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At least 253 records · Page 14Linked to original sources
USGS1980

Shallow, low-permeability reservoirs of northern Great Plains: Assessment of their natural gas resources.

Major resources of natural gas are entrapped in low-permeability, low-pressure reservoirs at depths less than 4,000 ft (1,200 m) in the northern Great Plains. This shallow gas is the product of the immature stage of hydrocarbon generation and is referred to as biogenic gas. Prospective low-permeability, gas-bearing reservoirs range in age from late Early to Late Cretaceous and include most of the section from the base of the Mowry Shale to the top of the Judith River Formation. For detailed examination, the potential reservoir section was divided into five intervals represented by one or more formations and their correlatives. The intervals selected correspond to (1) Mowry Shale, (2) Belle Fourche Shale and Greenhorn Formation, (3) Carlile Shale, (4) Niobrara and Telegrap Creek Formations and Eagle Sandstone, and (5) Claggett Shale and Judith River Formation and their equivalents. Within each interval, several different facies are developed. The following facies were identified and mapped for each interval: nonmarine rocks, coastal sandstones, shelf sandstones, siltstones, shales, and chalks. Two types of shelf sandstone were differentiated but generally not mapped separately because of lack of well log control. The "sand ridge" type has reservoir properties comparable to coastal sandstones and occurs as isolated tongues as much as 75 ft (23 m) thick. The second type of shelf sandstone is in beds commonly less than 1 in. (3 cm) thick which are interbedded with shale and contain a high content of allogenic silt- and clay-size material. It is impossible to differentiate these individual beds on conventional well logs. The siltstone and shale facies are grouped to ether because conventional logs cannot distinguish between these two rock types, particularly when they are interbedded. For future evaluation of natural gas resources from low-permeability reservoirs, it will be necessary to differentiate between the siltstone and shale facies and to identify individual beds, particularly very thin ones, within the shelf sandstone facies. Each facies contains distinct reservoir types, some of which are low in permeability. The most promising low-permeability reservoirs are developed in the shelf sandstone, siltstone, and chalk facies. Reservoirs within these facies are particularly attractive because they are enveloped by thick sequences of shale which serve as both a source and a seal for the gas. When naturally fractured, these shales also may be low-productivity gas reservoirs similar to the Devonian shales of the Appalachian basin. In addition, facies with low-permeability reservoirs are present over most of the study area when maps for all of the intervals are combined. Natural gas is produced from low-permeability reservoirs in the northern Great Plains in the southern part of western Canada. Established production covers an area of approximately 8,000 sq mi (20,700 sq km) where reported recoverable reserves average as much as 2 Bcf sq mi. Using these reserve data as an analog, the United States portion may contain resources of natural gas in excess of 100 Tcf. The volume of recoverable gas in the United States will depend on the development of improved recovery technology and higher gas prices relative to costs.

northern Great Plains↗
USGS2013

A framework for quantitative assessment of impacts related to energy and mineral resource development

Natural resource planning at all scales demands methods for assessing the impacts of resource development and use, and in particular it requires standardized methods that yield robust and unbiased results. Building from existing probabilistic methods for assessing the volumes of energy and mineral resources, we provide an algorithm for consistent, reproducible, quantitative assessment of resource development impacts. The approach combines probabilistic input data with Monte Carlo statistical methods to determine probabilistic outputs that convey the uncertainties inherent in the data. For example, one can utilize our algorithm to combine data from a natural gas resource assessment with maps of sage grouse leks and piñon-juniper woodlands in the same area to estimate possible future habitat impacts due to possible future gas development. As another example: one could combine geochemical data and maps of lynx habitat with data from a mineral deposit assessment in the same area to determine possible future mining impacts on water resources and lynx habitat. The approach can be applied to a broad range of positive and negative resource development impacts, such as water quantity or quality, economic benefits, or air quality, limited only by the availability of necessary input data and quantified relationships among geologic resources, development alternatives, and impacts. The framework enables quantitative evaluation of the trade-offs inherent in resource management decision-making, including cumulative impacts, to address societal concerns and policy aspects of resource development.

Natural Resources Research↗
USGS1998

A policy model to initiate environmental negotiations: Three hydropower workshops

How do I get started in natural resource negotiations? Natural resource managers often face difficult negotiations when they implement laws and policies regulating such resources as water, wildlife, wetlands, endangered species, and recreation. As a result of these negotiations, managers must establish rules, grant permits, or create management plans. The Legal‐Institutional Analysis Model (LIAM) was designed to assist managers in systematically analyzing the parties in natural resource negotiations and using that analysis to prepare for bargaining. The LIAM relies on the theory that organizations consistently employ behavioral roles. The model uses those roles to predict likely negotiation behavior. One practical use of the LIAM is when all parties to a negotiation conduct a workshop as a way to open the bargaining on a note of trust and mutual understanding. The process and results of three LIAM workshops designed to guide hydroelectric power licensing negotiations are presented. Our experience with these workshops led us to conclude that the LIAM can be an effective tool to begin a negotiation and that trust built through the workshops can help create a successful result.

