55 research outputs found

    Aquatic Invasive Species Surveys of Upper Klamath Lake, Fourmile Lake, and Lake of the Woods, OR During 2012

    Get PDF
    Three lakes located within the Klamath River Basin in Oregon (Upper Klamath Lake, Fourmile Lake, and Lake of the Woods) were surveyed for aquatic invasive species during the summer of 2012. Specimens were collected using plant rakes, benthic dredges, plankton nets, and crayfish traps. No invasive aquatic plants, gastropods, snails, bivalves or crayfish were detected in the lakes

    Inventory and Mapping of Aquatic Plants at Lake Roosevelt National Recreation Area

    Get PDF
    Lake Roosevelt is a large reservoir in northeast Washington State formed by the Grand Coulee Dam. The reservoir, which inundates portions of the Columbia River, the Spokane River, and other rivers and streams, is the focus of the Lake Roosevelt National Recreation Area (LARO) that is managed by the National Park Service. LARO encompasses 100,390 acres (40,625 ha) and includes significant cultural and recreational resources. The surface area, volume, and shoreline length of Lake Roosevelt at full pool is 82,691 acres (33,490 ha), 9.41 × 1010 acre-ft (1.16 × 1010 m3) (Nigro et. al. 1981), and 630 miles (1014 km) (www.lrf.org/AboutLR/ALRFastFacts.html accessed 28 January 2008), respectively; thus, the reservoir provides a significant aquatic resource for fish and wildlife as well as recreation in the region. Invasive plants are a high-priority “vital sign” of LARO ecosystem health (Garret et. al. 2007). In recent years, LARO staff noted an increase in the density of submersed aquatic plants (macrophytes), including Myriophyllum spicatum (Eurasian watermilfoil), in the lake. M. spicatum is a highly invasive weed that forms dense surface mats that interfere with boating and angling and degrade water quality. In an effort to reduce recreational impacts of aquatic plants LARO staff established test plots of nonchemical methods of control during the drawdown period in the spring of 2007. The National Park Service contracted Portland State University Center for Lakes and Reservoirs to accomplish two main objectives: 1) document the effects of nonchemical control measures of submersed aquatic plants in the reservoir, and 2) describe the composition of the aquatic plant community at selected locations in LARO

    Zebra and Quagga Mussel Early-Detection Monitoring in High Risk Oregon Waters 2014

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

    Aquatic Plant Surveys in the Bureau of Land Management, Medford District, 2010-2011

    Get PDF
    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

    Aquatic Invasive Plant Surveys in the BLM Medford District During 2012

    Get PDF
    Aquatic plant surveys were conducted at 22 waterbodies located within the Bureau of Land Management’s Medford District during the summer of 2012. Sites included eleven lakes, ponds or reservoirs and six reaches along the Rogue and Applegate Rivers. Five sampling areas surveyed during 2010 and 2011 were revisited to determine the extent of known non-native species infestations, positively identify rare species, or verify the absence of an expected non-native species. Plant specimens were collected at up to 50 sites at each waterbody using plant rakes or by observation. The non-native submersed species curly leaf pondweed (Potamogeton crispus) and Eurasian x northern watermilfoil (Myriophyllum sibiricum x spicatum) were widespread throughout the District. Eurasian watermilfoil (Myriophyllum spicatum) was present at two sites. Emergent non-native aquatic species included parrotsfeather (Myriophyllum aquaticum), yellow flag iris (Iris pseudacorus), purple loosestrife (Lythrum salicaria), reed canary grass (Phalaris arundinaceae), floating primrose-willow (Ludwigia peploides) and slender waternymph (Najas gracillima)

