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• 21. [Article] The predation of mudflat burrowing shrimp by native Oregon crabs Red rock crab (Cancer productus) and Dungeness crab (Cancer magister) versus an invasive crab European green crab (Carcius maenas)

  Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an ...

  Citation × Citation Citation Abstract Copy Title: The predation of mudflat burrowing shrimp by native Oregon crabs Red rock crab (Cancer productus) and Dungeness crab (Cancer magister) versus an invasive crab European green crab (Carcius maenas) Author: Trobaugh, Sean A Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an invasive species. The European green crab can be found on the mudflats competing with the native crabs, including Red rock crab (Cancer productus) and Dungeness crab (Cancer magister), for food. Possible prey includes mudflat burrowing shrimp, the Ghost shrimp, (Neotrypaea californiensis) and the Mud shrimp, (Upogebia pugettensis). Thus study examines native crab (primarily Red rock) and European green crab predation on mudflat burrowing shrimp with controlled laboratory predation experiments: putting shrimp in sediment, then adding crab after an allotted burrowing time. My hypothesis is that Red rock is able to eat more shrimp than the European green crab because of the mobility of the Red rock claws. Both invasive and native crabs preyed upon the shrimp, however, the native crabs are doing statically significant greater (p-value =.001) at getting this food source then the invasive crab. The European green crab is not out competing the Red rock and Dungeness. Title: The predation of mudflat burrowing shrimp by native Oregon crabs Red rock crab (Cancer productus) and Dungeness crab (Cancer magister) versus an invasive crab European green crab (Carcius maenas) Author: Trobaugh, Sean A Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an invasive species. The European green crab can be found on the mudflats competing with the native crabs, including Red rock crab (Cancer productus) and Dungeness crab (Cancer magister), for food. Possible prey includes mudflat burrowing shrimp, the Ghost shrimp, (Neotrypaea californiensis) and the Mud shrimp, (Upogebia pugettensis). Thus study examines native crab (primarily Red rock) and European green crab predation on mudflat burrowing shrimp with controlled laboratory predation experiments: putting shrimp in sediment, then adding crab after an allotted burrowing time. My hypothesis is that Red rock is able to eat more shrimp than the European green crab because of the mobility of the Red rock claws. Both invasive and native crabs preyed upon the shrimp, however, the native crabs are doing statically significant greater (p-value =.001) at getting this food source then the invasive crab. The European green crab is not out competing the Red rock and Dungeness. Close

• 22. [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

• 23. [Article] Economic and social impacts of restoration : a case study of the Great Basin Region

  The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations ...

  Citation × Citation Citation Abstract Copy Title: Economic and social impacts of restoration : a case study of the Great Basin Region Author: Satyal, Vijayanand H. The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations in favor of non-native species. Invasive species are known to damage not only the surrounding ecosystem but also cause economic and non-economic losses to society. This study focuses on economic and social impacts of controlling cheatgrass (Bromus tectorum L.) on the public rangelands of the Great Basin region. This research seeks to examine the economic and social impacts of adopting different restoration strategies (herbicide use, fire, grazing and re-seeding of native grasses). The economic study seeks to assess the cost-effectiveness of adopting any versus none of the restoration strategies using a linear programming multi-period optimization framework. In order to understand if restoration of cheatgrass is socially acceptable and whether the spatial context influences economic decisions, a parallel social attitudinal study examines the perceptions held by ranchers, interest groups, agency personnel and informed public with regard to restoration, the ongoing collaborative project and expected costs of undertaking restoration. The bio-economic study incorporates ranch production and ecological site specific data into representative optimization models and solves to maximize net ranch income subject to market and resource constraints. The economic study found restoration to impact the ranches financially as the degree of restoration increased. Costs of restoration were lowest under baseline conditions and increased in magnitude with use of grazing, fire, herbicide and the integrated strategy respectively. Attitudinal data indicated that the meaning of restoration and social acceptability towards restoration strategies differed within and across stakeholder groups in the Great Basin states of Oregon, Idaho, Nevada and Utah. Title: Economic and social impacts of restoration : a case study of the Great Basin Region Author: Satyal, Vijayanand H. The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations in favor of non-native species. Invasive species are known to damage not only the surrounding ecosystem but also cause economic and non-economic losses to society. This study focuses on economic and social impacts of controlling cheatgrass (Bromus tectorum L.) on the public rangelands of the Great Basin region. This research seeks to examine the economic and social impacts of adopting different restoration strategies (herbicide use, fire, grazing and re-seeding of native grasses). The economic study seeks to assess the cost-effectiveness of adopting any versus none of the restoration strategies using a linear programming multi-period optimization framework. In order to understand if restoration of cheatgrass is socially acceptable and whether the spatial context influences economic decisions, a parallel social attitudinal study examines the perceptions held by ranchers, interest groups, agency personnel and informed public with regard to restoration, the ongoing collaborative project and expected costs of undertaking restoration. The bio-economic study incorporates ranch production and ecological site specific data into representative optimization models and solves to maximize net ranch income subject to market and resource constraints. The economic study found restoration to impact the ranches financially as the degree of restoration increased. Costs of restoration were lowest under baseline conditions and increased in magnitude with use of grazing, fire, herbicide and the integrated strategy respectively. Attitudinal data indicated that the meaning of restoration and social acceptability towards restoration strategies differed within and across stakeholder groups in the Great Basin states of Oregon, Idaho, Nevada and Utah. Close

• 24. [Article] Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Public Library of Science. The published article can be found at: http://www.plosone.org/

  Citation × Citation Citation Abstract Copy Title: Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming Author: Arismendi, Ivan, Seeb, Lisa W., Seeb, James E., et al., Benavente, Javiera N. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Public Library of Science. The published article can be found at: http://www.plosone.org/ Title: Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming Author: Arismendi, Ivan, Seeb, Lisa W., Seeb, James E., et al., Benavente, Javiera N. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Public Library of Science. The published article can be found at: http://www.plosone.org/ Close

• 25. [Article] A sustainable resource development plan framework for the Neskonlith Indian Band, British Columbia

  A sustainable resource development plan framework was prepared for the Neskonlith Indian Band, who are located in the interior of British Columbia, Canada. The framework intends to address issues involving; ...

