Airport geomagnetic surveys in the United States
A. Berarducci
2006, NATO Security through Science Series C: Environmental Security 247-258
The Federal Aviation Administration (FAA) and the United States military have requirements for design, location, and construction of compass calibration pads (compass roses), these having been developed through collaboration with US Geological Survey (USGS) personnel. These requirements are detailed in the FAA Advisory Circular AC 150/5300-13, Appendix 4, and in...
Spatial and temporal patterns of wildfires in the Mojave Desert, 1980-2004
M.L. Brooks, J.R. Matchett
2006, Journal of Arid Environments (67) 148-164
Fire has been historically infrequent in the Mojave Desert, and its increased prevalence caused by the invasion of non-native annual grasses is a major concern for land managers there. The most dramatic changes have occurred in middle elevation shrublands dominated by creosotebush (Larrea tridentata), Joshua tree (Yucca brevifolia), and/or blackbrush...
Sampling blood from big brown bats (Eptesicus fuscus) in the field with and without anesthesia: Impacts on survival
L.E. Ellison, T. J. O'Shea, J. Wimsatt, R.D. Pearce, D.J. Neubaum, M.A. Neubaum, R. A. Bowen
2006, Journal of Wildlife Diseases (42) 849-852
Blood was collected from wild big brown bats (Eptesicus fuscus) with and without anesthesia in Fort Collins, Colorado in 2004 to assess the impacts of these procedures on short-term survival and 1-yr return rates. Short-term survival and 1-yr return rates after release were passively monitored using PIT tag detection hoops...
San Andreas fault geometry in the Parkfield, California, region
R.W. Simpson, M. Barall, J. Langbein, J.R. Murray, M. J. Rymer
2006, Bulletin of the Seismological Society of America (96)
In map view, aftershocks of the 2004 Parkfield earthquake lie along a line that forms a straighter connection between San Andreas fault segments north and south of the Parkfield reach than does the mapped trace of the fault itself. A straightedge laid on a geologic map of Central California reveals...
Fate of fish production in a seasonally flooded saltmarsh
Philip W. Stevens, C.L. Montague, K. J. Sulak
2006, Marine Ecology Progress Series (327) 267-277
Although saltmarshes are thought to enhance the productivity of open estuarine waters, the mechanism by which energy transfer occurs has been debated for decades. One possible mechanism is the transfer of saltmarsh production to estuarine waters by vagile fishes and invertebrates. Monthly estimates of fish standing stock, net fish ingress,...
Do migratory flight paths of raptors follow constant geographical or geomagnetic courses?
K. Thorup, M. Fuller, T. Alerstam, M. Hake, N. Kjellen, R. Strandberg
2006, Animal Behaviour (72) 875-880
We tested whether routes of raptors migrating over areas with homogeneous topography follow constant geomagnetic courses more or less closely than constant geographical courses. We analysed the routes taken over land of 45 individual raptors tracked by satellite-based radiotelemetry: 25 peregrine falcons, Falco peregrinus, on autumn migration between North and...
Quantitative analysis of scale of aeromagnetic data raises questions about geologic-map scale
V. Nykanen, G. L. Raines
2006, Natural Resources Research (15) 213-222
A recently published study has shown that small-scale geologic map data can reproduce mineral assessments made with considerably larger scale data. This result contradicts conventional wisdom about the importance of scale in mineral exploration, at least for regional studies. In order to formally investigate aspects of scale, a weights-of-evidence analysis...
Global phylogeographic limits of Hawaii's avian malaria
J.S. Beadell, F. Ishtiaq, R. Covas, M. Melo, B.H. Warren, C. T. Atkinson, S. Bensch, G.R. Graves, Y.V. Jhala, M.A. Peirce, A.R. Rahmani, D.M. Fonseca, R.C. Fleischer
2006, Proceedings of the Royal Society B: Biological Sciences (273) 2935-2944
The introduction of avian malaria (Plasmodium relictum) to Hawaii has provided a model system for studying the influence of exotic disease on naive host populations. Little is known, however, about the origin or the genetic variation of Hawaii's malaria and traditional classification methods have confounded attempts to place the parasite...
