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At least 721 records · Page 40Linked to original sources

Source pulse enhancement by deconvolution of an empirical Green's function

Observations of the earthquake source-time function are enhanced if path, recording-site, and instrument complexities can be removed from seismograms. Assuming that a small earthquake has a simple source, its seismogram can be treated as an empirical Green's function and deconvolved from the seismogram of a larger and/or more complex earthquake by spectral division. When the deconvolution is well posed, the quotient spectrum represents the apparent source-time function of the larger event. This study shows that with high-quality locally recorded earthquake data it is feasible to Fourier transform the quotient and obtain a useful result in the time domain. In practice, the deconvolution can be stabilized by one of several simple techniques. In this paper, the method is implemented and tested on high-quality digital recordings of aftershocks of the Jan. 9, 1982 Miramichi (New Brunswick) earthquake. In particular, seismograms from a Jan. 17 aftershock (017 13:33 GMT, local mag.=3.5) exhibit path or site effects which complicate the determination of source parameters. After deconvolution, the apparent far-field source of this event is a simple pulse in displacement with duration ≈ 0.07 second for both P and S.

Geophysical Research Letters↗

Automated location correction and spot height generation for named summits in the coterminous United States

Spot elevations published on historical U.S. Geological Survey topographic maps were established as needed to enhance information imparted by the quadrangle’s contours. In addition to other features, labels were routinely placed on mountain summits. While some elevations were established through field survey triangulation, many were computed during photogrammetric stereo-compilation. Today, Global Navigation Satellite System (GNSS) receivers have replaced expensive triangulation methods. However, since GNSS measurements require visiting the feature location, a national dataset containing high-accuracy spot elevations has not yet been created. Consequently, modern U.S. Topo maps are devoid of mountain peak or other spot elevations. Still, topographic map users continue to demand the display of spot heights. Therefore, a pilot study was conducted to evaluate the feasibility of automatically generating elevation values at named U.S. summits using available elevation data. The devised method uses an uphill stepping technique to find the most likely highest point in subsequently higher-resolution elevation models. Resulting elevation values are compared to other published sources. Results from 196 summits indicate that values derived from lidar are generally higher, whereas those populated from the one-third arc-second USGS Seamless 3DEP elevation dataset are generally lower. A thorough understanding of these relationships require the evaluation of more points.

International Journal of Digital Earth↗

ASTER preflight and inflight calibration and the validation of level 2 products

Describes the preflight and inflight calibration approaches used for the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). The system is a multispectral, high-spatial resolution sensor on the Earth Observing System's EOS-AM1 platform. Preflight calibration of ASTER uses well-characterized sources to provide calibration and preflight round-robin exercises to understand biases between the calibration sources of ASTER and other EOS sensors. These round-robins rely on well-characterized, ultra-stable radiometers. An experiment field in Yokohama, Japan, showed that the output from the source used for the visible and near-infrared (VNIR) subsystem of ASTER may be underestimated by 1.5%, but this is still within the 4% specification for the absolute, radiometric calibration of these bands. Inflight calibration will rely on vicarious techniques and onboard blackbodies and lamps. Vicarious techniques include ground-reference methods using desert and water sites. A recent joint field campaign gives confidence that these methods currently provide absolute calibration to better than 5%, and indications are that uncertainties less than the required 4% should be achievable at launch. The EOS-AM1 platform will also provide a spacecraft maneuver that will allow ASTER to see the Moon, allowing further characterization of the sensor. A method for combining the results of these independent calibration results is presented. The paper also describes the plans for validating the Level 2 data products from ASTER. These plans rely heavily upon field campaigns using methods similar to those used for the ground-reference, vicarious calibration methods.

