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At least 1,549 records · Page 86Linked to original sources
USGS2008

Airborne Hyperspectral Survey of Afghanistan 2007: Flight Line Planning and HyMap Data Collection

Hyperspectral remote sensing data were acquired over Afghanistan with the HyMap imaging spectrometer (Cocks and others, 1998) operating on the WB-57 high altitude NASA research aircraft (http://jsc-aircraft-ops.jsc.nasa.gov/wb57/index.html). These data were acquired during the interval of August 22, 2007 to October 2, 2007, as part of the United States Geological Survey (USGS) project 'Oil and Gas Resources Assessment of the Katawaz and Helmand Basins'. A total of 218 flight lines of hyperspectral remote sensing data were collected over the country. This report describes the planning of the airborne survey and the flight lines that were flown. Included with this report are digital files of the nadir tracks of the flight lines, including a map of the labeled flight lines and corresponding vector shape files for geographic information systems (GIS).

Open-File Report↗
USGS2008

Avian Species Inventory at Manzanar National Historic Site, California - Final Report to the National Park Service

We conducted a baseline inventory for avian species at Manzanar National Historic Site, Inyo County, Calif., from 2002 to 2005. Under the guidelines of the Mojave Network Biological Inventory Program, the primary objectives for this study were to (1) inventory and document the occurrence of avian species at Manzanar, with the goal of documenting at least 90 percent of the species present; (2) provide a geographic information system (GIS)-referenced list of sensitive species occurring at Manzanar that are rare, on Federal or State lists, or otherwise worthy of special consideration; and (3) enter all species data into the National Park Service NPSpecies database. Survey methods included general area searches, variable circular plot point-count censusing, nocturnal surveys, and nest searching. During 13 year-round survey sessions, we documented the occurrence of 132 bird species at Manzanar and confirmed breeding by 19 of these. Based on our findings, as well as review of the literature and searches for records of species occurrence, we estimate inventory completeness for regularly occurring bird species at Manzanar to be near 90 percent. No sensitive species on Federal or State lists were found. The distribution and relative abundance of common bird species at this site is now well enough known to begin development of a monitoring protocol for this group.

Open-File Report↗
USGS2008

Inventory of Data Sources Used for Watershed Condition Assessments of Fire Island National Seashore, Gateway National Recreation Area, and Sagamore Hill National Historic Site, New York and New Jersey

The natural resources and watershed conditions of National Park units in the New York-New Jersey area - Gateway National Recreation Area (GATE), Sagamore Hill National Historic Site (SAHI), and Fire Island National Seashore (FIIS) - are threatened by different degrees of urbanization and direct or indirect human use. Such threats as nutrient enrichment, sedimentation, exotic species invasion, water pollution, and development pose serious management concerns for these parks. Limited investigations of the status of different natural resources at or near each park have been conducted, but a comprehensive understanding of the natural resources and watershed conditions at FIIS, GATE, and SAHI is needed. This report details the sources of spatial data and metadata assembled into a Geographic Information System (GIS) for the purpose of assessing natural resources and watershed conditions at GATE, SAHI, and FIIS.

