US Topo maps now have a crisper, cleaner design - enhancing readability of maps for online and printed use. Map symbols are easier to read over the digital aerial photograph layer whether the imagery is turned on or off. Improvements to symbol definitions (color, line thickness, line symbols, area fills), layer order, and annotation fonts are additional features of this supplemental release. Users can now adjust the transparency for some features and layers to increase visibility of multiple competing layers.
This new design was launched earlier this year and is now part of the new US Topo quadrangles for West Virginia (418 maps), New Jersey (150) and Georgia (952 maps), replacing the first edition US Topo maps for those states.
“Users in West Virginia will appreciate improvements in the US Topo product, including the availability of improved contours, Forest Service trails, and vegetation cover (green tint),” said Craig Neidig, USGS Geospatial Liaison for West Virginia. “The product should find an audience among the many recreational users and outdoor enthusiasts in West Virginia, especially with the capability to use the US Topo maps on mobile devices. We look forward to the addition of layers including mining sites, wetlands, and more historic features that users were accustomed to seeing on the old topographic quadrangles for the Mountain State.”
US Topo maps are updated every three years. The initial round of the 48 conterminous states coverage was completed in September of 2012. Hawaii and Puerto Rico maps have recently been added. More than 400 new US Topo maps for Alaska have been added to the USGS Map Locator & Downloader, but will take several years to complete.
Re-design enhancements and new features:
- Crisper, cleaner design improves online and printed readability while retaining the look and feel of traditional USGS topographic maps
- New functional road classification schema has been applied
- A slight screening (transparency) has been applied to some features to enhance visibility of multiple competing layers
- Updated free fonts that support diacritics
- New PDF Legend attachment
- Metadata formatted to support multiple browsers
- New shaded relief layer for enhanced view of the terrain
- Military installation boundaries, post offices and cemeteries
- Starting with Georgia, the railroad dataset is much more complete from a new contractor
To enjoy earlier legacy quads for West Virginia, New Jersey and Georgia, go to the USGS Historical Topographic Map Collection. These scanned images of paper maps up through 2006 are also available for free download from The National Map and the USGS Map Locator & Downloader website.
US Topo maps are created from geographic datasets in The National Map, and deliver visible content such as high-resolution aerial photography, which was not available on older paper-based topographic maps. The new US Topo maps provide modern technical advantages that support wider and faster public distribution and on-screen geographic analysis tools for users. The new digital electronic topographic maps are delivered in GeoPDF image software format and may be viewed using Adobe Reader, available as a no cost download.
For more information, go to: http://nationalmap.gov/ustopo/Historical map of the Cass, West Virginia area, 1922. (high resolution image 1.8 MB) US Topo map of the Cass, West Virginia quadrangle, March 2014. (high resolution image 1.2 MB)
Screen shot of a mobile mapping service integrating USGS topographic data; hiking and biking trails south of Golden, Colo. (larger image)
Are you a developer, firm, or organization using mobile or web applications to enable your users? The USGS has publicly available geospatial services and data to help you!
The USGS’ National Geospatial Technical Operations Center (NGTOC) will be hosting a 30 minute Webinar on “Using The National Map services to enable your web and mobile mapping efforts” on the 30th of April at 9am Mountain Time.
This webinar will feature a brief overview of services, data, and products that are publicly available, a quick overview on how SingleTracks.com (http://www.singletracks.com/) a leading private firm is leveraging this public data to benefit their users, and a Question & Answer session with a USGS developer to help you get the most out of the national geospatial services.
“This is the first webinar from NGTOC to bring developers and users together for some demonstrations and starting some dialog”, said Brian Fox, the NGTOC Systems Development Branch Chief. “Using this webinar format, we can simultaneously improve the awareness of USGS geospatial services and develop a better understanding of what users and developers need to make our data and services more available and usable.”
To access the webinar, you’ll need to activate Adobe WebEx and call into the toll free conference number 855-547-8255 and use the security code: 33220038. The webinar will display through WebEx. Direct link: http://bit.ly/OhNDx5 or browse the selections for that date and time. The WebEx and audio bridge will be live 15 prior to the start time.
To ensure that you have the appropriate players installed for this WebEx enabled Webinar: https://usgs.webex.com/usgs/systemdiagnosis.php
A simultaneous closed caption option will be available at: http://recapd.com/w-a5791c. The session will also be recorded and posted to the webinar website shortly after conclusion.
To find out more about this webinar conference, go to: http://ngtoc.usgs.gov/webinars.html
WASHINGTON. — Mercury has been discovered in fish in some of the most remote national park lakes and streams in the western United States and Alaska. Mercury levels in some fish exceeded U.S. Environmental Protection Agency health thresholds for potential impacts to fish, birds, and humans.
The information about mercury, and its appearance in protected areas considered to be relatively pristine and removed from environmental contaminants, is in a recently published scientific report from the U.S. Geological Survey and National Park Service.
The study of mercury in fish is the first of its kind to incorporate information from remote places at 21 national parks in 10 western states, including Alaska. Western parks were selected for this study because of the significant role that atmospheric mercury deposition plays in remote places, and the lack of broad-scale assessments on mercury in fish in remote areas of the west.
Mercury concentrations in fish sampled from these parks were generally low, but were elevated in some instances. This study examines total mercury in fish, of which 95 percent is in the form of methylmercury, the most dangerous form to human and wildlife health.
Mercury is harmful to human and wildlife health, and is among the most widespread contaminants in the world. It is distributed at a global scale from natural sources, such as volcanic eruptions and from human sources such as burning fossil fuels in power plants. Mercury is distributed at local or regional scales as a result of current and historic mining activities. These human activities have increased levels of atmospheric mercury at least three fold during the past 150 years.
“Although fish mercury concentrations were elevated in some sites, the majority of fish across the region had concentrations that were below most benchmarks associated with impaired health of fish, wildlife, and humans. However, the range of concentrations measured suggest that complex processes are involved in driving mercury accumulation in these environments and further research is needed to better understand these processes, and assess risk,” said USGS ecologist Collin Eagles-Smith, the lead author of the publication.
Between 2008 and 2012, NPS resource managers collected more than 1,400 fish from 86 lakes and rivers, and USGS scientists measured mercury concentrations in fish muscle tissue. Sixteen fish species were sampled, with a focus on commonly consumed sport fish found across the study area such as brook, rainbow, cutthroat, and lake trout. Smaller prey fish consumed by birds and wildlife were also sampled.
Scientists compared fish mercury concentrations among sites within an individual park, as well as from one park to other parks, and identified areas with elevated mercury levels. They also compared the mercury concentrations in the fish to a range of health benchmarks including human health guidelines established by the EPA for fish consumption, and wildlife risk thresholds that indicate the potential for toxicity and impairment in fish and fish-eating birds.
The authors found that mercury levels varied greatly, from park to park and among sites within each park. In most parks, mercury concentrations in fish were moderate to low in comparison with similar fish species from other locations in the Western states. Mercury concentrations were below EPA’s fish tissue criterion for safe human consumption in 96 percent of the sport fish sampled.
The average concentration of mercury in sport fish from two sites in two Alaskan parks exceeded EPA’s human health criterion. Mercury levels in individual fish at some parks from other states including California, Colorado, Washington, and Wyoming also exceeded the human health criterion.
