Response of mountain meadows to grazing by recreational pack stock
David N. Cole, Jan W. Van Wagtendonk, Mitchel P. McClaran, Peggy E. Moore, Neil K. McDougald
2004, Journal of Range Management (57) 153-160
Effects of recreational pack stock grazing on mountain meadows in Yosemite National Park were assessed in a 5-year study. Yosemite is a designated wilderness, to be managed such that its natural conditions are preserved. Studies were conducted in 3 characteristic meadow types: shorthair sedge (Carex filifolia Nutt.), Brewer's reed grass...
The Late Cambrian SPICE (δ13C) event and the Sauk II-Sauk III regression: new evidence from Laurentian basins in Utah, Iowa, and Newfoundland
Matthew R. Saltzman, Clinton A. Cowan, Anthony C. Runkel, Bruce Runnegar, Michael C. Stewart, Allison R. Palmer
2004, Journal of Sedimentary Research (74) 366-377
Carbon isotope data from Upper Cambrian sections in three Laurentian basins in northern Utah, central Iowa, and western Newfoundland record a large positive ??13C excursion (SPICE event) of up to + 5???. Peak ??13C ratios are well dated by trilobite collections to the middle of the Steptoean Stage (Dunderbergia Zone)...
Population dynamics of bloaters Coregonus hoyi in Lake Huron, 1980-1998
Jeffrey S. Schaeffer
2004, Annales Zoologici Fennici (41) 271-279
I investigated population dynamics of bloaters Coregonus hoyi in Lake Huron using data collected during 1980-1998 from fixed-site trawl surveys. Bloaters were uncommon in 1980, but abundance increased during 1980-1992 through a series of strong year classes. High adult abundance appeared to suppress recruitment after 1992, and the population subsequently...
Rapid assessment indicator of wetland integrity as an unintended predictor of avian diversity
Martin A. Stapanian, Thomas A. Waite, Gregory Krzys, John J. Mack, Mick Micacchion
2004, Hydrobiologia (520) 119-126
Rapid assessment of aquatic ecosystems has been widely implemented, sometimes without thorough evaluation of the robustness of rapid assessment metrics as indicators of ecological integrity. Here, we evaluate whether the Ohio Rapid Assessment Method (ORAM) for Wetlands Version 5.0 is a useful indicator of ecological integrity beyond its intended purpose....
Evaluation of a chinook salmon (Oncorhynchus tshawytscha) bioenergetics model
Charles P. Madenjian, Daniel V. O’Connor, Sergei M. Chernyak, Richard R. Rediske, James P. O'Keefe
2004, Canadian Journal of Fisheries and Aquatic Sciences (61) 627-635
We evaluated the Wisconsin bioenergetics model for chinook salmon (Oncorhynchus tshawytscha) in both the laboratory and the field. Chinook salmon in laboratory tanks were fed alewife (Alosa pseudoharengus), the predominant food of chinook salmon in Lake Michigan. Food consumption and growth by chinook salmon during the experiment were measured. To...
Evaluation of multidimensional transport through a field-scale compacted soil liner
T.W. Willingham, C.J. Werth, A.J. Valocchi, I.G. Krapac, C. Toupiol, T.D. Stark, D.E. Daniel
2004, Journal of Geotechnical and Geoenvironmental Engineering (130) 887-895
A field-scale compacted soil liner was constructed at the University of Illinois at Urbana-Champaign by the U.S. Environmental Protection Agency (USEPA) and Illinois State Geological Survey in 1988 to investigate chemical transport rates through low permeability compacted clay liners (CCLs). Four tracers (bromide and three benzoic acid tracers) were each...
Microbial precipitation of dolomite in methanogenic groundwater
Jennifer A. Roberts, Philip C. Bennett, Luis A. Gonzalez, G.L. Macpherson, Kitty L. Milliken
2004, Geology (32) 277-280
We report low-temperature microbial precipitation of dolomite in dilute natural waters from both field and laboratory experiments. In a freshwater aquifer, microorganisms colonize basalt and nucleate nonstoichiometric dolomite on cell walls. In the laboratory, ordered dolomite formed at near-equilibrium conditions from groundwater with molar Mg:Ca ratios of <1; dolomite was...
Transport and time lag of chlorofluorocarbon gases in the unsaturated zone, Rabis Creek, Denmark
Peter Engesgaard, Anker L. Højberg, Klaus Hinsby, Karsten H. Jensen, Troels Laier, Flemming Larsen, Eurybiades Busenberg, Niel Plummer
2004, Vadose Zone Journal (3) 1249-1261
Transport of chlorofluorocarbon (CFC) gases through the unsaturated zone to the water table is affected by gas diffusion, air–water exchange (solubility), sorption to the soil matrix, advective–dispersive transport in the water phase, and, in some cases, anaerobic degradation. In deep unsaturated zones, this may lead to a time lag between...
