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• 1. [Article] Aquatic Invasive Species Surveys of Eastern Oregon Waterbodies in 2013 and 2014

  Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Invasive Species Surveys of Eastern Oregon Waterbodies in 2013 and 2014 Author: Miller, Rich, Sytsma, Mark D. Year: 2014 Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish were collected using a thatch rake, benthic dredge, plankton net, and modified minnow traps. Shoreline aquatic noxious weeds were noted when present and water quality characteristics were measured. Two AIS snail species, one AIS crayfish species, and five AIS plant species were detected during the surveys. Big-ear radix snails (Radix auricularia) were newly detected at 14 waterbodies distributed across the survey area. Chinese mystery snails (Cipangopaludina chinensis) were detected in one waterbody. Rusty crayfish (Orconectes rusticus) were newly found at high densities at one lake. AIS plant species included Eurasian watermilfoil (Myriophyllum spicatum), a hybrid of Eurasian with the native northern watermilfoil (M. spicatum x sibiricum), curlyleaf pondweed (Potamogeton crispus), fragrant waterlily (Nymphaea odorata) and reed canarygrass (Phalaris arundinacea). Fifty-six native aquatic plant species were identified in the waterbodies. Water quality conditions ranged from clear, low ionic strength water to highly turbid, productive, high ionic strength water. Title: Aquatic Invasive Species Surveys of Eastern Oregon Waterbodies in 2013 and 2014 Author: Miller, Rich, Sytsma, Mark D. Year: 2014 Early detection aquatic invasive species (AIS) surveys were conducted at 33 Eastern Oregon waterbodies during the summers of 2013 and 2014. Submerged aquatic plants, gastropods, bivalves, and crayfish were collected using a thatch rake, benthic dredge, plankton net, and modified minnow traps. Shoreline aquatic noxious weeds were noted when present and water quality characteristics were measured. Two AIS snail species, one AIS crayfish species, and five AIS plant species were detected during the surveys. Big-ear radix snails (Radix auricularia) were newly detected at 14 waterbodies distributed across the survey area. Chinese mystery snails (Cipangopaludina chinensis) were detected in one waterbody. Rusty crayfish (Orconectes rusticus) were newly found at high densities at one lake. AIS plant species included Eurasian watermilfoil (Myriophyllum spicatum), a hybrid of Eurasian with the native northern watermilfoil (M. spicatum x sibiricum), curlyleaf pondweed (Potamogeton crispus), fragrant waterlily (Nymphaea odorata) and reed canarygrass (Phalaris arundinacea). Fifty-six native aquatic plant species were identified in the waterbodies. Water quality conditions ranged from clear, low ionic strength water to highly turbid, productive, high ionic strength water. Close

• 2. [Article] 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake

  The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included ...

