29 surveys along the Newport Hydrographic Line (NHL) (2006-2009, 2013-2015), a cross-shelf oceanographic sampling line that extends 40 km west of NETS. We collected in situ measurements of surface conductivity, temperature and fluorescence to test correlations between spatial variables and seabird abundance. Common murres (Uria aalge) were the most abundant resident species (70%) while sooty shearwaters (Puffinus griseus) were the most abundant migratory species (78%). We identified 7 focal species (common murres, sooty shearwaters, Brandt's and pelagic cormorants (Phalacrocorax penicillatus and pelagicus), western gull (Larus occidentalis), Cassin's auklet (Ptychoramphus aleuticus), and red-necked phalaropes (Phalaropus lobatus), 5 foraging niches and 3 species of interest for analysis. We used non-metric multidimensional scaling ordinations to assess seasonal shifts in the seabird community at a focal species and foraging group level. Both ordinations depicted strong seasonal gradients with distinct seasonal communities. Focal species were also driven by a distance to shore gradient, while foraging niches were more influenced by foraging type (diving versus surface feeding). The shoreward shift or outward dispersal of species appears driven by a combination of factors, including the diffusion of nearshore concentration of murres and cormorants on Yaquina Head post chick fledging, and the inshore movement of migratory species with the onset of upwelling and greater prey abundance. We employed generalized additive mixed models for the focal species, and tested for correlations with in situ data (salinity, temperature and fluorescence), depth, substrate, season, and a random 'site' effect. We identified correlations between several species and measured oceanographic variables, which indicated species' selection of specific water masses. With Inverse Distance Weighted maps we detected high use zones by sooty shearwaters and common murres outside of both site boundaries, except during the spring and summer, when murres occur densely within the NETS. None of our observed species of concern (brown pelicans (Pelicanus occidentalis), black footed albatrosses (Phoebastria nigiripes) and marbled murrelets, (Brachyramphus marmoratus)) were detected within either site boundary. Rather, pelicans and murrelets were observed inshore of the SETS and south of the NETS, and albatrosses were all detected west of the sites. We observed overall low abundance of focal species within the sites, relative to adjacent areas, although the whole study area appears to be productive foraging habitat used by many species. As a baseline characterization of the seabird community off Newport, this work can help inform citing and permitting processes of similar wave energy test facilities and provide a platform for continued monitoring of seabirds in the area. Close

• 3. [Article] Biological indicators of the timing and direction of warm-water advection during the 1997/1998 El Niño off the central Oregon coast, USA

  The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/

  Citation × Citation Citation Abstract Copy Title: Biological indicators of the timing and direction of warm-water advection during the 1997/1998 El Niño off the central Oregon coast, USA Author: Johnson, Travis B., Morgan, Cheryl A., Keister, Julie E., Peterson, William T. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Title: Biological indicators of the timing and direction of warm-water advection during the 1997/1998 El Niño off the central Oregon coast, USA Author: Johnson, Travis B., Morgan, Cheryl A., Keister, Julie E., Peterson, William T. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Close

• 4. [Article] Fire effects on wetland prairie species: final report

  Project No. 14-48-0001-96749

  Citation × Citation Citation Abstract Copy Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Close

• 5. [Article] Seed viability studies for recovery of Plagiobothrys hirtus (Boraginaceae), the rough popcornflower

  The original submitted file is the .ppt file. The .pdf file was made for preservation purposes.

  Citation × Citation Citation Abstract Copy Title: Seed viability studies for recovery of Plagiobothrys hirtus (Boraginaceae), the rough popcornflower Author: Amsberry, Kelly, Wilson, Courtney, Meinke, Robert J. The original submitted file is the .ppt file. The .pdf file was made for preservation purposes. Title: Seed viability studies for recovery of Plagiobothrys hirtus (Boraginaceae), the rough popcornflower Author: Amsberry, Kelly, Wilson, Courtney, Meinke, Robert J. The original submitted file is the .ppt file. The .pdf file was made for preservation purposes. Close

• 6. [Article] Reviving Whychus Creek: Averting Collisions between the Endangered Species Act and Agricultural Water Use through Proactive Streamflow Restoration

  In the wake of policies catalyzing settlement through agrarian-based land ‘improvement’, private property rights absorbed water resources through Western water law. Consequently, these dominant user regimes ...

