Wind Turbine or Tree? Certain Bats Might Not Know
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 29, 2014.Summary: Certain bats may be approaching wind turbines after mistaking them for trees, according to a study published in the Proceedings of the National Academy of Sciences
FORT COLLINS, Colorado – Certain bats may be approaching wind turbines after mistaking them for trees, according to a study published in the Proceedings of the National Academy of Sciences.
The study, led by U.S. Geological Survey scientist Paul Cryan, was the first to use video surveillance cameras to watch bats for several months flying at night near experimentally manipulated wind turbines and led to the discovery that tree-roosting bats, or “tree bats,” may approach and interact with wind turbines in consistent and predictable ways.
Bats are long-lived, slow-breeding mammals that serve as the main predators of night flying insects, such as moths and beetles. Insect-eating bats are estimated to save farmers billions of dollars each year in the United States by providing natural pest control. Historically, fatal collisions of bats and tall, human-made structures were rarely observed, but something changed with the construction of large, industrial wind turbines. It is now estimated that tens to hundreds of thousands of bats die each year after interacting with the moving blades of wind turbines. Most tree bats are found dead beneath turbines in late summer and autumn, yet reasons for this seasonal susceptibility remain a mystery – unknown behaviors of bats may play a role.
"If we can understand why bats approach wind turbines, we may be able to turn them away," said Paul Cryan, a USGS research scientist and the study’s lead author. "Advances in technology helped us overcome the difficulties of watching small bats flying in the dark around the 40-story heights of wind turbines. The new behaviors we saw are useful clues in the quest to know how bats perceive wind turbines and why they approach them."
The researchers used ‘thermal’ cameras that image heat instead of light, and they recorded surveillance imagery of bats for several months at three wind turbines in Indiana. The team also monitored the nighttime airspace around turbines with near-infrared security cameras, radar and machines that record the ultrasonic calls of bats, as well as developed computer code for automatically finding bats in the hundreds of hours of recorded video imagery. Over the period of the study, bats were seen on video near turbines more than 900 times.
Bats typically approached turbines one or more times rather than just flying past, and bats often flew very close to the turbine monopoles, nacelles (machinery boxes at top of monopoles) and sometimes approached stationary or slow-moving blades. At the same time, radar indicated that hundreds of night-migrating birds were flying above and around the turbines nightly, but not closely approaching like bats.
The most surprising discovery was that bats more often approached wind turbines high above the ground and from the downwind side when the wind was blowing. This strong pattern strengthened as wind speed increased and when turbine blades were experimentally prevented from turning at full speed, but decreased in high winds when turbine blades spun normally. Bats also appeared at turbines more often during brightly moonlit nights. The authors concluded from these patterns that bats might follow airflow paths around tree-like structures and use visual cues at night, but may not be able to tell a tree from a wind turbine with slow or stopped blades.
"The way bats approach turbines suggests they follow air currents and use their dim-adapted vision to find and closely investigate tall things shaped like trees," said Marcos Gorresen, an author of the study and scientist with the University of Hawaii at Hilo. "We see these behaviors less often on darker nights and when fast-moving turbine blades are creating chaotic downwind turbulence. This may be because bats are less likely to mistake turbines for trees and approach them in those conditions."
Previous studies indicated that bat fatalities at wind turbines might occur more often on nights with low average wind speeds. The authors speculate that bats may be more likely to approach turbines in such conditions when turbines have airflow patterns resembling trees, but then might be put at risk if wind speed rapidly increases and pushes turbine blades to speeds faster than bats can perceive or outmaneuver.
Although these new findings revealed bats closely investigating most parts of the turbines, the study could not determine their reasons for doing so. The authors wonder if bats might expect to find roosts, clouds of insect prey or other bats at turbines as they might at trees, regardless of whether such resources actually occur at wind turbines. Little is known about the behaviors of bats or insects around tall trees during late summer and autumn, but the authors write that studying treetop behaviors in natural environments might help explain why bats are particularly susceptible to wind turbines.
The new findings also have practical implications toward the goal of reducing or avoiding bat fatalities at wind turbines. A current method of reducing bat fatalities at wind turbines is to increase the wind speed threshold at which turbine blades begin operating and spinning fast. “It might be possible to efficiently further reduce fatalities with this method by accounting for sporadic gusts of wind during low-wind periods when bats might be hanging around turbines,” said Cris Hein, an author of the study and scientist with Bat Conservation International. The findings also suggest that pointing monitoring or deterrent devices into the downwind airspace of a turbine might have better chances of detecting or keeping bats away than if they are pointed elsewhere.
The authors conclude that increasing our understanding of the ways that bats perceive and approach wind turbines helps in the search for solutions to reduce the effects of this important energy source on bat populations. More information about this study and additional bat research is available online at the USGSFort Collins Science Center, Bat Conservation International and Bats and Wind Energy Cooperative.
