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- Amphibian decline (3)
- Amphibian declines (2)
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Articles 1 - 30 of 40
Full-Text Articles in Physical Sciences and Mathematics
Mountain Plover Population Responses To Black-Tailed Prairie Dogs In Montana, Stephen J. Dinsmore, Gary C. White, Fritz L. Knopf
Mountain Plover Population Responses To Black-Tailed Prairie Dogs In Montana, Stephen J. Dinsmore, Gary C. White, Fritz L. Knopf
United States Geological Survey: Staff Publications
We studied a local population of mountain plovers (Charadrius montanus) in southern Phillips County, Montana, USA, from 1995 to 2000 to estimate annual rates of recruitment rate (f) and population change (λ). We used Pradel models, and we modeled λ as a constant across years, as a linear time trend, as year-specific, and with an additive effect of area occupied by prairie dogs (Cynomys ludovicianus). We modeled recruitment rate (f) as a function of area occupied by prairie dogs with the remaining model structure identical to the best model used to estimate λ. Our results indicated …
Nonlinear Dynamics In Ecosystem Response To Climatic Change: Case Studies And Policy Implications, Virginia R. Burkett, Douglas A. Wilcox, Wilcox Stottlemyer, Wylie Barrow, Dan Fagre, Jill Baron, Jeff Price, Jennifer L. Nielsen, Craig D. Allen, David L. Peterson, Greg Ruggerone, Thomas Doyle
Nonlinear Dynamics In Ecosystem Response To Climatic Change: Case Studies And Policy Implications, Virginia R. Burkett, Douglas A. Wilcox, Wilcox Stottlemyer, Wylie Barrow, Dan Fagre, Jill Baron, Jeff Price, Jennifer L. Nielsen, Craig D. Allen, David L. Peterson, Greg Ruggerone, Thomas Doyle
United States Geological Survey: Staff Publications
Many biological, hydrological, and geological processes are interactively linked in ecosystems. These ecological phenomena normally vary within bounded ranges, but rapid, nonlinear changes to markedly different conditions can be triggered by even small differences if threshold values are exceeded. Intrinsic and extrinsic ecological thresholds can lead to effects that cascade among systems, precluding accurate modeling and prediction of system response to climate change. Ten case studies from North America illustrate how changes in climate can lead to rapid, threshold-type responses within ecological communities; the case studies also highlight the role of human activities that alter the rate or direction of …
The Impacts Of Sprawl On Biodiversity: The Ant Fauna Of The Lower Florida Keys, Elizabeth A. Forys, Craig R. Allen
The Impacts Of Sprawl On Biodiversity: The Ant Fauna Of The Lower Florida Keys, Elizabeth A. Forys, Craig R. Allen
United States Geological Survey: Staff Publications
Sprawling development can affect species composition by increasing the rate of invasion by non-native species, and decreasing the persistence of native species. This paper briefly reviews the scientific literature on the impacts of sprawl on biological diversity, with specific emphasis on the influence of sprawl on non-native species richness. We then explore the relationship between sprawl and biodiversity using a data set of ant species collected from 46 habitat patches located in the increasingly suburbanized Florida Keys, USA. We quantified sprawl as the proximity of roads and amount of development surrounding a habitat patch. Using bait transects, we identified 24 …
Estimated Ultraviolet Radiation Doses In Wetlands In Six National Parks, Stephen A. Diamond, Peter C. Trenham, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Stacey L. Stark, David Bradford, P. Stephen Corn, Ken Czarnowski, Paul D. Brooks, Dan Fagre, Bob Breen, Naomi E. Detenbeck, Kathy Tonnessen
Estimated Ultraviolet Radiation Doses In Wetlands In Six National Parks, Stephen A. Diamond, Peter C. Trenham, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Stacey L. Stark, David Bradford, P. Stephen Corn, Ken Czarnowski, Paul D. Brooks, Dan Fagre, Bob Breen, Naomi E. Detenbeck, Kathy Tonnessen
United States Geological Survey: Staff Publications