  Citation × Citation Citation Abstract Copy Title: Reviving Whychus Creek: Averting Collisions between the Endangered Species Act and Agricultural Water Use through Proactive Streamflow Restoration Author: Dengel, Jeff In the wake of policies catalyzing settlement through agrarian-based land ‘improvement’, private property rights absorbed water resources through Western water law. Consequently, these dominant user regimes and the doctrine of prior appropriation allocated nearly 80 percent of freshwater resources to agricultural use. Following enactment of the Endangered Species Act (ESA) in 1973 agricultural water users and the federal government were set on a collision course, as private property was now subject to regulatory imposition. Within Western states water bodies contiguous to private agrarian lands host the majority of aquatic species listed under the ESA. Of all the effects associated with agricultural water use, streamflow depletion constitutes the primary source of species imperilment. Customary irrigation practices often dewater streams completely or render aquatic habitat inhospitable. Consequently, curtailment of water use is increasingly sought during enforcement of ESA regulations. Encounters between ESA regulation and impositions upon agricultural water use are largely reactionary, litigious, and costly; this begs the question of remedy. Responses attending to the matter indicate collaborative and precautionary measures as prospective solutions. Within the context of streamflow-based habitat modification the answer consistently indicates transactional mechanisms reallocating water to instream use. Due to priority-based allocation developed through the doctrine of prior appropriation acquisition of senior water rights is imperative for streamflow restoration. Within Oregon's Whychus Creek agricultural water users employed a series of water right transactions serving to bolster instream flow to avert ESA regulation. Many of these transactions have been implemented through Oregon's Conserved Water Program; a unique statute providing benefits for the environment and agricultural water users alike. Through these transactions senior water rights have been reallocated to instream use and are being met, resulting in a robust presence of instream flow. Title: Reviving Whychus Creek: Averting Collisions between the Endangered Species Act and Agricultural Water Use through Proactive Streamflow Restoration Author: Dengel, Jeff In the wake of policies catalyzing settlement through agrarian-based land ‘improvement’, private property rights absorbed water resources through Western water law. Consequently, these dominant user regimes and the doctrine of prior appropriation allocated nearly 80 percent of freshwater resources to agricultural use. Following enactment of the Endangered Species Act (ESA) in 1973 agricultural water users and the federal government were set on a collision course, as private property was now subject to regulatory imposition. Within Western states water bodies contiguous to private agrarian lands host the majority of aquatic species listed under the ESA. Of all the effects associated with agricultural water use, streamflow depletion constitutes the primary source of species imperilment. Customary irrigation practices often dewater streams completely or render aquatic habitat inhospitable. Consequently, curtailment of water use is increasingly sought during enforcement of ESA regulations. Encounters between ESA regulation and impositions upon agricultural water use are largely reactionary, litigious, and costly; this begs the question of remedy. Responses attending to the matter indicate collaborative and precautionary measures as prospective solutions. Within the context of streamflow-based habitat modification the answer consistently indicates transactional mechanisms reallocating water to instream use. Due to priority-based allocation developed through the doctrine of prior appropriation acquisition of senior water rights is imperative for streamflow restoration. Within Oregon's Whychus Creek agricultural water users employed a series of water right transactions serving to bolster instream flow to avert ESA regulation. Many of these transactions have been implemented through Oregon's Conserved Water Program; a unique statute providing benefits for the environment and agricultural water users alike. Through these transactions senior water rights have been reallocated to instream use and are being met, resulting in a robust presence of instream flow. Close

• 7. [Article] Surfgrasses (Phyllospadix spp.) as dynamic foundation species for macroinvertebrates along the Oregon coast

  Foundation species are important components of ecosystems because they provide habitat and ameliorate stressful conditions for residents. This thesis considers the role of surfgrasses (Phyllospadix spp.) ...

