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Rangelands have immense inherent spatial and temporal variability, yet assessments of land condition and trends are often assessed relative to the condition of a limited number of representative points. Ecological Potential (EP) data are spatially comprehensive, quantitative, and needed as a baseline for comparison of current rangeland vegetation conditions, trends, and management targets. We define EP as the potential fractional cover of vegetation components bare ground, herbaceous, litter, shrub, and sagebrush represented in the least disturbed and most productive portion of the western U.S. This dataset enables: 1) setting realistic expectations for restoration and management targets at 30-meter resolution,...
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This data release presents catch and effort data for Cisco Coregonus artedi and Lake Whitefish Coregonus clupeaformis commercial gill net fisheries in State of Michigan waters of Lakes Superior, Michigan, and Huron during 1929-1970. The data were used to determine if Cisco and Lake Whitefish relative abundance (commercial gill net catch per effort) were correlated (positive and negative) during the historical period. The file is in .csv format and contains columns for: (1) lake (LAKE); (2) commercial fishery management unit (MU); (3) year (YEAR); (4) gill net material used to target Lake Whitefish (WF_MAT); (5) gill net material used to target Cisco (CS_MAT); (6) gill net conversion factors (multipliers) used...
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Water primrose (Ludwigia hexapetala) is an invasive aquatic plant that has rapidly increased in coverage throughout the Sacramento-San Joaquin Delta. Water primrose has invaded wetlands and may contribute towards mortality of tules (Schoenoplectus spp.) and cattails (Typha spp.). Little research has been completed on the mechanisms responsible for marsh loss, but previous studies have suggested that water primrose contains allelopathic chemicals that could cause plant mortality. Three major allelopathic polyphenols (myricitrin, prunin, and quercitrin) previously identified in L. hexapetala leaves were measured in leaf, water, and soil samples from Delta marshes infested with water primrose. Samples were collected...
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This dataset provides location and standard measurements of captured Cuban Treefrogs from the Audubon Park and Zoo area of New Orleans, Louisiana.
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The primary objective of this study was to assess deepsea food web structure and trophic niches in Baltimore and Norfolk canyons, the adjacent slopes, and chemosynthetic seeps along the mid-Atlantic margin using stable isotope analyses (SIA) and isotope niche width analysis. We hypothesized that the isotopic compositions of canyon versus slope fauna would be distinct, given differences in the physics and chemistry of the canyons and slopes and resulting quality and quantity of the organic matter available to the benthos. These differences should be evident across taxa and among and within feeding groups. We also used SIA to estimate trophic positions of invertebrates and fishes and to examine changes in trophic...
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These data were compiled to allow examination of northern spotted owl territorial occupancy dynamics, especially with regards to the roles played by habitat and competition with barred owl in past and future dynamics. Data are estimates of parameters derived from previous modelling of northern spotted owl territorial occupancy dynamics. These data were collected as part of monitoring of northern spotted owl demography. Associated code allows analysis of these estimates to understand the roles of competition and habitat in recent northern spotted owl declines and to predict the future of northern spotted owl under various management scenarios.
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A fish’s diet is the integrated response of multiple ecological interactions including habitat use, foraging behavior, prey community characteristics, and inter-specific interactions. Fish diet samples have quantified how the invasion of white perch into Lake Erie in the early 1950s has influenced interactions with native yellow perch, which are similar in morphology and habitat use. Early research largely concluded that given the high foraging efficiency of white perch there is both high potential for inter-specific competition and that the invasion of white perch has negatively affected yellow perch. As part of a biannual (spring and autumn) Lake Erie Western Basin Forage Fish Assessment, the USGS Lake Erie Biological...
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In 1990 the US Geological Survey Fort Collins Science Center and National Park Service Water Resources Division established 133 permanent 1meter (m) X 2 m plots along the Gunnison River near Warner Point in Black Canyon of the Gunnison National Park. A one-dimensional hydraulic model was calibrated to determine the inundation necessary to inundate each plot, and this can be combined with daily flow data to determine the inundation duration or percentage of time a plot is under water. Occurrence of all plant species in these plots was determined in late July of 1990, 1994, 2001, 2006 and 2013. This data set includes 3 csv files of plot data. One file gives characteristics of plots, including plot name, inundating...


    map background search result map search result map Food-web structure of canyon and slope associated fauna revealed by stable isotopes Body measurements of the exotic invasive Cuban treefrog (Osteopilus septentrionalis) in Louisiana Northern spotted owl data and analysis code, Cascade Range, Pacific Northwest, USA Diet Data from the Western Basin of Lake Erie Examining White and Yellow Perch, 2012-2016 Ecological Potential Fractional Component Cover Based on Long-Term Satellite Observations Across the Western United States Catch and Effort Data for Cisco and Lake Whitefish Commercial Gill Net Fisheries in State of Michigan Waters of Lakes Superior, Michigan, and Huron During 1929–1970 Occurrence of plants in plots along the Gunnison River, Colorado, 1990-2017 Analysis of Polyphenols in Water Primrose (Ludwigia hexapetala) Plants from the Sacramento-San Joaquin Delta of California Occurrence of plants in plots along the Gunnison River, Colorado, 1990-2017 Body measurements of the exotic invasive Cuban treefrog (Osteopilus septentrionalis) in Louisiana Analysis of Polyphenols in Water Primrose (Ludwigia hexapetala) Plants from the Sacramento-San Joaquin Delta of California Diet Data from the Western Basin of Lake Erie Examining White and Yellow Perch, 2012-2016 Food-web structure of canyon and slope associated fauna revealed by stable isotopes Northern spotted owl data and analysis code, Cascade Range, Pacific Northwest, USA Catch and Effort Data for Cisco and Lake Whitefish Commercial Gill Net Fisheries in State of Michigan Waters of Lakes Superior, Michigan, and Huron During 1929–1970 Ecological Potential Fractional Component Cover Based on Long-Term Satellite Observations Across the Western United States