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USGS2005

Broad-scale predictors of canada lynx occurrence in eastern North America

The Canada lynx (Lynx canadensis) is listed as a threatened species throughout the southern extent of its geographic range in the United States. Most research on lynx has been conducted in the western United States and Canada; little is known about the ecology of lynx in eastern North America. To fill critical knowledge gaps about this species, we modeled and mapped lynx occurrence using habitat and weather data from 7 eastern states and 3 Canadian provinces. Annual snowfall, road density, bobcat (L. rufus) harvest, deciduous forest, and coniferous forest were compared at 1,150 lynx locations and 1,288 random locations. Nineteen a priori models were developed using the information-theoretic approach, and logistic regression models were ranked using Akaike's Information Criterion (AIC) and by our ability to correctly classify reserved data (Kappa). Annual snowfall and deciduous forest predicted lynx presence and absence for a reserved dataset (n = 278) with 94% accuracy. A map of the probability of lynx occurrence throughout the region revealed that 92% of the potential habitat (i.e., >50% probability of occurrence) was concentrated in a relatively contiguous complex encompassing northern Maine, New Brunswick, and the Gaspe?? peninsula of Quebec. Most of the remaining potential habitat (5%) was on northern Cape Breton Island in Nova Scotia. Potential habitat in New Hampshire, Vermont, and New York was small (1,252 km2), fragmented, and isolated (>200 km) from known lynx populations. When federally listed as threatened in the contiguous United States in 2000, inadequate regulations on federal lands were cited as the primary threat to Canada lynx. However, the majority of potential lynx habitat in the eastern United States is on private lands and continuous with potential habitat in Canada. Therefore, lynx conservation in eastern North America will need to develop partnerships across national, state, and provincial boundaries as well as with private landowners.

Journal of Wildlife Management↗

USGS1981

Maps for America: cartographic products of the U.S. Geological Survey and others

"Maps for America" was originally published in 1979 as a Centennial Volume commemorating the Geological Survey's hundred years of service (1879-1979) in the earth sciences. It was an eminently fitting Centennial Year publication, for, since its establishment, the Geological Survey has continuously carried on an extensive program of mapping to provide knowledge of the topography, geology, hydrology, and natural resources of our Nation. This volume contains an organized presentation of information about the maps produced by the Geological Survey and other American organizations, public and private. Such maps are important tools for those in government and in private endeavors who are working to assure the wisest choices in managing the Nation's resources. They are particularly supportive of the Department of the Interior's role as the Nation's principal conservation agency. The second edition of "Maps for America" is intended primarily to replenish the dwindling supply of copies of the book, but it also contains a number of changes to correct or update the text and to provide more suitable illustrations in certain instances.

Report↗

USGS1988

Maps for America: cartographic products of the U.S. Geological Survey and others

"Maps for America" was originally published in 1979 as a Centennial Volume commemorating the Geological Survey's hundred years of service (1879 - 1979) in the earth sciences. It was an eminently fitting Centennial Year publication, for, since its establishment, the Geological Survey has continuously carried on an extensive program of mapping to provide knowledge of the topography, geology, hydrology, and natural resources of our nation. This volume contains an organized presentation of information about the map produced by the Geological Survey and other American organizations, public and private. Such maps are important tools for those in government and in private endeavors who are working to assure the wisest choices in managing the Nation's resources. They are particularly supportive of the Department of the Interior's role as the Nation's principal conservation agency. The third edition of "Maps for America," like the second edition, is intended primarily to replenish the supply of copies of the book, but it also contains a number of changes to correct or update the text.

Report↗

USGS2002

Magnetic anomaly map of North America

This digital Magnetic Anomaly database and map for the North American continent is the result of a joint effort by the Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM). The database and map represent a substantial upgrade from the previous compilation of Magnetic Anomaly data for North America, now over a decade old (Committee for the Magnetic Anomaly Map of North America, 1987). This integrated, readily accessible, modern digital database of magnetic anomaly data will be a powerful tool for further evaluation of the structure, geologic processes, and tectonic evolution of the continent and may also be used to help resolve societal and scientific issues that span national boundaries. The North American magnetic anomaly map derived from the digital database provides a comprehensive magnetic view of continental-scale trends not available in individual data sets, helps link widely separated areas of outcrop, and unifies disparate geologic studies. This booklet outlines the data processing and compilation procedures used to produce the magnetic anomaly database and map that accompany this booklet.

