Differences in Ichthyophonus prevalence and infection severity between upper Yukon River and Tanana River chinook salmon, Oncorhynchus tshawytscha (Walbaum), stocks
R. Kocan, P. Hershberger
2006, Journal of Fish Diseases (29) 497-503
Two genetically distinct populations of chinook salmon, Oncorhynchus tshawytscha (Walbaum), were simultaneously sampled at the confluence of the Yukon and Tanana rivers in 2003. Upper Yukon-Canadian fish had significantly higher infection prevalence as well as more severe infections (higher parasite density in heart tissue) than the lower Yukon-Tanana River fish....
Adequacy of selected evapotranspiration approximations for hydrologic simulation
D. M. Sumner
2006, Journal of the American Water Resources Association (42) 699-711
Evapotranspiration (ET) approximations, usually based on computed potential ET (PET) and diverse PET-to-ET conceptualizations, are routinely used in hydrologic analyses. This study presents an approach to incorporate measured (actual) ET data, increasingly available using micrometeorological methods, to define the adequacy of ET approximations for hydrologic simulation. The approach is demonstrated...
Geophysical setting of the 2000 ML 5.2 Yountville, California, earthquake: Implications for seismic Hazard in Napa Valley, California
V.E. Langenheim, R. W. Graymer, R.C. Jachens
2006, Bulletin of the Seismological Society of America (96) 1192-1198
The epicenter of the 2000 ML 5.2 Yountville earthquake was located 5 km west of the surface trace of the West Napa fault, as defined by Helley and Herd (1977). On the basis of the re-examination of geologic data and the analysis of potential field data, the earthquake occurred on...
Foraging behavior of redheads (Aythya americana) wintering in Texas and Louisiana
M.C. Woodin, T.C. Michot
2006, Conference Paper, Hydrobiologia
Redheads, Aythya americana, concentrate in large numbers annually in traditional wintering areas along the western and northern rim of the Gulf of Mexico. Two of these areas are the Laguna Madre of Texas and Chandeleur Sound of Louisiana. We collected data on 54,340 activities from 103 redhead flocks in Texas...
Earthquakes triggered by silent slip events on Kīlauea volcano, Hawaii
Paul Segall, Emily K. Desmarais, David Shelly, Asta Mikijus, Peter F. Cervelli
2006, Nature (442) 71-74
Slow-slip events, or ‘silent earthquakes’, have recently been discovered in a number of subduction zones including the Nankai trough1, 2, 3 in Japan, Cascadia4, 5, and Guerrero6 in Mexico, but the depths of these events have been difficult to determine from surface deformation measurements. Although it is assumed that...
Blood lead levels of wild Steller's eiders (Polysticta stelleri) and black scoters (Melanitta nigra) in Alaska using a portable blood lead analyzer
Corrine S. Brown, Joanne Luebbert, Daniel M. Mulcahy, Jason L. Schamber, Daniel H. Rosenberg
2006, Journal of Zoo and Wildlife Medicine (37) 361-365
Sea duck populations are declining in Alaska. The reasons for the decline are not known; environmental lead exposure is one suspected cause. Thirty wild Steller's eider ducks (Polysticta stelleri) and 40 wild black scoter ducks (Melanitta nigra) were tested for blood lead levels using a portable blood lead analyzer (LeadCare;...
Preferential flow estimates to an agricultural tile drain with implications for glyphosate transport
W.W. Stone, J.T. Wilson
2006, Journal of Environmental Quality (35) 1825-1835
Agricultural subsurface drains, commonly referred to as tile drains, are potentially significant pathways for the movement of fertilizers and pesticides to streams and ditches in much of the Midwest. Preferential flow in the unsaturated zone provides a route for water and solutes to bypass the soil matrix and reach tile...
Advanced National Siesmic System delivers improved information
S.A. Sipkin, J.R. Filson, H.M. Benz, D.J. Wald, P.S. Earle
2006, Eos, Transactions, American Geophysical Union (87) 365-366
[No abstract available]...
Evidence for wing molt and breeding site fidelity in King Eiders
Laura M. Phillips, A.N. Powell
2006, Waterbirds (29) 148-153
Fidelity of King Eiders (Somateria spectabilis) to breeding and wing molt sites was examined using satellite telemetry data obtained opportunistically when battery life of transmitters provided locations in a second year. Consecutive breeding locations were obtained for eleven female and 23 male King Eiders. All females exhibited breeding site fidelity...