Evaluation of aerial survey methods for Dall's sheep
Mark S. Udevitz, Brad S. Shults, Layne G. Adams, Christopher Kleckner
2006, Wildlife Society Bulletin (34) 732-740
Most Dall's sheep (Ovis dalli dalli) population-monitoring efforts use intensive aerial surveys with no attempt to estimate variance or adjust for potential sightability bias. We used radiocollared sheep to assess factors that could affect sightability of Dall's sheep in standard fixed-wing and helicopter surveys and to evaluate feasibility of methods...
Pigs on the plains: Institutional analysis of a Colorado water quality initiative
D. King, N. Burkardt, Lamb B. Lee
2006, International Journal of Public Administration (29) 1411-1430
We used the Legal-Institutional Analysis Model (LIAM) and Advocacy Coalition Framework (ACF) to analyze the campaign over passage of the Colorado Hogs Rule, an initiative passed by the voters in 1998 to require regulation of swine production facilities in Colorado. Used in tandem, LIAM and ACF provided an opportunity to...
Coseismic and postseismic slip of the 2004 Parkfield earthquake from space-geodetic data
I.A. Johanson, E.J. Fielding, F. Rolandone, R. Burgmann
2006, Bulletin of the Seismological Society of America (96)
We invert interferometric synthetic aperture radar (InSAR) data jointly with campaign and continuous global positioning system (GPS) data for slip in the coseismic and postseismic periods of the 2004 Parkfield earthquake. The InSAR dataset consists of eight interferograms from data collected by the Envisat and Radarsat satellites spanning the time...
Survival and growth of age-0 steelhead after surgical implantation of 23-mm passive integrated transponders
D.S. Bateman, R. E. Gresswell
2006, North American Journal of Fisheries Management (26) 545-550
Little information is available on the effects of implanting 23-mm passive integrated transponder (PIT) tags in salmonids less than 90 mm fork length (FL). Using juvenile steelhead Oncorhynchus mykiss (range, 73–97 mm FL), we compared instantaneous growth rates and survival among three experimental groups: control, surgery with no tag, and surgery with...
Spatial correlation of shear-wave velocity within San Francisco Bay Sediments
E.M. Thompson, L.G. Baise, R. E. Kayen
2006, Conference Paper, GeoCongress 2006: Geotechnical Engineering in the Information Technology Age
Sediment properties are spatially variable at all scales, and this variability at smaller scales influences high frequency ground motions. We show that surface shear-wave velocity is highly correlated within San Francisco Bay Area sediments using shear-wave velocity measurements from 210 seismic cone penetration tests. We use this correlation to estimate...
Prevalence of Microsporidia, Cryptosporidium spp., and Giardia spp. in beavers (Castor canadensis) in Massachusetts
R. Fayer, M. Santin, J.M. Trout, S. DeStefano, K. Koenen, T. Kaur
2006, Journal of Zoo and Wildlife Medicine (37) 492-497
Feces from 62 beavers (Castor canadensis) in Massachusetts were examined by fluorescence microscopy (IFA) and polymerase chain reaction (PCR) for Microsporidia species, Cryptosporidium spp., and Giardia spp. between January 2002 and December 2004. PCR-positive specimens were further examined by gene sequencing. Protist parasites were detected in 6.4% of the beavers....
Uranium distribution in the coastal waters and pore waters of Tampa Bay, Florida
P.W. Swarzenski, M. Baskaran
2006, Marine Chemistry (102) 252-266
The geochemical reactivity of uranium (238U) and dissolved organic carbon (DOC), Fe, Mn, Ba, and V was investigated in the water column, pore waters, and across a river/estuarine mixing zone in Tampa Bay, Florida. This large estuary is impacted both by diverse anthropogenic activity and by extensive U-rich phosphatic deposits....
Transport of horseshoe crab eggs by waves and swash on an estuarine beach: Implications for foraging shorebirds
K.F. Nordstrom, N.L. Jackson, D. R. Smith, R.G. Weber
2006, Estuarine, Coastal and Shelf Science (70) 438-448
The abundance of horseshoe crab eggs in the swash zone and remaining on the beach after tide levels fall was evaluated to identify how numbers of eggs available to shorebirds differ with fluctuations in spawning numbers of horseshoe crabs, wave energies and beach elevation changes. Field data were gathered 1-6...
