USGS Newsroom

Pika Populations Affected by Climate in the Great Basin

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 13 Mar 2013 12:38:40 EDT

BOZEMAN, Mont. – Climate factors such as snowpack and precipitation are playing an increasingly important role in the abundance of American pikas in the Great Basin, according to a continuing ecological study by the U.S. Geological Survey, University of Montana and Montana State University.

Pikas are diminutive herbivores that resemble hamsters and live exclusively in rocky slopes across many mountain ranges in the American West. This study contributes to a legacy of more than 100 years of pika studies in the Great Basin – the internally draining area between the Sierra Nevada and Rocky Mountains. In the Basin, researchers are recording pikas' shrinking distribution, and finding their population sizes increasingly responsive to climate change but difficult to predict.

The size of pika populations did not correlate with the extent of habitat present in either the 1990s or 2000s, according to the researchers, who were revisiting sites where pikas were first recorded in historical surveys going back more than a century. Given how strongly pikas are tied to their rocky habitat, this current finding challenges the assumption that just because physically suitable habitat is present – even in remote, apparently relatively undisturbed locations – that pikas will continue to occupy those habitats.

Researchers also investigated the potential impact of climate stress on pika density. The results suggested that climate change may be adding another filter for suitability of habitats. "Precipitation during June-September and amount of snowpack appeared to be the most powerful predictors of pika density in the 2000s," said USGS research ecologist Erik Beever, lead author of the study. "Precipitation appears to be important because it can influence the amount of food available for pikas in the summer, and an insulating snowpack can minimize exposure of pikas to extreme cold-stress," Beever said. Across the western United States, snow-water equivalents have been declining and temperatures have been rising since the 1930s.

Perhaps the most surprising result was the direct relationship between population size and probability of future extinctions of local pika populations. "When we consider extinction risk, we intuitively think that smaller populations are at the highest risk," Beever said. "We looked at the record of extinctions up to 1999, and calculated the risk of future site-level extinction. We were surprised to find that sites with higher extinction risk in 1999 had larger populations in 2003-2008," he said. The authors suggest that this non-intuitive result may reflect changes in the rules governing abundance between the 1990s and 2000s surveys (perhaps ushered in by recent climate change), lags in response of abundance to extinction risk, or other mechanisms.

Researchers revisited sites of historical (1898-1956) pika records and performed surveys of pika abundance from 1994 to 1999 and from 2003 to 2008 to understand the factors predicting pika population sizes.

The study, "Understanding relationships among abundance, extinction and climate at ecoregional scales," to be published in the journal Ecology, is available online.

Lake Mead Aquatic-Science Research Documents Substantial Improvements in Ecosystem

OC_Web@usgs.gov (Office of Communications and Publishing) — Tue, 29 Jan 2013 17:41:09 EDT

Additional Partnerships: University of Nevada, Reno and University of Nevada, Las Vegas

Additional Contacts: Dan Balduini, USFWS, 702-515-5480, daniel_balduini@fws.gov and Peter Soeth, Reclamation, 303-445-3615, psoeth@usbr.gov

LAS VEGAS, Nev. — Lake Mead National Recreation Area's water quality is good, the sport fish populations are sufficient, and the lakes provide important habitat for an increasing number of birds. This positive trend is documented in a new report published today that leads to a better understanding of the natural resources of Lake Mead and Lake Mohave, and the issues that may affect natural resource management of Lake Mead NRA.

"While the Lake Mead ecosystem is generally healthy and robust, the minor problems documented in the report are all being addressed by the appropriate agencies, and are showing substantial improvement since the mid 1990's," said U.S. Geological Survey hydrologist, Michael Rosen, the lead scientist for the report. "This is thanks to proactive enhancements to wastewater treatment facilities for the Las Vegas Metropolitan area, the installation of wetlands in Las Vegas Wash, and the treatment of legacy pollutants from industrial areas near Las Vegas Wash."

Lake Mead provides significant benefits that have contributed to the modern development of the southwestern United States. The lake provides important aquatic habitat for a wide variety of wildlife including endangered species, and a diversity of world-class water-based recreational opportunities for more than 8 million visitors annually. It supplies critical storage of water supplies for more than 25 million people in three western states (California, Arizona, and Nevada). Storage within Lake Mead supplies drinking water and provides for the generation of hydropower to deliver electricity for major cities including Las Vegas, Phoenix, Los Angeles, Tucson, and San Diego. It also provides water for irrigation of more than 2.5 million acres (almost 4000 square miles or more than twice the size of the state of Delaware) of croplands.

Major findings detailed in the report include the following:

Basic water-quality parameters are within good ranges of Nevada and Arizona standards and EPA lake criteria. Potential problems with nutrient balance, algae, and dissolved oxygen can occur at times and in some areas of Lake Mead. The Lake Mead-wide scope of monitoring provides a solid baseline to characterize water quality now and in the future.
Legacy contaminants are declining due to regulations and mitigation efforts in Las Vegas Wash. Emerging contaminants, including endocrine disrupting compounds, are present in low concentrations. While emerging contaminants, such as pharmaceuticals, personal care products, or plasticizers have been documented to cause a number of health effects to individual fish, they are not seen at concentrations currently known to pose a threat to human health. In comparison to other reservoirs studied by the U.S. Environmental Protection Agency, Lake Mead is well within the highest or 'good' category for recreation and aquatic health.
Lake Mead and Lake Mohave continue to provide habitat conditions that support a rich diversity of species within the water, along shorelines, and in adjacent drainage areas, including organisms that are both native and non-native to the Colorado River drainage.
Sport fish populations appear stable and have reached a balance with reservoir operations over the past 20 years and are sufficient to support important recreational fishing opportunities. Native fish populations within Lake Mohave are declining, but the small native fish populations in Lake Mead are, stable without any artificial replenishment.
Lake Mead and Lake Mohave provide important migration and wintering habitat for birds. Trends include increasing numbers of wintering bald eagles and nesting peregrine falcons. Lake Mead water-level fluctuations have produced a variety of shorebird habitats, but songbird habitats are limited. Although some contaminants have been documented in birds and eggs in Las Vegas Wash, mitigation efforts are making a positive change.
Invasive quagga mussels have become the dominant lake-bottom organism and are a significant threat to the ecosystems of Lake Mead and Lake Mohave because they have potential to alter water quality and food-web dynamics. Although they increase water clarity, they can degrade recreational settings.
Climate models developed for the Colorado River watershed indicate a high probability for longer periods of reduced snowpack and therefore water availability for the Lake Mead in the future. Federal, state and local agencies, and individuals and organizations interested the future of the water supply and demand imbalance are working together to examine strategies to mitigate future conditions.

The report was prepared cooperatively by the U.S. Geological Survey, National Park Service, U.S. Fish and Wildlife Service, Bureau of Reclamation, Nevada Department of Wildlife, Southern Nevada Water Authority, BIO-WEST, University of Nevada, Reno, and University of Nevada, Las Vegas.