  Citation × Citation Citation Abstract Copy Title: A sustainable resource development plan framework for the Neskonlith Indian Band, British Columbia Author: Mackasey, J. Patrick A sustainable resource development plan framework was prepared for the Neskonlith Indian Band, who are located in the interior of British Columbia, Canada. The framework intends to address issues involving; integrated resource management, traditional native land management, ecosystem management, and community-based resource management. A soft systems (Wilson & Morren, 1990) methodology was used to work with the community and help assess the current management state and to begin the process of determining the desired future condition of their land base and how this can help build the community. However, the band was prepared only to work through the first two (out of seven) stages of the methodology. The study area used was 4259 ha in size, of which 1316 ha was reserve land. A good portion of this area is forested (52.4%), primarily with interior Douglas-Fir (Pseudotsuga menziesii var, glauca). The study area is also represented by 13.9% open range, 8,2% cultivated land and a large lake (11 %) . Current and past resource management activities on this area include; forestry, mining, agriculture, range, recreation, and parks. The band is interested in how the land base can be managed from an integrated resource management perspective and in learning how non-consumptive uses of the forest can be further explored. This framework attempts to answer the questions and provide the band with a working Geographic Information System database and some management alternatives to examine. A Terrasoft GIS was used, which allowed for both vector and raster processing. Data layers were compiled and assembled for a variety of resource values. These data layers were analyzed using models which produced three management alternatives. These alternatives included the following emphases: economic; ecological; and balanced. The economic alternative focused solely on resource extraction. The ecological alternative focuses on protection of the environment as the main emphasis, and large parcels of land are excluded from any resource development activities. The balanced alternative offered a balance between the first two alternatives, allowing for a reasonable level of resource management activities, while protecting important ecological components across the landscape. The trade-offs expected to be encountered with each management scenario were discussed with the community and the balanced alternative was resolved as the preferred choice. This framework is expected to be used by the band to help construct a comprehensive integrated resource management plan. Recommendations are provided with the third management alternative to assist the band with integrated resource management planning. It was concluded that although the band has much information available on resource management, they still have a great deal of work left ahead of them to become fully involved in a functional, integrated resource management program. Title: A sustainable resource development plan framework for the Neskonlith Indian Band, British Columbia Author: Mackasey, J. Patrick A sustainable resource development plan framework was prepared for the Neskonlith Indian Band, who are located in the interior of British Columbia, Canada. The framework intends to address issues involving; integrated resource management, traditional native land management, ecosystem management, and community-based resource management. A soft systems (Wilson & Morren, 1990) methodology was used to work with the community and help assess the current management state and to begin the process of determining the desired future condition of their land base and how this can help build the community. However, the band was prepared only to work through the first two (out of seven) stages of the methodology. The study area used was 4259 ha in size, of which 1316 ha was reserve land. A good portion of this area is forested (52.4%), primarily with interior Douglas-Fir (Pseudotsuga menziesii var, glauca). The study area is also represented by 13.9% open range, 8,2% cultivated land and a large lake (11 %) . Current and past resource management activities on this area include; forestry, mining, agriculture, range, recreation, and parks. The band is interested in how the land base can be managed from an integrated resource management perspective and in learning how non-consumptive uses of the forest can be further explored. This framework attempts to answer the questions and provide the band with a working Geographic Information System database and some management alternatives to examine. A Terrasoft GIS was used, which allowed for both vector and raster processing. Data layers were compiled and assembled for a variety of resource values. These data layers were analyzed using models which produced three management alternatives. These alternatives included the following emphases: economic; ecological; and balanced. The economic alternative focused solely on resource extraction. The ecological alternative focuses on protection of the environment as the main emphasis, and large parcels of land are excluded from any resource development activities. The balanced alternative offered a balance between the first two alternatives, allowing for a reasonable level of resource management activities, while protecting important ecological components across the landscape. The trade-offs expected to be encountered with each management scenario were discussed with the community and the balanced alternative was resolved as the preferred choice. This framework is expected to be used by the band to help construct a comprehensive integrated resource management plan. Recommendations are provided with the third management alternative to assist the band with integrated resource management planning. It was concluded that although the band has much information available on resource management, they still have a great deal of work left ahead of them to become fully involved in a functional, integrated resource management program. Close

• 26. [Article] Seed and establishment limitation contribute to long-term native forb declines in California grasslands

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/.

  Citation × Citation Citation Abstract Copy Title: Seed and establishment limitation contribute to long-term native forb declines in California grasslands Author: Brandt, Angela J., Seabloom, Eric W. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/. Title: Seed and establishment limitation contribute to long-term native forb declines in California grasslands Author: Brandt, Angela J., Seabloom, Eric W. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/. Close

• 27. [Article] Germination and establishment in Willamette Valley native prairie plants

  Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, ...

  Citation × Citation Citation Abstract Copy Title: Germination and establishment in Willamette Valley native prairie plants Author: Russell, Michael C. Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, and home landscapes increases so does demand for information on the basic biology of a group of species that have only been sparingly studied. Germination is one of the first major events in a plant’s life cycle and can be affected by both the physiological state of the seed and the environment the seed is in. Seeds can become dormant and may require some environmental signal for germination. I conducted a series of germination trials on a set of Willamette Valley native prairie plants to test whether cold stratification or various scarification treatments can be used to break seed dormancy. I used each species’ responses to classify the dormancy type of each species. The environmental conditions that the seed experiences also affect germination. The effect of temperature on germination was studied using a temperature gradient table. Seeds were tested to characterize species based on the temperature range at which its seeds can germinate. Germination in some species was bounded within clearly defined temperature limits, while germination in others occurred over the full range of studied temperatures. The germination data were modeled with linear regression to create standard estimates for the physiological limits of each species to allow for comparisons between the species. After seeds germinate the initial stages of establishment can have great implications on the survival of the plant. A greenhouse experiment was conducted to study the competitive interactions of six of the species. Plants were grown together in pots for 90 days and biomass collected. The mean competitive effect and competitive response of each species was calculated and the results were regressed against each species' values for several physiological traits that were available from the literature. The experiment found that species with higher relative growth rates had greater competitive effects on other species. The first two experiments measured physiological traits of several Oregon native species. The third demonstrated the utility of standardized traits in predicting ecological behavior. This trait based approach has great potential as a tool for comparing ecological similarities and differences across different ecosystems and different species pools. Title: Germination and establishment in Willamette Valley native prairie plants Author: Russell, Michael C. Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, and home landscapes increases so does demand for information on the basic biology of a group of species that have only been sparingly studied. Germination is one of the first major events in a plant’s life cycle and can be affected by both the physiological state of the seed and the environment the seed is in. Seeds can become dormant and may require some environmental signal for germination. I conducted a series of germination trials on a set of Willamette Valley native prairie plants to test whether cold stratification or various scarification treatments can be used to break seed dormancy. I used each species’ responses to classify the dormancy type of each species. The environmental conditions that the seed experiences also affect germination. The effect of temperature on germination was studied using a temperature gradient table. Seeds were tested to characterize species based on the temperature range at which its seeds can germinate. Germination in some species was bounded within clearly defined temperature limits, while germination in others occurred over the full range of studied temperatures. The germination data were modeled with linear regression to create standard estimates for the physiological limits of each species to allow for comparisons between the species. After seeds germinate the initial stages of establishment can have great implications on the survival of the plant. A greenhouse experiment was conducted to study the competitive interactions of six of the species. Plants were grown together in pots for 90 days and biomass collected. The mean competitive effect and competitive response of each species was calculated and the results were regressed against each species' values for several physiological traits that were available from the literature. The experiment found that species with higher relative growth rates had greater competitive effects on other species. The first two experiments measured physiological traits of several Oregon native species. The third demonstrated the utility of standardized traits in predicting ecological behavior. This trait based approach has great potential as a tool for comparing ecological similarities and differences across different ecosystems and different species pools. Close

• 28. [Article] Biological Erosion of Marine Habitats and Structures by Burrowing Crustaceans

  Marine bioeroders, borers, and burrowers can have drastic effects to marine habitats and facilities. By physically altering the structure of marine habitats, these organisms may elicit ecosystem-level ...

