Landbird migration in the American West: Recent progress and future research directions
J.D. Carlisle, S. K. Skagen, B.E. Kus, Charles van Riper III, K.L. Paxton, J.F. Kelly
2009, The Condor (111) 211-225
Our knowledge of avian behaviors during the nonbreeding period still lags behind that of the breeding season, but the last decade has witnessed a proliferation in research that has yielded significant progress in understanding migration patterns of North American birds. And, although historically the great majority of migration research has...
Application of iron and zinc isotopes to track the sources and mechanisms of metal loading in a mountain watershed
D.M. Borrok, R. B. Wanty, Ridley W. Ian, P. J. Lamothe, B. A. Kimball, P. L. Verplanck, R.L. Runkel
2009, Applied Geochemistry (24) 1270-1277
Here the hydrogeochemical constraints of a tracer dilution study are combined with Fe and Zn isotopic measurements to pinpoint metal loading sources and attenuation mechanisms in an alpine watershed impacted by acid mine drainage. In the tested mountain catchment, δ56Fe and δ66Zn isotopic signatures of filtered stream water samples varied by ∼3.5‰ and...
Methods for assessing movement path recursion with application to African buffalo in South Africa
S. Bar-David, I. Bar-David, P.C. Cross, S.J. Ryan, C.U. Knechtel, W.M. Getz
2009, Ecology (90) 2467-2479
Recent developments of automated methods for monitoring animal movement, e.g., global positioning systems (GPS) technology, yield high-resolution spatiotemporal data. To gain insights into the processes creating movement patterns, we present two new techniques for extracting information from these data on repeated visits to a particular site or patch ("recursions"). Identification...
Plants and ventifacts delineate late Holocene wind vectors in the Coachella Valley, USA
Peter G. Griffiths, R. H. Webb, M. Fisher, Allan Muth
2009, Aeolian Research (1) 63-73
Strong westerly winds that emanate from San Gorgonio Pass, the lowest point between Palm Springs and Los Angeles, California, dominate aeolian transport in the Coachella Valley of the western Sonoran Desert. These winds deposit sand in coppice dunes that are critical habitat for several species,...
Environmental and human influences on trumpeter swan habitat occupancy in Alaska
J.H. Schmidt, M. S. Lindberg, D.S. Johnson, J.A. Schmultz
2009, Condor (111) 266-275
Approximately 70-80% of the entire population of the Trumpeter Swan (Cygnus huccinator) depends for reproduction on wetlands in Alaska. This makes the identification of important habitat features and the effects of human interactions important for the species' long-term management. We analyzed the swan's habitat preferences in five areas throughout the...
Longitudinal patterns in flathead catfish relative abundance and length at age within a large river: Effects of an urban gradient
C.P. Paukert, A.S. Makinster
2009, River Research and Applications (25) 861-873
We investigated the spatial variation of flathead catfish (Pylodictis olivaris) relative abundance and growth in the 274 km long Kansas River to determine if population dynamics of catfish are related to urbanization. Electrofishing was conducted at 462 random sites throughout the river in summer, 2005-2006 to collect fish. Relative abundance...
Hydrologic and biogeochemical controls of river subsurface solutes under agriculturally enhanced ground water flow
R.A. Wildman Jr., Joseph L. Domagalski, J. G. Hering
2009, Journal of Environmental Quality (38) 1830-1840
The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural...
Change in abundance of Pacific brant wintering in Alaska: Evidence of a climate warming effect?
David H. Ward, Christian P. Dau, T. Lee Tibbitts, James S. Sedinger, Betty A. Anderson, James E. Hines
2009, Arctic (62) 301-311
Winter distribution of Pacific Flyway brant (Branta bernicla nigricans) has shifted northward from low-temperate areas to sub-Arctic areas over the last 42 years. We assessed the winter abundance and distribution of brant in Alaska to evaluate whether climate warming may be contributing to positive trends in the most northern of...
Response of Sandhill Crane (Grus canadensis) riverine roosting habitat to changes in stage and sandbar morphology
P.J. Kinzel, J. M. Nelson, A.K. Heckman
2009, River Research and Applications (25) 135-152
Over the past century, flow regulation and vegetation encroachment have reduced active channel widths along the central Platte River, Nebraska. During the last two decades, an annual program of in-channel vegetation management has been implemented to stabilize or expand active channel widths. Vegetation management practices are intended to enhance riverine...