The influence of aridity and fire on Holocene prairie communities in the eastern Prairie Peninsula
D.M. Nelson, S.H. Feng, E.C. Grimm, B. Brandon Curry, J.E. Slate
2006, Ecology (87) 2523-2536
The role of climate and fire in the development, maintenance, and species composition of prairie in the eastern axis of the tallgrass Prairie Peninsula intrigued early North American ecologists. However, evaluation of the long-standing hypotheses about the region's environmental history has been hampered by the scarcity of paleorecords. We conducted...
A new Lagerstätte from the Middle Ordovician St. Peter formation in northeast Iowa, USA
Huaibao P. Liu, Robert M. McKay, Jean N. Young, Brian J. Witzke, Kathlyn J. McVey, Xiuying Liu
2006, Geology (34) 969-972
A new fossil fauna has been discovered from a recently recognized shale unit within the middle Ordovician St. Peter Formation in northeast Iowa. It contains a variety of invertebrates and vertebrates, including soft body tissues, impressions, and 3-dimensionalpreservations. The exceptional preservation reveals a new Konservat-Lagerstätte, the Winneshiek Lagerstätte, and opens...
Ecology of a population of subsidized predators: Common ravens in the central Mojave Desert, California
W.I. Boarman, M.A. Patten, R.J. Camp, S.J. Collis
2006, Journal of Arid Environments (67) 248-261
Human subsidies have resulted in the rapid growth of populations of common ravens (Corvus corax) in the Mojave Desert. This is a management concern because ravens prey on threatened desert tortoises (Gopherus agassizii). We conducted weekly counts for 29 months at 10 sites on the US Army's National Training Center,...
Cloud-to-ground lightning and surface rainfall in warm-season Florida thunderstorms
B. Gungle, E.P. Krider
2006, Journal of Geophysical Research D: Atmospheres (111)
Relationships between cloud-to-ground (CG) lightning and surface rainfall have been examined in nine isolated, warm-season thunderstorms on the east coast of central Florida. CG flashes and the associated rain volumes were measured as a function of time in storm-centered reference frames that followed each storm over a network of rain...
Sulfates on Mars: A systematic Raman spectroscopic study of hydration states of magnesium sulfates
A. Wang, J.J. Freeman, B.L. Jolliff, I.-M. Chou
2006, Geochimica et Cosmochimica Acta (70) 6118-6135
The martian orbital and landed surface missions, OMEGA on Mar Express and the two Mars Explorations Rovers, respectively, have yielded evidence pointing to the presence of magnesium sulfates on the martian surface. In situ identification of the hydration states of magnesium sulfates, as well as the hydration states of other...
Shrinking ponds in subarctic Alaska based on 1950-2002 remotely sensed images
B. Riordan, D. Verbyla, A. D. McGuire
2006, Journal of Geophysical Research G: Biogeosciences (111)
Over the past 50 years, Alaska has experienced a warming climate with longer growing seasons, increased potential evapotranspiration, and permafrost warming. Research from the Seward Peninsula and Kenai Peninsula has demonstrated a substantial landscape-level trend in the reduction of surface water and number of closed-basin ponds. We investigated whether this...
Attributes of desert tortoise populations at the National Training Center, Central Mojave Desert, California, USA
K.H. Berry, T.Y. Bailey, K.M. Anderson
2006, Journal of Arid Environments (67) 165-191
We sampled 21 study plots for desert tortoises (Gopherus agassizii) at the National Training Center, Fort Irwin, California. Each plot was sampled once between 1997 and 2003 to obtain a snapshot of population attributes, status, and relationships between tortoise densities and human activities. Densities ranged from <1 to 28 tortoises...
Correlated growth and survival of juvenile spectacled eiders: Evidence of habitat limitation?
Paul L. Flint, Julie A. Morse, J. Barry Grand, Christine L. Moran
2006, The Condor (108) 901-911
We studied the growth and survival of Spectacled Eider (Somateria fischeri) ducklings to 30 days of age along the lower Kashunuk River on the Yukon-Kuskokwim Delta from 1995 to 2000. We replicated this study at a second site, Kigigak Island, in 1999 and 2000. Age-adjusted estimates of duckling mass and...
The origin of neap-spring tidal cycles
E.P. Kvale
2006, Marine Geology (235) 5-18
The origin of oceanic tides is a basic concept taught in most introductory college-level sedimentology/geology, oceanography, and astronomy courses. Tides are typically explained in the context of the equilibrium tidal theory model. Yet this model does not take into account real tides in many parts of the world. Not only...