Past, Present and Future Climates Go Hand in Hand with Tribes
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 25, 2014.Summary: Collaboration between federal Climate Science Centers, partner agencies and tribes is vital for minimizing and adapting to potential harmful effects of climate change on human society and surrounding ecosystems, according to a newly-released U.S. Geological Survey circular
Collaboration between federal Climate Science Centers, partner agencies and tribes is vital for minimizing and adapting to potential harmful effects of climate change on human society and surrounding ecosystems, according to a newly-released U.S. Geological Survey circular.
“All eight of our Climate Science Centers are working closely with tribal nations to develop the practical science they need," said Anne Castle, DOI Assistant Secretary for Water and Science, "and we are looking forward to the addition of five new BIA tribal liaison positions within the CSC network to help bring climate science results directly to tribal governments.”
The South Central CSC provides climate science training and science tools that can help tribes assess their natural and cultural resource vulnerabilities and develop adaptation strategies. The circular also provides resources related to funding opportunities, climate science resources and partnership contacts.
Eight Climate Science Centers were established by the U.S. Department of the Interior between 2010 and 2012 to increase understanding of climate change and coordinate an effective response to climate change effects on the natural and cultural resources that DOI manages.
“It is our intent to share climate change mitigation and adaptation information with tribes and to receive feedback from tribal members regarding how ecosystems and cultural resources can be maintained as climate changes,” said Kim Winton, USGS scientist and director of the SC CSC.
The SC CSC gives natural resource managers the science, tools and information they need to mitigate and adapt to the effects of climate variability and change on their areas of responsibility. The mission of the Climate Science Center is to produce “actionable science,” or science that can be utilized to make resource management decisions such as responding to drought, fire, invasive species and other environmental issues.
This new USGS circular describes issues of interest to the 68 Native American tribes in the south-central United States, the programs and initiatives of the SC CSC and means of sharing climate science knowledge with tribes in the south central United States.
“Through two-way communication of interests, knowledge and concern about climate change and related issues, the needs of tribes in the south central United States will be better served, and interpretation of the effects of climate change in this region will be strengthened,” said Winton.
Captive Whooping Cranes Released Into the Wild
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 23, 2014.Summary: Four whooping crane chicks raised in captivity began their integration into the wild Saturday as part of the continuing effort to increase the wild population of this endangered species
Efforts continue to increase population of endangered bird
NECEDAH, Wis. – Four whooping crane chicks raised in captivity began their integration into the wild Saturday as part of the continuing effort to increase the wild population of this endangered species.
The cranes, hatched and raised by their parents at the U.S. Geological Survey’s Patuxent Wildlife Research Center in Laurel, Maryland, were released on the U.S. Fish and Wildlife Service’s Necedah National Wildlife Refuge in Wisconsin.
The chicks, about six-months old, are part of an experimental rearing and release method referred to as “parent-rearing.” The parent-reared whooping crane chicks were hatched and raised by captive adult whooping cranes. This method relies entirely on the expertise of captive parents, who care for, exercise, and feed the chicks.
These chicks will join a flock of about 95 cranes that inhabit wetlands on the refuge and elsewhere in central Wisconsin during the spring and summer. The flock is composed of cranes reintroduced into the wild in order to establish a migratory flock of whooping cranes in the eastern United States. The Eastern Migratory Flock flies south to wetlands in the Southeast United States for the winter. The USGS Patuxent Wildlife Research Center also raises chicks for release into a newly established non-migratory flock in the wetlands of Southwest Louisiana.
“Over the past 13 years, USGS biologists – dressed in costumes to avoid having the birds “imprint” on people -- have raised between five and 20 whooping crane chicks annually that have been released into the Eastern Migratory Flock,” said John French, leader of the USGS whooping crane project at Patuxent. “This new method of allowing captive adult cranes rear the chicks prior to release into the wild is intended to evaluate the effects of rearing by humans in costume, which is obviously an odd condition. Parent rearing may result in the chicks learning behavior important to their survival and reproduction.”
While the parent-rearing method has been used previously with sandhill cranes in Mississippi and whooping cranes in Florida, this is only the second year it has been attempted with a migratory population.
“Our refuge has a long history of helping with the successful reintroduction of endangered or threatened bird species to the area,” said Doug Staller, Necedah National Wildlife Refuge manager. “Necedah is the summer home for the bulk of the Eastern Migratory Flock of whooping cranes, some of which are breeding, and provides a unique and important opportunity to learn more about these endangered birds. It was only natural for us to be involved in the parent rearing effort.”
The parent-reared chicks arrived at Necedah NWR Saturday, where they were housed in separate predator resistant enclosures to provide them a safe place for chicks to roost while they acclimated to their new surroundings near other free-ranging whooping cranes.