Implications of hydrologic variability on the succession of plants in Great Lakes wetlands
Douglas A. Wilcox
2004, Aquatic Ecosystem Health & Management (7) 223-231
Primary succession of plant communities directed toward a climax is not a typical occurrence in wetlands because these ecological systems are inherently dependent on hydrology, and temporal hydrologic variability often causes reversals or setbacks in succession. Wetlands of the Great Lakes provide good examples for demonstrating the implications of hydrology...
The status of Limnocalanus macrurus (Copepoda: Calanoida: Centropagidae) in Lake Erie
Douglas D. Kane, John E. Gannon, David A. Culver
2004, Journal of Great Lakes Research (30) 22-30
The calanoid copepod Limnocalanus macrurus showed large declines in abundance and a narrowing of spatial distribution with the onset of cultural eutrophication and increases in rainbow smelt (Osmerus mordax) abundances in Lake Erie in the mid 20th century. Since 1995, however, Limnocalanus macrurus appears to have repopulated in western Lake Erie to levels of...
Trophic transfer efficiency of DDT to lake trout (Salvelinus namaycush) from their prey
C.P. Madenjian, D.V. O’Connor
2004, Bulletin of Environmental Contamination and Toxicology (72) 1219-1225
The objective of our study was to determine the efficiency with which lake trout retain DDT from their natural food. Our estimate of DDT assimilation efficiency would represent the most realistic estimate, to date, for use in risk assessment models....
Dietary uptake of polychlorinated biphenyls (PCBs) by rainbow trout
Robert F. Carline, Patrick M. Barry, H. George Ketola
2004, North American Journal of Aquaculture (66) 91-99
The presence of detectable levels of polychlorinated biphenyls (PCBs) in commercially produced fish feed has raised a concern about the degree of biomagnification of these contaminants in hatchery-reared trout. Our objectives were to (1) define the relationship between concentrations of PCBs in fish feed and in fish tissue and (2)...
Time-dependent lethal body residues for the toxicity of pentachlorobenzene to Hyalella azteca
Peter F. Landrum, Jeffery A. Steevens, Duane C. Gossiaux, Michael McElroy, Sander Robinson, Linda Begnoche, Sergei Chernyak, James Hickey
2004, Environmental Toxicology and Chemistry (23) 1335-1343
The study examined the temporal response of Hyalella azteca to pentachlorobenzene (PCBZ) in water-only exposures. Toxicity was evaluated by calculating the body residue of PCBZ associated with survival. The concentration of PCBZ in the tissues of H. azteca associated with 50% mortality decreased from 3 to 0.5 μmol/g over the temporal range of 1...
Status of lake trout rehabilitation on Six Fathom Bank and Yankee Reef in Lake Huron
Charles P. Madenjian, Timothy J. Desorcie, Jerry R. McClain, Aaron P. Woldt, Jeffrey D. Holuszko, Charles A. Bowen II
2004, North American Journal of Fisheries Management (24) 1003-1016
Six Fathom Bank, an offshore reef in the central region of Lake Huron's main basin, was stocked annually with hatchery-reared lake trout Salvelinus namaycush during 1985–1998, and nearby Yankee Reef was stocked with hatchery-reared lake trout in 1992, 1997, and annually during 1999–2001. We conducted gill-net surveys during spring and fall to...
Great Lakes clams find refuge from zebra mussels in restored, lake-connected marsh (Ohio)
S. Jerrine Nichols, Douglas A. Wilcox
2004, Ecological Restoration (22) 51-52
Since the early 1990s, more than 95 percent of the freshwater clams once found in Lake Erie have died due to the exotic zebara mussel (Dreissena polymorpha). Zebra mussels attach themselves to native clams in large numbers, impeding the ability of the clams to eat and burrow. However, in...
Escherichia coli sampling reliability at a frequently closed Chicago beach: monitoring and management implications
Richard L. Whitman, Meredith B. Nevers
2004, Environmental Science & Technology (38) 4241-4246
Monitoring beaches for recreational water quality is becoming more common, but few sampling designs or policy approaches have evaluated the efficacy of monitoring programs. The authors intensively sampled water for E. coli (N=1770) at 63rd Street Beach, Chicago for 6 months in 2000 in order to (1) characterize spatial-temporal trends, (2) determine...
Spawning by lake sturgeon (Acipenser fulvescens) in the Detroit River
N.M. Caswell, D. L. Peterson, B.A. Manny, G.W. Kennedy
2004, Journal of Applied Ichthyology (20) 1-6
Overfishing and habitat destruction in the early 1900s devastated lake sturgeon (Acipenser fulvescens) populations in the Great Lakes. Although a comprehensive restoration strategy for this species was recently drafted by the Michigan Department of Natural Resources, a lack of current data on Great Lakes sturgeon stocks has hindered rehabilitation efforts....