Neither the USGS nor the NPS regulate environmental health guidelines. The NPS is coordinating with state officials in the 10 study states regarding potential fish consumption advisories. State fish consumption guidelines consider both the risks associated with mercury exposure and the benefits of fish consumption, such as improved cardiac health from increased omega-3 fatty acid consumption or potential reduced intake of unhealthy fats due to food substitutions. According to the Centers for Disease Control and Prevention, exposure to high levels of mercury in humans may cause damage to the brain, kidneys, and the developing fetus. Pregnant women and young children are particularly sensitive to the effects of mercury.
Mercury at elevated levels can also impact wildlife. High mercury concentrations in birds, mammals, and fish can result in reduced foraging efficiency, survival, and reproductive success. Mercury concentrations in fish exceeded the most conservative fish toxicity benchmark at 15 percent of all sites, and levels exceeded the most sensitive health benchmark for fish-eating birds at 52 percent of all sites.
Mercury threatens natural resources, including wildlife, which the NPS is mandated to protect. “This is a wake-up call,” said NPS ecologist Colleen Flanagan Pritz, a co-author of the report. “We need to see fewer contaminants in park ecosystems, especially contaminants like mercury where concentrations in fish challenge the very mission of the national parks to leave wild life unimpaired for future generations."
Funding for this study was provided by the NPS Air Resources Division, USGS Contaminants Biology Program within the Environmental Health Mission Area, the Ecosystems Mission Area to the USGS Forest and Rangeland Ecosystem Science Center, and with in-kind contributions from participating parks.
More information is available in the USGS Top Story "Mercury Finds a Way—Even into the Pristine National Parks."
LEETOWN, W.Va. — Great Lakes fish in the salmon family that rely on the fish “alewife” as part of their diet face a major obstacle in restoring naturally reproducing populations, according to new U.S. Geological Survey research published in the journal Fish and Shellfish Immunology.
For more than a decade researchers have been trying to unravel the mystery of why Lake Trout and other salmonids that consume alewife produce spawn that die young. Although researchers have recognized the connection between thiamine and the death of the young fish for a decade, the new study provides an additional clue; fish that survive the initial impact of thiamine deficiency are experiencing changes in immune function that resemble those occurring in humans with inflammatory diseases.
Early Mortality Syndrome, or EMS, results in embryonic mortality in salmon, steelhead trout, brown trout, lake trout, and Chinook salmon. The symptoms of EMS include loss of equilibrium, swimming in a spiral pattern, lethargy, hyper-excitability, hemorrhage and death, which occurs between hatching and first feeding.
“Vitamin B1, or Thiamine, is an essential nutrient that animals must obtain through their diet,” said Chris Ottinger, a USGS immunologist and lead author of the study. “We found that alewives, one of the main diets of many Great Lakes fish, contains an enzyme called “thiaminase” that destroys the thiamine in fish that consume them. The lack of B1 leads to Early Mortality Syndrome as well as the newly reported immune dysfunctions that may be perpetuating infectious diseases in this fish community.”
Alewives were introduced to the Great Lakes as food fish for the species such as lake trout and the introduced Pacific salmon.
“There is some debate as to whether the thiaminase that is obtained through the consumption of the alewives is coming directly from the fish or from bacteria associated with the fish,” said Ottinger. “Either way the fish that eats the alewives becomes thiamine deficient through the destruction of the thiamine they obtain in their diet resulting in EMS as well the immune dysfunctions we have demonstrated.”
Thiamine is essential for energy production in cells, normal nerve function and also is an antioxidant. Other dysfunctions associated with Great Lakes salmonids consumption of alewives include changes in behavior and reduced ability to capture prey.
"In vitro immune function in thiamine-replete and-depleted lake trout (Salvelinus namaycush)" is available online in the journal Fish & Shellfish Immunology by C. A. Ottinger, D. C. Honeyfield, C. L. Densmorea, and L. R. Iwanowicz.
Oyster aquaculture in the Potomac River estuary could result in significant improvements to water quality, according to a new NOAA and U.S. Geological Survey study published in the journal Aquatic Geochemistry.
All of the nitrogen currently polluting the Potomac River estuary could be removed if 40 percent of its river bed were used for shellfish cultivation, according to the joint study. The researchers determined that a combination of aquaculture and restored oyster reefs may provide even larger overall ecosystem benefits. Oysters, who feed by filtering, can clean an enormous volume of water of algae which can cause poor water quality
The study is based on data modeling and an ecosystem-wide scientific evaluation, which examined how activities in the watershed affected the river estuary’s water quality. The research team evaluated nitrogen flows from the Potomac River headwaters and the nutrient-related water quality conditions of the estuary, called eutrophication.
Eutrophication takes place when a body of water becomes enriched in dissolved nutrients that stimulate the growth of aquatic plants, causing nuisance algal blooms. These blooms often result in the depletion of dissolved oxygen and the loss of seagrasses.
The team sought to assess how shellfish aquaculture – specifically oyster aquaculture -- could be used to remove nutrients directly from the water, complementing traditional land-based measures.
Although the estuary bottom area needed to grow oysters to remove the nutrients exists, it is unlikely that such a management measure would be implemented because of conflicting uses. However, a smaller area could still provide great benefits if aquaculture leases were approved. According to the study, if only 15 to 20 percent of the bottom was cultivated it could remove almost half of the incoming nutrients.
“Our study looked to see just how much impact oyster aquaculture could have in restoring some balance to the system,” said Suzanne Bricker, physical scientist in NOAA’s National Centers for Coastal Ocean Science and the paper’s lead author. “Eutrophication conditions in the Potomac River estuary are representative of conditions found in the Chesapeake Bay and many other U.S. estuaries. Historically, waters of the Potomac and other Chesapeake region estuaries were filtered by oysters, but as their populations declined so did their filtration capabilities. This resulted in increased concentrations of nutrients and related water quality concerns, such as algal blooms and low dissolved oxygen.
“The most expedient way to reduce eutrophication in the Potomac River estuary would be to continue reducing land-based nutrients complemented by a combination of aquaculture and restored oyster reefs. The resulting combination could provide significant removal of nutrients and eutrophication impacts directly from the water column, and offer innovative solutions to long-term persistent water quality problems.”
This alternative approach to water quality management has the potential to address legacy pollution, provide a marketable seafood product if there are no other contaminant issues that would prevent human consumption, and enhance local economies with additional income to growers through the possible development of a program -- similar to those being considered in other parts of the country -- where growers would be paid for the water cleaning services done by their oysters.
Flowing into the Chesapeake Bay, the Potomac River is the fourth largest river on the Atlantic coast, with more than six million people living in its watershed. The NOAA and USGS research about human influences on water quality found that the effects of high nutrient levels have not changed overall since the early 1990s. There are, however, some signs of improvement, such as decreased nitrogen loads from the watershed, increased dissolved oxygen and decreased algal blooms in the upper estuary, and continued regrowth of seagrasses.
While scientists have seen signs of improvement, they remain concerned with eutrophication. Dissolved oxygen, a key measure of water quality, is something fish and other aquatic species can’t survive without.
Atmospheric deposition—where gases and particles are released into the atmosphere from combustion of fossil fuels and return to the land as contaminants—also plays a role in polluting the estuary.
“Less attention has been paid to monitoring the effects of atmospheric deposition in headwater streams now that acidic emissions have declined because of the Clean Air Act and Amendments going into effect,” said Karen Rice, USGS research hydrologist. “Nevertheless, monitoring of forested, headwater streams that reflect changes in atmospheric inputs should be continued, if not expanded, so that changes in stream-water quality as related to atmospheric deposition can be tracked.”
