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Wildland fires in the western United States are wreaking havoc on the people, plants and wildlife in their way. As of July 13, more than 50 thousand fires had burned 2,832,759 acres in 2007. This area burned is 20 percent more than the 10-year average (1997-2007) for the same date. For details, go to the National Interagency Fire Center Web site. This July edition of Science Picks provides a compilation of fire science and other hot topics. USGS scientists have investigated the effects of wildland fire on plants, wildlife, water, soils and people to answer fire science questions asked by land managers. USGS offers critical real-time fire information to managers with tools such as GeoMAC (see below).

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July Highlights

• Natural Perchlorate in Southwest Soils May Exceed Total Amount Manufactured to Date
• Pesticides - A Tough Break(down) for Amphibians
• Biologists Hot on Tortoise Track
• The Hot Spots in Mojave Desert Wildfires of the Past 25 Years
• Fire-fueling Invader Gets Up Early
• Given a (Fuel) Break, Nonnative Plants Can Invade Wildlands
• Marsh Health - Counting Parasites a Positive
• Beetles, Bark, and other Battles that Influence Wildland Fire Risk
• Fire Tools and Resources
  • GeoMAC
  • California Fire Planning and Mapping Tools
  • Sierra Wildland Fire Reporting System
  • National Fire Plan
  • Rapid Data Delivery System
• How Long Does it Take Water to Flow through Aurora?
• Are Night Lights Bad for Wildlife?

The environmental and health communities are concerned about perchlorate, a naturally occurring and manmade chemical that has contaminated water supplies and is assumed to cause health problems. Just below the root zone in deserts and semi-arid regions throughout the southwestern United States are salt-rich layers containing substantial quantities of natural perchlorate. The amount, up to hundreds of grams per hectare, is surprising because the amount of the naturally occurring chemical may exceed the total amount manufactured to date. Want to know how the presence of natural perchlorate could complicate investigations at contamination sites? See the Widespread Accumulations of Natural Perchlorate in Southwestern Soils page or contact David Stonestrom at (650) 329-4528 or dastones@usgs.gov.

The breakdown products of the three most commonly used pesticides in California's agricultural Central Valley are found to be much more toxic to amphibians than their parent compounds, according to laboratory experiments conducted by the USGS and Southern Illinois University scientists. Tadpoles of foothill yellow-legged frogs were raised from eggs collected from a stream in the California Coast Range, upwind of agricultural activities in the Central Valley and away from areas where significant quantities of pesticides are used. Test results indicated that chloroxon killed all tadpoles and was at least 100 times more toxic than the lowest concentration of the parent compound chlorpyrifos, which resulted in no mortality. Maloxon was nearly 100 times more toxic than malathion, and diazoxon was about 10 times more toxic than diazinon. To learn more about this study, see the USGS news release "Research Finds That Breakdown Products of Widely Used Pesticides are Acutely Lethal to Amphibians " or contact Gary Fellers at (415) 464-5185 or gary_fellers@usgs.gov. Photos are also available.

Two years ago, tens of thousands of acres of desert tortoise critical habitat were burned in fires fueled primarily by invasive grasses. Charred remains of desert tortoises were found at several sites, but live tortoises also persisted in burned areas and the nearby perimeter. To determine if and how tortoises are using the habitats on and near large burned sites in the Mojave Desert, scientists are tracking the movements of desert tortoises in summer. To learn more, contact Ken Nussear at (702) 564-4515 or knussear@usgs.gov.

Historically, fire has been infrequent in the Mojave Desert; its increased occurrence, caused by the invasion of non-native annual grasses, is a major concern. Recent studies of fire data retrieved between 1980 and 2004 show the most dramatic changes have taken place in middle elevation shrublands — home to Joshua trees and desert tortoises. Research indicates that a more aggressive invasive plant/fire cycle exists in middle and possibly lower elevation shrublands, but not at higher elevations. For more information, see the news release "Spatial and Temporal Patterns of Wildfires in the Mojave Desert " or contact Matt Brooks at (702) 564-4615 or matt_brooks@usgs.gov.

By fueling wildfires that injure and kill native plants, Red brome (a non-native annual grass) is having a dramatic impact on Mojave Desert plant communities. According to scientists from the USGS, the Nevada Agricultural Experiment Station, and the University of Nevada Red brome affects perennial species in undisturbed plant communities even before wildfire becomes a problem. Research indicates growth of Mojave Desert perennials declined because nearby red brome plants that established in winter had 2 to 3 months of growth before perennials were active. In comparison, red brome plants that established later in spring were smaller and did not effectively reduce growth of the perennials. For more information, see the news release "Competitive Interactions Between a Non-native Annual Grass and Mojave Desert Perennials " or contact Lesley DeFalco at (702) 564-4507 or lesley_defalco@usgs.gov.

Federal, state, local and private land managers in the United States have made reducing hazardous fuels that feed wildland fires a priority, but fuel modification programs can unintentionally introduce and spread nonnative invasive plant species, according to a newly published report. After completing a study of fuel breaks — which included construction methods, maintenance and fire histories — on California forests and shrublands (sage scrub, chaparral, oak woodland, and coniferous forests), USGS and Forest service scientists say the cover and diversity of nonnative species were significantly higher on fuel breaks than in surrounding wildland areas. To learn more, check out the newly released report titled "The Role of Fuel Breaks in the Invasion of Nonnative Plants " or contact Jon Keeley at (559) 565-3170 or jon_keeley@usgs.gov.