  Citation × Citation Citation Abstract Copy Title: Biological Erosion of Marine Habitats and Structures by Burrowing Crustaceans Author: Davidson, Timothy Mathias Year: 2011 Marine bioeroders, borers, and burrowers can have drastic effects to marine habitats and facilities. By physically altering the structure of marine habitats, these organisms may elicit ecosystem-level effects that cascade through the community. While borer damage is typically restricted to a few substratum types, burrowing isopods in the genus Sphaeroma attack a diversity of substrata in tropical and temperate systems. My dissertation examined how boring sphaeromatid isopods affect coastal habitats (saltmarshes, mangroves) and other estuarine substrata as well as marine structures. I used a combination of lab and mensurative field experiments to quantify the effects of boring by isopods and examine how select factors affect the colonization, hence burrowing damage by isopods. I explored these questions primarily using the temperate boring sphaeromatid, Sphaeroma quoianum, as a model organism. My initial lab experiments quantified the per capita erosion rates of S. quoianum in four commonly attacked estuarine substrata. I found marsh banks and Styrofoam substrata were the most affected per capita. I supplemented this lab experiment with a year-long mensurative field experiment examining how erosion rates differ between marshes infested and uninfested by boring isopods. Marshes infested with isopods eroded 300% faster than uninfested marshes. I further examined the boring effects on Styrofoam floats. I compiled surveys and observations and conducted a short experiment to describe how isopods affect Styrofoam floats used in floating docks. I observed dense colonies of isopods attacking floats and expelling millions of plastic particles in the ocean. The boring effects to simulated Styrofoam floats were also affected by seawater temperature. Burrowing effects in Styrofoam floats exhibited a curvilinear relationship with temperature and peaked around 18°C. These results suggest a 1-2°C increase in water temperature could increase boring effects 5-17% of populations of isopods in Oregon and California bays. To examine the small-scale factors that mediate colonization and boring, I conducted a series of binary choice experiments. I found the presence of conspecifics, biofilm, and shade were important factors influencing colonization. These small scale factors likely explain why isopod attack is focused in some substrata. Finally, to examine the boring effects of tropical isopods in mangroves, I examined the associations between burrowing by S. terebrans and mangrove performance and fecundity. I found negative relationships between boring effects and performance and fecundity in two mangrove species in a restored mangrove stand in Taiwan. Together, these studies elucidate the effects of bioerosive isopods on saltmarshes, mangroves, and marine structures. However, the similar mechanisms involved in bioerosion in other boring species suggest that these results can be used to infer similar effects of other borers. In addition, since many species of sphaeromatid isopods have been introduced, this research shows how the effects of a non-native bioeroder can damage marine facilities and degrade and alter marine habitats. Through biological erosion and thus changing the physical structure of a marine habitat these non-native species can have ecosystem-level effects that cascade throughout the local community. Title: Biological Erosion of Marine Habitats and Structures by Burrowing Crustaceans Author: Davidson, Timothy Mathias Year: 2011 Marine bioeroders, borers, and burrowers can have drastic effects to marine habitats and facilities. By physically altering the structure of marine habitats, these organisms may elicit ecosystem-level effects that cascade through the community. While borer damage is typically restricted to a few substratum types, burrowing isopods in the genus Sphaeroma attack a diversity of substrata in tropical and temperate systems. My dissertation examined how boring sphaeromatid isopods affect coastal habitats (saltmarshes, mangroves) and other estuarine substrata as well as marine structures. I used a combination of lab and mensurative field experiments to quantify the effects of boring by isopods and examine how select factors affect the colonization, hence burrowing damage by isopods. I explored these questions primarily using the temperate boring sphaeromatid, Sphaeroma quoianum, as a model organism. My initial lab experiments quantified the per capita erosion rates of S. quoianum in four commonly attacked estuarine substrata. I found marsh banks and Styrofoam substrata were the most affected per capita. I supplemented this lab experiment with a year-long mensurative field experiment examining how erosion rates differ between marshes infested and uninfested by boring isopods. Marshes infested with isopods eroded 300% faster than uninfested marshes. I further examined the boring effects on Styrofoam floats. I compiled surveys and observations and conducted a short experiment to describe how isopods affect Styrofoam floats used in floating docks. I observed dense colonies of isopods attacking floats and expelling millions of plastic particles in the ocean. The boring effects to simulated Styrofoam floats were also affected by seawater temperature. Burrowing effects in Styrofoam floats exhibited a curvilinear relationship with temperature and peaked around 18°C. These results suggest a 1-2°C increase in water temperature could increase boring effects 5-17% of populations of isopods in Oregon and California bays. To examine the small-scale factors that mediate colonization and boring, I conducted a series of binary choice experiments. I found the presence of conspecifics, biofilm, and shade were important factors influencing colonization. These small scale factors likely explain why isopod attack is focused in some substrata. Finally, to examine the boring effects of tropical isopods in mangroves, I examined the associations between burrowing by S. terebrans and mangrove performance and fecundity. I found negative relationships between boring effects and performance and fecundity in two mangrove species in a restored mangrove stand in Taiwan. Together, these studies elucidate the effects of bioerosive isopods on saltmarshes, mangroves, and marine structures. However, the similar mechanisms involved in bioerosion in other boring species suggest that these results can be used to infer similar effects of other borers. In addition, since many species of sphaeromatid isopods have been introduced, this research shows how the effects of a non-native bioeroder can damage marine facilities and degrade and alter marine habitats. Through biological erosion and thus changing the physical structure of a marine habitat these non-native species can have ecosystem-level effects that cascade throughout the local community. Close

• 29. [Image] Recovery plan for the native fishes of the Warner Basin and Alkali Subbasin : Warner sucker (threatened) Catostomus warnerensis, Hutton tui chub (threatened) Gila bicolor ssp. Foskett speckled dace (threatened) Rhinichthys osculus ssp

  	"April 1998"--P. [4] of cover; Includes bibliographical references (p. 57-66)
  	Citation × Citation Citation Abstract Copy Title: Recovery plan for the native fishes of the Warner Basin and Alkali Subbasin : Warner sucker (threatened) Catostomus warnerensis, Hutton tui chub (threatened) Gila bicolor ssp. Foskett speckled dace (threatened) Rhinichthys osculus ssp Author: U.S. Fish and Wildlife Service. Oregon State Office Year: 1998, 2004 "April 1998"--P. [4] of cover; Includes bibliographical references (p. 57-66) Title: Recovery plan for the native fishes of the Warner Basin and Alkali Subbasin : Warner sucker (threatened) Catostomus warnerensis, Hutton tui chub (threatened) Gila bicolor ssp. Foskett speckled dace (threatened) Rhinichthys osculus ssp Author: U.S. Fish and Wildlife Service. Oregon State Office Year: 1998, 2004 "April 1998"--P. [4] of cover; Includes bibliographical references (p. 57-66) Close

• 30. [Image] Integrated scientific assessment for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins

  	Abstract Quigley, Thomas M.; Haynes, Richard W.; Graham, Russell T., tech. eds. 1996. Integrated scientific assessment for ecosystem management in the interior Columbia basin and portions of the Klamath ...
  	Citation × Citation Citation Abstract Copy Title: Integrated scientific assessment for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins Year: 1996, 2005, 2000 Abstract Quigley, Thomas M.; Haynes, Richard W.; Graham, Russell T., tech. eds. 1996. Integrated scientific assessment for ecosystem management in the interior Columbia basin and portions of the Klamath and Great Basins. Gen. Tech. Rep. PNW-GTR-382. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 303 p. (Quigley, Thomas M., tech. ed. The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment.) The Integrated Scientific Assessment for Ecosystem Management for the Interior Columbia Basin links landscape, aquatic, terrestrial, social, and economic characterizations to describe biophysical and social systems. Integration was achieved through a framework built around six goals for ecosystem management and three different views of the future. These goals are: maintain evolutionary and ecological processes; manage for multiple ecological domains and evolutionary timeframes; maintain viable populations of native and desired non-native species; encourage social and economic resiliency; manage for places with definable values; and, manage to maintain a variety of ecosystem goods, services, and conditions that society wants. Ratings of relative ecological integrity and socioeconomic resiliency were used to make broad statements about ecosystem conditions in the Basin. Currently in the Basin high integrity and resiliency are found on 16 and 20 percent of the area, respectively. Low integrity and resiliency are found on 60 and 68 percent of the area. Different approaches to management can alter the risks to the assets of people living in the Basin and to the ecosystem itself. Continuation of current management leads to increasing risks while management approaches focusing on reserves or restoration result in trends that mostly stabilize or reduce risks. Even where ecological integrity is projected to improve with the application of active management, population increases and the pressures of expanding demands on resources may cause increasing trends in risk. Keywords: Ecosystem assessment, management and goals; ecological integrity; socio-economic resiliency; risk management Title: Integrated scientific assessment for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins Year: 1996, 2005, 2000 Abstract Quigley, Thomas M.; Haynes, Richard W.; Graham, Russell T., tech. eds. 1996. Integrated scientific assessment for ecosystem management in the interior Columbia basin and portions of the Klamath and Great Basins. Gen. Tech. Rep. PNW-GTR-382. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 303 p. (Quigley, Thomas M., tech. ed. The Interior Columbia Basin Ecosystem Management Project: Scientific Assessment.) The Integrated Scientific Assessment for Ecosystem Management for the Interior Columbia Basin links landscape, aquatic, terrestrial, social, and economic characterizations to describe biophysical and social systems. Integration was achieved through a framework built around six goals for ecosystem management and three different views of the future. These goals are: maintain evolutionary and ecological processes; manage for multiple ecological domains and evolutionary timeframes; maintain viable populations of native and desired non-native species; encourage social and economic resiliency; manage for places with definable values; and, manage to maintain a variety of ecosystem goods, services, and conditions that society wants. Ratings of relative ecological integrity and socioeconomic resiliency were used to make broad statements about ecosystem conditions in the Basin. Currently in the Basin high integrity and resiliency are found on 16 and 20 percent of the area, respectively. Low integrity and resiliency are found on 60 and 68 percent of the area. Different approaches to management can alter the risks to the assets of people living in the Basin and to the ecosystem itself. Continuation of current management leads to increasing risks while management approaches focusing on reserves or restoration result in trends that mostly stabilize or reduce risks. Even where ecological integrity is projected to improve with the application of active management, population increases and the pressures of expanding demands on resources may cause increasing trends in risk. Keywords: Ecosystem assessment, management and goals; ecological integrity; socio-economic resiliency; risk management Close

• 31. [Image] A framework for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins

  	Haynes, Richard W.; Graham, Russell T.; Quigley, Thomas M., tech. eds. 1996. A framework for ecosystem management in the Interior Columbia Basin including portions of the Klamath and Great Basins. Gen. ...
  	Citation × Citation Citation Abstract Copy Title: A framework for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins Year: 1996, 2005 Haynes, Richard W.; Graham, Russell T.; Quigley, Thomas M., tech. eds. 1996. A framework for ecosystem management in the Interior Columbia Basin including portions of the Klamath and Great Basins. Gen. Tech. Rep. PNW-GTR-374. Portland, OR; U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 66 p. A framework for ecosystem management is proposed. This framework assumes the purpose of ecosystem management is to maintain the integrity of ecosystems over time and space. It is based on four ecosystem principles: ecosystems are dynamic, can be viewed as hierarchies with temporal and spatial dimensions, have limits, and are relatively unpredictable. This approach recognizes that people are part of ecosystems and that stewardship must be able to resolve tough challenges including how to meet multiple demands with finite resources. The framework describes a general planning model for ecosystem management that has four iterative steps: monitoring, assessment, decision-making, and implementation. Since ecosystems cross jurisdictional lines, the implementation of the framework depends on partnerships among land managers, the scientific community, and stakeholders. It proposes that decision-making be based on information provided by the best available science and the most appropriate technologies for land management. Keywords: Ecosystem assessment, ecosystem principles, ecosystem management, planning models, management goals, risk analysis. Title: A framework for ecosystem management in the interior Columbia Basin and portions of the Klamath and Great Basins Year: 1996, 2005 Haynes, Richard W.; Graham, Russell T.; Quigley, Thomas M., tech. eds. 1996. A framework for ecosystem management in the Interior Columbia Basin including portions of the Klamath and Great Basins. Gen. Tech. Rep. PNW-GTR-374. Portland, OR; U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 66 p. A framework for ecosystem management is proposed. This framework assumes the purpose of ecosystem management is to maintain the integrity of ecosystems over time and space. It is based on four ecosystem principles: ecosystems are dynamic, can be viewed as hierarchies with temporal and spatial dimensions, have limits, and are relatively unpredictable. This approach recognizes that people are part of ecosystems and that stewardship must be able to resolve tough challenges including how to meet multiple demands with finite resources. The framework describes a general planning model for ecosystem management that has four iterative steps: monitoring, assessment, decision-making, and implementation. Since ecosystems cross jurisdictional lines, the implementation of the framework depends on partnerships among land managers, the scientific community, and stakeholders. It proposes that decision-making be based on information provided by the best available science and the most appropriate technologies for land management. Keywords: Ecosystem assessment, ecosystem principles, ecosystem management, planning models, management goals, risk analysis. Close

• 32. [Image] The Oregon conservation strategy

  	v, 419 p.; col.ill.; col.maps; "February 2006"; Foreword by Marla Rae, Chair, Oregon Fish and Wildlife Commission
  	Citation × Citation Citation Abstract Copy Title: The Oregon conservation strategy Year: 2006 v, 419 p.; col.ill.; col.maps; "February 2006"; Foreword by Marla Rae, Chair, Oregon Fish and Wildlife Commission Title: The Oregon conservation strategy Year: 2006 v, 419 p.; col.ill.; col.maps; "February 2006"; Foreword by Marla Rae, Chair, Oregon Fish and Wildlife Commission Close

• 33. [Image] Klamath Falls Resource Area resource management plan and environmental impact statement : final : Volume 2

  	Proposed resource management plan/final environmental impact statement for the Klamath Falls Resource Area
  	Citation × Citation Citation Abstract Copy Title: Klamath Falls Resource Area resource management plan and environmental impact statement : final : Volume 2 Author: United States. Bureau of Land Management. Klamath Falls Resource Area Office Year: 1994, 2005, 2004 Proposed resource management plan/final environmental impact statement for the Klamath Falls Resource Area Title: Klamath Falls Resource Area resource management plan and environmental impact statement : final : Volume 2 Author: United States. Bureau of Land Management. Klamath Falls Resource Area Office Year: 1994, 2005, 2004 Proposed resource management plan/final environmental impact statement for the Klamath Falls Resource Area Close

• 34. [Article] Habitat relationships of native and non-native fishes of the Willamette River, Oregon

  The Willamette River flows north between the Cascade Mountains and Coast Range of western Oregon within a 29,728-km² basin. The fish community in the geologically young basin consists of 36 native species, ...