The researchers believe the results of the study may be useful on a broad basis, as there are other river-dominated estuaries in the Chesapeake region and elsewhere along the U.S. coastline that could support shellfish aquaculture.
NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join NOAA on Facebook, Twitter and our other social media channels.
Northern sea otters living off the coast of Washington state were infected with the same H1N1 flu virus that caused the world-wide pandemic in 2009, according to a new U.S. Geological Survey and Centers for Disease Control and Prevention study.
During an August 2011 health monitoring project, USGS and CDC scientists found evidence that the Washington sea otters were infected with the pandemic 2009 H1N1 virus, although the exact date and source of exposure could not be determined. The findings suggest that human flu can infect sea otters.
“Our study shows that sea otters may be a newly identified animal host of influenza viruses,” said Hon Ip, a USGS scientist and co-author of the study.
The researchers discovered antibodies for the 2009 H1N1 flu virus in blood samples from 70 percent of the sea otters studied. None of the otters were visibly sick, but the presence of antibodies means that the otters were previously exposed to influenza. Further tests concluded that the antibodies were specific to the pandemic 2009 H1N1 flu virus, and not from exposure to other human or avian H1N1 viruses.
“We are unsure how these animals became infected,” said Zhunan Li, CDC scientist and lead author on the paper. “This population of sea otters lives in a relatively remote environment and rarely comes into contact with humans.”
An unrelated 2010 study showed that northern elephant seals sampled off the central California coast had also been infected with the 2009 pandemic H1N1 virus. This elephant seal exposure is the only other known pandemic H1N1 influenza infection in marine mammals, and similar to sea otters, it is unclear how the seals were exposed.
“Our new study identifies sea otters as another marine mammal species that is susceptible to influenza viruses and highlights the complex interspecies transmission of flu viruses in the marine environment,” said USGS scientist LeAnn White.
The 2009 H1N1 virus has spread globally among people since 2009 and was the predominant flu virus in circulation during the 2013-2014 flu season. This study is the first time that evidence of influenza infection has been detected in sea otters, although these viruses have previously been found in many different animals, including ducks, chickens, pigs, whales, horses and the elephant seals.
The study is published in the journal Emerging Infectious Diseases and is available online.
Sea otter sampling was performed by a collaboration of the USGS National Wildlife Health Center, USGS Alaska Science Center, USGS Western Ecological Research Center, Monterey Bay Aquarium and Seattle Aquarium.
The USGS and the Interior Department work with CDC and other state and federal partners on research related to zoonotic diseases – diseases that can be passed between animals and humans – to help provide an early warning to the agriculture, public health and wildlife communities, as well as to the public. For more information, please visit the USGS National Wildlife Health Center or CDC websites.
Media Advisory: Congressional Briefing on Nutrients and Pesticides in the Nation's Rivers and Streams
Ethan Alpern ( Phone: 703-648-4406 );
The Water Environment Federation (WEF) and the Northeast Midwest Institute invite you to a briefing by the USGS National Water-Quality Assessment Program (NAWQA) on findings of trends in nutrients and pesticides in the Nation's streams and rivers. The briefing will primarily focus on the Mississippi River Basin, which covers about 40% of the nation and represents a wide range of important climatic, agricultural, and urban influences that are present throughout the country.
As Congress debates federal activities and funding for water-quality protection and restoration efforts, it is critical to know how conditions are actually changing over time and to understand why changes have occurred. From NAWQA monitoring, we now know that nitrate loadings from the Mississippi River to the Gulf of Mexico increased 14 percent from 1980 to 2010 despite extensive efforts to improve and expand the use of urban and agricultural management practices during the period. Have governmental actions been effective or are other influences causing the changes?
The briefing will also include findings from the National Oceanic and Atmospheric Administration's (NOAA) efforts to assess the health of the Nation’s estuaries and will explain how information and findings from NAWQA’s monitoring and assessments contribute to their assessments and the protection of our estuaries.Who: Alan Vicory, Principal – Stantec Consulting & Chair – WEF Government Affairs Committee, Moderator
Lori Sprague, Coordinator – NAWQA Surface-Water Trends, U.S. Geological Survey
Suzanne Bricker, NOAA National Center for Coastal Ocean Science
When: Friday, April 11, 2014
10:00AM – 11:30AM
Where: Congressional Room South, CVC 217
Following presentations by the two speakers, there will be time for questions and discussion from the audience. This briefing is free and open to the public. Please RSVP to firstname.lastname@example.org. If you did not respond, you must show a picture ID. For more information, contact Ethan Alpern.
Catherine Puckett ( Phone: 352-377-2469 );
Dramatic distribution losses and a few major distribution gains are forecasted for southwestern bird and reptile species as the climate changes, according to just-published research by scientists with the U.S. Geological Survey, the University of New Mexico, and Northern Arizona University.
Overall, the study forecasted species distribution losses – that is, where species are able to live – of nearly half for all but one of the 5 reptile species they examined, including for the iconic chuckwalla. The threatened Sonoran (Morafka’s) desert tortoise, however, is projected to experience little to no habitat losses from climate change.
Breeding bird ranges exhibited greater expansions and contractions than did reptile species. For example, black-throated sparrows and gray vireos are projected to experience major gains in breeding habitat, but pygmy nuthatches, sage thrashers and Williamson sapsuckers are forecasted to experience large losses in breeding habitat, in some cases by as much as 80 percent. Thus, these three species might be expected to experience large future population declines.
The iconic pinyon jay is expected to experience from one-fourth to one-third loss in breeding habitat in the future, as its welfare is tied to declining pinyon pine habitat.
“Not surprisingly, whether a species is projected to be a winner or a loser depends primarily on its natural history and habitat needs and requirements,” said USGS scientist Charles van Riper III, the lead author on the study. “Land managers should be aware of these potential changes so that they can adjust their management practices accordingly.”
To conduct the study, scientists coupled existing global climate change models with newly developed species distribution models to estimate future losses and gains of 7 southwestern upland bird species and 5 reptile species. The study area focused on the Sonoran Desert and Colorado Plateau ecosystems within Arizona, western New Mexico, Utah, southwestern Colorado and southeastern California, but also included the rest of the Western United States. Focal wildlife species included resident and migratory birds and reptiles, which make up most of the vertebrate biodiversity in the region.
Temperatures in this region are projected to increase 6.3-7.2 F (3.5–4°C) within the next 60–90 years while precipitation is projected to decline by 5–20 percent.
“Changes of this magnitude may have profound effects on distribution and viability of many species,” noted Stephen T. Jackson, director of the Interior Department’s Southwest Climate Science Center. “Temperature matters a lot, biologically, in arid and semi-arid regions."
One very practical result of the project is a website with a series of range maps projecting the potential effects of climate change on bird and reptile distributions in the Western United States for three different time periods in the next 90 years. These predictions can help managers and policy makers better prioritize conservation effects, van Riper said.
“Wildlife resource managers need regionally specific information about climate change consequences so they better identify tools and strategies to conserve and sustain habitats in their region,” said Doug Beard, director of the USGS National Climate Change and Wildlife Science Center that supported the project. “Managers can use these results to help plan for ways to offset projected effects of climate change on these species.”