The pens are located in the vicinity of pairs of adult whooping cranes without chicks of their own. Such pairs have a tendency to adopt other chicks, and when adopted, will lead them south during migration, which begins at the end of October.
In addition to the four parent-reared chicks released at Necedah NWR, seven costumed-reared whooping crane chicks will join the eastern migratory flock this year as well. The chicks were raised in captivity by costumed handlers and have been imprinted on an ultralight aircraft. They will earn the migration route by following the ultralight from White River Marsh in Wisconsin to the Gulf Coast of Florida. More information on the migration will be available when it begins in October.
All of the releases of whooping cranes in Wisconsin add to the Eastern Migratory Flock, a reintroduction project undertaken by a broad coalition of Federal, state, and NGO partners belonging to the Whooping Crane Eastern Partnership.
At one point in the past, researchers believe the Whooping crane population dropped to fewer than two-dozen birds. Today the population is estimated to be approximately 425 in the wild, with another 125 in captivity.
We Will Rock You - Geologic Map Day
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 23, 2014.Summary: Celebrate the third annual Geologic Map Day! On October 17, as a part of the Earth Science Week 2014 activities, join leading geoscience organizations in promoting awareness of the importance of geologic mapping to society
The U.S. Geological Survey is partnering with the American Geosciences Institute, the Association of American State Geologists and others to promote the importance of geologic mapping to society.
Celebrate the third annual Geologic Map Day! On October 17, as a part of the Earth Science Week 2014 activities, join leading geoscience organizations in promoting awareness of the importance of geologic mapping to society.
Geologic maps are vital to education, science, business, and public policy concerns. Geologic Map Day will focus the attention of students, teachers, and the general public on the study, uses, and significance of these tools, by engaging audiences through educational activities, print materials, online resources, and public outreach opportunities.
Be sure to check out the Geologic Map Day poster included in this year’s Earth Science Week Toolkit. The poster and other materials in the kit show how geologic maps can be used to understand natural hazards as well as providing step-by-step instructions for a related classroom activity focusing on the Grand Canyon. Additional resources for learning about geologic maps can be found on the Geologic Map Day web page.
Geologic Map Day partners include the American Geosciences Institute (AGI), the Association of American State Geologists, the U.S. Geological Survey, the National Park Service, the Geological Society of America, and Esri.
For more information, go to: http://www.earthsciweek.org/geologicmap/
|Geologic map of the conterminous United States at 1:2,500,000 scale. (High resolution image)|
Streamgages Measure Drought, Earthquake Impacts on Water
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 16, 2014.Summary: While the national streamflow database is documenting evidence of California’s historic drought, the database is also confirming another recently seen hydrologic phenomenon: earthquake-induced increases in streamflow
|Hydrograph showing stream flow in cubic feet per second on USGS streamgage on Sonoma Creek near Agua Caliente, from about August 23 - September 13, 2014. The sharp rise starting on August 24 reflects an increased streamflow due to the South Napa Earthquake. (High resolution image)|
|Hydrograph showing stream flow in cubic feet per second on USGS streamgage on Sonoma Creek near Agua Caliente, from April 1 - mid-September, 2014. The steady decline in streamflow reflects current drought conditions in California. The sharp decrease and increase aroundAugust 1 is a regional trend, reflecting an upstream irrigation diversion.The sharp rise starting on August 24 reflects an increased streamflow due to the South Napa Earthquake. (High resolution image)|
|Hydrograph showing an increase of gage-height in feet (.01 increments) at the Sonoma Creek at Agua Caliente gage, in the early morning of August 24, 2014. The sharp rise in water level between 4:15 - 4:30 a.m. reflects an increased streamflow due to the South Napa Earthquake an hour earlier. (High resolution image)|
SACRAMENTO, Calif. — While the national streamflow database is documenting evidence of California’s historic drought, the database is also confirming another recently seen hydrologic phenomenon: earthquake-induced increases in streamflow.
Rivers and streams across California are flowing at record lows. Streamflow data from 182 U.S. Geological Survey streamgages in California with at least 30 years of record, currently show that 62 percent of streamgages are recording flows less 25 percent of normal, and 44 percent are recording flows less than 10 percent of normal. At several streamgage sites, scientists have had to extend measurement scales and rating formulas that help calculate accurate streamflow, because of record low water flows.
|Increased flow over rock riffle in Sonoma Creek seen after South Napa Earthquake of August 24, 2014. (High resolution image)|
Meanwhile, in the aftermath of the August 24 magnitude 6.0 South Napa Earthquake in California, water has begun to flow again in some previously-dry surrounding creeks, rivers and streams prompting many nearby residents to scratch their heads.
Hydrogeologic responses to earthquakes have been known by scientists for decades. In the case of the South Napa Earthquake, the discharge of springs and groundwater to some streams has increased. Based on experience in previous earthquakes, stream and spring flows are expected to decline again over the next several months, assuming that the Napa region does not get significant rainfall over that time period.