  Citation × Citation Citation Abstract Copy Title: Habitat relationships of native and non-native fishes of the Willamette River, Oregon Author: Williams, Joshua E. (Joshua Everett) The Willamette River flows north between the Cascade Mountains and Coast Range of western Oregon within a 29,728-km² basin. The fish community in the geologically young basin consists of 36 native species, but introductions of non-native fishes have added 33 additional species for a total of 69 fish species. During the summers of 2011-2013, fish distributions were sampled from the confluence of the McKenzie River downstream to the confluence of the Columbia River to assess: (1) fish community composition, (2) differences in community composition between mainstem river and slough habitats, and (3) relationships between native and non-native fish species and physical habitat characteristics. In addition, a 182-ha seasonally inundated floodplain habitat along the middle Willamette River was sampled during winter 2011 through spring 2012 to assess: (1) fish community composition, (2) spawning and rearing, and (3) timing of use and movement by fish species. Throughout the three years of longitudinal sampling, 36,586 fish were collected comprising 41 species, 22 native and 19 non-native. Overall, native fish represented 93% of the total fish sampled. Higher numbers of fish were collected in the upper river, and higher proportions of those fish were native species. Though non-native fish were more common in slough habitats than mainstem sties, the majority of fish collected in both habitat types were native. The strongest environmental predictors of fish community were quantitative measures of longitudinal distance, velocity, depth, percent macrophyte cover and percent embeddedness. Habitat type (slough versus mainstem) was also a significant predictor. Native fish species exhibited greater variability in habitat relationships than non-native fishes, though several native species were strongly associated with specific environmental attributes. Non-native species were more associated with slough habitats and sites with high amount of macrophyte growth and embedded substrates. Overall, 25 species had a high fidelity to mainstem or slough habitats. Equal numbers of native species showed a fidelity to either mainstem or slough sites, but non-native species were significantly related only to slough habitats. In the seasonally inundated floodplain habitat, an estimated 43,000 fish were collected comprising 23 species; 12 native and 11 non-native. Of these 98.1% were native. The most common native species were threespine stickleback Gasterosteus aculeatus and peamouth Mylocheilus caurinus while the most common non-native species were bluegill Lepomis macrochirus and western mosquitofish Gambusia affinus. Several species used the inundated floodplain for spawning and rearing, particularly threespine stickleback, peamouth and western mosquitofish. With the exception of young-of-year threespine stickleback, native species were collected mostly in the beginning and middle of the sampling period while non-native species were collected in the latter portion of the sampling. The Willamette River Basin has a long history of environmental modification. Understanding relationships of a broad range of species to their environment and to each other provides a technical foundation for ecosystem based management by state and federal agencies, local municipalities, and private landowners. The need for ecosystem based management is vital for future conservation and recovery of large river floodplain ecosystems. Title: Habitat relationships of native and non-native fishes of the Willamette River, Oregon Author: Williams, Joshua E. (Joshua Everett) The Willamette River flows north between the Cascade Mountains and Coast Range of western Oregon within a 29,728-km² basin. The fish community in the geologically young basin consists of 36 native species, but introductions of non-native fishes have added 33 additional species for a total of 69 fish species. During the summers of 2011-2013, fish distributions were sampled from the confluence of the McKenzie River downstream to the confluence of the Columbia River to assess: (1) fish community composition, (2) differences in community composition between mainstem river and slough habitats, and (3) relationships between native and non-native fish species and physical habitat characteristics. In addition, a 182-ha seasonally inundated floodplain habitat along the middle Willamette River was sampled during winter 2011 through spring 2012 to assess: (1) fish community composition, (2) spawning and rearing, and (3) timing of use and movement by fish species. Throughout the three years of longitudinal sampling, 36,586 fish were collected comprising 41 species, 22 native and 19 non-native. Overall, native fish represented 93% of the total fish sampled. Higher numbers of fish were collected in the upper river, and higher proportions of those fish were native species. Though non-native fish were more common in slough habitats than mainstem sties, the majority of fish collected in both habitat types were native. The strongest environmental predictors of fish community were quantitative measures of longitudinal distance, velocity, depth, percent macrophyte cover and percent embeddedness. Habitat type (slough versus mainstem) was also a significant predictor. Native fish species exhibited greater variability in habitat relationships than non-native fishes, though several native species were strongly associated with specific environmental attributes. Non-native species were more associated with slough habitats and sites with high amount of macrophyte growth and embedded substrates. Overall, 25 species had a high fidelity to mainstem or slough habitats. Equal numbers of native species showed a fidelity to either mainstem or slough sites, but non-native species were significantly related only to slough habitats. In the seasonally inundated floodplain habitat, an estimated 43,000 fish were collected comprising 23 species; 12 native and 11 non-native. Of these 98.1% were native. The most common native species were threespine stickleback Gasterosteus aculeatus and peamouth Mylocheilus caurinus while the most common non-native species were bluegill Lepomis macrochirus and western mosquitofish Gambusia affinus. Several species used the inundated floodplain for spawning and rearing, particularly threespine stickleback, peamouth and western mosquitofish. With the exception of young-of-year threespine stickleback, native species were collected mostly in the beginning and middle of the sampling period while non-native species were collected in the latter portion of the sampling. The Willamette River Basin has a long history of environmental modification. Understanding relationships of a broad range of species to their environment and to each other provides a technical foundation for ecosystem based management by state and federal agencies, local municipalities, and private landowners. The need for ecosystem based management is vital for future conservation and recovery of large river floodplain ecosystems. Close

• 35. [Article] Aquatic Ecosystems Symposium

  Abstract -- Sustainability and changing physical landscapes; sustainability of western riparian ecosystems, watersheds: nutrients and productivity, sustaining of western aquatic food webs, western native ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Ecosystems Symposium Abstract -- Sustainability and changing physical landscapes; sustainability of western riparian ecosystems, watersheds: nutrients and productivity, sustaining of western aquatic food webs, western native fish resources. Toward a robust water policy for western USA. A synthesis of the science. Title: Aquatic Ecosystems Symposium Abstract -- Sustainability and changing physical landscapes; sustainability of western riparian ecosystems, watersheds: nutrients and productivity, sustaining of western aquatic food webs, western native fish resources. Toward a robust water policy for western USA. A synthesis of the science. Close

• 36. [Article] The effects of native plants on non-native plant abundance in a restoration setting : differences among native species and the predictive ability of species traits

  Reducing the cover of non-native species is one of the challenges of ecosystem restoration. The goal of this study is to identify native species traits that will increase native species cover and reduce ...