IEEE Transactions on Geoscience and Remote Sensing↗

Sharpening advanced land imager multispectral data using a sensor model

The Advanced Land Imager (ALI) instrument on NASA's Earth Observing One (EO-1) satellite provides for nine spectral bands at 30m ground sample distance (GSD) and a 10m GSD panchromatic band. This report describes an image sharpening technique where the higher spatial resolution information of the panchromatic band is used to increase the spatial resolution of ALI multispectral (MS) data. To preserve the spectral characteristics, this technique combines reported deconvolution deblurring methods for the MS data with highpass filter-based fusion methods for the Pan data. The deblurring process uses the point spread function (PSF) model of the ALI sensor. Information includes calculation of the PSF from pre-launch calibration data. Performance was evaluated using simulated ALI MS data generated by degrading the spatial resolution of high resolution IKONOS satellite MS data. A quantitative measure of performance was the error between sharpened MS data and high resolution reference. This report also compares performance with that of a reported method that includes PSF information. Preliminary results indicate improved sharpening with the method reported here.

Conference Paper↗

Grand Canyon landslide-dam and paleolake triggered by the Meteor Crater impact at 56 ka

This paper hypothesizes that the Meteor Crater impact in Arizona, USA, 56,000 years ago triggered landslides in Grand Canyon that dammed the Colorado River and formed Nankoweap paleolake. This is compatible with shock and earthquake physics for the impact that infer a M5.4 seismic event, attenuated to an effective magnitude of M3.5 at Grand Canyon. Results that support the hypothesis include radiocarbon dating of driftwood and luminescence dating of associated slack-water lake sediments that are preserved in caves up to 60 m above the modern Colorado River. Radiocarbon ages from two locations, including Stanton’s Cave, date the driftwood as 55.25 ± 2.44 ka (n = 4). Sediments associated with the driftwood gave a luminescence age of 56.00 ± 6.39 ka (n = 2). These six Grand Canyon dates, and three published ages for the Meteor Crater impact, show statistically indistinguishable results that support the hypothesis for a geologically instantaneous series of events with a mean age of 55.60 ± 1.30 ka. This work highlights the value of radiocarbon dating near the limits of the technique, integration of multiple dating methods, and seismic and landslide hazards associated with meteorite impacts in regions of extreme topography like Grand Canyon.

Arizona↗

Habitat suitability index curves for paddlefish, developed by the delphi technique

A Delphi exercise conducted with a panel of 11 experts on paddlefish (Polyodon spathula) and an evaluator resulted in 14 riverine habitat suitability index curves associating various life stages or activities of paddlefish with four variables: velocity, depth, substrate type, and temperature. The panel reached a consensus on six of the curves and eight to 10 panelists agreed on the others. Several panelists reported that they found the Delphi exercise to be a good learning experience, and they believed the technique is an appropriate interim method for developing suitability index curves when available data are inadequate for more conventional statistical analyses. Documentation of good paddlefish spawning habitat was the data need most commonly identified by the panelists.

North American Journal of Fisheries Management↗

Aeromagnetic investigations of hazardous waste sites

Aeromagnetic survey data collected by helicopter over hazardous waste sites can be used to map the distribution of buried metallic (ferrous) objects at these sites, including drums and scrap metal. Thorough knowledge of the locations and nature of hazardous waste containers and contaminated objects is needed prior to the start of remediation efforts. Non-invasive geophysical techniques such as the aeromagnetic method provide the best way to obtain this knowledge. The U.S. Geological Survey (USGS) not only has experience in processing and interpreting aeromagnetic surveys of this type but also offers aid in the design and monitoring of contracts for such surveys.

Fact Sheet↗

Velocity and stage data collected in a laboratory flume for water-surface slope determination using a pipe manometer

U.S. Geological Survey (USGS) hydrologists and ecologist are conducting studies to quantify vegetative flow resistance in order to improve numerical models of surface-water flow in the Florida Everglades. Water-surface slope is perhaps the most difficult of the flow resistance parameters to measure in the Everglades due to the very low gradients of the topography and flow. In an effort to measure these very small slopes, a unique pipe manometer was developed for the local measurement of water-surface slopes on the order of 1 centimeter per kilometer (cm/km). According to theory, a very precise measurement of centerline velocity obtained inside the pipe manometer should serve as a unique proxy for water-surface slope in the direction of the pipe axis. In order to confirm this theoretical relationship and calibrate the pipe manometer, water-surface elevation and pipe centerline velocity data were simultaneously measured in a set of experiments carried out in the tilting flume at the USGS Hydraulic Laboratory Facility at Stennis Space Center, Mississippi. A description of the instrumentation and methods used to evaluate this technique for measuring water-surface slope as well as a summary of the entire data set is presented.