Post-earthquake changes in streamflow were recorded at a USGS streamgage on Sonoma Creek, near the city of Sonoma where measured increases in streamflow began after 4:15 a.m. on August 24, about an hour after the earthquake occurred. Streamflow has increased intermittently since the earthquake from 0.1 cubic feet per second to nearly 3 cfs on September 12. The median historical streamflow for this time period is about 0.5 cfs. Scientists theorize that this increase in streamflow is due to groundwater flow entering the river, and the intermittent nature of the streamflow is due to the non-uniform release of groundwater across the basin.
Related Links and Resources
- U.S. Drought Monitor.
- The California Drought
- Hydrologic responses to earthquakes, USGS Fact Sheet 096-03, “Earthquakes—Rattling the Earth’s Plumbing System.”
- Current information for streamflow along the Sonoma Creek at Agua Caliente.
- Information about the August 24 South Napa Earthquake.
Media Advisory: USGS to Host Congressional Briefing: #StrongAfterSandy--The Science Supporting the Department of the Interior's Response
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 15, 2014.Summary: Department of the Interior scientists are generating and sharing critical information to aid the recovery of the areas impacted by Hurricane Sandy, helping to protect our valuable coastal resources and to make communities more resilient against future extreme storms
Hannah Hamilton ( Phone: 703-648-4356 (work) 703-314-1601 (cell) );
Department of the Interior scientists are generating and sharing critical information to aid the recovery of the areas impacted by Hurricane Sandy, helping to protect our valuable coastal resources and to make communities more resilient against future extreme storms. Moving forward DOI is positioned to help answer questions such as: What locations along the coast are forecasted to be the most vulnerable to future hurricanes? What were the storm impacts to ecosystems, habitats, fish and wildlife? What is being learned about the importance of undeveloped land? Come learn how the U.S. Geological Survey and its partners are working to assemble and apply better data to keep citizens safe.
|Claude Gascon, Executive Vice President and Chief Science Officer, National Fish and Wildlife Foundation
|Rayburn House Office Building, Room 2325, Washington, D.C.
|Friday, September 19, 2014 – 11:00 a.m.
|Refreshments provided courtesy of the National Fish and Wildlife Foundation|
To learn how USGS is combining interdisciplinary science with state-of-the-art technologies to achieve a comprehensive understanding of coastal change caused by Hurricane Sandy, read our new fact sheet: Using Science to Strengthen our Nation’s Resilience to Tomorrow’s Challenges—Understanding and Preparing for Coastal Impacts.
New Oregon Maps Feature National Scenic Trails
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 15, 2014.Summary: Newly released US Topo maps for Oregon now feature segments of the Pacific Crest National Scenic Trail
Newly released US Topo maps for Oregon now feature segments of the Pacific Crest National Scenic Trail. Several of the 1,835 new US Topo quadrangles for the state now display parts of the Trail along with other improved data layers.
“Having the Pacific Crest NST finally show up on Oregon US Topo maps is significant for all of the recreational users of the wild spaces the trail traverses,” said Tom Carlson, Geospatial Liaison for the Pacific Northwest. “Hiking the trail provides commanding views of the volcanic peaks of the Cascade Range as well as the verdant forests of the western side of the mountains and down into the farmlands of the Willamette Valley. You also see parts of the open Ponderosa Pine forest and high desert on the eastern slopes of the mountains.”
The Pacific Crest National Scenic Trail is a treasured pathway through some of the most scenic terrain in the nation. Beginning in southern California at the Mexican border, the PCT travels a total distance of 2,650 miles through California, Oregon, and Washington until reaching the Canadian border. The PCT is one of the original National Scenic Trails established by Congress in the 1968 National Trails System Act and fifty-four percent of the trail lies within designated wilderness.
The USGS partnered with the U.S. Forest Service to incorporate the trail onto the Oregon US Topo maps. This NST joins the Ice Age National Scenic Trail, the Pacific Northwest National Scenic Trail and the North Country National Scenic Trail as being featured on the new US Topo quads. The USGS hopes to eventually include all National Scenic Trails in The National Map products.
Another important addition to the new Oregon US Topo maps in the inclusion of Public Land Survey System. PLSS is a way of subdividing and describing land in the US. 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.
To compare change over time, scans of legacy USGS topo maps, some dating back to the late 1800s, can be downloaded from the USGS Historical Topographic Map Collection
To download US Topo maps: http://nationalmap.gov/ustopo/
|The National Trails System was established by Act of Congress in 1968. The Act grants the Secretary of Interior and the Secretary of Agriculture authority over the National Trails System. The Act defines four types of trails. Two of these types, the National Historic Trails and National Scenic Trails, can only be designated by Act of Congress. National scenic trails are extended trails located as to provide for maximum outdoor recreation potential and for the conservation and enjoyment of nationally significant scenic, historic, natural, and cultural qualities of the area through which such trails may pass.