When a beetle bores into bark, a healthy tree responds by producing pitch that drowns or evicts the beetle. During drought, however, trees may not produce enough sap pressure to control the hundreds of beetles that may attack. The insects carve pathways under the bark, eventually killing the afflicted trees. Those trees become fuel for wildfire. In 2006, the USGS and a multi-agency group of collaborators launched a multidisciplinary fire science project, “Assessment of Wildfire-Related Hazards on Human and Ecological Communities: A demonstration project in the Front Range of Colorado.” The team of scientists is conducting a comprehensive, systematic analysis of wildland fire risks and potential impacts, including post-fire effects on human safety, property, critical infrastructure and natural resources. Grand County, Colo., was chosen as the site of this project because of its extensive tree mortality from bark beetle outbreak, ongoing drought, a growing population in the wildland-urban interface, and the presence of significant water resources that supply municipal and agricultural users. For more information, contact Deborah Martin at (303) 541-3024 and damartin@usgs.gov or Randy Updike at (303) 236-5440 and updike@usgs.gov.

Ever watched coastal marsh birds swoop down on its unsuspecting prey and wondered if the salt marsh is healthy? How would you tell? To answer this question, scientists at the USGS, Princeton University, and the University of California, Santa Barbara, are cracking open common marsh snails and counting parasitic worms. Their claim: the more parasites, the healthier the marsh. Parasites seem small and invisible, hidden inside their hosts. However, parasites strongly affect the structure of food webs, and parasite links are necessary for measuring ecosystem stability. To learn more, see the Sound Waves news article on "Biologists Count Parasites to Assess Health of Marshand" and "Parasites, the Thread of Food Webs?" or contact Kevin Lafferty at (805) 893-8778 and klafferty@usgs.gov.

GeoMAC, an internet-based mapping application designed for fire managers and the public, shows dynamic online maps of current fire locations and fire perimeters in the continental United States and Alaska. In 2006, more than 2000 perimeters were loaded into the database.

The Fire Planning and Mapping Tools Web site is a user-friendly site where users can quickly create a map of an area, print, and download data to their PC for use with GIS software.

The Sierra Wildland Fire Reporting System application is a prototype comprehensive reporting system for all federal fires in the southern and central Sierra Nevada range. This tool can enhance fire managers' ability to collaborate and better understand fire and smoke impacts across multi-agency landscapes. This application provides reporting forms and tools for digitizing point and perimeter locations for small fires.

The National Fire Plan was developed in August 2000, following a landmark wildland fire season, to actively respond to severe wildland fires and their impacts to communities while ensuring sufficient firefighting capacity for the future. The plan addresses five key points: Firefighting, Rehabilitation, Hazardous Fuels Reduction, Community Assistance, and Accountability. The National Fire Plan web-based application shows the completed fuel treatment sites and communities at risk with base layer information, as well as the proposed fuel treatments for contractors’ information.

The USGS has started an internet-based data ordering service for use in wildfire applications for GIS specialists and fire managers. The application features interactive maps integrated with current wildfire information that can process and re-project mosaic and tone balance Digital Raster Graphics, Digital Orthophoto Quads, and Digital Elevation Models and automatically disseminate the data for users to download or to initiate a delivery of data on CD-ROM using traditional mail delivery methods. (Note: the RDDS site is password protected and access is limited to wildland fire personnel)

• Rapid Data Delivery System

USGS science will be prominently featured in a four-part, high-definition television series called "Faces of the Earth" on the Science Channel. The series includes the following episodes and premier showtimes: "Building the Planet," July 23 at 9 p.m.; "Shaping the Planet," July 26 at 9 p.m.; "Assembling America," Aug. 2 at 10 p.m., and "The Human World," Aug. 9 at 9 p.m. "Faces of the Earth" is produced by the American Geological Institute and Evergreen Films and is intended to let the viewer follow scientists at work, and see the world like never before. To learn more about “Faces of Earth,” find additional show times, and to watch trailers from the series, go to http://www.facesofearth.tv. For more information, contact Robert Ridky at (703) 648-4713 or rridky@usgs.gov.

The USGS Colorado Water Science Center is conducting rhodamine, "red-dye" tests along Toll Gate Creek in Aurora, Colo., July 9 through August 7. The study will provide estimates of the time it takes for water in the creek to flow through Aurora. These estimates can be used to understand the movement of contaminants that can be introduced to the stream either by design or as the result of an accidental spill. The study is part of ongoing work by the USGS and the City of Aurora. For more information, contact Heidi Koontz at (303) 202-4763 or hkoontz@usgs.gov.

When camping out in the wild, away from the city, even under a clear, starlit sky, most of us like to have a flashlight to light our way. Lights help humans to navigate outside at night, but what do wildlife make of our artificial illumination? Artificial night lighting may affect the behavior of wildlife in complex ways and may even contribute to declines in some reptile species, according to USGS and Texas Tech University scientists. To learn more, see Sound Waves article "Are Artificial Night Lights Among Threats to Declining Reptiles? " or contact Robert Fisher at (619) 225-6422 or rfisher@usgs.gov.