Monitoring planktivorous seabird populations: Validating surface counts of crevice-nesting auklets using mark-resight techniques
L.M. Sheffield, Adrian E. Gall, D.D. Roby, D.B. Irons, K.M. Dugger
2006, Canadian Journal of Zoology (84) 846-854
Least Auklets (Aethia pusilla (Pallas, 1811)) are the most abundant species of seabird in the Bering Sea and offer a relatively efficient means of monitoring secondary productivity in the marine environment. Counting auklets on surface plots is the primary method used to track changes in numbers of these crevice-nesters, but...
Carbon and nitrogen fixation differ between successional stages of biological soil crusts in the Colorado Plateau and Chihuahuan Desert
D.C. Housman, H.H. Powers, A.D. Collins, J. Belnap
2006, Journal of Arid Environments (66) 620-634
Biological soil crusts (cyanobacteria, mosses and lichens collectively) perform essential ecosystem services, including carbon (C) and nitrogen (N) fixation. Climate and land-use change are converting later successional soil crusts to early successional soil crusts with lower C and N fixation rates. To quantify the effect of such conversions on C...
Influence of riffle and snag habitat specific sampling on stream macroinvertebrate assemblage measures in bioassessment
L. Wang, B.W. Weigel, P. Kanehl, K. Lohman
2006, Environmental Monitoring and Assessment (119) 245-273
Stream macroinvertebrate communities vary naturally among types of habitats where they are sampled, which affects the results of environmental assessment. We analyzed macroinvertebrates collected from riffle and snag habitats to evaluate influences of habitat-specific sampling on taxon occurrence, assemblage measures, and biotic indices. We found considerably more macroinvertebrate taxa unique...
Modeling the transport and inactivation of E. coli and enterococci in the near-shore region of Lake Michigan
L. Liu, M.S. Phanikumar, S.L. Molloy, R.L. Whitman, D.A. Shively, M.B. Nevers, D.J. Schwab, J.B. Rose
2006, Environmental Science & Technology (40) 5022-5028
To investigate the transport and fate of fecal pollution at Great Lakes beaches and the health risks associated with swimming, the near-shore waters of Lake Michigan and two tributaries discharging into it were examined for bacterial indicators of human fecal pollution. The enterococcus human fecal pollution marker, which targets a...
Afghan resource assessment fed positive outlook for exploration
T. R. Klett, C. J. Wandrey, G. F. Ulmishek, A. Amirzada
2006, Oil & Gas Journal (104)
Crude oil, natural gas and natural gas liquids/condensate resources are important for the redevelopment of Afghanistan's infrastructure. Improved living and economic conditions in Afghanistan require increasing the availability of energy particularly by exploitation of Afghanistan's petroleum resources. The four total petroleum systems are subdivided into units with homogeneous geologic traits...
The relative roles of environment, history and local dispersal in controlling the distributions of common tree and shrub species in a tropical forest landscape, Panama
J.-C. Svenning, B.M.J. Engelbrecht, D.A. Kinner, T.A. Kursar, R.F. Stallard, S.J. Wright
2006, Journal of Tropical Ecology (22) 575-586
We used regression models and information-theoretic model selection to assess the relative importance of environment, local dispersal and historical contingency as controls of the distributions of 26 common plant species in tropical forest on Barro Colorado Island (BCI), Panama. We censused eighty-eight 0.09-ha plots scattered across the landscape. Environmental control,...
Use of plume mapping data to estimate chlorinated solvent mass loss
J.R. Barbaro, P.P. Neupane
2006, Ground Water Monitoring and Remediation (26) 115-127
Results from a plume mapping study from November 2000 through February 2001 in the sand-and-gravel surficial aquifer at Dover Air Force Base, Delaware, were used to assess the occurrence and extent of chlorinated solvent mass loss by calculating mass fluxes across two transverse cross sections and by observing changes in...