There are 11 National Scenic Trails:
|New 2014 US Topo quadrangle of the Three Fingered Jack, Oregon, area. Scale 1:24,000, with the orthoimagery layer turned on. (high resolution image)||Scanned copy of the 1929 USGS Three Sister’s, Oregon, quadrangle. Scale 1:25,000 – from the USGS Historical Topographic Map Collection. (high resolution image)|
20-Year Study Shows Levels of Pesticides Still a Concern for Aquatic Life in U.S. Rivers and Streams
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 11, 2014.Summary: Levels of pesticides continue to be a concern for aquatic life in many of the Nation’s rivers and streams in agricultural and urban areas, according to a new USGS study spanning two decades (1992-2011)
Levels of pesticides continue to be a concern for aquatic life in many of the Nation’s rivers and streams in agricultural and urban areas, according to a new USGS study spanning two decades (1992-2011). Pesticide levels seldom exceeded human health benchmarks.
Over half a billion pounds of pesticides are used annually in the U.S. to increase crop production and reduce insect-borne disease, but some of these pesticides are occurring at concentrations that pose a concern for aquatic life.
|High resolution image|
The proportion of streams with one or more pesticides that exceeded an aquatic-life benchmark was similar between the two decades for streams and rivers draining agricultural and mixed-land use areas, but much greater during the 2002-2011 for streams draining urban areas.
Fipronil, an insecticide that disrupts the central nervous system of insects, was the pesticide most frequently found at levels of potential concern for aquatic organisms in urban streams during 2002-2011.
“The information gained through this important research is critical to the evaluation of the risks associated with existing levels of pesticides,” said William Werkheiser, USGS Associate Director for Water.
Since 1992, there have been widespread trends in concentrations of individual pesticides, some down and some up, mainly driven by shifts in pesticide use due to regulatory changes, market forces, and introduction of new pesticides. “Levels of diazinon, one of the most frequently detected insecticides during the 1990s, decreased from about 1997 through 2011 due to reduced agricultural use and the U.S. Environmental Protection Agency’s regulatory phase-out of urban uses,” said, Wesley Stone, USGS hydrologist.
The potential for adverse effects on aquatic life is likely underestimated in these results because resource constraints limited the scope of monitoring to less than half of the more than 400 pesticides currently used in agriculture each year and monitoring focused only on pesticides dissolved in water.
The USGS National Water-Quality Assessment Program is continually working to fill these data gaps by adding new pesticides that come into use, such as the neonicotinoid and pyrethroid insecticides, improving characterization of short-term acute exposures, and enhancing evaluations of sediment and other environmental media.
The study “Pesticides in U.S. Streams and Rivers: Occurrence and trends during 1992-2011” is a feature article in the Environmental Science and Technology journal. The article and additional information including data, reports, and maps on pesticide status, trends, and use are available online.
Ocean Warming Affecting Florida Reefs
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 09, 2014.Summary: Late-summer water temperatures near the Florida Keys were warmer by nearly 2 degrees Fahrenheit in the last several decades compared to a century earlier, according to a new study by the U.S. Geological Survey
Increased Temperatures Spell Trouble for Corals
ST. PETERSBURG, Fla.— Late-summer water temperatures near the Florida Keys were warmer by nearly 2 degrees Fahrenheit in the last several decades compared to a century earlier, according to a new study by the U.S. Geological Survey.
Researchers indicate that the warmer water temperatures are stressing corals and increasing the number of bleaching events, where corals become white resulting from a loss of their symbiotic algae. The corals can starve to death if the condition is prolonged.
“Our analysis shows that corals in the study areas are now regularly experiencing temperatures above 84 F during July, August and September; average temperatures that were seldom reached 120 years ago,” said Ilsa Kuffner, a USGS research marine biologist and the study’s lead author. “When corals are exposed to water temperatures above 84 F they grow more slowly and, during extended exposure periods, can stop growing altogether or die.”
The new analysis compares water temperatures during two time periods a century apart at two of Florida’s historic offshore lighthouses – Fowey Rocks Lighthouse, off Miami, and Carysfort Reef Lighthouse, off Key Largo, Florida. The first period included data from 1879 to 1912, while the second period spanned from 1991 to 2012. Temperatures at a third area, a reef off Islamorada, Florida, were also monitored from 1975 to 2007.
“What’s interesting is that the temperature increase observed during this recent 32-year period was as large as that measured at the lighthouses spanning 120 years,” said Kuffner. “This makes it likely the warming observed at the lighthouses has actually occurred since the 1970s.”