Open-File Report↗
USGS2008

Flood of June 7-9, 2008, in Central and Southern Indiana

On June 6-7, 2008, heavy rainfall of 2 to more than 10 inches fell upon saturated soils and added to already high streamflows from a wetter than normal spring in central and southern Indiana. The heavy rainfall resulted in severe flooding on many streams within the White River Basin during June 7-9, causing three deaths, evacuation of thousands of residents, and hundreds of millions of dollars of damage to residences, businesses, infrastructure, and agricultural lands. In all, 39 Indiana counties were declared Federal disaster areas. U.S. Geological Survey (USGS) streamgages at nine locations recorded new record peak streamflows for the respective periods of record as a result of the heavy rainfall. Recurrence intervals of flood-peak streamflows were estimated to be greater than 100 years at five streamgages and 50-100 years at two streamgages. Peak-gage-height data, peak-streamflow data, and recurrence intervals are tabulated for 19 USGS streamgages in central and southern Indiana. Peak-streamflow estimates are tabulated for four ungaged locations, and estimated recurrence intervals are tabulated for three ungaged locations. The estimated recurrence interval for an ungaged location on Haw Creek in Columbus was greater than 100 years and for an ungaged location on Hurricane Creek in Franklin was 50-100 years. Because flooding was particularly severe in the communities of Columbus, Edinburgh, Franklin, Paragon, Seymour, Spencer, Martinsville, Newberry, and Worthington, high-water-mark data collected after the flood were tabulated for those communities. Flood peak inundation maps and water-surface profiles for selected streams were made in a geographic information system by combining the high-water-mark data with the highest-resolution digital elevation model data available.

Open-File Report↗
USGS2008

Streamflow and Endangered Species Habitat in the Lower Isleta Reach of the Middle Rio Grande

San Acacia Dam is located in a reach of the Rio Grande that has been designated as critical habitat for two endangered species, the Rio Grande silvery minnow (Hybognathus amarus) and the southwestern willow flycatcher (Empidonax traillii extimus). Under present operations, the Rio Grande upstream from the dam is used to convey irrigation water to the Socorro main canal at San Acacia Dam. In order to increase operational flexibility and improve irrigation delivery efficiency, the 'Bernardo Siphon' has been proposed to intercept up to 150 cubic feet per second from the Lower San Juan Riverside Drain on the east side of the Rio Grande and transport it under the river into a drainage canal on the west side. Irrigation deliveries to the Socorro main canal would be conveyed by way of the drainage canal rather than the Rio Grande. The objective of this study was to provide the Bureau of Reclamation (BOR) and other stakeholders with a tool to evaluate the effects of different operational modes of the Bernardo siphon on habitat for H. amarus and E. t. extimus in this section of river. We used a two-dimensional hydraulic simulation model to simulate hydraulic conditions for a range of discharges at three study sites in the Rio Grande between the proposed siphon location and San Acacia Dam. Suitable habitat characteristics were defined for H. amarus by consensus of a panel of experts and for E. t. extimus on the basis of a study conducted in 2003 by BOR. Habitat suitability maps for each targeted life stage and simulated discharge were constructed using a Geographic Information System (ArcGIS) and the results compiled into tables relating discharge to areas of suitable habitat. A separate analysis was conducted to calculate an index of connectivity among habitat patches at low flows. A hydrologic model was constructed to synthesize flows, by reach, without the siphon, which was used as a baseline for comparison with similarly-synthesized discharges with the siphon under different operating rules. Results from the hydrologic time series were combined with the discharge-habitat relations to develop habitat time series models, statistics, and scoring metrics for comparisons of alternative rules of operation for the Bernardo siphon. Suitable habitat for H. amarus was defined as areas having suitable hydraulic conditions alone and as areas having suitable hydraulics in association with large woody debris. Suitable hydraulic habitat for adults was maximized at discharges between 40 and 80 cubic feet per second, and declined rapidly at discharges larger than 150 cubic feet per second. When large woody debris was included in the definition of suitable habitat, discharges between 40 and 200 cubic feet per second provided maximum suitable habitat for adults. Juvenile hydraulic habitat was maximized at discharges between 20 and 80 cubic feet per second, and hydraulic habitat associated with large woody debris was largest at flows between 40 and 150 cubic feet per second. Nesting habitat area for E. t. extimus increased monotonically at discharges larger than 5 ft3/s, but decreased rapidly below that flow.