Human Dimensions of Wildlife: An International Jou↗
USGS2021

Navigating ecological transformation: Resist-accept-direct as a path to a new resource management paradigm

Natural resource managers worldwide face a growing challenge: Intensifying global change increasingly propels ecosystems toward irreversible ecological transformations. This nonstationarity challenges traditional conservation goals and human well-being. It also confounds a longstanding management paradigm that assumes a future that reflects the past. As once-familiar ecological conditions disappear, managers need a new approach to guide decision-making. The resist–accept–direct (RAD) framework, designed for and by managers, identifies the options managers have for responding and helps them make informed, purposeful, and strategic choices in this context. Moving beyond the diversity and complexity of myriad emerging frameworks, RAD is a simple, flexible, decision-making tool that encompasses the entire decision space for stewarding transforming ecosystems. Through shared application of a common approach, the RAD framework can help the wider natural resource management and research community build the robust, shared habits of mind necessary for a new, twenty-first-century natural resource management paradigm.

BioScience↗
USGS2020

Aligning climate models with stakeholder needs: Advances in communicating future rainfall uncertainties for south Florida decision makers

Changes in future precipitation are of great importance to climate data users in South Florida. A recent U.S. Geological Survey workshop, “Increasing Confidence in Precipitation Projections for Everglades Restoration,” highlighted a gap between standard climate model outputs and the climate information needs of some key Florida natural resource managers. These natural resource managers (hereafter broadly defined as “climate data users”) need more tailored output than is commonly provided by the climate modeling community. This study responds to these user needs by outlining and testing an adaptable methodology to select output from ensemble climate‐model simulations based on user‐defined precipitation drivers, using statistical methods common across scientific disciplines. This methodology is developed to provide a “decision matrix” that guides climate data users to specify the subset of models most important to their work based on each user's season (winter, summer, and annual) and the condition (dry, wet, neutral, and no threshold events) of interest. The decision matrix is intended to better communicate the subset of models best representing precipitation drivers. This information could increase users' confidence in climate models as a resource for natural resource planning and can be used to direct future dynamical downscaling efforts. This methodology is based in dynamical processes controlling precipitation via remote and local teleconnections. We also suggest that future climate studies in South Florida include high‐resolution climate model runs (i.e., ocean eddy resolving) in conjunction with dynamical downscaling to adequately capture precipitation variability.

South Florida↗
USGS2002

Values and attitudes of National Wildlife Refuge managers and biologists; Report to respondents

The issues affecting natural resource management, the society in which natural resource management occurs, natural resource agency personnel, and the publics they serve have changed in recent decades. Previous studies of Refuge professionals in the U.S. Fish and Wildlife Service (Service) have revealed that employees lack strong commitment to the current organizational structure, were frustrated with the lack of communication within the agency and felt there was a need for strong leadership (PEER 1998, 1999). These results prompted the authors to have further questions about refuge management in the Fish and Wildlife Service. What do employees value about their agency? Is there a difference in values between refuge managers and biologists and if so, what are those differences and what influences those differences? Recently, there has been speculation that changes in society and the demographic makeup of natural resource professionals has caused a paradigm shift for natural resource management (Ballard 2002; Brown and Harris 1992abc, 2000; Maestas 2002). But, there has been little work assessing the values, attitudes or behaviors of natural resource professionals to determine if a paradigm shift is really occurring. Most of the work in the field of values, attitudes, and behaviors has focused on the public and their interaction with environmental management issues; such as, endangered species management (Lybecker et al. 2002; Solomon 1998), human-wildlife conflict (Baker and Fritsch 1997; Chase et al. 1999; Jones and Thomas 1999; Mankin et al. 1999), changes in hunting or trapping regulations (Loker et al. 1998; Manfredo et al. 1999; Whittaker and Torres 1998), or management of public lands (Badalamente et al. 2000). The purpose of this study was to gain a better understanding of the values and attitudes refuge employees have toward natural resources. The goal was to survey National Wildlife Refuge professionals about natural resource management. We surveyed Refuge Managers and Refuge Biologists (n=480) at staffed U.S. National Wildlife Refuges in the contiguous 48 states in the fall of 200 1. We used a modified Dillman design, resulting in a 68% response rate. The objectives of this study were to (1) determine and compare the environmental values of refuge managers and biologists at selected refuges and (2) assess attitudes about various institutional factors (public involvement and planning). Analyses of data revealed that these managers and biologists did not differ substantially in terms of their environmental values. Refuge professionals were supportive of public involvement in planning and management, but hoped to maintain management authority throughout the process. Professionals were skeptical concerning the applicability of long term planning, but were generally supportive of the planning process. Attitudes toward the Service were conflicting: professionals felt that the Service needed to provide better leadership and direction, but that the Refuge System needed to assert its autonomy and independence from the rest of the Service.