  Citation × Citation Citation Abstract Copy Title: Surfgrasses (Phyllospadix spp.) as dynamic foundation species for macroinvertebrates along the Oregon coast Author: Moulton, Orissa M. Foundation species are important components of ecosystems because they provide habitat and ameliorate stressful conditions for residents. This thesis considers the role of surfgrasses (Phyllospadix spp.) as dynamic foundation species on the coast of Oregon in two studies. Chapter 2, which presents an observational survey of two Phyllospadix congeners, investigates the ways in which surfgrass morphology and observed oceanographic conditions influence associated macroinvertebrate communities throughout a calendar year. Chapter 3, which presents an experimental manipulation of the system, considers the ways in which macroinvertebrates and surfgrass interact. Surfgrasses (Phyllospadix spp.) are ubiquitous foundation species on the coast of Oregon, USA, protecting resident invertebrates from waves and providing them access to sandy substrate in an otherwise rocky habitat. We investigated whether native congeneric species function similarly by comparing the two species' resident macroinvertebrates, plant morphology, and sediment accretion at three capes that vary in oceanographic conditions. The results showed that while the macroinvertebrate abundance was the same between surfgrass species, species richness, composition, and functional groups varied considerably. P. serrulatus also had fewer tillers, rhizomes, and lower biomass per given area but greater sediment accretion than its congener P. scouleri. There was a large difference in macroinvertebrate abundance among capes, with Cape Perpetua having 2.5-3 times more animals per given area than Cape Foulweather or Cape Blanco. Overall, we found that while the two co-occurring surfgrass congeners provided functionally different habitat for resident macroinvertebrate species, regional oceanographic processes (upwelling, productivity) were more influential in determining the overall abundance and productivity of these highly diverse animal communities. The interaction between surfgrass (P. scouleri) and resident macroinvertebrates may be an example of mutual facilitation if surfgrass provides shelter and macroinvertebrate residents reciprocate with nutrient input. We hypothesized that this positive interaction could vary depending on oceanographic conditions. Sites with intermittent upwelling, low retention of upwelled waters, and high nutrient delivery to the intertidal are often dominated by macroalgae and seagrasses, while sessile invertebrates dominate intermittent upwelling sites with high water higher retention and relatively low nutrient delivery to the intertidal. We expected the positive influence of macroinvertebrates upon surfgrass to be strongest at a site with possible nutrient limitation stress. We used manipulative field experiments to examine the interaction between Phyllospadix and macroinvertebrate residents at sites known to differ in coastal oceanography. Treatments were applied in situ to vary presence/absence of residents and nutrient conditions. Results indicate that the community of macroinvertebrates varies greatly in both abundance and composition between the two sites (ca. three fold higher abundance at Strawberry Hill than at Fogarty Creek), but the amount Phyllospadix habitat available to macroinvertebrates does not vary between the two sites. This variation is therefore driven by something external to local habitat, and is likely related to regional oceanography. Furthermore, there is some evidence that macroinvertebrates do have some positive nutrient effect upon surfgrass productivity. Together, these studies provide critical descriptive information about community structure associated with the Phyllospadix system on the Oregon coast. This work contributes to the ever-increasing body of literature suggesting importance of regional oceanography in structuring