Open-File Report↗

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↗

Statistical analyses of data on stream sediments, panned heavy-mineral concentrates, rocks, and waters of the Pusch Ridge Wilderness Area, Arizona

The U.S. Geological Survey and the U.S. Bureau of Mines have conducted a mineral-resource assessment of the Pusch Ridge Wilderness Area, in Pima County near Tucson Arizona. The study consisted of coordinated geological, geochemical, and mineral resource studies with the objective of evaluating the potential for mineral deposits in the 200 km area. The geochemical survey consisted of the collection of stream-sediment samples, stream-sediment samples taken for panning to produce heavy-mineral concentrates, and rock and water samples. The samples were analyzed by both wet chemical and semiquantita-tive emission spectrographic techniques. The sampling procedures, and methods of sample preparation and analysis were reported by Hinkle and others (1981).

Arizona↗

Water-quality, streamflow, and meteorological data for the Tualatin River Basin, Oregon, 1991-93

Surface-water-quality data, ground-water-quality data, streamflow data, field measurements, aquatic-biology data, meteorological data, and quality-assurance data were collected in the Tualatin River Basin from 1991 to 1993 by the U.S. Geological Survey (USGS) and the Unified Sewerage Agency of Washington County, Oregon (USA). The data from that study, which are part of this report, are presented in American Standard Code for Information Interchange (ASCII) format in subject-specific data files on a Compact Disk-Read Only Memory (CD-ROM). The text of this report describes the objectives of the study, the location of sampling sites, sample-collection and processing techniques, equipment used, laboratory analytical methods, and quality-assurance procedures. The data files on CD-ROM contain the analytical results of water samples collected in the Tualatin River Basin, streamflow measurements of the main-stem Tualatin River and its major tributaries, flow data from the USA wastewater-treatment plants, flow data from stations that divert water from the main-stem Tualatin River, aquatic-biology data, and meteorological data from the Tualatin Valley Irrigation District (TVID) Agrimet Weather Station located in Verboort, Oregon. Specific information regarding the contents of each data file is given in the text. The data files use a series of letter codes that distinguish each line of data. These codes are defined in data tables accompanying the text. Presenting data on CD-ROM offers several advantages: (1) the data can be accessed easily and manipulated by computers, (2) the data can be distributed readily over computer networks, and (3) the data may be more easily transported and stored than a large printed report. These data have been used by the USGS to (1) identify the sources, transport, and fate of nutrients in the Tualatin River Basin, (2) quantify relations among nutrient loads, algal growth, low dissolved-oxygen concentrations, and high pH, and (3) develop and calibrate a water- quality model that allows managers to test options for alleviating water-quality problems.

Oregon↗

Assessment of Areal Recharge to the Spokane Valley-Rathdrum Prairie Aquifer, Spokane County, Washington, and Bonner and Kootenai Counties, Idaho

