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• 1. [Article] Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011

  The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. ...

  Citation × Citation Citation Abstract Copy Title: Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011 Author: Sytsma, Mark D., Miller, Rich, Morgan, Vanessa Year: 2011 The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011). Several IAPS classified as noxious have been detected within the Medford District of the Bureau of Land Management (BLM) in Southern Oregon including yellow floating heart (Nymphoides peltata) and yellow flag iris (Iris pseudacorus). During the summers of 2010 and 2011, IAPS surveys were conducted at selected reservoirs, lakes, and river boat launches within the Medford District to determine the extent of IAPS infestations as well as the distributions of native aquatic plant species. This report summarizes results of the surveys and provides recommendations for management of IAPS within the Medford District. Observations of any invasive aquatic animal species such as New Zealand mudsnails (Potamopyrgus antipodarum) are also reported. Title: Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011 Author: Sytsma, Mark D., Miller, Rich, Morgan, Vanessa Year: 2011 The introduction of invasive aquatic plant species (IAPS) can cause significant ecological and economic harm. IAPS can displace native aquatic plant species, impair recreation, and degrade water quality. Early detection of new invasions can improve chances for successful eradication or containment to reduce the risk of IAPS spread. The Oregon Department of Agriculture (ODA) lists the most egregious offenders as “Noxious Weeds” which are defined as plants classified by the Oregon State Weed Board that are injurious to public health, agriculture, recreation, wildlife, or any public or private property (ODA 2011). Several IAPS classified as noxious have been detected within the Medford District of the Bureau of Land Management (BLM) in Southern Oregon including yellow floating heart (Nymphoides peltata) and yellow flag iris (Iris pseudacorus). During the summers of 2010 and 2011, IAPS surveys were conducted at selected reservoirs, lakes, and river boat launches within the Medford District to determine the extent of IAPS infestations as well as the distributions of native aquatic plant species. This report summarizes results of the surveys and provides recommendations for management of IAPS within the Medford District. Observations of any invasive aquatic animal species such as New Zealand mudsnails (Potamopyrgus antipodarum) are also reported. Close

• 2. [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

• 3. [Article] 2005 Diamond Lake Submersed Aquatic Vegetation Survey

  Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern ...