coastal communities. Title: Surfgrasses (Phyllospadix spp.) as dynamic foundation species for macroinvertebrates along the Oregon coast Author: Moulton, Orissa M. Foundation species are important components of ecosystems because they provide habitat and ameliorate stressful conditions for residents. This thesis considers the role of surfgrasses (Phyllospadix spp.) as dynamic foundation species on the coast of Oregon in two studies. Chapter 2, which presents an observational survey of two Phyllospadix congeners, investigates the ways in which surfgrass morphology and observed oceanographic conditions influence associated macroinvertebrate communities throughout a calendar year. Chapter 3, which presents an experimental manipulation of the system, considers the ways in which macroinvertebrates and surfgrass interact. Surfgrasses (Phyllospadix spp.) are ubiquitous foundation species on the coast of Oregon, USA, protecting resident invertebrates from waves and providing them access to sandy substrate in an otherwise rocky habitat. We investigated whether native congeneric species function similarly by comparing the two species' resident macroinvertebrates, plant morphology, and sediment accretion at three capes that vary in oceanographic conditions. The results showed that while the macroinvertebrate abundance was the same between surfgrass species, species richness, composition, and functional groups varied considerably. P. serrulatus also had fewer tillers, rhizomes, and lower biomass per given area but greater sediment accretion than its congener P. scouleri. There was a large difference in macroinvertebrate abundance among capes, with Cape Perpetua having 2.5-3 times more animals per given area than Cape Foulweather or Cape Blanco. Overall, we found that while the two co-occurring surfgrass congeners provided functionally different habitat for resident macroinvertebrate species, regional oceanographic processes (upwelling, productivity) were more influential in determining the overall abundance and productivity of these highly diverse animal communities. The interaction between surfgrass (P. scouleri) and resident macroinvertebrates may be an example of mutual facilitation if surfgrass provides shelter and macroinvertebrate residents reciprocate with nutrient input. We hypothesized that this positive interaction could vary depending on oceanographic conditions. Sites with intermittent upwelling, low retention of upwelled waters, and high nutrient delivery to the intertidal are often dominated by macroalgae and seagrasses, while sessile invertebrates dominate intermittent upwelling sites with high water higher retention and relatively low nutrient delivery to the intertidal. We expected the positive influence of macroinvertebrates upon surfgrass to be strongest at a site with possible nutrient limitation stress. We used manipulative field experiments to examine the interaction between Phyllospadix and macroinvertebrate residents at sites known to differ in coastal oceanography. Treatments were applied in situ to vary presence/absence of residents and nutrient conditions. Results indicate that the community of macroinvertebrates varies greatly in both abundance and composition between the two sites (ca. three fold higher abundance at Strawberry Hill than at Fogarty Creek), but the amount Phyllospadix habitat available to macroinvertebrates does not vary between the two sites. This variation is therefore driven by something external to local habitat, and is likely related to regional oceanography. Furthermore, there is some evidence that macroinvertebrates do have some positive nutrient effect upon surfgrass productivity. Together, these studies provide critical descriptive information about community structure associated with the Phyllospadix system on the Oregon coast. This work contributes to the ever-increasing body of literature suggesting importance of regional oceanography in structuring coastal communities. Close