Detailed Bird Species Projections:
Overall: Black-throated sparrow and gray vireo are projected to experience major gains in breeding habitat. In contrast, pygmy nuthatches, sage thrashers and Williamson sapsuckers are projected to experience large losses in breeding habitat. Thus, these three species might be expected to experience large future population declines. (Note: species are linked to their in-depth report summaries.)
- Black-throated sparrow: breeding range projected to increase by 34-47 percent between 2010 and 2099.
- Gray vireo: breeding range projected to increase from 58-71 percent between 2010 and 2099.
- Virginia’s warbler: breeding range projected to decrease slightly, by 1.5-7 percent between 2010 and 2099.
- Sage thrasher: breeding range projected to decrease by 78 percent between 2010 and 2099.
- Pinyon jay: breeding range projected to decrease by 25-31 percent between 2010 and 2099.
- Pygmy nuthatch: breeding range projected to decrease by 75-81 percent between 2010 and 2099.
- Williamson’s sapsucker: breeding range projected to decrease by 73-78 percent between 2010-2099.
Overall: Future climate change will negatively affect the distributions of reptiles in the Western and Southwestern U.S. The one exception is the Sonoran desert tortoise, which is forecasted to expand, and, if a decrease happens, only by about one percent.
Reptiles can’t move as easily as birds nor can they regulate their body temperature, so they can only move minimally in response to changing climates. The authors found that the greater the projected distributional gain or loss in a reptile species was directly tied to the warmth of its current range. Thus, the less mobile reptiles will be more greatly affected by increasing temperatures.
- Plateau striped whiptail: range projected to decrease by 42 percent, assuming no dispersal, or by 17 percent, with unlimited dispersal, between 2010 and 2099.
- Arizona black rattlesnake: range projected to decrease between 32 and 46 percent between 2010 and 2099.
- Sonoran desert tortoise: The Sonoran (Morafka’s) desert tortoise is the only species of reptile for which projections do not include a decrease in suitable habitat by 2099 but only when unlimited dispersal is assumed. When assuming no dispersal, a slight one percent decrease is forecasted in the extent of suitable habitat.
- Common lesser earless lizard: ranged projected to decrease by 22-49 percent from 2010 to 2099.
- Common chuckwalla: projected ranges are likely to decrease by between 13 and 23 percent between 2010 and 2099.
The report, Projecting climate effects on birds and reptiles of the southwestern United States, is authored by Charles van Riper III, USGS; James Hatten, USGS; J. Tom Giermakowski, University of New Mexico; Jennifer A. Holmes and Matthew J. Johnson, Northern Arizona University; and others.
For more information about the USGS National Climate Change and Wildlife Science Center, please visit its website.
A Triptych of Urban Growth, NLCD 2001-2011
These three panels of cyclical data (2001, 2006, 2011) from the National Land Cover Database depict intervals of land cover change in the vicinity of Spring Valley, a suburb of Las Vegas, NV. NLCD 2011 (right panel) shows the expanding intensity of the developed impervious surface area (shades of red) during the 10-year period. Las Vegas continues to be one of the fastest growing metropolitan areas in the nation. (High resolution image 3.4 MB)
Just released, the latest edition of the nation’s most comprehensive look at land-surface conditions from coast to coast shows the extent of land cover types from forests to urban areas. The National Land Cover Database (NLCD 2011) is made available to the public by the U.S. Geological Survey and partners.
Dividing the lower 48 states into 9 billion geographic cells, the massive database provides consistent information about land conditions at regional to nationwide scales. Collected in repeated five-year cycles, NLCD data is used by resource managers and decision-makers to conduct ecosystem studies, determine spatial patterns of biodiversity, trace indications of climate change, and develop best practices in land management.
“America’s land and waters face unprecedented challenges from natural disasters, climate change, development pressures, and population growth,” said Anne Castle, Assistant Secretary of the Interior for Water and Science. “Prudently using our public lands and developing our energy potential, while protecting our natural resources at the same time, requires a keen appreciation of how the landscape is changing over time and the causes of those changes. The digital view that the National Land Cover Dataset affords us is sweeping, yet amazingly precise. It is one of the most important tools, for the Department of the Interior or any other land or water manager, in fostering an impartial perspective of landscape dynamics.”
Based on Landsat satellite imagery taken in 2011, NLCD 2011 describes the land cover of each 30-meter cell of land in the conterminous United States and identifies which ones have changed since the year 2006. Nearly six such cells — each 98 feet long and wide — would fit on a football field. Land cover is broadly defined as the biophysical pattern of natural vegetation, agriculture, and urban areas. It is shaped by both natural processes and human influences.
NLCD 2011 updates the previous database version, NLCD 2006. The NLCD program is designed to provide five-year cyclical updating of our nation's land cover, similar to the cyclical population updating done by the U.S. Census.
NLCD is constructed by the 10-member federal interagency Multi‑Resolution Land Characteristics Consortium (MRLC).
“The ongoing 20-year collaboration of the consortium is a model of cooperation among government entities,” said Matt Larsen, USGS associate director for climate and land use change. “Combining resources from MRLC member agencies to provide digital land cover for the Nation is the best kind of teamwork. It not only advances land change science, but it saves taxpayer money.”
The range and the spatial accuracy of NLCD have made it essential to thousands of expert users. The carefully calibrated data enables managers of public and private lands, urban planners, agricultural experts, and scientists with many different interests (for instance, climate, invasive species or hydrogeography) to identify critical characteristics of the land and patterns of land cover change, informing a variety of investigations from monitoring forests to modeling water runoff in urban areas.
NLCD 2011 products depict 16 classes of land cover in the lower 48 states, define the degree of surface imperviousness in urban areas (impervious surface extent — concrete, asphalt, etc. — serves as a marker for urban environmental quality), and quantify the amount of tree canopy cover (essential for applications dealing with wildfire, carbon sequestration, wildlife habitat, and biodiversity).
Additionally, NLCD editions from 2001 to 2011 have been integrated to provide a 10-year land cover change comparison for our nation at five year intervals. Having a decade of change information readily available for any location enables users to better understand the trajectory of land cover change patterns and provides specialists with critical information to advance the understanding of land cover change processes.
NLCD 2011 products will be also released for Alaska later this year. For more information on NLCD and to download NLCD data free of charge, visit the MLRC website.
HELENA, Mont. – A new report by the U.S. Geological Survey describes the extent and movement of contamination in the East Poplar oil field area in northeastern Montana. The contamination in shallow groundwater and the Poplar River is brine, which is saltier than seawater and is a byproduct as part of the process of extracting crude oil in the East Poplar oil field. The study determined likely source areas, brine plume extents, and movement of the plumes.
For more than half a century, millions of gallons of brine have been produced along with oil from the East Poplar oil field on the Fort Peck Indian Reservation. Until recently, the waste brine was placed in pits and ponds or injected into the ground through deep disposal wells and has made its way to the shallow groundwater and the Poplar River. Currently, the only approved method of brine disposal is to inject it deep into the ground.
When the brine mixes with the groundwater in the area, it often makes the water unsuitable for domestic purposes. Groundwater was previously the only available source of potable water to the area, and provided water for household wells and the city of Poplar’s public water-supply wells. Currently, treated water from the Missouri River about 20 miles upstream of the city of Poplar is piped to the city and nearby residents.
"There are many brine sources in the study area, resulting in multiple plumes. Some plumes remain in the groundwater for decades and have merged together, making it difficult to identify original sources," said Joanna Thamke, USGS hydrologist and lead author of the report. She continued, "this is important in development of water management practices, such as optimally locating wells in the future."