The full report, USGS Circular 1381, "A synthesis of aquatic science for management of Lakes Mead and Mohave," is available online.

Note to editors: B-roll available from USGS upon request.

Lidar Yields New Insights into Desert Fire Ecologies

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 28 Nov 2012 12:00:00 EDT

MENLO PARK, Calif. —New insights into the differences between fire ecologies of the Chihuahuan and Mojave Deserts in the southwestern United States are coming through the use of terrestrial Light Detection and Ranging, or lidar, technology. Studies by the U.S. Geological Survey show that while fire is detrimental to some areas of the desert, it is beneficial to others.

“Just as some ecosystems require periodic flooding for their rebirth and health maintenance, this new lidar information shows that some grasslands depend on periodic fires to give the native vegetation a competitive advantage," said USGS Director Marcia McNutt. "This new science is important in informing management because the natural human tendency is to suppress hazardous events like floods and fires.”

Scientists used terrestrial or ground-based lidar to study the soil and vegetation characteristics of two desert ecosystems. In the Chihuahuan Desert of New Mexico, historically a grassland, they confirmed that fire can prevent the incursion of invasive shrub vegetation, while in parts of the Mojave Desert that are historically covered in shrubs, they showed that fire can harm the fertile shrub mounds, leading to loss of vegetation and increased erosion.

“Fire can hinder conservation in areas naturally covered by shrubland, but may help remove shrubs and restore native vegetation in areas naturally covered by grasslands,” said USGS geographer Chris Soulard. “These research studies are collaborative efforts aimed at building a long-term, ecosystem specific understanding of the ecological effects of fire and the possible beneficial roles of fire in land management.”

Terrestrial lidar uses lasers typically mounted on tripods to generate high-resolution, three-dimensional models of the sampled area. The level of detail is higher than in aerial lidar, aerial photography, or satellite imaging and T-lidar scanning instruments are easier and faster to deploy.

The Chihuahuan Desert study area was in the Sevilleta National Wildlife Refuge of New Mexico, managed by the U.S. Fish and Wildlife Service. In spring 2007, sample plots were burned, clipped, or left undisturbed, and in the summer of 2011 terrestrial lidar was used to measure soil and vegetation characteristics. In their burn experiments, a team of scientists including Joel Sankey of the USGS and Sujith Ravi with the University of Arizona, observed shrub-vegetated areas disappearing and the formation of numerous, small grass-dominated areas indicating the progression of the system towards a state more characteristic of the native grasslands found in this area.

Woody plant encroachment can degrade desert grasslands, leading to areas of shrub vegetation surrounded by patches of nutrient-depleted bare soil. “The results of our Chihuahuan Desert study suggest that fire (prescribed, accidental, or natural) might reverse the shrub encroachment process, if it occurs in the early stages of vegetation shift,” said Sankey, a USGS research physical scientist. “This may inform the use and role of fire in the context of changing disturbance regimes and climate.”

The Mojave Desert project study area was in Grand Canyon-Parashant National Monument, Arizona. Prescribed fires were set in 1998, and in 2009 T-lidar data was collected on both burned and unburned sample plots by a team of USGS scientists. The recovering vegetation in the burned sites had smaller dimensions, which exposed the soil mounds to erosion. Consequently, post-fire erosion led to the reduction in the soil mound volume and surface roughness in these sites. Soil surface changes alter physical and nutrient conditions that promote shrub health, and lead to decreased chances of seed germination and decreased ability to retain water.

For more information, see the full journal articles. The Chihuahuan Desert study, “Quantifying soil surface change in degraded drylands: shrub encroachment and effects of fire and vegetation removal in a desert grassland”, was published in the Journal of Geophysical Research and is authored by J.B. Sankey, S. Ravi, C.S.A. Wallace, R.H. Webb, and T.E. Huxman. The Mojave Desert study, “The role of fire on soil mounds and surface roughness in the Mojave Desert” was published in the journal Earth Surface Processes and Landforms and is authored by Chris Soulard, Todd Esque, Dave Bedford, and Sandra Bond.

Volcanism in the American Southwest

OC_Web@usgs.gov (Office of Communications and Publishing) — Fri, 19 Oct 2012 13:30:00 EDT

FLAGSTAFF, Ariz. — Experts in volcano hazards and public safety have started a conversation about volcanoes in the southwestern United States, and how best to prepare for future activity. Prior to this meeting, emergency response planning for volcanic unrest in the region had received little attention by federal or state agencies.

Though volcanic eruptions are comparatively rare in the American Southwest, the states of Arizona, Colorado, New Mexico, Nevada, and Utah host geologically-recent volcanic eruption deposits and are vulnerable to future volcanic activity. Compared with other parts of the western U.S., comparatively little research has been focused on this area, and eruption probabilities are poorly understood.

“A volcanic eruption in the American southwest is an example of a low-probability, but high-impact event for which we should be prepared to respond,” said USGS Director Marcia McNutt. “No one wants to be exchanging business cards during an emergency, and thus a small investment in advance planning could pay off in personal relationships and coordination between scientists and first responders.”

"The goal of the conference is to increase awareness of volcanism and vulnerabilities in the American Southwest, and to begin coordination among volcano scientists, land managers, and emergency responders regarding future volcanic activity," said Dr. Jacob Lowenstern, one of the organizers of the conference, and the U.S. Geological Survey Scientist-In-Charge of the Yellowstone Volcano Observatory. "This is the first time these federal, state, and local agencies have met to discuss their roles, responsibilities, and resources, should an eruption occur."

The "Volcanism in the American Southwest" conference on Oct. 18-19 in Flagstaff, Ariz. was organized by the USGS, Northern Arizona University, University at Buffalo, and New Mexico Bureau of Geology and Mineral Resources, the meeting included interdisciplinary talks, posters, and panel discussions, providing an opportunity for volcanologists, land managers, and emergency responders to meet, converse, and begin to plan protocols for any future volcanic activity.

More information about the meeting, including presentation abstracts, is online.

Modeling Predicts Excessive Nitrate and Arsenic in Southwestern U.S. Aquifers

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 27 Sep 2012 16:00:00 EDT

Modeling results from the U.S. Geological Survey indicate that groundwater in basin-fill aquifers (sediment-filled valleys) beneath about 2.4 percent of the area in the southwestern U.S. may equal or exceed the drinking-water standard for nitrate, and groundwater beneath about 43 percent of the area may equal or exceed the standard for arsenic. These aquifers are an important resource, providing about 40 percent of the water used in that region. While several compounds occur in groundwater from these aquifers, nitrate and arsenic are among those most frequently found to exceed drinking-water standards established by the U.S. Environmental Protection Agency for protection of human health.