Ultraviolet-B radiation (UV-B, 280–320-nm wavelengths) doses were estimated for 1024 wetlands in six national parks: Acadia (Acadia), Glacier (Glacier), Great Smoky Mountains (Smoky), Olympic (Olympic), Rocky Mountain (Rocky), and Sequoia/ Kings Canyon (Sequoia). Estimates were made using ground-based UV-B data (Brewer spectrophotometers), solar radiation models, GIS tools, field characterization of vegetative features, and quantification of DOC concentration and spectral absorbance. UV-B dose estimates were made for the summer solstice, at a depth of 1 cm in each wetland. The mean dose across all wetlands and parks was 19.3 W-h m-2 (range of 3.4–32.1 W-h m-2). The mean …
Distribution Patterns Of Lentic-Breeding Amphibians In Relation To Ultraviolet Radiation Exposure In Western North America, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Paul Stephen Corn, Stephen A. Diamond, Peter C. Trenham, Dan B. Fagre
Distribution Patterns Of Lentic-Breeding Amphibians In Relation To Ultraviolet Radiation Exposure In Western North America, Michael J. Adams, Blake R. Hossack, Roland A. Knapp, Paul Stephen Corn, Stephen A. Diamond, Peter C. Trenham, Dan B. Fagre
United States Geological Survey: Staff Publications
An increase in ultraviolet-B (UV-B) radiation has been posited to be a potential factor in the decline of some amphibian population. This hypothesis has received support from laboratory and field experiments showing that current levels of UV-B can cause embryo mortality in some species, but little research has addressed whether UV-B is influencing the distribution of amphibian populations. We compared patterns of amphibian presence to sitespecific estimates of UV-B dose at 683 ponds and lakes in Glacier, Olympic, and Sequoia–Kings Canyon National Parks. All three parks are located in western North America, a region with a concentration of documented amphibian …
Patterns Of Fish Use And Piscivore Abundance Within A Reconnected Saltmarsh Impoundment In The Northern Indian River Lagoon, Florida, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak
Patterns Of Fish Use And Piscivore Abundance Within A Reconnected Saltmarsh Impoundment In The Northern Indian River Lagoon, Florida, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak
United States Geological Survey: Staff Publications
Nearly all saltmarshes in east-central, Florida were impounded for mosquito control during the 1960s. The majority of these marshes have since been reconnected to the estuary by culverts, providing an opportunity to effectively measure exchange of aquatic organisms. A multi-gear approach was used monthly to simultaneously estimate fish standing stock (cast net), fish exchange with the estuary (culvert traps), and piscivore abundance (gill nets and bird counts) to document patterns of fish use in a reconnected saltmarsh impoundment. Changes in saltmarsh fish abundance, and exchange of fish with the estuary reflected the seasonal pattern of marsh flooding in the northern …
Lack Of Significant Changes In The Herpetofauna Of Theodore Roosevelt National Park, North Dakota, Since The 1920s, Blake R. Hossack, Paul Stephen Corn, David S. Pilliod
Lack Of Significant Changes In The Herpetofauna Of Theodore Roosevelt National Park, North Dakota, Since The 1920s, Blake R. Hossack, Paul Stephen Corn, David S. Pilliod
United States Geological Survey: Staff Publications
We surveyed 88 upland wetlands and 12 1-km river sections for amphibians in Theodore Roosevelt National Park, North Dakota, during 2001–2002 to gather baseline data for future monitoring efforts and to evaluate changes in the distribution of species. We compared our results to collections of herpetofauna made during 1920–1922, 1954 and 1978–1979. The boreal chorus frog (Pseudacris maculata) was the most common amphibian in upland wetlands, followed by the tiger salamander (Ambystoma tigrinum), Woodhouse’s toad (Bufo woodhousii), northern leopard frog (Rana pipiens), plains spadefoot (Spea bombifrons) and the Great Plains …
Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree
Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree
United States Geological Survey: Staff Publications
In Nebraska, a large number (>200) of shallow sand-point and cased wells completed in coarse alluvial sediments along rivers and lakes still are used to obtain drinking water for human consumption, even though construction of sand-point wells for consumptive uses has been banned since 1987. The quality of water from shallow domestic wells potentially vulnerable to seepage from septic systems was evaluated by analyzing for the presence of tracers and multiple isotopes. Samples were collected from 26 sand-point and perforated, cased domestic wells and were analyzed for bacteria, coliphages, nitrogen species, nitrogen and boron isotopes, dissolved organic carbon (DOC), …