The influence of microtopography on soil nutrients in created mitigation wetlands
K.F. Moser, C. Ahn, G.B. Noe
2009, Restoration Ecology (17) 641-651
This study explores the relationship between microtopography and soil nutrients (and trace elements), comparing results for created and reference wetlands in Virginia, and examining the effects of disking during wetland creation. Replicate multiscale tangentially conjoined circular transects were used to quantify microtopography both in terms of elevation and by two...
Spatial and seasonal variations in mercury methylation and microbial community structure in a historic mercury mining area, Yolo County, California
J.M. Holloway, M. B. Goldhaber, K.M. Scow, R.E. Drenovsky
2009, Chemical Geology (267) 85-95
The relationships between soil parent lithology, nutrient concentrations, microbial biomass and community structure were evaluated in soils from a small watershed impacted by historic Hg mining. Upland and wetland soils, stream sediments and tailings were collected and analyzed for nutrients (DOC, SO4=, NO3-), Hg, MeHg, and phospholipid fatty acids (PLFA)....
Do summer temperatures trigger spring maturation in pacific lamprey, Entosphenus tridentatus?
B.J. Clemens, S. Van De Wetering, J. Kaufman, R.A. Holt, C.B. Schreck
2009, Ecology of Freshwater Fish (18) 418-426
Pacific lamprey, Entosphenus tridentatus, return to streams and use somatic energy to fuel maturation. Body size decreases, the lamprey mature, spawn, and then die. We predicted that warm, summer temperatures (>20 ??C) would accentuate shrinkage in body size, and expedite sexual maturation and subsequent death. We compared fish reared in...
Effects of sampling interval on spatial patterns and statistics of watershed nitrogen concentration
S.-S.D. Wu, E.L. Usery, M.P. Finn, D.D. Bosch
2009, GIScience and Remote Sensing (46) 172-186
This study investigates how spatial patterns and statistics of a 30 m resolution, model-simulated, watershed nitrogen concentration surface change with sampling intervals from 30 m to 600 m for every 30 m increase for the Little River Watershed (Georgia, USA). The results indicate that the mean, standard deviation, and variogram...
Environmental contaminants in freshwater fish and their risk to piscivorous wildlife based on a national monitoring program
J.E. Hinck, C. J. Schmitt, K.A. Chojnacki, D. E. Tillitt
2009, Environmental Monitoring and Assessment (152) 469-494
Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites from large U.S. river basins. Potential contaminant sources such as urban and agricultural runoff, industrial discharges, mine drainage, and irrigation varied among the sampling sites. Our objectives were to provide summary statistics for chemical...
Habitat selection for parasite-free space by hosts of parasitic cowbirds
J.T. Forsman, T. E. Martin
2009, Oikos (118) 464-470
Choice of breeding habitat can have a major impact on fitness. Sensitivity of habitat choice to environmental cues predicting reproductive success, such as density of harmful enemy species, should be favored by natural selection. Yet, experimental tests of this idea are in short supply. Brown-headed cowbirds Molothrus ater commonly reduce...
Dramatic declines of DDE and other organochlorines in spring migrant Peregrine Falcons from Padre Island, Texas, 1978-2004
Charles J. Henny, M.A. Yates, W.S. Seegar
2009, Journal of Raptor Research (43) 37-42
Peregrine Falcons (Falco peregrinus) captured in the spring at Padre Island, Texas, nest across the arctic and subarctic from Alaska to Greenland and winter throughout Latin America. Padre Island, located immediately north of the Mexican border, is the peregrines' first landfall in the U.S.A. after spending about 6 mo in...
Timing of occurrence of large submarine landslides on the Atlantic Ocean margin
H.J. Lee
2009, Marine Geology (264) 53-64
Submarine landslides are distributed unevenly both in space and time. Spatially, they occur most commonly in fjords, active river deltas, submarine canyon-fan systems, the open continental slope and on the flanks of oceanic volcanic islands. Temporally, they are influenced by the size, location, and sedimentology of migrating depocenters, changes in...