• 8. [Article] The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA

  Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially ...

  Citation × Citation Citation Abstract Copy Title: The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA Author: Zarnetske, Phoebe Lehmann, 1979- Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to study the interactions among invasive ecosystem engineers, physical features, and biological communities, because interactions among vegetation, sediment, and fluids within biophysical feedbacks create and modify distinct physical features. Further, these systems provide important ecosystem services including coastal protection afforded by their natural features. In this dissertation, I investigate the interactions and feedbacks among sand-binding beach grass species (a native, Elymus mollis (Trin.), and two non-natives, Ammophila arenaria (L.) Link and A. breviligulata Fernald), sediment supply, and dune shape along the U.S. Pacific Northwest coast. Dunes dominated by A. arenaria tend to be taller and narrower compared to the shorter, wider dunes dominated by A. breviligulata. These patterns suggest an ecological control on dune shape, and thus, coastal vulnerability to overtopping waves. I investigate the causes and consequences of these patterns with experiments, field observations, and modeling. Specifically, I investigate the relative roles of vegetation and sediment supply in shaping coastal dunes over inter-annual and multi-decadal time scales (Chapter 2), characterize a biophysical feedback between beach grass species growth habit and sediment supply (Chapter 3), uncover the mechanisms leading to beach grass coexistence and whether A. breviligulata can invade and dominate new sections of coastline (Chapter 4), and examine the non-target effects resulting from management actions that remove Ammophila for the recovery of the threatened Western Snowy plover (Charadrius alexandrinus nivosus) (Chapter 5). I found that vegetation and sediment supply play important roles in dune shape changes across inter-annual and multi-decadal time scales (Chapter 2). I determined that a biophysical feedback between the beach grass growth habits and sediment supply results in species-specific differences in sand capture ability, and thus, is a likely explanation for differences in dune shape (Chapter 3). I found that all three beach grass species can coexist across different sediment deposition rates, and that this coexistence is largely mediated by positive direct and indirect species interactions. I further determined that A. breviligulata is capable of invading and dominating the beach grass community in regions where it is currently absent (Chapter 4). Combined, these findings indicate that A. breviligulata is an inferior dune building species as compared to A. arenaria, and suggest that in combination with sediment supply gradients, these species differences ultimately lead to differences in dune shape. Potential further invasions of A. breviligulata into southern regions of the Pacific Northwest may diminish the coastal protection ability of dunes currently dominated by A. arenaria, but this effect could be moderated by the predicted near co-dominance of A. arenaria in these lower sediment supply conditions. Finally, I found that the techniques used to remove Ammophila for plover recovery have unintended consequences for the native and endemic dune plant communities, and disrupt the natural disturbance regime of shifting sand. A whole-ecosystem restoration focus would be an improvement over the target-species approach, as it would promote the return of the natural disturbance regime, which in turn, would help recover the native biological community. The findings from this dissertation research provide a robust knowledge base that can guide further investigations of biological and physical changes to the coastal dunes, can help improve the management of dune ecosystem services and the restoration of native communities, and can help anticipate the impacts of future beach grass invasions and climate change induced changes to the coast. Title: The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA Author: Zarnetske, Phoebe Lehmann, 1979- Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to study the interactions among invasive ecosystem engineers, physical features, and biological communities, because interactions among vegetation, sediment, and fluids within biophysical feedbacks create and modify distinct physical features. Further, these systems provide important ecosystem services including coastal protection afforded by their natural features. In this dissertation, I investigate the interactions and feedbacks among sand-binding beach grass species (a native, Elymus mollis (Trin.), and two non-natives, Ammophila arenaria (L.) Link and A. breviligulata Fernald), sediment supply, and dune shape along the U.S. Pacific Northwest coast. Dunes dominated by A. arenaria tend to be taller and narrower compared to the shorter, wider dunes dominated by A. breviligulata. These patterns suggest an ecological control on dune shape, and thus, coastal vulnerability to overtopping waves. I investigate the causes and consequences of these patterns with experiments, field observations, and modeling. Specifically, I investigate the relative roles of vegetation and sediment supply in shaping coastal dunes over inter-annual and multi-decadal time scales (Chapter 2), characterize a biophysical feedback between beach grass species growth habit and sediment supply (Chapter 3), uncover the mechanisms leading to beach grass coexistence and whether A. breviligulata can invade and dominate new sections of coastline (Chapter 4), and examine the non-target effects resulting from management actions that remove Ammophila for the recovery of the threatened Western Snowy plover (Charadrius alexandrinus nivosus) (Chapter 5). I found that vegetation and sediment supply play important roles in dune shape changes across inter-annual and multi-decadal time scales (Chapter 2). I determined that a biophysical feedback between the beach grass growth habits and sediment supply results in species-specific differences in sand capture ability, and thus, is a likely explanation for differences in dune shape (Chapter 3). I found that all three beach grass species can coexist across different sediment deposition rates, and that this coexistence is largely mediated by positive direct and indirect species interactions. I further determined that A. breviligulata is capable of invading and dominating the beach grass community in regions where it is currently absent (Chapter 4). Combined, these findings indicate that A. breviligulata is an inferior dune building species as compared to A. arenaria, and suggest that in combination with sediment supply gradients, these species differences ultimately lead to differences in dune shape. Potential further invasions of A. breviligulata into southern regions of the Pacific Northwest may diminish the coastal protection ability of dunes currently dominated by A. arenaria, but this effect could be moderated by the predicted near co-dominance of A. arenaria in these lower sediment supply conditions. Finally, I found that the techniques used to remove Ammophila for plover recovery have unintended consequences for the native and endemic dune plant communities, and disrupt the natural disturbance regime of shifting sand. A whole-ecosystem restoration focus would be an improvement over the target-species approach, as it would promote the return of the natural disturbance regime, which in turn, would help recover the native biological community. The findings from this dissertation research provide a robust knowledge base that can guide further investigations of biological and physical changes to the coastal dunes, can help improve the management of dune ecosystem services and the restoration of native communities, and can help anticipate the impacts of future beach grass invasions and climate change induced changes to the coast. Close