Open-File Report↗
USGS2008

Base of principal aquifer for the Elkhorn-Loup model area, North-Central Nebraska

In Nebraska, the water managers in the Natural Resources Districts and the Nebraska Department of Natural Resources are concerned with the effect of ground-water withdrawal on the availability of surface water and the long-term effects of ground-water withdrawal on ground- and surface-water resources. In north-central Nebraska, in the Elkhorn and Loup River Basins, ground water is used for irrigation, domestic supply, and public supply; surface water is used in this area for irrigation, recreation, and hydropower production. In recognition of these sometimes competing ground- and surface-water uses in the Elkhorn and Loup River Basins, the U.S. Geological Survey, the Lewis and Clark Natural Resources District, the Lower Elkhorn Natural Resources District, the Lower Loup Natural Resources District, the Lower Niobrara Natural Resources District, the Lower Platte North Natural Resources District, the Middle Niobrara Natural Resources District, the Upper Elkhorn Natural Resources District, and the Upper Loup Natural Resources District agreed to cooperatively study water resources in the Elkhorn and Loup River Basins. The goals of the overall study were to construct and calibrate a regional ground-water flow model of the area and to use that flow model as a tool to assess current and future effects of ground-water irrigation on stream base flow and to help develop long-term water-resource management strategies for this area, hereafter referred to as the Elkhorn-Loup model area. The Elkhorn-Loup model area covers approximately 30,800 square miles, and extends from the Niobrara River in the north to the Platte River in the south. The western boundary of the Elkhorn-Loup model area coincides with the western boundary of the Middle Niobrara, Twin Platte, and Upper Loup Natural Resources Districts; the eastern boundary coincides with the approximate location of the western extent of glacial till in eastern Nebraska. The principal aquifer in most of the Elkhorn-Loup model area is the High Plains aquifer; the principal aquifer in the remaining part of the Elkhorn-Loup model area is an unnamed alluvial aquifer. The upper surface of the geologic units that directly underlie the aquifer is called the 'base of aquifer' in this report. The geologic unit that forms the base of aquifer in the Elkhorn-Loup model area varies by location. The Tertiary-age Brule Formation generally is the base of aquifer in the west; the Cretaceous-age Pierre Shale generally is the base of aquifer in the east. The purpose of this report is to update the altitude and configuration of the base of the principal aquifer in the Elkhorn-Loup model area and a 2-mile buffer area around the Elkhorn-Loup model area, using base-of-aquifer data from test holes, registered water wells, and oil and gas wells within the Elkhorn-Loup model area and a 20-mile buffer area around the Elkhorn-Loup model area that have become available since the publication of earlier maps of the base of aquifer for this area. The base-of-aquifer map is important for the Elkhorn-Loup ground-water flow model because it defines the model's lower boundary. The accuracy of the Elkhorn-Loup ground-water flow model and the accuracy of the model's predictions about the effects of ground-water irrigation on stream base flow are directly related to the accuracy of the model's lower boundary.

Scientific Investigations Map↗
USGS2009

Water Resources and Natural Gas Production from the Marcellus Shale

The Marcellus Shale is a sedimentary rock formation deposited over 350 million years ago in a shallow inland sea located in the eastern United States where the present-day Appalachian Mountains now stand (de Witt and others, 1993). This shale contains significant quantities of natural gas. New developments in drilling technology, along with higher wellhead prices, have made the Marcellus Shale an important natural gas resource. The Marcellus Shale extends from southern New York across Pennsylvania, and into western Maryland, West Virginia, and eastern Ohio (fig. 1). The production of commercial quantities of gas from this shale requires large volumes of water to drill and hydraulically fracture the rock. This water must be recovered from the well and disposed of before the gas can flow. Concerns about the availability of water supplies needed for gas production, and questions about wastewater disposal have been raised by water-resource agencies and citizens throughout the Marcellus Shale gas development region. This Fact Sheet explains the basics of Marcellus Shale gas production, with the intent of helping the reader better understand the framework of the water-resource questions and concerns.