Open-File Report↗
USGS2009

Digital Data from the Great Sand Dunes and Poncha Springs Aeromagnetic Surveys, South-Central Colorado

This report contains digital data, image files, and text files describing data formats and survey procedures for two high-resolution aeromagnetic surveys in south-central Colorado: one in the eastern San Luis Valley, Alamosa and Saguache Counties, and the other in the southern Upper Arkansas Valley, Chaffee County. In the San Luis Valley, the Great Sand Dunes survey covers a large part of Great Sand Dunes National Park and Preserve and extends south along the mountain front to the foot of Mount Blanca. In the Upper Arkansas Valley, the Poncha Springs survey covers the town of Poncha Springs and vicinity. The digital files include grids, images, and flight-line data. Several derivative products from these data are also presented as grids and images, including two grids of reduced-to-pole aeromagnetic data and data continued to a reference surface. Images are presented in various formats and are intended to be used as input to geographic information systems, standard graphics software, or map plotting packages.

Open-File Report↗
USGS2009

Methods for Estimating Withdrawal and Return Flow by Census Block for 2005 and 2020 for New Hampshire

The U.S. Geological Survey, in cooperation with the New Hampshire Department of Environmental Services, estimated the amount of water demand, consumptive use, withdrawal, and return flow for each U.S. Census block in New Hampshire for the years 2005 (current) and 2020. Estimates of domestic, commercial, industrial, irrigation, and other nondomestic water use were derived through the use and innovative integration of several State and Federal databases, and by use of previously developed techniques. The New Hampshire Water Demand database was created as part of this study to store and integrate State of New Hampshire data central to the project. Within the New Hampshire Water Demand database, a lookup table was created to link the State databases and identify water users common to more than one database. The lookup table also allowed identification of withdrawal and return-flow locations of registered and unregistered commercial, industrial, agricultural, and other nondomestic users. Geographic information system data from the State were used in combination with U.S. Census Bureau spatial data to locate and quantify withdrawals and return flow for domestic users in each census block. Analyzing and processing the most recently available data resulted in census-block estimations of 2005 water use. Applying population projections developed by the State to the data sets enabled projection of water use for the year 2020. The results for each census block are stored in the New Hampshire Water Demand database and may be aggregated to larger political areas or watersheds to assess relative hydrologic stress on the basis of current and potential water availability.

Open-File Report↗
USGS2009

Petrified Forest National Park Invasive Plant Species Survey and Mapping; 2002-2005

We conducted a survey for invasive nonnative plant species at Petrified Forest National Park from 2002 through 2005. The survey employed a unique sampling design consisting of a grid of consecutive one-hectare cells as the sampling units. Our use of predetermined sampling units allowed all observations to be referenced to a fixed area with geographic coordinates that easily transferred to a geographic information system. Our field team surveyed 2,730 sampling units in three select areas for at least 1 year and 879 sampling units for 4 years. During this period we identified 40 different invasive plant species; more than half the invasive plants (22 species) were annual forbs and grasses. Four invasive plant species occurred in 25 percent or more of all sampling units observed in one or more years: Bromus tectorum, Erodium cicutarium, Salsola tragus, and Sisymbrium altissimum. Salsola tragus was the most abundant species in all years and occurred in more than 55 percent of all sampling units surveyed each year.

Open-File Report↗
USGS2010

A Review of Aeromagnetic Anomalies in the Sawatch Range, Central Colorado

This report contains digital data and image files of aeromagnetic anomalies in the Sawatch Range of central Colorado. The primary product is a data layer of polygons with linked data records that summarize previous interpretations of aeromagnetic anomalies in this region. None of these data files and images are new; rather, they are presented in updated formats that are intended to be used as input to geographic information systems, standard graphics software, or map-plotting packages.

