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Full-Text Articles in Physical Sciences and Mathematics

Vascular Flora And Vegetation Of Capitol Reef National Park, Utah, Kenneth D. Heil, J. Mark Porter, Rich Fleming, William H. Romme Jan 1993

Vascular Flora And Vegetation Of Capitol Reef National Park, Utah, Kenneth D. Heil, J. Mark Porter, Rich Fleming, William H. Romme

Elusive Documents

No abstract provided.

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Preserves At Risk: An Investigation Of Resource Management Strategies, Implications And Opportunities, R. J. Lilieholm Jan 1993

Preserves At Risk: An Investigation Of Resource Management Strategies, Implications And Opportunities, R. J. Lilieholm

Elusive Documents

Human activities already threaten the globe's physical and biological systems. Worldwide, species extinction rates are estimated to be one thousand times what they would be in the absence of human activity (Wilson 1988). Raven (1988) estimates that 25% of the world's plant and animal species existing in 1985 may be extinct by 2015, with most extinctions occurring in tropical regions. While these extinction rates are staggering, global warming would greatly accelerate extinction rates that some scientists believe may already exceed those accompanying the decline of the dinosaurs 65 million years ago (Wolf 1987).

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An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh Jan 1993

An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

The gastric evacuation rates of brown trout Salmo trutta (0.9–1.6 kg) feeding on fingerling rainbow trout Oncorhynchus mykiss (3.5–7.6 g) were measured in the laboratory at five temperatures (4.5, 9.0, 14.0, 19.0, and 22.5°C). Instantaneous gut evacuation rates (Re) increased exponentially with temperature (T): Re = 0.053se^0.073T, r^2 = 0.98; they varyied from 7%sh^–1 at 4.5°C to 29%sh^–1 at 22.5°C. Linear regressions described the relationship between time and qualitative measures of fish digestion, thus allowing investigators to determine how long an ingested fish would be identifiable at different temperatures. An analysis of published evacuation rates (N = 121) of 22 …

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Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh Jan 1993

Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Historically, thousands of Snake River Sockeye salmon returned to the Sawtooth Valley to spawn. Evermann (1896) reported that the Sawtooth Valley Lakes were teeming with red fish. Bjornn (196~) estimated that 4,360 sockeye returned to Redfish Lake in 1955. These numbers no longer exist. In the 1980's, less than 50 Snake River sockeye salmon survived to spawn (Bowler 1990). Since 19-90, only 13 sockeye have returned. Because of recent declines, the Shoshone-Bannock Tribes (SBT) petitioned the National Marine Fisheries Service (NMFS-) to list Snake River sockeye as endangered. As a result, Snake River sockeye were listed and the Bonneville Power …

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Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh Jan 1993

Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

To determine how moonlight and daylight affect hydroacoustic estimates of fish abundance, we used a dual-beam transducer and echo integration to survey pelagic fish (primarily Bonneville ciscoes Prosopium gemmifer) in Bear Lake, Utah and Idaho. During the new moon, the fish were dispersed (not schooling) below the thermocline, chiefly at the depths of 10–20 m. At full moon, they were dispersed but much closer to the bottom, where they were difficult to detect. Acoustic estimates offish density and biomass during full moons were approximately 50% of values derived during new moons. A diel survey during a new moon indicated that …

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Gravitational Observables And Local Symmetries, Charles G. Torre Jan 1993

Gravitational Observables And Local Symmetries, Charles G. Torre

All Physics Faculty Publications

Using a recent classification of local symmetries of the vacuum Einstein equations, it is shown that there can be no observables for the vacuum gravitational field (in a closed universe) built as spatial integrals of local functions of Cauchy data and their derivatives.