• 9. [Article] The Oligocene Fossil Caudates of Oregon: Classification, Analysis, and Insights on the Paleoecology and Conservation Biology of Pacific Newts

  Newts, abundant worldwide, have unclear pre-Pliocene evolution and phylogenetic relationships. North America has a sporadic pre-Pliocene newt record. Several undescribed fossils can address this lack ...

  Citation × Citation Citation Abstract Copy Title: The Oligocene Fossil Caudates of Oregon: Classification, Analysis, and Insights on the Paleoecology and Conservation Biology of Pacific Newts Author: Jacisin, John Year: 2014 Newts, abundant worldwide, have unclear pre-Pliocene evolution and phylogenetic relationships. North America has a sporadic pre-Pliocene newt record. Several undescribed fossils can address this lack of information. I built a character matrix of >70 morphological characters for extant newts and two fossil species, Taricha oligocenica and Taricha lindoei. Phylogenetic analyses were used to investigate the relationships of the fossil taxa within newts. The morphology of the fossil taxa was compared with extant North American newts to redescribe the fossil specimens. The past ecology and biogeography of North American fossil newts was compared with their current ecologies and distribution to better understand their evolution and dispersal and to predict possible changes for newts in the face of environmental change. Results indicate that T. oligocenica and T. lindoei are closely-related species nested within Taricha, but their relationships with extant species are unresolved; the genus itself is rooted at least 32 Ma. Title: The Oligocene Fossil Caudates of Oregon: Classification, Analysis, and Insights on the Paleoecology and Conservation Biology of Pacific Newts Author: Jacisin, John Year: 2014 Newts, abundant worldwide, have unclear pre-Pliocene evolution and phylogenetic relationships. North America has a sporadic pre-Pliocene newt record. Several undescribed fossils can address this lack of information. I built a character matrix of >70 morphological characters for extant newts and two fossil species, Taricha oligocenica and Taricha lindoei. Phylogenetic analyses were used to investigate the relationships of the fossil taxa within newts. The morphology of the fossil taxa was compared with extant North American newts to redescribe the fossil specimens. The past ecology and biogeography of North American fossil newts was compared with their current ecologies and distribution to better understand their evolution and dispersal and to predict possible changes for newts in the face of environmental change. Results indicate that T. oligocenica and T. lindoei are closely-related species nested within Taricha, but their relationships with extant species are unresolved; the genus itself is rooted at least 32 Ma. Close

• 10. [Article] Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon

  The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon Author: Al-Azzaby, Fathi Ayoub Year: 1980 The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are indicated by sedimentary structures and the abundance of pebbly lenses and coaly material. Eighteen species of megafossils collected from the formation indicate that the Spencer Formation is of the Tejon stage (late Eocene of the West Coast). Title: Stratigraphy and sedimentation of the Spencer Formation in Yamhill and Washington counties, Oregon Author: Al-Azzaby, Fathi Ayoub Year: 1980 The Spencer Formation in Yamhill and Washington Counties, Oregon, is exposed in a narrow belt 27 km long, from 1/4 to 3 km wide and with a maximum thickness of about 400 m. The formation is composed entirely of sandstone with interbedded thin layers of mudstone in the uppermost member. The sedimentary structure and paleoecology indicate a shallow marine depositional environment. The upper member of the Spencer Formation contains more quartz, plagioclase, and hornblende than does the lower member, but K-feldspar is less than that of the lower member. Shallower water conditions for the deposition of the upper member are indicated by sedimentary structures and the abundance of pebbly lenses and coaly material. Eighteen species of megafossils collected from the formation indicate that the Spencer Formation is of the Tejon stage (late Eocene of the West Coast). Close