Special Map↗

USGS1957

Mineral deposits of Central America, with a section on manganese deposits of Panama

The mineral deposits of Central America were studied between 1942 and 1945, in cooperation with the United States Department of State and the Foreign Economic Administration. Emphasis was originally placed on the study of strategic-mineral deposits, especially of antimony, chromite, manganese, quartz, and mica, but deposits of other minerals that offered promise of significant future production were also studied. A brief appraisal of the base-metal deposits was made, and deposits of iron ore in Honduras and of lead and zinc ores in Guatemala were mapped. In addition, studies were made of the regional geology of some areas, data were collected from many sources, and a new map of the geology of Central America was compiled.

Central America↗

USGS2022

Database of the "North America Tapestry of Time and Terrain" map

In 2000, the U.S. Geological Survey published a distinctive map, entitled “A Tapestry of Time and Terrain,” which showed a generalized depiction of the geology in the conterminous United States, draped over shaded-relief topography. In 2003, that map concept was extended geographically, and the resulting new map was published at 1:8,000,000 scale as “The North America Tapestry of Time and Terrain” (NATTT). The NATTT map showed the wide range of ages of the bedrock that underlies North America, as well as the distribution of the principal rock types— sedimentary, igneous (as two subtypes, volcanic and plutonic), and metamorphic. Regional processes active at the land surface, as well as continental-scale tectonic events, are exposed on the maps, in the three dimensions of space and in the fourth dimension, geologic time. This new publication contains the geographic information system (GIS) data from the NATTT map, which, in turn, includes map data from the earlier Tapestry map. The GIS files contain over 20,000 polygons that represent geologic age and rock class. In addition, layer files are provided to facilitate a symbolized display of the map that is similar to that of the original NATTT map publication. The data are intended to be used at the scale of the published source map (1:8,000,000).

Data Series↗

USGS2002

Modified Mercalli Intensities (MMI) for some earthquakes in eastern North America (ENA) and empirical MMI site corrections for towns in ENA

Modified Mercalli Intensity (MMI) assignments for earthquakes in eastern North America (ENA) were used by Bakun et al. (submitted) to develop a model for eastern North America for estimating the location and moment magnitude M of earthquakes from MMI observations. MMI assignments for most of the earthquakes considered by Bakun et al. (submitted) are published. MMI assignments for 6 other earthquakes used by Bakun et al. (submitted) are listed in this report: November 18, 1755 near Cape Ann, Massachusetts; January 5, 1843 near Marked Tree, Arkansas; October 31, 1895 in southern Illinois; November 18, 1929 on the Grand Banks, Newfoundland; September 26, 1990 in southeast Missouri; and May 4, 1991 near Risco, Missouri. MMI empirical site corrections developed and used by Bakun et al. (submitted) are also listed in this report.

Arkansas;Illinois;Massachusetts;Missouri;Newfoundl↗

USGS2008

Quantitative mineral resource assessment of copper, molybdenum, gold, and silver in undiscovered porphyry copper deposits in the Andes Mountains of South America