  Citation × Citation Citation Abstract Copy Title: 2005 Diamond Lake Submersed Aquatic Vegetation Survey Author: Sytsma, Mark D., Pfauth, Mary Year: 2006 Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern Cascade Mountains of Oregon, at an elevation of over 5000 feet (>1524 meters). Diamond Lake is a high-use waterbody that supports angling, public campgrounds, recreational boating, swimming, and water skiing. The human activity associated with the lake has been a significant contributor to the economy of southern Oregon since the early part of the twentieth century. Historically Diamond Lake was fishless but since 1910 the lake has been managed as a popular trophy trout fishery. The unauthorized introduction of the tui chub (Gila bicolor) into the lake in the 1930s caused disruption of the food web and a decline in the fishery. In 1954, the Oregon Game Commission constructed a canal near the Lake Creek outlet, lowered the lake level, and treated Diamond Lake with rotenone, to eradicate tui chub. The lake was restocked with trout following the successful rotenone treatment and a fishery was maintained for several decades. In 1992, tui chub were reintroduced, through accidental introduction or intentional illegal stocking, and again caused a decline in the trout fishery. Originally mesotrophic, Diamond Lake Diamond Lake productivity increased over the last century to a eutrophic state, and is currently included on the Oregon Department of Environmental Quality (ODEQ) 303(d) list of water quality limited water bodies for pH and algae. The lake had severe blooms of the cyanobacteria (blue-green algae) Anabaena flos-aquae, which produce neurotoxins, in the summers of 2001, 2002, and 2003. Microcystis aeruginosa, another toxin producing cyanobacterium species, was also present in the 2003 bloom. Diamond Lake was closed to some public uses (wading, swimming, water skiing, and boating) during portions of all three summers due to public health and safety concerns. Algae blooms and declining trout fishery have been attributed to alteration of the food web by the tui chubs. The chubs spawn early and consume the zooplankton in the lake, which reduces grazing pressure on phytoplankton. Since the lake is nitrogen limited, nitrogen-fixing cyanobacteria dominate the phytoplankton community. Therefore, the chubs reduce the quality of the trout fishery by reducing food available for trout and impact water quality by facilitating cyanobacteria blooms, which can be toxic. In response to the impact of the tui chub on Diamond Lake the US Forest Service and Oregon Department of Fish and Wildlife are collaborating in a tui chub eradication effort. The eradication plan includes a 2.4-m (8 ft) drawdown of the lake in the winter and spring of 2006 and a rotenone treatment of remaining lake volume in 2006 to kill any remaining fish. The US Forest Service prepared an EIS for the drawdown and rotenone treatment. Potential impacts of the drawdown on littoral aquatic plant communities were identified in the EIS. The US Forest Service conducted a qualitative survey to develop a species list for the lake. The survey described here provides a quantitative, pretreatment measure of cover and biomass of aquatic plants in Diamond Lake. Follow-up sampling, using similar methods, will permit assessment of changes in the plant community following drawdown and refilling of the lake. Title: 2005 Diamond Lake Submersed Aquatic Vegetation Survey Author: Sytsma, Mark D., Pfauth, Mary Year: 2006 Diamond Lake is a large natural lake having a surface area of some 3214 acres (1300.7 hectares) and a maximum depth of 52 feet (15.8 meters). It is located within the Umpqua National Forest in the Southern Cascade Mountains of Oregon, at an elevation of over 5000 feet (>1524 meters). Diamond Lake is a high-use waterbody that supports angling, public campgrounds, recreational boating, swimming, and water skiing. The human activity associated with the lake has been a significant contributor to the economy of southern Oregon since the early part of the twentieth century. Historically Diamond Lake was fishless but since 1910 the lake has been managed as a popular trophy trout fishery. The unauthorized introduction of the tui chub (Gila bicolor) into the lake in the 1930s caused disruption of the food web and a decline in the fishery. In 1954, the Oregon Game Commission constructed a canal near the Lake Creek outlet, lowered the lake level, and treated Diamond Lake with rotenone, to eradicate tui chub. The lake was restocked with trout following the successful rotenone treatment and a fishery was maintained for several decades. In 1992, tui chub were reintroduced, through accidental introduction or intentional illegal stocking, and again caused a decline in the trout fishery. Originally mesotrophic, Diamond Lake Diamond Lake productivity increased over the last century to a eutrophic state, and is currently included on the Oregon Department of Environmental Quality (ODEQ) 303(d) list of water quality limited water bodies for pH and algae. The lake had severe blooms of the cyanobacteria (blue-green algae) Anabaena flos-aquae, which produce neurotoxins, in the summers of 2001, 2002, and 2003. Microcystis aeruginosa, another toxin producing cyanobacterium species, was also present in the 2003 bloom. Diamond Lake was closed to some public uses (wading, swimming, water skiing, and boating) during portions of all three summers due to public health and safety concerns. Algae blooms and declining trout fishery have been attributed to alteration of the food web by the tui chubs. The chubs spawn early and consume the zooplankton in the lake, which reduces grazing pressure on phytoplankton. Since the lake is nitrogen limited, nitrogen-fixing cyanobacteria dominate the phytoplankton community. Therefore, the chubs reduce the quality of the trout fishery by reducing food available for trout and impact water quality by facilitating cyanobacteria blooms, which can be toxic. In response to the impact of the tui chub on Diamond Lake the US Forest Service and Oregon Department of Fish and Wildlife are collaborating in a tui chub eradication effort. The eradication plan includes a 2.4-m (8 ft) drawdown of the lake in the winter and spring of 2006 and a rotenone treatment of remaining lake volume in 2006 to kill any remaining fish. The US Forest Service prepared an EIS for the drawdown and rotenone treatment. Potential impacts of the drawdown on littoral aquatic plant communities were identified in the EIS. The US Forest Service conducted a qualitative survey to develop a species list for the lake. The survey described here provides a quantitative, pretreatment measure of cover and biomass of aquatic plants in Diamond Lake. Follow-up sampling, using similar methods, will permit assessment of changes in the plant community following drawdown and refilling of the lake. Close