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A First-Principle Derivation Of The High Latitude Total Electron Content Distribution, D. J. Crain, Jan Josef Sojka, Robert W. Schunk, P. H. Doherty, J. A. Klobucher Jan 1993

A First-Principle Derivation Of The High Latitude Total Electron Content Distribution, D. J. Crain, Jan Josef Sojka, Robert W. Schunk, P. H. Doherty, J. A. Klobucher

All Physics Faculty Publications

Calculation of the high-latitude distribution of the vertical total electron content (TEC) is possible using a three-dimensional, time-dependent ionospheric model. Global and local comparisons may be made with observations of TEC. We compare the local diurnal variation of TEC calculated by the model with observations of TEC at Goose Bay, Labrador and Hamilton, Massachusetts. Data from the period of March 1–11, 1989, and monthly averaged data for solar maximum and solar minimum periods are examined. We extend the model to predict diurnal variations of TEC in the polar cap and compare these results with the observed TEC at Thule, Greenland, …

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Symmetries Of The Einstein Equations, Charles G. Torre, Ian M. Anderson Jan 1993

Symmetries Of The Einstein Equations, Charles G. Torre, Ian M. Anderson

All Physics Faculty Publications

We classify all generalized symmetries of the vacuum Einstein equations in four spacetime dimensions. They consist of constant scalings of the metric, and of the infinitesimal action of generalized spacetime diffeomorphisms. Our results rule out a large class of possible ‘‘observables’’ for the gravitational field, and suggest that the vacuum Einstein equations are not integrable.

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Final Environmental Impact Statement To Construct And Operate A Facility To Receive, Store, And Dispose Of 11e.(2) Byproduct Material Near Clive, Utah, United States Nuclear Regulatory Commission Jan 1993

Final Environmental Impact Statement To Construct And Operate A Facility To Receive, Store, And Dispose Of 11e.(2) Byproduct Material Near Clive, Utah, United States Nuclear Regulatory Commission

Final environmental Impact Statements (UT)

A Final Environmental Impact Statement related to the licensing of Envirocare of Utah, Inc.'s proposed disposal facility in Tooele County, Utah, (Docket No. 40-8989) for byproduct material as defined in Section 11e.(2) of the Atomic Energy Act, has been prepared by the Office of Nuclear Material Safety and Safeguards. This statement describes and evaluates (1) the purpose of and need for the proposed action, (2) alternatives considered, and (3) environmental consequences of the proposed action. The Nuclear Regulatory Commission has concluded that the proposed action evaluated under the National Environmental Policy Act of 1969 and 10 CFR Part 51, is …

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Final Environmental Impact Statement North Slope Timber Sale Dixie National Forest Jan 1993

Final Environmental Impact Statement North Slope Timber Sale Dixie National Forest

Final environmental Impact Statements (UT)

This Final Environmental Impact Statement describes the analysis for the proposed North Slope Timber Sale. The 1,730 acre proposal area is located on the north slope of Boulder Mountain within the Teasdale Ranger District (Wayne County, Utah). Alternatives were developed for this proposal which respond to issues identified during the scoping and analysis process.

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Parameterized Study Of The Ionospheric Modification Associated With Sun-Aligned Polar Cap Arcs, D. J. Crain, Jan Josef Sojka, Robert W. Schunk, Lie Zhu Jan 1993

Parameterized Study Of The Ionospheric Modification Associated With Sun-Aligned Polar Cap Arcs, D. J. Crain, Jan Josef Sojka, Robert W. Schunk, Lie Zhu

All Physics Faculty Publications

Sun-aligned (SA) arcs are a prevalent feature of the polar cap ionosphere during northward interplanetary magnetic field conditions. These arcs are, like the auroral arc, a complex electrodynamic system coupling the ionosphere and magnetosphere. The electron precipitation and convection electric field associated with this system modify the polar cap ionospheric plasma distribution. In the past decade, a wealth of observational information has indicated the complexity of these ionospheric modifications, but only a limited number of model studies have been carried out to elucidate the changes associated with SA arcs. In this investigation, an extensive parametric study has been conducted to …

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Modeling Polar Cap F-Region Patches Using Time Varying Convection, Jan Josef Sojka, M. D. Bowline, Robert W. Schunk, D. T. Decker, Cesar E. Valladares, R. Sheehand, D. N. Anders, R. A. Heelis Jan 1993

Modeling Polar Cap F-Region Patches Using Time Varying Convection, Jan Josef Sojka, M. D. Bowline, Robert W. Schunk, D. T. Decker, Cesar E. Valladares, R. Sheehand, D. N. Anders, R. A. Heelis