Quantitative information on the general locations and amounts of undiscovered porphyry copper resources of the world is important to exploration managers, land-use and environmental planners, economists, and policy makers. This publication contains the results of probabilistic estimates of the amounts of copper (Cu), molybdenum (Mo), gold (Au), and silver (Ag) in undiscovered porphyry copper deposits in the Andes Mountains of South America. The methodology used to make these estimates is called the 'Three-Part Form'. It was developed to explicitly express estimates of undiscovered resources and associated uncertainty in a form that allows economic analysis and is useful to decisionmakers. The three-part form of assessment includes: (1) delineation of tracts of land where the geology is permissive for porphyry copper deposits to form; (2) selection of grade and tonnage models appropriate for estimating grades and tonnages of the undiscovered porphyry copper deposits in each tract; and (3) estimation of the number of undiscovered porphyry copper deposits in each tract consistent with the grade and tonnage model. A Monte Carlo simulation computer program (EMINERS) was used to combine the probability distributions of the estimated number of undiscovered deposits, the grades, and the tonnages of the selected model to obtain the probability distributions for undiscovered metals in each tract. These distributions of grades and tonnages then can be used to conduct economic evaluations of undiscovered resources in a format usable by decisionmakers. Economic evaluations are not part of this report. The results of this assessment are presented in two principal parts. The first part identifies 26 regional tracts of land where the geology is permissive for the occurrence of undiscovered porphyry copper deposits of Phanerozoic age to a depth of 1 km below the Earth's surface. These tracts are believed to contain most of South America's undiscovered resources of copper. The second part presents probabilistic estimates of the amounts of copper, molybdenum, gold, and silver in undiscovered porphyry copper deposits in each tract. The study also provides tables showing the location, tract number, and age (if available) of discovered deposits and prospects. For each of the 26 permissive tracts delineated in this study, summary information is provided on: (1) the rationale for delineating the tract; (2) the rationale for choosing the mineral deposit model used to assess the tract; (3) discovered deposits and prospects; (4) exploration history; and (5) the distribution of undiscovered deposits in the tract. The scale used to evaluate geologic information and draw tracts is 1:1,000,000.

Open-File Report↗

USGS2008

GIS Representation of Coal-Bearing Areas in North, Central, and South America

Worldwide coal consumption and international coal trade are projected to increase in the next several decades (Energy Information Administration, 2007). A search of existing literature indicates that in the Western Hemisphere, coal resources are known to occur in about 30 countries. The need exists to be able to depict these areas in a digital format for use in Geographic Information System (GIS) applications at small scales (large areas) and in visual presentations. Existing surficial geology GIS layers of the appropriate geologic age have been used as an approximation to depict the extent of coal-bearing areas in North, Central, and South America, as well as Greenland (fig. 1). Global surficial geology GIS data were created by the U.S. Geological Survey (USGS) for use in world petroleum assessments (Hearn and others, 2003). These USGS publications served as the major sources for the selection and creation of polygons to represent coal-bearing areas. Additional publications and maps by various countries and agencies were also used as sources of coal locations. GIS geologic polygons were truncated where literature or hardcopy maps did not indicate the presence of coal. The depicted areas are not adequate for use in coal resource calculations, as they were not adjusted for geologic structure and do not include coal at depth. Additionally, some coal areas in Central America could not be represented by the mapped surficial geology and are shown only as points based on descriptions or depictions from scientific publications or available maps. The provided GIS files are intended to serve as a backdrop for display of coal information. Three attributes of the coal that are represented by the polygons or points include geologic age (or range of ages), published rank (or range of ranks), and information source (published sources for age, rank, or physical location, or GIS geology base).

Open-File Report↗

USGS2011

Dynamically downscaled climate simulations over North America: Methods, evaluation, and supporting documentation for users

We have completed an array of high-resolution simulations of present and future climate over Western North America (WNA) and Eastern North America (ENA) by dynamically downscaling global climate simulations using a regional climate model, RegCM3. The simulations are intended to provide long time series of internally consistent surface and atmospheric variables for use in climate-related research. In addition to providing high-resolution weather and climate data for the past, present, and future, we have developed an integrated data flow and methodology for processing, summarizing, viewing, and delivering the climate datasets to a wide range of potential users. Our simulations were run over 50- and 15-kilometer model grids in an attempt to capture more of the climatic detail associated with processes such as topographic forcing than can be captured by general circulation models (GCMs). The simulations were run using output from four GCMs. All simulations span the present (for example, 1968-1999), common periods of the future (2040-2069), and two simulations continuously cover 2010-2099. The trace gas concentrations in our simulations were the same as those of the GCMs: the IPCC 20th century time series for 1968-1999 and the A2 time series for simulations of the future. We demonstrate that RegCM3 is capable of producing present day annual and seasonal climatologies of air temperature and precipitation that are in good agreement with observations. Important features of the high-resolution climatology of temperature, precipitation, snow water equivalent (SWE), and soil moisture are consistently reproduced in all model runs over WNA and ENA. The simulations provide a potential range of future climate change for selected decades and display common patterns of the direction and magnitude of changes. As expected, there are some model to model differences that limit interpretability and give rise to uncertainties. Here, we provide background information about the GCMs and the RegCM3, a basic evaluation of the model output and examples of simulated future climate. We also provide information needed to access the web applications for visualizing and downloading the data, and give complete metadata that describe the variables in the datasets.