  Citation × Citation Citation Abstract Copy Title: The effects of native plants on non-native plant abundance in a restoration setting : differences among native species and the predictive ability of species traits Author: Goodridge, Jennifer M. Reducing the cover of non-native species is one of the challenges of ecosystem restoration. The goal of this study is to identify native species traits that will increase native species cover and reduce non-native species cover in the first growing season at upland and wetland prairie restoration sites. Native and non-native prairie species were planted in the fall and harvested the following summer at both an upland and a wetland site. Native species traits, such as plant weight, leaf area, relative growth rate, leaf area ratio, leaf weight ratio, net assimilation rate, and specific leaf area were measured under laboratory conditions for 7- and 21-day old seedlings. Germination rate (laboratory) and phenology (field) were also measured. At the upland site, species with a large 7-day plant weight and a high germination rate also had high native cover in the field (P<0.00l, R²=0.83). At the wetland site, high 21-day leaf area, low 21-day leaf weight ratio, and high net assimilation rate predicted increased native cover in the field (P<0.00l, R²=0.87). An abundance of natives, as measured by native cover, native biomass, and number of individuals, likely results in fewer resources (light, nutrients, and water) available for the non-native species growth resulting in a reduction in the non-native cover. Intrinsic traits of native species also predicted the field performance of non-native species, although the amount of variation explained was lower than the amount of variation explained in the models that predicted native cover. In the upland site, native species with high leaf weight ratio (21-day) tended to have lower non-native cover in their field plots (P=0.087, R²=0.23). In the wetland site, the native species traits that predict non-native cover were low 21-day leaf area and high 21-day leaf weight ratio (P<0.00l, R²=0.46). These traits were similar to those that predicted native species cover at the wetland site. This study demonstrates the ability of species traits to predict field performance. Predictive models were generated using native species traits to select species for restoration that will increase native cover and decrease non-native cover in the first growing season. Traits can be measured for species not included in this study and the models generated can be used to predict the field performance of species at similar sites. Title: The effects of native plants on non-native plant abundance in a restoration setting : differences among native species and the predictive ability of species traits Author: Goodridge, Jennifer M. Reducing the cover of non-native species is one of the challenges of ecosystem restoration. The goal of this study is to identify native species traits that will increase native species cover and reduce non-native species cover in the first growing season at upland and wetland prairie restoration sites. Native and non-native prairie species were planted in the fall and harvested the following summer at both an upland and a wetland site. Native species traits, such as plant weight, leaf area, relative growth rate, leaf area ratio, leaf weight ratio, net assimilation rate, and specific leaf area were measured under laboratory conditions for 7- and 21-day old seedlings. Germination rate (laboratory) and phenology (field) were also measured. At the upland site, species with a large 7-day plant weight and a high germination rate also had high native cover in the field (P<0.00l, R²=0.83). At the wetland site, high 21-day leaf area, low 21-day leaf weight ratio, and high net assimilation rate predicted increased native cover in the field (P<0.00l, R²=0.87). An abundance of natives, as measured by native cover, native biomass, and number of individuals, likely results in fewer resources (light, nutrients, and water) available for the non-native species growth resulting in a reduction in the non-native cover. Intrinsic traits of native species also predicted the field performance of non-native species, although the amount of variation explained was lower than the amount of variation explained in the models that predicted native cover. In the upland site, native species with high leaf weight ratio (21-day) tended to have lower non-native cover in their field plots (P=0.087, R²=0.23). In the wetland site, the native species traits that predict non-native cover were low 21-day leaf area and high 21-day leaf weight ratio (P<0.00l, R²=0.46). These traits were similar to those that predicted native species cover at the wetland site. This study demonstrates the ability of species traits to predict field performance. Predictive models were generated using native species traits to select species for restoration that will increase native cover and decrease non-native cover in the first growing season. Traits can be measured for species not included in this study and the models generated can be used to predict the field performance of species at similar sites. Close

• 37. [Article] Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems

  The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. ...

  Citation × Citation Citation Abstract Copy Title: Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems Author: Bergh, Jennifer E. The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity. To sustain robust populations, bees need nesting habitat and quality forage resources. This thesis describes two studies related to the relationship between bee diversity and landscape floral resource availability in two Willamette Valley ecosystems: wet prairies and blueberry agroecosystems. The wetlands are florally diverse, heterogeneous, and temporally patchy in spring and summer, whereas blueberries are florally abundant during spring crop bloom with potentially fewer floral resources after berry set; the intention of these studies was to determine if the floral resources in each ecosystem were adequate to support robust native bee communities. For each site type, the bee fauna and associated melittophilous floral resources are described and characterized. In the studies, it was determined that bee diversity, and specifically bee abundance, was positively correlated with floral resources. This thesis presents the results of community analyses, floral resources that were identified as important forage sources, and a discussion of the relationship between landscape phenology and bee population dynamics in each ecosystem type. Implications and recommendations for landscape management to conserve and potentially enhance local native bee communities are discussed. Title: Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems Author: Bergh, Jennifer E. The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity. To sustain robust populations, bees need nesting habitat and quality forage resources. This thesis describes two studies related to the relationship between bee diversity and landscape floral resource availability in two Willamette Valley ecosystems: wet prairies and blueberry agroecosystems. The wetlands are florally diverse, heterogeneous, and temporally patchy in spring and summer, whereas blueberries are florally abundant during spring crop bloom with potentially fewer floral resources after berry set; the intention of these studies was to determine if the floral resources in each ecosystem were adequate to support robust native bee communities. For each site type, the bee fauna and associated melittophilous floral resources are described and characterized. In the studies, it was determined that bee diversity, and specifically bee abundance, was positively correlated with floral resources. This thesis presents the results of community analyses, floral resources that were identified as important forage sources, and a discussion of the relationship between landscape phenology and bee population dynamics in each ecosystem type. Implications and recommendations for landscape management to conserve and potentially enhance local native bee communities are discussed. Close

• 38. [Article] Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California

  Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody ...