A numerical flow model of the Spokane Valley-Rathdrum Prairie aquifer currently (2007) being developed requires the input of values for areally-distributed recharge, a parameter that is often the most uncertain component of water budgets and ground-water flow models because it is virtually impossible to measure over large areas. Data from six active weather stations in and near the study area were used in four recharge-calculation techniques or approaches; the Langbein method, in which recharge is estimated on the basis of empirical data from other basins; a method developed by the U.S. Department of Agriculture (USDA), in which crop consumptive use and effective precipitation are first calculated and then subtracted from actual precipitation to yield an estimate of recharge; an approach developed as part of the Eastern Snake Plain Aquifer Model (ESPAM) Enhancement Project in which recharge is calculated on the basis of precipitation-recharge relations from other basins; and an approach in which reference evapotranspiration is calculated by the Food and Agriculture Organization (FAO) Penman-Monteith equation, crop consumptive use is determined (using a single or dual coefficient approach), and recharge is calculated. Annual recharge calculated by the Langbein method for the six weather stations was 4 percent of annual mean precipitation, yielding the lowest values of the methods discussed in this report, however, the Langbein method can be only applied to annual time periods. Mean monthly recharge calculated by the USDA method ranged from 53 to 73 percent of mean monthly precipitation. Mean annual recharge ranged from 64 to 69 percent of mean annual precipitation. Separate mean monthly recharge calculations were made with the ESPAM method using initial input parameters to represent thin-soil, thick-soil, and lava-rock conditions. The lava-rock parameters yielded the highest recharge values and the thick-soil parameters the lowest. For thin-soil parameters, calculated monthly recharge ranged from 10 to 29 percent of mean monthly precipitation and annual recharge ranged from 16 to 23 percent of mean annual precipitation. For thick-soil parameters, calculated monthly recharge ranged from 1 to 5 percent of mean monthly precipitation and mean annual recharge ranged from 2 to 4 percent of mean annual precipitation. For lava-rock parameters, calculated mean monthly recharge ranged from 37 to 57 percent of mean monthly precipitation and mean annual recharge ranged from 45 to 52 percent of mean annual precipitation. Single-coefficient (crop coefficient) FAO Penman-Monteith mean monthly recharge values were calculated for Spokane Weather Service Office (WSO) Airport, the only station for which the necessary meteorological data were available. Grass-referenced values of mean monthly recharge ranged from 0 to 81 percent of mean monthly precipitation and mean annual recharge was 21 percent of mean annual precipitation; alfalfa-referenced values of mean monthly recharge ranged from 0 to 85 percent of mean monthly precipitation and mean annual recharge was 24 percent of mean annual precipitation. Single-coefficient FAO Penman-Monteith calculations yielded a mean monthly recharge of zero during the eight warmest and driest months of the year (March-October). In order to refine the mean monthly recharge estimates, dual-coefficient (basal crop and soil evaporation coefficients) FAO Penman-Monteith dual-crop evapotranspiration and deep-percolation calculations were applied to daily values from the Spokane WSO Airport for January 1990 through December 2005. The resultant monthly totals display a temporal variability that is absent from the mean monthly values and demonstrate that the daily amount and timing of precipitation dramatically affect calculated recharge. The dual-coefficient FAO Penman-Monteith calculations were made for the remaining five stations using wind-speed values for Spokane WSO Airport and other assumptions regarding

Scientific Investigations Report↗

A Key to the Pupal Exuviae of the Midges (Diptera: Chironomidae) of Everglades National Park, Florida

A key has been developed for identifying the pupal exuviae of 132 taxa of chironomid midges collected in Everglades National Park, as well as 18 additional species from freshwater habitats adjacent to the Park. Descriptions and illustrations are based upon voucher specimens from extensive collections of chironomid pupal exuviae for faunal surveys and biomonitoring research conducted in ENP and surrounding freshwater areas from 1998 to 2007. The key includes taxonomic comments for confirming identifications, as well as brief summaries of the distribution and ecology of each species in southern Florida waters. Information is also provided on the morphology of chironomid pupal exuviae, recommended references for identifying pupal exuviae, techniques for making slides, and methods to confirm proper identification.

Scientific Investigations Report↗

Deep aquifer recharge in the Columbia River Basalt Group, upper Umatilla River Basin, northeastern Oregon