The study indicates that August is consistently the month when Florida’s ocean temperatures peak. In the analysis of recent decades, average temperatures for August have been at or very close to 86 F. At Fowey Lighthouse from 1879 to 1912, the average August temperature was just 84.2 F. Temperatures this August at the same location, though not included in the study, averaged 87 F.
Coral bleaching is currently underway in the Florida Keys, highlighting the real-time impact that warmer ocean temperatures are having on reefs. Corals can recover from bleaching if the waters cool down within a few weeks, but mortality usually ensues if corals remain bleached longer than a month or two.
The study, “A century of ocean warming on Florida Keys coral reefs: Historic in-situ observations,” was recently published in the journal Estuaries and Coasts and is available via open access.
Research Shows Historic Decline in Pacific Walrus Population
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 08, 2014.Summary: The Pacific walrus population roughly halved between 1981 and 1999, the last year for which demographic data are available. A recent study by scientists at the U.S. Geological Survey quantifies this historic population decline
ANCHORAGE, Alaska — The Pacific walrus population roughly halved between 1981 and 1999, the last year for which demographic data are available. A recent study by scientists at the U.S. Geological Survey quantifies this historic population decline. The 18 year decline identified by the study was not steady across that period. The decline was most severe in the mid-1980s, and then moderated in the 1990s.
If the moderating trend has continued up to the present time then the population might be stabilized. That, however, cannot be determined until more recent data are collected and analyzed. USGS is working to obtain the data needed to close the gap from collection of the last demographic data to the present day. This information will be vital because the U.S. Fish & Wildlife Service is expected to determine whether the Pacific walrus should be listed as threatened under the Endangered Species Act in 2017. Population dynamics, such as those investigated in this USGS study, will be a critical factor in the decision.
“We integrated data from many sources,” said lead author of the study research statistician Rebecca Taylor, with the USGS Alaska Science Center in Anchorage. “These included annual harvest records, 6 age structure surveys and 5 population size surveys conducted at various times over the 32 year study. The age structure data—collected between 1981 and 1999—were particularly informative, and enabled us to quantify the population decline and the birth and death rates that caused it.”
Scientists think past walrus population dynamics were affected mainly by harvest. Previous work suggests the population probably increased rapidly in the 1960s due to reduced hunting and reached or exceeded the size that could be supported by food resources in the late 1970s to early 1980s. The decline quantified by the USGS analysis was probably initiated by this overabundance of walruses and exacerbated by a return to the relatively high harvests of the 1980s.
“The decline probably was prompted by these historical reasons, but we can’t rule out other possible contributing factors,” said Taylor. “The environment isn’t static, and food may have become less available to walruses over time, possibly because of sea ice loss.” Sea ice is important to walruses because they rest on it between dives to the ocean floor to eat clams and other invertebrates.
Taylor’s analytical approach allows the incorporation of new data to understand more recent population dynamics. In 2013 and 2014, the USGS, USFWS and the Alaska Department of Fish & Game jointly surveyed walruses in Bering Strait and the Chukchi Sea to estimate current age structures and test a new method of estimating population size using a genetic mark-and-recapture approach. Another survey is planned for 2015.
In 2011, due to the combined threats of harvest and sea ice loss, the USFWS determined that listing of the population as threatened under the Endangered Species Act was warranted but was precluded by higher priorities. The agency is under a court order to make a listing decision in 2017.
For further information:
Multimedia Gallery links:
Media Advisory: Earthquake 101: Resources for Reporting on Earthquakes
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 04, 2014.Summary: The U.S. Geological Survey will host an educational event for the news media focused on earthquakes on Wednesday September 24, 2014
Media Advisory – Save the Date
MENLO PARK, Calif. — The U.S. Geological Survey will host an educational event for the news media focused on earthquakes on Wednesday September 24, 2014. The goal of the event is to provide the press an opportunity to work with USGS staff to build knowledge about and confidence in our information delivery systems and people to create more timely and accurate reporting of earthquakes.
At this event, USGS scientists and public affairs staff will lead sessions in which journalists can refresh knowledge about basic principles about earthquakes, how to improve scientific accuracy when reporting on earthquakes, and about USGS resources to make your job easier. Find out about USGS public domain maps, images, and graphics that can be quickly and freely downloaded and reused following an earthquake.
USGS geologists, geophysicists, and public affairs. See list below.
30-minute plenary session with presentations on reporting on earthquakes and relevant USGS resources, followed by concurrent small group discussions with USGS researchers on various aspects of earthquake science. Subjects will include:
Wednesday, September 24, 2014, 10:00 a.m. – 11:30 a.m. PDT
Please register online to participate in the workshop.
U.S. Geological Survey
The first 30 minutes of the event will be live video-streamed over the web, and archived online for later viewing.