The USGS study, conducted in cooperation with the Fort Peck Tribe's' Office of Environmental Protection, shows that the brine contaminated groundwater is generally moving towards the southwest, eventually discharging into the Missouri River.
"This information will be used by the Fort Peck Tribes to direct future natural resource conservation efforts," said Deb Madison, Fort Peck Tribes' Environmental Programs Manager, who also added "the Fort Peck Tribes care deeply about these natural resources for today and for future generations."
Copies of "Delineation of Brine Contamination in and near the East Poplar Oil Field, Fort Peck Indian Reservation, Northeastern Montana, 2004–09" are available online.
Order of the Surveyor’s Chain, the first of several TNMCorps recognition awards, is conferred to volunteers who collect at least 25 points. (High resolution image) Theodolite Assemblage badge, currently the highest TNMCorps recognition award, is earned by collecting more than 2,000 points. (High resolution image)
This April marks the one year anniversary of the USGS's The National Map Corps (TNMCorps) transition from a small regional pilot project in the heart of Denver, Colo., into a very successful nation-wide project. During the past year, civilian volunteers in every state have increasingly provided accurate mapping data to the National Geospatial Program's publically available application called The National Map.
Using crowd-sourcing techniques, TNMCorps' Volunteered Geographic Information (VGI) project engages citizen scientists to collect manmade structures data including: schools, hospitals, post offices, police stations and other important public buildings.
By The Numbers:
Over the past year TNMCorps has achieved the following significant milestones:
- 1,422 – volunteers
- 42,009 - contributions (counts each person’s edit per single point)
- 33,698 - unique points edited (individual structures)
- 50,696 - total number of edits (the sum of all edits made by volunteers)
- 50 - number of states involved
- 18 - number of volunteers who have earned more than 500 points
- 4,691 - state with largest number of edited points; Colorado
"This project has proven that we can count on volunteers to provide quality information to be included in authoritative government databases", said Kari Craun, Director of the National Geospatial Technical Operations Center. "The people that have contributed their time are performing a community service by ensuring key structures data are available publically."
Becoming a volunteer for TNMCorps is easy; go to The National Map Corps project site to learn more and to sign up as a volunteer. If you have access to the Internet and are willing to dedicate some time editing map data, please consider participating. Participants can earn badges and public recognition by submitting a series of points.
While some familiarity with the area that a volunteer chooses is helpful, you do not have to live near a particular place to contribute. The tools on TNMCorps website, along with ancillary information available on the Internet, are generally sufficient to edit a distant area.
See for yourself how much fun participating can be. Go to The National Map Corps home page and give it a try.Status map showing the location and density of volunteer submitted structure edits. (High resolution image)
Sitkinak Island, Alaska — Ever since the great magnitude 9.2 earthquake shook Alaska 50 years ago today, scientists have suspected that the quake's rupture halted at the southwestern tip of Kodiak Island due to a natural barrier. However, recent research suggests some large quakes can punch through these obstacles, and have done so in the past, according to a new study published in Geophysical Research Letters, a journal of the American Geophysical Union.
U.S. Geological Survey scientists and researchers from partner institutions working on Sitkinak Island, 15 miles southwest of Kodiak Island, unearthed geologic records from the last 1,000 years of at least three large subduction ruptures – sudden dislocations in which one crustal plate lurches beneath another – that broke through the western edge of the 1964 Alaska earthquake. Among the new findings is the first geologic evidence of the great 1788 Alaska earthquake and tsunami, a seismic event previously known only from historical writings from Russian settlements in the region at the time.
During the 1964 Alaska earthquake, a sudden slip on the subduction megathrust extended from near Kayak Island in the east to the southwestern tip of Kodiak Island in the west, resulting in widespread ground shaking and a damaging tsunami.
To gather information on great earthquakes prior to 1964, the research team uncovered stratigraphic evidence of land-level change and tsunami inundation along the Alaska-Aleutian megathrust on Sitkinak Island. Hand-driven cores and tidal outcrops in a lagoon reveal five sharp changes in lithology and microfossils that record sudden upward and downward jerks during large earthquakes. Two of the changes correspond to the 1964 rupture and an earlier analog, while three sharp horizons mark ruptures that passed beneath Sitkinak Island, including the 1788 rupture.
"It's been proposed that the edge of the 1964 rupture acts as a long-lived and stable barrier limiting the size of great earthquakes," said Rich Briggs, lead author of the study and a USGS Research Geologist. "However, the geologic record suggests this isn't the case, and that some, if not most large ruptures break through. Future studies will aim to determine the sizes of these boundary-busting ruptures. Understanding this problem is important because hazard models depend on an accurate understanding of the locations and sizes of prehistoric earthquakes," Briggs added.
"The Sitkinak results demonstrate the crucial role that microfossils such as diatoms and foraminifera play in improving our understanding of great earthquake ruptures," said Simon Engelhart, a University of Rhode Island researcher and study coauthor. "They were the smoking gun that indicated both coseismic uplift and subsidence have occurred and, therefore, that Sitkinak Island is not a persistent rupture boundary."
Geologic evidence of a sudden uplift and an extensive sand sheet are consistent with Russian accounts of an earthquake and tsunami in 1788, but prior to this study no geologic evidence of this great event had been found.
"The 1788 rupture had important consequences for Kodiak Island because it resulted in evacuation of the Russian outpost at Three Saints Bay (near Old Harbor) and resettlement at the present site of Kodiak (city)," said Briggs. "Historical documents and our geologic observations suggest the 1788 earthquake ruptured offshore Kodiak and extended toward the Shumagin Islands rather than toward Anchorage."
Mapping prehistoric earthquakes in subduction zones requires a combination of approaches to indirectly capture evidence of massive undersea ruptures. Land-level changes and tsunami inundation—commonly recorded as raised or downdropped coasts and extensive sand sheets—can be revealed by mapping, coring, microfossil analysis, and a variety of dating techniques.
These findings have implications for hazard maps and tectonics studies, the study authors emphasized. An upcoming update of the USGS National Seismic Hazard Maps for Alaska will require a reevaluation of fault rupture histories.
"Understanding the ways faults have ruptured in the past is important because the paleoearthquake record gives us at least one set of scenarios to prepare for in the future," said Briggs. "Geologic information joins other critical data, such as seismological and geophysical observations, in helping us generate useful hazard models."
As a large pulse of water is being released into the former delta of the Colorado River along the U.S.-Mexico border, U.S. Geological Survey scientists are studying the effects on the environment as part of a historic, bi-national collaborative effort. The pulse flow and the need to study its effects were agreed to as part of the recently adopted Minute 319 (PDF) to the 1944 US-Mexico Water Treaty.
Results from this study will be used to assist and inform future bi-national cooperative efforts as both countries work together to protect resources on both sides of the border. The now-dry Colorado River delta was once a thriving wetland ecosystem where water and sediment delivered from the Colorado River watershed reached the Gulf of California. A century ago, the Colorado River delta was navigable by large boats. Today, upstream diversions and dams in both countries control the Colorado River’s flow, and little to no water is released into the channel downstream of Morelos Dam.
This engineered release of water is the culmination of years of negotiations led by the U.S. and Mexican Sections of the International Boundary and Water Commission in partnership with the Department of the Interior, in conjunction with the seven U.S. Colorado River Basin states, Mexican government agencies, and a wide array of municipal agencies, non-governmental organizations, and universities from both the U.S. and Mexico. The release of water began on March 23 and will continue for about eight weeks, with the rate of release peaking today, March 27. Over this period of time, 105,392 acre feet of water will be released, a volume that would fill about 52,000 Olympic sized swimming pools.