While public water supplies are treated to ensure that water reaching the tap of households meets federal requirements, there are no such requirements for private supplies. The results highlight the importance of private well owners testing and potentially treating their water. All of the contaminants identified in the aquifers can be reduced or eliminated through a variety of treatments.

"The alluvial basins of the American Southwest can provide a valuable water resource to growing populations who often lack other sources of fresh water," said USGS Director Marcia McNutt. "However, the results of this modeling study raise a cautionary flag for private well owners of the need to test water to ensure its safety and to take action to remediate any contamination that is found."

Areas where nitrate concentrations are predicted to equal or exceed the EPA drinking-water standard (10 milligrams per liter as nitrogen) occur in several basins in central Arizona near Phoenix; the southern part of California’s Central Valley; as well as several basins near Los Angeles along the southern coast; and the San Luis Valley of south-central Colorado.

Much of the area where arsenic concentrations are predicted to equal or exceed the drinking-water standard (10 micrograms per liter) is within several basins in parts of southwestern Arizona, southeastern California, western Nevada, and western Utah. Most of the area with predicted high arsenic concentrations is in sparsely populated rangeland, whereas most of the area with predicted high nitrate concentrations occurs where agricultural or urban communities are located.

The USGS National Water-Quality Assessment Program study, which included parts of Arizona, California, Colorado, Nevada, New Mexico, and Utah, applied a statistical modeling approach that extrapolates nitrate and arsenic occurrence from areas where concentrations are known, to other areas where such data are unavailable. The extrapolation is based on nitrate and arsenic analyses from well-water samples collected from 1980 to 2010, and a wide variety of hydrologic, geologic, climatic, soil, land use, water use, agricultural, and biotic conditions that local-scale geochemical studies have found to be relevant to nitrate or arsenic occurrence in groundwater.

Results from this study are available online.

Jill Rolland is Western Fisheries Research Center�s New Leader

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 24 Sep 2012 13:30:04 EDT

SEATTLE — The U.S. Geological Survey has named fish pathologist Dr. Jill Rolland the director of its ‪Western Fisheries Research Center (WFRC), headquartered in Seattle.

Since 2010, Rolland has been the director of the U.S. Department of Agriculture’s National Center for Animal Health Programs. From 2007 to 2010, she was the center’s assistant director for aquaculture, swine, equine and poultry health programs. She joined the USDA in 2002 as a fish biologist in the aquatic animal health program of the USDA’s Animal and Plant Health Inspection Service and became the program manager in 2005. Rolland began her new job at the WFRC on Sept. 10.

Jill Roland, Director, Western Fisheries Research Center (WFRC)

Rolland previously worked part-time at the WFRC and also taught part-time at Shoreline Community College, north of Seattle.

She earned her M.S. and Sc.D. in fish health from the University of Bergen in Norway and her B.S. in Fisheries/Aquaculture from the University of Washington.

“The appointment of Dr. Rolland to head our Western Fisheries Research Center is certain to continue the excellent tradition of cooperation between the USGS and USDA in fisheries health,” said USGS Director Marcia McNutt. “We are so pleased to welcome her back to the USGS in this leadership role to help us find solutions for healthy and abundant fish, healthy ecosystems, and healthy aquatic environments.”

The WFRC is one of 18 USGS science centers engaged in biological research on critical natural resource issues facing the nation. Research in WFRC’s six laboratories -- in Seattle; on Marrowstone Island and in the Columbia River Gorge, Wash., in Klamath Falls and Newport, Ore., and Reno, Nev. -- focuses on the environmental factors responsible for the creation, maintenance, and regulation of fish populations and their interactions in aquatic communities and ecosystems.

Natural resources of particular interest to the center include Pacific salmon; western trout, char, and resident riverine fishes; desert and inland fishes; and aquatic ecosystems including Puget Sound and the Columbia and Klamath River basins. Current research includes studying fish populations and ecosystems and salmon-wildlife interactions within the Elwha River Restoration Project, the largest dam removal project in U.S. history.

President Obama Honors Justin Hagerty for Helping to Explain the Formation and Evolution of the Moon

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 23 Jul 2012 15:15:58 EDT

USGS scientist Justin Hagerty was one of the 2012 recipients of the President's Early Career Award for Science and Engineering.

Dr. Justin Hagerty, a research geologist with the U.S. Geological Survey, was named one of President Obama's recipients of the Presidential Early Career Award for Scientists and Engineers, the highest honor bestowed by the United States government on science and engineering professionals in the early stages of their independent research careers.

Hagerty, an accomplished research geologist, studied the formation of the Moon and discovered the answer to a long-standing riddle of the Moon’s early history. His use of chemical tracers and remote sensing data allowed him to discover why certain elements are concentrated in some areas and not in others, a puzzle which had complicated the primary theory of how the Moon came to be.

"Discoveries in science and technology not only strengthen our economy, they inspire us as a people." President Obama said. "The impressive accomplishments of today’s awardees so early in their careers promise even greater advances in the years ahead."

The Presidential early career awards embody the high priority the Obama Administration places on producing outstanding scientists and engineers to advance the Nation's goals, tackle grand challenges, and contribute to the American economy.

"It is a tremendous and highly unexpected honor to receive such a prestigious award, and I am very grateful for all of the opportunities and support I have received throughout my career, particularly at the USGS," said Hagerty. "Because my research is based on combining data from a variety of disciplines, I have had the opportunity to work with many talented colleagues from varied backgrounds who have helped to shape my career."

"The USGS traces its program in astrogeology back nearly 50 years to the Nation's need to train astronauts destined for the Moon in lunar geology," said USGS Director Marcia McNutt. "The President's recognition of Justin Hagerty for his contributions to explaining long-standing paradoxes concerning the early evolution of the only extraterrestrial body to which man has yet ventured is one of the highest honors yet for this exceptional program."

The commonly accepted theory of how the Moon formed hypothesized that a Mars-sized planetary body collided with a proto-Earth. This massive collision led to the creation of the Moon and the Earth as we know them today. However, one major issue with this theory is that, based on models of such a collision, there should be an even, global distribution of certain elements like potassium, uranium, thorium, and the rare earth elements.

Instead, these elements are mostly concentrated in the hemisphere of the Moon that faces the Earth. To learn why, Hagerty studied expanses of geologic materials on the far side of the Moon called basalt ponds.

Lunar basalts are much like basalts on the Earth in that they are a product of melting the mantle, which is the area between the crust and the core of the Moon. Given this information, it is possible to use compositional data derived from the basalts to learn about the composition of the lunar interior. Much focus has been placed on basalts on the near side of the Moon, primarily because the Apollo missions only returned samples from that part of the lunar surface. However, it is now possible (and necessary) to use a combination of lunar sample analysis and remote sensing observations to investigate materials on the lunar far side, thus giving us a global context.