The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak
The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak
United States Geological Survey: Staff Publications
The existing scientific literature on offshore benthic assemblages (OBA) residing along the US East and Gulf of Mexico continental shelf was reviewed. Identification was made of any associations between the dominant OBA and particular sediment types and/or bathymetry. Of special interest was the evaluation of reported effects of sand dredge/mining activities on the dominant OBA and recognition of data deficiencies. One hundred and twenty-two references were selected and classified as to type of study with pertinent results extracted. Polychaetes were predominantly cited as the principal infaunal taxa present in studies from both the Gulf of Mexico and US Atlantic coast. …
Amphibian Research And Monitoring Initiative (Armi): A Successful Start To A National Program In The United States, Erin Muths, Robin E. Jung, Larissa L. Bailey, Michael J. Adams, P. Stephen Corn, C. Kenneth Dodd Jr., Gary M. Fellers, Walter J. Sadinski, Cecil R. Schwalbe, Susan C. Walls, Robert N. Fisher, Alisa L. Gallant, William A. Battaglin, D. Earl Green
Amphibian Research And Monitoring Initiative (Armi): A Successful Start To A National Program In The United States, Erin Muths, Robin E. Jung, Larissa L. Bailey, Michael J. Adams, P. Stephen Corn, C. Kenneth Dodd Jr., Gary M. Fellers, Walter J. Sadinski, Cecil R. Schwalbe, Susan C. Walls, Robert N. Fisher, Alisa L. Gallant, William A. Battaglin, D. Earl Green
United States Geological Survey: Staff Publications
Most research to assess amphibian declines has focused on local-scale projects on one or a few species. The Amphibian Research and Monitoring Initiative (ARMI) is a national program in the United States mandated by congressional directive and implemented by the U.S. Department of the Interior (specifically the U.S. Geological Survey, USGS). Program goals are to monitor changes in populations of amphibians across U.S. Department of the Interior lands and to address research questions related to amphibian declines using a hierarchical framework of base-, mid- and apex-level monitoring sites. ARMI is currently monitoring 83 amphibian species (29% of species in the …
Late-Holocene Flooding And Drought In The Northern Great Plains, Usa, Reconstructed From Tree Rings, Lake Sediments And Ancient Shorelines, M. D. Shapley, W. C. Johnson, D. R. Engstrom, W. R. Osterkamp
Late-Holocene Flooding And Drought In The Northern Great Plains, Usa, Reconstructed From Tree Rings, Lake Sediments And Ancient Shorelines, M. D. Shapley, W. C. Johnson, D. R. Engstrom, W. R. Osterkamp
United States Geological Survey: Staff Publications
During the AD 1990s the Waubay Lakes complex in eastern South Dakota experienced historically unprecedented high water levels. Property damage from this flooding led to an examination of the occurrence of past pluvial episodes and their relation to climate. A lOOO-year hydroclimate reconstruction was developed from local bur oak (Quercus macrocarpa) tree-ring records and lake-sediment cores. Analysis of lake shoreline and drainage features provides late-Quaternary geomorphic context for this high-resolution record. Tree-ring width and shell geochemistry of the ostracode Candona rawsoni show marked coherence, indicating synchronous responses to moisture balance in vegetation and lake salinity; geomorphic evidence …
Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling
Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling
United States Geological Survey: Staff Publications
The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …
Acquisition And Evaluation Of Thermodynamic Data For Bieberite-Moorhouseite Equilibria At 0.1 Mpa, I-Ming Chou, Robert Seal Ii
Acquisition And Evaluation Of Thermodynamic Data For Bieberite-Moorhouseite Equilibria At 0.1 Mpa, I-Ming Chou, Robert Seal Ii
United States Geological Survey: Staff Publications
Published estimates for the equilibrium relative humidity (RH) at 25 °C for the reaction: bieberite (CoSO4•7H2O) = moorhouseite (CoSO4•6H2O) + H2O, range from 69.8 to 74.5%. To evaluate these data, the humidity-buffer technique was used to determine equilibrium constants for this reaction between 14 and 43 °C at 0.1 MPa. Reversals along fi ve humidity-buffer curves yield ln K = 18.03–6509.43/T, where K is the equilibrium constant, and T is temperature in K. The derived standard Gibbs free energy of reaction is 9.43 kJ/mol, which agrees well with several previously …