"This engineered pulse of water represents a truly unique scientific opportunity and is a wonderful example of a balanced approach to both conserve water and enhance fragile ecosystems," said Assistant Secretary of the Interior Anne Castle, who oversees the work of the USGS. "Linking scientists from Mexico and the United States will advance our understanding of environmental restoration opportunities along the Colorado River border and Delta,” she said. “While none of our agencies could take on this challenge alone, by partnering with experts in both countries, we are able to share information that will serve as a foundation for future cooperative efforts between our two nations."
"The USGS is honored to participate in this bi-national collaborative effort to understand the ecosystem effects of the pulse flow," said Suzette Kimball, Acting USGS Director. "These results will not only help inform decisions about potential future flows, but will also advance cooperative management efforts to improve the health of the delta region in both the U.S. and Mexico."
Minute 319 to the 1944 US-Mexico Water Treaty calls for studying the hydrologic and biologic effects of the pulse flow. Scientists from the USGS, the University of Arizona, the Universidad Autónoma de Baja California, and other institutions are working along a 24-mile long river segment of the Colorado River where one bank is in Arizona and the other is in Baja California, Mexico.
Research and monitoring will focus on understanding how the water moves through the Colorado River channel, how the pulse changes as it moves downstream and infiltrates through the streambed into the groundwater, evaluating sediment erosion and deposition, and patterns of new vegetation establishment. Studying these factors will help provide an understanding of why vegetation is able to thrive in some areas and not in others and information to inform decisions about future environmental flows. In addition, remote sensing technology will be used along the length of the Colorado River delta to complement on-the-ground observations.
Recognizing the challenges facing the Colorado River Basin, including a 14-year period of historic drought, Minute 319 was executed on Nov. 20, 2012. It provides for measures to enhance sharing of water supplies, permit Mexico to defer delivery of some of its allotted water in the United States, facilitate investment in Mexico’s water infrastructure, and measure the ecosystem effects of one experimental environmental pulse flow. The pulse flow is thus a critically important element of Minute 319—a component that both countries agreed to implement this spring.
Newly released US Topo maps for Utah now feature a new commercial road data provider. The latest highway, road and street data from HERE has been added to the 1,476 revised US Topo quadrangles for the state.
"HERE, a Nokia business, is proud to provide fresh, robust and comprehensive map content to the State of Utah and the US Topo Maps program," said Roy Kolstad, VP Sales Enterprise Americas, HERE. "We are excited for users to experience the benefits HERE brings with our more than 25 years of experience in cartography, drawing on more than 80,000 sources of data."
The new maps also include Public Land Survey System (PLSS). These data are added to the growing list of states west of the Mississippi River. PLSS is a way of subdividing and describing land in the United States. All lands in the public domain are subject to subdivision by this rectangular system of surveys, which is regulated by the U.S. Department of the Interior. Other selected states will begin getting PLSS map data during the next respective revision cycle.
The new design for US Topo maps improves readability of maps for online and printed use, while retaining the look and feel of the traditional USGS topographic map. Map symbols are easy to read when the digital aerial photograph layer imagery is turned on.
Other re-design enhancements and new features:
- New shaded relief layer for enhanced view of the terrain
- Military installation boundaries, post offices and cemeteries
- New road classification
- A slight screening (transparency) has been applied to some features to enhance visibility of multiple competing layers
- New PDF legend attachment
- Metadata formatted to support multiple browsers
US Topo maps are created from geographic datasets in The National Map, and deliver visible content such as high-resolution aerial photography, which was not available on older paper-based topographic maps. The new US Topo maps provide modern technical advantages that support wider and faster public distribution and on-screen geographic analysis tools for users.
The new digital topographic maps are PDF documents with geospatial extensions (GeoPDF®) image software format and may be viewed using Adobe Reader, available as a no-cost download.
US Topo maps are updated every three years. The initial round of the 48 conterminous state coverage was completed in September of 2012. Hawaii and Puerto Rico maps have recently been added. More than 400 new US Topo maps for Alaska have been added to the USGS Map Locator & Downloader, but will take several years to complete the vast state.
To download US Topo maps: http://nationalmap.gov/ustopo/March 2014 US Topo map of the Moab, Utah area, 1:24,000 scale. Orthoimage layer is turned on, contour and woodland layers turned off. (Larger image) 1885 historical USGS map of the Moab, Utah area, 1:250,000 scale.. (Larger image)
BOISE — The practice of emergency post-fire seeding in sagebrush landscapes of the Great Basin, which was meant to stabilize soils, has not resulted in restored habitats that would be used by greater sage-grouse according to U.S. Geological Survey and U.S. Forest Service researchers who published their results today in the journal Ecosphere.
The new study examined the habitat that was present 8-20 years after the seeding projects occurred. These aerial or rangeland drill seeding projects did not always include sagebrush seeds and were not intended to restore wildlife habitat, but instead were designed to mitigate the effects of fire on soil and vegetation. Yet they provide an opportunity to reverse habitat degradation for sage-grouse, a species being considered for protection under the Endangered Species Act.
Scientists first characterized which habitats and landscapes sage-grouse use throughout the Great Basin. Then they examined areas that had burned and were subsequently seeded with rangeland plant species between 1990 and 2003. To link the two phases of the study, the authors assessed whether vegetation conditions in rehabilitated areas were similar to the habitats used by sage-grouse.
The authors found that sage-grouse tend to use areas with a mixture of dwarf sagebrush and Wyoming big sagebrush, native grasses, minimal human development, and minimal non-native plants. This information will help land managers prioritize areas for protection from disturbance or areas for future sage-grouse specific restoration efforts.
"When we compared these vegetation and landscape conditions to those of post-wildfire rehabilitation sites, we found that the probability of sage-grouse using treated areas was low and not very different from burned areas that had not been treated," said USGS ecologist Robert Arkle, the lead author of the publication.This is sagebrush burning at Hart Mountain National Antelope Refuge in association with a management project located 65 miles northeast of Lakeview, OR.
Burned areas, whether treated or not, generally lacked shrubs even after 20 years, and in low elevation areas especially, non-native plants like cheatgrass were often too prevalent for burned sites to be used as sage-grouse habitat. This is important because it means that for at least 20 years following wildfire, burned areas of the Great Basin are not likely to be used by sage-grouse, regardless of emergency stabilization treatment. With this kind of time lag, a substantial amount of sage-grouse habitat is lost each year to wildfire, while gaining relatively little through natural plant succession or emergency stabilization treatments.
Published guidelines about what constitutes sage-grouse habitat also provided criteria for comparison to what the scientists observed in the seeded sites. Seeded areas met habitat guideline criteria for native grasses about half of the time, but the majority of seeding projects did not meet sagebrush or forb guideline criteria.
Some individual seeding projects did result in higher quality habitat and the authors evaluated the environmental conditions shared by these sites to determine where post-fire rehabilitation is more likely to benefit sage-grouse. Seeding projects that were most effective tended to occur in cool, moderately moist climates and also depended on post-treatment precipitation and surrounding landscape conditions.