Relationship between shrubs and foods in mountain plover habitat in Park County, Colorado
S.C. Schneider, Michael B. Wunder, F.L. Knopf
2006, Southwestern Naturalist (51) 197-202
We explored habitat use in terms of vegetation structure and potential forage availability for mountain plovers (Charadrius montanus) in Park County, Colorado. We quantified the percentage cover of bare ground, percentage cover of shrubs (Chrysothamnus visadiflorus), linear distance to nearest shrub, arthropod biomass, and grasshopper density for 102 plots of...
One-way coupling of an atmospheric and a hydrologic model in Colorado
L.E. Hay, M.P. Clark, M. Pagowski, G.H. Leavesley, W.J. Gutowski
2006, Journal of Hydrometeorology (7) 569-589
This paper examines the accuracy of high-resolution nested mesoscale model simulations of surface climate. The nesting capabilities of the atmospheric fifth-generation Pennsylvania State University (PSU)-National Center for Atmospheric Research (NCAR) Mesoscale Model (MM5) were used to create high-resolution, 5-yr climate simulations (from 1 October 1994 through 30 September 1999), starting...
Coral bleaching and disease combine to cause extensive mortality on reefs in US Virgin Islands
J. Miller, R. Waara, E. Muller, C. Rogers
2006, Coral Reefs (25) 418
[No abstract available]...
A robust design mark-resight abundance estimator allowing heterogeneity in resighting probabilities
B.T. McClintock, Gary C. White, K.P. Burnham
2006, Journal of Agricultural, Biological, and Environmental Statistics (11) 231-248
This article introduces the beta-binomial estimator (BBE), a closed-population abundance mark-resight model combining the favorable qualities of maximum likelihood theory and the allowance of individual heterogeneity in sighting probability (p). The model may be parameterized for a robust sampling design consisting of multiple primary sampling occasions where closure need not...
Effects of chronic avian malaria (Plasmodium relictum) infection on reproductive success of Hawaii Amakihi (Hemignathus virens)
A.M. Kilpatrick, D.A. Lapointe, C. T. Atkinson, B.L. Woodworth, J.K. Lease, M.E. Reiter, K. Gross
2006, The Auk (123) 764-774
We studied the effects of chronic avian malaria (Plasmodium relictum) infections on the reproductive success of a native Hawaiian honeycreeper, Hawaii Amakihi (Hemignathus virens). Chronic malaria infections in male and female parents did not significantly reduce reproductive success as measured by clutch size, hatching success, fledging mass, number of nestlings...
Electrical resistance sensors record spring flow timing, Grand Canyon, Arizona
E.A. Adams, S. A. Monroe, Abraham E. Springer, K.W. Blasch, D. J. Bills
2006, Ground Water (44) 630-641
Springs along the south rim of the Grand Canyon, Arizona, are important ecological and cultural resources in Grand Canyon National Park and are discharge points for regional and local aquifers of the Coconino Plateau. This study evaluated the applicability of electrical resistance (ER) sensors for measuring diffuse, low-stage (<1.0 cm)...
Trends in snowfall versus rainfall in the western United States
N. Knowles, M. D. Dettinger, D.R. Cayan
2006, Journal of Climate (19) 4545-4559
The water resources of the western United States depend heavily on snowpack to store part of the wintertime precipitation into the drier summer months. A well-documented shift toward earlier runoff in recent decades has been attributed to 1) more precipitation falling as rain instead of snow and 2) earlier snowmelt....
Specific storage volumes: A useful tool for CO2 storage capacity assessment
S.T. Brennan, R.C. Burruss
2006, Natural Resources Research (15) 165-182
Subsurface geologic strata have the potential to store billions of tons of anthropogenic CO2; therefore, geologic carbon sequestration can be an effective mitigation tool used to slow the rate at which levels of atmospheric CO2 are increasing. Oil and gas reservoirs, coal beds, and saline reservoirs can be used for...
Fasting augments PCB impact on liver metabolism in anadromous Arctic Char
M.M. Vijayan, N. Aluru, A.G. Maule, E.H. Jorgensen
2006, Toxicological Sciences (91) 431-439
Anadromous arctic char (Salvelinus alpinus) undertake short feeding migrations to seawater every summer and accumulate lipids, while the rest of the year is spent in fresh water where the accumulated lipid reserves are mobilized. We tested the hypothesis that winter fasting and the associated polychlorinated biphenyls' (PCBs) redistribution from lipid...