Overwinter survival of juvenile lake herring in relation to body size, physiological condition, energy stores, and food ration
Kevin L. Pangle, Trent M. Sutton, Ronald E. Kinnunen, Michael H. Hoff
2004, Transactions of the American Fisheries Society (133) 1235-1246
Populations of lake herring Coregonus artedi in Lake Superior have exhibited high recruitment variability over the past three decades. To improve our understanding of the mechanisms which influence year-class strength, we conducted a 225-d laboratory experiment to evaluate the effects of body size, physiological condition, energy stores, and food ration on the...
Status of the shortjaw cisco (Coregonus zenithicus) in Lake Superior
Michael H. Hoff, Thomas N. Todd
2004, Annales Zoologici Fennici (41) 147-154
The shortjaw cisco (Coregonus zenithicus) was historically found in Lakes Huron, Michigan, and Superior, but has been extirpated in Lakes Huron and Michigan apparently as the result of commercial overharvest. During 1999-2001, we conducted an assessment of shortjaw cisco abundance in five areas, spanning the U.S. waters of Lake Superior,...
Genetic variability among lake whitefish from Isle Royale and the Upper Great Lakes
Wendylee Stott, Thomas N. Todd, Larry Kallemeyn
2004, Annales Zoologici Fennici (41) 51-59
The coregonine fishes from Isle Royale National Park represent a unique group that has escaped the successional changes observed elsewhere in North America. Analysis of microsatellite DNA loci revealed significant genetic differences among samples of lake whitefish (Coregonus clupeaformis) from Isle Royale, Lake Superior, and Lake Huron. The amount of...
Occurrence of Ergasilus megaceros Wilson, 1916, in the sea lamprey and other fishes from North America
Patrick M. Muzzall, Patrick L. Hudson
2004, Journal of Parasitology (90) 184-185
Ergasilus megaceros (Copepoda: Ergasilidae) was recovered from the nasal fossae (lamellae) of the olfactory sac in 1 (1.8%) of 56 sea lampreys, Petromyzon marinus Linne, 1758, collected in May 2002 from the Cheboygan River, Michigan. Although the sea lamprey is a new host record for E. megaceros, this fish species may not be a...
Comparative habitat use in a juniper woodland bird community
D.C. Pavlacky Jr., S.H. Anderson
2004, Western North American Naturalist (64) 376-384
We compared vegetation structure used by 14 bird species during the 1998 and 1999 breeding seasons to determine what habitat features best accounted for habitat division and community organization in Utah juniper (Juniperus osteosperma) woodlands of southwestern Wyoming. Habitat use was quantified by measuring 24 habitat variables in 461 bird-centered...
Transient uplift after a 17th-century earthquake along the kuril subduction zone
Y. Sawai, K. Satake, T. Kamataki, H. Nasu, M. Shishikura, B.F. Atwater, B. P. Horton, H.M. Kelsey, T. Nagumo, M. Yamaguchi
2004, Science (306) 1918-1920
In eastern Hokkaido, 60 to 80 kilometers above a subducting oceanic plate, tidal mudflats changed into freshwater forests during the first decades after a 17th-century tsunami. The mudflats gradually rose by a meter, as judged from fossil diatom assemblages. Both the tsunami and the ensuing uplift exceeded any in the...
Soils of eagle crater and Meridiani Planum at the opportunity Rover landing site
Laurence A. Soderblom, R. C. Anderson, R. E. Arvidson, J.F. Bell III, N.A. Cabrol, W. Calvin, P. R. Christensen, B. C. Clark, T. Economou, B.L. Ehlmann, W. H. Farrand, D. Fike, Ralf Gellert, T.D. Glotch, M.P. Golombek, R. Greeley, J.P. Grotzinger, Kenneth E. Herkenhoff, D.J. Jerolmack, J. R. Johnson, B. Jolliff, C. Klingelhofer, A.H. Knoll, Z.A. Learner, R. Li, M. C. Malin, S. M. McLennan, H.Y. McSween, D. W. Ming, R.V. Morris, J. W. Rice Jr., L. Richter, R. Rieder, D. Rodionov, C. Schroder, F.P. Seelos IV, J.M. Soderblom, S. W. Squyres, R. Sullivan, W.A. Watters, C.M. Weitz, M.B. Wyatt, A. Yen, J. Zipfel
2004, Science (306) 1723-1726
The soils at the Opportunity site are fine-grained basaltic sands mixed with dust and sulfate-rich outcrop debris. Hematite is concentrated in spherules eroded from the strata. Ongoing saltation exhumes the spherules and their fragments, concentrating them at the surface. Spherules emerge from soils coated, perhaps from subsurface cementation, by salts....
Distribution and abundance of pelagic fish in Lake Powell, Utah, and Lake Mead, Arizona-Nevada
G.A. Mueller, M.J. Horn
2004, Western North American Naturalist (64) 306-311
Pelagic fish communities (waters with depths >20 m) of Lakes Powell and Mead were examined quarterly from 1995 to 1998 using vertical gill nets and a scientific echosounder. Nets captured a total of 449 fish consisting of striped bass (57%/45% [Lake Powell/Lake Mead]), threadfin shad (24%/50%), common carp (15%/4%), walleye...