"This is part of a growing body of science demonstrating how difficult it is to rehabilitate sagebrush landscapes once native vegetation is lost through wildfire," said USGS ecologist David Pilliod, who co-authored the publication. "Restoration in the Great Basin is a huge challenge for land managers not only because of difficulties associated with reducing non-native plants and establishing natives, but also because of the rate at which landscapes with sagebrush and other native vegetation are lost. These habitat losses can have negative consequences for sage-grouse and other wildlife that depend on sagebrush."
The study found that even relatively small amounts of non-native plants and human development were both forms of habitat loss that affected whether sage-grouse would use particular locations.
Although these projects did not specifically target sage-grouse, they are important sage-grouse conservation opportunities, according to Arkle. This is because wildfires burn about one million acres each year in the Great Basin and 97 percent of the acres treated by these projects are in historic sage-grouse habitat.
This research was conducted in collaboration with the Bureau of Land Management and the Joint Fire Science Project. Funding was provided by the U.S. Geological Survey, the Bureau of Land Management, and the U.S. Forest Service. The study, Quantifying restoration effectiveness using multi-scale habitat models- implications for sage-grouse in the Great Basin, published in Ecosphere is an offshoot of a larger effort to assess ecological outcomes of emergency stabilization and rehabilitation projects conducted by federal land managers in the Great Basin.
ANCHORAGE, Alaska — Why does the 1964 Great Alaska Earthquake Matter 50 Years Later? Scientific experts will talk about a half-century of scientific and monitoring advances triggered by the 1964 events.
The 1964 earthquake occurred at a pivotal time in the history of plate tectonics theory, giving scientists a context to understand the hazards of megathrust earthquakes, and more importantly, it led to the creation of modern national programs to reduce risk from earthquakes and tsunamis.
Press conference on the 50th anniversary of the 1964 Great Alaska Earthquake and Tsunami — the science behind the earthquake and tsunami, what we learned from the events, and how we are better prepared today for similar natural hazards.
Peter Haeussler, Research Geologist and Alaska Coordinator for Earthquake Hazards, U.S. Geological Survey
Paul Whitmore, Director, NOAA National Tsunami Warning Center
Michael West, State Seismologist, Director, Alaska Earthquake Center, University of Alaska Fairbanks
Tuesday, March 25, 2014, 10:00 a.m. Alaska time
An audio bridge will be available for remote participation: 703-648-4848, (or toll free 855-547-8255) Security code: 77680#
Resources for the news media, including links to videos, photos, and a fact sheet are available on the USGS "1964 Great Alaska Earthquake and Tsunami" website.
A. Arrows show generalized movements of birds in particular flyways. Red arrows show general movements in the East Atlantic Flyway and yellow arrows show general movement in the North American Atlantic Flyway. Most birds use only portions of the flyways, which are determined mostly by species and by origin of breeding populations.
B. Red dots show the locations of where birds were sampled in the study. Reykjavik is shown for reference. Samples from some locations (Breiðafjörður and Selfoss) were obtained over a larger area than shown because samples were provided by hunters and fishermen within the region. (High resolution image)
The North Atlantic region is a newly discovered important pathway for avian influenza to move between Europe and North America, according to a U.S. Geological Survey report published today.
USGS scientists and Icelandic partners found avian flu viruses from North America and Europe in migratory birds in Iceland, demonstrating that the North Atlantic is as significant as the North Pacific in being a melting pot for birds and avian flu. A great number of wild birds from Europe and North America congregate and mix in Iceland's wetlands during migration, where infected birds could transmit avian flu viruses to healthy birds from either location.
By crossing the Atlantic Ocean this way, avian flu viruses from Europe could eventually be transported to the United States. This commingling could also lead to the evolution of new influenza viruses. These findings are critical for proper surveillance and monitoring of flu viruses, including the H5N1 avian influenza that can infect humans.
"None of the avian flu viruses found in our study are considered harmful to humans," said Robert Dusek, USGS scientist and lead author of the study. "However, the results suggest that Iceland is an important location for the study of avian flu and is worthy of special attention and monitoring."
The study also highlighted the new finding that gulls play an important role in moving avian flu viruses across the North Atlantic.
During the spring and autumn of 2010 and autumn of 2011, the USGS researchers and Icelandic partners collected avian influenza viruses from gulls and waterfowl in southwest and west Iceland (see map). By studying the virus’ genomes — an organism’s hereditary information — the researchers found that some viruses came from Eurasia and some originated in North America. They also found viruses with mixed American-Eurasian lineages.
"For the first time, avian influenza viruses from both Eurasia and North America were documented at the same location and time," said Jeffrey Hall, USGS co-author and principal investigator on this study. "Viruses are continually evolving, and this mixing of viral strains sets the stage for new types of avian flu to develop."
The partners on the new study include the Southwest Iceland Nature Research Institute, the University of Iceland's Snaefellsnes Research Centre, the University of Minnesota and the J. Craig Venter Institute. This study was funded by the USGS and the National Institute of Health’s Centers of Excellence for Influenza Research and Surveillance.
The report was published today in the journal PLOS ONE and is available online.
For more information on avian influenza research, please visit the USGS National Wildlife Health Center website.
Ethan Alpern ( Phone: 703-648-4406 ); Julio Betancourt ( Phone: 703-648-5840 );
In a finding authors are coining an "unintentional rewilding," scientists identified a cave dung deposit as belonging to bighorn sheep that became extinct on a desert island sometime between the 6th and the 20th century.
The unintentional rewilding occurred when in 1975 wildlife biologists introduced 16 female and 4 male bighorn sheep to Tiburón Island, the largest island in the Gulf of California. Today, the population numbers more than 500 individuals.
A team from the University of California-Riverside, the U.S. Geological Survey, Oregon State University, and East Tennessee State University discuss this non-native rewilding on Tiburón Island, located in the Gulf of California, in this week's PLOS ONE. Ben Wilder, Ph.D. Candidate of UC-Riverside and the lead author of the study, accidentally discovered the 1500-1600 year-old, urine-cemented dung mat on the floor of a small cave in the Sierra Kunkaak, a rugged mountain range of the eastern side of the island.
After comparing the pellets with an extensive collection of dung for both living and extinct herbivores, researchers determined that bighorn sheep formed the dung mat. The ancient sequences exactly matched DNA sequences from modern desert bighorn sheep, and differed substantially from other large herbivores that might have been present.
Until this discovery, there was no knowledge on whether or not bighorn sheep had previously occurred on the island.
"It's a very clear result," said Clinton Epps, a co-author and a conservation geneticist at Oregon State University. "Furthermore, the sequences are not identical to the modern bighorn populations on Tiburón Island - so we are confident that the sequences do not derive from modern use of the cave by introduced bighorn sheep."
Julio Betancourt, a USGS paleoecologist and co-author of the study, has previously collaborated with geneticists to extract and sequence ancient DNA from cave deposits. Betancourt thinks that, in the future, "molecular caving will become more than an afterthought in arid lands paleoecology."
Michael Hofreiter of the University of Potsdam, a leading authority in ancient DNA research and editor of the paper, notes that, "Given the ongoing progress in paleogenomics and DNA sequencing, it will soon be possible to sequence full genomes from samples like the one recovered from Tiburón island, compare those to genomes from various extant populations and thereby identify the population that is most suitable for reintroduction in a certain area."
The goal of the 1975 re-introduction was use a safe site to foster a large, breeding population that could be used in restocking the mainland, where historic land use decimated native bighorn sheep populations. A controversial aspect of the Tiburón experiment is that it introduced what was then presumed to be a non-native herbivore into a fragile island ecosystem with a unique desert flora.