Pollutant Risk Changes When Bugs Take Flight
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 04, 2014.Summary: Insects feed fish and wildlife higher on the food chain, but they can also transfer harmful contaminants to their predators according to new research conducted by the U.S. Geological Survey and published in Environmental Science and Technology
Heidi Koontz ( Phone: 303-202-4763 );
Insects feed fish and wildlife higher on the food chain, but they can also transfer harmful contaminants to their predators according to new research conducted by the U.S. Geological Survey and published in Environmental Science and Technology.
Because insects can transform from sedentary juveniles (larvae) to winged adults, contaminants accumulated as larvae can be carried to different locations potentially far from the pollution source.
The paper documents critical changes in insect contaminant concentrations and chemical tracers used to estimate position on the food chain during this transformation (a.k.a. metamorphosis).
“Most metals are lost during metamorphosis and are in higher concentrations in larvae than adults. Contaminants such as polychlorinated biphenyls (PCBs) are retained during metamorphosis and are in higher concentrations in adults than larvae,” said Johanna Kraus, a USGS scientist based in Ft. Collins, Colorado, and lead author of the ES&T paper. “As a result, the animals that eat insects, like bats, birds and fish may be exposed to higher contaminant concentrations depending on the contaminants and whether they are eating larval or adult insects.”
These results have large implications for managing and studying how far and how long it takes for contaminants to spread, and their effects on food webs across ecosystem boundaries. Metabolic regulation of contaminants generally predicts whether contaminants are excreted or concentrated in insect bodies during metamorphosis. Pollutants that magnify up the food chain tend to be retained and concentrated during metamorphosis.
This is the first paper to synthesize the general patterns and variation in contaminant transfer during a major developmental and habitat shift (e.g., water to land, ground to aerial) in animals with complex life cycles, as well as the first compilation of effects of metamorphosis on isotopic tracers used to estimate food web structure. The article was also selected as the American Chemical Society’s Editors' Choice paper (Sept. 2, 2014).
National Scenic Trails Added to Revised Michigan Maps
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 04, 2014.Summary: Newly released US Topo maps for Michigan now feature segments of the North Country National Scenic Trail. Several of the 1,290 new US Topo quadrangles for the state now display parts of the Trail along with other improved data layers.
Newly released US Topo maps for Michigan now feature segments of the North Country National Scenic Trail. Several of the 1,290 new US Topo quadrangles for the state now display parts of the Trail along with other improved data layers.
"USGS maps are excellent planning and navigation tools for hikers and other trail users” said Mark Weaver, Superintendent of the Trail. “The North Country Trail is a truly special recreational resource and we are quite thrilled to have the trail incorporated onto the maps.”
The North Country Trail is one of the 11 National Scenic Trails in the U.S. It is the longest national scenic trail, extending over seven states and 168 distinct land management units, from the vicinity of Crown Point State Park New York, to Lake Sakakawea State Park on the Missouri River in North Dakota, to the route of the Lewis and Clark National Historic Trail. Plans are underway to expand the trail to include the Arrowhead region of northern Minnesota, and extend the eastern terminus to the Appalachian Trail in Vermont, eventually bringing the trail to approximately 4,600 miles long.
"The North Country Trail tells the unique story of the people and the places in America's northern heartlands- the hardship of an unforgiving landscape, the joys of recreating in the Great North Woods and the challenges of making a living from the land without destroying it,” explained Bruce Matthews, Executive Director of the North Country Trail Association. “Being present on the USGS maps mean more people will become more deeply engaged with this story and with the North Country Trail.”
The USGS partnered with the National Park Service to incorporate the trail onto the Michigan US Topo maps. This NST joins the Ice Age National Scenic Trail, the Pacific Crest National Scenic Trail and the Pacific Northwest National Scenic Trail as being featured on the new Topo maps. The USGS hopes to eventually include all National Scenic Trails in The National Map products.
Another important addition to the new Michigan US Topo maps in the inclusion of Public Land Survey System. PLSS is a way of subdividing and describing land in the US. 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.
“The inclusion of a layer for the PLSS with township, range, and section information on the new US Topo maps for Michigan is a valuable addition,” said Charley Hickman, Geospatial Liaison to Ohio and Michigan. “Many of the stakeholder groups in Michigan who use USGS topographic maps and data have noted the importance of PLSS as a key reference layer. Thanks to the Bureau of Land Management and the State of Michigan for making this data available.”