Open-File Report↗
USGS2010

Flood of September 2008 in Northwestern Indiana

During September 12-15, 2008, rainfall ranging from 2 to more than 11 inches fell on northwestern Indiana. The rainfall resulted in extensive flooding on many streams within the Lake Michigan and Kankakee River Basins during September 12-18, causing two deaths, evacuation of hundreds of residents, and millions of dollars of damage to residences, businesses, and infrastructure. In all, six counties in northwestern Indiana were declared Federal disaster areas. U.S. Geological Survey (USGS) streamgages at four locations recorded new record peak streamflows as a result of the heavy rainfall. Peak-gage-height data, peak-streamflow data, annual exceedance probabilities, and recurrence intervals are tabulated in this report for 10 USGS streamgages in northwestern Indiana. Recurrence intervals of flood-peak streamflows were estimated to be greater than 100 years at six streamgages. Because flooding was particularly severe in the communities of Munster, Dyer, Hammond, Highland, Gary, Lake Station, Hobart, Schererville, Merrillville, Michiana Shores, and Portage, high-water-park data collected after the flood were tabulated for those communities. Flood peak inundation maps and water-surface profiles for selected streams were made in a geographic information system by combining high-water-mark data with the highest resolution digital elevation model data available.

Indiana↗
USGS2010

Preliminary assessment of factors influencing riverine fish communities in Massachusetts

The U.S. Geological Survey, in cooperation with the Massachusetts Department of Conservation and Recreation (MDCR), Massachusetts Department of Environmental Protection (MDEP), and the Massachusetts Department of Fish and Game (MDFG), conducted a preliminary investigation of fish communities in small- to medium-sized Massachusetts streams. The objective of this investigation was to determine relations between fish-community characteristics and anthropogenic alteration, including flow alteration and impervious cover, relative to the effect of physical basin and land-cover (environmental) characteristics. Fish data were obtained for 756 fish-sampling sites from the Massachusetts Division of Fisheries and Wildlife fish-community database. A review of the literature was used to select a set of fish metrics responsive to flow alteration. Fish metrics tested include two fish-community metrics (fluvial-fish relative abundance and fluvial-fish species richness), and five indicator species metrics (relative abundance of brook trout, blacknose dace, fallfish, white sucker, and redfin pickerel). Streamflows were simulated for each fish-sampling site using the Sustainable Yield Estimator application (SYE). Daily streamflows and the SYE water-use database were used to determine a set of indicators of flow alteration, including percent alteration of August median flow, water-use intensity, and withdrawal and return-flow fraction. The contributing areas to the fish-sampling sites were delineated and used with a Geographic Information System (GIS) to determine a set of environmental characteristics, including elevation, basin slope, percent sand and gravel, percent wetland, and percent open water, and a set of anthropogenic-alteration variables, including impervious cover and dam density. Two analytical techniques, quantile regression and generalized linear modeling, were applied to determine the association between fish-response variables and the selected environmental and anthropogenic explanatory variables. Quantile regression indicated that flow alteration and impervious cover were negatively associated with both fluvial-fish relative abundance and fluvial-fish species richness. Three generalized linear models (GLMs) were developed to quantify the response of fish communities to multiple environmental and anthropogenic variables. Flow-alteration variables are statistically significant for the fluvial-fish relative-abundance model. Impervious cover is statistically significant for the fluvial-fish relative-abundance, fluvial-fish species richness, and brook trout relative-abundance models. The variables in the equations were demonstrated to be significant, and the variability explained by the models, as measured by the correlation between observed and predicted values, ranges from 39 to 65 percent. The GLM models indicated that, keeping all other variables the same, a one-unit (1 percent) increase in the percent depletion or percent surcharging of August median flow would result in a 0.4-percent decrease in the relative abundance (in counts per hour) of fluvial fish and that the relative abundance of fluvial fish was expected to be about 55 percent lower in net-depleted streams than in net-surcharged streams. The GLM models also indicated that a unit increase in impervious cover resulted in a 5.5-percent decrease in the relative abundance of fluvial fish and a 2.5-percent decrease in fluvial-fish species richness.