Wilder said he hopes that these findings will trigger more systematic studies of recent colonization and extinction events throughout these islands and elsewhere to help guide conservation efforts.
The study, "Local extinction and unintentional rewilding of bighorn sheep (Ovis canadensis) on a desert island," was authored by Benjamin T. Wilder, Julio L. Betancourt, Clinton W. Epps; others, and was published this week in PLOS One.
Everglades National Park, Fla.— Invasive Burmese pythons in South Florida are able to find their way home even when moved far away from their capture locations, a finding that has implications for the spread of the species.
A multi-organizational team of scientists found that when six Burmese pythons were relocated 13-22 miles from their capture locations, the snakes headed straight back home, navigating to within 3 miles of their original capture locations in Everglades National Park.
"Previous studies have shown that many snakes lack the ability to home, yet this study provides evidence that Burmese pythons are capable of homing after they have been displaced --- and they are able to do so at a scale previously undocumented for any snake species," said Shannon Pittman, lead author of the study and a postdoctoral fellow at Davidson College in North Carolina. "Understanding this large-scale navigational ability is critical to understanding the ability of Burmese pythons to expand their geographic range," Pittman added.
To find your way home requires a map sense on the part of the animal, which allows the animal to determine its position in relation to a goal; and a compass sense, which requires access to a reliable compass to maintain orientation toward the goal. The relocated snakes moved faster and straighter than snakes that were not relocated, demonstrating that Burmese pythons have navigational map and compass senses.
The relocated snakes also appeared to use local cues from their release site to determine their position relative to home. Potential cues underlying the map sense in pythons may be olfactory or magnetic that change predictably through space. The compass aspect of their navigational ability could be accomplished through the use of magnetic, celestial, olfactory or polarized light cues, all of which generate a reliable compass sense.
"The snakes maintained their oriented movement over the course of a relatively long time, between 94 and 296 days," said Kristen Hart, a USGS researcher and study coauthor. "This indicates that not only do pythons keep their long-term movement goal in mind, but also that they were highly motivated to get back home."
These findings have implications for management and conservation of the species, the study authors emphasized. Animals that are adept at navigating and homing are better able to exploit resources that are relatively far away, widely spaced or seasonally variable. These abilities also reduce risks associated with searching potentially hostile or unfamiliar areas because the dispersing snakes can always return to a safe location.
"Understanding navigation in invasive species improves the ability to control populations and limit dispersion," said Hart. "For example, the fine-tuned navigational capacity that the pythons exhibited may lower their risk when they move to and explore new areas."
This research is useful for resource managers because it has implications for python movement behavior at the edges of the invasion front where there is a need for containment, Pittman said.
"Invasive exotic reptiles continue to challenge agencies charged with protecting the health of south Florida ecosystems," said Everglades National Park Superintendent Dan Kimball. "Continued research like this on the invasive exotic Burmese python is critical so that we can make better informed management decisions and move closer to containment of this species that has adapted to this environment."
The invasive Burmese python is an apex predator in the Everglades that became established in Florida several decades ago. The largest snakes removed from the Everglades have exceeded 18 feet and 150 pounds. Snakes of this size are capable of ingesting large prey like adult deer and alligators.
"Homing of invasive Burmese pythons is South Florida: evidence for map and compass senses in snakes" by S.E. Pittman, K.M. Hart, M.S. Cherkiss, R.W. Snow, I. Fujisaki, B.J. Smith, F.J. Mazzotti, and M.E. Dorcas, is published in the journal Biology Letters. The study can be accessed online.
Last year, the estimated value of mineral production in the U.S. was $74.3 billion, a slight decrease from $75.8 billion in 2012. According to the U.S. Geological Survey’s annual Mineral Commodity Summaries 2014 report, the 2013 decrease follows three consecutive years of increases. Net U.S. exports of mineral raw materials and old scrap contributed an additional $15.8 billion to the U.S. economy.
"To put this in context, the $90.1 billion value of combined mined, exported, and recycled raw materials is more than five times greater than the 2013 combined net revenues of Internet titans: Amazon, Facebook, Google, and Yahoo. This illustrates the fundamental importance of mineral resources to the nation’s economy, technology, and national security," said Larry Meinert, USGS Mineral Resources Program Coordinator.
Minerals remain fundamental to the U.S. economy, contributing to the real gross domestic product at several levels, including mining, processing, and manufacturing finished products. The U.S. continues to rely on foreign sources for raw and processed mineral materials.
This annual USGS report is the original source of mineral production data for the world. It includes statistics on about 90 mineral commodities essential to the U.S. economy and national security, and addresses events, trends, and issues in the domestic and international minerals industries.
"Decision makers and policy makers in the private and public sectors rely on the Mineral Commodity Summaries and other USGS minerals information publications as unbiased sources of information to make business decisions and national policy," said Michael J. Magyar, Acting Director of the USGS National Minerals Information Center.
Production increased for most industrial mineral commodities mined in the U.S., and prices remained stable. Industrial mineral commodities include cement, clays, crushed stone, phosphate rock, salt, sand and gravel, and soda ash, which are used in industrial applications such as building and road construction and chemical manufacturing.
Production of most metals was relatively unchanged compared with that of 2012, but reduced prices resulted in an overall reduction in the value of metals produced. Domestically produced metals include copper, gold, iron, molybdenum, and zinc, which are used in a wide variety of products including consumer goods, electronic devices, industrial equipment, and transportation systems.
Domestic raw materials and domestically recycled materials were used to process mineral materials worth $665 billion. These mineral materials, including aluminum, brick, copper, fertilizers, and steel, and net imports of processed materials (worth about $24 billion) were, in turn, consumed by downstream industries with a value added of an estimated $2.4 trillion in 2013.
The construction industry began to show signs of improvement in 2012, and those trends continued in 2013, with increased production and consumption of cement, construction sand and gravel, crushed stone, and gypsum, mineral commodities that are used almost exclusively in construction.
Mine production of 14 mineral commodities was worth more than $1 billion each in the U.S. in 2013. These were, in decreasing order of value, crushed stone, gold, copper, cement, construction sand and gravel, iron ore (shipped), molybdenum concentrates, phosphate rock, industrial sand and gravel, lime, soda ash, salt, zinc, and clays (all types).
In 2013, 12 states each produced more than $2 billion worth of nonfuel mineral commodities. These states were, in descending order of value—Nevada, Arizona, Minnesota, Florida, Texas, Alaska, Utah, California, Wyoming, Missouri, Michigan, and Colorado. The mineral production of these states accounted for 64% of the U.S. total output value.
Government agencies and the industrial and financial sectors use data from this and other USGS minerals reports to prepare legislation and key economic reports and to evaluate national defense mineral requirements. USGS produces more detailed and updated data throughout the year in the USGS Minerals Yearbook and Mineral Industry Surveys.
The USGS Mineral Resources Program delivers unbiased science and information to understand mineral resource potential, production, consumption, and their interaction with the environment. The USGS National Minerals Information Center collects, analyzes, and disseminates current information on the supply of and the demand for minerals and materials in the U.S. and about 180 other countries.
The USGS report "Mineral Commodity Summaries 2014" is available online. Hardcopies will be available later in the year from the Government Printing Office, Superintendent of Documents. For ordering information, please call (202) 512-1800 or (866) 512-1800 or go online.
For more information on this report and individual mineral commodities, please visit the USGS National Minerals Information Center.