Groundwater is an important component of the water resources of the upper Umatilla River Basin of northeastern Oregon. As such, understanding the capacity of the resource is vital. Past studies have estimated recharge in the study area. One recent study of the upper Umatilla River Basin indicated that about 80 percent of recharge entering the groundwater system is discharged to streams in the study area through shallow groundwater-flow paths, leaving about 20 percent of recharge to infiltrate deeper parts of the aquifer system. The purpose of this work is to quantify the spatial distribution and variability of deep aquifer recharge in the study area and to understand the reasons for a relatively low percentage of total recharge reaching the deeper parts of the groundwater-flow system. The study area is divided into two distinct physiographic regions—the highly dissected Blue Mountains and the lowland plains. Underlying both regions of the study area are basalts of the Columbia River Basalt Group (CRBG), which is the principal aquifer in the study area. Deep incision by streams in the Blue Mountains disrupts the lateral continuity of the CRBG aquifer units, and infiltrating water is more readily diverted laterally and discharged to streams and springs. In the lowland plains, incision is less pronounced. The shallow CRBG units might be disrupted, but deeper aquifer units retain their lateral continuity and enable groundwater to infiltrate deeper and flow laterally farther downgradient before discharging. Recharge to the deep basalt aquifers is estimated as the difference between total recharge and base flow. Total recharge is the portion of precipitation and applied irrigation water that infiltrates past the root zone to become groundwater recharge. Of this total recharge, a proportion discharges to springs and streams in the study area, and the remaining water infiltrates below the base level of streams and recharges the deep basalt aquifers and contributes to the regional groundwater flow system. The portion of total recharge that recharges the regional flow system is referred to as deep aquifer recharge. Total recharge is the portion of precipitation and applied irrigation water that infiltrates past the root zone to become groundwater recharge. It is the sum of recharge from precipitation and recharge from infiltration of irrigation water. Recharge from precipitation was calculated using a regression method developed for the Columbia Plateau. Recharge from infiltrating irrigation water was obtained from a water balance model developed for the Columbia Plateau. Base flow, the component of streamflow that represents groundwater discharge as opposed to runoff from the land surface, was estimated using the Base Flow Index Modified (BFI-Modified) method, an empirical hydrograph separation technique. Base flow was estimated in eight subbasins with streamgages within the study area. Five of the eight subbasins in which base flow was estimated had permitted water rights for irrigation that specified surface water as the primary source of water. Maximum surface-water withdrawal for irrigation was estimated for all subbasins in which water rights for irrigation occur. The base-flow estimate from BFI-Modified is assumed to be the minimum amount of base flow. The sum of the BFIModified base-flow estimate and the maximum permitted surface-water withdrawal estimate for each subbasin is assumed to be the maximum amount of base flow at the streamgage. These minimum and maximum estimates of base flow were used to calculate minimum and maximum values of deep aquifer recharge in each subbasin analyzed within the study area. Subbasin estimates were scaled up to the Blue Mountains and lowland plains regions, and to the entire study area. Mean annual total recharge for 1981–2010 in the subbasins, analyzed as part of this work, ranged from 6 inches (in.) in the Patawa and Wildhorse Creek subbasins in the lowland plains to as much as 20 in. in the Umatilla River above Meacham Creek subbasin. Mean annual total recharge totaled 4 in. in the lowland plains region and 14 in. in the Blue Mountains. Mean annual total recharge for the entire study area was 11 in. Mean annual base flow ranged from 1 in. in the Patawa and Wildhorse Creek subbasins in the lowland plains to as much as 14 in. in the Umatilla River above Meacham Creek subbasin in the Blue Mountains. Mean annual deep aquifer recharge ranged from 4 in. in the Patawa and Wildhorse Creek subbasins in the lowland plains to as much as 8 in. in the Isqu’ulktpe Creek subbasin in the Blue Mountains. Deep aquifer recharge was 3–4 in. in the lowland plains region and 6 in. in the Blue Mountains. Over the entire study area, mean annual deep aquifer recharge was 5 in. Most groundwater recharge (both total and deep aquifer) in the study area occurred in the Blue Mountains, which highlights the importance of the Blue Mountains as the principal source of groundwater for the study area and for aquifers farther downgradient. Total recharge in the Blue Mountains region represents 86 percent of the mean annual total recharge in the study area in an area that encompasses 65 percent of the study area. However, only 43–44 percent of the mean annual total recharge remains in the system to recharge the deeper, regional aquifer system because the rest is discharged as base flow within the Blue Mountains region. Within the lowland plains region of the study area, an estimated 67–84 percent of the mean annual total recharge remains in the system to recharge the deep, regional aquifer system. Although total recharge in the study area represents only 14 percent of the total recharge across the study area, it contributes 20–24 percent of the water to the deep aquifer. The difference in the percentage of deep groundwater recharge in the Blue Mountains and the lowland plains is attributed to differences in the degree of stream incision. Stream channels are more incised in the Blue Mountains region than they are in the lowland plains. The dissection of the landscape in the Blue Mountains disrupts the lateral continuity of the CRBG aquifer units and allows groundwater to discharge to springs and streams rather than infiltrate more deeply. In the lowland plains region, incision is much less pronounced and deeper CRBG units likely retain their lateral continuity, enabling groundwater to infiltrate more deeply than in the Blue Mountains.