Geochemistry Of Sulfate Minerals In High- And Low-Temperature Environments: A Tribute To Robert O. Rye, Robert R. Seal Ii, John L. Jambor, Charles N. Alpers
Geochemistry Of Sulfate Minerals In High- And Low-Temperature Environments: A Tribute To Robert O. Rye, Robert R. Seal Ii, John L. Jambor, Charles N. Alpers
United States Geological Survey: Staff Publications
This special issue is a tribute to Robert O. Rye, known as "Bob" to most, in light of his highly productive and ongoing career. Almost all of the papers in this issue are derived from topical sessions on sulfate minerals in hydrothermal and low-temperature environments. The sessions, held at the 2000 Geological Society of America meeting in Reno, NV, and sponsored jointly by the Mineralogical Society of America, the Society of Economic Geologists and the Geochemical Society, included 29 oral and 9 poster presentations. The sessions complemented a short course on the crystallography, geochemistry and environmental significance of sulfate minerals, …
Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhalla, Charles N. Alpers, Gregg A. Swayze
Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhalla, Charles N. Alpers, Gregg A. Swayze
United States Geological Survey: Staff Publications
Prior to remediation at the abandoned Cu–Zn Penn Mine in the Foothills massive sulfide belt of the Sierra Nevada, CA, acid mine drainage (AMD) was created, in part, by the subaerial oxidation of sulfides exposed on several waste piles. To support remediation efforts, a mineralogical study of the waste piles was undertaken by acquiring reflectance spectra (measured in the visible to short-wave infrared range of light (0.35–2.5 μm) using a portable, digitally integrated pen tablet PC mapping system with differential global positioning system and laser rangefinder support. Analysis of the spectral data made use of a continuum removal and band-shape …
Selenium Impactson Razorback Sucker, Colorado River, Colorado I. Adults, Steven J. Hamilton, Kathy M. Holley, Kevin J. Buhl, Fern A. Bullard, L. Ken Weston, Susan F. Mcdonald
Selenium Impactson Razorback Sucker, Colorado River, Colorado I. Adults, Steven J. Hamilton, Kathy M. Holley, Kevin J. Buhl, Fern A. Bullard, L. Ken Weston, Susan F. Mcdonald
United States Geological Survey: Staff Publications
Adult razorback sucker (Xyrauchen texanus) were exposed to various selenium concentrations in ponds and isolated river channels of the Colorado River near Grand Junction, CO, to determine effectson their growth and residue accumulation over an 11-month period. Adults at Horsethief ponds were fed a commercial diet, whereas fish at Adobe Creek channel and North Pond foraged on natural food items. Selenium concentrations at Horsethief were 2.2 μg/L in water, 0.1–1.4 μg/g in sediment, and 2.3–3.1 μg/g in food organisms (1.1 μg/g in commercial fish food), at Adobe Creek were 3.8 μg/L in water, 0.5–2.1 μg/g in sediment, and …
Temporal Analysis Of The Frequency And Duration Of Low And High Streamflow: Years Of Record Needed To Characterize Streamflow Variability, Seungho Huh, David A. Dickey, M. R. Meador, K. E. Ruhl
Temporal Analysis Of The Frequency And Duration Of Low And High Streamflow: Years Of Record Needed To Characterize Streamflow Variability, Seungho Huh, David A. Dickey, M. R. Meador, K. E. Ruhl
United States Geological Survey: Staff Publications
A temporal analysis of the number and duration of exceedences of high- and low-flow thresholds was conducted to determine the number of years required to detect a level shift using data from Virginia, North Carolina, and South Carolina. Two methods were used—ordinary least squares assuming a known error variance and generalized least squares without a known error variance. Using ordinary least squares, the mean number of years required to detect a one standard deviation level shift in measures of low-flow variability was 57.2 (28.6 on either side of the break), compared to 40.0 years for measures of high-flow variability. These …
The Composition Of Coexisting Jarosite-Group Minerals And Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, D. Kirk Nordstrom, Alexei Poustovetov, Heather A. Lowers