Fact Sheet↗
USGS2023

Comprehensive inventory of habitat assessment and evaluation datasets to support Deepwater Horizon mesophotic and deep benthic communities

This report is part of the NOAA Mesophotic and Deep Benthic Communities (MDBC) Series of publications that share the results of work conducted by the Deepwater Horizon MDBC restoration projects. The 2010 Deepwater Horizon oil spill was an unprecedented event. Approximately 3.2 million barrels of oil were released into the deep ocean over nearly three months. The plume of oil moved throughout the water column, formed surface slicks that cumulatively covered an area the size of Virginia, and washed oil onto at least 1,300 miles of shoreline habitats. More than 770 square miles (2,000 square kilometers) of deep benthic habitat surrounding the Deepwater Horizon wellhead and 4-square miles of the Pinnacles mesophotic reef complex, located at the edge of the continental shelf, were injured by the oil spill. Under the Oil Pollution Act, state and federal natural resource trustees conducted a Natural Resource Damage Assessment (NRDA). The Trustees assessed damages, quantifying the unprecedented injuries to natural resources and lost services. They also developed a programmatic restoration plan to restore injured resources and compensate the public for lost services. In April 2016, a settlement was finalized that included up to $8.8 billion in funding for the Deepwater Horizon Trustees to restore the natural resource injuries caused by the oil spill as described in their programmatic restoration plan, Final Programmatic Damage Assessment and Restoration Plan and Final Programmatic Environmental Impact Statement. The Deepwater Horizon Open Ocean Trustee Implementation Group is responsible for restoring natural resources and their services within the Open Ocean Restoration Area that were injured by the oil spill. The Open Ocean Trustees include NOAA, Department of the Interior, U.S. Environmental Protection Agency, and U.S. Department of Agriculture. In 2019, the Open Ocean Trustee Implementation Group committed more than $126 million to implement four restoration projects to address the injury to MDBC. The MDBC projects are: mapping, Ground-truthing, and Predictive Habitat Modeling; Habitat Assessment and Evaluation; Coral Propagation Technique Development; and Active Management and Protection. NOAA and the Department of the Interior are implementing the projects, in cooperation with a range of partners, over eight years. Together, the projects take a phased approach to meet the challenges involved in restoring deep-sea habitats. Challenges to restoration include a limited scientific understanding of these communities, limited experience with restoration at the depths at which these communities occur, and remote locations that limit accessibility. More information about Deepwater Horizon restoration and the MDBC restoration projects is available at: www.gulfspillrestoration.noaa.gov.

Gulf of Mexico↗
USGS1987

BIA interpretation techniques for vegetation mapping using thematic mapper false color composites (interim report for San Carlos Reservation)

The Bureau of Indian Affairs (BIA) is responsible for the natural resource management of approximately 52 million acres of Trust lands in the contiguous United States. The lands are distributed in a "patchwork" fashion throughout the country. Management responsibilities on these areas include: minerals, range, timber, fish and wildlife, agricultural, cultural, and archaeological resources. In an age of decreasing natural resources and increasing natural resource values, effective multiple resource management is critical. BIA has adopted a "systems approach" to natural resource management which utilizes Geographic Information System (GIS) technology. The GIS encompasses a continuum of spatial and relational data elements, and included functional capabilities such as: data collection, data entry, data base development, data analysis, data base management, display, and report generalization. In support of database development activities, BIA and BLM/TGS conducted a cooperative effort to investigate the potential of 1:100,000 scale Thematic Mapper (TM) False Color Composites (FCCs) for providing vegetation information suitable for input to the GIS and to later be incorporated as a generalized Bureau wide land cover map. Land cover information is critical as the majority of reservations currently have no land cover information in either map or digital form. This poster outlines an approach which includes the manual interpretation of land cover using TM FCCs, the digitizing of interpreted polygons, and the editing of digital data, used upon ground truthing exercises. An efficient and cost-effective methodology for generating large area land cover information is illustrated for the Mineral Strip area on the San Carlos Indian Reservation in Arizona. Techniques which capitalize on the knowledge of the local natural resources professionals, while minimizing machine processing requirements, are suggested.