  Citation × Citation Citation Abstract Copy Title: 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake Author: Miller, Rich, Sytsma, Mark D., Brittain, Jeffrey Thomas Year: 2014 The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included in the Project include Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake. The operator of the Project, Portland General Electric (PGE), was issued a license on December 21, 2010 by the Federal Energy Regulatory Commission (FERC) for continued operations and maintenance. The Final Environmental Impact Statement (FEIS) for the license noted that regular surveys for invasive aquatic weed species would be conducted as part of the Project’s Vegetation Management Plan. The term “aquatic weed” is used here to refer to any non-native aquatic plant species. Information from repeated aquatic surveys will help determine native species distributions and the need for treatment of problematic aquatic weed species, particularly hydrilla (Hydrilla verticillata), Brazilian elodea (Egeria densa), and Eurasian watermilfoil (Myriophyllum spicatum). Surveys conducted for PGE by Portland State University (PSU) in Timothy Lake, Lake Harriet, and North Fork Reservoir in 2011 did not locate any problematic submerged or floating leaved aquatic weed species. Earlier surveys of Timothy Lake, and Timothy Lake and Lake Harriet, also indicated the reservoirs were free of aquatic weeds. Heaton et al. (1996) noted that the native species Bidens beckii was present and had the potential to become weedy, however, this species was not found during the 2004 or 2011 surveys. This report covers the results of follow up aquatic vegetation surveys conducted in Lake Harriet, Timothy Lake, and North Fork Reservoir between August 14 and August 21, 2014, as well as new surveys of Faraday Lake and Estacada Lake. Shoreline surveys for emergent invasive species such as yellow flag iris (Iris pseudacorus) and purple loosestrife (Lythrum salicaria) were included in surveys for the first time. Title: 2014 Aquatic Weed Surveys in Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake Author: Miller, Rich, Sytsma, Mark D., Brittain, Jeffrey Thomas Year: 2014 The Clackamas River Hydroelectric Project No. 2195 (Project) is located on the Oak Grove Fork of the Clackamas River and the mainstem of the Clackamas River in Clackamas County, Oregon. Reservoirs included in the Project include Timothy Lake, Lake Harriet, North Fork Reservoir, Faraday Lake, and Estacada Lake. The operator of the Project, Portland General Electric (PGE), was issued a license on December 21, 2010 by the Federal Energy Regulatory Commission (FERC) for continued operations and maintenance. The Final Environmental Impact Statement (FEIS) for the license noted that regular surveys for invasive aquatic weed species would be conducted as part of the Project’s Vegetation Management Plan. The term “aquatic weed” is used here to refer to any non-native aquatic plant species. Information from repeated aquatic surveys will help determine native species distributions and the need for treatment of problematic aquatic weed species, particularly hydrilla (Hydrilla verticillata), Brazilian elodea (Egeria densa), and Eurasian watermilfoil (Myriophyllum spicatum). Surveys conducted for PGE by Portland State University (PSU) in Timothy Lake, Lake Harriet, and North Fork Reservoir in 2011 did not locate any problematic submerged or floating leaved aquatic weed species. Earlier surveys of Timothy Lake, and Timothy Lake and Lake Harriet, also indicated the reservoirs were free of aquatic weeds. Heaton et al. (1996) noted that the native species Bidens beckii was present and had the potential to become weedy, however, this species was not found during the 2004 or 2011 surveys. This report covers the results of follow up aquatic vegetation surveys conducted in Lake Harriet, Timothy Lake, and North Fork Reservoir between August 14 and August 21, 2014, as well as new surveys of Faraday Lake and Estacada Lake. Shoreline surveys for emergent invasive species such as yellow flag iris (Iris pseudacorus) and purple loosestrife (Lythrum salicaria) were included in surveys for the first time. Close

• 3. [Article] Variation in Tussock Architecture of the Invasive Cordgrass Spartina Densiflora along the Pacific Coast of North America

  Some introduced species spread rapidly beyond their native range and into novel habitats mediated by a high degree of phenotypic plasticity and/or rapid evolutionary responses. In this context, clonality ...