    Dreissenid Mussel Research Priorities Workshop

    Get PDF
    Currently, dreissenid mussels have yet to be detected in the northwestern part of the United States and western Canada. Infestation of one of the jurisdictions within the mussel-free Pacific Northwest would likely have significant economic, soci­etal and environmental implications for the entire region. Understanding the biology and environmental tolerances of dreissenid mussels, and effectiveness of various man­agement strategies, is key to prevention. On November 4-5, 2015, the Aquatic Bioinvasion Research and Policy Institute and the Center for Lakes and Reservoirs at Portland State University, the US Geological Survey, and the Pacific States Marine Fisheries Commission, convened a Dreissenid Mussel Research Priorities Workshop funded by the Great Northern Landscape Conservation Cooperative. The purpose of the workshop was to review dreissenid research priorities in the 2010 Quagga-Zebra Mussel Action Plan for Western U.S. Waters, reassess those priorities, incorporate new information and emerging trends, and develop priorities to strategically focus research efforts on zebra and quagga mussels in the Pacific Northwest and ensure that future research is focused on the highest priorities. It is important to note that there is some repetition among dreissenid research priority categories (e.g., prevention, detection, control, monitoring, and biology). Workshop participants with research experience in dreissenid mussel biology and management were identified by a literature review. State and federal agency managers were also invited to the workshop to ensure relevancy and practicality of the work­shop outcomes. A total of 28 experts (see sidebar) in mussel biology, ecology, and management attended the workshop

    Aquatic Invasive Species Surveys of Pacificorp’s North Umpqua River Impoundments

    Get PDF
    Ten North Umpqua Hydroelectric Project impoundments were surveyed for aquatic invasive species during the summer of 2012. One non-native submersed aquatic vegetation species (Potamogeton crispus) and one non-native snail species (Radix auricularia) was detected. No crayfish or mussel veligers were collected and no non-native zooplankton species were encountered

    Physical, Chemical and Biological Assessment of Yoncalla Log Ponds

    Get PDF
    The Yoncalla Log Ponds are a series of four ponds located in within the city limits of the town in Yoncalla in northern Douglas County, Oregon. The ponds were created in stages between the late 1930s and the 1950s and used for log storage through the 1970s (North Douglas Betterment 2014). North Douglas Betterment purchased the land surrounding the ponds and contracted with the Center for Lakes and Reservoirs at Portland State University to assess the current morphometry, vegetation and water quality status of the ponds and provide recommendations for management of the aquatic vegetation. The scope of this document covers the current status assessment of the ponds using data collected from June 2013 through May 2014

    Middle Columbia River Aquatic Nuisance Species Survey

    Get PDF
    Aquatic nonindigenous species (ANS) in the middle Columbia and lower Snake rivers were surveyed during the summer of 2006. The project area included eight reservoirs and the free-flowing, Hanford Reach on the Columbia River. We also conducted a literature review to create a complete list of ANS for the study area

    Hydroacoustic Survey and Point Sampling of Macrophytes In Diamond Lake 2009

    Get PDF
    MaxDepth Aquatics, Inc. was contracted to conduct a hydroacoustic survey of macrophyte distribution in Diamond Lake in 2009. The survey essentially repeated surveys conducted in 2002 and 2007, allowing for a detailed assessment of conditions in 2009 and comparisons among previous years. In addition, Portland State University was contracted to conduct a depth stratified random point sample survey of macrophyte species presence and absence. The point sample survey was similar to surveys conducted in 2005 and 2007. The results of the 2009 hydroacoustic survey showed that macrophytes were widely distributed throughout the lake at depths less than 8 meters, although some shorter aggregations of macrophytes were found at depths down to 14 meters. Average canopy height corresponded closely to macrophyte density in 2009. The recent survey showed that macrophytes had extended deeper throughout the lake compared to 2002 and 2007 and that canopy height had increased substantially in some locations. The 2009 distribution showed that recolonization of the near shore areas was proceeding, albeit at a relatively slow pace since the lake drawdown completed in 2006. The maximum density of macrophytes in 2009 was found between 4 to 6 meters. Five macrophyte species, one macroalgal species, and filamentous algae were present in the 2009 random point survey. The occurrence rates of the macrophytes Elodea canadensis, Ceratophyllum demersum, and Potamogeton praelongus in 2009 were similar to 2005 and 2007 while Potamogeton pusillus occurrence increased and Myriophyllum verticillatum decreased. Macrophytes were present in a few samples greater than 9 meters; however, biomass, as measured by the fullness of a sampling rake, was highest between 2 and 6 meters. The comparison of the grab sampling conducted in August with the hydroacoustic survey in early September showed poor correspondence in macrophyte density obtained by the two methods. This is likely due to differences in spatial scales of collected samples (10 m2 grid for hydroacoustics compared to \u3c 1 m2 grab samples), comparison of a continuous analytic tool (hydroacoustic) versus an ordinal ranking of density (rake), and possibly some changes in the macrophytes community between the two sampling dates
    • …
    corecore