His research shows that another major impact event on the Moon, now known as the South Pole-Aitken Basin, greatly disrupted the early formation of the Moon, resulting in the migration and eventual concentration of these elements to the side of the Moon that faces the Earth.

"I have also used the methodology of combining sample and remote sensing data to investigate other unresolved issues in lunar science," added Hagerty. "In particular, I worked with several colleagues to establish the existence of silicic volcanic domes on the Moon."

It was previously thought that silicic volcanoes, which erupt silica-rich materials like quartz, instead of the more common basalts, were not possible on the Moon. To explain the origin of these features, Hagerty developed a new model for how such features could be produced in the unique lunar environment. This model demonstrates that silicic lunar volcanoes can be produced quite easily and likely comprise a much larger portion of the lunar crust than was thought. These results have important implications for crustal formation models and calculations of the bulk composition of the Moon.

Hagerty's results are critical to understanding the early history and evolution of our closest celestial neighbor.

"Prior to graduate school, I, like many people, had assumed that the Moon was a dull, lifeless body," said Hagerty. "However, after having the opportunity to learn from experts in lunar science and to examine lunar sample and remote sensing data myself, it quickly became apparent that the Moon is an extraordinary planetary body and that we have only scratched the surface of truly understanding how the Moon formed and evolved. To have an opportunity to play a role in shaping our cumulative knowledge of the Moon is a humbling experience."

Hagerty is currently the curator of the USGS Meteor Crater Sample Collection, as well as the Chair of NASA's Regional Planetary Image Facility Network.

The USGS Meteor Crater Sample Collection is an ongoing project funded by NASA that analyzes drill samples from Meteor Crater and makes the samples available to the planetary science community. The NASA Regional Planetary Image Facility Network is an international system of planetary data libraries that maintains a wide range of data products from NASA planetary missions including photographs, maps, films, engineering plans, and historical documents and artifacts. The overriding mission of the Network is to make these materials available to the public.

Hagerty earned his Ph.D. in Earth and Planetary Sciences from the University of New Mexico, Albuquerque, in 2004; his M.S. in Earth and Planetary Sciences from the University of New Mexico, Albuquerque, in 2001, and his B.S. in Earth and Planetary Sciences, with Honors, from the University of New Mexico, Albuquerque, in 1998. He was a post-doctoral fellow at the Los Alamos National Laboratory from 2004-2007, where he studied lunar geochemistry.

Hagerty came to the USGS in 2007, joining the USGS Astrogeology Science Center in Flagstaff, Arizona. He has been the principal investigator on eight NASA studies and collaborated on an additional four studies. His research has examined not only lunar geochemistry, but also lunar mapping, asteroid mapping, and impact cratering.

Hagerty’s official citation from the Award reads:

Department of Interior/US Geological Survey
Justin J. Hagerty
U.S. Geological Survey

For cutting edge research fusing remote-sensing data of the Moon with laboratory measurements to establish a new coherent model of the lunar crust and mantle and for leadership and service contributions for an international network of 17 Regional Planetary Image Facilities.

The Presidential Early Career Awards for Scientists and Engineers was established by President Clinton in 1996, and are coordinated by the Office of Science and Technology Policy within the Executive Office of the President. Awardees are selected for their pursuit of innovative research at the frontiers of science and technology and their commitment to community service as demonstrated through scientific leadership, public education, or community outreach.

From Pikas to Plague, Climate Change and Wind Energy

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 16 Jul 2012 9:00:00 EDT

USGS Science at the Society for Conservation Biology

More than 800 people are expected to attend the first North America Congress for Conservation Biology from July 15-18, 2012, in Oakland, Calif. The theme of this year's conference is “Bridging the Gap: Connecting People, Nature, and Climate.” This conference provides a forum for presenting and discussing new research and developments in conservation science, practices and challenges.

Fighting Plague with a Peanut Butter-Flavored Vaccine: Prairie dogs and highly endangered black-footed ferret populations in North America are quite susceptible to sylvatic plague, an often deadly, non-native disease of people and wildlife. Currently, wildlife managers contain the disease by dusting prairie dog burrows with an insecticide that can kill disease-carrying fleas, but this is labor-intensive and costly. As an alternative, USGS researchers and colleagues at University of Wisconsin have developed a new oral vaccine, flavored with peanut butter, which can be administered orally through baits. Laboratory tests showed that the oral vaccine protects prairie dogs against plague; tests in some wild prairie dog populations begin this year. If the vaccine is effective in the wild, it could be used in selected prairie dog populations to decrease the occurrence of plague and help in the recovery of black-footed ferrets. Ultimately, a successful vaccine could help stabilize wildlife populations in grassland ecosystems and may benefit public health, since this bacterium is also responsible for plague in people. This presentation, Sylvatic Plague Vaccine: A New Tool for Conservation of Threatened and Endangered Species, will occur in Room JRB 1 on July 16 at 11 a.m. For more information, contact Tonie Rocke, trocke@usgs.gov, 608-270-2451.

Shorebird, Duck, Food Enough? With loss of natural wetlands, wintering shorebirds and diving ducks have become increasingly dependent on managed wetlands. Yet studies are limited about food availability in managed coastal estuaries, such as the ponds in the San Francisco Bay’s South Bay Salt Pond Restoration Project. USGS researchers and colleagues will discuss their surveys of invertebrate prey density in the pond bottoms. They will discuss whether there is enough food to support the 45,000 diving ducks and 108,000 shorebirds that depend on this area in winter, and whether pond management could increase available energy. This presentation, Effects of Wetland Management on Carrying Capacity of Duck and Shorebird Benthivores in a Coastal Estuary, will occur in Room JBR 1 & 2 on July 16. Contact Arriana Brand, 707-562-2002, arriana_brand@usgs.gov, or John Takekawa, 707-562-2000, john_takekawa@usgs.gov.

Climate Change and Pliable Pikas? Animals that live in mountain ecosystems are sensitive to small changes in climate and are often exposed to frequent swings in temperature and wind speed, poorly developed soils and generally harsher conditions than animals living at lower elevations. The American pika is a small, mountain-dwelling, hamster-like animal that lives in rocky talus slopes and lava flows typically in mountain ecosystems throughout the western United States. Recently, researchers concluded that the rate of local pika extinction in the hydrographic Great Basin over the last 10 years has increased to about five times faster than averaged during the 20th century. Analogously, the lowest elevation that pikas are occupying moved upslope 11 times faster during that decade than during the 20^th century, suggesting that what constitutes suitable habitat is now shrinking more rapidly. A USGS researcher will present findings that illustrate how hydrological variables – such as snow-water equivalent and growing-season precipitation – are important predictors of pika abundance for this region. In addition, the scientist will show how pika behavioral flexibility – such as use of non-traditional habitats and drinking free water – can, in some cases, allow pikas to live on the edges of their climatic niche. This presentation, Temporally shifting determinants of distribution and abundance of American pikas, and behavioral plasticity ‘softening’ ecological-niche boundaries,” will occur in Symposium 8 (Grand Ballroom, Rooms 1 & 2) on July 16 at 3 p.m. The presentation leads off the symposium, Pikas in Peril? Distribution, Population Trends and Resilience of the American Pika. Contact Erik Beever, ebeever@usgs.gov, 406-994-7670.