Massachusetts↗
USGS2010

Social values for ecosystem services (SolVES): A GIS application for assessing, mapping, and quantifying the social values of ecosystem services-Documentation and user manual, version 1.0

In response to the need for incorporating quantified and spatially explicit measures of social values into ecosystem services assessments, the Rocky Mountain Geographic Science Center, in collaboration with Colorado State University, has developed a geographic information system application, Social Values for Ecosystem Services (SolVES). SolVES can be used to assess, map, and quantify the perceived social values of ecosystem services. SolVES derives a quantitative social values metric, the Value Index, from a combination of spatial and nonspatial responses to public attitude and preference surveys. SolVES also generates landscape metrics, such as average elevation and distance to water, calculated from spatial data layers describing the underlying physical environment. Using kernel density calculations and zonal statistics, SolVES derives and maps the 10-point Value Index and reports landscape metrics associated with each index value for social value types such as aesthetics, biodiversity, and recreation. This can be repeated for various survey subgroups as distinguished by their attitudes and preferences regarding public uses of the forests such as motorized recreation and logging for fuels reduction. The Value Index provides a basis of comparison within and among survey subgroups to consider the effect of social contexts on the valuation of ecosystem services. SolVES includes regression coefficients linking the predicted value (the Value Index) to landscape metrics. These coefficients are used to generate predicted social value maps using value transfer techniques for areas where primary survey data are not available. SolVES was developed, and will continue to be enhanced through future versions, as a public domain tool to enable decision makers and researchers to map the social values of ecosystem services and to facilitate discussions among diverse stakeholders regarding tradeoffs between different ecosystem services in a variety of physical and social contexts.

Open-File Report↗
USGS2011

Moderate-resolution sea surface temperature data for the nearshore North Pacific

Coastal sea surface temperature (SST) is an important environmental characteristic in determining the suitability of habitat for nearshore marine and estuarine organisms. This publication describes and provides access to an easy-to-use coastal SST dataset for ecologists, biogeographers, oceanographers, and other scientists conducting research on nearshore marine habitats or processes. The data cover the Temperate Northern Pacific Ocean as defined by the 'Marine Ecosystems of the World' (MEOW) biogeographic schema developed by The Nature Conservancy. The spatial resolution of the SST data is 4-km grid cells within 20 km of the shore. The data span a 29-year period - from September 1981 to December 2009. These SST data were derived from Advanced Very High Resolution Radiometer (AVHRR) instrument measurements compiled into monthly means as part of the Pathfinder versions 5.0 and 5.1 (PFSST V50 and V51) Project. The processing methods used to transform the data from their native Hierarchical Data Format Scientific Data Set (HDF SDS) to georeferenced, spatial datasets capable of being read into geographic information systems (GIS) software are explained. In addition, links are provided to examples of scripts involved in the data processing steps. The scripts were written in the Python programming language, which is supported by ESRI's ArcGIS version 9 or later. The processed data files are also provided in text (.csv) and Access 2003 Database (.mdb) formats. All data except the raster files include attributes identifying realm, province, and ecoregion as defined by the MEOW classification schema.

Open-File Report↗
USGS2010

National Water-Quality Assessment (NAWQA) area-characterization toolbox

This is release 1.0 of the National Water-Quality Assessment (NAWQA) Area-Characterization Toolbox. These tools are designed to be accessed using ArcGIS Desktop software (versions 9.3 and 9.3.1). The toolbox is composed of a collection of custom tools that implement geographic information system (GIS) techniques used by the NAWQA Program to characterize aquifer areas, drainage basins, and sampled wells. These tools are built on top of standard functionality included in ArcGIS Desktop running at the ArcInfo license level. Most of the tools require a license for the ArcGIS Spatial Analyst extension. ArcGIS is a commercial GIS software system produced by ESRI, Inc. (http://www.esri.com). The NAWQA Area-Characterization Toolbox is not supported by ESRI, Inc. or its technical support staff. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Open-File Report↗
USGS2011