All Physics Faculty Publications

Creation of polar cap F‐region patches are simulated for the first time using two independent physical models of the high latitude ionosphere. The patch formation is achieved by temporally varying the magnetospheric electric field (ionospheric convection) input to the models. The imposed convection variations are comparable to changes in the convection that result from changes in the By IMF component for southward interplanetary magnetic field (IMF). Solar maximum‐winter simulations show that simple changes in the convection pattern lead to significant changes in the polar cap plasma structuring. Specifically, in winter, as enhanced dayside plasma convects into the polar …

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A Time-Dependent Model Of Polar Cap Arcs, Lie Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain Jan 1993

A Time-Dependent Model Of Polar Cap Arcs, Lie Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain

All Physics Faculty Publications

A two-dimensional time-dependent model of polar cap arcs has been developed. The electrodynamics of the polar cap arcs are treated self-consistently in the frame of the coupled magnetosphere-ionosphere system. The focus of this paper is to introduce the physics and mathematical formulation of the model and describe the features of the spatial structure and temporal evolution of the polar cap arcs. The modeling results indicate that the time constant for the formation of the polar cap arcs is around 10 min. It is found that an initial single-arc precipitation pattern associated with a polar cap arc tends to split into …

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Influence Of Horizontal Inhomogeneity In The Ionosphere On The Reflection Of Alfvén Waves, Lie Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain Jan 1993

Influence Of Horizontal Inhomogeneity In The Ionosphere On The Reflection Of Alfvén Waves, Lie Zhu, Jan Josef Sojka, Robert W. Schunk, D. J. Crain

All Physics Faculty Publications

A study of the reflection of Alfvén waves at a horizontally inhomogeneous ionosphere has been carried out. In this study, the Alfvén speed above the ionosphere is assumed to be uniform and the ionosphere is treated as a height‐integrated conducting slab. Analytical and numerical results indicate that the horizontal nonuniformity of the ionospheric conductivity can lead to a rotation of the reflected wave fields and cause field‐aligned currents that originate in the ionosphere. A strong conductivity nonuniformity in the direction perpendicular to the incident wave field, large Hall to Pedersen conductivity ratios, and low conductivity values lead to a large …

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Femtosecond Thermionic Emission In The Space-Charge Limited Regime, D. Mark Riffe, X. Y. Wang, M. C. Downer, D. L. Fisher, T. Tajima, J. L. Erskine Jan 1993

Femtosecond Thermionic Emission In The Space-Charge Limited Regime, D. Mark Riffe, X. Y. Wang, M. C. Downer, D. L. Fisher, T. Tajima, J. L. Erskine

All Physics Faculty Publications

We study femtosecond-laser-pulse-induced electron emission from W(100), Al(110), and Ag(lll) in the sub-damage regime (1–44 mJ/cm2 fluence) by simultaneously measuring the incident-light reflectivity, total electron yield, and electron-energy distribution curves of the emitted electrons. The total-yield results are compared with a space-charge-limited extension of the Richardson-Dushman equation for short-time-scale thermionic emission and with particle-in-a-cell computer simulations of femtosecond-pulsed-induced thermionic emission. Quantitative agreement between the experimental results and two calculated temperature-dependent yields is obtained and shows that the yield varies linearly with temperature beginning at a threshold electron temperature of ~0.25 eV The particle-in-a-cell simulations also reproduce the experimental electron-energy …

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Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa Jan 1993

Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa

Reports

Executive Summary: Many pathways exist for transportation agencies and other public and private agencies to become responsible for sites contaminated by hazardous wastes. As a reult, agencies frequently face a multitude of lega, regulatory, financial, technical, and health risk problems. When transportation agencies become involved in the remediation of hazardous waste sites, the common practice is to hire consultants and contractors for the clean up process. Because the field of hazardous waste site remediation is changing so rapidly, agency personnel evaluating the consultant's recommendations need to ahve access to the most recent regulatory and remediation information. Early stages of the …

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A Prototype Computer Based Tutorial For The Use Of Highway Patrol Radar Guns, William J. Grenney, Thad E. Senti Jan 1993

A Prototype Computer Based Tutorial For The Use Of Highway Patrol Radar Guns, William J. Grenney, Thad E. Senti