Restoring South San Francisco Bay Wetlands in the Face of Sea Level Rise: The South Bay Salt Pond Restoration Project is attempting to restore ecosystem services such as flood control, wildlife habitat and outdoor recreation to some 15,000 acres of wetlands in San Francisco Bay and Silicon Valley. But to do so requires a long-term adaptive management plan with rigorous monitoring and scientific support. Project Executive Director John Bourgeois of the California State Coastal Conservancy will discuss how public and private research partners -- including USGS -- are clarifying the uncertainties involved in such a major restoration project -- such as sea level rise resiliency, sufficient sediment flow for marsh accretion, and disturbance of legacy mercury. This presentation, Restoring South San Francisco Bay Wetlands in the Face of Sea Level Rise will occur in Room JBR 1&2 on July 16 at 3:45 p.m. Contact Laura Valoppi, USGS biologist and Restoration Project's Research Coordinator, laura_valoppi@usgs.gov, 916-704-6198.

From Conservation Reserve Land to Ag Land: Substantial Losses for Amphibians: High commodity prices for agricultural crops, especially for biofuel feedstocks, is rapidly resulting in the conversion of USDA’s Conservation Reserve Program (CRP) lands to agricultural production in the northern Great Plains. USGS scientists used an ecosystem services model to evaluate the potential effects of this land-use change on amphibians, which have been declining worldwide, primarily because of land-use change. Their scenarios focused on CRP conversion rates of 10, 25, 50, 75 and 100 percent in different parts of North Dakota, South Dakota, Minnesota and Iowa. They then compared present amphibian habitat quality and quantity under the projected conversion rates. They found that if all CRP lands were converted to cropland, one-fourth to over one-third of all amphibian habitat could be lost, which could have devastating effects on amphibian populations in the northern Great Plains. The scientists noted that even at the lowest conversion rate of 10 percent, habitat losses and potential effects on amphibians were still substantial. This presentation, Effects of Land-Use/Land-Cover Change on Amphibian Habitat in the Northern Great Plains, will take place in Room 208 on July 17 at 8:30 a.m. Contact David Mushet, dmushet@usgs.gov, 701-253-5558.

Developing Solutions to Reduce Harmful Effects of Wind Energy on Bats: U.S. Geological Survey researchers and their U.S. Fish and Wildlife Service colleagues are working together to help provide solutions for reducing harmful effects of wind turbines on bats. This joint project is prioritizing research topics such as predicting mortality of bats by wind turbines and using bat life-history information to develop ways to reduce the number of bat deaths. Projects funded through this collaborative process will focus on addressing the most critical research needs to ensure that wind energy development can grow while minimizing costs to wildlife. This presentation, Bats and Wind Energy: State of Knowledge and Research Priorities for USFWS and USGS, will take place in Room JBR 1 & 2 on July 17 from at 12:30 p.m. It is one of eight presentations in a symposium entitled Cultivating a Role for Wildlife Conservation in Energy Development. Contact Laura Ellison, ellisonl@usgs.gov, 970-226-9494.

Renewable Energy and Terrestrial Wildlife: Large areas of the Desert Southwest have been developed for utility-scale renewable energy projects, including both wind and solar facilities. The Desert Southwest is also an area of exceptional biodiversity, providing habitat for many sensitive terrestrial species, including the federally protected desert tortoise. USGS scientists and their colleagues reviewed the scientific literature on the effects of utility-scale energy development (wind and solar) and operation on terrestrial, non-flying wildlife. They found that while there is a growing and comparatively large body of information on the effects of wind energy on birds and bats, little information exists in the peer-reviewed scientific literature to evaluate the effects of wind or solar facilities on terrestrial wildlife in the world, including in offshore environments. Potential effects of such facilities include habitat modification and fragmentation, as well as effects from noise, dust, and roads and traffic. Before and after studies of utility-scale renewable energy sites are needed to adequately assess their effects on terrestrial wildlife and to develop methods to address those effects. This presentation, Terrestrial Wildlife Conservation and Renewable Energy Development in the Desert Southwest United States: A Review, will occur in Room JBR 1 & 2 on July 17 at 11:30 a.m. It is one of eight presentations in a symposium entitled Cultivating a Role for Wildlife Conservation in Energy Development. Contact Jeff Lovich, jeffrey_lovich@usgs.gov, 928-556-7358.

Wildlife Response to Fire: Climate Change and Corridor Conservation in Southern California: In southern California, wildfires are expected to become more frequent as climate change occurs, so understanding how increased fire will impact wildlife habitats and behavior is critical for effective resource planning. Researchers analyzed GPS tracking data on bobcats, coyotes and mountain lions in southern California to understand how mammalian carnivores respond to burned landscapes, and whether the home ranges and movement patterns of these species changed with wildfire and urban development. Researchers from San Diego State University, USGS, Colorado State University, and University of California, Davis, participated in this study. This presentation, Corridor Conservation in Southern California under Climate Change: Understanding Wildlife Response to Burned Landscapes, will occur in Room OCC 210/211 on July 17 at 3:45 p.m. Contact Erin Boydston, eboydston@usgs.gov, 805-370-2362, or Lisa Lyren at llyren@usgs.gov, 760-931-1101.

San Francisco Bay: Water and Climate Change Projections, 2000-2100: Just-completed climate change scenarios for the years 2000-2100 in the San Francisco Bay project an increased variability in the bay’s water runoff, recharge and stream discharge, as well as a shifting of the seasonal timing of the bay’s water cycles. The four scenarios, completed by USGS researchers, used IPCC (Intergovernmental Panel on Climate Change) projections of future climate changes to create a regional water balance model. For both drier and wetter scenarios, seasonal warming amplified the climatic water deficit, a measure of drought stress on soils and vegetation. This state-of-the-art climate science should help managers plan for the future. This presentation, Ensemble Hydrologic Modeling for the Next Century: Implications for San Francisco Bay Area Natural Resources, will take place in Room GBR 1&2 on July 18 at 8:50 a.m. Contact A.L. Flint at aflint@usgs.gov, 916-278-3221.