Analysis of change in marsh types of coastal Louisiana, 1978-2001

Scientists and geographers have provided multiple datasets and maps to document temporal changes in vegetation types and land-water relationships in coastal Louisiana. Although these maps provide useful historical information, technological limitations prevented these and other mapping efforts from providing sufficiently detailed calculations of areal changes and shifts in habitat coverage. The current analysis of habitat change draws upon these past mapping efforts but is based on an advanced, geographic information system dataset that was created by using Landsat 5 Thematic Mapper imagery and digital orthophoto quarter quadrangles. The objective of building this dataset was to more specifically define land-water relationships over time in coastal Louisiana, and it provides the most detailed analysis of vegetation shifts to date. In the current study, we have attempted to explain these vegetation shifts by interpreting them in the context of rainfall records, data from the Palmer Drought Severity Index, and salinity data. During the 23 years we analyzed, total marsh acreage decreased, with conversion of marsh to open water. Furthermore, the general trend across coastal Louisiana was a shift to increasingly fresh marsh types. Although fresh marsh remained almost the same during the 1978-88 study period, there were greater increases during the 1988-2001 study periods. Intermediate marsh followed the same pattern, whereas brackish marsh showed a reverse (decreasing) pattern. Changes in saline (saltwater) marsh were minimal. Interpreting shifts in marsh vegetation types by using climate and salinity data provides better understanding of factors influencing these changes and, therefore, can improve our ability to make predictions about future marsh loss related to vegetation changes. Results of our study indicate that precipitation fluctuations prior to vegetation surveys impacted salinities differently across the coast. For example, a wet 6 months prior to the survey may or may not have made up for a dry period during the earlier 12 months. More research is needed to better understand rainfall periods and how they affect salinity changes. The ability to understand past dynamics and to anticipate future trends in vegetation change and related land loss in the coastal region of Louisiana is a vital part of ongoing and future efforts to conserve its critical wetland ecosystem. With the loss of marsh and resultant changes in hydrology, it is likely that changes in marsh type may show greater variation in the future, even if given only minor changes in precipitation levels.

Open-File Report↗
USGS2011

Combined multibeam and LIDAR bathymetry data from eastern Long Island Sound and westernmost Block Island Sound-A regional perspective

Detailed bathymetric maps of the sea floor in Long Island Sound are of great interest to the Connecticut and New York research and management communities because of this estuary's ecological, recreational, and commercial importance. The completed, geologically interpreted digital terrain models (DTMs), ranging in area from 12 to 293 square kilometers, provide important benthic environmental information, yet many applications require a geographically broader perspective. For example, individual surveys are of limited use for the planning and construction of cross-sound infrastructure, such as cables and pipelines, or for the testing of regional circulation models. To address this need, we integrated 12 multibeam and 2 LIDAR (Light Detection and Ranging) contiguous bathymetric DTMs, produced by the National Oceanic and Atmospheric Administration during charting operations, into one dataset that covers much of eastern Long Island Sound and extends into westernmost Block Island Sound. The new dataset is adjusted to mean lower low water, is gridded to 4-meter resolution, and is provided in UTM Zone 18 NAD83 and geographic WGS84 projections. This resolution is adequate for sea floor-feature and process interpretation but is small enough to be queried and manipulated with standard Geographic Information System programs and to allow for future growth. Natural features visible in the grid include exposed bedrock outcrops, boulder lag deposits of submerged moraines, sand-wave fields, and scour depressions that reflect the strength of the oscillating and asymmetric tidal currents. Bedform asymmetry allows interpretations of net sediment transport. Anthropogenic artifacts visible in the bathymetric data include a dredged channel, shipwrecks, dredge spoils, mooring anchors, prop-scour depressions, buried cables, and bridge footings. Together the merged data reveal a larger, more continuous perspective of bathymetric topography than previously available, providing a fundamental framework for research and resource management activities in this major east-coast estuary.