Reports

Executive Summary: The software contained in this package, termed POSAT (Police Officer Standards and Training) is the prototype knowledge-base decision support system developed specifically for the Utah State Police Academy. All police officers must be certified annual for the use of radar guns. This self-study computer program is intended to reduce the cost of providing field training for hundreds of police officers each year. By installing the POSAT software at remote locations, polic officers within a certain districut need only to travel to the nearest remote testing sight to take the exam and renew their radar certification. POSAT automatically transmits …

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Diamond Mountain Resource Area Resource Management Plan And Environmental Impact Statement, United States Bureau Of Land Management Jan 1993

Diamond Mountain Resource Area Resource Management Plan And Environmental Impact Statement, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

This proposed resource management plan and final environmental impact statement addresses management of all resources on approximately 709,000 acres of public land administered by the Bureau of Land Management, Diamond Mountain Resource Area, Vernal District, in Daggett, Duchesne, and portions of Uintah Counties, in northeastern Utah.

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Predicting Regeneration Establishment With The Prognosis Model, United States Department Of Agriculture, Forest Service Jan 1993

Predicting Regeneration Establishment With The Prognosis Model, United States Department Of Agriculture, Forest Service

Forestry

Conifer establishment following regeneration timber harvests is predicted by version 2 of the Regeneration Establishment Model, a submodel of the Prognosis Model. The regeneration model covers 10 species for forests in Montana, central Idaho, and northern Idaho. Most harvest and site preparation methods can be simulated so that alternative treatments can be evaluated. Also included in the model is the influence of western spruce budworm (Choristoneura accidentalis) on regeneration success. The model predicts the probability of stocking, seedling density, species composition, and seedling heights 2 to 20 years after harvest. This paper describes the study design, equation development, model formulation, …

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Snapshot In Time, Repeat Photography On The Boise National Forest 1870-1992, United States Department Of Agriculture Jan 1993

Snapshot In Time, Repeat Photography On The Boise National Forest 1870-1992, United States Department Of Agriculture

Forestry

A forest health crisis of unprecedented proportions faced the Boise National Forest in the early years of the 1990's. Six years of drought set the stage for catastrophic outbreaks of insect and disease in the various tree communities of the forest, and wildfires burned hotter and more frequently than at any time in the past. In our often desperate search for ways to moderate the crisis, we turned to the notion of repeat photography to try to understand what happened in the past and how things are different now. We hoped to find some clues that would help shape management …

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Evaluation Of Roadside Stabilization And Beautification Plantings In South-Central Utah, United States Department Of Agriculture, Forest Service Jan 1993

Evaluation Of Roadside Stabilization And Beautification Plantings In South-Central Utah, United States Department Of Agriculture, Forest Service

Plants

Numerous roadside plantings at semiarid sites in the south-central Utah counties of Juab, Sanpete, and Sevier were intended to stabilize roadsides with plants harmonizing with natural vegetation. The plantings, originally for demonstration, began in the 1950's. They included bareroot transplants and direct seedings. Soils and geologic substrates at six sites were analyzed for 15 characteristics. Plant performance and survival was summarized for 37 sites. Thirty species established well by direct seeding and 62 species established well from transplants. Numerous other species have also persisted at the planting sites but are not as vigorous or as well adapted. Direct seedings were …

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Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service Jan 1993

Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service

Environmental Assessments (NV)

No abstract provided.

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Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service Jan 1993

Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service

Environmental Assessments (NV)

No abstract provided.

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Final Environmental Impact Statement Moyer Salt Timber Sale, United States Forest Service Jan 1993

Final Environmental Impact Statement Moyer Salt Timber Sale, United States Forest Service

Final Environmental Impact Statements (ID)

This Final Environmental Impact Statement documents the analysis of the effects of the proposed timber harvesting and related road construction in the 15,360 acre Moyer Salt Analysis Area. The proposed actions are designed to help achieve the silvicultural goals and objectives of the 1988 Salmon National Forest Land and Resource Management Plan (Forest Plan).