California Climate Change and Landscape Connectivity: By analyzing the present and expected future climate conditions of protected areas within California, USGS researchers were able to identify the stability of those areas with respect to climate change; they then identified where increased landscape connectivity might help offset the negative effects of climate change. Because changing climate conditions will not affect all areas in California equally, researchers examined which protected areas would likely benefit most from expanded landscape connectivity via corridors. This information can help resource managers and policy-makers prioritize decisions about the most effective ways to mitigate the effects of climate change with limited resources. This presentation, California Climate Change and Landscape Connectivity, will occur in ROOM GBR 1&2 on July 18 at 11 a.m. Contact Jason Kreitler, jkreitler@usgs.gov, 208-426-5217.

LiDAR Technology Reveals Faults Near Lake Tahoe

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 23 May 2012 14:33:42 EDT

CARNELIAN BAY, Calif. — Results of a new U.S. Geological Survey study conclude that faults west of Lake Tahoe, Calif., referred to as the Tahoe-Sierra frontal fault zone, pose a substantial increase in the seismic hazard assessment for the Lake Tahoe region of California and Nevada, and could potentially generate earthquakes with magnitudes ranging from 6.3 to 6.9. A close association of landslide deposits and active faults also suggests that there is an earthquake-induced landslide hazard along the steep fault-formed range front west of Lake Tahoe.

Using a new high-resolution imaging technology, known as bare-earth airborne LiDAR (Light Detection And Ranging), combined with field observations and modern geochronology, USGS scientists, and their colleagues from the University of Nevada, Reno; the University of California, Berkeley; and the U.S. Army Corps of Engineers, have confirmed the existence of previously suspected faults. LiDAR imagery allows scientists to "see" through dense forest cover and recognize earthquake faults that are not detectable with conventional aerial photography.

"This study is yet one more stunning example of how the availability of LiDAR information to precisely and accurately map the shape of the solid Earth surface beneath vegetation is revolutionizing the geosciences," said USGS Director Marcia McNutt. "From investigations of geologic hazards to calculations of carbon stored in the forest canopy to simply making the most accurate maps possible, LiDAR returns its investment many times over."

Motion on the faults has offset linear moraines (the boulders, cobbles, gravel, and sand deposited by an advancing glacier) providing a record of tectonic deformation since the moraines were deposited. The authors developed new three-dimensional techniques to measure the amount of tectonic displacement of moraine crests caused by repeated earthquakes. Dating of the moraines from the last two glaciations in the Tahoe basin, around 21 thousand and 70 thousand years ago, allowed the study authors to calculate the rates of tectonic displacement.

"Although the Tahoe-Sierra frontal fault zone has long been recognized as forming the tectonic boundary between the Sierra Nevada to the west, and the Basin and Range Province to the east, its level of activity and hence seismic hazard was not fully recognized because dense vegetation obscured the surface expressions of the faults," said USGS scientist and lead author, James Howle. "Using the new LiDAR technology has improved and clarified previous field mapping, has provided visualization of the surface expressions of the faults, and has allowed for accurate measurement of the amount of motion that has occurred on the faults. The results of the study demonstrate that the Tahoe-Sierra frontal fault zone is an important seismic source for the region."

An abstract of the paper, "Airborne LiDAR analysis and geochronology of faulted glacial moraines in the Tahoe-Sierra frontal fault zone reveal substantial seismic hazards in the Lake Tahoe region, California-Nevada USA," published in the "Geological Society of America Bulletin" is available online. Contact GSA for a copy of the full article.

A video is available online showing a visual example of how airborne LiDAR (Light D etection And Ranging) imagery penetrates dense forest cover to reveal an active fault line not detectable with conventional aerial photography.

A Big Day for Science: Citizens Have Contributed One Million Observations to Top Nature Database

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 3 May 2012 9:00:00 EDT

RESTON, Va. — Thanks to citizen-scientists around the country, the USA National Phenology Network hit a major milestone this week by reaching its one millionth nature observation.

The millionth observation was done by Lucille Tower, a citizen-scientist in Portland, Ore., who entered a record about seeing maple vines flowering. Her data, like all of the entries, came in through USA-NPN’s online observation program, Nature's Notebook, which engages more than 4,000 volunteers across the country to observe and record phenology – the timing of the recurring life events of plants and animals such as when cherry trees or lilacs blossom, when robins build their nests, when salmon swim upstream to spawn or when leaves turn colors in the fall.

Each record not only represents a single data point — the status of a specific life stage of an individual plant or animal on one day – but also benefits both science and society by helping researchers understand how plants and animals are responding to climate change and, in turn, how those responses are affecting people and ecological systems.

"My dream is that through the wonders of modern technology and the National Phenology Network we could turn the more than six billion people on the planet into components of our scientific observing system," said USGS Director Marcia McNutt. "We could make giant leaps in science education, improve the spatial and temporal coverage of the planet, lower the cost of scientific data collection, and all while making ordinary citizens feel a part of the scientific process."

Jake Weltzin, a U.S. Geological Survey scientist and the executive director of USA-NPN, concurs. "Hitting the one millionth observation is exciting because researchers and decision-makers need more information to understand and respond to our rapidly changing planet. More information means better-informed decisions that ensure the continued vitality of our natural areas that we all depend on and enjoy."

For example, said Weltzin, the data in Nature's Notebook are already being used to benefit society, including the development of more accurate indicators of spring, forecasting the onset of allergy seasons or the chances of western wildfires, managing wildlife and invasive plants, and setting goals for habitat restoration. Ultimately, such information can be used for better managing water resources, wildlife and ecosystem management, and even help farmers and ranchers across the nation.

Changes in phenology are among the most sensitive biological indicators of global change. Across the world, many springtime events are occurring earlier — and fall events happening later — than in the past. These changes are happening quickly for some species and more slowly, or not at all, for others, altering relationships and processes that have been dynamically stable for thousands of years. Some wildlife —like caribou and butterflies — are becoming mismatched from their plant food resources, which are responding differently. Migrations for some birds are changing too, as they can now overwinter instead of moving south for the winter, or as they fly north more quickly to keep pace with an advancing front of spring flowering.

Because of this, said Weltzin, scientists need more and better information about the pace and pattern of nature — locally to nationally — to answer important scientific and societal questions, and to build the tools and models needed to help people understand and adapt to the changes.

"So much of our improved understanding about global environmental changes is driven by varied and valuable sources of information that include networks of citizen-scientists," said John Wingfield, National Science Foundation’s assistant director for biological sciences. "The public at large has played an important role collecting observations and data for a hundred years and more. Knowledge and data gained from their work will continue to have a lasting effect on how we understand regularly recurring biological phenomena for hundreds of plant and animal species and contribute to the policy arena."

Gwen Lundburg in Seattle is one citizen-scientist who has contributed hundreds of entries into Nature’s Notebook. "Just noticing small changes like tiny purple lilac buds suddenly turning green has taught me to look more closely at my plants," Lundburg said. "I see things in my garden I never saw before."