Arizona↗
USGS1989

Annotated bibliography of economic literature on wetlands

This bibliography is intended for the use of wetlands scientists, policy analysts, and natural resource professionals who have little acquaintance with natural resource economics, and natural resource professionals who have some background in economic analysis and wish to sharpen their appreciation of the specialized methods used to value the nonmarket uses of wetland resources. It is not intended to serve as a first primer of natural resource economics. The purpose of including this discussion is to introduce the reader to the fact that specialized language and analytic techniques are used in this field, and that summary discussion of these techniques are not available in introductory or intermediate level economics textbooks. A key difficulty in economic analysis lies in the need that economists have to express common-sense terms such as "demand" or "supply" in a precise way; this facilitates the interpretation of data and is a powerful aid in making internally consistent, policy analysis. Natural resource economists would like to find a consistent, intuitively plausible measure of the social benefits conferred by some good or service. The most common fallacy noneconomists make in this field is to use expenditures as a measure of well-being or benefits. This measure is defective; expenditures may rise, while benefits fall. The following simple example should clarify the issue. Suppose that a certain population center, in the 1940's, is located 5 miles from a riverine recreation site. Suppose that a factory opens up 15 miles away from the site during the 1950's, and closes at the end of the 1960's; and that during this 20-year period, the bulk of this region's populace resides 15 miles from the site, close to the factory. In the 1970's, the populace of the region returns to the old population center, 5 miles from the recreation site. The benefits conferred by the site diminished during the 1950's and 1960's, even though travel (and even total) expenditures associated with the use of the site may have risen during this period. Both intuition and formal analysis suggest that accurate estimates of benefits conferred by a good or service provide quantitative indices of the availability of good substitutes for the good or service in question., The fewer low-priced substitutes, the greater the benefits conferred by the good. The prices (quantities) of available substitutes may be needed to specify empirically estimated demand (supply) curves. If so, omission of these variables will produce biased estimates of net benefits conferred if the approach used to estimate social benefits is based on the shape and position of an empirically estimated demand (supply) curve. In general, a good grasp of the meaning of both demand and supply (curves) is needed to produce sound estimates of benefits conferred by some commodity. Demand and supply curves are discussed in the following section that deals with various techniques for estimating benefits conferred by outdoor recreation sites. With wetlands functions and resources, the divergence between large total values and very low (zero) marginal values lies behind much of the controversy as to the appropriate procedure for imputing values to wetlands preservation benefits. If some type of wetland habitat is not a limiting factor in the production of some target wildlife species, the marginal value product of that habitat type is zero. The total social marginal product of the wetlands habitat type or complex may be very large, but if the removal of the last unit does not diminish total output, reallocating the land to more valuable economic activities increases social welfare.

Report↗
USGS2006

Natural Bitumen Resources of the United States

Major natural bitumen accumulations in the United States are estimated to contain about 36 billion barrels of measured in-place resource and about 18 billion barrels of speculative in-place resource. Major natural bitumen resources are in Alabama, Alaska, California, Kentucky, New Mexico, Oklahoma, Texas, Utah, and Wyoming.

Fact Sheet↗
USGS2008

Continuous Temperature and Water-Level Data Collected for a Heat Tracer Study on a Selected Reach of Tri-State Canal, Western Nebraska, 2007

The water supply in parts of the North Platte River Basin in the Nebraska Panhandle has been designated as fully appropriated or over appropriated by the Nebraska Department of Natural Resources. Recent legislation (LB 962) requires the North Platte Natural Resources District and the Nebraska Department of Natural Resources to develop an Integrated Management Plan to balance ground- and surface-water supply and demand within the North Platte Natural Resources District. For a ground-water-flow model to accurately simulate existing or future ground-water and surface-water conditions, accurate estimates of specific input variables such as streambed conductance or canal-seepage rates are required. As of 2008, the values input into ground-water models were estimated on the basis of interpreted lithology from test holes and geophysical surveys. Often, contrasts of several orders of magnitude exist for streambed conductance among the various sediment textures present locally, and thin, near-surface layers of fine sediment can clog the streambed, substantially reducing conductance. To accurately quantify the rates of leakage from irrigation canals and estimate ground-water recharge, the U.S. Geological Survey, in cooperation with the North Platte Natural Resources District, collected continuous temperature and water-level data to use heat as a tracer for a selected reach of Tri-State Canal west of Scottsbluff, Nebraska. Continuous records of subsurface temperature, ground-water level, canal stage, and water temperature, and sediment core data are presented in this report. Subsurface temperature was monitored at four vertical sensor arrays of thermocouples installed at various depths beneath the canal bed from March through September 2007. Canal stage and water temperature were measured from June to September 2007. Ground-water level was recorded continuously in an observation well drilled near the subsurface temperature monitoring site. These data sets were collected for use as inputs for a computer model to estimate the vertical hydraulic conductivity. Before the initiation of flow, diurnal variations in subsurface temperature occurred because of daytime heating and nighttime cooling of bed sediment. Flow in Tri-State Canal was first detected on June 16 at the monitoring site as a disruption in the temperature signal in the shallowest thermocouple in all four vertical sensor arrays. This disruption in the temperature pattern occurred in deeper thermocouples at slightly later times during the rapid infiltration of canal water. The ground-water level began to rise approximately 23 hours after flow was first detected at the monitoring site. Canal stage rose for 7 days until the maximum flow capacity of the canal was approached on June 23, 2007. Measured water temperatures ranged from 18 to 25 degrees Celsius (C) while the canal was flowing near maximum capacity. Small diurnal variations of 1.0 to 1.5 degrees C in water temperature were recorded during this time. Measured ground-water levels rose constantly during the entire irrigation season until levels peaked on September 3, 2007, 3 days after diversions to Tri-State Canal ceased.