The Composition Of Coexisting Jarosite-Group Minerals And Water From The Richmond Mine, Iron Mountain, California, Heather E. Jamieson, Clare Robinson, Charles N. Alpers, D. Kirk Nordstrom, Alexei Poustovetov, Heather A. Lowers
United States Geological Survey: Staff Publications
Jarosite-group minerals accumulate in the form of stalactites and fine-grained mud on massive pyrite in the D drift of the Richmond mine, Iron Mountain, California. Water samples were collected by placing beakers under the dripping stalactites and by extracting pore water from the mud using a centrifuge. The water is rich in Fe3+ and SO42–, with a pH of approximately 2.1, which is significantly higher than the extremely acidic waters found elsewhere in the mine. Electron-microprobe analysis and X-ray mapping indicate that the small crystals (<10 μm in diameter) are compositionally zoned with respect to Na and K, and include hydronium jarosite corresponding to the formula (H3O)0.6K0.3Na0.1Fe3+3 …
Conceptual Model Of Sediment Processes In The Upper Yuba River Watershed, Sierra Nevada, Ca, Jennifer A. Curtis, Lorraine E. Flint, Charles N. Alpers, Sarah M. Yarnell
Conceptual Model Of Sediment Processes In The Upper Yuba River Watershed, Sierra Nevada, Ca, Jennifer A. Curtis, Lorraine E. Flint, Charles N. Alpers, Sarah M. Yarnell
United States Geological Survey: Staff Publications
This study examines the development of a conceptual model of sediment processes in the upper Yuba River watershed; and we hypothesize how components of the conceptual model may be spatially distributed using a geographical information system (GIS). The conceptual model illustrates key processes controlling sediment dynamics in the upper Yuba River watershed and was tested and revised using field measurements, aerial photography, and low elevation videography. Field reconnaissance included mass wasting and channel storage inventories, assessment of annual channel change in upland tributaries, and evaluation of the relative importance of sediment sources and transport processes. Hillslope erosion rates throughout the …
U-Pb Zircon Ages And Pb Isotope Geochemistry Of Gold Deposits In The Carolina Slate Belt Of South Carolina, R. A. Ayuso, J. L. Wooden, N. K. Foley, Robert R. Seal Ii, A. K. Sinha
U-Pb Zircon Ages And Pb Isotope Geochemistry Of Gold Deposits In The Carolina Slate Belt Of South Carolina, R. A. Ayuso, J. L. Wooden, N. K. Foley, Robert R. Seal Ii, A. K. Sinha
United States Geological Survey: Staff Publications
Volcanic rocks of the Persimmon Fork Formation host the largest known gold mines of the Carolina slate belt. U-Pb (SHRIMP) zircon ages have been obtained from rocks closely associated with pyrite-enargite-gold deposits at Brewer (quartz-topaz rhyolite breccia from the argillic alteration zone in the Brewer pit and felsic ash-flow tuff from the quartz sericite alteration zone), from the disseminated and semimassive pyrite-gold deposits at Haile (crystal lithic rhyolitic ash-flow tuffs from the Champion pit), and from the Ridgeway deposit (felsic ash-flow tuff from the stratigraphic host of the North pit gold deposit). Generally, the zircons are fine grained, fractured, and …
A Multilocus Population Genetic Survey Of The Greater Sage-Grouse Across Their Range, S. J. Oyler-Mccance, S.E. Taylor, T. W. Quinn
A Multilocus Population Genetic Survey Of The Greater Sage-Grouse Across Their Range, S. J. Oyler-Mccance, S.E. Taylor, T. W. Quinn
United States Geological Survey: Staff Publications
The distribution and abundance of the greater sage-grouse (Centrocercus urophasianus) have declined dramatically, and as a result the species has become the focus of conservation efforts. We conducted a range-wide genetic survey of the species which included 46 populations and over 1000 individuals using both mitochondria1 sequence data and data from seven nuclear microsatellites. Nested clade and STRUCTURE analyses revealed that, in general, the greater sage-grouse populations follow an isolation-by-distance model of restricted gene flow. This suggests that movements of the greater sage-grouse are typically among neighboring populations and not across the species, range. This may have important …
Climate Change And Amphibians, P.S. Corn
Climate Change And Amphibians, P.S. Corn
United States Geological Survey: Staff Publications