Open-File Report↗

USGS2000

Maps showing geology, oil and gas fields and geologic provinces of the South America region

This digitally compiled map includes geology, geologic provinces, and oil and gas fields of South America. The map is part of a worldwide series on CD-ROM by World Energy Project released of the U.S. Geological Survey . The goal of the project is to assess the undiscovered, technically recoverable oil and gas resources of the world and report these results by the year 2000. For data management purposes the world is divided into eight energy regions corresponding approximately to the economic regions of the world as defined by the U.S. Department of State. South America (Region 6) includes Argentina, Bolivia, Brazil, Chile, Columbia, Ecuador, Falkland Islands, French Guiana, Guyuna, Netherlands, Netherlands Antilles, Paraguay, Peru, Suriname, Trinidad and Tobago, Uruguay, and Venezuela.

Open-File Report↗

USGS2000

Atlas of relations between climatic parameters and distributions of important trees and shrubs in North America; additional conifers, hardwoods, and monocots

This volume explores the continental-scale relations between climate and the geographic ranges of woody plant species in North America. A 25-km equal-area grid of modern climatic and bioclimatic parameters for North America was constructed from instrumental weather records. The geographic distributions of selected tree and shrub species were digitized, and the presence or absence of each species was determined for each cell on the 25-km grid, thus providing a basis for comparing climatic data and species' distribution.

Professional Paper↗

USGS2006

Atlas of relations between climatic parameters and distributions of important trees and shrubs in North America - Alaska species and ecoregions

Climate is the primary factor in controlling the continental-scale distribution of plant species, although the relations between climatic parameters and species' ranges is only now beginning to be quantified. Preceding volumes of this atlas explored the continental-scale relations between climatic parameters and the distributions of woody plant species across all of the continent of North America. This volume presents similar information for important woody species, groups of species, and ecoregions in more detail for the State of Alaska. For these analyses, we constructed a 25-kilometer equal-area grid of modern climatic and bioclimatic parameters for North America from instrumental weather records. We obtained a digital representation of the geographic distribution of each species or ecoregion, either from a published source or by digitizing the published distributions ourselves. The presence or absence of each species or ecoregion was then determined for each point on the 25-kilometer grid, thus providing a basis for comparison of the climatic data with the geographic distribution of each species or ecoregion. The relations between climate and these distributions are presented in graphical and tabular form.

Alaska↗

USGS2007

Detection of group 1 coronaviruses in bats in North America

The epidemic of severe acute respiratory syndrome (SARS) was caused by a newly emerged coronavirus (SARS-CoV). Bats of several species in southern People's Republic of China harbor SARS-like CoVs and may be reservoir hosts for them. To determine whether bats in North America also harbor coronaviruses, we used reverse transcription-PCR to detect coronavirus RNA in bats. We found coronavirus RNA in 6 of 28 fecal specimens from bats of 2 of 7 species tested. The prevalence of viral RNA shedding was high: 17% in Eptesicus fuscus and 50% in Myotis occultus. Sequence analysis of a 440-bp amplicon in gene 1b showed that these Rocky Mountain bat coronaviruses formed 3 clusters in phylogenetic group 1 that were distinct from group 1 coronaviruses of Asian bats. Because of the potential for bat coronaviruses to cause disease in humans and animals, further surveillance and characterization of bat coronaviruses in North America are needed.

Emerging Infectious Diseases↗

USGS2018

Introduction of Eurasian-origin H8N4 influenza A virus into North America via migratory birds

We identified a Eurasian-origin influenza A(H8N4) virus in North America by sampling wild birds in western Alaska, USA. Evidence for repeated introductions of influenza A viruses into North America by migratory birds suggests that intercontinental dispersal might not be exceedingly rare and that our understanding of viral establishment is incomplete.