To compare change over time, scans of legacy USGS topo maps, some dating back to the late 1800s, can be downloaded from the USGS Historical Topographic Map Collection
To download US Topo maps: US Topo Quadrangles — Maps for America
|The National Trails System was established by Act of Congress in 1968. The Act grants the Secretary of Interior and the Secretary of Agriculture authority over the National Trails System. The Act defines four types of trails. Two of these types, the National Historic Trails and National Scenic Trails, can only be designated by Act of Congress. National scenic trails are extended trails located as to provide for maximum outdoor recreation potential and for the conservation and enjoyment of nationally significant scenic, historic, natural, and cultural qualities of the area through which such trails may pass.(Larger image)||The North Country National Scenic Trail (NCNST) stretches 875 miles from New York to North Dakota. The trail enters Michigan near Morenci in the southeastern corner of the state. From there it heads northwest through both urban and rural settings toward certified trail segments in Manistee National Forest. It then takes a decided turn northward through the Jordan Valley and Wilderness State Park to cross the Straits of Mackinac. The Upper Peninsula segment of the trail system goes east to west starting in Hiawatha National Forest. It passes Tahquamenon Falls State Park, Pictured Rocks National Lakeshore, and parts of Ottawa National Forest before it exits Michigan at the town of Ironwood. Special attractions: A complete look at urban and rural Michigan, including Mackinac Bridge, Mackinac Island, Tahquamenon Falls, Pictured Rocks National Lakeshore, Porcupine Mountains. Click here for more info (Larger image)|
Media Advisory: Washington Governor Jay Inslee to Speak About Building Resilience at the Pacific Northwest Climate Science Conference
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 03, 2014.Summary: As part of the Planning Committee for the Fifth Annual Pacific Northwest Climate Science Conference, the Department of the Interior’s Northwest Climate Science Center is pleased to invite you to join more than 250 scientists and practitioners from the Northwest to learn the latest on Pacific Northwest climate science and adaptation, including presentations on landslides, wildfires, sea level rise, extreme weather events, natural resource and infrastructure vulnerability, human health and cultural impacts.
As part of the Planning Committee for the Fifth Annual Pacific Northwest Climate Science Conference, the Department of the Interior’s Northwest Climate Science Center is pleased to invite you to join more than 250 scientists and practitioners from the Northwest to learn the latest on Pacific Northwest climate science and adaptation, including presentations on landslides, wildfires, sea level rise, extreme weather events, natural resource and infrastructure vulnerability, human health and cultural impacts.
At 1:30 PM on Wednesday Washington Governor, Jay Inslee, will give a Keynote Address on increasing resilience in Washington State and the Northwest.
Who: Scientists, managers and administrators addressing climate change across a range of sectors. Plenary by Washington Governor, Jay Inslee.
When: The conference will be held Tuesday and Wednesday, September 9-10, 2014
Where: Kane Hall on the University of Washington Seattle campus. Click here for directions.
Members of news organizations and of science writers' associations are encouraged to attend the conference. To learn more and to RSVP contact Lisa Hayward Watts at email@example.com or 206-795-8843.
Avian Flu in Seals Could Infect People
By OC_Web@usgs.gov (Office of Communications and Publishing) from USGS Newsroom. Published on Sep 03, 2014.Summary: The avian flu virus that caused widespread harbor seal deaths in 2011 can easily spread to and infect other mammals and potentially humans
The avian flu virus that caused widespread harbor seal deaths in 2011 can easily spread to and infect other mammals and potentially humans.
A new study by the U.S. Geological Survey and St. Jude Children’s Research Hospital shows that the avian influenza H3N8 strain that infected New England harbor seals could be transmitted to other mammals through the air without physical contact. Transmission by respiratory droplets through coughing, for example, is the main way influenza viruses spread among people. The study also showed that current seasonal flu vaccines do not protect against this seal virus, meaning a new vaccine would be necessary if there ever was an outbreak in humans.
"The ability to transmit through the air is an important step in the path toward any influenza virus becoming pandemic," said USGS scientist Hon Ip. "The lack of protection against the seal virus from the annual seasonal vaccine highlights the risks posed by this H3N8 group of viruses."
The article, led by St. Jude in collaboration with the USGS and the University of North Carolina at Chapel Hill, was published today in the journal Nature Communications and is available online.
The scientists tested a sample of the influenza virus taken from an infected harbor seal in New Hampshire in 2011, and found that the virus was closely related to inﬂuenza viruses from wild birds. However, the H3N8 virus isolated from the seal contained mutations that allowed it to reproduce efficiently in human lung cells, cause disease in mice and infect ferrets through the air.
"Findings from this study highlight the need for continued surveillance and study of avian influenza genetics, particularly in areas like coastal regions where wild birds, wild mammals and human populations come into contact with each other,” said USGS scientist Jeff Hall.
H3N8 viruses, common in wild birds, have been associated with ongoing outbreaks in dogs and horses and have also been detected in pigs, donkeys and now seals. Beginning in September 2011, more than 160 young harbor seals were found dead or dying along the New England coast as a result of this infection. In previous H3N8 mortality events, up to 20 percent of the local seal population died.
For more information on zoonotic diseases, or diseases that spread between animals and humans, please visit the USGS National Wildlife Health Center website.