  Citation × Citation Citation Abstract Copy Title: Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California Author: Ellsworth, Lisa M. Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused on a persistent belief that fire in sagebrush systems results in a loss of native flora and a trend toward dominance by exotic annuals. Fire was historically the dominant disturbance throughout the sagebrush steppe and the plant species that comprised these communities possess a variety of adaptations facilitating survival to the fire regime. In order to restore ecosystems, land managers will need to reintroduce natural ecosystem processes, including natural disturbance processes. To describe the response of these plant communities to fire, I examined the plant community response, seedbank response, and reproductive and density responses of three native bunchgrasses (Pseudoroegneria spicata, Achnatherum therberianum, and Elymus elymoides) as well as one native forb (Calochortus macrocarpus) following spring and fall prescribed fires at Lava Beds National Monument. Fires were applied to three Artemisia tridentata ssp. vaseyana (Mountain Big Sagebrush) plant communities with different land use and fire histories. These communities were different in composition ranging from a dominance of exotic annuals to dominance by native grasses, shrubs, and trees. Little is known about how prescribed fire affects the soil seed bank in sagebrush-dominated ecosystems. To address this, we quantified the emergence of Bromus tectorum (cheatgrass) seedlings as well as emergence of seedlings of functional groups (native forbs, bunchgrasses, and shrubs) in a seedbank germination study. At the invasive dominated site (Gillems Camp), we found 91% fewer B. tectorum seedlings germinated in spring burned sites than in controls immediately following spring prescribed burns. However, soils collected one-year following fire had 40% more B. tectorum germinants (8017 germinants/m [superscript 2]) than unburned controls (5132 germinants/m [superscript 2]). Following fall burns at this site there was a similar response, with a 56% immediate reduction in B. tectorum (as compared to unburned control) and a 59% increase in B. tectorum and 58% increase in exotic forb germinants one year following fires. There was an increase in native forb germination following spring burns (94%) and fall burns (45%) at a site dominated by native plants (Fleener Chimneys). Native bunchgrass seed germination declined following spring fire in sites dominated by sagebrush and native understory vegetation (79%), and in sites where Juniperus occidentalis (western juniper) and other woody species dominated (Merrill Caves) (71%). In invasive-dominated sites (Gillems Camp), there was a decrease in B. tectorum cover following both spring (81% decrease) and fall fires (82% decrease), and little native vegetation composition change. Shrub cover, made up predominantly of Chrysothamnus nauseosus, decreased following spring (95% decrease) and fall (93% decrease) fires. At the sagebrush, native understory site (Fleener Chimneys), there was a reduction in native bunchgrass cover (64% decrease), and an increase in native forbs (168% increase) following spring burns, with no changes following fall fires. At the juniper- woody dominated site (Merrill Caves), fire treatments resulted in a decrease in woody plant cover, with no immediate postfire differences seen in the herbaceous plant community. Density of bunchgrass species (Pseudoroegneria spicata, Achnatherum therberianum, Elymus elymoides) did not change following either spring or fall prescribed fire treatments. Fire enhanced flowering was not seen in C. macrocarpus following spring or fall burns at the native or juniper dominated sites. There was increased reproductive effort in native bunchgrass species following fires in all communities studied. Following spring fires at invasive dominated sites, there was a 245% increase in reproductive culms of P. spicata. Following fall fires in native dominated sites, we saw a 974% increase in reproductive culms of P. spicata and a 184% increase in reproductive culms of A. therberianum. Following fall fires at juniper-dominated sites, we saw in an increase in reproductive culms of P. spicata (678% increase), A. thurberianum (356% increase), and Elymus elymoides (209% increase). These results suggest that implementing prescribed fire in order to restore the natural disturbance regime in these fire-adapted ecosystems is beneficial to restoration and preservation of the native biota. Title: Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California Author: Ellsworth, Lisa M. Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused on a persistent belief that fire in sagebrush systems results in a loss of native flora and a trend toward dominance by exotic annuals. Fire was historically the dominant disturbance throughout the sagebrush steppe and the plant species that comprised these communities possess a variety of adaptations facilitating survival to the fire regime. In order to restore ecosystems, land managers will need to reintroduce natural ecosystem processes, including natural disturbance processes. To describe the response of these plant communities to fire, I examined the plant community response, seedbank response, and reproductive and density responses of three native bunchgrasses (Pseudoroegneria spicata, Achnatherum therberianum, and Elymus elymoides) as well as one native forb (Calochortus macrocarpus) following spring and fall prescribed fires at Lava Beds National Monument. Fires were applied to three Artemisia tridentata ssp. vaseyana (Mountain Big Sagebrush) plant communities with different land use and fire histories. These communities were different in composition ranging from a dominance of exotic annuals to dominance by native grasses, shrubs, and trees. Little is known about how prescribed fire affects the soil seed bank in sagebrush-dominated ecosystems. To address this, we quantified the emergence of Bromus tectorum (cheatgrass) seedlings as well as emergence of seedlings of functional groups (native forbs, bunchgrasses, and shrubs) in a seedbank germination study. At the invasive dominated site (Gillems Camp), we found 91% fewer B. tectorum seedlings germinated in spring burned sites than in controls immediately following spring prescribed burns. However, soils collected one-year following fire had 40% more B. tectorum germinants (8017 germinants/m [superscript 2]) than unburned controls (5132 germinants/m [superscript 2]). Following fall burns at this site there was a similar response, with a 56% immediate reduction in B. tectorum (as compared to unburned control) and a 59% increase in B. tectorum and 58% increase in exotic forb germinants one year following fires. There was an increase in native forb germination following spring burns (94%) and fall burns (45%) at a site dominated by native plants (Fleener Chimneys). Native bunchgrass seed germination declined following spring fire in sites dominated by sagebrush and native understory vegetation (79%), and in sites where Juniperus occidentalis (western juniper) and other woody species dominated (Merrill Caves) (71%). In invasive-dominated sites (Gillems Camp), there was a decrease in B. tectorum cover following both spring (81% decrease) and fall fires (82% decrease), and little native vegetation composition change. Shrub cover, made up predominantly of Chrysothamnus nauseosus, decreased following spring (95% decrease) and fall (93% decrease) fires. At the sagebrush, native understory site (Fleener Chimneys), there was a reduction in native bunchgrass cover (64% decrease), and an increase in native forbs (168% increase) following spring burns, with no changes following fall fires. At the juniper- woody dominated site (Merrill Caves), fire treatments resulted in a decrease in woody plant cover, with no immediate postfire differences seen in the herbaceous plant community. Density of bunchgrass species (Pseudoroegneria spicata, Achnatherum therberianum, Elymus elymoides) did not change following either spring or fall prescribed fire treatments. Fire enhanced flowering was not seen in C. macrocarpus following spring or fall burns at the native or juniper dominated sites. There was increased reproductive effort in native bunchgrass species following fires in all communities studied. Following spring fires at invasive dominated sites, there was a 245% increase in reproductive culms of P. spicata. Following fall fires in native dominated sites, we saw a 974% increase in reproductive culms of P. spicata and a 184% increase in reproductive culms of A. therberianum. Following fall fires at juniper-dominated sites, we saw in an increase in reproductive culms of P. spicata (678% increase), A. thurberianum (356% increase), and Elymus elymoides (209% increase). These results suggest that implementing prescribed fire in order to restore the natural disturbance regime in these fire-adapted ecosystems is beneficial to restoration and preservation of the native biota. Close

• 39. [Article] Drivers of plant community dynamics in sagebrush steppe ecosystems : cattle grazing, heat and water stress

  Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems' resilience ...