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Probability Of Fire-Stopping Precipitation Events, U.S. Forest Service Jan 1993

Probability Of Fire-Stopping Precipitation Events, U.S. Forest Service

All U.S. Government Documents (Utah Regional Depository)

The possibility that a useful probability for fire stopping precipitation could be developed from historical weather records was investigated.

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Flood Insurance Study, City Of Price, Utah, Carbon County, Federal Emergency Management Agency Jan 1993

Flood Insurance Study, City Of Price, Utah, Carbon County, Federal Emergency Management Agency

All U.S. Government Documents (Utah Regional Depository)

This Flood Insurance Study revises and updates a previous Flood Insurance Study/Flood Insurance Rate Map for the City of Price, Carbon County, Utah. This information will be used by the City of Price to update existing floodplain regulations as part of the Regular Phase of the National Flood Insurance Program (NFIP). The information will also be used by local and regional planners to further promote sound land use and floodplain development.

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Rangeland Monitoring: Analysis, Interpretation, And Evaluation, United States Bureau Of Land Management Jan 1993

Rangeland Monitoring: Analysis, Interpretation, And Evaluation, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

The collection of monitoring data results in quantitative and qualitative information obtained from measurements or estimates of the natural resources. These data are most valuable when their meaning is defined and presented in understandable terms to the resource manager. This is the analysis, interpretation, and evaluation process. The result is the documentation of conclusions on the progress of management to accomplish specific management objectives. Such conclusions are used for management and planning purposes, and in particular, for determining managment actions and establishing new or revised management objectives.

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Overview Of The Proposed Critical Habitat For The Colorado River Endangered Fishes, United States Department Of The Interior Fish And Wildlife Service Jan 1993

Overview Of The Proposed Critical Habitat For The Colorado River Endangered Fishes, United States Department Of The Interior Fish And Wildlife Service

All U.S. Government Documents (Utah Regional Depository)

This document presents an overview of the process, procedures and determinations associated with the proposed critical habitat designation for the razorback sucker, Colorado squawfish, humpback chub, and bonytail (also known as bonytail chub). These species are listed as endangered under the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531 et seq.). Part I is an overview of the proposed critical habitat designation for the Colorado River endangered fishes. Part II is a summary of the biological information used in determining areas for proposed designation and the description of each area proposed on January 29, 1993 (58 FR …

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Archeological Investigations At Two Sites In Dinosaur National Monument: 42un1724 And 5mf2645, United States Department Of The Interior National Park Service Jan 1993

Archeological Investigations At Two Sites In Dinosaur National Monument: 42un1724 And 5mf2645, United States Department Of The Interior National Park Service

All U.S. Government Documents (Utah Regional Depository)

Archeological excavations in Dinosaur National Monument (DINO) were conducted at 5MF2645 (the Pool Creek Site) in 1988 and 42UN1724 (Juniper Ledge Shelter) in 1989. The information from these two sites, along with additional archeological data obtained between 1988 and 1992, have expanded our knowledge of the past 3700 years of human occupation in the DINO area. Juniper Ledge Shelter (42UN1724) is a south-southeast facing rockshelter in the Jones Hole Ely Creek area of the monument. Excavation of a two meter square unit produced evidence of three occupational components and a Fremont burial of an adult female with associated artifacts. The …

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Environmental Assessment, Proposed Predatory Animal Damage Control On Public Lands In Sweetwater, Lincoln, Uinta, And Sublette Counties, Wyoming, United States Department Of The Interior Bureau Of Land Management Jan 1993

Environmental Assessment, Proposed Predatory Animal Damage Control On Public Lands In Sweetwater, Lincoln, Uinta, And Sublette Counties, Wyoming, United States Department Of The Interior Bureau Of Land Management

Environmental Assessments (WY)

This Environmental Assessment is prepared by the Bureau of Land Management (BLM), Rock Springs District with the cooperative participation of the U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Animal Damage Control Unit (USDA-APHIS-ADC, hereafter referred to as APHIS-ADC). This environmental assessment documents the environmental impact analysis of the APHIS-ADC ongoing and proposed program of predatory animal damage control for the protection of domestic livestock and wildlife within the BLM Rock Springs District. The environmental assessment analyzes the impacts associated with the full range of animal damage control activities included in the APHIS-ADC proposed Predatory Animal Damage Control …

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