Data Series↗
USGS2025

Fisheries research and monitoring activities of the Lake Erie Biological Station, 2024

A comprehensive understanding of fish populations and their interactions is the cornerstone of modern fishery management and the basis for Lake Erie’s Fish Community Objectives (FCOs) developed in 2020 (Francis et al. 2020). The 2024 U.S. Geological Survey (USGS) Lake Erie Biological Station Annual Report is responsive to these FCOs and the USGS obligations via a Memorandum of Understanding (MOU 2017) with the Great Lakes Fishery Commission (GLFC) Council of Lake Committees (CLC) to provide scientific information in support of fishery management. Goals for the USGS Great Lakes Deepwater Fish Assessment and Ecological Studies were to monitor long-term changes in the fish community and track population dynamics of key fishes of interest to management agencies. Specific to Lake Erie, expectations were sustained investigations of native percids, prey fish populations, and Lake Trout. All work was conducted as part of the Deepwater Science Program under the authority of the Great Lakes Fishery Research Authorization Act of 2019 (16 USC §941h). The USGS 2024 Deepwater Science Program fieldwork began in Lake Erie in March and concluded in December, using trawl, gill net, hydroacoustic, lower trophic sampling devices, and telemetry methods. This work resulted in 44 bottom trawls covering 41 ha of lake bottom and catching 48,936 fish totaling 995 kg in the West Basin of Lake Erie, with detailed results described below. Overnight gill net sets (n=25) for coldwater species were performed in the East Basin of Lake Erie. A total of 8 km of gillnet was deployed during these surveys, which caught 106 fish, 92 of which were native coldwater species: Lake Trout, Burbot, and Lake Whitefish. Results from coldwater species assessments will be reported in the Coldwater Task Group report to the GLFC and the CLC (CTG 2025). These reports are used to inform Lake Trout stocking decisions and direct lamprey control measures (16 USC §939a). USGS hydroacoustic sampling included twenty-six 5-km transects (130 km total) in the Central Basin as part of a collaborative lake-wide survey with details and results reported by the Forage Task Group (FTG 2025). Lower trophic sampling provided data from zooplankton samples (n=12) and water quality profiles (n=12) to populate a database maintained by the Michigan Department of Natural Resources (MDNR), Ontario Ministry of Natural Resources (OMNR), Ohio Department of Natural Resources (ODNR), Pennsylvania Fish and Boat Commission (PFBC), and New York State Department of Environmental Conservation (NYSDEC). USGS also assisted CLC member agencies with deployment and maintenance of Great Lakes Acoustic Telemetry Observation System (GLATOS) infrastructure throughout all three Lake Erie basins and tributaries, supporting multiple coordinated telemetry investigations. This report presents biomass-based summaries of fish communities in western Lake Erie derived from USGS bottom trawl surveys conducted from 2013 to 2024 during June and September. The survey design compliments the August ODNR- OMNRF effort by reinforcing stock assessments with more robust data. Analyses herein evaluated trends in total biomass, abundance of dominant predator and forage species, non-native species composition, biodiversity, and community structure. Data from this effort are accessible for download (Keretz et al. 2025)