Oregon↗

Correlating sea lamprey density with environmental DNA detections in the lab

Invasive sea lamprey (Petromyzon marinus Linnaeus, 1758) are currently managed by the Great Lakes Fishery Commission in an effort to reduce pest populations below levels that cause ecological damage. One technique to improve stream population assessments could be molecular surveillance in the form of environmental DNA (eDNA) monitoring. We developed and validated four probe-based quantitative polymerase chain reaction (qPCR) assays, then used two probes (cytb, nd1) to determine whether eDNA concentration was correlated with adult and larval sea lamprey density in the lab. We found a strong positive correlation between adult sea lamprey densities of 2, 20, and 200 individuals/2000L and eDNA concentrations in tanks using both assays (cytb, nd1). For larval laboratory tank density trials, eDNA concentrations were generally near our limit of quantification and there was no significant difference in copy numbers detected between larval sea lamprey densities of 1, 5, and 25 individuals/28L. Therefore, we examined detection probability rather than concentration with laboratory tank densities. We observed a trend of increasing detection probabilities with increased larval sea lamprey density that approached significance suggesting that when DNA copy numbers are low, detection rates may be more informative in predicting varying densities of larval sea lamprey. The ability to assess sea lamprey densities from a water sample could be a powerful tool to improve traditional assessment and stream ranking techniques. Further refinement of this method in the field may make eDNA surveillance of sea lamprey a reliable part of stream assessments. Rapid eDNA analysis from many streams may help focus traditional assessment efforts, thereby improving the efficiency of invasive sea lamprey control efforts.

Management of Biological Invasions↗

Catfish science: Status and trends in the 21st century

Catfish science, the study of the fish order Siluriformes, is a diverse and expanding field in terms of advances and breadth of topics. We compiled literature from primary fisheries journals as an index of interest and advances in catfish science to examine temporal trends in the field. The number of catfish scientific publications varied over the past century with strong peaks during 1975–1979 and 2005–2010, which may be the result of interactive scientific and societal influences. Catfish biology was the predominant publication topic until the late 1990s, when ecology, techniques, and management publications became more prevalent. Articles on catfish ecology were most numerous in both the first and second international catfish symposia, but publications on techniques and conservation were more numerous in the second catfish symposium than the first. We summarize the state of knowledge, recent advances, and areas for future attention among topics in catfish science, including sampling and aging techniques, population dynamics, ecology, fisheries management, species diversity, nonnative catfish, and human dimensions, with an emphasis on the gains in this second symposium. Areas that we expect to be pursued in the future are development of new techniques and validation of existing methods; expansion of research to less-studied catfish species; broadening temporal, spatial, and organizational scales; interdisciplinary approaches; and research on societal views and constituent demands. Meeting these challenges will require scientists to span beyond their professional comfort zones to effectively reach higher standards. We look forward to the coming decade and the many advances in the conservation, ecology, and management of catfish that will be shared.

Conference Paper↗

Skin and fin diseases

Fish are critically important to the welfare of this planet and its occupants, the health of both wild and captive fish populations paramount to our survival. This book presents the gross pathology of the most commonly encountered diseases and syndromes of fish in an organ system-based approach. It provides an overview of the diseases and disorders of tropical, ornamental, bait and food fish from freshwater, brackish and marine environments. Readers will gain a broader understanding of the basic biology of infectious and non-infectious diseases in fish, as well as novel diagnostic techniques and innovative disease control methods.

Book chapter↗

Advancements in analytical approaches improve whitebark pine monitoring results

Long-term monitoring programs track the status and trends of species in increasingly vulnerable environments. These monitoring results provide critical information for evaluating, understanding, and managing natural resources. To accurately interpret if and how conditions may be changing for select ecological indicators, it is essential that monitoring programs adopt methods to ensure exceptional data quality. To do this and remain relevant, practitioners need to be flexible and willing to embrace a degree of adaptivity in their protocols. They must periodically re-evaluate their statistical methods and field data collection techniques to provide contemporary, significant, and applicable inferences.

Idaho, Montana, Wyoming↗