Emerging Infectious Diseases↗

USGS2004

Myxobolus cerebralis internal transcribed spacer 1 (ITS-1) sequences support recent spread of the parasite to North America and within Europe

Molecular approaches for resolving relationships among the Myxozoa have relied mainly on small subunit (SSU) ribosomal DNA (rDNA) sequence analysis. This region of the gene is generally used for higher phylogenetic studies, and the conservative nature of this gene may make it inadequate for intraspecific comparisons. Previous intraspecific studies of Myxobolus cerebralis based on molecular analyses reported that the sequence of SSU rDNA and the internal transcribed spacer (ITS) were highly conserved in representatives of the parasite from North America and Europe. Considering that the ITS is usually a more variable region than the SSU, we reanalyzed available sequences on GenBank and obtained sequences from other M. cerebralis representatives from the states of California and West Virginia in the USA and from Germany and Russia. With the exception of 7 base pairs, most of the sequence designated as ITS-1 in GenBank was a highly conserved portion of the rDNA near the 3-prime end of the SSU region. Nonetheless, the additional ITS-1 sequences obtained from the available geographic representatives were well conserved. It is unlikely that we would have observed virtually identical ITS-1 sequences between European and American M. cerebralis samples had it spread naturally over time, particularly when compared to the variation seen between isolates of another myxozoan ( Kudoa thyrsites ) that has most likely spread naturally. These data further support the hypothesis that the current distribution of M. cerebralis in North America is a result of recent introductions followed by dispersal via anthropogenic means, largely through the stocking of infected trout for sport fishing.

Diseases of Aquatic Organisms↗

USGS2019

Genetic variation among island and continental populations of Burrowing Owl (Athene cunicularia) subspecies in North America

Burrowing Owls ( Athene cunicularia ) have a large geographic range spanning both North and South America and resident populations occur on many islands in the eastern Pacific Ocean and the Caribbean Sea. Many owl populations are isolated and disjunct from other populations, but studies on genetic variation within and among populations are limited. We characterized DNA microsatellite variation in populations varying in size and geographic isolation in the Florida ( A. c. floridana ), the Western ( A. c. hypugaea ), and the Clarion ( A. c. rostrata ) subspecies of the Burrowing Owl. We also characterized genetic variation in a geographically isolated population of the western subspecies in central Mexico (near Texcoco Lake). Clarion Burrowing Owls had no intrapopulation variation (i.e., fixation) at 5 out of 11 microsatellite loci, a likely outcome of genetic drift in an isolated and small population. The Florida subspecies had only polymorphic loci but had reduced levels of genetic variation compared with the more-widespread western subspecies that occurs throughout western North America. Despite the extensive geographic distribution of the Western Burrowing Owl, we found genetic differentiation between the panmictic population north of the Trans-Mexican Volcanic Belt and the resident Texcoco Lake population in central Mexico.

Journal of Raptor Research↗

USGS2024

Preparing for a Bsal invasion into North America has improved multi-sector readiness

Western palearctic salamander susceptibility to the skin disease caused by the amphibian chytrid fungus Batrachochytrium salamandrivorans (Bsal) was recognized in 2014, eliciting concerns for a potential novel wave of amphibian declines following the B. dendrobatidis (Bd) chytridiomycosis global pandemic. Although Bsal had not been detected in North America, initial experimental trials supported the heightened susceptibility of caudate amphibians to Bsal chytridiomycosis, recognizing the critical threat this pathogen poses to the North American salamander biodiversity hotspot. Here, we take stock of 10 years of research, collaboration, engagement, and outreach by the North American Bsal Task Force. We summarize main knowledge and conservation actions to both forestall and respond to Bsal invasion into North America. We address the questions: what have we learned; what are current challenges; and are we ready for a more effective reaction to Bsal’s eventual detection? We expect that the many contributions to preemptive planning accrued over the past decade will pay dividends in amphibian conservation effectiveness and can inform future responses to other novel wildlife diseases and extreme threats.

North America↗