Lake Erie↗
USGS2015

Information resources

During recent decades, natural resources agency personnel and others involved with the management and stewardship of wildlife have experienced an increasing need to access information and obtain technical assistance for addressing a diverse array of wildlife disease issues. This Chapter provides a broad overview of selected sources for obtaining supplemental information and technical assistance for addressing wildlife disease issues in North America. Specifically, examples of existing major wildlife disease programs focusing on free-ranging wildlife populations are highlighted; training opportunities for enhancing within-agency wildlife disease response are identified; a selected reading list of wildlife disease references is provided; and selected Web sites providing timely information on wildlife disease are highlighted. No attempt is made to detail all the North American programs and capabilities that address disease in free-ranging wildlife populations. Instead, this Chapter is focused on enhancing awareness of the types of capabilities that exist as potential sources for assistance and collaboration between wildlife conservation agency personnel and others in addressing wildlife disease issues. A wide variety of entities across North America are involved in wildlife disease investigations; however, the formal assembly of multidimensional programs that primarily address disease for the benefit of free-ranging wildlife is rather limited. The Southeastern Cooperative Wildlife Disease Study (SCWDS), the National Wildlife Health Center (NWHC), and the Canadian Wildlife Health Cooperative (CWHC) are selected examples. These programs are highlighted because of the scope of their capabilities and long-term involvement in assisting State and Federal natural resource agencies combat wildlife disease. A variety of other sources for possible assistance in addressing wildlife disease issues exists throughout North America and globally. It is prudent for wildlife conservation field biologists, managers, and administrators to be aware of such local resources. Ideally, awareness and knowledge of the types of assistance those programs can provide should be obtained prior to disease crisis events since appropriate, timely intervention often is required to minimize wildlife losses from disease and prevent the establishment of new infectious diseases within wildlife populations and geographic areas. Increasing recognition of the substantial number of infectious diseases being transferred between wildlife, domestic animals, and humans has led to increased collaborative investigations between wildlife, domestic, and human health programs. That collaboration has led to a heightened focus on wildlife disease within some public health and agriculture agencies. For purposes of this Chapter, wildlife disease is narrowly defined as those diseases (infectious and noninfectious) causing morbidity and mortality in free-ranging wildlife populations. Therefore, there is no focus on the numerous fish disease or environmental contaminant programs that exist on behalf of North American fauna.

Techniques and Methods↗
USGS2019

Groundwater movement and interaction with surface water near the confluence of the Platte and Elkhorn rivers, Nebraska, 2016–18

The State of Nebraska requires a sustainable balance between long-term water supplies and uses of groundwater and surface water and requires Natural Resources Districts to include the effect of groundwater use on surface-water systems as part of their respective integrated management plans. Recent droughts in Nebraska (2000–6; 2012–13) have amplified concerns about the long-term sustainability of groundwater and surface-water resources in the state, and concerns about the effect of groundwater irrigation on both streamflow and the water supplies needed to meet wildlife, recreational, and municipal needs. The lower Platte River provides nearly 100 percent of drinking-water supplies to Lincoln, Nebraska, 40 to 60 percent of drinking-water supplies to Omaha, Nebr., and critical aquatic and riparian habitat for threatened and endangered species. The Lower Platte River Basin-wide Management Plan has been jointly developed by the Nebraska Department of Natural Resources and seven Natural Resources Districts to address some of these concerns by managing groundwater and surface-water resources conjunctively. To sustain flows in the lower Platte River that are needed for municipal water supplies, water managers have proposed projects aimed at temporary storage of surface water in upstream parts of the basin to mitigate periods of low flow in the lower Platte River. To increase scientific understanding and provide support for any potential future streamflow augmentation projects, the Papio-Missouri River Natural Resources District, the Lower Platte North Natural Resources District, and the Nebraska Department of Natural Resources, in cooperation with the U.S. Geological Survey, initiated this study to examine groundwater/surface-water interaction along the lower Platte and Elkhorn Rivers upstream from their confluence. The study design described herein focused on understanding seasonal characteristics of groundwater movement and interaction with surface water during periods of high groundwater demand (June through August) and low groundwater demand (all other months). Understanding how groundwater movement and interaction with surface water are affected by streamflow conditions and local groundwater demand is critical to the development of any streamflow augmentation project intended to sustain streamflow and mitigate periods of low flow in the lower Platte River. The characteristics of groundwater movement and interaction with surface water are affected by hydrologic and local climatic conditions. For the study area, 2016–18 conditions can be broadly characterized as above normal precipitation. The flows measured at the Elkhorn River at Waterloo, Nebr., streamflow-gaging station (U.S. Geological Survey station 06800500) were above the long-term median, and the streamflow of the Platte River near Leshara, Nebr., streamflow-gaging station (06796500) remained normal or slightly above normal for the duration of this study. Continuous streamflow and water-level data were interpreted to examine differences in groundwater movement and interaction with surface water between the Platte and Elkhorn Rivers during high and low groundwater demand periods. Although the streamflow for the Platte and Elkhorn Rivers and their tributaries was less during the high groundwater demand period, the hydraulic gradient along a transect of recorder wells was identical (0.0012 foot per foot) during the high and low groundwater demand synoptic water-level and streamflow surveys. The hydraulic gradient between the Platte and Elkhorn Rivers generally remained between 0.0011 and 0.0012 foot per foot. It can be inferred that the hydraulic gradient, which is the only temporally variable factor in Darcy’s Law, is consistent throughout the study period and that groundwater flow does not vary appreciably along this transect. The northern part of the study area (north of the transect of recorder wells) has consistent groundwater and tributary flow from Big Slough, Rawhide Creek (Old Channel), and Rawhide Creek for low and high groundwater demand periods. In the southern part of the study area (south of the transect of recorder wells), tributary flow is more variable and dependent on local groundwater demand and flow conditions of the Platte River. Small decreases (less than 2 feet) in the groundwater levels, such as those measured during the high groundwater demand period, can have substantial changes in the streamflow in an unnamed tributary to the Elkhorn River. The streamflow measured during the high groundwater demand synoptic water-level and streamflow survey had decreased by nearly a factor of 20 when compared to the low groundwater demand period. The volume of groundwater discharge received by the Elkhorn River was estimated by examining the changes in streamflow between measurement locations. Streamflow measurements indicate that the groundwater discharge received by the Elkhorn River in the southern part of the study area was seasonably variable, making it difficult if not impossible to estimate an annual value. In the Elkhorn River, between the Elkhorn River at Waterloo, Nebr., streamflow-gaging station and the Q Street Bridge, streamflow measurements collected during the low groundwater demand period indicated a gain of 80 cubic feet per second, which is comparable to the gain estimated using aerial thermal infrared imagery and water temperature data. Streamflow measurements collected during the high groundwater demand period indicate a loss of 80 cubic feet per second across this same reach. In assessing water supply conditions in the lower Platte River system, the term “loss” in reference to streamflow in the Elkhorn River should be used with caution. Most likely, flow from the Elkhorn River which is “lost” to the groundwater system will later discharge to surface water closer to the confluence of the Platte and Elkhorn Rivers as underflow. A calibrated groundwater flow model of the study area likely is required to predict the fate of this water and to quantify groundwater discharge during varying hydrologic conditions along this reach. Aerial thermal infrared imagery indicated that much of the groundwater discharge in the southern part of the study area is focused across a 3-mile reach where the Elkhorn River turns southwest, perpendicular to the regional groundwater flow direction. Points of focused groundwater discharge were not detected with aerial thermal infrared imagery, indicating that groundwater discharge is diffuse rather than concentrated at focused points. Temperature-based streambed flux estimates indicated that strong regional groundwater gradients are not driving groundwater discharge and hyporheic flow is the dominant groundwater/surface-water exchange process.