With the help of citizen-scientist volunteers, working in concert with professionals, the USA-NPN, which was established in 2007, collects, stores and freely shares phenological data on more than 800 species of plants and animals. The Nature’s Notebook observing program has been in operation since 2009. The coordinating office of the organization is located at 1955 E. 6^th St., Tucson, Ariz., 85721. For more information, visit the USA National Phenology Network, or contact Jake Weltzin at 520-626-3821 or jweltzin@usgs.gov.

Earbones Accurately Record a Fish�s Life Travels

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 30 Apr 2012 9:07:33 EDT

Studying the earbones of trout can reveal their lifetime movements in a large river system, according to a study released in the Canadian Journal of Fisheries and Aquatic Sciences.

Scientists correlated the natural variation in strontium isotopes found in stream waters against those recorded in otoliths (earbones) of westslope cutthroat trout to examine fish movements during their lifetime.

This study was the first to show that the use of isotopes in water and earbones accurately assesses movement of trout wholly within a freshwater system. The research was conducted by scientists from the U.S. Geological Survey’s Northern Rocky Mountain Science Center, Woods Hole Oceanographic Institution, Montana State University, and Montana Fish, Wildlife & Parks.

"It worked so well! The values in the water matched those in the otoliths, which grow like rings in a tree," said Clint Muhlfeld, USGS scientist and lead author of the study. "As fish grow and move into new environments, the otoliths record that information and we matched that with stream statistics to reconstruct the entire life cycle of a fish."

The study provides a reliable method that compliments traditional fish tracking techniques. This research may allow biologists to investigate non-native species invasions, identify important populations, and quantify life histories of freshwater fishes in river networks.

"All life is literally a product of its chemical environment, and there is no more dramatic demonstration of that fact than the ability to retrace the life history of fish from the variations in the chemicals deposited in their ear bones as they grow and migrate through space and time," explained USGS Director Marcia McNutt. "As this technique has already proven its scientific value in understanding the movement of fish in the marine environment and those which migrate from freshwater streams to the ocean, it is truly an achievement that could inspire 'CSI'."

Westslope cutthroat trout are an important native fish species in western North America where their populations have declined because of factors including habitat destruction, fragmentation and non-native species. These fish make extensive migrations among spawning, growth and refuge habitats, yet conventional tracking techniques have not been able to unravel the extent of their movements. Knowing exactly what habitat the fish use during each life stage is an important component to understanding their ecology and, in turn, more effectively managing this important species.

"This approach could be very useful in understanding life history strategies and conservation needs of freshwater fishes worldwide," said Muhlfeld. "Biologists are typically limited to examining movements of fish at checkpoints throughout their lives or over small periods of time. This approach allows examination of a fish’s entire life with significant accuracy."

The study provides a reliable method that compliments traditional fish tracking techniques and may allow biologists to investigate non-native species invasions, identify important populations, and quantify life histories of freshwater fishes in river networks. The article, "Estimating westslope cutthroat trout (Oncorhynchus clarkii lewisi) movements in a river network using strontium isoscapes," can be viewed online.

More information about this study can be found on the USGS Northern Rocky Mountain Science Center website.

Say Hello to CalVO: USGS California Volcano Observatory Opens

OC_Web@usgs.gov (Office of Communications and Publishing) — Thu, 9 Feb 2012 12:00:00 EDT

“More than 500 volcanic vents have been identified in the State of California. At least 76 of these vents have erupted, some repeatedly, during the last 10,000 years. … Sooner or later, volcanoes in California will erupt again, and they could have serious impacts on the health and safety of the State's citizens as well as on its economy.” Miller, C. Dan, 1989, Potential Hazards from Future Volcanic Eruptions in California: U.S. Geological Survey Bulletin 1847, 17p.

MENLO PARK, Calif. — The U.S. Geological Survey announces the establishment of the USGS California Volcano Observatory, or CalVO, headquartered within existing USGS facilities in Menlo Park, Calif. Establishing CalVO will increase awareness of and resiliency to the volcano threats in California, many of which pose significant threats to the economy and well being of the state and its inhabitants.

"By uniting the research, monitoring, and hazard assessment for all of the volcanoes that pose a threat to the residents of California, CalVO will provide improved hazard information products to the public and decision makers alike," explained USGS director Marcia McNutt. "This realignment is part of the USGS's efforts to build the National Volcano Early Warning System, a prioritized modernization of USGS volcano monitoring enabled through the American Reinvestment and Recovery Act."

CalVO takes on responsibility for research, monitoring, and assessing hazards for all of the potentially active volcanoes in California and coordinating with local and State emergency managers to prepare for responding to renewed volcanic activity. Previously, the USGS Cascades Volcano Observatory in Vancouver, Wash was responsible for responding to volcanic unrest at some northern California volcanoes.

CalVO replaces the former Long Valley Observatory, established in 1982 to monitor the restless Long Valley Caldera and Mono-Inyo Craters region of California. The creation of CalVO will improve coordination with federal, state, and local emergency managers during volcanic crises, and create new opportunities for volcanic hazard awareness and preparedness. The realignment of USGS Volcano Observatories will further facilitate collaboration with federal and state partner agencies including the California Emergency Management Agency and the California Geological Survey.

"California has always led the nation in comprehensive planning for potential disasters. Having the USGS take the initiative to enhance their volcanic threat capabilities and, most importantly, improve planning and coordination with California's emergency managers is welcomed news. At the end of the day, the public expects us to plan for all hazards, and this is another great example," said Mike Dayton, Undersecretary of the California Emergency Management Agency.

"California is the most geologically diverse state in the nation. We are known for our earthquakes, landslides and flood hazards. But our nearly forgotten hazard is our volcanoes," said Dr. John Parrish, the State Geologist of California. "The California Geological Survey welcomes the new CalVO with its expanded scope and organization, and we look forward to its successful operations. The new CalVO will streamline our emergency response operations since CGS has offices at the USGS Menlo Park complex, and CalVO’s authority now encompasses all of California's volcanic provinces in one center."

In 2005, the USGS issued an assessment entitled "Volcanic Threat and Monitoring Capabilities in the United States" (USGS OFR 2005-1164). Volcanic threat rankings for U.S. volcanoes were derived from a combination of factors including age of the volcano, potential hazards (the destructive natural phenomena produced by a volcano), exposure (people and property at risk from the hazards), and current level of monitoring (real-time sensors in place to detect volcanic unrest).

The list of potentially threatening volcanoes on CalVO's watch list includes Mount Shasta, Medicine Lake Volcano, Clear Lake Volcanic Field, and Lassen Volcanic Center in northern California; Long Valley Caldera and Mono-Inyo Craters in east-central California; Salton Buttes, Coso Volcanic Field, and Ubehebe Craters in southern California; and Soda Lakes in central Nevada. CalVO's watch list is subject to change as new data on past eruptive activity becomes known, as volcanic unrest develops, as monitoring networks are upgraded, and/or as exposure factors change.