Amphibian life histories are exceedingly sensitive to temperature and precipitation, and there is good evidence that recent climate change has already resulted in a shift to breeding earlier in the year for some species. There are also suggestions that the recent increase in the occurrence of El Niño events has caused declines of anurans in Central America and is linked to elevated mortality of amphibian embryos in the northwestern United States. However, evidence linking amphibian declines in Central America to climate relies solely on correlations, and the mechanisms underlying the declines are not understood. Connections between embryo mortality and declines …
Topographic, Bioclimatic, And Vegetation Characteristics Of Three Ecoregion Classification Systems In North America: Comparisons Along Continent-Wide Transects, Robert Thompson, Sarah Shafer, Katherine Anderson, Laura Strickland, Richard Pelltier, Patrick Bartlein, Michael Kerwin
Topographic, Bioclimatic, And Vegetation Characteristics Of Three Ecoregion Classification Systems In North America: Comparisons Along Continent-Wide Transects, Robert Thompson, Sarah Shafer, Katherine Anderson, Laura Strickland, Richard Pelltier, Patrick Bartlein, Michael Kerwin
United States Geological Survey: Staff Publications
Ecoregion classification systems are increasingly used for policy and management decisions, particularly among conservation and natural resource managers. A number of ecoregion classification systems are currently available, with each system defining ecoregions using different classification methods and different types of data. As a result, each classification system describes a unique set of ecoregions. To help potential users choose the most appropriate ecoregion system for their particular application, we used three latitudinal transects across North America to compare the boundaries and environmental characteristics of three ecoregion classification systems [Küchler, World Wildlife Fund (WWF), and Bailey]. A variety of variables were used …
An Evaluation Of Weather And Disease As Causes Of Decline In Two Populations Of Boreal Toads, Rick D. Scherer, Erin Muths, Barry R. Noon, Paul Stephen Corn
An Evaluation Of Weather And Disease As Causes Of Decline In Two Populations Of Boreal Toads, Rick D. Scherer, Erin Muths, Barry R. Noon, Paul Stephen Corn
United States Geological Survey: Staff Publications
Two populations of boreal toads (Bufo boreas) experienced drastic declines in abundance in the late 1990s. Evidence supported the hypothesis of disease (the chytrid fungus, Batrachochytrium dendrobatidis) as the cause of these declines. but other hypotheses had not been evaluated. We used an 11-year capture-recapture data set to evaluate weather and disease as causes of these declines. We developed sets of mathematical models that reflected hypothesized relationships between several weather variables and annual survival rates of adult males in these populations. In addition, models that reflected the possibility that the declines were caused by an introduced fungus …
Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins
Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins
United States Geological Survey: Staff Publications
Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, …
Comparison Of A Novel Passive Sampler To Standard Water-Column Sampling For Organic Contaminants Associated With Wastewater Effluents Entering A New Jersey Stream, D. A. Alvarez, P. E. Stackelberg, J. D. Petty, J. N. Huckins, E. T. Furlong, S. D. Zaugg, M. T. Meyer
Comparison Of A Novel Passive Sampler To Standard Water-Column Sampling For Organic Contaminants Associated With Wastewater Effluents Entering A New Jersey Stream, D. A. Alvarez, P. E. Stackelberg, J. D. Petty, J. N. Huckins, E. T. Furlong, S. D. Zaugg, M. T. Meyer
United States Geological Survey: Staff Publications
Four water samples collected using standard depth and width water-column sampling methodology were compared to an innovative passive, in situ, sampler (the polar organic chemical integrative sampler or POCIS) for the detection of 96 organic wastewater-related contaminants (OWCs) in a stream that receives agricultural, municipal, and industrial wastewaters. Thirty-two OWCs were identified in POCIS extracts whereas 9–24 were identified in individual water-column samples demonstrating the utility of POCIS for identifying contaminants whose occurrence are transient or whose concentrations are below routine analytical detection limits. Overall, 10 OWCs were identified exclusively in the POCIS extracts and only six solely identified in …