On the reported magnetic precursor of the 1993 guam earthquake
J.N. Thomas, J.J. Love, M.J.S. Johnston, K. Yumoto
2009, Geophysical Research Letters (36)
Using 1-second magnetometer data recorded 67 km from the epicenter of the 1993 Mw 7.7 Guam earthquake, Hayakawa et al. (1996) and Miyahara et al. (1999) identify anomalous precursory changes in ultra-low frequency magnetic polarization (the ratio of vertical to horizontal field components). In a check of their results, we...
Seabird nest counts: A test of monitoring metrics using Red-tailed Tropicbirds
N.E. Seavy, M.H. Reynolds
2009, Journal of Field Ornithology (80) 297-302
Counts of nesting birds are often used to monitor the abundance of breeding pairs at colonies. Mean incubation counts (MICs) are counts of nests with eggs at intervals that correspond to the mean incubation period of a species. The sum of all counts during the nesting season (MICtotal) and the...
Hydrolysis of polycarbonate in sub-critical water in fused silica capillary reactor with in situ Raman spectroscopy
Z. Pan, I-Ming Chou, R.C. Burruss
2009, Green Chemistry (11) 1105-1107
The advantages of using fused silica capillary reactor (FSCR) instead of conventional autoclave for studying chemical reactions at elevated pressure and temperature conditions were demonstrated in this study, including the allowance for visual observation under a microscope and in situ Raman spectroscopic characterization of polycarbonate and coexisting phases during hydrolysis in subcritical water....
Investigation of uptake and retention of atmospheric Hg(II) by boreal forest plants using stable Hg isotopes
J.A. Graydon, Louis, H. Hintelmann, S.E. Lindberg, K.A. Sandilands, J.W.M. Rudd, C.A. Kelly, M.T. Tate, D. P. Krabbenhoft, I. Lehnherr
2009, Environmental Science & Technology (43) 4960-4966
Although there is now a general consensus among mercury (Hg) biogeochemists that increased atmospheric inputs of inorganic Hg(II) to lakes and watersheds can result in increased methylmercury (MeHg) concentrations in fish, researchers still lack kinetic data describing the movement of Hg from the atmosphere, through watershed and lake ecosystems, and...
Genetic diversity among brazilian isolates of beauveria bassiana: comparisons with non-brazilian isolates and other beauveria species
E.K.K. Fernandes, A.M.L. Moraes, R.S. Pacheco, D.E.N. Rangel, M.P. Miller, V.R.E.P. Bittencourt, D.W. Roberts
2009, Journal of Applied Microbiology (107) 760-774
Aims: The genetic diversity of Beauveria bassiana was investigated by comparing isolates of this species to each other (49 from different geographical regions of Brazil and 4 from USA) and to other Beauveria spp. Methods and Results: The isolates were examined by multilocus enzyme electrophoresis (MLEE), amplified fragment length polymorphism...
Probability of detection of nests and implications for survey design
P.A. Smith, J. Bart, Richard B. Lanctot, B. J. McCaffery, S. Brown
2009, Condor (111) 414-423
Surveys based on double sampling include a correction for the probability of detection by assuming complete enumeration of birds in an intensively surveyed subsample of plots. To evaluate this assumption, we calculated the probability of detecting active shorebird nests by using information from observers who searched the same plots independently....
Selenium and trace element mobility affected by periodic displacement of stratification in the Great Salt Lake, Utah
K. Beisner, D. L. Naftz, W.P. Johnson, X. Diaz
2009, Science of the Total Environment (407) 5263-5273
The Great Salt Lake (GSL) is a unique ecosystem in which trace element activity cannot be characterized by standard geochemical parameters due to the high salinity. Movement of selenium and other trace elements present in the lake bed sediments of GSL may occur due to periodic stratification displacement events or...
Assessment of source probabilities for potential tsunamis affecting the U.S. Atlantic coast
E.L. Geist, T. Parsons
2009, Marine Geology (264) 98-108
Estimating the likelihood of tsunamis occurring along the U.S. Atlantic coast critically depends on knowledge of tsunami source probability. We review available information on both earthquake and landslide probabilities from potential sources that could generate local and transoceanic tsunamis. Estimating source probability includes defining both size and recurrence distributions for...