Under the Stafford Act, the USGS has the federal responsibility to issue timely and effective warnings of potential volcanic disasters. In addition to CalVO, the USGS operates four other volcano observatories. The Cascade Volcano Observatory oversees efforts at all potentially active volcanoes in Oregon, Washington, and Idaho. The Yellowstone Volcano Observatory is responsible for volcanoes in Montana, Wyoming, Colorado, Utah, New Mexico, and Arizona. The Alaska Volcano Observatory oversees Alaskan volcanoes and those within the Commonwealth of the Northern Mariana Islands. The oldest USGS volcano observatory, the Hawaiian Volcano Observatory, is responsible for the state of Hawaii and is celebrating its 100^th anniversary this year. All USGS volcano observatories share scientific expertise, administrative staff, and equipment.

For more information on the USGS Volcano Hazard Program visit http://volcanoes.usgs.gov/. See also USGS fact sheets: "The National Volcano Early Warning System (NVEWS)” FS-2006-3142 and "U.S. Geological Survey's Alert Notification System for Volcanic Activity," FS-2006-3139.

Visit the new CalVO website.

Dramatic Links Found Between Climate Change, Elk, Plants, and Birds

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 9 Jan 2012 11:30:00 EDT

Missoula, MT – Climate change in the form of reduced snowfall in mountains is causing powerful and cascading shifts in mountainous plant and bird communities through the increased ability of elk to stay at high elevations over winter and consume plants, according to a groundbreaking study in Nature Climate Change.

The U.S. Geological Survey and University of Montana study not only showed that the abundance of deciduous trees and their associated songbirds in mountainous Arizona have declined over the last 22 years as snowpack has declined, but it also experimentally demonstrated that declining snowfall indirectly affects plants and birds by enabling more winter browsing by elk. Increased winter browsing by elk results in trickle-down ecological effects such as lowering the quality of habitat for songbirds.

The authors, USGS Montana Cooperative Wildlife Research Unit scientist Thomas Martin and University of Montana scientist John Maron, mimicked the effects of more snow on limiting the ability of elk to browse on plants by excluding the animals from large, fenced areas. They compared bird and plant communities in these exclusion areas with nearby similar areas where elk had access, and found that, over the six years of the study, multi-decadal declines in plant and songbird populations were reversed in the areas where elk were prohibited from browsing.

"This study illustrates that profound impacts of climate change on ecosystems arise over a time span of but two decades through unexplored feedbacks," explained USGS director Marcia McNutt. "The significance lies in the fact that humans and our economy are at the end of the same chain of cascading consequences."

The study demonstrates a classic ecological cascade, added Martin. For example, he said, from an elk’s perspective, less snow means an increased ability to freely browse on woody plants in winter in areas where they would not be inclined to forage in previous times due to high snowpack. Increased overwinter browsing led to a decline in deciduous trees, which reduced the number of birds that chose the habitat and increased predation on nests of those birds that did choose the habitat.

"This study demonstrates that the indirect effects of climate on plant communities may be just as important as the effects of climate-change-induced mismatches between migrating birds and food abundance because plants, including trees, provide the habitat birds need to survive," Martin said.

The study, Climate impacts on bird and plant communities from altered animal-plant interactions, was published online on Jan. 8 in the journal Nature Climate Change.

New USGS Science: Groundwater Study of the Eastern Great Basin

OC_Web@usgs.gov (Office of Communications and Publishing) — Wed, 28 Sep 2011 13:50:00 EDT

The report can be found online.

Groundwater pumping, which has been increasing since the 1940s, now accounts for about one third of the estimated annual flow from the aquifers of the eastern Great Basin. In parts of this region, groundwater pumping exceeds the rate of natural discharge, leading to land subsidence and declines in water levels and spring flow.

U.S. Geological Survey scientists recently published a report examining groundwater recharge (replenishment) and discharge for the eastern Great Basin. The study examined 110,000 square miles across Utah, Nevada, California and Idaho, and the report covers groundwater conditions from Death Valley in the southwest to Cache Valley in the northeast.

"Groundwater resources are not only a critical part of present water supplies in this area, but are likely to increase in importance in the future because the region is facing population growth and limited surface water supplies," said Kevin Dennehy, coordinator for the USGS Groundwater Resources Program. "The results of the study have the potential to aid state and local agencies to better manage their future water supplies."

"This USGS publication evaluates the groundwater resources of the eastern Great Basin, a part of the United States that is predominantly desert yet is under considerable pressure for continued development," said Hugh Hurlow, a senior scientist with the Utah Geological Survey. "The USGS used the most advanced techniques available and the report thoroughly explains the data sources and methods of analysis. This work improves understanding at a regional scale, providing an essential template for more local, focused analyses."

The primary uses for groundwater withdrawals in this area are for irrigation, municipal purposes and industrial water. There are several large water development projects currently being considered for transporting groundwater from rural valleys to urban areas in order to supply cities with municipal water for future growth.

USGS scientists developed a new three-dimensional model of the area's geology, providing insights into how carbonate (bedrock) and alluvial (loose sediment) aquifers are connected over much of the eastern Great Basin. Hydrologic data from hundreds of previous reports were compiled to map directions of groundwater flow and develop a regional groundwater budget (analysis of recharge and discharge) of the aquifer system.

USGS Scientific Investigations Report 2010-5193, "Conceptual Model of the Great Basin Carbonate and Alluvial Aquifer System," can be viewed online. The report consists of multiple chapters documenting various aspects of the aquifer system, along with plates, appendices, auxiliary files and GIS data sets.

This report is a product from the four-year study funded by the USGS Groundwater Resources Program as part of a national assessment of groundwater availability.

New Film -- Lake of the Sky: USGS Tahoe Basin Science

OC_Web@usgs.gov (Office of Communications and Publishing) — Mon, 15 Aug 2011 15:14:32 EDT

MENLO PARK, Calif. — On Aug. 16, the USGS will debut a new film, “Lake of the Sky: USGS Tahoe Basin Science,” on scientific research in the Lake Tahoe Basin at the 15th Annual Lake Tahoe Summit "Stewardship and Sustainability in Challenging Fiscal Times" sponsored by Senator Diane Feinstein, at Homewood Mountain Ski Resort in California.

The twelve-minute movie by USGS Video Producer Stephen M. Wessells features USGS science activities beginning in 1895 and continues through research being conducted today by hydrologists, geologists, geographers, computer modelers, and biologists.

The video showcases a broad range of USGS science, including water quality monitoring, streamgaging, Lake Tahoe bathymetry, aerial LIDAR, historic use of aerial photography, and the Tahoe Land Use Simulation Model. This wide range of consistent, reliable, long-term data and maps are crucial for evaluating and maintaining the ecosystem health of the lake and basin.

This nontechnical, educational film is available on the USGS YouTube site as well as on various video sharing websites.