  Citation × Citation Citation Abstract Copy Title: Variation in Tussock Architecture of the Invasive Cordgrass Spartina Densiflora along the Pacific Coast of North America Author: Castillo, Jesus M., Grewall, Brenda J., Pickart, Andrea, Figueroa, Enrique, Sytsma, Mark D. Year: 2016 Some introduced species spread rapidly beyond their native range and into novel habitats mediated by a high degree of phenotypic plasticity and/or rapid evolutionary responses. In this context, clonality has been described as a significant factor contributing to invasiveness. We studied the abiotic environment and the responses of different tussock architecture traits of the invasive cordgrass Spartina densiflora Brongn. (Poaceae). A common garden experiment and field studies of S. densiflora in salt marshes across a wide latitudinal gradient from California (USA) to British Columbia (Canada) provided a model system for an integrated study of the potential mechanisms underlying the response of invasive S. densiflora populations to changes in environmental conditions. Our results showed that S. densiflora is able to adjust to widely variable climate (specifically, air temperature and the duration of the growing season) and sediment conditions (specifically, texture and hypoxia) through phenotypical plastic key functional tussock traits (e.g. shoot density, height, above- and below-ground biomass allocation patterns). Root biomass increased in coarser sediments in contrast to rhizomes, which were more abundant in finer sediments. Above-ground biomass and leaf area index increased mainly with air temperature during summer, and more robust (taller and wider) shoots were associated with more oxygenated sediments. In view of our results, S. densifloraappears to be a halophyte with a high degree of phenotypic plasticity that would enable it to respond successfully to changes in the abiotic conditions of salt marshes driven by global climate change, such as increasing salinity and temperatures. Title: Variation in Tussock Architecture of the Invasive Cordgrass Spartina Densiflora along the Pacific Coast of North America Author: Castillo, Jesus M., Grewall, Brenda J., Pickart, Andrea, Figueroa, Enrique, Sytsma, Mark D. Year: 2016 Some introduced species spread rapidly beyond their native range and into novel habitats mediated by a high degree of phenotypic plasticity and/or rapid evolutionary responses. In this context, clonality has been described as a significant factor contributing to invasiveness. We studied the abiotic environment and the responses of different tussock architecture traits of the invasive cordgrass Spartina densiflora Brongn. (Poaceae). A common garden experiment and field studies of S. densiflora in salt marshes across a wide latitudinal gradient from California (USA) to British Columbia (Canada) provided a model system for an integrated study of the potential mechanisms underlying the response of invasive S. densiflora populations to changes in environmental conditions. Our results showed that S. densiflora is able to adjust to widely variable climate (specifically, air temperature and the duration of the growing season) and sediment conditions (specifically, texture and hypoxia) through phenotypical plastic key functional tussock traits (e.g. shoot density, height, above- and below-ground biomass allocation patterns). Root biomass increased in coarser sediments in contrast to rhizomes, which were more abundant in finer sediments. Above-ground biomass and leaf area index increased mainly with air temperature during summer, and more robust (taller and wider) shoots were associated with more oxygenated sediments. In view of our results, S. densifloraappears to be a halophyte with a high degree of phenotypic plasticity that would enable it to respond successfully to changes in the abiotic conditions of salt marshes driven by global climate change, such as increasing salinity and temperatures. Close

• 4. [Article] Efficacy of Plastic Mesh Tubes in Reducing Herbivory Damage by the Invasive Nutria (Myocastor coypus) in an Urban Restoration Site

  The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ...

  Citation × Citation Citation Abstract Copy Title: Efficacy of Plastic Mesh Tubes in Reducing Herbivory Damage by the Invasive Nutria (Myocastor coypus) in an Urban Restoration Site Author: Sheffels, Trevor R., Sytsma, Mark D., Carter, Jacoby, Taylor, Jimmy D. Year: 2014 The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria (Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar® plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar® tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood(Populus balsamifera ssp trichocarpa) over red osier dogwood (Cornus sericea) and willow (Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar® plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes. Title: Efficacy of Plastic Mesh Tubes in Reducing Herbivory Damage by the Invasive Nutria (Myocastor coypus) in an Urban Restoration Site Author: Sheffels, Trevor R., Sytsma, Mark D., Carter, Jacoby, Taylor, Jimmy D. Year: 2014 The restoration of stream corridors is becoming an increasingly important component of urban landscape planning, and the high cost of these projects necessitates the need to understand and address potential ecological obstacles to project success. The nutria (Myocastor coypus) is an invasive, semi-aquatic rodent native to South America that causes detrimental ecological impacts in riparian and wetland habitats throughout its introduced range, and techniques are needed to reduce nutria herbivory damage to urban stream restoration projects. We assessed the efficacy of standard Vexar® plastic mesh tubes in reducing nutria herbivory damage to newly established woody plants. The study was conducted in winter-spring 2009 at Delta Ponds, a 60-ha urban waterway in Eugene, Oregon. Woody plants protected by Vexar® tubes demonstrated 100% survival over the 3-month initial establishment period, while only 17% of unprotected plantings survived. Nutria demonstrated a preference for black cottonwood(Populus balsamifera ssp trichocarpa) over red osier dogwood (Cornus sericea) and willow (Salix spp). Camera surveillance showed that nutria were more active in unprotected rather than protected treatments. Our results suggest that Vexar® plastic mesh tubing can be an effective short-term herbivory mitigation tool when habitat use by nutria is low. Additionally, planting functionally equivalent woody plant species that are less preferred by nutria, and other herbivores, may be another method for reducing herbivory and improving revegetation success. This study highlights the need to address potential wildlife damage conflicts in the planning process for stream restoration in urban landscapes. Close