Nebraska↗
USGS2014

Airborne geophysical surveys conducted in western Nebraska, 2010: contractor reports and data

This report contains three contractor reports and data files for an airborne electromagnetic survey flown from June 28 to July 7, 2010. The first report; “SkyTEM Survey: Nebraska, USA, Data” describes data aquisition and processing from a time-domain electromagnetic and magnetic survey performed by SkyTEM Canada, Inc. (the North American SkyTEM subsidiary), in western Nebraska, USA. Digital data for this report are given in Appendix 1. The airborne geophysical data from the SkyTEM survey subsequently were processed and inverted by Aarhus Geophysics ApS, Aarhus, Denmark, to produce resistivity depth sections along each flight line. The result of that processing is described in two reports presented in Appendix 2, “Processing and inversion of SkyTEM data from USGS Area UTM–13” and “Processing and inversion of SkyTEM data from USGS Area UTM–14.” Funding for these surveys was provided by the North Platte Natural Resources District, the South Platte Natural Resources District, and the Twin Platte Natural Resources District, in Scottsbluff, Sidney, and North Platte, Nebraska, respectively. Any additional information concerning the geophysical data may be obtained from the U.S. Geological Survey Crustal Geophysics and Geochemistry Science Center, Denver Colorado.

Nebraska↗
USGS2004

Conventional natural gas resource potential, Alaska North Slope

An estimate of total natural gas resource potential of northern Alaska can be obtained by summing known gas reserves in oil and gas fields (35 TCF), mean estimates of undiscovered nonassociated (61 TCF) and associated (12 TCF) gas resources in NPRA, and mean estimates of undiscovered nonassociated (4 TCF) and associated (5 TCF) gas resources in the 1002 area of ANWR; this yields a total of 117 TCF. When estimates of undiscovered gas resources for non-Federal lands are released in 2005, that total will increase by a non-trivial amount. Thus, the conventional natural gas resource potential of onshore and State offshore areas totals well over 100 TCF. The inclusion of the MMS mean estimate (96 TCF) for undiscovered gas resources in the Beaufort and Chukchi planning areas of the Federal offshore extends that total above 200 TCF.

Open-File Report↗