  Citation × Citation Citation Abstract Copy Title: Drivers of plant community dynamics in sagebrush steppe ecosystems : cattle grazing, heat and water stress Author: Reisner, Michael D. Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems' resilience to disturbance and invasion by Bromus tectorum (cheatgrass). The role of the foundational shrub Artemisia as a driver of herbaceous community structure and dynamics during this degradation process is poorly understood. Many of the individual factors driving B. tectorum invasions are well documented. However a predictive understanding of the relative importance of complex, interacting factors in the causal network of simultaneously occurring processes determining invasibility has proven elusive. I examined these issues at the landscape level across 75 sites capturing a range of soil and landscape properties and cattle grazing levels similar to those found across the Great Basin. Cumulative cattle herbivory stress levels were a predominant component of both the overlapping heat and water stress gradients driving the structure of Artemisia interactions with herbaceous species. Consistent with the stress gradient hypothesis, Artemisia facilitation of herbaceous species was most frequent and strongest at the highest stress levels, and competition was most frequent and strongest at the lowest stress levels. The two species with the highest competitive response abilities, Elymus elymoides and Poa secunda, showed the strongest facilitation at the upper limits of their stress tolerances. The structure of Artemisia interactions with the invasive B. tectorum was strikingly different than those with native bunchgrasses. Artemisia interactions with native bunchgrasses shifted from competition to facilitation with increasing heat, water, and herbivory stress, but its interactions remained competitive with B. tectorum along the entire stress gradient. Shifts in the structure of interactions between Artemisia and native bunchgrasses were associated with both an increase and decrease in community compositional and functional stability. I report the first evidence of native species facilitation decreasing community invasibility. Artemisia facilitation increased native bunchgrass composition, which reduced the magnitude of B. tectorum invasion in under-shrub compared to interspace communities. This decreased invasibility did not translate into lower invasibility at the community level because of the limited spatial scale over which such facilitation occurs. Artemisia facilitation increased community compositional and functional stability at intermediate stress levels but decreased community stability at high stress levels. Facilitation became a destabilizing force when native bunchgrass species became "obligate" beneficiaries, i.e. strongly dependent on Artemisia facilitation for their continued persistence in the community. Structural equation modeling assessed the structure of the causal network and relative importance of factors and processes predicted to drive community invasibility. The linchpin of ecosystem invasibility was the size of and connectivity between basal gaps in perennial vegetation, driven by shifts in the structure and spatial aggregation of the native bunchgrass community. Landscape orientation and soil physical properties determined inherent risk to invasion. Resident bunchgrass and biological soil crust communities provided biotic resistance to invasion by reducing the size of and connectivity between basal gaps and thereby limiting available resources and reducing safe sites for B. tectorum establishment. High levels of cattle grazing reduced ecosystem resilience by reducing native bunchgrass and biological soil crust abundance and altering bunchgrass community composition and facilitated B. tectorum invasion. Conserving and restoring resilience and resistance of these imperiled ecosystems will require reducing cumulative stress levels. As global climate change increases heat and water stress, reducing cumulative cattle grazing intensities by altering utilization rates and/or seasons of use may be the only effective means of accomplishing these goals. Title: Drivers of plant community dynamics in sagebrush steppe ecosystems : cattle grazing, heat and water stress Author: Reisner, Michael D. Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems' resilience to disturbance and invasion by Bromus tectorum (cheatgrass). The role of the foundational shrub Artemisia as a driver of herbaceous community structure and dynamics during this degradation process is poorly understood. Many of the individual factors driving B. tectorum invasions are well documented. However a predictive understanding of the relative importance of complex, interacting factors in the causal network of simultaneously occurring processes determining invasibility has proven elusive. I examined these issues at the landscape level across 75 sites capturing a range of soil and landscape properties and cattle grazing levels similar to those found across the Great Basin. Cumulative cattle herbivory stress levels were a predominant component of both the overlapping heat and water stress gradients driving the structure of Artemisia interactions with herbaceous species. Consistent with the stress gradient hypothesis, Artemisia facilitation of herbaceous species was most frequent and strongest at the highest stress levels, and competition was most frequent and strongest at the lowest stress levels. The two species with the highest competitive response abilities, Elymus elymoides and Poa secunda, showed the strongest facilitation at the upper limits of their stress tolerances. The structure of Artemisia interactions with the invasive B. tectorum was strikingly different than those with native bunchgrasses. Artemisia interactions with native bunchgrasses shifted from competition to facilitation with increasing heat, water, and herbivory stress, but its interactions remained competitive with B. tectorum along the entire stress gradient. Shifts in the structure of interactions between Artemisia and native bunchgrasses were associated with both an increase and decrease in community compositional and functional stability. I report the first evidence of native species facilitation decreasing community invasibility. Artemisia facilitation increased native bunchgrass composition, which reduced the magnitude of B. tectorum invasion in under-shrub compared to interspace communities. This decreased invasibility did not translate into lower invasibility at the community level because of the limited spatial scale over which such facilitation occurs. Artemisia facilitation increased community compositional and functional stability at intermediate stress levels but decreased community stability at high stress levels. Facilitation became a destabilizing force when native bunchgrass species became "obligate" beneficiaries, i.e. strongly dependent on Artemisia facilitation for their continued persistence in the community. Structural equation modeling assessed the structure of the causal network and relative importance of factors and processes predicted to drive community invasibility. The linchpin of ecosystem invasibility was the size of and connectivity between basal gaps in perennial vegetation, driven by shifts in the structure and spatial aggregation of the native bunchgrass community. Landscape orientation and soil physical properties determined inherent risk to invasion. Resident bunchgrass and biological soil crust communities provided biotic resistance to invasion by reducing the size of and connectivity between basal gaps and thereby limiting available resources and reducing safe sites for B. tectorum establishment. High levels of cattle grazing reduced ecosystem resilience by reducing native bunchgrass and biological soil crust abundance and altering bunchgrass community composition and facilitated B. tectorum invasion. Conserving and restoring resilience and resistance of these imperiled ecosystems will require reducing cumulative stress levels. As global climate change increases heat and water stress, reducing cumulative cattle grazing intensities by altering utilization rates and/or seasons of use may be the only effective means of accomplishing these goals. Close

• 40. [Article] Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem

  The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat ...

  Citation × Citation Citation Abstract Copy Title: Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem Author: Epperly, Haley K. The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat and therefore it is important to understand habitat use at all life stages to properly manage the ecosystem, however, few studies have been conducted on the juvenile form. To determine juvenile P. regilla riparian habitat use, and thus create appropriate habitat management plans, field work must be conducted. Transect surveys were conducted at two highly disturbed ephemeral ponds with a variety of open and dense vegetative riparian habitats in the Willamette Valley, Oregon. P. regilla was found in the highest abundance in habitat shaded by a thin border of Oregon Ash around the pond perimeter, and was composed mainly of Himalayan blackberry (Rubus armeniacus). This habitat provided a moist region where P. regilla could avoid desiccation and possibly predation. Rubus armeniacus is non-native and often found in highly disturbed ecosystems. Pseudacris regilla’s use of R. armeniacus as habitat suggests that P. regilla is a generalist species capable of utilizing invasive plant species to its advantage. Future research is needed comparing P. regilla habitat use in invasive-dominated verse native-dominated ephemeral ponds. Title: Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem Author: Epperly, Haley K. The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat and therefore it is important to understand habitat use at all life stages to properly manage the ecosystem, however, few studies have been conducted on the juvenile form. To determine juvenile P. regilla riparian habitat use, and thus create appropriate habitat management plans, field work must be conducted. Transect surveys were conducted at two highly disturbed ephemeral ponds with a variety of open and dense vegetative riparian habitats in the Willamette Valley, Oregon. P. regilla was found in the highest abundance in habitat shaded by a thin border of Oregon Ash around the pond perimeter, and was composed mainly of Himalayan blackberry (Rubus armeniacus). This habitat provided a moist region where P. regilla could avoid desiccation and possibly predation. Rubus armeniacus is non-native and often found in highly disturbed ecosystems. Pseudacris regilla’s use of R. armeniacus as habitat suggests that P. regilla is a generalist species capable of utilizing invasive plant species to its advantage. Future research is needed comparing P. regilla habitat use in invasive-dominated verse native-dominated ephemeral ponds. Close