Open-File Report↗
USGS2011

Relative abundance and distribution of fishes and crayfish at Ash Meadows National Wildlife Refuge, Nye County, Nevada, 2007-08

This study provides baseline data of native and non-native fish populations in Ash Meadows National Wildlife Refuge (NWR), Nye County, Nevada, that can serve as a gauge in native fish enhancement efforts. In support of Carson Slough restoration, comprehensive surveys of Ash Meadows NWR fishes were conducted seasonally from fall 2007 through summer 2008. A total of 853 sampling stations were created using Geographic Information Systems and National Agricultural Imagery Program. In four seasons of sampling, Amargosa pupfish (genus Cyprinodon) was captured at 388 of 659 stations. The number of captured Amargosa pupfish ranged from 5,815 (winter 2008) to 8,346 (summer 2008). The greatest success in capturing Amargosa pupfish was in warm water spring-pools with temperature greater than 25 degrees C, headwaters of warm water spring systems, and shallow (depths less than 10 centimeters) grassy marshes. In four seasons of sampling, Ash Meadows speckled dace (Rhinichthys osculus nevadesis) was captured at 96 of 659 stations. The number of captured Ash Meadows speckled dace ranged from 1,009 (summer 2008) to 1,552 (winter 2008). The greatest success in capturing Ash Meadows speckled dace was in cool water spring-pools with temperature less than 20 degrees C and in the high flowing water outflows. Among 659 sampling stations within the range of Amargosa pupfish, red swamp crayfish (Procambarus clarkii) was collected at 458 stations, western mosquitofish (Gambusia affinis) at 374 stations, and sailfin molly (Poecilia latipinna) at 128 stations. School Springs was restored during the course of this study. Prior to restoration of School Springs, maximum Warm Springs Amargosa pupfish (Cyprinodon nevadensis pectoralis) captured from the six springs of the Warm Springs Complex was 765 (fall 2007). In four seasons of sampling, Warm Springs Amargosa pupfish were captured at 85 of 177 stations. The greatest success in capturing Warm Springs Amargosa pupfish when co-occurring with red swamp crayfish and western mosquitofish was in water with temperature greater than 26 degrees C near the springhead, and in shallow (depths less than 10 centimeters) grassy marshes. Among 177 sampling stations within the range of Warm Springs Amargosa pupfish, red swamp crayfish were collected at 96 stations and western mosquitofish were collected at 49 stations. Removal of convict cichlid (Amatitlania nigrofasciata) from Fairbanks Spring was followed by a substantial increase in Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) captures from 910 pre-removal to 3,056 post-removal. Red swamp crayfish was continually removed from Bradford 1 Spring, which seemed to cause an increase in the speckled dace population. Restoration of Kings Pool and Jackrabbit Springs promoted the success of native fishes with the greatest densities in restored reaches. Ongoing restoration of Carson Slough and its tributaries, as well as control and elimination of invasive species, is expected to increase abundance and distribution of Ash Meadows' native fish populations. Further analysis of data from this study will help determine the habitat characteristic(s) that promote native species and curtail non-native species.

Open-File Report↗
USGS2011

Predicting spread of invasive exotic plants into dewatered reservoirs after dam removal on the Elwha River, Olympic National Park, Washington

The National Park Service is planning to start the restoration of the Elwha River ecosystem in Olympic National Park by removing two high head dams beginning in 2011. The potential for dispersal of exotic plants into dewatered reservoirs following dam removal, which would inhibit restoration of native vegetation, is of great concern. We focused on predicting long-distance dispersal of invasive exotic plants rather than diffusive spread because local sources of invasive species have been surveyed. We included the long-distance dispersal vectors: wind, water, birds, beavers, ungulates, and users of roads and trails. Using information about the current distribution of invasive species from two surveys, various geographic information system techniques and models, and statistical methods, we identified high-priority areas for Park staff to treat prior to dam removal, and areas of the dewatered reservoirs at risk after dam removal.

Washington↗