Paleontology And Stratigraphy Of Upper Coniacianemiddle Santonian Ammonite Zones And Application To Erosion Surfaces And Marine Transgressive Strata In Montana And Alberta, W. A. Cobban, T. S. Dyman, K. W. Porter
Paleontology And Stratigraphy Of Upper Coniacianemiddle Santonian Ammonite Zones And Application To Erosion Surfaces And Marine Transgressive Strata In Montana And Alberta, W. A. Cobban, T. S. Dyman, K. W. Porter
United States Geological Survey: Staff Publications
Erosional surfaces are present in middle and upper Coniacian rocks in Montana and Alberta, and probably at the base of the middle Santonian in the Western Interior of Canada. These erosional surfaces are biostratigraphically constrained using inoceramid bivalves and ammonites, which are used to define lower, middle, and upper substages of both the Coniacian and Santonian stages of the Upper Cretaceous in this region. The most detailed biostratigraphy associated with these erosional surfaces concerns the MacGowan Concretionary Bed in the Kevin Member of the Marias River Shale in Montana, where the bed lies disconformably on middle or lowermost upper Coniacian …
Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhall, Charles N. Alpers, Gregg A. Swayze
Characterization Of Waste Rock Associated With Acid Drainage At The Penn Mine, California, By Ground-Based Visible To Short-Wave Infrared Reflectance Spectroscopy Assisted By Digital Mapping, Irene C. Montero S., George H. Brimhall, Charles N. Alpers, Gregg A. Swayze
United States Geological Survey: Staff Publications
Prior to remediation at the abandoned Cu–Zn Penn Mine in the Foothills massive sulfide belt of the Sierra Nevada, CA, acid mine drainage (AMD) was created, in part, by the subaerial oxidation of sulfides exposed on several waste piles. To support remediation efforts, a mineralogical study of the waste piles was undertaken by acquiring reflectance spectra (measured in the visible to short-wave infrared range of light (0.35–2.5 Am) using a portable, digitally integrated pen tablet PC mapping system with differential global positioning system and laser rangefinder support. Analysis of the spectral data made use of a continuum removal and band-shape …
The Conservation Reserve Enhancement Program, Arthur W. Allen
The Conservation Reserve Enhancement Program, Arthur W. Allen
United States Geological Survey: Staff Publications
The Conservation Reserve Enhancement Program (CREP) reflects advancement in U.S. Department of Agriculture agricultural policy by addressing agriculturally related conservation on a multi-farm, landscape scale and establishing funding support and partnerships with state and non-governmental organizations. Underway in 25 states, with more being planned, the CREP addresses environmental issues on the farmed landscape with implications for environmental quality potentially reaching thousands of miles away from where program conservation practices are established. Most CREPs have been initiated only within the last 4 years. Monitoring programs to evaluate CREP performance have been established, but because of time needed to establish vegetative covers, …
Basal Tissue Structure In The Earliest Euconodonts: Testing Hypotheses Of Developmental Plasticity In Euconodont Phylogeny, Xi-Ping Dong, Philip C. J. Donoghue, John E. Repetski
Basal Tissue Structure In The Earliest Euconodonts: Testing Hypotheses Of Developmental Plasticity In Euconodont Phylogeny, Xi-Ping Dong, Philip C. J. Donoghue, John E. Repetski
United States Geological Survey: Staff Publications
The hypothesis that conodonts are vertebrates rests solely on evidence of soft tissue anatomy. This has been corroborated by microstructural, topological and developmental evidence of homology between conodont and vertebrate hard tissues. However, these conclusions have been reached on the basis of evidence from highly derived euconodont taxa and the degree to which they are representative of plesiomorphic euconodonts remains an open question. Furthermore, the range of variation in tissue types comprising the euconodont basal body has been used to establish a hypothesis of developmental plasticity early in the phylogeny of the clade, and a model of diminishing potentiality in …